spirv_hlsl.cpp

/*
 * Copyright 2016-2021 Robert Konrad
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

/*
 * At your option, you may choose to accept this material under either:
 *  1. The Apache License, Version 2.0, found at <http://www.apache.org/licenses/LICENSE-2.0>, or
 *  2. The MIT License, found at <http://opensource.org/licenses/MIT>.
 */

#include "spirv_hlsl.hpp"
#include "GLSL.std.450.h"
#include <algorithm>
#include <assert.h>

using namespace spv;
using namespace SPIRV_CROSS_NAMESPACE;
using namespace std;

#define SPIRV_CROSS_INVALID_CALL() assert(false);

enum ExtraSubExpressionType
{
	// Create masks above any legal ID range to allow multiple address spaces into the extra_sub_expressions map.
	EXTRA_SUB_EXPRESSION_TYPE_STREAM_OFFSET = 0x10000000,
	EXTRA_SUB_EXPRESSION_TYPE_AUX = 0x20000000
};


enum class ImageFormatNormalizedState
{
	None = 0,
	Unorm = 1,
	Snorm = 2
};

static bool opcode_is_precision_sensitive_operation(Op op)
{
	switch (op)
	{
	case OpFAdd:
	case OpFSub:
	case OpFMul:
	case OpFNegate:
	case OpIAdd:
	case OpISub:
	case OpIMul:
	case OpSNegate:
	case OpFMod:
	case OpFDiv:
	case OpFRem:
	case OpSMod:
	case OpSDiv:
	case OpSRem:
	case OpUMod:
	case OpUDiv:
	case OpVectorTimesMatrix:
	case OpMatrixTimesVector:
	case OpMatrixTimesMatrix:
	case OpDPdx:
	case OpDPdy:
	case OpDPdxCoarse:
	case OpDPdyCoarse:
	case OpDPdxFine:
	case OpDPdyFine:
	case OpFwidth:
	case OpFwidthCoarse:
	case OpFwidthFine:
	case OpVectorTimesScalar:
	case OpMatrixTimesScalar:
	case OpOuterProduct:
	case OpFConvert:
	case OpSConvert:
	case OpUConvert:
	case OpConvertSToF:
	case OpConvertUToF:
	case OpConvertFToU:
	case OpConvertFToS:
		return true;

	default:
		return false;
	}
}

static ImageFormatNormalizedState image_format_to_normalized_state(ImageFormat fmt)
{
	switch (fmt)
	{
	case ImageFormatR8:
	case ImageFormatR16:
	case ImageFormatRg8:
	case ImageFormatRg16:
	case ImageFormatRgba8:
	case ImageFormatRgba16:
	case ImageFormatRgb10A2:
		return ImageFormatNormalizedState::Unorm;

	case ImageFormatR8Snorm:
	case ImageFormatR16Snorm:
	case ImageFormatRg8Snorm:
	case ImageFormatRg16Snorm:
	case ImageFormatRgba8Snorm:
	case ImageFormatRgba16Snorm:
		return ImageFormatNormalizedState::Snorm;

	default:
		break;
	}

	return ImageFormatNormalizedState::None;
}

static uint32_t pls_format_to_components(PlsFormat format)
{
	switch (format)
	{
	default:
	case PlsR32F:
	case PlsR32UI:
		return 1;

	case PlsRG16F:
	case PlsRG16:
	case PlsRG16UI:
	case PlsRG16I:
		return 2;

	case PlsR11FG11FB10F:
		return 3;

	case PlsRGB10A2:
	case PlsRGBA8:
	case PlsRGBA8I:
	case PlsRGB10A2UI:
	case PlsRGBA8UI:
		return 4;
	}
}

static bool is_unsigned_glsl_opcode(GLSLstd450 op)
{
	// Don't have to be exhaustive, only relevant for legacy target checking ...
	switch (op)
	{
	case GLSLstd450UClamp:
	case GLSLstd450UMin:
	case GLSLstd450UMax:
	case GLSLstd450FindUMsb:
		return true;

	default:
		return false;
	}
}

static bool packing_has_flexible_offset(BufferPackingStandard packing)
{
	switch (packing)
	{
	case BufferPackingStd140:
	case BufferPackingStd430:
	case BufferPackingScalar:
	case BufferPackingHLSLCbuffer:
		return false;

	default:
		return true;
	}
}

static bool packing_is_scalar(BufferPackingStandard packing)
{
	switch (packing)
	{
	case BufferPackingScalar:
	case BufferPackingScalarEnhancedLayout:
		return true;

	default:
		return false;
	}
}

static bool packing_is_vec4_padded(BufferPackingStandard packing)
{
	switch (packing)
	{
	case BufferPackingHLSLCbuffer:
	case BufferPackingHLSLCbufferPackOffset:
	case BufferPackingStd140:
	case BufferPackingStd140EnhancedLayout:
		return true;

	default:
		return false;
	}
}

static BufferPackingStandard packing_to_substruct_packing(BufferPackingStandard packing)
{
	switch (packing)
	{
	case BufferPackingStd140EnhancedLayout:
		return BufferPackingStd140;
	case BufferPackingStd430EnhancedLayout:
		return BufferPackingStd430;
	case BufferPackingHLSLCbufferPackOffset:
		return BufferPackingHLSLCbuffer;
	case BufferPackingScalarEnhancedLayout:
		return BufferPackingScalar;
	default:
		return packing;
	}
}

// Instructions which just load data but don't do any arithmetic operation should just inherit the decoration.
// SPIR-V doesn't require this, but it's somewhat implied it has to work this way, relaxed precision is only
// relevant when operating on the IDs, not when shuffling things around.
static bool opcode_is_precision_forwarding_instruction(Op op, uint32_t &arg_count)
{
	switch (op)
	{
	case OpLoad:
	case OpAccessChain:
	case OpInBoundsAccessChain:
	case OpCompositeExtract:
	case OpVectorExtractDynamic:
	case OpSampledImage:
	case OpImage:
	case OpCopyObject:

	case OpImageRead:
	case OpImageFetch:
	case OpImageSampleImplicitLod:
	case OpImageSampleProjImplicitLod:
	case OpImageSampleDrefImplicitLod:
	case OpImageSampleProjDrefImplicitLod:
	case OpImageSampleExplicitLod:
	case OpImageSampleProjExplicitLod:
	case OpImageSampleDrefExplicitLod:
	case OpImageSampleProjDrefExplicitLod:
	case OpImageGather:
	case OpImageDrefGather:
	case OpImageSparseRead:
	case OpImageSparseFetch:
	case OpImageSparseSampleImplicitLod:
	case OpImageSparseSampleProjImplicitLod:
	case OpImageSparseSampleDrefImplicitLod:
	case OpImageSparseSampleProjDrefImplicitLod:
	case OpImageSparseSampleExplicitLod:
	case OpImageSparseSampleProjExplicitLod:
	case OpImageSparseSampleDrefExplicitLod:
	case OpImageSparseSampleProjDrefExplicitLod:
	case OpImageSparseGather:
	case OpImageSparseDrefGather:
		arg_count = 1;
		return true;

	case OpVectorShuffle:
		arg_count = 2;
		return true;

	case OpCompositeConstruct:
		return true;

	default:
		break;
	}

	return false;
}

static unsigned image_format_to_components(ImageFormat fmt)
{
	switch (fmt)
	{
	case ImageFormatR8:
	case ImageFormatR16:
	case ImageFormatR8Snorm:
	case ImageFormatR16Snorm:
	case ImageFormatR16f:
	case ImageFormatR32f:
	case ImageFormatR8i:
	case ImageFormatR16i:
	case ImageFormatR32i:
	case ImageFormatR8ui:
	case ImageFormatR16ui:
	case ImageFormatR32ui:
		return 1;

	case ImageFormatRg8:
	case ImageFormatRg16:
	case ImageFormatRg8Snorm:
	case ImageFormatRg16Snorm:
	case ImageFormatRg16f:
	case ImageFormatRg32f:
	case ImageFormatRg8i:
	case ImageFormatRg16i:
	case ImageFormatRg32i:
	case ImageFormatRg8ui:
	case ImageFormatRg16ui:
	case ImageFormatRg32ui:
		return 2;

	case ImageFormatR11fG11fB10f:
		return 3;

	case ImageFormatRgba8:
	case ImageFormatRgba16:
	case ImageFormatRgb10A2:
	case ImageFormatRgba8Snorm:
	case ImageFormatRgba16Snorm:
	case ImageFormatRgba16f:
	case ImageFormatRgba32f:
	case ImageFormatRgba8i:
	case ImageFormatRgba16i:
	case ImageFormatRgba32i:
	case ImageFormatRgba8ui:
	case ImageFormatRgba16ui:
	case ImageFormatRgba32ui:
	case ImageFormatRgb10a2ui:
		return 4;

	case ImageFormatUnknown:
		return 4; // Assume 4.

	default:
		SPIRV_CROSS_THROW("Unrecognized typed image format.");
	}
}

static bool packing_is_hlsl(BufferPackingStandard packing)
{
	switch (packing)
	{
	case BufferPackingHLSLCbuffer:
	case BufferPackingHLSLCbufferPackOffset:
		return true;

	default:
		return false;
	}
}

static string image_format_to_type(ImageFormat fmt, SPIRType::BaseType basetype)
{
	switch (fmt)
	{
	case ImageFormatR8:
	case ImageFormatR16:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "unorm float";
	case ImageFormatRg8:
	case ImageFormatRg16:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "unorm float2";
	case ImageFormatRgba8:
	case ImageFormatRgba16:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "unorm float4";
	case ImageFormatRgb10A2:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "unorm float4";

	case ImageFormatR8Snorm:
	case ImageFormatR16Snorm:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "snorm float";
	case ImageFormatRg8Snorm:
	case ImageFormatRg16Snorm:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "snorm float2";
	case ImageFormatRgba8Snorm:
	case ImageFormatRgba16Snorm:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "snorm float4";

	case ImageFormatR16f:
	case ImageFormatR32f:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "float";
	case ImageFormatRg16f:
	case ImageFormatRg32f:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "float2";
	case ImageFormatRgba16f:
	case ImageFormatRgba32f:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "float4";

	case ImageFormatR11fG11fB10f:
		if (basetype != SPIRType::Float)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "float3";

	case ImageFormatR8i:
	case ImageFormatR16i:
	case ImageFormatR32i:
		if (basetype != SPIRType::Int)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "int";
	case ImageFormatRg8i:
	case ImageFormatRg16i:
	case ImageFormatRg32i:
		if (basetype != SPIRType::Int)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "int2";
	case ImageFormatRgba8i:
	case ImageFormatRgba16i:
	case ImageFormatRgba32i:
		if (basetype != SPIRType::Int)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "int4";

	case ImageFormatR8ui:
	case ImageFormatR16ui:
	case ImageFormatR32ui:
		if (basetype != SPIRType::UInt)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "uint";
	case ImageFormatRg8ui:
	case ImageFormatRg16ui:
	case ImageFormatRg32ui:
		if (basetype != SPIRType::UInt)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "uint2";
	case ImageFormatRgba8ui:
	case ImageFormatRgba16ui:
	case ImageFormatRgba32ui:
		if (basetype != SPIRType::UInt)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "uint4";
	case ImageFormatRgb10a2ui:
		if (basetype != SPIRType::UInt)
			SPIRV_CROSS_THROW("Mismatch in image type and base type of image.");
		return "uint4";

	case ImageFormatUnknown:
		switch (basetype)
		{
		case SPIRType::Float:
			return "float4";
		case SPIRType::Int:
			return "int4";
		case SPIRType::UInt:
			return "uint4";
		default:
			SPIRV_CROSS_THROW("Unsupported base type for image.");
		}

	default:
		SPIRV_CROSS_THROW("Unrecognized typed image format.");
	}
}

const char *CompilerHLSL::ShaderSubgroupSupportHelper::get_extension_name(Candidate c)
{
	static const char *const retval[CandidateCount] = { "GL_KHR_shader_subgroup_ballot",
		                                                "GL_KHR_shader_subgroup_basic",
		                                                "GL_KHR_shader_subgroup_vote",
		                                                "GL_KHR_shader_subgroup_arithmetic",
		                                                "GL_NV_gpu_shader_5",
		                                                "GL_NV_shader_thread_group",
		                                                "GL_NV_shader_thread_shuffle",
		                                                "GL_ARB_shader_ballot",
		                                                "GL_ARB_shader_group_vote",
		                                                "GL_AMD_gcn_shader" };
	return retval[c];
}

SmallVector<std::string> CompilerHLSL::ShaderSubgroupSupportHelper::get_extra_required_extension_names(Candidate c)
{
	switch (c)
	{
	case ARB_shader_ballot:
		return { "GL_ARB_shader_int64" };
	case AMD_gcn_shader:
		return { "GL_AMD_gpu_shader_int64", "GL_NV_gpu_shader5" };
	default:
		return {};
	}
}

const char *CompilerHLSL::ShaderSubgroupSupportHelper::get_extra_required_extension_predicate(Candidate c)
{
	switch (c)
	{
	case ARB_shader_ballot:
		return "defined(GL_ARB_shader_int64)";
	case AMD_gcn_shader:
		return "(defined(GL_AMD_gpu_shader_int64) || defined(GL_NV_gpu_shader5))";
	default:
		return "";
	}
}

CompilerHLSL::ShaderSubgroupSupportHelper::FeatureVector CompilerHLSL::ShaderSubgroupSupportHelper::
    get_feature_dependencies(Feature feature)
{
	switch (feature)
	{
	case SubgroupAllEqualT:
		return { SubgroupBroadcast_First, SubgroupAll_Any_AllEqualBool };
	case SubgroupElect:
		return { SubgroupBallotFindLSB_MSB, SubgroupBallot, SubgroupInvocationID };
	case SubgroupInverseBallot_InclBitCount_ExclBitCout:
		return { SubgroupMask };
	case SubgroupBallotBitCount:
		return { SubgroupBallot };
	case SubgroupArithmeticIAddReduce:
	case SubgroupArithmeticIAddInclusiveScan:
	case SubgroupArithmeticFAddReduce:
	case SubgroupArithmeticFAddInclusiveScan:
	case SubgroupArithmeticIMulReduce:
	case SubgroupArithmeticIMulInclusiveScan:
	case SubgroupArithmeticFMulReduce:
	case SubgroupArithmeticFMulInclusiveScan:
		return { SubgroupSize, SubgroupBallot, SubgroupBallotBitCount, SubgroupMask, SubgroupBallotBitExtract };
	case SubgroupArithmeticIAddExclusiveScan:
	case SubgroupArithmeticFAddExclusiveScan:
	case SubgroupArithmeticIMulExclusiveScan:
	case SubgroupArithmeticFMulExclusiveScan:
		return { SubgroupSize, SubgroupBallot, SubgroupBallotBitCount,
			     SubgroupMask, SubgroupElect,  SubgroupBallotBitExtract };
	default:
		return {};
	}
}

CompilerHLSL::ShaderSubgroupSupportHelper::FeatureMask CompilerHLSL::ShaderSubgroupSupportHelper::
    get_feature_dependency_mask(Feature feature)
{
	return build_mask(get_feature_dependencies(feature));
}

bool CompilerHLSL::ShaderSubgroupSupportHelper::can_feature_be_implemented_without_extensions(Feature feature)
{
	static const bool retval[FeatureCount] = {
		false, false, false, false, false, false,
		true, // SubgroupBalloFindLSB_MSB
		false, false, false, false,
		true, // SubgroupMemBarrier - replaced with workgroup memory barriers
		false, false, true, false,
		false, false, false, false, false, false, // iadd, fadd
		false, false, false, false, false, false, // imul , fmul
	};

	return retval[feature];
}

CompilerHLSL::ShaderSubgroupSupportHelper::Candidate CompilerHLSL::ShaderSubgroupSupportHelper::
    get_KHR_extension_for_feature(Feature feature)
{
	static const Candidate extensions[FeatureCount] = {
		KHR_shader_subgroup_ballot, KHR_shader_subgroup_basic,  KHR_shader_subgroup_basic,  KHR_shader_subgroup_basic,
		KHR_shader_subgroup_basic,  KHR_shader_subgroup_ballot, KHR_shader_subgroup_ballot, KHR_shader_subgroup_vote,
		KHR_shader_subgroup_vote,   KHR_shader_subgroup_basic,  KHR_shader_subgroup_basic, KHR_shader_subgroup_basic,
		KHR_shader_subgroup_ballot, KHR_shader_subgroup_ballot, KHR_shader_subgroup_ballot, KHR_shader_subgroup_ballot,
		KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic,
		KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic,
		KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic,
		KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic, KHR_shader_subgroup_arithmetic,
	};

	return extensions[feature];
}

void CompilerHLSL::ShaderSubgroupSupportHelper::request_feature(Feature feature)
{
	feature_mask |= (FeatureMask(1) << feature) | get_feature_dependency_mask(feature);
}

bool CompilerHLSL::ShaderSubgroupSupportHelper::is_feature_requested(Feature feature) const
{
	return (feature_mask & (1u << feature)) != 0;
}

CompilerHLSL::ShaderSubgroupSupportHelper::Result CompilerHLSL::ShaderSubgroupSupportHelper::resolve() const
{
	Result res;

	for (uint32_t i = 0u; i < FeatureCount; ++i)
	{
		if (feature_mask & (1u << i))
		{
			auto feature = static_cast<Feature>(i);
			std::unordered_set<uint32_t> unique_candidates;

			auto candidates = get_candidates_for_feature(feature);
			unique_candidates.insert(candidates.begin(), candidates.end());

			auto deps = get_feature_dependencies(feature);
			for (Feature d : deps)
			{
				candidates = get_candidates_for_feature(d);
				if (!candidates.empty())
					unique_candidates.insert(candidates.begin(), candidates.end());
			}

			for (uint32_t c : unique_candidates)
				++res.weights[static_cast<Candidate>(c)];
		}
	}

	return res;
}

CompilerHLSL::ShaderSubgroupSupportHelper::CandidateVector CompilerHLSL::ShaderSubgroupSupportHelper::
    get_candidates_for_feature(Feature ft, const Result &r)
{
	auto c = get_candidates_for_feature(ft);
	auto cmp = [&r](Candidate a, Candidate b) {
		if (r.weights[a] == r.weights[b])
			return a < b; // Prefer candidates with lower enum value
		return r.weights[a] > r.weights[b];
	};
	std::sort(c.begin(), c.end(), cmp);
	return c;
}

CompilerHLSL::ShaderSubgroupSupportHelper::CandidateVector CompilerHLSL::ShaderSubgroupSupportHelper::
    get_candidates_for_feature(Feature feature)
{
	switch (feature)
	{
	case SubgroupMask:
		return { KHR_shader_subgroup_ballot, NV_shader_thread_group, ARB_shader_ballot };
	case SubgroupSize:
		return { KHR_shader_subgroup_basic, NV_shader_thread_group, AMD_gcn_shader, ARB_shader_ballot };
	case SubgroupInvocationID:
		return { KHR_shader_subgroup_basic, NV_shader_thread_group, ARB_shader_ballot };
	case SubgroupID:
		return { KHR_shader_subgroup_basic, NV_shader_thread_group };
	case NumSubgroups:
		return { KHR_shader_subgroup_basic, NV_shader_thread_group };
	case SubgroupBroadcast_First:
		return { KHR_shader_subgroup_ballot, NV_shader_thread_shuffle, ARB_shader_ballot };
	case SubgroupBallotFindLSB_MSB:
		return { KHR_shader_subgroup_ballot, NV_shader_thread_group };
	case SubgroupAll_Any_AllEqualBool:
		return { KHR_shader_subgroup_vote, NV_gpu_shader_5, ARB_shader_group_vote, AMD_gcn_shader };
	case SubgroupAllEqualT:
		return {}; // depends on other features only
	case SubgroupElect:
		return {}; // depends on other features only
	case SubgroupBallot:
		return { KHR_shader_subgroup_ballot, NV_shader_thread_group, ARB_shader_ballot };
	case SubgroupBarrier:
		return { KHR_shader_subgroup_basic, NV_shader_thread_group, ARB_shader_ballot, AMD_gcn_shader };
	case SubgroupMemBarrier:
		return { KHR_shader_subgroup_basic };
	case SubgroupInverseBallot_InclBitCount_ExclBitCout:
		return {};
	case SubgroupBallotBitExtract:
		return { NV_shader_thread_group };
	case SubgroupBallotBitCount:
		return {};
	case SubgroupArithmeticIAddReduce:
	case SubgroupArithmeticIAddExclusiveScan:
	case SubgroupArithmeticIAddInclusiveScan:
	case SubgroupArithmeticFAddReduce:
	case SubgroupArithmeticFAddExclusiveScan:
	case SubgroupArithmeticFAddInclusiveScan:
	case SubgroupArithmeticIMulReduce:
	case SubgroupArithmeticIMulExclusiveScan:
	case SubgroupArithmeticIMulInclusiveScan:
	case SubgroupArithmeticFMulReduce:
	case SubgroupArithmeticFMulExclusiveScan:
	case SubgroupArithmeticFMulInclusiveScan:
		return { KHR_shader_subgroup_arithmetic, NV_shader_thread_shuffle };
	default:
		return {};
	}
}

CompilerHLSL::ShaderSubgroupSupportHelper::FeatureMask CompilerHLSL::ShaderSubgroupSupportHelper::build_mask(
    const SmallVector<Feature> &features)
{
	FeatureMask mask = 0;
	for (Feature f : features)
		mask |= FeatureMask(1) << f;
	return mask;
}

string CompilerHLSL::image_type_hlsl_modern(const SPIRType &type, uint32_t id)
{
	auto &imagetype = get<SPIRType>(type.image.type);
	const char *dim = nullptr;
	bool typed_load = false;
	uint32_t components = 4;

	bool force_image_srv = hlsl_options.nonwritable_uav_texture_as_srv && has_decoration(id, DecorationNonWritable);

	switch (type.image.dim)
	{
	case Dim1D:
		typed_load = type.image.sampled == 2;
		dim = "1D";
		break;
	case Dim2D:
		typed_load = type.image.sampled == 2;
		dim = "2D";
		break;
	case Dim3D:
		typed_load = type.image.sampled == 2;
		dim = "3D";
		break;
	case DimCube:
		if (type.image.sampled == 2)
			SPIRV_CROSS_THROW("RWTextureCube does not exist in HLSL.");
		dim = "Cube";
		break;
	case DimRect:
		SPIRV_CROSS_THROW("Rectangle texture support is not yet implemented for HLSL."); // TODO
	case DimBuffer:
		if (type.image.sampled == 1)
			return join("Buffer<", type_to_glsl(imagetype), components, ">");
		else if (type.image.sampled == 2)
		{
			if (interlocked_resources.count(id))
				return join("RasterizerOrderedBuffer<", image_format_to_type(type.image.format, imagetype.basetype),
				            ">");

			typed_load = !force_image_srv && type.image.sampled == 2;

			const char *rw = force_image_srv ? "" : "RW";
			return join(rw, "Buffer<",
			            typed_load ? image_format_to_type(type.image.format, imagetype.basetype) :
			                         join(type_to_glsl(imagetype), components),
			            ">");
		}
		else
			SPIRV_CROSS_THROW("Sampler buffers must be either sampled or unsampled. Cannot deduce in runtime.");
	case DimSubpassData:
		dim = "2D";
		typed_load = false;
		break;
	default:
		SPIRV_CROSS_THROW("Invalid dimension.");
	}
	const char *arrayed = type.image.arrayed ? "Array" : "";
	const char *ms = type.image.ms ? "MS" : "";
	const char *rw = typed_load && !force_image_srv ? "RW" : "";

	if (force_image_srv)
		typed_load = false;

	if (typed_load && interlocked_resources.count(id))
		rw = "RasterizerOrdered";

	return join(rw, "Texture", dim, ms, arrayed, "<",
	            typed_load ? image_format_to_type(type.image.format, imagetype.basetype) :
	                         join(type_to_glsl(imagetype), components),
	            ">");
}

// The optional id parameter indicates the object whose type we are trying
// to find the description for. It is optional. Most type descriptions do not
// depend on a specific object's use of that type.
string CompilerHLSL::type_to_glsl(const SPIRType &type, uint32_t id)
{
	// Ignore the pointer type since GLSL doesn't have pointers.

	switch (type.basetype)
	{
	case SPIRType::Struct:
		// Need OpName lookup here to get a "sensible" name for a struct.
		if (backend.explicit_struct_type)
			return join("struct ", to_name(type.self));
		else
			return to_name(type.self);

	case SPIRType::Image:
	case SPIRType::SampledImage:
		return image_type_hlsl(type, id);

	case SPIRType::Sampler:
		return comparison_ids.count(id) ? "SamplerComparisonState" : "SamplerState";

	case SPIRType::Void:
		return "void";

	default:
		break;
	}

	if (type.vecsize == 1 && type.columns == 1) // Scalar builtin
	{
		switch (type.basetype)
		{
		case SPIRType::Boolean:
			return "bool";
		case SPIRType::Int:
			return backend.basic_int_type;
		case SPIRType::UInt:
			return backend.basic_uint_type;
		case SPIRType::AtomicCounter:
			return "atomic_uint";
		case SPIRType::Half:
			if (hlsl_options.enable_16bit_types)
				return "half";
			else
				return "min16float";
		case SPIRType::Short:
			if (hlsl_options.enable_16bit_types)
				return "int16_t";
			else
				return "min16int";
		case SPIRType::UShort:
			if (hlsl_options.enable_16bit_types)
				return "uint16_t";
			else
				return "min16uint";
		case SPIRType::Float:
			return "float";
		case SPIRType::Double:
			return "double";
		case SPIRType::Int64:
			if (hlsl_options.shader_model < 60)
				SPIRV_CROSS_THROW("64-bit integers only supported in SM 6.0.");
			return "int64_t";
		case SPIRType::UInt64:
			if (hlsl_options.shader_model < 60)
				SPIRV_CROSS_THROW("64-bit integers only supported in SM 6.0.");
			return "uint64_t";
		case SPIRType::AccelerationStructure:
			return "RaytracingAccelerationStructure";
		case SPIRType::RayQuery:
			return "RayQuery<RAY_FLAG_NONE>";
		default:
			return "???";
		}
	}
	else if (type.vecsize > 1 && type.columns == 1) // Vector builtin
	{
		switch (type.basetype)
		{
		case SPIRType::Boolean:
			return join("bool", type.vecsize);
		case SPIRType::Int:
			return join("int", type.vecsize);
		case SPIRType::UInt:
			return join("uint", type.vecsize);
		case SPIRType::Half:
			return join(hlsl_options.enable_16bit_types ? "half" : "min16float", type.vecsize);
		case SPIRType::Short:
			return join(hlsl_options.enable_16bit_types ? "int16_t" : "min16int", type.vecsize);
		case SPIRType::UShort:
			return join(hlsl_options.enable_16bit_types ? "uint16_t" : "min16uint", type.vecsize);
		case SPIRType::Float:
			return join("float", type.vecsize);
		case SPIRType::Double:
			return join("double", type.vecsize);
		case SPIRType::Int64:
			return join("i64vec", type.vecsize);
		case SPIRType::UInt64:
			return join("u64vec", type.vecsize);
		default:
			return "???";
		}
	}
	else
	{
		switch (type.basetype)
		{
		case SPIRType::Boolean:
			return join("bool", type.columns, "x", type.vecsize);
		case SPIRType::Int:
			return join("int", type.columns, "x", type.vecsize);
		case SPIRType::UInt:
			return join("uint", type.columns, "x", type.vecsize);
		case SPIRType::Half:
			return join(hlsl_options.enable_16bit_types ? "half" : "min16float", type.columns, "x", type.vecsize);
		case SPIRType::Short:
			return join(hlsl_options.enable_16bit_types ? "int16_t" : "min16int", type.columns, "x", type.vecsize);
		case SPIRType::UShort:
			return join(hlsl_options.enable_16bit_types ? "uint16_t" : "min16uint", type.columns, "x", type.vecsize);
		case SPIRType::Float:
			return join("float", type.columns, "x", type.vecsize);
		case SPIRType::Double:
			return join("double", type.columns, "x", type.vecsize);
		// Matrix types not supported for int64/uint64.
		default:
			return "???";
		}
	}
}

void CompilerHLSL::emit_header()
{
	for (auto &header : header_lines)
		statement(header);

	if (header_lines.size() > 0)
	{
		statement("");
	}
}

void CompilerHLSL::emit_interface_block_globally(const SPIRVariable &var)
{
	add_resource_name(var.self);

	// The global copies of I/O variables should not contain interpolation qualifiers.
	// These are emitted inside the interface structs.
	auto &flags = ir.meta[var.self].decoration.decoration_flags;
	auto old_flags = flags;
	flags.reset();
	statement("static ", variable_decl(var), ";");
	flags = old_flags;
}

const char *CompilerHLSL::to_storage_qualifiers_glsl(const SPIRVariable &var)
{
	// Input and output variables are handled specially in HLSL backend.
	// The variables are declared as global, private variables, and do not need any qualifiers.
	if (var.storage == StorageClassUniformConstant || var.storage == StorageClassUniform ||
	    var.storage == StorageClassPushConstant)
	{
		return "uniform ";
	}

	return "";
}

void CompilerHLSL::emit_builtin_outputs_in_struct()
{
	auto &execution = get_entry_point();

	bool legacy = hlsl_options.shader_model <= 30;
	active_output_builtins.for_each_bit([&](uint32_t i) {
		const char *type = nullptr;
		const char *semantic = nullptr;
		auto builtin = static_cast<BuiltIn>(i);
		switch (builtin)
		{
		case BuiltInPosition:
			type = is_position_invariant() && backend.support_precise_qualifier ? "precise float4" : "float4";
			semantic = legacy ? "POSITION" : "SV_Position";
			break;

		case BuiltInSampleMask:
			if (hlsl_options.shader_model < 41 || execution.model != ExecutionModelFragment)
				SPIRV_CROSS_THROW("Sample Mask output is only supported in PS 4.1 or higher.");
			type = "uint";
			semantic = "SV_Coverage";
			break;

		case BuiltInFragDepth:
			type = "float";
			if (legacy)
			{
				semantic = "DEPTH";
			}
			else
			{
				if (hlsl_options.shader_model >= 50 && execution.flags.get(ExecutionModeDepthGreater))
					semantic = "SV_DepthGreaterEqual";
				else if (hlsl_options.shader_model >= 50 && execution.flags.get(ExecutionModeDepthLess))
					semantic = "SV_DepthLessEqual";
				else
					semantic = "SV_Depth";
			}
			break;

		case BuiltInClipDistance:
		{
			static const char *types[] = { "float", "float2", "float3", "float4" };

			// HLSL is a bit weird here, use SV_ClipDistance0, SV_ClipDistance1 and so on with vectors.
			if (execution.model == ExecutionModelMeshEXT)
			{
				if (clip_distance_count > 4)
					SPIRV_CROSS_THROW("Clip distance count > 4 not supported for mesh shaders.");

				if (clip_distance_count == 1)
				{
					// Avoids having to hack up access_chain code. Makes it trivially indexable.
					statement("float gl_ClipDistance[1] : SV_ClipDistance;");
				}
				else
				{
					// Replace array with vector directly, avoids any weird fixup path.
					statement(types[clip_distance_count - 1], " gl_ClipDistance : SV_ClipDistance;");
				}
			}
			else
			{
				for (uint32_t clip = 0; clip < clip_distance_count; clip += 4)
				{
					uint32_t to_declare = clip_distance_count - clip;
					if (to_declare > 4)
						to_declare = 4;

					uint32_t semantic_index = clip / 4;

					statement(types[to_declare - 1], " ", builtin_to_glsl(builtin, StorageClassOutput), semantic_index,
					          " : SV_ClipDistance", semantic_index, ";");
				}
			}
			break;
		}

		case BuiltInCullDistance:
		{
			static const char *types[] = { "float", "float2", "float3", "float4" };

			// HLSL is a bit weird here, use SV_CullDistance0, SV_CullDistance1 and so on with vectors.
			if (execution.model == ExecutionModelMeshEXT)
			{
				if (cull_distance_count > 4)
					SPIRV_CROSS_THROW("Cull distance count > 4 not supported for mesh shaders.");

				if (cull_distance_count == 1)
				{
					// Avoids having to hack up access_chain code. Makes it trivially indexable.
					statement("float gl_CullDistance[1] : SV_CullDistance;");
				}
				else
				{
					// Replace array with vector directly, avoids any weird fixup path.
					statement(types[cull_distance_count - 1], " gl_CullDistance : SV_CullDistance;");
				}
			}
			else
			{
				for (uint32_t cull = 0; cull < cull_distance_count; cull += 4)
				{
					uint32_t to_declare = cull_distance_count - cull;
					if (to_declare > 4)
						to_declare = 4;

					uint32_t semantic_index = cull / 4;

					statement(types[to_declare - 1], " ", builtin_to_glsl(builtin, StorageClassOutput), semantic_index,
					          " : SV_CullDistance", semantic_index, ";");
				}
			}
			break;
		}

		case BuiltInPointSize:
			// If point_size_compat is enabled, just ignore PointSize.
			// PointSize does not exist in HLSL, but some code bases might want to be able to use these shaders,
			// even if it means working around the missing feature.
			if (legacy)
			{
				type = "float";
				semantic = "PSIZE";
			}
			else if (!hlsl_options.point_size_compat)
				SPIRV_CROSS_THROW("Unsupported builtin in HLSL.");
			break;

		case BuiltInLayer:
		case BuiltInPrimitiveId:
		case BuiltInViewportIndex:
		case BuiltInPrimitiveShadingRateKHR:
		case BuiltInCullPrimitiveEXT:
			// per-primitive attributes handled separatly
			break;

		case BuiltInPrimitivePointIndicesEXT:
		case BuiltInPrimitiveLineIndicesEXT:
		case BuiltInPrimitiveTriangleIndicesEXT:
			// meshlet local-index buffer handled separatly
			break;

		default:
			SPIRV_CROSS_THROW("Unsupported builtin in HLSL.");
		}

		if (type && semantic)
			statement(type, " ", builtin_to_glsl(builtin, StorageClassOutput), " : ", semantic, ";");
	    });
}

void CompilerHLSL::emit_builtin_primitive_outputs_in_struct()
{
	active_output_builtins.for_each_bit([&](uint32_t i) {
		const char *type = nullptr;
		const char *semantic = nullptr;
		auto builtin = static_cast<BuiltIn>(i);
		switch (builtin)
		{
		case BuiltInLayer:
		{
			if (hlsl_options.shader_model < 50)
				SPIRV_CROSS_THROW("Render target array index output is only supported in SM 5.0 or higher.");
			type = "uint";
			semantic = "SV_RenderTargetArrayIndex";
			break;
		}

		case BuiltInPrimitiveId:
			type = "uint";
			semantic = "SV_PrimitiveID";
			break;

		case BuiltInViewportIndex:
			type = "uint";
			semantic = "SV_ViewportArrayIndex";
			break;

		case BuiltInPrimitiveShadingRateKHR:
			type = "uint";
			semantic = "SV_ShadingRate";
			break;

		case BuiltInCullPrimitiveEXT:
			type = "bool";
			semantic = "SV_CullPrimitive";
			break;

		default:
			break;
		}

		if (type && semantic)
			statement(type, " ", builtin_to_glsl(builtin, StorageClassOutput), " : ", semantic, ";");
	});
}

void CompilerHLSL::emit_builtin_inputs_in_struct()
{
	bool legacy = hlsl_options.shader_model <= 30;
	active_input_builtins.for_each_bit([&](uint32_t i) {
		const char *type = nullptr;
		const char *semantic = nullptr;
		auto builtin = static_cast<BuiltIn>(i);
		switch (builtin)
		{
		case BuiltInFragCoord:
			type = "float4";
			semantic = legacy ? "VPOS" : "SV_Position";
			break;

		case BuiltInVertexId:
		case BuiltInVertexIndex:
			if (legacy)
				SPIRV_CROSS_THROW("Vertex index not supported in SM 3.0 or lower.");
			type = "uint";
			semantic = "SV_VertexID";
			break;

		case BuiltInPrimitiveId:
			type = "uint";
			semantic = "SV_PrimitiveID";
			break;

		case BuiltInInstanceId:
		case BuiltInInstanceIndex:
			if (legacy)
				SPIRV_CROSS_THROW("Instance index not supported in SM 3.0 or lower.");
			type = "uint";
			semantic = "SV_InstanceID";
			break;

		case BuiltInSampleId:
			if (legacy)
				SPIRV_CROSS_THROW("Sample ID not supported in SM 3.0 or lower.");
			type = "uint";
			semantic = "SV_SampleIndex";
			break;

		case BuiltInSampleMask:
			if (hlsl_options.shader_model < 50 || get_entry_point().model != ExecutionModelFragment)
				SPIRV_CROSS_THROW("Sample Mask input is only supported in PS 5.0 or higher.");
			type = "uint";
			semantic = "SV_Coverage";
			break;

		case BuiltInGlobalInvocationId:
			type = "uint3";
			semantic = "SV_DispatchThreadID";
			break;

		case BuiltInLocalInvocationId:
			type = "uint3";
			semantic = "SV_GroupThreadID";
			break;

		case BuiltInLocalInvocationIndex:
			type = "uint";
			semantic = "SV_GroupIndex";
			break;

		case BuiltInWorkgroupId:
			type = "uint3";
			semantic = "SV_GroupID";
			break;

		case BuiltInFrontFacing:
			type = "bool";
			semantic = "SV_IsFrontFace";
			break;

		case BuiltInViewIndex:
			if (hlsl_options.shader_model < 61 || (get_entry_point().model != ExecutionModelVertex && get_entry_point().model != ExecutionModelFragment))
				SPIRV_CROSS_THROW("View Index input is only supported in VS and PS 6.1 or higher.");
			type = "uint";
			semantic = "SV_ViewID";
			break;

		case BuiltInNumWorkgroups:
		case BuiltInSubgroupSize:
		case BuiltInSubgroupLocalInvocationId:
		case BuiltInSubgroupEqMask:
		case BuiltInSubgroupLtMask:
		case BuiltInSubgroupLeMask:
		case BuiltInSubgroupGtMask:
		case BuiltInSubgroupGeMask:
		case BuiltInBaseVertex:
		case BuiltInBaseInstance:
			// Handled specially.
			break;

		case BuiltInHelperInvocation:
			if (hlsl_options.shader_model < 50 || get_entry_point().model != ExecutionModelFragment)
				SPIRV_CROSS_THROW("Helper Invocation input is only supported in PS 5.0 or higher.");
			break;

		case BuiltInClipDistance:
			// HLSL is a bit weird here, use SV_ClipDistance0, SV_ClipDistance1 and so on with vectors.
			for (uint32_t clip = 0; clip < clip_distance_count; clip += 4)
			{
				uint32_t to_declare = clip_distance_count - clip;
				if (to_declare > 4)
					to_declare = 4;

				uint32_t semantic_index = clip / 4;

				static const char *types[] = { "float", "float2", "float3", "float4" };
				statement(types[to_declare - 1], " ", builtin_to_glsl(builtin, StorageClassInput), semantic_index,
				          " : SV_ClipDistance", semantic_index, ";");
			}
			break;

		case BuiltInCullDistance:
			// HLSL is a bit weird here, use SV_CullDistance0, SV_CullDistance1 and so on with vectors.
			for (uint32_t cull = 0; cull < cull_distance_count; cull += 4)
			{
				uint32_t to_declare = cull_distance_count - cull;
				if (to_declare > 4)
					to_declare = 4;

				uint32_t semantic_index = cull / 4;

				static const char *types[] = { "float", "float2", "float3", "float4" };
				statement(types[to_declare - 1], " ", builtin_to_glsl(builtin, StorageClassInput), semantic_index,
				          " : SV_CullDistance", semantic_index, ";");
			}
			break;

		case BuiltInPointCoord:
			// PointCoord is not supported, but provide a way to just ignore that, similar to PointSize.
			if (hlsl_options.point_coord_compat)
				break;
			else
				SPIRV_CROSS_THROW("Unsupported builtin in HLSL.");

		case BuiltInLayer:
			if (hlsl_options.shader_model < 50 || get_entry_point().model != ExecutionModelFragment)
				SPIRV_CROSS_THROW("Render target array index input is only supported in PS 5.0 or higher.");
			type = "uint";
			semantic = "SV_RenderTargetArrayIndex";
			break;

		default:
			SPIRV_CROSS_THROW("Unsupported builtin in HLSL.");
		}

		if (type && semantic)
			statement(type, " ", builtin_to_glsl(builtin, StorageClassInput), " : ", semantic, ";");
	});
}

uint32_t CompilerHLSL::type_to_consumed_locations(const SPIRType &type) const
{
	// TODO: Need to verify correctness.
	uint32_t elements = 0;

	if (type.basetype == SPIRType::Struct)
	{
		for (uint32_t i = 0; i < uint32_t(type.member_types.size()); i++)
			elements += type_to_consumed_locations(get<SPIRType>(type.member_types[i]));
	}
	else
	{
		uint32_t array_multiplier = 1;
		for (uint32_t i = 0; i < uint32_t(type.array.size()); i++)
		{
			if (type.array_size_literal[i])
				array_multiplier *= type.array[i];
			else
				array_multiplier *= evaluate_constant_u32(type.array[i]);
		}
		elements += array_multiplier * type.columns;
	}
	return elements;
}

string CompilerHLSL::to_interpolation_qualifiers(const Bitset &flags)
{
	string res;
	//if (flags & (1ull << DecorationSmooth))
	//    res += "linear ";
	if (flags.get(DecorationFlat))
		res += "nointerpolation ";
	if (flags.get(DecorationNoPerspective))
		res += "noperspective ";
	if (flags.get(DecorationCentroid))
		res += "centroid ";
	if (flags.get(DecorationPatch))
		res += "patch "; // Seems to be different in actual HLSL.
	if (flags.get(DecorationSample))
		res += "sample ";
	if (flags.get(DecorationInvariant) && backend.support_precise_qualifier)
		res += "precise "; // Not supported?

	return res;
}

std::string CompilerHLSL::to_semantic(uint32_t location, ExecutionModel em, StorageClass sc)
{
	if (em == ExecutionModelVertex && sc == StorageClassInput)
	{
		// We have a vertex attribute - we should look at remapping it if the user provided
		// vertex attribute hints.
		for (auto &attribute : remap_vertex_attributes)
			if (attribute.location == location)
				return attribute.semantic;
	}

	// Not a vertex attribute, or no remap_vertex_attributes entry.
	return join("TEXCOORD", location);
}

void CompilerHLSL::emit_interface_block_in_struct(const SPIRVariable &var, unordered_set<uint32_t> &active_locations)
{
	auto &execution = get_entry_point();
	auto type = get<SPIRType>(var.basetype);

	string binding;
	bool use_location_number = true;
	bool need_matrix_unroll = false;
	bool legacy = hlsl_options.shader_model <= 30;
	if (execution.model == ExecutionModelFragment && var.storage == StorageClassOutput)
	{
		// Dual-source blending is achieved in HLSL by emitting to SV_Target0 and 1.
		uint32_t index = get_decoration(var.self, DecorationIndex);
		uint32_t location = get_decoration(var.self, DecorationLocation);

		if (index != 0 && location != 0)
			SPIRV_CROSS_THROW("Dual-source blending is only supported on MRT #0 in HLSL.");

		binding = join(legacy ? "COLOR" : "SV_Target", location + index);
		use_location_number = false;
		if (legacy) // COLOR must be a four-component vector on legacy shader model targets (HLSL ERR_COLOR_4COMP)
			type.vecsize = 4;
	}
	else if (var.storage == StorageClassInput && execution.model == ExecutionModelVertex)
	{
		need_matrix_unroll = true;
		if (legacy) // Inputs must be floating-point in legacy targets.
			type.basetype = SPIRType::Float;
	}

	const auto get_vacant_location = [&]() -> uint32_t {
		for (uint32_t i = 0; i < 64; i++)
			if (!active_locations.count(i))
				return i;
		SPIRV_CROSS_THROW("All locations from 0 to 63 are exhausted.");
	};

	auto name = to_name(var.self);
	if (use_location_number)
	{
		uint32_t location_number;

		// If an explicit location exists, use it with TEXCOORD[N] semantic.
		// Otherwise, pick a vacant location.
		if (has_decoration(var.self, DecorationLocation))
			location_number = get_decoration(var.self, DecorationLocation);
		else
			location_number = get_vacant_location();

		// Allow semantic remap if specified.
		auto semantic = to_semantic(location_number, execution.model, var.storage);

		if (need_matrix_unroll && type.columns > 1)
		{
			if (!type.array.empty())
				SPIRV_CROSS_THROW("Arrays of matrices used as input/output. This is not supported.");

			// Unroll matrices.
			for (uint32_t i = 0; i < type.columns; i++)
			{
				SPIRType newtype = type;
				newtype.columns = 1;

				string effective_semantic;
				if (hlsl_options.flatten_matrix_vertex_input_semantics)
					effective_semantic = to_semantic(location_number, execution.model, var.storage);
				else
					effective_semantic = join(semantic, "_", i);

				statement(to_interpolation_qualifiers(get_decoration_bitset(var.self)),
				          variable_decl(newtype, join(name, "_", i)), " : ", effective_semantic, ";");
				active_locations.insert(location_number++);
			}
		}
		else
		{
			auto decl_type = type;
			if (execution.model == ExecutionModelMeshEXT)
			{
				decl_type.array.erase(decl_type.array.begin());
				decl_type.array_size_literal.erase(decl_type.array_size_literal.begin());
			}
			statement(to_interpolation_qualifiers(get_decoration_bitset(var.self)), variable_decl(decl_type, name), " : ",
			          semantic, ";");

			// Structs and arrays should consume more locations.
			uint32_t consumed_locations = type_to_consumed_locations(decl_type);
			for (uint32_t i = 0; i < consumed_locations; i++)
				active_locations.insert(location_number + i);
		}
	}
	else
	{
		statement(variable_decl(type, name), " : ", binding, ";");
	}
}

std::string CompilerHLSL::builtin_to_glsl(spv::BuiltIn builtin, spv::StorageClass storage)
{
	switch (builtin)
	{
	case BuiltInVertexId:
		return "gl_VertexID";
	case BuiltInInstanceId:
		return "gl_InstanceID";
	case BuiltInNumWorkgroups:
	{
		if (!num_workgroups_builtin)
			SPIRV_CROSS_THROW("NumWorkgroups builtin is used, but remap_num_workgroups_builtin() was not called. "
			                  "Cannot emit code for this builtin.");

		auto &var = get<SPIRVariable>(num_workgroups_builtin);
		auto &type = get<SPIRType>(var.basetype);
		auto ret = join(to_name(num_workgroups_builtin), "_", get_member_name(type.self, 0));
		ParsedIR::sanitize_underscores(ret);
		return ret;
	}
	case BuiltInPointCoord:
		// Crude hack, but there is no real alternative. This path is only enabled if point_coord_compat is set.
		return "float2(0.5f, 0.5f)";
	case BuiltInSubgroupLocalInvocationId:
		return "WaveGetLaneIndex()";
	case BuiltInSubgroupSize:
		return "WaveGetLaneCount()";
	case BuiltInHelperInvocation:
		return "IsHelperLane()";

	default:
		return CompilerGLSL_builtin_to_glsl(builtin, storage);
	}
}

void CompilerHLSL::emit_builtin_variables()
{
	Bitset builtins = active_input_builtins;
	builtins.merge_or(active_output_builtins);

	std::unordered_map<uint32_t, ID> builtin_to_initializer;
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		if (!is_builtin_variable(var) || var.storage != StorageClassOutput || !var.initializer)
			return;

		auto *c = this->maybe_get<SPIRConstant>(var.initializer);
		if (!c)
			return;

		auto &type = this->get<SPIRType>(var.basetype);
		if (type.basetype == SPIRType::Struct)
		{
			uint32_t member_count = uint32_t(type.member_types.size());
			for (uint32_t i = 0; i < member_count; i++)
			{
				if (has_member_decoration(type.self, i, DecorationBuiltIn))
				{
					builtin_to_initializer[get_member_decoration(type.self, i, DecorationBuiltIn)] =
						c->subconstants[i];
				}
			}
		}
		else if (has_decoration(var.self, DecorationBuiltIn))
			builtin_to_initializer[get_decoration(var.self, DecorationBuiltIn)] = var.initializer;
	});

	// Emit global variables for the interface variables which are statically used by the shader.
	builtins.for_each_bit([&](uint32_t i) {
		const char *type = nullptr;
		auto builtin = static_cast<BuiltIn>(i);
		uint32_t array_size = 0;

		string init_expr;
		auto init_itr = builtin_to_initializer.find(builtin);
		if (init_itr != builtin_to_initializer.end())
			init_expr = join(" = ", to_expression(init_itr->second));

		if (get_execution_model() == ExecutionModelMeshEXT)
		{
			if (builtin == BuiltInPosition || builtin == BuiltInPointSize || builtin == BuiltInClipDistance ||
			    builtin == BuiltInCullDistance || builtin == BuiltInLayer || builtin == BuiltInPrimitiveId ||
			    builtin == BuiltInViewportIndex || builtin == BuiltInCullPrimitiveEXT ||
			    builtin == BuiltInPrimitiveShadingRateKHR || builtin == BuiltInPrimitivePointIndicesEXT ||
			    builtin == BuiltInPrimitiveLineIndicesEXT || builtin == BuiltInPrimitiveTriangleIndicesEXT)
			{
				return;
			}
		}

		switch (builtin)
		{
		case BuiltInFragCoord:
		case BuiltInPosition:
			type = "float4";
			break;

		case BuiltInFragDepth:
			type = "float";
			break;

		case BuiltInVertexId:
		case BuiltInVertexIndex:
		case BuiltInInstanceIndex:
			type = "int";
			if (hlsl_options.support_nonzero_base_vertex_base_instance)
				base_vertex_info.used = true;
			break;

		case BuiltInBaseVertex:
		case BuiltInBaseInstance:
			type = "int";
			base_vertex_info.used = true;
			break;

		case BuiltInInstanceId:
		case BuiltInSampleId:
			type = "int";
			break;

		case BuiltInPointSize:
			if (hlsl_options.point_size_compat || hlsl_options.shader_model <= 30)
			{
				// Just emit the global variable, it will be ignored.
				type = "float";
				break;
			}
			else
				SPIRV_CROSS_THROW(join("Unsupported builtin in HLSL: ", unsigned(builtin)));

		case BuiltInGlobalInvocationId:
		case BuiltInLocalInvocationId:
		case BuiltInWorkgroupId:
			type = "uint3";
			break;

		case BuiltInLocalInvocationIndex:
			type = "uint";
			break;

		case BuiltInFrontFacing:
			type = "bool";
			break;

		case BuiltInNumWorkgroups:
		case BuiltInPointCoord:
			// Handled specially.
			break;

		case BuiltInSubgroupLocalInvocationId:
		case BuiltInSubgroupSize:
			if (hlsl_options.shader_model < 60)
				SPIRV_CROSS_THROW("Need SM 6.0 for Wave ops.");
			break;

		case BuiltInSubgroupEqMask:
		case BuiltInSubgroupLtMask:
		case BuiltInSubgroupLeMask:
		case BuiltInSubgroupGtMask:
		case BuiltInSubgroupGeMask:
			if (hlsl_options.shader_model < 60)
				SPIRV_CROSS_THROW("Need SM 6.0 for Wave ops.");
			type = "uint4";
			break;

		case BuiltInHelperInvocation:
			if (hlsl_options.shader_model < 50)
				SPIRV_CROSS_THROW("Need SM 5.0 for Helper Invocation.");
			break;

		case BuiltInClipDistance:
			array_size = clip_distance_count;
			type = "float";
			break;

		case BuiltInCullDistance:
			array_size = cull_distance_count;
			type = "float";
			break;

		case BuiltInSampleMask:
			type = "int";
			break;

		case BuiltInPrimitiveId:
		case BuiltInViewIndex:
		case BuiltInLayer:
			type = "uint";
			break;

		case BuiltInViewportIndex:
		case BuiltInPrimitiveShadingRateKHR:
		case BuiltInPrimitiveLineIndicesEXT:
		case BuiltInCullPrimitiveEXT:
			type = "uint";
			break;

		default:
			SPIRV_CROSS_THROW(join("Unsupported builtin in HLSL: ", unsigned(builtin)));
		}

		StorageClass storage = active_input_builtins.get(i) ? StorageClassInput : StorageClassOutput;

		if (type)
		{
			if (array_size)
				statement("static ", type, " ", builtin_to_glsl(builtin, storage), "[", array_size, "]", init_expr, ";");
			else
				statement("static ", type, " ", builtin_to_glsl(builtin, storage), init_expr, ";");
		}

		// SampleMask can be both in and out with sample builtin, in this case we have already
		// declared the input variable and we need to add the output one now.
		if (builtin == BuiltInSampleMask && storage == StorageClassInput && this->active_output_builtins.get(i))
		{
			statement("static ", type, " ", this->builtin_to_glsl(builtin, StorageClassOutput), init_expr, ";");
		}
	});

	if (base_vertex_info.used)
	{
		string binding_info;
		if (base_vertex_info.explicit_binding)
		{
			binding_info = join(" : register(b", base_vertex_info.register_index);
			if (base_vertex_info.register_space)
				binding_info += join(", space", base_vertex_info.register_space);
			binding_info += ")";
		}
		statement("cbuffer SPIRV_Cross_VertexInfo", binding_info);
		begin_scope();
		statement("int SPIRV_Cross_BaseVertex;");
		statement("int SPIRV_Cross_BaseInstance;");
		end_scope_decl();
		statement("");
	}
}

void CompilerHLSL::emit_composite_constants()
{
	// HLSL cannot declare structs or arrays inline, so we must move them out to
	// global constants directly.
	bool emitted = false;

	ir.for_each_typed_id<SPIRConstant>([&](uint32_t, SPIRConstant &c) {
		if (c.specialization)
			return;

		auto &type = this->get<SPIRType>(c.constant_type);

		if (type.basetype == SPIRType::Struct && is_builtin_type(type))
			return;

		if (type.basetype == SPIRType::Struct || !type.array.empty())
		{
			add_resource_name(c.self);
			auto name = to_name(c.self);
			statement("static const ", variable_decl(type, name), " = ", constant_expression(c), ";");
			emitted = true;
		}
	});

	if (emitted)
		statement("");
}

void CompilerHLSL::emit_specialization_constants_and_structs()
{
	bool emitted = false;
	SpecializationConstant wg_x, wg_y, wg_z;
	ID workgroup_size_id = get_work_group_size_specialization_constants(wg_x, wg_y, wg_z);

	std::unordered_set<TypeID> io_block_types;
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, const SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);
		if ((var.storage == StorageClassInput || var.storage == StorageClassOutput) &&
		    !var.remapped_variable && type.pointer && !is_builtin_variable(var) &&
		    interface_variable_exists_in_entry_point(var.self) &&
		    has_decoration(type.self, DecorationBlock))
		{
			io_block_types.insert(type.self);
		}
	});

	auto loop_lock = ir.create_loop_hard_lock();
	for (auto &id_ : ir.ids_for_constant_undef_or_type)
	{
		auto &id = ir.ids[id_];

		if (id.get_type() == TypeConstant)
		{
			auto &c = id.get<SPIRConstant>();

			if (c.self == workgroup_size_id)
			{
				statement("static const uint3 gl_WorkGroupSize = ",
				          constant_expression(get<SPIRConstant>(workgroup_size_id)), ";");
				emitted = true;
			}
			else if (c.specialization)
			{
				auto &type = get<SPIRType>(c.constant_type);
				add_resource_name(c.self);
				auto name = to_name(c.self);

				if (has_decoration(c.self, DecorationSpecId))
				{
					// HLSL does not support specialization constants, so fallback to macros.
					c.specialization_constant_macro_name =
							constant_value_macro_name(get_decoration(c.self, DecorationSpecId));

					statement("#ifndef ", c.specialization_constant_macro_name);
					statement("#define ", c.specialization_constant_macro_name, " ", constant_expression(c));
					statement("#endif");
					statement("static const ", variable_decl(type, name), " = ", c.specialization_constant_macro_name, ";");
				}
				else
					statement("static const ", variable_decl(type, name), " = ", constant_expression(c), ";");

				emitted = true;
			}
		}
		else if (id.get_type() == TypeConstantOp)
		{
			auto &c = id.get<SPIRConstantOp>();
			auto &type = get<SPIRType>(c.basetype);
			add_resource_name(c.self);
			auto name = to_name(c.self);
			statement("static const ", variable_decl(type, name), " = ", constant_op_expression(c), ";");
			emitted = true;
		}
		else if (id.get_type() == TypeType)
		{
			auto &type = id.get<SPIRType>();
			bool is_non_io_block = has_decoration(type.self, DecorationBlock) &&
			                       io_block_types.count(type.self) == 0;
			bool is_buffer_block = has_decoration(type.self, DecorationBufferBlock);
			if (type.basetype == SPIRType::Struct && type.array.empty() &&
			    !type.pointer && !is_non_io_block && !is_buffer_block)
			{
				if (emitted)
					statement("");
				emitted = false;

				emit_struct(type);
			}
		}
		else if (id.get_type() == TypeUndef)
		{
			auto &undef = id.get<SPIRUndef>();
			auto &type = this->get<SPIRType>(undef.basetype);
			// OpUndef can be void for some reason ...
			if (type.basetype == SPIRType::Void)
				return;

			string initializer;
			if (options.force_zero_initialized_variables && type_can_zero_initialize(type))
				initializer = join(" = ", to_zero_initialized_expression(undef.basetype));

			statement("static ", variable_decl(type, to_name(undef.self), undef.self), initializer, ";");
			emitted = true;
		}
	}

	if (emitted)
		statement("");
}

void CompilerHLSL::replace_illegal_names()
{
	static const unordered_set<string> keywords = {
		// Additional HLSL specific keywords.
		// From https://docs.microsoft.com/en-US/windows/win32/direct3dhlsl/dx-graphics-hlsl-appendix-keywords
		"AppendStructuredBuffer", "asm", "asm_fragment",
		"BlendState", "bool", "break", "Buffer", "ByteAddressBuffer",
		"case", "cbuffer", "centroid", "class", "column_major", "compile",
		"compile_fragment", "CompileShader", "const", "continue", "ComputeShader",
		"ConsumeStructuredBuffer",
		"default", "DepthStencilState", "DepthStencilView", "discard", "do",
		"double", "DomainShader", "dword",
		"else", "export", "false", "float", "for", "fxgroup",
		"GeometryShader", "groupshared", "half", "HullShader",
		"indices", "if", "in", "inline", "inout", "InputPatch", "int", "interface",
		"line", "lineadj", "linear", "LineStream",
		"matrix", "min16float", "min10float", "min16int", "min16uint",
		"namespace", "nointerpolation", "noperspective", "NULL",
		"out", "OutputPatch",
		"payload", "packoffset", "pass", "pixelfragment", "PixelShader", "point",
		"PointStream", "precise", "RasterizerState", "RenderTargetView",
		"return", "register", "row_major", "RWBuffer", "RWByteAddressBuffer",
		"RWStructuredBuffer", "RWTexture1D", "RWTexture1DArray", "RWTexture2D",
		"RWTexture2DArray", "RWTexture3D", "sample", "sampler", "SamplerState",
		"SamplerComparisonState", "shared", "snorm", "stateblock", "stateblock_state",
		"static", "string", "struct", "switch", "StructuredBuffer", "tbuffer",
		"technique", "technique10", "technique11", "texture", "Texture1D",
		"Texture1DArray", "Texture2D", "Texture2DArray", "Texture2DMS", "Texture2DMSArray",
		"Texture3D", "TextureCube", "TextureCubeArray", "true", "typedef", "triangle",
		"triangleadj", "TriangleStream", "uint", "uniform", "unorm", "unsigned",
		"vector", "vertexfragment", "VertexShader", "vertices", "void", "volatile", "while",
	};

	CompilerGLSL_replace_illegal_names(keywords);
	CompilerGLSL_replace_illegal_names();
}

void CompilerHLSL::emit_resources()
{
	auto &execution = get_entry_point();

	replace_illegal_names();

	switch (execution.model)
	{
	case ExecutionModelGeometry:
	case ExecutionModelTessellationControl:
	case ExecutionModelTessellationEvaluation:
	case ExecutionModelMeshEXT:
		fixup_implicit_builtin_block_names(execution.model);
		break;

	default:
		break;
	}

	emit_specialization_constants_and_structs();
	emit_composite_constants();

	bool emitted = false;

	// Output UBOs and SSBOs
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);

		bool is_block_storage = type.storage == StorageClassStorageBuffer || type.storage == StorageClassUniform;
		bool has_block_flags = ir.meta[type.self].decoration.decoration_flags.get(DecorationBlock) ||
		                       ir.meta[type.self].decoration.decoration_flags.get(DecorationBufferBlock);

		if (var.storage != StorageClassFunction && type.pointer && is_block_storage && !is_hidden_variable(var) &&
		    has_block_flags)
		{
			emit_buffer_block(var);
			emitted = true;
		}
	});

	// Output push constant blocks
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);
		if (var.storage != StorageClassFunction && type.pointer && type.storage == StorageClassPushConstant &&
		    !is_hidden_variable(var))
		{
			emit_push_constant_block(var);
			emitted = true;
		}
	});

	if (execution.model == ExecutionModelVertex && hlsl_options.shader_model <= 30 &&
	    active_output_builtins.get(BuiltInPosition))
	{
		statement("uniform float4 gl_HalfPixel;");
		emitted = true;
	}

	bool skip_separate_image_sampler = !combined_image_samplers.empty() || hlsl_options.shader_model <= 30;

	// Output Uniform Constants (values, samplers, images, etc).
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);

		// If we're remapping separate samplers and images, only emit the combined samplers.
		if (skip_separate_image_sampler)
		{
			// Sampler buffers are always used without a sampler, and they will also work in regular D3D.
			bool sampler_buffer = type.basetype == SPIRType::Image && type.image.dim == DimBuffer;
			bool separate_image = type.basetype == SPIRType::Image && type.image.sampled == 1;
			bool separate_sampler = type.basetype == SPIRType::Sampler;
			if (!sampler_buffer && (separate_image || separate_sampler))
				return;
		}

		if (var.storage != StorageClassFunction && !is_builtin_variable(var) && !var.remapped_variable &&
		    type.pointer && (type.storage == StorageClassUniformConstant || type.storage == StorageClassAtomicCounter) &&
		    !is_hidden_variable(var))
		{
			emit_uniform(var);
			emitted = true;
		}
	});

	if (emitted)
		statement("");
	emitted = false;

	// Emit builtin input and output variables here.
	emit_builtin_variables();

	if (execution.model != ExecutionModelMeshEXT)
	{
		ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
			auto &type = this->get<SPIRType>(var.basetype);

			if (var.storage != StorageClassFunction && !var.remapped_variable && type.pointer &&
			   (var.storage == StorageClassInput || var.storage == StorageClassOutput) && !is_builtin_variable(var) &&
			   interface_variable_exists_in_entry_point(var.self))
			{
				// Builtin variables are handled separately.
				emit_interface_block_globally(var);
				emitted = true;
			}
		});
	}

	if (emitted)
		statement("");
	emitted = false;

	require_input = false;
	require_output = false;
	unordered_set<uint32_t> active_inputs;
	unordered_set<uint32_t> active_outputs;

	struct IOVariable
	{
		const SPIRVariable *var;
		uint32_t location;
		uint32_t block_member_index;
		bool block;
	};

	SmallVector<IOVariable> input_variables;
	SmallVector<IOVariable> output_variables;

	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);
		bool block = has_decoration(type.self, DecorationBlock);

		if (var.storage != StorageClassInput && var.storage != StorageClassOutput)
			return;

		if (!var.remapped_variable && type.pointer && !is_builtin_variable(var) &&
		    interface_variable_exists_in_entry_point(var.self))
		{
			if (block)
			{
				for (uint32_t i = 0; i < uint32_t(type.member_types.size()); i++)
				{
					uint32_t location = get_declared_member_location(var, i, false);
					if (var.storage == StorageClassInput)
						input_variables.push_back({ &var, location, i, true });
					else
						output_variables.push_back({ &var, location, i, true });
				}
			}
			else
			{
				uint32_t location = get_decoration(var.self, DecorationLocation);
				if (var.storage == StorageClassInput)
					input_variables.push_back({ &var, location, 0, false });
				else
					output_variables.push_back({ &var, location, 0, false });
			}
		}
	});

	const auto variable_compare = [&](const IOVariable &a, const IOVariable &b) -> bool {
		// Sort input and output variables based on, from more robust to less robust:
		// - Location
		// - Variable has a location
		// - Name comparison
		// - Variable has a name
		// - Fallback: ID
		bool has_location_a = a.block || has_decoration(a.var->self, DecorationLocation);
		bool has_location_b = b.block || has_decoration(b.var->self, DecorationLocation);

		if (has_location_a && has_location_b)
			return a.location < b.location;
		else if (has_location_a && !has_location_b)
			return true;
		else if (!has_location_a && has_location_b)
			return false;

		const auto &name1 = to_name(a.var->self);
		const auto &name2 = to_name(b.var->self);

		if (name1.empty() && name2.empty())
			return a.var->self < b.var->self;
		else if (name1.empty())
			return true;
		else if (name2.empty())
			return false;

		return name1.compare(name2) < 0;
	};

	auto input_builtins = active_input_builtins;
	input_builtins.clear(BuiltInNumWorkgroups);
	input_builtins.clear(BuiltInPointCoord);
	input_builtins.clear(BuiltInSubgroupSize);
	input_builtins.clear(BuiltInSubgroupLocalInvocationId);
	input_builtins.clear(BuiltInSubgroupEqMask);
	input_builtins.clear(BuiltInSubgroupLtMask);
	input_builtins.clear(BuiltInSubgroupLeMask);
	input_builtins.clear(BuiltInSubgroupGtMask);
	input_builtins.clear(BuiltInSubgroupGeMask);

	if (!input_variables.empty() || !input_builtins.empty())
	{
		require_input = true;
		statement("struct SPIRV_Cross_Input");

		begin_scope();
		sort(input_variables.begin(), input_variables.end(), variable_compare);
		for (auto &var : input_variables)
		{
			if (var.block)
				emit_interface_block_member_in_struct(*var.var, var.block_member_index, var.location, active_inputs);
			else
				emit_interface_block_in_struct(*var.var, active_inputs);
		}
		emit_builtin_inputs_in_struct();
		end_scope_decl();
		statement("");
	}

	const bool is_mesh_shader = execution.model == ExecutionModelMeshEXT;
	if (!output_variables.empty() || !active_output_builtins.empty())
	{
		sort(output_variables.begin(), output_variables.end(), variable_compare);
		require_output = !is_mesh_shader;

		statement(is_mesh_shader ? "struct gl_MeshPerVertexEXT" : "struct SPIRV_Cross_Output");
		begin_scope();
		for (auto &var : output_variables)
		{
			if (is_per_primitive_variable(*var.var))
				continue;
			if (var.block && is_mesh_shader && var.block_member_index != 0)
				continue;
			if (var.block && !is_mesh_shader)
				emit_interface_block_member_in_struct(*var.var, var.block_member_index, var.location, active_outputs);
			else
				emit_interface_block_in_struct(*var.var, active_outputs);
		}
		emit_builtin_outputs_in_struct();
		if (!is_mesh_shader)
			emit_builtin_primitive_outputs_in_struct();
		end_scope_decl();
		statement("");

		if (is_mesh_shader)
		{
			statement("struct gl_MeshPerPrimitiveEXT");
			begin_scope();
			for (auto &var : output_variables)
			{
				if (!is_per_primitive_variable(*var.var))
					continue;
				if (var.block && var.block_member_index != 0)
					continue;

				emit_interface_block_in_struct(*var.var, active_outputs);
			}
			emit_builtin_primitive_outputs_in_struct();
			end_scope_decl();
			statement("");
		}
	}

	// Global variables.
	for (auto global : global_variables)
	{
		auto &var = get<SPIRVariable>(global);
		if (is_hidden_variable(var, true))
			continue;

		if (var.storage == StorageClassTaskPayloadWorkgroupEXT && is_mesh_shader)
			continue;

		if (var.storage != StorageClassOutput)
		{
			if (!variable_is_lut(var))
			{
				add_resource_name(var.self);

				const char *storage = nullptr;
				switch (var.storage)
				{
				case StorageClassWorkgroup:
				case StorageClassTaskPayloadWorkgroupEXT:
					storage = "groupshared";
					break;

				default:
					storage = "static";
					break;
				}

				string initializer;
				if (options.force_zero_initialized_variables && var.storage == StorageClassPrivate &&
				    !var.initializer && !var.static_expression && type_can_zero_initialize(get_variable_data_type(var)))
				{
					initializer = join(" = ", to_zero_initialized_expression(get_variable_data_type_id(var)));
				}
				statement(storage, " ", variable_decl(var), initializer, ";");

				emitted = true;
			}
		}
	}

	if (emitted)
		statement("");

	if (requires_op_fmod)
	{
		static const char *types[] = {
			"float",
			"float2",
			"float3",
			"float4",
		};

		for (auto &type : types)
		{
			statement(type, " mod(", type, " x, ", type, " y)");
			begin_scope();
			statement("return x - y * floor(x / y);");
			end_scope();
			statement("");
		}
	}

	emit_texture_size_variants(required_texture_size_variants.srv, "4", false, "");
	for (uint32_t norm = 0; norm < 3; norm++)
	{
		for (uint32_t comp = 0; comp < 4; comp++)
		{
			static const char *qualifiers[] = { "", "unorm ", "snorm " };
			static const char *vecsizes[] = { "", "2", "3", "4" };
			emit_texture_size_variants(required_texture_size_variants.uav[norm][comp], vecsizes[comp], true,
			                           qualifiers[norm]);
		}
	}

#ifndef SPIRV_CROSS_WEBMIN
	if (requires_fp16_packing)
	{
		// HLSL does not pack into a single word sadly :(
		statement("uint spvPackHalf2x16(float2 value)");
		begin_scope();
		statement("uint2 Packed = f32tof16(value);");
		statement("return Packed.x | (Packed.y << 16);");
		end_scope();
		statement("");

		statement("float2 spvUnpackHalf2x16(uint value)");
		begin_scope();
		statement("return f16tof32(uint2(value & 0xffff, value >> 16));");
		end_scope();
		statement("");
	}

	if (requires_uint2_packing)
	{
		statement("uint64_t spvPackUint2x32(uint2 value)");
		begin_scope();
		statement("return (uint64_t(value.y) << 32) | uint64_t(value.x);");
		end_scope();
		statement("");

		statement("uint2 spvUnpackUint2x32(uint64_t value)");
		begin_scope();
		statement("uint2 Unpacked;");
		statement("Unpacked.x = uint(value & 0xffffffff);");
		statement("Unpacked.y = uint(value >> 32);");
		statement("return Unpacked;");
		end_scope();
		statement("");
	}

	if (requires_explicit_fp16_packing)
	{
		// HLSL does not pack into a single word sadly :(
		statement("uint spvPackFloat2x16(min16float2 value)");
		begin_scope();
		statement("uint2 Packed = f32tof16(value);");
		statement("return Packed.x | (Packed.y << 16);");
		end_scope();
		statement("");

		statement("min16float2 spvUnpackFloat2x16(uint value)");
		begin_scope();
		statement("return min16float2(f16tof32(uint2(value & 0xffff, value >> 16)));");
		end_scope();
		statement("");
	}

	// HLSL does not seem to have builtins for these operation, so roll them by hand ...
	if (requires_unorm8_packing)
	{
		statement("uint spvPackUnorm4x8(float4 value)");
		begin_scope();
		statement("uint4 Packed = uint4(round(saturate(value) * 255.0));");
		statement("return Packed.x | (Packed.y << 8) | (Packed.z << 16) | (Packed.w << 24);");
		end_scope();
		statement("");

		statement("float4 spvUnpackUnorm4x8(uint value)");
		begin_scope();
		statement("uint4 Packed = uint4(value & 0xff, (value >> 8) & 0xff, (value >> 16) & 0xff, value >> 24);");
		statement("return float4(Packed) / 255.0;");
		end_scope();
		statement("");
	}

	if (requires_snorm8_packing)
	{
		statement("uint spvPackSnorm4x8(float4 value)");
		begin_scope();
		statement("int4 Packed = int4(round(clamp(value, -1.0, 1.0) * 127.0)) & 0xff;");
		statement("return uint(Packed.x | (Packed.y << 8) | (Packed.z << 16) | (Packed.w << 24));");
		end_scope();
		statement("");

		statement("float4 spvUnpackSnorm4x8(uint value)");
		begin_scope();
		statement("int SignedValue = int(value);");
		statement("int4 Packed = int4(SignedValue << 24, SignedValue << 16, SignedValue << 8, SignedValue) >> 24;");
		statement("return clamp(float4(Packed) / 127.0, -1.0, 1.0);");
		end_scope();
		statement("");
	}

	if (requires_unorm16_packing)
	{
		statement("uint spvPackUnorm2x16(float2 value)");
		begin_scope();
		statement("uint2 Packed = uint2(round(saturate(value) * 65535.0));");
		statement("return Packed.x | (Packed.y << 16);");
		end_scope();
		statement("");

		statement("float2 spvUnpackUnorm2x16(uint value)");
		begin_scope();
		statement("uint2 Packed = uint2(value & 0xffff, value >> 16);");
		statement("return float2(Packed) / 65535.0;");
		end_scope();
		statement("");
	}

	if (requires_snorm16_packing)
	{
		statement("uint spvPackSnorm2x16(float2 value)");
		begin_scope();
		statement("int2 Packed = int2(round(clamp(value, -1.0, 1.0) * 32767.0)) & 0xffff;");
		statement("return uint(Packed.x | (Packed.y << 16));");
		end_scope();
		statement("");

		statement("float2 spvUnpackSnorm2x16(uint value)");
		begin_scope();
		statement("int SignedValue = int(value);");
		statement("int2 Packed = int2(SignedValue << 16, SignedValue) >> 16;");
		statement("return clamp(float2(Packed) / 32767.0, -1.0, 1.0);");
		end_scope();
		statement("");
	}

	if (requires_bitfield_insert)
	{
		static const char *types[] = { "uint", "uint2", "uint3", "uint4" };
		for (auto &type : types)
		{
			statement(type, " spvBitfieldInsert(", type, " Base, ", type, " Insert, uint Offset, uint Count)");
			begin_scope();
			statement("uint Mask = Count == 32 ? 0xffffffff : (((1u << Count) - 1) << (Offset & 31));");
			statement("return (Base & ~Mask) | ((Insert << Offset) & Mask);");
			end_scope();
			statement("");
		}
	}

	if (requires_bitfield_extract)
	{
		static const char *unsigned_types[] = { "uint", "uint2", "uint3", "uint4" };
		for (auto &type : unsigned_types)
		{
			statement(type, " spvBitfieldUExtract(", type, " Base, uint Offset, uint Count)");
			begin_scope();
			statement("uint Mask = Count == 32 ? 0xffffffff : ((1 << Count) - 1);");
			statement("return (Base >> Offset) & Mask;");
			end_scope();
			statement("");
		}

		// In this overload, we will have to do sign-extension, which we will emulate by shifting up and down.
		static const char *signed_types[] = { "int", "int2", "int3", "int4" };
		for (auto &type : signed_types)
		{
			statement(type, " spvBitfieldSExtract(", type, " Base, int Offset, int Count)");
			begin_scope();
			statement("int Mask = Count == 32 ? -1 : ((1 << Count) - 1);");
			statement(type, " Masked = (Base >> Offset) & Mask;");
			statement("int ExtendShift = (32 - Count) & 31;");
			statement("return (Masked << ExtendShift) >> ExtendShift;");
			end_scope();
			statement("");
		}
	}

	if (requires_inverse_2x2)
	{
		statement("// Returns the inverse of a matrix, by using the algorithm of calculating the classical");
		statement("// adjoint and dividing by the determinant. The contents of the matrix are changed.");
		statement("float2x2 spvInverse(float2x2 m)");
		begin_scope();
		statement("float2x2 adj;	// The adjoint matrix (inverse after dividing by determinant)");
		statement_no_indent("");
		statement("// Create the transpose of the cofactors, as the classical adjoint of the matrix.");
		statement("adj[0][0] =  m[1][1];");
		statement("adj[0][1] = -m[0][1];");
		statement_no_indent("");
		statement("adj[1][0] = -m[1][0];");
		statement("adj[1][1] =  m[0][0];");
		statement_no_indent("");
		statement("// Calculate the determinant as a combination of the cofactors of the first row.");
		statement("float det = (adj[0][0] * m[0][0]) + (adj[0][1] * m[1][0]);");
		statement_no_indent("");
		statement("// Divide the classical adjoint matrix by the determinant.");
		statement("// If determinant is zero, matrix is not invertable, so leave it unchanged.");
		statement("return (det != 0.0f) ? (adj * (1.0f / det)) : m;");
		end_scope();
		statement("");
	}

	if (requires_inverse_3x3)
	{
		statement("// Returns the determinant of a 2x2 matrix.");
		statement("float spvDet2x2(float a1, float a2, float b1, float b2)");
		begin_scope();
		statement("return a1 * b2 - b1 * a2;");
		end_scope();
		statement_no_indent("");
		statement("// Returns the inverse of a matrix, by using the algorithm of calculating the classical");
		statement("// adjoint and dividing by the determinant. The contents of the matrix are changed.");
		statement("float3x3 spvInverse(float3x3 m)");
		begin_scope();
		statement("float3x3 adj;	// The adjoint matrix (inverse after dividing by determinant)");
		statement_no_indent("");
		statement("// Create the transpose of the cofactors, as the classical adjoint of the matrix.");
		statement("adj[0][0] =  spvDet2x2(m[1][1], m[1][2], m[2][1], m[2][2]);");
		statement("adj[0][1] = -spvDet2x2(m[0][1], m[0][2], m[2][1], m[2][2]);");
		statement("adj[0][2] =  spvDet2x2(m[0][1], m[0][2], m[1][1], m[1][2]);");
		statement_no_indent("");
		statement("adj[1][0] = -spvDet2x2(m[1][0], m[1][2], m[2][0], m[2][2]);");
		statement("adj[1][1] =  spvDet2x2(m[0][0], m[0][2], m[2][0], m[2][2]);");
		statement("adj[1][2] = -spvDet2x2(m[0][0], m[0][2], m[1][0], m[1][2]);");
		statement_no_indent("");
		statement("adj[2][0] =  spvDet2x2(m[1][0], m[1][1], m[2][0], m[2][1]);");
		statement("adj[2][1] = -spvDet2x2(m[0][0], m[0][1], m[2][0], m[2][1]);");
		statement("adj[2][2] =  spvDet2x2(m[0][0], m[0][1], m[1][0], m[1][1]);");
		statement_no_indent("");
		statement("// Calculate the determinant as a combination of the cofactors of the first row.");
		statement("float det = (adj[0][0] * m[0][0]) + (adj[0][1] * m[1][0]) + (adj[0][2] * m[2][0]);");
		statement_no_indent("");
		statement("// Divide the classical adjoint matrix by the determinant.");
		statement("// If determinant is zero, matrix is not invertable, so leave it unchanged.");
		statement("return (det != 0.0f) ? (adj * (1.0f / det)) : m;");
		end_scope();
		statement("");
	}

	if (requires_inverse_4x4)
	{
		if (!requires_inverse_3x3)
		{
			statement("// Returns the determinant of a 2x2 matrix.");
			statement("float spvDet2x2(float a1, float a2, float b1, float b2)");
			begin_scope();
			statement("return a1 * b2 - b1 * a2;");
			end_scope();
			statement("");
		}

		statement("// Returns the determinant of a 3x3 matrix.");
		statement("float spvDet3x3(float a1, float a2, float a3, float b1, float b2, float b3, float c1, "
		          "float c2, float c3)");
		begin_scope();
		statement("return a1 * spvDet2x2(b2, b3, c2, c3) - b1 * spvDet2x2(a2, a3, c2, c3) + c1 * "
		          "spvDet2x2(a2, a3, "
		          "b2, b3);");
		end_scope();
		statement_no_indent("");
		statement("// Returns the inverse of a matrix, by using the algorithm of calculating the classical");
		statement("// adjoint and dividing by the determinant. The contents of the matrix are changed.");
		statement("float4x4 spvInverse(float4x4 m)");
		begin_scope();
		statement("float4x4 adj;	// The adjoint matrix (inverse after dividing by determinant)");
		statement_no_indent("");
		statement("// Create the transpose of the cofactors, as the classical adjoint of the matrix.");
		statement(
		    "adj[0][0] =  spvDet3x3(m[1][1], m[1][2], m[1][3], m[2][1], m[2][2], m[2][3], m[3][1], m[3][2], "
		    "m[3][3]);");
		statement(
		    "adj[0][1] = -spvDet3x3(m[0][1], m[0][2], m[0][3], m[2][1], m[2][2], m[2][3], m[3][1], m[3][2], "
		    "m[3][3]);");
		statement(
		    "adj[0][2] =  spvDet3x3(m[0][1], m[0][2], m[0][3], m[1][1], m[1][2], m[1][3], m[3][1], m[3][2], "
		    "m[3][3]);");
		statement(
		    "adj[0][3] = -spvDet3x3(m[0][1], m[0][2], m[0][3], m[1][1], m[1][2], m[1][3], m[2][1], m[2][2], "
		    "m[2][3]);");
		statement_no_indent("");
		statement(
		    "adj[1][0] = -spvDet3x3(m[1][0], m[1][2], m[1][3], m[2][0], m[2][2], m[2][3], m[3][0], m[3][2], "
		    "m[3][3]);");
		statement(
		    "adj[1][1] =  spvDet3x3(m[0][0], m[0][2], m[0][3], m[2][0], m[2][2], m[2][3], m[3][0], m[3][2], "
		    "m[3][3]);");
		statement(
		    "adj[1][2] = -spvDet3x3(m[0][0], m[0][2], m[0][3], m[1][0], m[1][2], m[1][3], m[3][0], m[3][2], "
		    "m[3][3]);");
		statement(
		    "adj[1][3] =  spvDet3x3(m[0][0], m[0][2], m[0][3], m[1][0], m[1][2], m[1][3], m[2][0], m[2][2], "
		    "m[2][3]);");
		statement_no_indent("");
		statement(
		    "adj[2][0] =  spvDet3x3(m[1][0], m[1][1], m[1][3], m[2][0], m[2][1], m[2][3], m[3][0], m[3][1], "
		    "m[3][3]);");
		statement(
		    "adj[2][1] = -spvDet3x3(m[0][0], m[0][1], m[0][3], m[2][0], m[2][1], m[2][3], m[3][0], m[3][1], "
		    "m[3][3]);");
		statement(
		    "adj[2][2] =  spvDet3x3(m[0][0], m[0][1], m[0][3], m[1][0], m[1][1], m[1][3], m[3][0], m[3][1], "
		    "m[3][3]);");
		statement(
		    "adj[2][3] = -spvDet3x3(m[0][0], m[0][1], m[0][3], m[1][0], m[1][1], m[1][3], m[2][0], m[2][1], "
		    "m[2][3]);");
		statement_no_indent("");
		statement(
		    "adj[3][0] = -spvDet3x3(m[1][0], m[1][1], m[1][2], m[2][0], m[2][1], m[2][2], m[3][0], m[3][1], "
		    "m[3][2]);");
		statement(
		    "adj[3][1] =  spvDet3x3(m[0][0], m[0][1], m[0][2], m[2][0], m[2][1], m[2][2], m[3][0], m[3][1], "
		    "m[3][2]);");
		statement(
		    "adj[3][2] = -spvDet3x3(m[0][0], m[0][1], m[0][2], m[1][0], m[1][1], m[1][2], m[3][0], m[3][1], "
		    "m[3][2]);");
		statement(
		    "adj[3][3] =  spvDet3x3(m[0][0], m[0][1], m[0][2], m[1][0], m[1][1], m[1][2], m[2][0], m[2][1], "
		    "m[2][2]);");
		statement_no_indent("");
		statement("// Calculate the determinant as a combination of the cofactors of the first row.");
		statement("float det = (adj[0][0] * m[0][0]) + (adj[0][1] * m[1][0]) + (adj[0][2] * m[2][0]) + (adj[0][3] "
		          "* m[3][0]);");
		statement_no_indent("");
		statement("// Divide the classical adjoint matrix by the determinant.");
		statement("// If determinant is zero, matrix is not invertable, so leave it unchanged.");
		statement("return (det != 0.0f) ? (adj * (1.0f / det)) : m;");
		end_scope();
		statement("");
	}

	if (requires_scalar_reflect)
	{
		// FP16/FP64? No templates in HLSL.
		statement("float spvReflect(float i, float n)");
		begin_scope();
		statement("return i - 2.0 * dot(n, i) * n;");
		end_scope();
		statement("");
	}

	if (requires_scalar_refract)
	{
		// FP16/FP64? No templates in HLSL.
		statement("float spvRefract(float i, float n, float eta)");
		begin_scope();
		statement("float NoI = n * i;");
		statement("float NoI2 = NoI * NoI;");
		statement("float k = 1.0 - eta * eta * (1.0 - NoI2);");
		statement("if (k < 0.0)");
		begin_scope();
		statement("return 0.0;");
		end_scope();
		statement("else");
		begin_scope();
		statement("return eta * i - (eta * NoI + sqrt(k)) * n;");
		end_scope();
		end_scope();
		statement("");
	}

	if (requires_scalar_faceforward)
	{
		// FP16/FP64? No templates in HLSL.
		statement("float spvFaceForward(float n, float i, float nref)");
		begin_scope();
		statement("return i * nref < 0.0 ? n : -n;");
		end_scope();
		statement("");
	}
#endif // SPIRV_CROSS_WEBMIN

	for (TypeID type_id : composite_selection_workaround_types)
	{
		// Need out variable since HLSL does not support returning arrays.
		auto &type = get<SPIRType>(type_id);
		auto type_str = type_to_glsl(type);
		auto type_arr_str = type_to_array_glsl(type);
		statement("void spvSelectComposite(out ", type_str, " out_value", type_arr_str, ", bool cond, ",
		          type_str, " true_val", type_arr_str, ", ",
		          type_str, " false_val", type_arr_str, ")");
		begin_scope();
		statement("if (cond)");
		begin_scope();
		statement("out_value = true_val;");
		end_scope();
		statement("else");
		begin_scope();
		statement("out_value = false_val;");
		end_scope();
		end_scope();
		statement("");
	}

#ifndef SPIRV_CROSS_WEBMIN
	if (is_mesh_shader && options.vertex.flip_vert_y)
	{
		statement("float4 spvFlipVertY(float4 v)");
		begin_scope();
		statement("return float4(v.x, -v.y, v.z, v.w);");
		end_scope();
		statement("");
		statement("float spvFlipVertY(float v)");
		begin_scope();
		statement("return -v;");
		end_scope();
		statement("");
	}
#endif
}

void CompilerHLSL::emit_texture_size_variants(uint64_t variant_mask, const char *vecsize_qualifier, bool uav,
                                              const char *type_qualifier)
{
	if (variant_mask == 0)
		return;

	static const char *types[QueryTypeCount] = { "float", "int", "uint" };
	static const char *dims[QueryDimCount] = { "Texture1D",   "Texture1DArray",  "Texture2D",   "Texture2DArray",
		                                       "Texture3D",   "Buffer",          "TextureCube", "TextureCubeArray",
		                                       "Texture2DMS", "Texture2DMSArray" };

	static const bool has_lod[QueryDimCount] = { true, true, true, true, true, false, true, true, false, false };

	static const char *ret_types[QueryDimCount] = {
		"uint", "uint2", "uint2", "uint3", "uint3", "uint", "uint2", "uint3", "uint2", "uint3",
	};

	static const uint32_t return_arguments[QueryDimCount] = {
		1, 2, 2, 3, 3, 1, 2, 3, 2, 3,
	};

	for (uint32_t index = 0; index < QueryDimCount; index++)
	{
		for (uint32_t type_index = 0; type_index < QueryTypeCount; type_index++)
		{
			uint32_t bit = 16 * type_index + index;
			uint64_t mask = 1ull << bit;

			if ((variant_mask & mask) == 0)
				continue;

			statement(ret_types[index], " spv", (uav ? "Image" : "Texture"), "Size(", (uav ? "RW" : ""),
			          dims[index], "<", type_qualifier, types[type_index], vecsize_qualifier, "> Tex, ",
			          (uav ? "" : "uint Level, "), "out uint Param)");
			begin_scope();
			statement(ret_types[index], " ret;");
			switch (return_arguments[index])
			{
			case 1:
				if (has_lod[index] && !uav)
					statement("Tex.GetDimensions(Level, ret.x, Param);");
				else
				{
					statement("Tex.GetDimensions(ret.x);");
					statement("Param = 0u;");
				}
				break;
			case 2:
				if (has_lod[index] && !uav)
					statement("Tex.GetDimensions(Level, ret.x, ret.y, Param);");
				else if (!uav)
					statement("Tex.GetDimensions(ret.x, ret.y, Param);");
				else
				{
					statement("Tex.GetDimensions(ret.x, ret.y);");
					statement("Param = 0u;");
				}
				break;
			case 3:
				if (has_lod[index] && !uav)
					statement("Tex.GetDimensions(Level, ret.x, ret.y, ret.z, Param);");
				else if (!uav)
					statement("Tex.GetDimensions(ret.x, ret.y, ret.z, Param);");
				else
				{
					statement("Tex.GetDimensions(ret.x, ret.y, ret.z);");
					statement("Param = 0u;");
				}
				break;
			}

			statement("return ret;");
			end_scope();
			statement("");
		}
	}
}

string CompilerHLSL::layout_for_member(const SPIRType &type, uint32_t index)
{
	auto &flags = get_member_decoration_bitset(type.self, index);

	// HLSL can emit row_major or column_major decoration in any struct.
	// Do not try to merge combined decorations for children like in GLSL.

	// Flip the convention. HLSL is a bit odd in that the memory layout is column major ... but the language API is "row-major".
	// The way to deal with this is to multiply everything in inverse order, and reverse the memory layout.
	if (flags.get(DecorationColMajor))
		return "row_major ";
	else if (flags.get(DecorationRowMajor))
		return "column_major ";

	return "";
}

void CompilerHLSL::emit_struct_member(const SPIRType &type, uint32_t member_type_id, uint32_t index,
                                      const string &qualifier, uint32_t base_offset)
{
	auto &membertype = get<SPIRType>(member_type_id);

	Bitset memberflags;
	auto &memb = ir.meta[type.self].members;
	if (index < memb.size())
		memberflags = memb[index].decoration_flags;

	string packing_offset;
	bool is_push_constant = type.storage == StorageClassPushConstant;

	if ((has_extended_decoration(type.self, SPIRVCrossDecorationExplicitOffset) || is_push_constant) &&
	    has_member_decoration(type.self, index, DecorationOffset))
	{
		uint32_t offset = memb[index].offset - base_offset;
		if (offset & 3)
			SPIRV_CROSS_THROW("Cannot pack on tighter bounds than 4 bytes in HLSL.");

		static const char *packing_swizzle[] = { "", ".y", ".z", ".w" };
		packing_offset = join(" : packoffset(c", offset / 16, packing_swizzle[(offset & 15) >> 2], ")");
	}

	statement(layout_for_member(type, index), qualifier,
	          variable_decl(membertype, to_member_name(type, index)), packing_offset, ";");
}

void CompilerHLSL::emit_buffer_block(const SPIRVariable &var)
{
	auto &type = get<SPIRType>(var.basetype);

	bool is_uav = var.storage == StorageClassStorageBuffer || has_decoration(type.self, DecorationBufferBlock);

	if (flattened_buffer_blocks.count(var.self))
	{
		emit_buffer_block_flattened(var);
	}
	else if (is_uav)
	{
		Bitset flags = ir.get_buffer_block_flags(var);
		bool is_readonly = flags.get(DecorationNonWritable) && !is_hlsl_force_storage_buffer_as_uav(var.self);
		bool is_coherent = flags.get(DecorationCoherent) && !is_readonly;
		bool is_interlocked = interlocked_resources.count(var.self) > 0;

		auto to_structuredbuffer_subtype_name = [this](const SPIRType &parent_type) -> std::string
		{
			if (parent_type.basetype == SPIRType::Struct && parent_type.member_types.size() == 1)
			{
				// Use type of first struct member as a StructuredBuffer will have only one '._m0' field in SPIR-V
				const auto &member0_type = this->get<SPIRType>(parent_type.member_types.front());
				return this->type_to_glsl(member0_type);
			}
			else
			{
				// Otherwise, this StructuredBuffer only has a basic subtype, e.g. StructuredBuffer<int>
				return this->type_to_glsl(parent_type);
			}
		};

		std::string type_name;
		if (is_user_type_structured(var.self))
			type_name = join(is_readonly ? "" : is_interlocked ? "RasterizerOrdered" : "RW", "StructuredBuffer<", to_structuredbuffer_subtype_name(type), ">");
		else
			type_name = is_readonly ? "ByteAddressBuffer" : is_interlocked ? "RasterizerOrderedByteAddressBuffer" : "RWByteAddressBuffer";

		add_resource_name(var.self);
		statement(is_coherent ? "globallycoherent " : "", type_name, " ", to_name(var.self), type_to_array_glsl(type),
		          to_resource_binding(var), ";");
	}
	else
	{
		if (type.array.empty())
		{
			// Flatten the top-level struct so we can use packoffset,
			// this restriction is similar to GLSL where layout(offset) is not possible on sub-structs.
			flattened_structs[var.self] = false;

			// Prefer the block name if possible.
			auto buffer_name = to_name(type.self, false);
			if (ir.meta[type.self].decoration.alias.empty() ||
			    resource_names.find(buffer_name) != end(resource_names) ||
			    block_names.find(buffer_name) != end(block_names))
			{
				buffer_name = get_block_fallback_name(var.self);
			}

			add_variable(block_names, resource_names, buffer_name);

			// If for some reason buffer_name is an illegal name, make a final fallback to a workaround name.
			// This cannot conflict with anything else, so we're safe now.
			if (buffer_name.empty())
				buffer_name = join("_", get<SPIRType>(var.basetype).self, "_", var.self);

			uint32_t failed_index = 0;
			if (buffer_is_packing_standard(type, BufferPackingHLSLCbufferPackOffset, &failed_index))
				set_extended_decoration(type.self, SPIRVCrossDecorationExplicitOffset);
			else
			{
				SPIRV_CROSS_THROW(join("cbuffer ID ", var.self, " (name: ", buffer_name, "), member index ",
				                       failed_index, " (name: ", to_member_name(type, failed_index),
				                       ") cannot be expressed with either HLSL packing layout or packoffset."));
			}

			block_names.insert(buffer_name);

			// Save for post-reflection later.
			declared_block_names[var.self] = buffer_name;

			type.member_name_cache.clear();
			// var.self can be used as a backup name for the block name,
			// so we need to make sure we don't disturb the name here on a recompile.
			// It will need to be reset if we have to recompile.
			preserve_alias_on_reset(var.self);
			add_resource_name(var.self);
			statement("cbuffer ", buffer_name, to_resource_binding(var));
			begin_scope();

			uint32_t i = 0;
			for (auto &member : type.member_types)
			{
				add_member_name(type, i);
				auto backup_name = get_member_name(type.self, i);
				auto member_name = to_member_name(type, i);
				member_name = join(to_name(var.self), "_", member_name);
				ParsedIR::sanitize_underscores(member_name);
				set_member_name(type.self, i, member_name);
				emit_struct_member(type, member, i, "");
				set_member_name(type.self, i, backup_name);
				i++;
			}

			end_scope_decl();
			statement("");
		}
		else
		{
			if (hlsl_options.shader_model < 51)
				SPIRV_CROSS_THROW(
				    "Need ConstantBuffer<T> to use arrays of UBOs, but this is only supported in SM 5.1.");

			add_resource_name(type.self);
			add_resource_name(var.self);

			// ConstantBuffer<T> does not support packoffset, so it is unuseable unless everything aligns as we expect.
			uint32_t failed_index = 0;
			if (!buffer_is_packing_standard(type, BufferPackingHLSLCbuffer, &failed_index))
			{
				SPIRV_CROSS_THROW(join("HLSL ConstantBuffer<T> ID ", var.self, " (name: ", to_name(type.self),
				                       "), member index ", failed_index, " (name: ", to_member_name(type, failed_index),
				                       ") cannot be expressed with normal HLSL packing rules."));
			}

			emit_struct(get<SPIRType>(type.self));
			statement("ConstantBuffer<", to_name(type.self), "> ", to_name(var.self), type_to_array_glsl(type),
			          to_resource_binding(var), ";");
		}
	}
}

string CompilerHLSL::to_sampler_expression(uint32_t id)
{
	auto expr = join("_", to_non_uniform_aware_expression(id));
	auto index = expr.find_first_of('[');
	if (index == string::npos)
	{
		return expr + "_sampler";
	}
	else
	{
		// We have an expression like _ident[array], so we cannot tack on _sampler, insert it inside the string instead.
		return expr.insert(index, "_sampler");
	}
}

void CompilerHLSL::emit_sampled_image_op(uint32_t result_type, uint32_t result_id, uint32_t image_id, uint32_t samp_id)
{
	if (hlsl_options.shader_model >= 40 && combined_image_samplers.empty())
	{
		set<SPIRCombinedImageSampler>(result_id, result_type, image_id, samp_id);
	}
	else
	{
		// Make sure to suppress usage tracking. It is illegal to create temporaries of opaque types.
		emit_op(result_type, result_id, to_combined_image_sampler(image_id, samp_id), true, true);
	}
}

string CompilerHLSL::to_func_call_arg(const SPIRFunction::Parameter &arg, uint32_t id)
{
	string arg_str = CompilerGLSL_to_func_call_arg(arg, id);

	if (hlsl_options.shader_model <= 30)
		return arg_str;

	// Manufacture automatic sampler arg if the arg is a SampledImage texture and we're in modern HLSL.
	auto &type = expression_type(id);

	// We don't have to consider combined image samplers here via OpSampledImage because
	// those variables cannot be passed as arguments to functions.
	// Only global SampledImage variables may be used as arguments.
	if (type.basetype == SPIRType::SampledImage && type.image.dim != DimBuffer)
		arg_str += ", " + to_sampler_expression(id);

	return arg_str;
}

string CompilerHLSL::get_inner_entry_point_name() const
{
	auto &execution = get_entry_point();

	if (hlsl_options.use_entry_point_name)
	{
		auto name = join(execution.name, "_inner");
		ParsedIR::sanitize_underscores(name);
		return name;
	}

	if (execution.model == ExecutionModelVertex)
		return "vert_main";
	else if (execution.model == ExecutionModelFragment)
		return "frag_main";
	else if (execution.model == ExecutionModelGLCompute)
		return "comp_main";
	else if (execution.model == ExecutionModelMeshEXT)
		return "mesh_main";
	else if (execution.model == ExecutionModelTaskEXT)
		return "task_main";
	else
		SPIRV_CROSS_THROW("Unsupported execution model.");
}

void CompilerHLSL::emit_function_prototype(SPIRFunction &func, const Bitset &return_flags)
{
	if (func.self != ir.default_entry_point)
		add_function_overload(func);

	// Avoid shadow declarations.
	local_variable_names = resource_names;

	string decl;

	auto &type = get<SPIRType>(func.return_type);
	if (type.array.empty())
	{
		decl += flags_to_qualifiers_glsl(type, return_flags);
		decl += type_to_glsl(type);
		decl += " ";
	}
	else
	{
		// We cannot return arrays in HLSL, so "return" through an out variable.
		decl = "void ";
	}

	if (func.self == ir.default_entry_point)
	{
		decl += get_inner_entry_point_name();
		processing_entry_point = true;
	}
	else
		decl += to_name(func.self);

	decl += "(";
	SmallVector<string> arglist;

	if (!type.array.empty())
	{
		// Fake array returns by writing to an out array instead.
		string out_argument;
		out_argument += "out ";
		out_argument += type_to_glsl(type);
		out_argument += " ";
		out_argument += "spvReturnValue";
		out_argument += type_to_array_glsl(type);
		arglist.push_back(std::move(out_argument));
	}

	for (auto &arg : func.arguments)
	{
		// Do not pass in separate images or samplers if we're remapping
		// to combined image samplers.
		if (skip_argument(arg.id))
			continue;

		// Might change the variable name if it already exists in this function.
		// SPIRV OpName doesn't have any semantic effect, so it's valid for an implementation
		// to use same name for variables.
		// Since we want to make the GLSL debuggable and somewhat sane, use fallback names for variables which are duplicates.
		add_local_variable_name(arg.id);

		arglist.push_back(argument_decl(arg));

		// Flatten a combined sampler to two separate arguments in modern HLSL.
		auto &arg_type = get<SPIRType>(arg.type);
		if (hlsl_options.shader_model > 30 && arg_type.basetype == SPIRType::SampledImage &&
		    arg_type.image.dim != DimBuffer)
		{
			// Manufacture automatic sampler arg for SampledImage texture
			arglist.push_back(join(is_depth_image(arg_type, arg.id) ? "SamplerComparisonState " : "SamplerState ",
			                       to_sampler_expression(arg.id), type_to_array_glsl(arg_type)));
		}

		// Hold a pointer to the parameter so we can invalidate the readonly field if needed.
		auto *var = maybe_get<SPIRVariable>(arg.id);
		if (var)
			var->parameter = &arg;
	}

	for (auto &arg : func.shadow_arguments)
	{
		// Might change the variable name if it already exists in this function.
		// SPIRV OpName doesn't have any semantic effect, so it's valid for an implementation
		// to use same name for variables.
		// Since we want to make the GLSL debuggable and somewhat sane, use fallback names for variables which are duplicates.
		add_local_variable_name(arg.id);

		arglist.push_back(argument_decl(arg));

		// Hold a pointer to the parameter so we can invalidate the readonly field if needed.
		auto *var = maybe_get<SPIRVariable>(arg.id);
		if (var)
			var->parameter = &arg;
	}

	decl += merge(arglist);
	decl += ")";
	statement(decl);
}

void CompilerHLSL::emit_hlsl_entry_point()
{
	SmallVector<string> arguments;

	if (require_input)
		arguments.push_back("SPIRV_Cross_Input stage_input");

	auto &execution = get_entry_point();

	switch (execution.model)
	{
	case ExecutionModelTaskEXT:
	case ExecutionModelMeshEXT:
	case ExecutionModelGLCompute:
	{
		if (execution.model == ExecutionModelMeshEXT)
		{
			if (execution.flags.get(ExecutionModeOutputTrianglesEXT))
				statement("[outputtopology(\"triangle\")]");
			else if (execution.flags.get(ExecutionModeOutputLinesEXT))
				statement("[outputtopology(\"line\")]");
			else if (execution.flags.get(ExecutionModeOutputPoints))
				SPIRV_CROSS_THROW("Topology mode \"points\" is not supported in DirectX");

			auto &func = get<SPIRFunction>(ir.default_entry_point);
			for (auto &arg : func.arguments)
			{
				auto &var = get<SPIRVariable>(arg.id);
				auto &base_type = get<SPIRType>(var.basetype);
				bool block = has_decoration(base_type.self, DecorationBlock);
				if (var.storage == StorageClassTaskPayloadWorkgroupEXT)
				{
					arguments.push_back("in payload " + variable_decl(var));
				}
				else if (block)
				{
					auto flags = get_buffer_block_flags(var.self);
					if (flags.get(DecorationPerPrimitiveEXT) || has_decoration(arg.id, DecorationPerPrimitiveEXT))
					{
						arguments.push_back("out primitives gl_MeshPerPrimitiveEXT gl_MeshPrimitivesEXT[" +
						                    std::to_string(execution.output_primitives) + "]");
					}
					else
					{
						arguments.push_back("out vertices gl_MeshPerVertexEXT gl_MeshVerticesEXT[" +
						                    std::to_string(execution.output_vertices) + "]");
					}
				}
				else
				{
					if (execution.flags.get(ExecutionModeOutputTrianglesEXT))
					{
						arguments.push_back("out indices uint3 gl_PrimitiveTriangleIndicesEXT[" +
						                    std::to_string(execution.output_primitives) + "]");
					}
					else
					{
						arguments.push_back("out indices uint2 gl_PrimitiveLineIndicesEXT[" +
						                    std::to_string(execution.output_primitives) + "]");
					}
				}
			}
		}
		SpecializationConstant wg_x, wg_y, wg_z;
		get_work_group_size_specialization_constants(wg_x, wg_y, wg_z);

		uint32_t x = execution.workgroup_size.x;
		uint32_t y = execution.workgroup_size.y;
		uint32_t z = execution.workgroup_size.z;

		if (!execution.workgroup_size.constant && execution.flags.get(ExecutionModeLocalSizeId))
		{
			if (execution.workgroup_size.id_x)
				x = get<SPIRConstant>(execution.workgroup_size.id_x).scalar();
			if (execution.workgroup_size.id_y)
				y = get<SPIRConstant>(execution.workgroup_size.id_y).scalar();
			if (execution.workgroup_size.id_z)
				z = get<SPIRConstant>(execution.workgroup_size.id_z).scalar();
		}

		auto x_expr = wg_x.id ? get<SPIRConstant>(wg_x.id).specialization_constant_macro_name : to_string(x);
		auto y_expr = wg_y.id ? get<SPIRConstant>(wg_y.id).specialization_constant_macro_name : to_string(y);
		auto z_expr = wg_z.id ? get<SPIRConstant>(wg_z.id).specialization_constant_macro_name : to_string(z);

		statement("[numthreads(", x_expr, ", ", y_expr, ", ", z_expr, ")]");
		break;
	}
	case ExecutionModelFragment:
		if (execution.flags.get(ExecutionModeEarlyFragmentTests))
			statement("[earlydepthstencil]");
		break;
	default:
		break;
	}

	const char *entry_point_name;
	if (hlsl_options.use_entry_point_name)
		entry_point_name = get_entry_point().name.c_str();
	else
		entry_point_name = "main";

	statement(require_output ? "SPIRV_Cross_Output " : "void ", entry_point_name, "(", merge(arguments), ")");
	begin_scope();
	bool legacy = hlsl_options.shader_model <= 30;

	// Copy builtins from entry point arguments to globals.
	active_input_builtins.for_each_bit([&](uint32_t i) {
		auto builtin = builtin_to_glsl(static_cast<BuiltIn>(i), StorageClassInput);
		switch (static_cast<BuiltIn>(i))
		{
		case BuiltInFragCoord:
			// VPOS in D3D9 is sampled at integer locations, apply half-pixel offset to be consistent.
			// TODO: Do we need an option here? Any reason why a D3D9 shader would be used
			// on a D3D10+ system with a different rasterization config?
			if (legacy)
				statement(builtin, " = stage_input.", builtin, " + float4(0.5f, 0.5f, 0.0f, 0.0f);");
			else
			{
				statement(builtin, " = stage_input.", builtin, ";");
				// ZW are undefined in D3D9, only do this fixup here.
				statement(builtin, ".w = 1.0 / ", builtin, ".w;");
			}
			break;

		case BuiltInVertexId:
		case BuiltInVertexIndex:
		case BuiltInInstanceIndex:
			// D3D semantics are uint, but shader wants int.
			if (hlsl_options.support_nonzero_base_vertex_base_instance)
			{
				if (static_cast<BuiltIn>(i) == BuiltInInstanceIndex)
					statement(builtin, " = int(stage_input.", builtin, ") + SPIRV_Cross_BaseInstance;");
				else
					statement(builtin, " = int(stage_input.", builtin, ") + SPIRV_Cross_BaseVertex;");
			}
			else
				statement(builtin, " = int(stage_input.", builtin, ");");
			break;

		case BuiltInBaseVertex:
			statement(builtin, " = SPIRV_Cross_BaseVertex;");
			break;

		case BuiltInBaseInstance:
			statement(builtin, " = SPIRV_Cross_BaseInstance;");
			break;

		case BuiltInInstanceId:
			// D3D semantics are uint, but shader wants int.
			statement(builtin, " = int(stage_input.", builtin, ");");
			break;

		case BuiltInNumWorkgroups:
		case BuiltInPointCoord:
		case BuiltInSubgroupSize:
		case BuiltInSubgroupLocalInvocationId:
		case BuiltInHelperInvocation:
			break;

		case BuiltInSubgroupEqMask:
#ifndef SPIRV_CROSS_WEBMIN
			// Emulate these ...
			// No 64-bit in HLSL, so have to do it in 32-bit and unroll.
			statement("gl_SubgroupEqMask = 1u << (WaveGetLaneIndex() - uint4(0, 32, 64, 96));");
			statement("if (WaveGetLaneIndex() >= 32) gl_SubgroupEqMask.x = 0;");
			statement("if (WaveGetLaneIndex() >= 64 || WaveGetLaneIndex() < 32) gl_SubgroupEqMask.y = 0;");
			statement("if (WaveGetLaneIndex() >= 96 || WaveGetLaneIndex() < 64) gl_SubgroupEqMask.z = 0;");
			statement("if (WaveGetLaneIndex() < 96) gl_SubgroupEqMask.w = 0;");
#endif
			break;

		case BuiltInSubgroupGeMask:
#ifndef SPIRV_CROSS_WEBMIN
			// Emulate these ...
			// No 64-bit in HLSL, so have to do it in 32-bit and unroll.
			statement("gl_SubgroupGeMask = ~((1u << (WaveGetLaneIndex() - uint4(0, 32, 64, 96))) - 1u);");
			statement("if (WaveGetLaneIndex() >= 32) gl_SubgroupGeMask.x = 0u;");
			statement("if (WaveGetLaneIndex() >= 64) gl_SubgroupGeMask.y = 0u;");
			statement("if (WaveGetLaneIndex() >= 96) gl_SubgroupGeMask.z = 0u;");
			statement("if (WaveGetLaneIndex() < 32) gl_SubgroupGeMask.y = ~0u;");
			statement("if (WaveGetLaneIndex() < 64) gl_SubgroupGeMask.z = ~0u;");
			statement("if (WaveGetLaneIndex() < 96) gl_SubgroupGeMask.w = ~0u;");
#endif
			break;

		case BuiltInSubgroupGtMask:
#ifndef SPIRV_CROSS_WEBMIN
			// Emulate these ...
			// No 64-bit in HLSL, so have to do it in 32-bit and unroll.
			statement("uint gt_lane_index = WaveGetLaneIndex() + 1;");
			statement("gl_SubgroupGtMask = ~((1u << (gt_lane_index - uint4(0, 32, 64, 96))) - 1u);");
			statement("if (gt_lane_index >= 32) gl_SubgroupGtMask.x = 0u;");
			statement("if (gt_lane_index >= 64) gl_SubgroupGtMask.y = 0u;");
			statement("if (gt_lane_index >= 96) gl_SubgroupGtMask.z = 0u;");
			statement("if (gt_lane_index >= 128) gl_SubgroupGtMask.w = 0u;");
			statement("if (gt_lane_index < 32) gl_SubgroupGtMask.y = ~0u;");
			statement("if (gt_lane_index < 64) gl_SubgroupGtMask.z = ~0u;");
			statement("if (gt_lane_index < 96) gl_SubgroupGtMask.w = ~0u;");
#endif
			break;

		case BuiltInSubgroupLeMask:
#ifndef SPIRV_CROSS_WEBMIN
			// Emulate these ...
			// No 64-bit in HLSL, so have to do it in 32-bit and unroll.
			statement("uint le_lane_index = WaveGetLaneIndex() + 1;");
			statement("gl_SubgroupLeMask = (1u << (le_lane_index - uint4(0, 32, 64, 96))) - 1u;");
			statement("if (le_lane_index >= 32) gl_SubgroupLeMask.x = ~0u;");
			statement("if (le_lane_index >= 64) gl_SubgroupLeMask.y = ~0u;");
			statement("if (le_lane_index >= 96) gl_SubgroupLeMask.z = ~0u;");
			statement("if (le_lane_index >= 128) gl_SubgroupLeMask.w = ~0u;");
			statement("if (le_lane_index < 32) gl_SubgroupLeMask.y = 0u;");
			statement("if (le_lane_index < 64) gl_SubgroupLeMask.z = 0u;");
			statement("if (le_lane_index < 96) gl_SubgroupLeMask.w = 0u;");
#endif
			break;

		case BuiltInSubgroupLtMask:
#ifndef SPIRV_CROSS_WEBMIN
			// Emulate these ...
			// No 64-bit in HLSL, so have to do it in 32-bit and unroll.
			statement("gl_SubgroupLtMask = (1u << (WaveGetLaneIndex() - uint4(0, 32, 64, 96))) - 1u;");
			statement("if (WaveGetLaneIndex() >= 32) gl_SubgroupLtMask.x = ~0u;");
			statement("if (WaveGetLaneIndex() >= 64) gl_SubgroupLtMask.y = ~0u;");
			statement("if (WaveGetLaneIndex() >= 96) gl_SubgroupLtMask.z = ~0u;");
			statement("if (WaveGetLaneIndex() < 32) gl_SubgroupLtMask.y = 0u;");
			statement("if (WaveGetLaneIndex() < 64) gl_SubgroupLtMask.z = 0u;");
			statement("if (WaveGetLaneIndex() < 96) gl_SubgroupLtMask.w = 0u;");
#endif
			break;

		case BuiltInClipDistance:
#ifndef SPIRV_CROSS_WEBMIN
			for (uint32_t clip = 0; clip < clip_distance_count; clip++)
				statement("gl_ClipDistance[", clip, "] = stage_input.gl_ClipDistance", clip / 4, ".", "xyzw"[clip & 3],
				          ";");
#endif
			break;

		case BuiltInCullDistance:
#ifndef SPIRV_CROSS_WEBMIN
			for (uint32_t cull = 0; cull < cull_distance_count; cull++)
				statement("gl_CullDistance[", cull, "] = stage_input.gl_CullDistance", cull / 4, ".", "xyzw"[cull & 3],
				          ";");
#endif
			break;

		default:
			statement(builtin, " = stage_input.", builtin, ";");
			break;
		}
	});

	// Copy from stage input struct to globals.
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);
		bool block = has_decoration(type.self, DecorationBlock);

		if (var.storage != StorageClassInput)
			return;

		bool need_matrix_unroll = var.storage == StorageClassInput && execution.model == ExecutionModelVertex;

		if (!var.remapped_variable && type.pointer && !is_builtin_variable(var) &&
		    interface_variable_exists_in_entry_point(var.self))
		{
			if (block)
			{
				auto type_name = to_name(type.self);
				auto var_name = to_name(var.self);
				for (uint32_t mbr_idx = 0; mbr_idx < uint32_t(type.member_types.size()); mbr_idx++)
				{
					auto mbr_name = to_member_name(type, mbr_idx);
					auto flat_name = join(type_name, "_", mbr_name);
					statement(var_name, ".", mbr_name, " = stage_input.", flat_name, ";");
				}
			}
			else
			{
				auto name = to_name(var.self);
				auto &mtype = this->get<SPIRType>(var.basetype);
				if (need_matrix_unroll && mtype.columns > 1)
				{
					// Unroll matrices.
					for (uint32_t col = 0; col < mtype.columns; col++)
						statement(name, "[", col, "] = stage_input.", name, "_", col, ";");
				}
				else
				{
					statement(name, " = stage_input.", name, ";");
				}
			}
		}
	});

	// Run the shader.
	if (execution.model == ExecutionModelVertex ||
	    execution.model == ExecutionModelFragment ||
	    execution.model == ExecutionModelGLCompute ||
	    execution.model == ExecutionModelMeshEXT ||
	    execution.model == ExecutionModelTaskEXT)
	{
		// For mesh shaders, we receive special arguments that we must pass down as function arguments.
		// HLSL does not support proper reference types for passing these IO blocks,
		// but DXC post-inlining seems to magically fix it up anyways *shrug*.
		SmallVector<string> arglist;
		auto &func = get<SPIRFunction>(ir.default_entry_point);
		// The arguments are marked out, avoid detecting reads and emitting inout.
		for (auto &arg : func.arguments)
			arglist.push_back(to_expression(arg.id, false));
		statement(get_inner_entry_point_name(), "(", merge(arglist), ");");
	}
	else
		SPIRV_CROSS_THROW("Unsupported shader stage.");

	// Copy stage outputs.
	if (require_output)
	{
		statement("SPIRV_Cross_Output stage_output;");

		// Copy builtins from globals to return struct.
		active_output_builtins.for_each_bit([&](uint32_t i) {
			// PointSize doesn't exist in HLSL SM 4+.
			if (i == BuiltInPointSize && !legacy)
				return;

			switch (static_cast<BuiltIn>(i))
			{
			case BuiltInClipDistance:
				for (uint32_t clip = 0; clip < clip_distance_count; clip++)
					statement("stage_output.gl_ClipDistance", clip / 4, ".", "xyzw"[clip & 3], " = gl_ClipDistance[",
					          clip, "];");
				break;

			case BuiltInCullDistance:
				for (uint32_t cull = 0; cull < cull_distance_count; cull++)
					statement("stage_output.gl_CullDistance", cull / 4, ".", "xyzw"[cull & 3], " = gl_CullDistance[",
					          cull, "];");
				break;

			default:
			{
				auto builtin_expr = builtin_to_glsl(static_cast<BuiltIn>(i), StorageClassOutput);
				statement("stage_output.", builtin_expr, " = ", builtin_expr, ";");
				break;
			}
			}
		});

		ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
			auto &type = this->get<SPIRType>(var.basetype);
			bool block = has_decoration(type.self, DecorationBlock);

			if (var.storage != StorageClassOutput)
				return;

			if (!var.remapped_variable && type.pointer &&
			    !is_builtin_variable(var) &&
			    interface_variable_exists_in_entry_point(var.self))
			{
				if (block)
				{
					// I/O blocks need to flatten output.
					auto type_name = to_name(type.self);
					auto var_name = to_name(var.self);
					for (uint32_t mbr_idx = 0; mbr_idx < uint32_t(type.member_types.size()); mbr_idx++)
					{
						auto mbr_name = to_member_name(type, mbr_idx);
						auto flat_name = join(type_name, "_", mbr_name);
						statement("stage_output.", flat_name, " = ", var_name, ".", mbr_name, ";");
					}
				}
				else
				{
					auto name = to_name(var.self);

					if (legacy && execution.model == ExecutionModelFragment)
					{
						string output_filler;
						for (uint32_t size = type.vecsize; size < 4; ++size)
							output_filler += ", 0.0";

						statement("stage_output.", name, " = float4(", name, output_filler, ");");
					}
					else
					{
						statement("stage_output.", name, " = ", name, ";");
					}
				}
			}
		});

		statement("return stage_output;");
	}

	end_scope();
}

void CompilerHLSL::emit_fixup()
{
	if (is_vertex_like_shader() && active_output_builtins.get(BuiltInPosition))
	{
		// Do various mangling on the gl_Position.
		if (hlsl_options.shader_model <= 30)
		{
			statement("gl_Position.x = gl_Position.x - gl_HalfPixel.x * "
			          "gl_Position.w;");
			statement("gl_Position.y = gl_Position.y + gl_HalfPixel.y * "
			          "gl_Position.w;");
		}

		if (options.vertex.flip_vert_y)
			statement("gl_Position.y = -gl_Position.y;");
		if (options.vertex.fixup_clipspace)
			statement("gl_Position.z = (gl_Position.z + gl_Position.w) * 0.5;");
	}
}

void CompilerHLSL::emit_texture_op(const Instruction &i, bool sparse)
{
	if (sparse)
		SPIRV_CROSS_THROW("Sparse feedback not yet supported in HLSL.");

	auto *ops = stream(i);
	auto op = static_cast<Op>(i.op);
	uint32_t length = i.length;

	SmallVector<uint32_t> inherited_expressions;

	uint32_t result_type = ops[0];
	uint32_t id = ops[1];
	VariableID img = ops[2];
	uint32_t coord = ops[3];
	uint32_t dref = 0;
	uint32_t comp = 0;
	bool gather = false;
	bool proj = false;
	const uint32_t *opt = nullptr;
	auto *combined_image = maybe_get<SPIRCombinedImageSampler>(img);

	if (combined_image && has_decoration(img, DecorationNonUniform))
	{
		set_decoration(combined_image->image, DecorationNonUniform);
		set_decoration(combined_image->sampler, DecorationNonUniform);
	}

	auto img_expr = to_non_uniform_aware_expression(combined_image ? combined_image->image : img);

	inherited_expressions.push_back(coord);

	switch (op)
	{
	case OpImageSampleDrefImplicitLod:
	case OpImageSampleDrefExplicitLod:
		dref = ops[4];
		opt = &ops[5];
		length -= 5;
		break;

	case OpImageSampleProjDrefImplicitLod:
	case OpImageSampleProjDrefExplicitLod:
		dref = ops[4];
		proj = true;
		opt = &ops[5];
		length -= 5;
		break;

	case OpImageDrefGather:
		dref = ops[4];
		opt = &ops[5];
		gather = true;
		length -= 5;
		break;

	case OpImageGather:
		comp = ops[4];
		opt = &ops[5];
		gather = true;
		length -= 5;
		break;

	case OpImageSampleProjImplicitLod:
	case OpImageSampleProjExplicitLod:
		opt = &ops[4];
		length -= 4;
		proj = true;
		break;

	case OpImageQueryLod:
		opt = &ops[4];
		length -= 4;
		break;

	default:
		opt = &ops[4];
		length -= 4;
		break;
	}

	auto &imgtype = expression_type(img);
	uint32_t coord_components = 0;
	switch (imgtype.image.dim)
	{
	case spv::Dim1D:
		coord_components = 1;
		break;
	case spv::Dim2D:
		coord_components = 2;
		break;
	case spv::Dim3D:
		coord_components = 3;
		break;
	case spv::DimCube:
		coord_components = 3;
		break;
	case spv::DimBuffer:
		coord_components = 1;
		break;
	default:
		coord_components = 2;
		break;
	}

	if (dref)
		inherited_expressions.push_back(dref);

	if (imgtype.image.arrayed)
		coord_components++;

	uint32_t bias = 0;
	uint32_t lod = 0;
	uint32_t grad_x = 0;
	uint32_t grad_y = 0;
	uint32_t coffset = 0;
	uint32_t offset = 0;
	uint32_t coffsets = 0;
	uint32_t sample = 0;
	uint32_t minlod = 0;
	uint32_t flags = 0;

	if (length)
	{
		flags = opt[0];
		opt++;
		length--;
	}

	auto test = [&](uint32_t &v, uint32_t flag) {
		if (length && (flags & flag))
		{
			v = *opt++;
			inherited_expressions.push_back(v);
			length--;
		}
	};

	test(bias, ImageOperandsBiasMask);
	test(lod, ImageOperandsLodMask);
	test(grad_x, ImageOperandsGradMask);
	test(grad_y, ImageOperandsGradMask);
	test(coffset, ImageOperandsConstOffsetMask);
	test(offset, ImageOperandsOffsetMask);
	test(coffsets, ImageOperandsConstOffsetsMask);
	test(sample, ImageOperandsSampleMask);
	test(minlod, ImageOperandsMinLodMask);

	string expr;
	string texop;

	if (minlod != 0)
		SPIRV_CROSS_THROW("MinLod texture operand not supported in HLSL.");

	if (op == OpImageFetch)
	{
		if (hlsl_options.shader_model < 40)
		{
			SPIRV_CROSS_THROW("texelFetch is not supported in HLSL shader model 2/3.");
		}
		texop += img_expr;
		texop += ".Load";
	}
	else if (op == OpImageQueryLod)
	{
		texop += img_expr;
		texop += ".CalculateLevelOfDetail";
	}
	else
	{
		auto &imgformat = get<SPIRType>(imgtype.image.type);
		if (hlsl_options.shader_model < 67 && imgformat.basetype != SPIRType::Float)
		{
			SPIRV_CROSS_THROW("Sampling non-float textures is not supported in HLSL SM < 6.7.");
		}

		if (hlsl_options.shader_model >= 40)
		{
			texop += img_expr;

			if (is_depth_image(imgtype, img))
			{
				if (gather)
				{
					texop += ".GatherCmp";
				}
				else if (lod || grad_x || grad_y)
				{
					// Assume we want a fixed level, and the only thing we can get in HLSL is SampleCmpLevelZero.
					texop += ".SampleCmpLevelZero";
				}
				else
					texop += ".SampleCmp";
			}
			else if (gather)
			{
				uint32_t comp_num = evaluate_constant_u32(comp);
				if (hlsl_options.shader_model >= 50)
				{
					switch (comp_num)
					{
					case 0:
						texop += ".GatherRed";
						break;
					case 1:
						texop += ".GatherGreen";
						break;
					case 2:
						texop += ".GatherBlue";
						break;
					case 3:
						texop += ".GatherAlpha";
						break;
					default:
						SPIRV_CROSS_THROW("Invalid component.");
					}
				}
				else
				{
					if (comp_num == 0)
						texop += ".Gather";
					else
						SPIRV_CROSS_THROW("HLSL shader model 4 can only gather from the red component.");
				}
			}
			else if (bias)
				texop += ".SampleBias";
			else if (grad_x || grad_y)
				texop += ".SampleGrad";
			else if (lod)
				texop += ".SampleLevel";
			else
				texop += ".Sample";
		}
		else
		{
			switch (imgtype.image.dim)
			{
			case Dim1D:
				texop += "tex1D";
				break;
			case Dim2D:
				texop += "tex2D";
				break;
			case Dim3D:
				texop += "tex3D";
				break;
			case DimCube:
				texop += "texCUBE";
				break;
			case DimRect:
			case DimBuffer:
			case DimSubpassData:
				SPIRV_CROSS_THROW("Buffer texture support is not yet implemented for HLSL"); // TODO
			default:
				SPIRV_CROSS_THROW("Invalid dimension.");
			}

			if (gather)
				SPIRV_CROSS_THROW("textureGather is not supported in HLSL shader model 2/3.");
			if (offset || coffset)
				SPIRV_CROSS_THROW("textureOffset is not supported in HLSL shader model 2/3.");

			if (grad_x || grad_y)
				texop += "grad";
			else if (lod)
				texop += "lod";
			else if (bias)
				texop += "bias";
			else if (proj || dref)
				texop += "proj";
		}
	}

	expr += texop;
	expr += "(";
	if (hlsl_options.shader_model < 40)
	{
		if (combined_image)
			SPIRV_CROSS_THROW("Separate images/samplers are not supported in HLSL shader model 2/3.");
		expr += to_expression(img);
	}
	else if (op != OpImageFetch)
	{
		string sampler_expr;
		if (combined_image)
			sampler_expr = to_non_uniform_aware_expression(combined_image->sampler);
		else
			sampler_expr = to_sampler_expression(img);
		expr += sampler_expr;
	}

	auto swizzle = [](uint32_t comps, uint32_t in_comps) -> const char * {
		if (comps == in_comps)
			return "";

		switch (comps)
		{
		case 1:
			return ".x";
		case 2:
			return ".xy";
		case 3:
			return ".xyz";
		default:
			return "";
		}
	};

	bool forward = should_forward(coord);

	// The IR can give us more components than we need, so chop them off as needed.
	string coord_expr;
	auto &coord_type = expression_type(coord);
	if (coord_components != coord_type.vecsize)
		coord_expr = to_enclosed_expression(coord) + swizzle(coord_components, expression_type(coord).vecsize);
	else
		coord_expr = to_expression(coord);

	if (proj && hlsl_options.shader_model >= 40) // Legacy HLSL has "proj" operations which do this for us.
		coord_expr = coord_expr + " / " + to_extract_component_expression(coord, coord_components);

	if (hlsl_options.shader_model < 40)
	{
		if (dref)
		{
			if (imgtype.image.dim != spv::Dim1D && imgtype.image.dim != spv::Dim2D)
			{
				SPIRV_CROSS_THROW(
				    "Depth comparison is only supported for 1D and 2D textures in HLSL shader model 2/3.");
			}

			if (grad_x || grad_y)
				SPIRV_CROSS_THROW("Depth comparison is not supported for grad sampling in HLSL shader model 2/3.");

			for (uint32_t size = coord_components; size < 2; ++size)
				coord_expr += ", 0.0";

			forward = forward && should_forward(dref);
			coord_expr += ", " + to_expression(dref);
		}
		else if (lod || bias || proj)
		{
			for (uint32_t size = coord_components; size < 3; ++size)
				coord_expr += ", 0.0";
		}

		if (lod)
		{
			coord_expr = "float4(" + coord_expr + ", " + to_expression(lod) + ")";
		}
		else if (bias)
		{
			coord_expr = "float4(" + coord_expr + ", " + to_expression(bias) + ")";
		}
		else if (proj)
		{
			coord_expr = "float4(" + coord_expr + ", " + to_extract_component_expression(coord, coord_components) + ")";
		}
		else if (dref)
		{
			// A "normal" sample gets fed into tex2Dproj as well, because the
			// regular tex2D accepts only two coordinates.
			coord_expr = "float4(" + coord_expr + ", 1.0)";
		}

		if (!!lod + !!bias + !!proj > 1)
			SPIRV_CROSS_THROW("Legacy HLSL can only use one of lod/bias/proj modifiers.");
	}

	if (op == OpImageFetch)
	{
		if (imgtype.image.dim != DimBuffer && !imgtype.image.ms)
			coord_expr =
			    join("int", coord_components + 1, "(", coord_expr, ", ", lod ? to_expression(lod) : string("0"), ")");
	}
	else
		expr += ", ";
	expr += coord_expr;

	if (dref && hlsl_options.shader_model >= 40)
	{
		forward = forward && should_forward(dref);
		expr += ", ";

		if (proj)
			expr += to_enclosed_expression(dref) + " / " + to_extract_component_expression(coord, coord_components);
		else
			expr += to_expression(dref);
	}

	if (!dref && (grad_x || grad_y))
	{
		forward = forward && should_forward(grad_x);
		forward = forward && should_forward(grad_y);
		expr += ", ";
		expr += to_expression(grad_x);
		expr += ", ";
		expr += to_expression(grad_y);
	}

	if (!dref && lod && hlsl_options.shader_model >= 40 && op != OpImageFetch)
	{
		forward = forward && should_forward(lod);
		expr += ", ";
		expr += to_expression(lod);
	}

	if (!dref && bias && hlsl_options.shader_model >= 40)
	{
		forward = forward && should_forward(bias);
		expr += ", ";
		expr += to_expression(bias);
	}

	if (coffset)
	{
		forward = forward && should_forward(coffset);
		expr += ", ";
		expr += to_expression(coffset);
	}
	else if (offset)
	{
		forward = forward && should_forward(offset);
		expr += ", ";
		expr += to_expression(offset);
	}

	if (sample)
	{
		expr += ", ";
		expr += to_expression(sample);
	}

	expr += ")";

	if (dref && hlsl_options.shader_model < 40)
		expr += ".x";

	if (op == OpImageQueryLod)
	{
		// This is rather awkward.
		// textureQueryLod returns two values, the "accessed level",
		// as well as the actual LOD lambda.
		// As far as I can tell, there is no way to get the .x component
		// according to GLSL spec, and it depends on the sampler itself.
		// Just assume X == Y, so we will need to splat the result to a float2.
		statement("float _", id, "_tmp = ", expr, ";");
		statement("float2 _", id, " = _", id, "_tmp.xx;");
		set<SPIRExpression>(id, join("_", id), result_type, true);
	}
	else
	{
		emit_op(result_type, id, expr, forward, false);
	}

	for (auto &inherit : inherited_expressions)
		inherit_expression_dependencies(id, inherit);

	switch (op)
	{
	case OpImageSampleDrefImplicitLod:
	case OpImageSampleImplicitLod:
	case OpImageSampleProjImplicitLod:
	case OpImageSampleProjDrefImplicitLod:
		register_control_dependent_expression(id);
		break;

	default:
		break;
	}
}

string CompilerHLSL::to_resource_binding(const SPIRVariable &var)
{
	const auto &type = get<SPIRType>(var.basetype);

	// We can remap push constant blocks, even if they don't have any binding decoration.
	if (type.storage != StorageClassPushConstant && !has_decoration(var.self, DecorationBinding))
		return "";

	char space = '\0';

	HLSLBindingFlagBits resource_flags = HLSL_BINDING_AUTO_NONE_BIT;

	switch (type.basetype)
	{
	case SPIRType::SampledImage:
		space = 't'; // SRV
		resource_flags = HLSL_BINDING_AUTO_SRV_BIT;
		break;

	case SPIRType::Image:
		if (type.image.sampled == 2 && type.image.dim != DimSubpassData)
		{
			if (has_decoration(var.self, DecorationNonWritable) && hlsl_options.nonwritable_uav_texture_as_srv)
			{
				space = 't'; // SRV
				resource_flags = HLSL_BINDING_AUTO_SRV_BIT;
			}
			else
			{
				space = 'u'; // UAV
				resource_flags = HLSL_BINDING_AUTO_UAV_BIT;
			}
		}
		else
		{
			space = 't'; // SRV
			resource_flags = HLSL_BINDING_AUTO_SRV_BIT;
		}
		break;

	case SPIRType::Sampler:
		space = 's';
		resource_flags = HLSL_BINDING_AUTO_SAMPLER_BIT;
		break;

	case SPIRType::AccelerationStructure:
		space = 't'; // SRV
		resource_flags = HLSL_BINDING_AUTO_SRV_BIT;
		break;

	case SPIRType::Struct:
	{
		auto storage = type.storage;
		if (storage == StorageClassUniform)
		{
			if (has_decoration(type.self, DecorationBufferBlock))
			{
				Bitset flags = ir.get_buffer_block_flags(var);
				bool is_readonly = flags.get(DecorationNonWritable) && !is_hlsl_force_storage_buffer_as_uav(var.self);
				space = is_readonly ? 't' : 'u'; // UAV
				resource_flags = is_readonly ? HLSL_BINDING_AUTO_SRV_BIT : HLSL_BINDING_AUTO_UAV_BIT;
			}
			else if (has_decoration(type.self, DecorationBlock))
			{
				space = 'b'; // Constant buffers
				resource_flags = HLSL_BINDING_AUTO_CBV_BIT;
			}
		}
		else if (storage == StorageClassPushConstant)
		{
			space = 'b'; // Constant buffers
			resource_flags = HLSL_BINDING_AUTO_PUSH_CONSTANT_BIT;
		}
		else if (storage == StorageClassStorageBuffer)
		{
			// UAV or SRV depending on readonly flag.
			Bitset flags = ir.get_buffer_block_flags(var);
			bool is_readonly = flags.get(DecorationNonWritable) && !is_hlsl_force_storage_buffer_as_uav(var.self);
			space = is_readonly ? 't' : 'u';
			resource_flags = is_readonly ? HLSL_BINDING_AUTO_SRV_BIT : HLSL_BINDING_AUTO_UAV_BIT;
		}

		break;
	}
	default:
		break;
	}

	if (!space)
		return "";

	uint32_t desc_set =
	    resource_flags == HLSL_BINDING_AUTO_PUSH_CONSTANT_BIT ? ResourceBindingPushConstantDescriptorSet : 0u;
	uint32_t binding = resource_flags == HLSL_BINDING_AUTO_PUSH_CONSTANT_BIT ? ResourceBindingPushConstantBinding : 0u;

	if (has_decoration(var.self, DecorationBinding))
		binding = get_decoration(var.self, DecorationBinding);
	if (has_decoration(var.self, DecorationDescriptorSet))
		desc_set = get_decoration(var.self, DecorationDescriptorSet);

	return to_resource_register(resource_flags, space, binding, desc_set);
}

string CompilerHLSL::to_resource_binding_sampler(const SPIRVariable &var)
{
	// For combined image samplers.
	if (!has_decoration(var.self, DecorationBinding))
		return "";

	return to_resource_register(HLSL_BINDING_AUTO_SAMPLER_BIT, 's', get_decoration(var.self, DecorationBinding),
	                            get_decoration(var.self, DecorationDescriptorSet));
}

void CompilerHLSL::remap_hlsl_resource_binding(HLSLBindingFlagBits type, uint32_t &desc_set, uint32_t &binding)
{
	auto itr = resource_bindings.find({ get_execution_model(), desc_set, binding });
	if (itr != end(resource_bindings))
	{
		auto &remap = itr->second;
		remap.second = true;

		switch (type)
		{
		case HLSL_BINDING_AUTO_PUSH_CONSTANT_BIT:
		case HLSL_BINDING_AUTO_CBV_BIT:
			desc_set = remap.first.cbv.register_space;
			binding = remap.first.cbv.register_binding;
			break;

		case HLSL_BINDING_AUTO_SRV_BIT:
			desc_set = remap.first.srv.register_space;
			binding = remap.first.srv.register_binding;
			break;

		case HLSL_BINDING_AUTO_SAMPLER_BIT:
			desc_set = remap.first.sampler.register_space;
			binding = remap.first.sampler.register_binding;
			break;

		case HLSL_BINDING_AUTO_UAV_BIT:
			desc_set = remap.first.uav.register_space;
			binding = remap.first.uav.register_binding;
			break;

		default:
			break;
		}
	}
}

string CompilerHLSL::to_resource_register(HLSLBindingFlagBits flag, char space, uint32_t binding, uint32_t space_set)
{
	if ((flag & resource_binding_flags) == 0)
	{
		remap_hlsl_resource_binding(flag, space_set, binding);

		// The push constant block did not have a binding, and there were no remap for it,
		// so, declare without register binding.
		if (flag == HLSL_BINDING_AUTO_PUSH_CONSTANT_BIT && space_set == ResourceBindingPushConstantDescriptorSet)
			return "";

		if (hlsl_options.shader_model >= 51)
			return join(" : register(", space, binding, ", space", space_set, ")");
		else
			return join(" : register(", space, binding, ")");
	}
	else
		return "";
}

void CompilerHLSL::emit_modern_uniform(const SPIRVariable &var)
{
	auto &type = get<SPIRType>(var.basetype);
	switch (type.basetype)
	{
	case SPIRType::SampledImage:
	case SPIRType::Image:
	{
		bool is_coherent = false;
		if (type.basetype == SPIRType::Image && type.image.sampled == 2)
			is_coherent = has_decoration(var.self, DecorationCoherent);

		statement(is_coherent ? "globallycoherent " : "", image_type_hlsl_modern(type, var.self), " ",
		          to_name(var.self), type_to_array_glsl(type), to_resource_binding(var), ";");

		if (type.basetype == SPIRType::SampledImage && type.image.dim != DimBuffer)
		{
			// For combined image samplers, also emit a combined image sampler.
			if (is_depth_image(type, var.self))
				statement("SamplerComparisonState ", to_sampler_expression(var.self), type_to_array_glsl(type),
				          to_resource_binding_sampler(var), ";");
			else
				statement("SamplerState ", to_sampler_expression(var.self), type_to_array_glsl(type),
				          to_resource_binding_sampler(var), ";");
		}
		break;
	}

	case SPIRType::Sampler:
		if (comparison_ids.count(var.self))
			statement("SamplerComparisonState ", to_name(var.self), type_to_array_glsl(type), to_resource_binding(var),
			          ";");
		else
			statement("SamplerState ", to_name(var.self), type_to_array_glsl(type), to_resource_binding(var), ";");
		break;

	default:
		statement(variable_decl(var), to_resource_binding(var), ";");
		break;
	}
}

void CompilerHLSL::emit_uniform(const SPIRVariable &var)
{
	add_resource_name(var.self);
	if (hlsl_options.shader_model >= 40)
		emit_modern_uniform(var);
	else
		emit_legacy_uniform(var);
}

bool CompilerHLSL::emit_complex_bitcast(uint32_t, uint32_t, uint32_t)
{
	return false;
}

void CompilerHLSL::emit_glsl_op(uint32_t result_type, uint32_t id, uint32_t eop, const uint32_t *args, uint32_t count)
{
	auto op = static_cast<GLSLstd450>(eop);

	// If we need to do implicit bitcasts, make sure we do it with the correct type.
	uint32_t integer_width = get_integer_width_for_glsl_instruction(op, args, count);
	auto int_type = to_signed_basetype(integer_width);
	auto uint_type = to_unsigned_basetype(integer_width);

	op = get_remapped_glsl_op(op);

	switch (op)
	{
	case GLSLstd450InverseSqrt:
		emit_unary_func_op(result_type, id, args[0], "rsqrt");
		break;

	case GLSLstd450Fract:
		emit_unary_func_op(result_type, id, args[0], "frac");
		break;

	case GLSLstd450RoundEven:
		if (hlsl_options.shader_model < 40)
			SPIRV_CROSS_THROW("roundEven is not supported in HLSL shader model 2/3.");
		emit_unary_func_op(result_type, id, args[0], "round");
		break;

	case GLSLstd450Trunc:
		emit_unary_func_op(result_type, id, args[0], "trunc");
		break;

	case GLSLstd450Acosh:
	case GLSLstd450Asinh:
	case GLSLstd450Atanh:
		// These are not supported in HLSL, always emulate them.
		emit_emulated_ahyper_op(result_type, id, args[0], op);
		break;

	case GLSLstd450FMix:
	case GLSLstd450IMix:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "lerp");
		break;

	case GLSLstd450Atan2:
		emit_binary_func_op(result_type, id, args[0], args[1], "atan2");
		break;

	case GLSLstd450Fma:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "mad");
		break;

	case GLSLstd450InterpolateAtCentroid:
		emit_unary_func_op(result_type, id, args[0], "EvaluateAttributeAtCentroid");
		break;
	case GLSLstd450InterpolateAtSample:
		emit_binary_func_op(result_type, id, args[0], args[1], "EvaluateAttributeAtSample");
		break;
	case GLSLstd450InterpolateAtOffset:
		emit_binary_func_op(result_type, id, args[0], args[1], "EvaluateAttributeSnapped");
		break;

	case GLSLstd450PackHalf2x16:
		if (!requires_fp16_packing)
		{
			requires_fp16_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvPackHalf2x16");
		break;

	case GLSLstd450UnpackHalf2x16:
		if (!requires_fp16_packing)
		{
			requires_fp16_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvUnpackHalf2x16");
		break;

	case GLSLstd450PackSnorm4x8:
		if (!requires_snorm8_packing)
		{
			requires_snorm8_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvPackSnorm4x8");
		break;

	case GLSLstd450UnpackSnorm4x8:
		if (!requires_snorm8_packing)
		{
			requires_snorm8_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvUnpackSnorm4x8");
		break;

	case GLSLstd450PackUnorm4x8:
		if (!requires_unorm8_packing)
		{
			requires_unorm8_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvPackUnorm4x8");
		break;

	case GLSLstd450UnpackUnorm4x8:
		if (!requires_unorm8_packing)
		{
			requires_unorm8_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvUnpackUnorm4x8");
		break;

	case GLSLstd450PackSnorm2x16:
		if (!requires_snorm16_packing)
		{
			requires_snorm16_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvPackSnorm2x16");
		break;

	case GLSLstd450UnpackSnorm2x16:
		if (!requires_snorm16_packing)
		{
			requires_snorm16_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvUnpackSnorm2x16");
		break;

	case GLSLstd450PackUnorm2x16:
		if (!requires_unorm16_packing)
		{
			requires_unorm16_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvPackUnorm2x16");
		break;

	case GLSLstd450UnpackUnorm2x16:
		if (!requires_unorm16_packing)
		{
			requires_unorm16_packing = true;
			force_recompile();
		}
		emit_unary_func_op(result_type, id, args[0], "spvUnpackUnorm2x16");
		break;

	case GLSLstd450PackDouble2x32:
	case GLSLstd450UnpackDouble2x32:
		SPIRV_CROSS_THROW("packDouble2x32/unpackDouble2x32 not supported in HLSL.");

	case GLSLstd450FindILsb:
	{
		auto basetype = expression_type(args[0]).basetype;
		emit_unary_func_op_cast(result_type, id, args[0], "firstbitlow", basetype, basetype);
		break;
	}

	case GLSLstd450FindSMsb:
		emit_unary_func_op_cast(result_type, id, args[0], "firstbithigh", int_type, int_type);
		break;

	case GLSLstd450FindUMsb:
		emit_unary_func_op_cast(result_type, id, args[0], "firstbithigh", uint_type, uint_type);
		break;

	case GLSLstd450MatrixInverse:
	{
		auto &type = get<SPIRType>(result_type);
		if (type.vecsize == 2 && type.columns == 2)
		{
			if (!requires_inverse_2x2)
			{
				requires_inverse_2x2 = true;
				force_recompile();
			}
		}
		else if (type.vecsize == 3 && type.columns == 3)
		{
			if (!requires_inverse_3x3)
			{
				requires_inverse_3x3 = true;
				force_recompile();
			}
		}
		else if (type.vecsize == 4 && type.columns == 4)
		{
			if (!requires_inverse_4x4)
			{
				requires_inverse_4x4 = true;
				force_recompile();
			}
		}
		emit_unary_func_op(result_type, id, args[0], "spvInverse");
		break;
	}

	case GLSLstd450Normalize:
		// HLSL does not support scalar versions here.
		if (expression_type(args[0]).vecsize == 1)
		{
			// Returns -1 or 1 for valid input, sign() does the job.
			emit_unary_func_op(result_type, id, args[0], "sign");
		}
		else
			CompilerGLSL_emit_glsl_op(result_type, id, eop, args, count);
		break;

	case GLSLstd450Reflect:
		if (get<SPIRType>(result_type).vecsize == 1)
		{
			if (!requires_scalar_reflect)
			{
				requires_scalar_reflect = true;
				force_recompile();
			}
			emit_binary_func_op(result_type, id, args[0], args[1], "spvReflect");
		}
		else
			CompilerGLSL_emit_glsl_op(result_type, id, eop, args, count);
		break;

	case GLSLstd450Refract:
		if (get<SPIRType>(result_type).vecsize == 1)
		{
			if (!requires_scalar_refract)
			{
				requires_scalar_refract = true;
				force_recompile();
			}
			emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "spvRefract");
		}
		else
			CompilerGLSL_emit_glsl_op(result_type, id, eop, args, count);
		break;

	case GLSLstd450FaceForward:
		if (get<SPIRType>(result_type).vecsize == 1)
		{
			if (!requires_scalar_faceforward)
			{
				requires_scalar_faceforward = true;
				force_recompile();
			}
			emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "spvFaceForward");
		}
		else
			CompilerGLSL_emit_glsl_op(result_type, id, eop, args, count);
		break;

	default:
		CompilerGLSL_emit_glsl_op(result_type, id, eop, args, count);
		break;
	}
}

void CompilerHLSL::emit_load(const Instruction &instruction)
{
	auto ops = stream(instruction);

	auto *chain = maybe_get<SPIRAccessChain>(ops[2]);
	if (chain)
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t ptr = ops[2];

		auto &type = get<SPIRType>(result_type);
		bool composite_load = !type.array.empty() || type.basetype == SPIRType::Struct;

		if (composite_load)
		{
			// We cannot make this work in one single expression as we might have nested structures and arrays,
			// so unroll the load to an uninitialized temporary.
			emit_uninitialized_temporary_expression(result_type, id);
			read_access_chain(nullptr, to_expression(id), *chain);
			track_expression_read(chain->self);
		}
		else
		{
			string load_expr;
			read_access_chain(&load_expr, "", *chain);

			bool forward = should_forward(ptr) && forced_temporaries.find(id) == end(forced_temporaries);

			// If we are forwarding this load,
			// don't register the read to access chain here, defer that to when we actually use the expression,
			// using the add_implied_read_expression mechanism.
			if (!forward)
				track_expression_read(chain->self);

			// Do not forward complex load sequences like matrices, structs and arrays.
			if (type.columns > 1)
				forward = false;

			auto &e = emit_op(result_type, id, load_expr, forward, true);
			e.need_transpose = false;
			register_read(id, ptr, forward);
			inherit_expression_dependencies(id, ptr);
			if (forward)
				add_implied_read_expression(e, chain->self);
		}
	}
	else
		CompilerGLSL_emit_instruction(instruction);
}

void CompilerHLSL::emit_store(const Instruction &instruction)
{
	auto ops = stream(instruction);
	if (options.vertex.flip_vert_y)
	{
		auto *expr = maybe_get<SPIRExpression>(ops[0]);
		if (expr != nullptr && expr->access_meshlet_position_y)
		{
			auto lhs = to_dereferenced_expression(ops[0]);
			auto rhs = to_unpacked_expression(ops[1]);
			statement(lhs, " = spvFlipVertY(", rhs, ");");
			register_write(ops[0]);
			return;
		}
	}

	auto *chain = maybe_get<SPIRAccessChain>(ops[0]);
	if (chain)
		write_access_chain(*chain, ops[1], {});
	else
		CompilerGLSL_emit_instruction(instruction);
}

void CompilerHLSL::emit_access_chain(const Instruction &instruction)
{
	auto ops = stream(instruction);
	uint32_t length = instruction.length;

	bool need_byte_access_chain = false;
	auto &type = expression_type(ops[2]);
	const auto *chain = maybe_get<SPIRAccessChain>(ops[2]);

	if (chain)
	{
		// Keep tacking on an existing access chain.
		need_byte_access_chain = true;
	}
	else if (type.storage == StorageClassStorageBuffer || has_decoration(type.self, DecorationBufferBlock))
	{
		// If we are starting to poke into an SSBO, we are dealing with ByteAddressBuffers, and we need
		// to emit SPIRAccessChain rather than a plain SPIRExpression.
		uint32_t chain_arguments = length - 3;
		if (chain_arguments > type.array.size())
			need_byte_access_chain = true;
	}

	if (need_byte_access_chain)
	{
		// If we have a chain variable, we are already inside the SSBO, and any array type will refer to arrays within a block,
		// and not array of SSBO.
		uint32_t to_plain_buffer_length = chain ? 0u : static_cast<uint32_t>(type.array.size());

		auto *backing_variable = maybe_get_backing_variable(ops[2]);

		if (backing_variable != nullptr && is_user_type_structured(backing_variable->self))
		{
			CompilerGLSL_emit_instruction(instruction);
			return;
		}

		string base;
		if (to_plain_buffer_length != 0)
			base = access_chain(ops[2], &ops[3], to_plain_buffer_length, get<SPIRType>(ops[0]));
		else if (chain)
			base = chain->base;
		else
			base = to_expression(ops[2]);

		// Start traversing type hierarchy at the proper non-pointer types.
		auto *basetype = &get_pointee_type(type);

		// Traverse the type hierarchy down to the actual buffer types.
		for (uint32_t i = 0; i < to_plain_buffer_length; i++)
		{
			assert(basetype->parent_type);
			basetype = &get<SPIRType>(basetype->parent_type);
		}

		uint32_t matrix_stride = 0;
		uint32_t array_stride = 0;
		bool row_major_matrix = false;

		// Inherit matrix information.
		if (chain)
		{
			matrix_stride = chain->matrix_stride;
			row_major_matrix = chain->row_major_matrix;
			array_stride = chain->array_stride;
		}

		auto offsets = flattened_access_chain_offset(*basetype, &ops[3 + to_plain_buffer_length],
		                                             length - 3 - to_plain_buffer_length, 0, 1, &row_major_matrix,
		                                             &matrix_stride, &array_stride);

		auto &e = set<SPIRAccessChain>(ops[1], ops[0], type.storage, base, offsets.first, offsets.second);
		e.row_major_matrix = row_major_matrix;
		e.matrix_stride = matrix_stride;
		e.array_stride = array_stride;
		e.immutable = should_forward(ops[2]);
		e.loaded_from = backing_variable ? backing_variable->self : ID(0);

		if (chain)
		{
			e.dynamic_index += chain->dynamic_index;
			e.static_index += chain->static_index;
		}

		for (uint32_t i = 2; i < length; i++)
		{
			inherit_expression_dependencies(ops[1], ops[i]);
			add_implied_read_expression(e, ops[i]);
		}
	}
	else
	{
		CompilerGLSL_emit_instruction(instruction);
	}
}

void CompilerHLSL::emit_instruction(const Instruction &instruction)
{
	auto ops = stream(instruction);
	auto opcode = static_cast<Op>(instruction.op);

#define HLSL_BOP(op) emit_binary_op(ops[0], ops[1], ops[2], ops[3], #op)
#define HLSL_BOP_CAST(op, type) \
	emit_binary_op_cast(ops[0], ops[1], ops[2], ops[3], #op, type, opcode_is_sign_invariant(opcode), false)
#define HLSL_UOP(op) emit_unary_op(ops[0], ops[1], ops[2], #op)
#define HLSL_QFOP(op) emit_quaternary_func_op(ops[0], ops[1], ops[2], ops[3], ops[4], ops[5], #op)
#define HLSL_TFOP(op) emit_trinary_func_op(ops[0], ops[1], ops[2], ops[3], ops[4], #op)
#define HLSL_BFOP(op) emit_binary_func_op(ops[0], ops[1], ops[2], ops[3], #op)
#define HLSL_BFOP_CAST(op, type) \
	emit_binary_func_op_cast(ops[0], ops[1], ops[2], ops[3], #op, type, opcode_is_sign_invariant(opcode))
#define HLSL_BFOP(op) emit_binary_func_op(ops[0], ops[1], ops[2], ops[3], #op)
#define HLSL_UFOP(op) emit_unary_func_op(ops[0], ops[1], ops[2], #op)

	// If we need to do implicit bitcasts, make sure we do it with the correct type.
	uint32_t integer_width = get_integer_width_for_instruction(instruction);
	auto int_type = to_signed_basetype(integer_width);
	auto uint_type = to_unsigned_basetype(integer_width);

	opcode = get_remapped_spirv_op(opcode);

	switch (opcode)
	{
	case OpAccessChain:
	case OpInBoundsAccessChain:
	{
		emit_access_chain(instruction);
		break;
	}
	case OpBitcast:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto bitcast_type = get_bitcast_type(ops[0], ops[2]);
		if (bitcast_type == CompilerHLSL::TypeNormal)
			CompilerGLSL_emit_instruction(instruction);
		else
		{
			if (!requires_uint2_packing)
			{
				requires_uint2_packing = true;
				force_recompile();
			}

			if (bitcast_type == CompilerHLSL::TypePackUint2x32)
				emit_unary_func_op(ops[0], ops[1], ops[2], "spvPackUint2x32");
			else
				emit_unary_func_op(ops[0], ops[1], ops[2], "spvUnpackUint2x32");
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSelect:
	{
		auto &value_type = expression_type(ops[3]);
		if (value_type.basetype == SPIRType::Struct || is_array(value_type))
		{
			// HLSL does not support ternary expressions on composites.
			// Cannot use branches, since we might be in a continue block
			// where explicit control flow is prohibited.
			// Emit a helper function where we can use control flow.
			TypeID value_type_id = expression_type_id(ops[3]);
			auto itr = std::find(composite_selection_workaround_types.begin(),
			                     composite_selection_workaround_types.end(),
			                     value_type_id);
			if (itr == composite_selection_workaround_types.end())
			{
				composite_selection_workaround_types.push_back(value_type_id);
				force_recompile();
			}
			emit_uninitialized_temporary_expression(ops[0], ops[1]);
			statement("spvSelectComposite(",
					  to_expression(ops[1]), ", ", to_expression(ops[2]), ", ",
					  to_expression(ops[3]), ", ", to_expression(ops[4]), ");");
		}
		else
			CompilerGLSL_emit_instruction(instruction);
		break;
	}

	case OpStore:
	{
		emit_store(instruction);
		break;
	}

	case OpLoad:
	{
		emit_load(instruction);
		break;
	}

	case OpMatrixTimesVector:
	{
		// Matrices are kept in a transposed state all the time, flip multiplication order always.
		emit_binary_func_op(ops[0], ops[1], ops[3], ops[2], "mul");
		break;
	}

	case OpVectorTimesMatrix:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// Matrices are kept in a transposed state all the time, flip multiplication order always.
		emit_binary_func_op(ops[0], ops[1], ops[3], ops[2], "mul");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpMatrixTimesMatrix:
	{
		// Matrices are kept in a transposed state all the time, flip multiplication order always.
		emit_binary_func_op(ops[0], ops[1], ops[3], ops[2], "mul");
		break;
	}

	case OpOuterProduct:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t a = ops[2];
		uint32_t b = ops[3];

		auto &type = get<SPIRType>(result_type);
		string expr = type_to_glsl_constructor(type);
		expr += "(";
		for (uint32_t col = 0; col < type.columns; col++)
		{
			expr += to_enclosed_expression(a);
			expr += " * ";
			expr += to_extract_component_expression(b, col);
			if (col + 1 < type.columns)
				expr += ", ";
		}
		expr += ")";
		emit_op(result_type, id, expr, should_forward(a) && should_forward(b));
		inherit_expression_dependencies(id, a);
		inherit_expression_dependencies(id, b);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFMod:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (!requires_op_fmod)
		{
			requires_op_fmod = true;
			force_recompile();
		}
		CompilerGLSL_emit_instruction(instruction);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFRem:
#ifndef SPIRV_CROSS_WEBMIN
		emit_binary_func_op(ops[0], ops[1], ops[2], ops[3], "fmod");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpImage:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		auto *combined = maybe_get<SPIRCombinedImageSampler>(ops[2]);

		if (combined)
		{
			auto &e = emit_op(result_type, id, to_expression(combined->image), true, true);
			auto *var = maybe_get_backing_variable(combined->image);
			if (var)
				e.loaded_from = var->self;
		}
		else
		{
			auto &e = emit_op(result_type, id, to_expression(ops[2]), true, true);
			auto *var = maybe_get_backing_variable(ops[2]);
			if (var)
				e.loaded_from = var->self;
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpDPdx:
		HLSL_UFOP(ddx);
		register_control_dependent_expression(ops[1]);
		break;

	case OpDPdy:
		HLSL_UFOP(ddy);
		register_control_dependent_expression(ops[1]);
		break;

	case OpDPdxFine:
#ifndef SPIRV_CROSS_WEBMIN
		HLSL_UFOP(ddx_fine);
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdyFine:
#ifndef SPIRV_CROSS_WEBMIN
		HLSL_UFOP(ddy_fine);
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdxCoarse:
#ifndef SPIRV_CROSS_WEBMIN
		HLSL_UFOP(ddx_coarse);
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdyCoarse:
#ifndef SPIRV_CROSS_WEBMIN
		HLSL_UFOP(ddy_coarse);
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpFwidth:
	case OpFwidthCoarse:
	case OpFwidthFine:
#ifndef SPIRV_CROSS_WEBMIN
		HLSL_UFOP(fwidth);
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpLogicalNot:
	{
		auto result_type = ops[0];
		auto id = ops[1];
		auto &type = get<SPIRType>(result_type);

		if (type.vecsize > 1)
			emit_unrolled_unary_op(result_type, id, ops[2], "!");
		else
			HLSL_UOP(!);
		break;
	}

	case OpIEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "==", false, SPIRType::Unknown);
		else
			HLSL_BOP_CAST(==, int_type);

		break;
	}

	case OpLogicalEqual:
	case OpFOrdEqual:
	case OpFUnordEqual:
	{
		// HLSL != operator is unordered.
		// https://docs.microsoft.com/en-us/windows/win32/direct3d10/d3d10-graphics-programming-guide-resources-float-rules.
		// isnan() is apparently implemented as x != x as well.
		// We cannot implement UnordEqual as !(OrdNotEqual), as HLSL cannot express OrdNotEqual.
		// HACK: FUnordEqual will be implemented as FOrdEqual.

		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "==", false, SPIRType::Unknown);
		else
			HLSL_BOP(==);
		break;
	}

	case OpINotEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "!=", false, SPIRType::Unknown);
		else
			HLSL_BOP_CAST(!=, int_type);

		break;
	}

	case OpLogicalNotEqual:
	case OpFOrdNotEqual:
	case OpFUnordNotEqual:
	{
		// HLSL != operator is unordered.
		// https://docs.microsoft.com/en-us/windows/win32/direct3d10/d3d10-graphics-programming-guide-resources-float-rules.
		// isnan() is apparently implemented as x != x as well.

		// FIXME: FOrdNotEqual cannot be implemented in a crisp and simple way here.
		// We would need to do something like not(UnordEqual), but that cannot be expressed either.
		// Adding a lot of NaN checks would be a breaking change from perspective of performance.
		// SPIR-V will generally use isnan() checks when this even matters.
		// HACK: FOrdNotEqual will be implemented as FUnordEqual.

		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "!=", false, SPIRType::Unknown);
		else
			HLSL_BOP(!=);

		break;
	}

	case OpUGreaterThan:
	case OpSGreaterThan:
	{
		auto result_type = ops[0];
		auto id = ops[1];
		auto type = opcode == OpUGreaterThan ? uint_type : int_type;

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], ">", false, type);
		else
			HLSL_BOP_CAST(>, type);

		break;
	}

	case OpFOrdGreaterThan:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], ">", false, SPIRType::Unknown);
		else
			HLSL_BOP(>);
		break;
	}

	case OpFUnordGreaterThan:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "<=", true, SPIRType::Unknown);
		else
			CompilerGLSL_emit_instruction(instruction);

		break;
	}

	case OpUGreaterThanEqual:
	case OpSGreaterThanEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		auto type = opcode == OpUGreaterThanEqual ? uint_type : int_type;
		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], ">=", false, type);
		else
			HLSL_BOP_CAST(>=, type);

		break;
	}

	case OpFOrdGreaterThanEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], ">=", false, SPIRType::Unknown);
		else
			HLSL_BOP(>=);
		break;
	}

	case OpFUnordGreaterThanEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "<", true, SPIRType::Unknown);
		else
			CompilerGLSL_emit_instruction(instruction);

		break;
	}

	case OpULessThan:
	case OpSLessThan:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		auto type = opcode == OpULessThan ? uint_type : int_type;
		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "<", false, type);
		else
			HLSL_BOP_CAST(<, type);

		break;
	}

	case OpFOrdLessThan:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "<", false, SPIRType::Unknown);
		else
			HLSL_BOP(<);
		break;
	}

	case OpFUnordLessThan:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], ">=", true, SPIRType::Unknown);
		else
			CompilerGLSL_emit_instruction(instruction);

		break;
	}

	case OpULessThanEqual:
	case OpSLessThanEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		auto type = opcode == OpULessThanEqual ? uint_type : int_type;
		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "<=", false, type);
		else
			HLSL_BOP_CAST(<=, type);
		break;
	}

	case OpFOrdLessThanEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "<=", false, SPIRType::Unknown);
		else
			HLSL_BOP(<=);
		break;
	}

	case OpFUnordLessThanEqual:
	{
		auto result_type = ops[0];
		auto id = ops[1];

		if (expression_type(ops[2]).vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], ">", true, SPIRType::Unknown);
		else
			CompilerGLSL_emit_instruction(instruction);

		break;
	}

	case OpImageQueryLod:
#ifndef SPIRV_CROSS_WEBMIN
		emit_texture_op(instruction, false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpImageQuerySizeLod:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto result_type = ops[0];
		auto id = ops[1];

		require_texture_query_variant(ops[2]);
		auto dummy_samples_levels = join(get_fallback_name(id), "_dummy_parameter");
		statement("uint ", dummy_samples_levels, ";");

		auto expr = join("spvTextureSize(", to_non_uniform_aware_expression(ops[2]), ", ",
		                 bitcast_expression(SPIRType::UInt, ops[3]), ", ", dummy_samples_levels, ")");

		auto &restype = get<SPIRType>(ops[0]);
		expr = bitcast_expression(restype, SPIRType::UInt, expr);
		emit_op(result_type, id, expr, true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageQuerySize:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto result_type = ops[0];
		auto id = ops[1];

		require_texture_query_variant(ops[2]);
		bool uav = expression_type(ops[2]).image.sampled == 2;

		if (const auto *var = maybe_get_backing_variable(ops[2]))
			if (hlsl_options.nonwritable_uav_texture_as_srv && has_decoration(var->self, DecorationNonWritable))
				uav = false;

		auto dummy_samples_levels = join(get_fallback_name(id), "_dummy_parameter");
		statement("uint ", dummy_samples_levels, ";");

		string expr;
		if (uav)
			expr = join("spvImageSize(", to_non_uniform_aware_expression(ops[2]), ", ", dummy_samples_levels, ")");
		else
			expr = join("spvTextureSize(", to_non_uniform_aware_expression(ops[2]), ", 0u, ", dummy_samples_levels, ")");

		auto &restype = get<SPIRType>(ops[0]);
		expr = bitcast_expression(restype, SPIRType::UInt, expr);
		emit_op(result_type, id, expr, true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageQuerySamples:
	case OpImageQueryLevels:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto result_type = ops[0];
		auto id = ops[1];

		require_texture_query_variant(ops[2]);
		bool uav = expression_type(ops[2]).image.sampled == 2;
		if (opcode == OpImageQueryLevels && uav)
			SPIRV_CROSS_THROW("Cannot query levels for UAV images.");

		if (const auto *var = maybe_get_backing_variable(ops[2]))
			if (hlsl_options.nonwritable_uav_texture_as_srv && has_decoration(var->self, DecorationNonWritable))
				uav = false;

		// Keep it simple and do not emit special variants to make this look nicer ...
		// This stuff is barely, if ever, used.
		forced_temporaries.insert(id);
		auto &type = get<SPIRType>(result_type);
		statement(variable_decl(type, to_name(id)), ";");

		if (uav)
			statement("spvImageSize(", to_non_uniform_aware_expression(ops[2]), ", ", to_name(id), ");");
		else
			statement("spvTextureSize(", to_non_uniform_aware_expression(ops[2]), ", 0u, ", to_name(id), ");");

		auto &restype = get<SPIRType>(ops[0]);
		auto expr = bitcast_expression(restype, SPIRType::UInt, to_name(id));
		set<SPIRExpression>(id, expr, result_type, true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageRead:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		auto *var = maybe_get_backing_variable(ops[2]);
		auto &type = expression_type(ops[2]);
		bool subpass_data = type.image.dim == DimSubpassData;
		bool pure = false;

		string imgexpr;

		if (subpass_data)
		{
			if (hlsl_options.shader_model < 40)
				SPIRV_CROSS_THROW("Subpass loads are not supported in HLSL shader model 2/3.");

			// Similar to GLSL, implement subpass loads using texelFetch.
			if (type.image.ms)
			{
				uint32_t operands = ops[4];
				if (operands != ImageOperandsSampleMask || instruction.length != 6)
					SPIRV_CROSS_THROW("Multisampled image used in OpImageRead, but unexpected operand mask was used.");
				uint32_t sample = ops[5];
				imgexpr = join(to_non_uniform_aware_expression(ops[2]), ".Load(int2(gl_FragCoord.xy), ", to_expression(sample), ")");
			}
			else
				imgexpr = join(to_non_uniform_aware_expression(ops[2]), ".Load(int3(int2(gl_FragCoord.xy), 0))");

			pure = true;
		}
		else
		{
			imgexpr = join(to_non_uniform_aware_expression(ops[2]), "[", to_expression(ops[3]), "]");
			// The underlying image type in HLSL depends on the image format, unlike GLSL, where all images are "vec4",
			// except that the underlying type changes how the data is interpreted.

			bool force_srv =
			    hlsl_options.nonwritable_uav_texture_as_srv && var && has_decoration(var->self, DecorationNonWritable);
			pure = force_srv;

			if (var && !subpass_data && !force_srv)
				imgexpr = remap_swizzle(get<SPIRType>(result_type),
				                        image_format_to_components(get<SPIRType>(var->basetype).image.format), imgexpr);
		}

		if (var)
		{
			bool forward = forced_temporaries.find(id) == end(forced_temporaries);
			auto &e = emit_op(result_type, id, imgexpr, forward);

			if (!pure)
			{
				e.loaded_from = var->self;
				if (forward)
					var->dependees.push_back(id);
			}
		}
		else
			emit_op(result_type, id, imgexpr, false);

		inherit_expression_dependencies(id, ops[2]);
		if (type.image.ms)
			inherit_expression_dependencies(id, ops[5]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageWrite:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto *var = maybe_get_backing_variable(ops[0]);

		// The underlying image type in HLSL depends on the image format, unlike GLSL, where all images are "vec4",
		// except that the underlying type changes how the data is interpreted.
		auto value_expr = to_expression(ops[2]);
		if (var)
		{
			auto &type = get<SPIRType>(var->basetype);
			auto narrowed_type = get<SPIRType>(type.image.type);
			narrowed_type.vecsize = image_format_to_components(type.image.format);
			value_expr = remap_swizzle(narrowed_type, expression_type(ops[2]).vecsize, value_expr);
		}

		statement(to_non_uniform_aware_expression(ops[0]), "[", to_expression(ops[1]), "] = ", value_expr, ";");
		if (var && variable_storage_is_aliased(*var))
			flush_all_aliased_variables();
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageTexelPointer:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		auto expr = to_expression(ops[2]);
		expr += join("[", to_expression(ops[3]), "]");
		auto &e = set<SPIRExpression>(id, expr, result_type, true);

		// When using the pointer, we need to know which variable it is actually loaded from.
		auto *var = maybe_get_backing_variable(ops[2]);
		e.loaded_from = var ? var->self : ID(0);
		inherit_expression_dependencies(id, ops[3]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicFAddEXT:
	case OpAtomicFMinEXT:
	case OpAtomicFMaxEXT:
		SPIRV_CROSS_THROW("Floating-point atomics are not supported in HLSL.");

	case OpAtomicCompareExchange:
	case OpAtomicExchange:
	case OpAtomicISub:
	case OpAtomicSMin:
	case OpAtomicUMin:
	case OpAtomicSMax:
	case OpAtomicUMax:
	case OpAtomicAnd:
	case OpAtomicOr:
	case OpAtomicXor:
	case OpAtomicIAdd:
	case OpAtomicIIncrement:
	case OpAtomicIDecrement:
	case OpAtomicLoad:
	case OpAtomicStore:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_atomic(ops, instruction.length, opcode);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpControlBarrier:
	case OpMemoryBarrier:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t memory;
		uint32_t semantics;

		if (opcode == OpMemoryBarrier)
		{
			memory = evaluate_constant_u32(ops[0]);
			semantics = evaluate_constant_u32(ops[1]);
		}
		else
		{
			memory = evaluate_constant_u32(ops[1]);
			semantics = evaluate_constant_u32(ops[2]);
		}

		if (memory == ScopeSubgroup)
		{
			// No Wave-barriers in HLSL.
			break;
		}

		// We only care about these flags, acquire/release and friends are not relevant to GLSL.
		semantics = mask_relevant_memory_semantics(semantics);

		if (opcode == OpMemoryBarrier)
		{
			// If we are a memory barrier, and the next instruction is a control barrier, check if that memory barrier
			// does what we need, so we avoid redundant barriers.
			const Instruction *next = get_next_instruction_in_block(instruction);
			if (next && next->op == OpControlBarrier)
			{
				auto *next_ops = stream(*next);
				uint32_t next_memory = evaluate_constant_u32(next_ops[1]);
				uint32_t next_semantics = evaluate_constant_u32(next_ops[2]);
				next_semantics = mask_relevant_memory_semantics(next_semantics);

				// There is no "just execution barrier" in HLSL.
				// If there are no memory semantics for next instruction, we will imply group shared memory is synced.
				if (next_semantics == 0)
					next_semantics = MemorySemanticsWorkgroupMemoryMask;

				bool memory_scope_covered = false;
				if (next_memory == memory)
					memory_scope_covered = true;
				else if (next_semantics == MemorySemanticsWorkgroupMemoryMask)
				{
					// If we only care about workgroup memory, either Device or Workgroup scope is fine,
					// scope does not have to match.
					if ((next_memory == ScopeDevice || next_memory == ScopeWorkgroup) &&
					    (memory == ScopeDevice || memory == ScopeWorkgroup))
					{
						memory_scope_covered = true;
					}
				}
				else if (memory == ScopeWorkgroup && next_memory == ScopeDevice)
				{
					// The control barrier has device scope, but the memory barrier just has workgroup scope.
					memory_scope_covered = true;
				}

				// If we have the same memory scope, and all memory types are covered, we're good.
				if (memory_scope_covered && (semantics & next_semantics) == semantics)
					break;
			}
		}

		// We are synchronizing some memory or syncing execution,
		// so we cannot forward any loads beyond the memory barrier.
		if (semantics || opcode == OpControlBarrier)
		{
			assert(current_emitting_block);
			flush_control_dependent_expressions(current_emitting_block->self);
			flush_all_active_variables();
		}

		if (opcode == OpControlBarrier)
		{
			// We cannot emit just execution barrier, for no memory semantics pick the cheapest option.
			if (semantics == MemorySemanticsWorkgroupMemoryMask || semantics == 0)
				statement("GroupMemoryBarrierWithGroupSync();");
			else if (semantics != 0 && (semantics & MemorySemanticsWorkgroupMemoryMask) == 0)
				statement("DeviceMemoryBarrierWithGroupSync();");
			else
				statement("AllMemoryBarrierWithGroupSync();");
		}
		else
		{
			if (semantics == MemorySemanticsWorkgroupMemoryMask)
				statement("GroupMemoryBarrier();");
			else if (semantics != 0 && (semantics & MemorySemanticsWorkgroupMemoryMask) == 0)
				statement("DeviceMemoryBarrier();");
			else
				statement("AllMemoryBarrier();");
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitFieldInsert:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (!requires_bitfield_insert)
		{
			requires_bitfield_insert = true;
			force_recompile();
		}

		auto expr = join("spvBitfieldInsert(", to_expression(ops[2]), ", ", to_expression(ops[3]), ", ",
		                 to_expression(ops[4]), ", ", to_expression(ops[5]), ")");

		bool forward =
		    should_forward(ops[2]) && should_forward(ops[3]) && should_forward(ops[4]) && should_forward(ops[5]);

		auto &restype = get<SPIRType>(ops[0]);
		expr = bitcast_expression(restype, SPIRType::UInt, expr);
		emit_op(ops[0], ops[1], expr, forward);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitFieldSExtract:
	case OpBitFieldUExtract:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (!requires_bitfield_extract)
		{
			requires_bitfield_extract = true;
			force_recompile();
		}

		if (opcode == OpBitFieldSExtract)
			HLSL_TFOP(spvBitfieldSExtract);
		else
			HLSL_TFOP(spvBitfieldUExtract);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitCount:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto basetype = expression_type(ops[2]).basetype;
		emit_unary_func_op_cast(ops[0], ops[1], ops[2], "countbits", basetype, basetype);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitReverse:
#ifndef SPIRV_CROSS_WEBMIN
		HLSL_UFOP(reversebits);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpArrayLength:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto *var = maybe_get_backing_variable(ops[2]);
		if (!var)
			SPIRV_CROSS_THROW("Array length must point directly to an SSBO block.");

		auto &type = get<SPIRType>(var->basetype);
		if (!has_decoration(type.self, DecorationBlock) && !has_decoration(type.self, DecorationBufferBlock))
			SPIRV_CROSS_THROW("Array length expression must point to a block type.");

		// This must be 32-bit uint, so we're good to go.
		emit_uninitialized_temporary_expression(ops[0], ops[1]);
		statement(to_non_uniform_aware_expression(ops[2]), ".GetDimensions(", to_expression(ops[1]), ");");
		uint32_t offset = type_struct_member_offset(type, ops[3]);
		uint32_t stride = type_struct_member_array_stride(type, ops[3]);
		statement(to_expression(ops[1]), " = (", to_expression(ops[1]), " - ", offset, ") / ", stride, ";");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpIsHelperInvocationEXT:
#ifndef SPIRV_CROSS_WEBMIN
		if (hlsl_options.shader_model < 50 || get_entry_point().model != ExecutionModelFragment)
			SPIRV_CROSS_THROW("Helper Invocation input is only supported in PS 5.0 or higher.");
		// Helper lane state with demote is volatile by nature.
		// Do not forward this.
		emit_op(ops[0], ops[1], "IsHelperLane()", false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpBeginInvocationInterlockEXT:
	case OpEndInvocationInterlockEXT:
#ifndef SPIRV_CROSS_WEBMIN
		if (hlsl_options.shader_model < 51)
			SPIRV_CROSS_THROW("Rasterizer order views require Shader Model 5.1.");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break; // Nothing to do in the body

	case OpRayQueryInitializeKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);

		std::string ray_desc_name = get_unique_identifier();
		statement("RayDesc ", ray_desc_name, " = {", to_expression(ops[4]), ", ", to_expression(ops[5]), ", ",
			to_expression(ops[6]), ", ", to_expression(ops[7]), "};");

		statement(to_expression(ops[0]), ".TraceRayInline(", 
			to_expression(ops[1]), ", ", // acc structure
			to_expression(ops[2]), ", ", // ray flags
			to_expression(ops[3]), ", ", // mask
			ray_desc_name, ");"); // ray
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryProceedKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_op(ops[0], ops[1], join(to_expression(ops[2]), ".Proceed()"), false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}	
	case OpRayQueryTerminateKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		statement(to_expression(ops[0]), ".Abort();");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGenerateIntersectionKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		statement(to_expression(ops[0]), ".CommitProceduralPrimitiveHit(", to_expression(ops[1]), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryConfirmIntersectionKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		statement(to_expression(ops[0]), ".CommitNonOpaqueTriangleHit();");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionTypeKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedStatus()", ".CandidateType()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionTKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedRayT()", ".CandidateTriangleRayT()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionInstanceCustomIndexKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedInstanceID()", ".CandidateInstanceID()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionInstanceIdKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedInstanceIndex()", ".CandidateInstanceIndex()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionInstanceShaderBindingTableRecordOffsetKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedInstanceContributionToHitGroupIndex()", 
			".CandidateInstanceContributionToHitGroupIndex()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionGeometryIndexKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedGeometryIndex()",
				".CandidateGeometryIndex()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionPrimitiveIndexKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedPrimitiveIndex()", ".CandidatePrimitiveIndex()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionBarycentricsKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedTriangleBarycentrics()", ".CandidateTriangleBarycentrics()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionFrontFaceKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedTriangleFrontFace()", ".CandidateTriangleFrontFace()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionCandidateAABBOpaqueKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_op(ops[0], ops[1], join(to_expression(ops[2]), ".CandidateProceduralPrimitiveNonOpaque()"), false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionObjectRayDirectionKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedObjectRayDirection()", ".CandidateObjectRayDirection()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionObjectRayOriginKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_rayquery_function(".CommittedObjectRayOrigin()", ".CandidateObjectRayOrigin()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionObjectToWorldKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedObjectToWorld4x3()", ".CandidateObjectToWorld4x3()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetIntersectionWorldToObjectKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_rayquery_function(".CommittedWorldToObject4x3()", ".CandidateWorldToObject4x3()", ops);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetRayFlagsKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_op(ops[0], ops[1], join(to_expression(ops[2]), ".RayFlags()"), false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetRayTMinKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_op(ops[0], ops[1], join(to_expression(ops[2]), ".RayTMin()"), false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetWorldRayOriginKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_op(ops[0], ops[1], join(to_expression(ops[2]), ".WorldRayOrigin()"), false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpRayQueryGetWorldRayDirectionKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_op(ops[0], ops[1], join(to_expression(ops[2]), ".WorldRayDirection()"), false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	case OpSetMeshOutputsEXT:
	{
#ifndef SPIRV_CROSS_WEBMIN
		statement("SetMeshOutputCounts(", to_unpacked_expression(ops[0]), ", ", to_unpacked_expression(ops[1]), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}
	default:
		CompilerGLSL_emit_instruction(instruction);
		break;
	}
}

void CompilerHLSL::set_root_constant_layouts(std::vector<RootConstants> layout)
{
	root_constants_layout = std::move(layout);
}

void CompilerHLSL::add_vertex_attribute_remap(const HLSLVertexAttributeRemap &vertex_attributes)
{
	remap_vertex_attributes.push_back(vertex_attributes);
}

void CompilerHLSL::validate_shader_model()
{
	// Check for nonuniform qualifier.
	// Instead of looping over all decorations to find this, just look at capabilities.
	for (auto &cap : ir.declared_capabilities)
	{
		switch (cap)
		{
		case CapabilityShaderNonUniformEXT:
		case CapabilityRuntimeDescriptorArrayEXT:
			if (hlsl_options.shader_model < 51)
				SPIRV_CROSS_THROW(
				    "Shader model 5.1 or higher is required to use bindless resources or NonUniformResourceIndex.");
			break;

		case CapabilityVariablePointers:
		case CapabilityVariablePointersStorageBuffer:
			SPIRV_CROSS_THROW("VariablePointers capability is not supported in HLSL.");

		default:
			break;
		}
	}

	if (ir.addressing_model != AddressingModelLogical)
		SPIRV_CROSS_THROW("Only Logical addressing model can be used with HLSL.");

	if (hlsl_options.enable_16bit_types && hlsl_options.shader_model < 62)
		SPIRV_CROSS_THROW("Need at least shader model 6.2 when enabling native 16-bit type support.");
}

string CompilerHLSL::compile()
{
	ir.fixup_reserved_names();

	// Do not deal with ES-isms like precision, older extensions and such.
	options.es = false;
	options.version = 450;
	options.vulkan_semantics = true;
	backend.float_literal_suffix = true;
	backend.double_literal_suffix = false;
	backend.long_long_literal_suffix = true;
	backend.uint32_t_literal_suffix = true;
	backend.int16_t_literal_suffix = "";
	backend.uint16_t_literal_suffix = "u";
	backend.basic_int_type = "int";
	backend.basic_uint_type = "uint";
	backend.demote_literal = "discard";
	backend.boolean_mix_function = "";
	backend.swizzle_is_function = false;
	backend.shared_is_implied = true;
	backend.unsized_array_supported = true;
	backend.explicit_struct_type = false;
	backend.use_initializer_list = true;
	backend.use_constructor_splatting = false;
	backend.can_swizzle_scalar = true;
	backend.can_declare_struct_inline = false;
	backend.can_declare_arrays_inline = false;
	backend.can_return_array = false;
	backend.nonuniform_qualifier = "NonUniformResourceIndex";
	backend.support_case_fallthrough = false;
	backend.force_merged_mesh_block = get_execution_model() == ExecutionModelMeshEXT;
	backend.force_gl_in_out_block = backend.force_merged_mesh_block;

	// SM 4.1 does not support precise for some reason.
	backend.support_precise_qualifier = hlsl_options.shader_model >= 50 || hlsl_options.shader_model == 40;

	fixup_anonymous_struct_names();
	fixup_type_alias();
	reorder_type_alias();
	build_function_control_flow_graphs_and_analyze();
	validate_shader_model();
	update_active_builtins();
	analyze_image_and_sampler_usage();
	analyze_interlocked_resource_usage();
	if (get_execution_model() == ExecutionModelMeshEXT)
		analyze_meshlet_writes();

	// Subpass input needs SV_Position.
	if (need_subpass_input)
		active_input_builtins.set(BuiltInFragCoord);

	uint32_t pass_count = 0;
	do
	{
		reset(pass_count);

		// Move constructor for this type is broken on GCC 4.9 ...
		buffer.reset();

		emit_header();
		emit_resources();

		emit_function(get<SPIRFunction>(ir.default_entry_point), Bitset());
		emit_hlsl_entry_point();

		pass_count++;
	} while (is_forcing_recompilation());

	// Entry point in HLSL is always main() for the time being.
	get_entry_point().name = "main";

	return buffer.str();
}

void CompilerHLSL::emit_block_hints(const SPIRBlock &block)
{
	switch (block.hint)
	{
	case SPIRBlock::HintFlatten:
		statement("[flatten]");
		break;
	case SPIRBlock::HintDontFlatten:
		statement("[branch]");
		break;
	case SPIRBlock::HintUnroll:
		statement("[unroll]");
		break;
	case SPIRBlock::HintDontUnroll:
		statement("[loop]");
		break;
	default:
		break;
	}
}

bool CompilerHLSL::builtin_translates_to_nonarray(spv::BuiltIn builtin) const
{
	return (builtin == BuiltInSampleMask);
}

bool CompilerHLSL::is_user_type_structured(uint32_t id) const
{
	if (hlsl_options.preserve_structured_buffers)
	{
		// Compare left hand side of string only as these user types can contain more meta data such as their subtypes,
		// e.g. "structuredbuffer:int"
		const std::string &user_type = get_decoration_string(id, DecorationUserTypeGOOGLE);
		return user_type.compare(0, 16, "structuredbuffer") == 0 ||
		       user_type.compare(0, 18, "rwstructuredbuffer") == 0 ||
		       user_type.compare(0, 33, "rasterizerorderedstructuredbuffer") == 0;
	}
	return false;
}

// GLSL Implementation

void CompilerHLSL::add_resource_name(uint32_t id)
{
	add_variable(resource_names, block_names, ir.meta[id].decoration.alias);
}

string CompilerHLSL::variable_decl(const SPIRVariable &variable)
{
	// Ignore the pointer type since GLSL doesn't have pointers.
	auto &type = get_variable_data_type(variable);

	if (type.pointer_depth > 1 && !backend.support_pointer_to_pointer)
		SPIRV_CROSS_THROW("Cannot declare pointer-to-pointer types.");

	auto res = join(to_qualifiers_glsl(variable.self), variable_decl(type, to_name(variable.self), variable.self));

	if (variable.loop_variable && variable.static_expression)
	{
		uint32_t expr = variable.static_expression;
		if (ir.ids[expr].get_type() != TypeUndef)
			res += join(" = ", to_unpacked_expression(variable.static_expression));
		else if (options.force_zero_initialized_variables && type_can_zero_initialize(type))
			res += join(" = ", to_zero_initialized_expression(get_variable_data_type_id(variable)));
	}
	else if (variable.initializer && !variable_decl_is_remapped_storage(variable, StorageClassWorkgroup))
	{
		uint32_t expr = variable.initializer;
		if (ir.ids[expr].get_type() != TypeUndef)
			res += join(" = ", to_initializer_expression(variable));
		else if (options.force_zero_initialized_variables && type_can_zero_initialize(type))
			res += join(" = ", to_zero_initialized_expression(get_variable_data_type_id(variable)));
	}

	return res;
}

string CompilerHLSL::variable_decl(const SPIRType &type, const string &name, uint32_t id)
{
	string type_name = type_to_glsl(type, id);
	remap_variable_type_name(type, name, type_name);
	return join(type_name, " ", name, type_to_array_glsl(type));
}

string CompilerHLSL::constant_expression(const SPIRConstant &c,
                                         bool inside_block_like_struct_scope,
                                         bool inside_struct_scope)
{
	auto &type = get<SPIRType>(c.constant_type);

	if (type_is_top_level_pointer(type))
	{
		return backend.null_pointer_literal;
	}
	else if (!c.subconstants.empty())
	{
		// Handles Arrays and structures.
		string res;

		// Only consider the decay if we are inside a struct scope where we are emitting a member with Offset decoration.
		// Outside a block-like struct declaration, we can always bind to a constant array with templated type.
		// Should look at ArrayStride here as well, but it's possible to declare a constant struct
		// with Offset = 0, using no ArrayStride on the enclosed array type.
		// A particular CTS test hits this scenario.
		bool array_type_decays = inside_block_like_struct_scope &&
		                         type_is_top_level_array(type) &&
		                         !backend.array_is_value_type_in_buffer_blocks;

		// Allow Metal to use the array<T> template to make arrays a value type
		bool needs_trailing_tracket = false;
		if (backend.use_initializer_list && backend.use_typed_initializer_list && type.basetype == SPIRType::Struct &&
		    !type_is_top_level_array(type))
		{
			res = type_to_glsl_constructor(type) + "{ ";
		}
		else if (backend.use_initializer_list && backend.use_typed_initializer_list && backend.array_is_value_type &&
		         type_is_top_level_array(type) && !array_type_decays)
		{
			const auto *p_type = &type;
			SPIRType tmp_type;

			if (inside_struct_scope &&
			    backend.boolean_in_struct_remapped_type != SPIRType::Boolean &&
			    type.basetype == SPIRType::Boolean)
			{
				tmp_type = type;
				tmp_type.basetype = backend.boolean_in_struct_remapped_type;
				p_type = &tmp_type;
			}

			res = type_to_glsl_constructor(*p_type) + "({ ";
			needs_trailing_tracket = true;
		}
		else if (backend.use_initializer_list)
		{
			res = "{ ";
		}
		else
		{
			res = type_to_glsl_constructor(type) + "(";
		}

		uint32_t subconstant_index = 0;
		for (auto &elem : c.subconstants)
		{
			if (auto *op = maybe_get<SPIRConstantOp>(elem))
			{
				res += constant_op_expression(*op);
			}
			else if (maybe_get<SPIRUndef>(elem) != nullptr)
			{
				res += to_name(elem);
			}
			else
			{
				auto &subc = get<SPIRConstant>(elem);
				if (subc.specialization && !expression_is_forwarded(elem))
					res += to_name(elem);
				else
				{
					if (!type_is_top_level_array(type) && type.basetype == SPIRType::Struct)
					{
						// When we get down to emitting struct members, override the block-like information.
						// For constants, we can freely mix and match block-like state.
						inside_block_like_struct_scope =
						    has_member_decoration(type.self, subconstant_index, DecorationOffset);
					}

					if (type.basetype == SPIRType::Struct)
						inside_struct_scope = true;

					res += constant_expression(subc, inside_block_like_struct_scope, inside_struct_scope);
				}
			}

			if (&elem != &c.subconstants.back())
				res += ", ";

			subconstant_index++;
		}

		res += backend.use_initializer_list ? " }" : ")";
		if (needs_trailing_tracket)
			res += ")";

		return res;
	}
	else if (type.basetype == SPIRType::Struct && type.member_types.size() == 0)
	{
		// Metal tessellation likes empty structs which are then constant expressions.
		if (backend.supports_empty_struct)
			return "{ }";
		else if (backend.use_typed_initializer_list)
			return join(type_to_glsl(type), "{ 0 }");
		else if (backend.use_initializer_list)
			return "{ 0 }";
		else
			return join(type_to_glsl(type), "(0)");
	}
	else if (c.columns() == 1)
	{
		auto res = constant_expression_vector(c, 0);

		if (inside_struct_scope &&
		    backend.boolean_in_struct_remapped_type != SPIRType::Boolean &&
		    type.basetype == SPIRType::Boolean)
		{
			SPIRType tmp_type = type;
			tmp_type.basetype = backend.boolean_in_struct_remapped_type;
			res = join(type_to_glsl(tmp_type), "(", res, ")");
		}

		return res;
	}
	else
	{
		string res = type_to_glsl(type) + "(";
		for (uint32_t col = 0; col < c.columns(); col++)
		{
			if (c.specialization_constant_id(col) != 0)
				res += to_name(c.specialization_constant_id(col));
			else
				res += constant_expression_vector(c, col);

			if (col + 1 < c.columns())
				res += ", ";
		}
		res += ")";

		if (inside_struct_scope &&
		    backend.boolean_in_struct_remapped_type != SPIRType::Boolean &&
		    type.basetype == SPIRType::Boolean)
		{
			SPIRType tmp_type = type;
			tmp_type.basetype = backend.boolean_in_struct_remapped_type;
			res = join(type_to_glsl(tmp_type), "(", res, ")");
		}

		return res;
	}
}


string CompilerHLSL::to_member_name(const SPIRType &type, uint32_t index)
{
	if (type.type_alias != TypeID(0) &&
	    !has_extended_decoration(type.type_alias, SPIRVCrossDecorationBufferBlockRepacked))
	{
		return to_member_name(get<SPIRType>(type.type_alias), index);
	}

	auto &memb = ir.meta[type.self].members;
	if (index < memb.size() && !memb[index].alias.empty())
		return memb[index].alias;
	else
		return join("_m", index);
}

string CompilerHLSL::type_to_array_glsl(const SPIRType &type)
{
	if (type.pointer && type.storage == StorageClassPhysicalStorageBufferEXT && type.basetype != SPIRType::Struct)
	{
		// We are using a wrapped pointer type, and we should not emit any array declarations here.
		return "";
	}

	if (type.array.empty())
		return "";

	if (options.flatten_multidimensional_arrays)
	{
		string res;
		res += "[";
		for (auto i = uint32_t(type.array.size()); i; i--)
		{
			res += enclose_expression(to_array_size(type, i - 1));
			if (i > 1)
				res += " * ";
		}
		res += "]";
		return res;
	}
	else
	{
		if (type.array.size() > 1)
		{
			if (!options.es && options.version < 430)
				require_extension_internal("GL_ARB_arrays_of_arrays");
			else if (options.es && options.version < 310)
				SPIRV_CROSS_THROW("Arrays of arrays not supported before ESSL version 310. "
				                  "Try using --flatten-multidimensional-arrays or set "
				                  "options.flatten_multidimensional_arrays to true.");
		}

		string res;
		for (auto i = uint32_t(type.array.size()); i; i--)
		{
			res += "[";
			res += to_array_size(type, i - 1);
			res += "]";
		}
		return res;
	}
}

string CompilerHLSL::to_expression(uint32_t id, bool register_expression_read)
{
	auto itr = invalid_expressions.find(id);
	if (itr != end(invalid_expressions))
		handle_invalid_expression(id);

	if (ir.ids[id].get_type() == TypeExpression)
	{
		// We might have a more complex chain of dependencies.
		// A possible scenario is that we
		//
		// %1 = OpLoad
		// %2 = OpDoSomething %1 %1. here %2 will have a dependency on %1.
		// %3 = OpDoSomethingAgain %2 %2. Here %3 will lose the link to %1 since we don't propagate the dependencies like that.
		// OpStore %1 %foo // Here we can invalidate %1, and hence all expressions which depend on %1. Only %2 will know since it's part of invalid_expressions.
		// %4 = OpDoSomethingAnotherTime %3 %3 // If we forward all expressions we will see %1 expression after store, not before.
		//
		// However, we can propagate up a list of depended expressions when we used %2, so we can check if %2 is invalid when reading %3 after the store,
		// and see that we should not forward reads of the original variable.
		auto &expr = get<SPIRExpression>(id);
		for (uint32_t dep : expr.expression_dependencies)
			if (invalid_expressions.find(dep) != end(invalid_expressions))
				handle_invalid_expression(dep);
	}

	if (register_expression_read)
		track_expression_read(id);

	switch (ir.ids[id].get_type())
	{
	case TypeExpression:
	{
		auto &e = get<SPIRExpression>(id);
		if (e.base_expression)
			return to_enclosed_expression(e.base_expression) + e.expression;
		else if (e.need_transpose)
		{
			// This should not be reached for access chains, since we always deal explicitly with transpose state
			// when consuming an access chain expression.
			uint32_t physical_type_id = get_extended_decoration(id, SPIRVCrossDecorationPhysicalTypeID);
			bool is_packed = has_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked);
			bool relaxed = has_decoration(id, DecorationRelaxedPrecision);
			return convert_row_major_matrix(e.expression, get<SPIRType>(e.expression_type), physical_type_id,
			                                is_packed, relaxed);
		}
		else if (flattened_structs.count(id))
		{
			return load_flattened_struct(e.expression, get<SPIRType>(e.expression_type));
		}
		else
		{
			if (is_forcing_recompilation())
			{
				// During first compilation phase, certain expression patterns can trigger exponential growth of memory.
				// Avoid this by returning dummy expressions during this phase.
				// Do not use empty expressions here, because those are sentinels for other cases.
				return "_";
			}
			else
				return e.expression;
		}
	}

	case TypeConstant:
	{
		auto &c = get<SPIRConstant>(id);
		auto &type = get<SPIRType>(c.constant_type);

		// WorkGroupSize may be a constant.
		if (has_decoration(c.self, DecorationBuiltIn))
			return builtin_to_glsl(BuiltIn(get_decoration(c.self, DecorationBuiltIn)), StorageClassGeneric);
		else if (c.specialization)
		{
			if (backend.workgroup_size_is_hidden)
			{
				int wg_index = get_constant_mapping_to_workgroup_component(c);
				if (wg_index >= 0)
				{
					auto wg_size = join(builtin_to_glsl(BuiltInWorkgroupSize, StorageClassInput), vector_swizzle(1, wg_index));
					if (type.basetype != SPIRType::UInt)
						wg_size = bitcast_expression(type, SPIRType::UInt, wg_size);
					return wg_size;
				}
			}

			if (expression_is_forwarded(id))
				return constant_expression(c);

			return to_name(id);
		}
		else if (c.is_used_as_lut)
			return to_name(id);
		else if (type.basetype == SPIRType::Struct && !backend.can_declare_struct_inline)
			return to_name(id);
		else if (!type.array.empty() && !backend.can_declare_arrays_inline)
			return to_name(id);
		else
			return constant_expression(c);
	}

	case TypeConstantOp:
		return to_name(id);

	case TypeVariable:
	{
		auto &var = get<SPIRVariable>(id);
		// If we try to use a loop variable before the loop header, we have to redirect it to the static expression,
		// the variable has not been declared yet.
		if (var.statically_assigned || (var.loop_variable && !var.loop_variable_enable))
		{
			// We might try to load from a loop variable before it has been initialized.
			// Prefer static expression and fallback to initializer.
			if (var.static_expression)
				return to_expression(var.static_expression);
			else if (var.initializer)
				return to_expression(var.initializer);
			else
			{
				// We cannot declare the variable yet, so have to fake it.
				uint32_t undef_id = ir.increase_bound_by(1);
				return emit_uninitialized_temporary_expression(get_variable_data_type_id(var), undef_id).expression;
			}
		}
		else if (var.deferred_declaration)
		{
			var.deferred_declaration = false;
			return variable_decl(var);
		}
		else if (flattened_structs.count(id))
		{
			return load_flattened_struct(to_name(id), get<SPIRType>(var.basetype));
		}
		else
		{
			auto &dec = ir.meta[var.self].decoration;
			if (dec.builtin)
				return builtin_to_glsl(dec.builtin_type, var.storage);
			else
				return to_name(id);
		}
	}

	case TypeCombinedImageSampler:
		// This type should never be taken the expression of directly.
		// The intention is that texture sampling functions will extract the image and samplers
		// separately and take their expressions as needed.
		// GLSL does not use this type because OpSampledImage immediately creates a combined image sampler
		// expression ala sampler2D(texture, sampler).
		SPIRV_CROSS_THROW("Combined image samplers have no default expression representation.");

	case TypeAccessChain:
		// We cannot express this type. They only have meaning in other OpAccessChains, OpStore or OpLoad.
		SPIRV_CROSS_THROW("Access chains have no default expression representation.");

	default:
		return to_name(id);
	}
}

void CompilerHLSL::begin_scope()
{
	statement("{");
	indent++;
}

void CompilerHLSL::end_scope()
{
	if (!indent)
		SPIRV_CROSS_THROW("Popping empty indent stack.");
	indent--;
	statement("}");
}

void CompilerHLSL::end_scope(const string &trailer)
{
	if (!indent)
		SPIRV_CROSS_THROW("Popping empty indent stack.");
	indent--;
	statement("}", trailer);
}

void CompilerHLSL::end_scope_decl()
{
	if (!indent)
		SPIRV_CROSS_THROW("Popping empty indent stack.");
	indent--;
	statement("};");
}

void CompilerHLSL::end_scope_decl(const string &decl)
{
	if (!indent)
		SPIRV_CROSS_THROW("Popping empty indent stack.");
	indent--;
	statement("} ", decl, ";");
}

string CompilerHLSL::constant_value_macro_name(uint32_t id)
{
	return join("SPIRV_CROSS_CONSTANT_ID_", id);
}

static bool is_unsigned_opcode(Op op)
{
	// Don't have to be exhaustive, only relevant for legacy target checking ...
	switch (op)
	{
	case OpShiftRightLogical:
	case OpUGreaterThan:
	case OpUGreaterThanEqual:
	case OpULessThan:
	case OpULessThanEqual:
	case OpUConvert:
	case OpUDiv:
	case OpUMod:
	case OpUMulExtended:
	case OpConvertUToF:
	case OpConvertFToU:
		return true;

	default:
		return false;
	}
}

void CompilerHLSL::emit_struct(SPIRType &type)
{
	// Struct types can be stamped out multiple times
	// with just different offsets, matrix layouts, etc ...
	// Type-punning with these types is legal, which complicates things
	// when we are storing struct and array types in an SSBO for example.
	// If the type master is packed however, we can no longer assume that the struct declaration will be redundant.
	if (type.type_alias != TypeID(0) &&
	    !has_extended_decoration(type.type_alias, SPIRVCrossDecorationBufferBlockRepacked))
		return;

	add_resource_name(type.self);
	auto name = type_to_glsl(type);

	statement(!backend.explicit_struct_type ? "struct " : "", name);
	begin_scope();

	type.member_name_cache.clear();

	uint32_t i = 0;
	bool emitted = false;
	for (auto &member : type.member_types)
	{
		add_member_name(type, i);
		emit_struct_member(type, member, i);
		i++;
		emitted = true;
	}

	// Don't declare empty structs in GLSL, this is not allowed.
	if (type_is_empty(type) && !backend.supports_empty_struct)
	{
		statement("int empty_struct_member;");
		emitted = true;
	}

	if (has_extended_decoration(type.self, SPIRVCrossDecorationPaddingTarget))
		emit_struct_padding_target(type);

	end_scope_decl();

	if (emitted)
		statement("");
}

bool CompilerHLSL::is_per_primitive_variable(const SPIRVariable &var) const
{
	if (has_decoration(var.self, DecorationPerPrimitiveEXT))
		return true;

	auto &type = get<SPIRType>(var.basetype);
	if (!has_decoration(type.self, DecorationBlock))
		return false;

	for (uint32_t i = 0, n = uint32_t(type.member_types.size()); i < n; i++)
		if (!has_member_decoration(type.self, i, DecorationPerPrimitiveEXT))
			return false;

	return true;
}

bool CompilerHLSL::variable_is_lut(const SPIRVariable &var) const
{
	bool statically_assigned = var.statically_assigned && var.static_expression != ID(0) && var.remapped_variable;

	if (statically_assigned)
	{
		auto *constant = maybe_get<SPIRConstant>(var.static_expression);
		if (constant && constant->is_used_as_lut)
			return true;
	}

	return false;
}

void CompilerHLSL::flush_variable_declaration(uint32_t id)
{
	// Ensure that we declare phi-variable copies even if the original declaration isn't deferred
	auto *var = maybe_get<SPIRVariable>(id);
	if (var && var->deferred_declaration)
	{
		string initializer;
		if (options.force_zero_initialized_variables &&
		    (var->storage == StorageClassFunction || var->storage == StorageClassGeneric ||
		     var->storage == StorageClassPrivate) &&
		    !var->initializer && type_can_zero_initialize(get_variable_data_type(*var)))
		{
			initializer = join(" = ", to_zero_initialized_expression(get_variable_data_type_id(*var)));
		}

		statement(variable_decl_function_local(*var), initializer, ";");
		var->deferred_declaration = false;
	}
	if (var)
	{
		emit_variable_temporary_copies(*var);
	}
}

string CompilerHLSL::to_unpacked_expression(uint32_t id, bool register_expression_read)
{
	// If we need to transpose, it will also take care of unpacking rules.
	auto *e = maybe_get<SPIRExpression>(id);
	bool need_transpose = e && e->need_transpose;
	bool is_remapped = has_extended_decoration(id, SPIRVCrossDecorationPhysicalTypeID);
	bool is_packed = has_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked);

	if (!need_transpose && (is_remapped || is_packed))
	{
		return unpack_expression_type(to_expression(id, register_expression_read),
		                              get_pointee_type(expression_type_id(id)),
		                              get_extended_decoration(id, SPIRVCrossDecorationPhysicalTypeID),
		                              has_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked), false);
	}
	else
		return to_expression(id, register_expression_read);
}

void CompilerHLSL::add_variable(unordered_set<string> &variables_primary,
                                const unordered_set<string> &variables_secondary, string &name)
{
	if (name.empty())
		return;

	ParsedIR::sanitize_underscores(name);
	if (ParsedIR::is_globally_reserved_identifier(name, true))
	{
		name.clear();
		return;
	}

	update_name_cache(variables_primary, variables_secondary, name);
}

bool CompilerHLSL::buffer_is_packing_standard(const SPIRType &type, BufferPackingStandard packing,
                                              uint32_t *failed_validation_index, uint32_t start_offset,
                                              uint32_t end_offset)
{
	// This is very tricky and error prone, but try to be exhaustive and correct here.
	// SPIR-V doesn't directly say if we're using std430 or std140.
	// SPIR-V communicates this using Offset and ArrayStride decorations (which is what really matters),
	// so we have to try to infer whether or not the original GLSL source was std140 or std430 based on this information.
	// We do not have to consider shared or packed since these layouts are not allowed in Vulkan SPIR-V (they are useless anyways, and custom offsets would do the same thing).
	//
	// It is almost certain that we're using std430, but it gets tricky with arrays in particular.
	// We will assume std430, but infer std140 if we can prove the struct is not compliant with std430.
	//
	// The only two differences between std140 and std430 are related to padding alignment/array stride
	// in arrays and structs. In std140 they take minimum vec4 alignment.
	// std430 only removes the vec4 requirement.

	uint32_t offset = 0;
	uint32_t pad_alignment = 1;

	bool is_top_level_block =
	    has_decoration(type.self, DecorationBlock) || has_decoration(type.self, DecorationBufferBlock);

	for (uint32_t i = 0; i < type.member_types.size(); i++)
	{
		auto &memb_type = get<SPIRType>(type.member_types[i]);
		auto member_flags = ir.meta[type.self].members[i].decoration_flags;

		// Verify alignment rules.
		uint32_t packed_alignment = type_to_packed_alignment(memb_type, member_flags, packing);

		// This is a rather dirty workaround to deal with some cases of OpSpecConstantOp used as array size, e.g:
		// layout(constant_id = 0) const int s = 10;
		// const int S = s + 5; // SpecConstantOp
		// buffer Foo { int data[S]; }; // <-- Very hard for us to deduce a fixed value here,
		// we would need full implementation of compile-time constant folding. :(
		// If we are the last member of a struct, there might be cases where the actual size of that member is irrelevant
		// for our analysis (e.g. unsized arrays).
		// This lets us simply ignore that there are spec constant op sized arrays in our buffers.
		// Querying size of this member will fail, so just don't call it unless we have to.
		//
		// This is likely "best effort" we can support without going into unacceptably complicated workarounds.
		bool member_can_be_unsized =
		    is_top_level_block && size_t(i + 1) == type.member_types.size() && !memb_type.array.empty();

		uint32_t packed_size = 0;
		if (!member_can_be_unsized || packing_is_hlsl(packing))
			packed_size = type_to_packed_size(memb_type, member_flags, packing);

		// We only need to care about this if we have non-array types which can straddle the vec4 boundary.
		uint32_t actual_offset = type_struct_member_offset(type, i);

		if (packing_is_hlsl(packing))
		{
			// If a member straddles across a vec4 boundary, alignment is actually vec4.
			uint32_t begin_word = actual_offset / 16;
			uint32_t end_word = (actual_offset + packed_size - 1) / 16;
			if (begin_word != end_word)
				packed_alignment = max<uint32_t>(packed_alignment, 16u);
		}

		// Field is not in the specified range anymore and we can ignore any further fields.
		if (actual_offset >= end_offset)
			break;

		uint32_t alignment = max(packed_alignment, pad_alignment);
		offset = (offset + alignment - 1) & ~(alignment - 1);

		// The next member following a struct member is aligned to the base alignment of the struct that came before.
		// GL 4.5 spec, 7.6.2.2.
		if (memb_type.basetype == SPIRType::Struct && !memb_type.pointer)
			pad_alignment = packed_alignment;
		else
			pad_alignment = 1;

		// Only care about packing if we are in the given range
		if (actual_offset >= start_offset)
		{
			// We only care about offsets in std140, std430, etc ...
			// For EnhancedLayout variants, we have the flexibility to choose our own offsets.
			if (!packing_has_flexible_offset(packing))
			{
				if (actual_offset != offset) // This cannot be the packing we're looking for.
				{
					if (failed_validation_index)
						*failed_validation_index = i;
					return false;
				}
			}
			else if ((actual_offset & (alignment - 1)) != 0)
			{
				// We still need to verify that alignment rules are observed, even if we have explicit offset.
				if (failed_validation_index)
					*failed_validation_index = i;
				return false;
			}

			// Verify array stride rules.
			if (type_is_top_level_array(memb_type) &&
			    type_to_packed_array_stride(memb_type, member_flags, packing) !=
			    type_struct_member_array_stride(type, i))
			{
				if (failed_validation_index)
					*failed_validation_index = i;
				return false;
			}

			// Verify that sub-structs also follow packing rules.
			// We cannot use enhanced layouts on substructs, so they better be up to spec.
			auto substruct_packing = packing_to_substruct_packing(packing);

			if (!memb_type.pointer && !memb_type.member_types.empty() &&
			    !buffer_is_packing_standard(memb_type, substruct_packing))
			{
				if (failed_validation_index)
					*failed_validation_index = i;
				return false;
			}
		}

		// Bump size.
		offset = actual_offset + packed_size;
	}

	return true;
}

SPIRExpression &CompilerHLSL::emit_op(uint32_t result_type, uint32_t result_id, const string &rhs, bool forwarding,
                                      bool suppress_usage_tracking)
{
	if (forwarding && (forced_temporaries.find(result_id) == end(forced_temporaries)))
	{
		// Just forward it without temporary.
		// If the forward is trivial, we do not force flushing to temporary for this expression.
		forwarded_temporaries.insert(result_id);
		if (suppress_usage_tracking)
			suppressed_usage_tracking.insert(result_id);

		return set<SPIRExpression>(result_id, rhs, result_type, true);
	}
	else
	{
		// If expression isn't immutable, bind it to a temporary and make the new temporary immutable (they always are).
		statement(declare_temporary(result_type, result_id), rhs, ";");
		return set<SPIRExpression>(result_id, to_name(result_id), result_type, true);
	}
}

void CompilerHLSL::preserve_alias_on_reset(uint32_t id)
{
	preserved_aliases[id] = get_name(id);
}

void CompilerHLSL::add_member_name(SPIRType &type, uint32_t index)
{
	auto &memb = ir.meta[type.self].members;
	if (index < memb.size() && !memb[index].alias.empty())
	{
		auto &name = memb[index].alias;
		if (name.empty())
			return;

		ParsedIR::sanitize_identifier(name, true, true);
		update_name_cache(type.member_name_cache, name);
	}
}

string CompilerHLSL::to_non_uniform_aware_expression(uint32_t id)
{
	string expr = to_expression(id);

	if (has_decoration(id, DecorationNonUniform))
		convert_non_uniform_expression(expr, id);

	return expr;
}

void CompilerHLSL::add_function_overload(const SPIRFunction &func)
{
	Hasher hasher;
	for (auto &arg : func.arguments)
	{
		// Parameters can vary with pointer type or not,
		// but that will not change the signature in GLSL/HLSL,
		// so strip the pointer type before hashing.
		uint32_t type_id = get_pointee_type_id(arg.type);
		auto &type = get<SPIRType>(type_id);

		if (!combined_image_samplers.empty())
		{
			// If we have combined image samplers, we cannot really trust the image and sampler arguments
			// we pass down to callees, because they may be shuffled around.
			// Ignore these arguments, to make sure that functions need to differ in some other way
			// to be considered different overloads.
			if (type.basetype == SPIRType::SampledImage ||
			    (type.basetype == SPIRType::Image && type.image.sampled == 1) || type.basetype == SPIRType::Sampler)
			{
				continue;
			}
		}

		hasher.u32(type_id);
	}
	uint64_t types_hash = hasher.get();

	auto function_name = to_name(func.self);
	auto itr = function_overloads.find(function_name);
	if (itr != end(function_overloads))
	{
		// There exists a function with this name already.
		auto &overloads = itr->second;
		if (overloads.count(types_hash) != 0)
		{
			// Overload conflict, assign a new name.
			add_resource_name(func.self);
			function_overloads[to_name(func.self)].insert(types_hash);
		}
		else
		{
			// Can reuse the name.
			overloads.insert(types_hash);
		}
	}
	else
	{
		// First time we see this function name.
		add_resource_name(func.self);
		function_overloads[to_name(func.self)].insert(types_hash);
	}
}

string CompilerHLSL::flags_to_qualifiers_glsl(const SPIRType &type, const Bitset &flags)
{
	// GL_EXT_buffer_reference variables can be marked as restrict.
	if (flags.get(DecorationRestrictPointerEXT))
		return "restrict ";

	string qual;

	if (type_is_floating_point(type) && flags.get(DecorationNoContraction) && backend.support_precise_qualifier)
		qual = "precise ";

	// Structs do not have precision qualifiers, neither do doubles (desktop only anyways, so no mediump/highp).
	bool type_supports_precision =
			type.basetype == SPIRType::Float || type.basetype == SPIRType::Int || type.basetype == SPIRType::UInt ||
			type.basetype == SPIRType::Image || type.basetype == SPIRType::SampledImage ||
			type.basetype == SPIRType::Sampler;

	if (!type_supports_precision)
		return qual;

	if (options.es)
	{
		auto &execution = get_entry_point();

		if (flags.get(DecorationRelaxedPrecision))
		{
			bool implied_fmediump = type.basetype == SPIRType::Float &&
			                        options.fragment.default_float_precision == OptionsGLSL::Mediump &&
			                        execution.model == ExecutionModelFragment;

			bool implied_imediump = (type.basetype == SPIRType::Int || type.basetype == SPIRType::UInt) &&
			                        options.fragment.default_int_precision == OptionsGLSL::Mediump &&
			                        execution.model == ExecutionModelFragment;

			qual += (implied_fmediump || implied_imediump) ? "" : "mediump ";
		}
		else
		{
			bool implied_fhighp =
			    type.basetype == SPIRType::Float && ((options.fragment.default_float_precision == OptionsGLSL::Highp &&
			                                          execution.model == ExecutionModelFragment) ||
			                                         (execution.model != ExecutionModelFragment));

			bool implied_ihighp = (type.basetype == SPIRType::Int || type.basetype == SPIRType::UInt) &&
			                      ((options.fragment.default_int_precision == OptionsGLSL::Highp &&
			                        execution.model == ExecutionModelFragment) ||
			                       (execution.model != ExecutionModelFragment));

			qual += (implied_fhighp || implied_ihighp) ? "" : "highp ";
		}
	}
	else if (backend.allow_precision_qualifiers)
	{
		// Vulkan GLSL supports precision qualifiers, even in desktop profiles, which is convenient.
		// The default is highp however, so only emit mediump in the rare case that a shader has these.
		if (flags.get(DecorationRelaxedPrecision))
			qual += "mediump ";
	}

	return qual;
}

bool CompilerHLSL::skip_argument(uint32_t id) const
{
	if (!combined_image_samplers.empty() || !options.vulkan_semantics)
	{
		auto &type = expression_type(id);
		if (type.basetype == SPIRType::Sampler || (type.basetype == SPIRType::Image && type.image.sampled == 1))
			return true;
	}
	return false;
}

void CompilerHLSL::add_local_variable_name(uint32_t id)
{
	add_variable(local_variable_names, block_names, ir.meta[id].decoration.alias);
}

string CompilerHLSL::argument_decl(const SPIRFunction::Parameter &arg)
{
	// glslangValidator seems to make all arguments pointer no matter what which is rather bizarre ...
	auto &type = expression_type(arg.id);
	const char *direction = "";

	if (type.pointer)
	{
		if (arg.write_count && arg.read_count)
			direction = "inout ";
		else if (arg.write_count)
			direction = "out ";
	}

	return join(direction, to_qualifiers_glsl(arg.id), variable_decl(type, to_name(arg.id), arg.id));
}

bool CompilerHLSL::should_forward(uint32_t id) const
{
	// If id is a variable we will try to forward it regardless of force_temporary check below
	// This is important because otherwise we'll get local sampler copies (highp sampler2D foo = bar) that are invalid in OpenGL GLSL

	auto *var = maybe_get<SPIRVariable>(id);
	if (var)
	{
		// Never forward volatile builtin variables, e.g. SPIR-V 1.6 HelperInvocation.
		return !(has_decoration(id, DecorationBuiltIn) && has_decoration(id, DecorationVolatile));
	}

	// For debugging emit temporary variables for all expressions
	if (options.force_temporary)
		return false;

	// If an expression carries enough dependencies we need to stop forwarding at some point,
	// or we explode compilers. There are usually limits to how much we can nest expressions.
	auto *expr = maybe_get<SPIRExpression>(id);
	const uint32_t max_expression_dependencies = 64;
	if (expr && expr->expression_dependencies.size() >= max_expression_dependencies)
		return false;

	if (expr && expr->loaded_from
		&& has_decoration(expr->loaded_from, DecorationBuiltIn)
		&& has_decoration(expr->loaded_from, DecorationVolatile))
	{
		// Never forward volatile builtin variables, e.g. SPIR-V 1.6 HelperInvocation.
		return false;
	}

	// Immutable expression can always be forwarded.
	if (is_immutable(id))
		return true;

	return false;
}

string CompilerHLSL::to_enclosed_expression(uint32_t id, bool register_expression_read)
{
	return enclose_expression(to_expression(id, register_expression_read));
}

void CompilerHLSL::register_control_dependent_expression(uint32_t expr)
{
	if (forwarded_temporaries.find(expr) == end(forwarded_temporaries))
		return;

	assert(current_emitting_block);
	current_emitting_block->invalidate_expressions.push_back(expr);
}

uint32_t CompilerHLSL::get_integer_width_for_glsl_instruction(GLSLstd450 op, const uint32_t *ops, uint32_t length) const
{
	if (length < 1)
		return 32;

	switch (op)
	{
	case GLSLstd450SAbs:
	case GLSLstd450SSign:
	case GLSLstd450UMin:
	case GLSLstd450SMin:
	case GLSLstd450UMax:
	case GLSLstd450SMax:
	case GLSLstd450UClamp:
	case GLSLstd450SClamp:
	case GLSLstd450FindSMsb:
	case GLSLstd450FindUMsb:
		return expression_type(ops[0]).width;

	default:
	{
		// We don't need to care about other opcodes, just return 32.
		return 32;
	}
	}
}

GLSLstd450 CompilerHLSL::get_remapped_glsl_op(GLSLstd450 std450_op) const
{
	// Relax to non-NaN aware opcodes.
	if (options.relax_nan_checks)
	{
		switch (std450_op)
		{
		case GLSLstd450NClamp:
			std450_op = GLSLstd450FClamp;
			break;
		case GLSLstd450NMin:
			std450_op = GLSLstd450FMin;
			break;
		case GLSLstd450NMax:
			std450_op = GLSLstd450FMax;
			break;
		default:
			break;
		}
	}

	return std450_op;
}

void CompilerHLSL::emit_unary_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op)
{
	bool forward = should_forward(op0);
	emit_op(result_type, result_id, join(op, "(", to_unpacked_expression(op0), ")"), forward);
	inherit_expression_dependencies(result_id, op0);
}

void CompilerHLSL::emit_trinary_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                        uint32_t op2, const char *op)
{
	bool forward = should_forward(op0) && should_forward(op1) && should_forward(op2);
	emit_op(result_type, result_id,
	        join(op, "(", to_unpacked_expression(op0), ", ", to_unpacked_expression(op1), ", ",
	             to_unpacked_expression(op2), ")"),
	        forward);

	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
	inherit_expression_dependencies(result_id, op2);
}

void CompilerHLSL::emit_binary_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                       const char *op)
{
	// Opaque types (e.g. OpTypeSampledImage) must always be forwarded in GLSL
	const auto &type = get_type(result_type);
	bool must_forward = type_is_opaque_value(type);
	bool forward = must_forward || (should_forward(op0) && should_forward(op1));
	emit_op(result_type, result_id, join(op, "(", to_unpacked_expression(op0), ", ", to_unpacked_expression(op1), ")"),
	        forward);
	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
}

void CompilerHLSL::emit_unary_func_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op,
                                           SPIRType::BaseType input_type, SPIRType::BaseType expected_result_type)
{
	auto &out_type = get<SPIRType>(result_type);
	auto &expr_type = expression_type(op0);
	auto expected_type = out_type;

	// Bit-widths might be different in unary cases because we use it for SConvert/UConvert and friends.
	expected_type.basetype = input_type;
	expected_type.width = expr_type.width;

	string cast_op;
	if (expr_type.basetype != input_type)
	{
		if (expr_type.basetype == SPIRType::Boolean)
			cast_op = join(type_to_glsl(expected_type), "(", to_unpacked_expression(op0), ")");
		else
			cast_op = bitcast_glsl(expected_type, op0);
	}
	else
		cast_op = to_unpacked_expression(op0);

	string expr;
	if (out_type.basetype != expected_result_type)
	{
		expected_type.basetype = expected_result_type;
		expected_type.width = out_type.width;
		if (out_type.basetype == SPIRType::Boolean)
			expr = type_to_glsl(out_type);
		else
			expr = bitcast_glsl_op(out_type, expected_type);
		expr += '(';
		expr += join(op, "(", cast_op, ")");
		expr += ')';
	}
	else
	{
		expr += join(op, "(", cast_op, ")");
	}

	emit_op(result_type, result_id, expr, should_forward(op0));
	inherit_expression_dependencies(result_id, op0);
}

string CompilerHLSL::to_array_size(const SPIRType &type, uint32_t index)
{
	assert(type.array.size() == type.array_size_literal.size());

	auto &size = type.array[index];
	if (!type.array_size_literal[index])
		return to_expression(size);
	else if (size)
		return convert_to_string(size);
	else if (!backend.unsized_array_supported)
	{
		// For runtime-sized arrays, we can work around
		// lack of standard support for this by simply having
		// a single element array.
		//
		// Runtime length arrays must always be the last element
		// in an interface block.
		return "1";
	}
	else
		return "";
}


void CompilerHLSL::track_expression_read(uint32_t id)
{
	switch (ir.ids[id].get_type())
	{
	case TypeExpression:
	{
		auto &e = get<SPIRExpression>(id);
		for (auto implied_read : e.implied_read_expressions)
			track_expression_read(implied_read);
		break;
	}

	case TypeAccessChain:
	{
		auto &e = get<SPIRAccessChain>(id);
		for (auto implied_read : e.implied_read_expressions)
			track_expression_read(implied_read);
		break;
	}

	default:
		break;
	}

	// If we try to read a forwarded temporary more than once we will stamp out possibly complex code twice.
	// In this case, it's better to just bind the complex expression to the temporary and read that temporary twice.
	if (expression_is_forwarded(id) && !expression_suppresses_usage_tracking(id))
	{
		auto &v = expression_usage_counts[id];
		v++;

		// If we create an expression outside a loop,
		// but access it inside a loop, we're implicitly reading it multiple times.
		// If the expression in question is expensive, we should hoist it out to avoid relying on loop-invariant code motion
		// working inside the backend compiler.
		if (expression_read_implies_multiple_reads(id))
			v++;

		if (v >= 2)
		{
			//if (v == 2)
			//    fprintf(stderr, "ID %u was forced to temporary due to more than 1 expression use!\n", id);

			// Force a recompile after this pass to avoid forwarding this variable.
			force_temporary_and_recompile(id);
		}
	}
}

string CompilerHLSL::enclose_expression(const string &expr)
{
	// If this expression contains any spaces which are not enclosed by parentheses,
	// we need to enclose it so we can treat the whole string as an expression.
	// This happens when two expressions have been part of a binary op earlier.
	if (needs_enclose_expression(expr))
		return join('(', expr, ')');
	else
		return expr;
}

string CompilerHLSL::access_chain_internal(uint32_t base, const uint32_t *indices, uint32_t count,
                                           AccessChainFlags flags, AccessChainMeta *meta)
{
	string expr;

	bool index_is_literal = (flags & ACCESS_CHAIN_INDEX_IS_LITERAL_BIT) != 0;
	bool msb_is_id = (flags & ACCESS_CHAIN_LITERAL_MSB_FORCE_ID) != 0;
	bool chain_only = (flags & ACCESS_CHAIN_CHAIN_ONLY_BIT) != 0;
	bool ptr_chain = (flags & ACCESS_CHAIN_PTR_CHAIN_BIT) != 0;
	bool register_expression_read = (flags & ACCESS_CHAIN_SKIP_REGISTER_EXPRESSION_READ_BIT) == 0;
	bool flatten_member_reference = (flags & ACCESS_CHAIN_FLATTEN_ALL_MEMBERS_BIT) != 0;

	if (!chain_only)
	{
		// We handle transpose explicitly, so don't resolve that here.
		auto *e = maybe_get<SPIRExpression>(base);
		bool old_transpose = e && e->need_transpose;
		if (e)
			e->need_transpose = false;
		expr = to_enclosed_expression(base, register_expression_read);
		if (e)
			e->need_transpose = old_transpose;
	}

	// Start traversing type hierarchy at the proper non-pointer types,
	// but keep type_id referencing the original pointer for use below.
	uint32_t type_id = expression_type_id(base);

	if (!backend.native_pointers)
	{
		if (ptr_chain)
			SPIRV_CROSS_THROW("Backend does not support native pointers and does not support OpPtrAccessChain.");

		// Wrapped buffer reference pointer types will need to poke into the internal "value" member before
		// continuing the access chain.
		if (should_dereference(base))
		{
			auto &type = get<SPIRType>(type_id);
			expr = dereference_expression(type, expr);
		}
	}

	const auto *type = &get_pointee_type(type_id);

	bool access_chain_is_arrayed = expr.find_first_of('[') != string::npos;
	bool row_major_matrix_needs_conversion = is_non_native_row_major_matrix(base);
	bool is_packed = has_extended_decoration(base, SPIRVCrossDecorationPhysicalTypePacked);
	uint32_t physical_type = get_extended_decoration(base, SPIRVCrossDecorationPhysicalTypeID);
	bool is_invariant = has_decoration(base, DecorationInvariant);
	bool relaxed_precision = has_decoration(base, DecorationRelaxedPrecision);
	bool pending_array_enclose = false;
	bool dimension_flatten = false;
	bool access_meshlet_position_y = false;

	if (auto *base_expr = maybe_get<SPIRExpression>(base))
	{
		access_meshlet_position_y = base_expr->access_meshlet_position_y;
	}

	// If we are translating access to a structured buffer, the first subscript '._m0' must be hidden
	bool hide_first_subscript = count > 1 && is_user_type_structured(base);

	const auto append_index = [&](uint32_t index, bool is_literal, bool is_ptr_chain = false) {
		AccessChainFlags mod_flags = flags;
		if (!is_literal)
			mod_flags &= ~ACCESS_CHAIN_INDEX_IS_LITERAL_BIT;
		if (!is_ptr_chain)
			mod_flags &= ~ACCESS_CHAIN_PTR_CHAIN_BIT;
		access_chain_internal_append_index(expr, base, type, mod_flags, access_chain_is_arrayed, index);
		check_physical_type_cast(expr, type, physical_type);
	};

	for (uint32_t i = 0; i < count; i++)
	{
		uint32_t index = indices[i];

		bool is_literal = index_is_literal;
		if (is_literal && msb_is_id && (index >> 31u) != 0u)
		{
			is_literal = false;
			index &= 0x7fffffffu;
		}

		// Pointer chains
		if (ptr_chain && i == 0)
		{
			// If we are flattening multidimensional arrays, only create opening bracket on first
			// array index.
			if (options.flatten_multidimensional_arrays)
			{
				dimension_flatten = type->array.size() >= 1;
				pending_array_enclose = dimension_flatten;
				if (pending_array_enclose)
					expr += "[";
			}

			if (options.flatten_multidimensional_arrays && dimension_flatten)
			{
				// If we are flattening multidimensional arrays, do manual stride computation.
				if (is_literal)
					expr += convert_to_string(index);
				else
					expr += to_enclosed_expression(index, register_expression_read);

				for (auto j = uint32_t(type->array.size()); j; j--)
				{
					expr += " * ";
					expr += enclose_expression(to_array_size(*type, j - 1));
				}

				if (type->array.empty())
					pending_array_enclose = false;
				else
					expr += " + ";

				if (!pending_array_enclose)
					expr += "]";
			}
			else
			{
				append_index(index, is_literal, true);
			}

			if (type->basetype == SPIRType::ControlPointArray)
			{
				type_id = type->parent_type;
				type = &get<SPIRType>(type_id);
			}

			access_chain_is_arrayed = true;
		}
		// Arrays
		else if (!type->array.empty())
		{
			// If we are flattening multidimensional arrays, only create opening bracket on first
			// array index.
			if (options.flatten_multidimensional_arrays && !pending_array_enclose)
			{
				dimension_flatten = type->array.size() > 1;
				pending_array_enclose = dimension_flatten;
				if (pending_array_enclose)
					expr += "[";
			}

			assert(type->parent_type);

			auto *var = maybe_get<SPIRVariable>(base);
			if (backend.force_gl_in_out_block && i == 0 && var && is_builtin_variable(*var) &&
			    !has_decoration(type->self, DecorationBlock))
			{
				// This deals with scenarios for tesc/geom where arrays of gl_Position[] are declared.
				// Normally, these variables live in blocks when compiled from GLSL,
				// but HLSL seems to just emit straight arrays here.
				// We must pretend this access goes through gl_in/gl_out arrays
				// to be able to access certain builtins as arrays.
				// Similar concerns apply for mesh shaders where we have to redirect to gl_MeshVerticesEXT or MeshPrimitivesEXT.
				auto builtin = ir.meta[base].decoration.builtin_type;
				bool mesh_shader = get_execution_model() == ExecutionModelMeshEXT;

				switch (builtin)
				{
				case BuiltInCullDistance:
				case BuiltInClipDistance:
					if (type->array.size() == 1) // Red herring. Only consider block IO for two-dimensional arrays here.
					{
						append_index(index, is_literal);
						break;
					}
					// fallthrough
				case BuiltInPosition:
				case BuiltInPointSize:
					if (mesh_shader)
						expr = join("gl_MeshVerticesEXT[", to_expression(index, register_expression_read), "].", expr);
					else if (var->storage == StorageClassInput)
						expr = join("gl_in[", to_expression(index, register_expression_read), "].", expr);
					else if (var->storage == StorageClassOutput)
						expr = join("gl_out[", to_expression(index, register_expression_read), "].", expr);
					else
						append_index(index, is_literal);
					break;

				case BuiltInPrimitiveId:
				case BuiltInLayer:
				case BuiltInViewportIndex:
				case BuiltInCullPrimitiveEXT:
				case BuiltInPrimitiveShadingRateKHR:
					if (mesh_shader)
						expr = join("gl_MeshPrimitivesEXT[", to_expression(index, register_expression_read), "].", expr);
					else
						append_index(index, is_literal);
					break;

				default:
					append_index(index, is_literal);
					break;
				}
			}
			else if (backend.force_merged_mesh_block && i == 0 && var &&
			         !is_builtin_variable(*var) && var->storage == StorageClassOutput)
			{
				if (is_per_primitive_variable(*var))
					expr = join("gl_MeshPrimitivesEXT[", to_expression(index, register_expression_read), "].", expr);
				else
					expr = join("gl_MeshVerticesEXT[", to_expression(index, register_expression_read), "].", expr);
			}
			else if (options.flatten_multidimensional_arrays && dimension_flatten)
			{
				// If we are flattening multidimensional arrays, do manual stride computation.
				auto &parent_type = get<SPIRType>(type->parent_type);

				if (is_literal)
					expr += convert_to_string(index);
				else
					expr += to_enclosed_expression(index, register_expression_read);

				for (auto j = uint32_t(parent_type.array.size()); j; j--)
				{
					expr += " * ";
					expr += enclose_expression(to_array_size(parent_type, j - 1));
				}

				if (parent_type.array.empty())
					pending_array_enclose = false;
				else
					expr += " + ";

				if (!pending_array_enclose)
					expr += "]";
			}
			// Some builtins are arrays in SPIR-V but not in other languages, e.g. gl_SampleMask[] is an array in SPIR-V but not in Metal.
			// By throwing away the index, we imply the index was 0, which it must be for gl_SampleMask.
			else if (!builtin_translates_to_nonarray(BuiltIn(get_decoration(base, DecorationBuiltIn))))
			{
				append_index(index, is_literal);
			}

			if (var && has_decoration(var->self, DecorationBuiltIn) &&
			    get_decoration(var->self, DecorationBuiltIn) == BuiltInPosition &&
			    get_execution_model() == ExecutionModelMeshEXT)
			{
				access_meshlet_position_y = true;
			}

			type_id = type->parent_type;
			type = &get<SPIRType>(type_id);

			access_chain_is_arrayed = true;
		}
		// For structs, the index refers to a constant, which indexes into the members, possibly through a redirection mapping.
		// We also check if this member is a builtin, since we then replace the entire expression with the builtin one.
		else if (type->basetype == SPIRType::Struct)
		{
			if (!is_literal)
				index = evaluate_constant_u32(index);

			if (index < uint32_t(type->member_type_index_redirection.size()))
				index = type->member_type_index_redirection[index];

			if (index >= type->member_types.size())
				SPIRV_CROSS_THROW("Member index is out of bounds!");

			if (hide_first_subscript)
			{
				// First "._m0" subscript has been hidden, subsequent fields must be emitted even for structured buffers
				hide_first_subscript = false;
			}
			else
			{
				BuiltIn builtin = BuiltInMax;
				if (is_member_builtin(*type, index, &builtin) && access_chain_needs_stage_io_builtin_translation(base))
				{
					if (access_chain_is_arrayed)
					{
						expr += ".";
						expr += builtin_to_glsl(builtin, type->storage);
					}
					else
						expr = builtin_to_glsl(builtin, type->storage);

					if (builtin == BuiltInPosition && get_execution_model() == ExecutionModelMeshEXT)
					{
						access_meshlet_position_y = true;
					}
				}
				else
				{
					// If the member has a qualified name, use it as the entire chain
					string qual_mbr_name = get_member_qualified_name(type_id, index);
					if (!qual_mbr_name.empty())
						expr = qual_mbr_name;
					else if (flatten_member_reference)
						expr += join("_", to_member_name(*type, index));
					else
					{
						// Any pointer de-refences for values are handled in the first access chain.
						// For pointer chains, the pointer-ness is resolved through an array access.
						// The only time this is not true is when accessing array of SSBO/UBO.
						// This case is explicitly handled.
						expr += to_member_reference(base, *type, index, ptr_chain || i != 0);
					}
				}
			}

			if (has_member_decoration(type->self, index, DecorationInvariant))
				is_invariant = true;
			if (has_member_decoration(type->self, index, DecorationRelaxedPrecision))
				relaxed_precision = true;

			is_packed = member_is_packed_physical_type(*type, index);
			if (member_is_remapped_physical_type(*type, index))
				physical_type = get_extended_member_decoration(type->self, index, SPIRVCrossDecorationPhysicalTypeID);
			else
				physical_type = 0;

			row_major_matrix_needs_conversion = member_is_non_native_row_major_matrix(*type, index);
			type = &get<SPIRType>(type->member_types[index]);
		}
		// Matrix -> Vector
		else if (type->columns > 1)
		{
			// If we have a row-major matrix here, we need to defer any transpose in case this access chain
			// is used to store a column. We can resolve it right here and now if we access a scalar directly,
			// by flipping indexing order of the matrix.

			expr += "[";
			if (is_literal)
				expr += convert_to_string(index);
			else
				expr += to_unpacked_expression(index, register_expression_read);
			expr += "]";

			type_id = type->parent_type;
			type = &get<SPIRType>(type_id);
		}
		// Vector -> Scalar
		else if (type->vecsize > 1)
		{
			string deferred_index;
			if (row_major_matrix_needs_conversion)
			{
				// Flip indexing order.
				auto column_index = expr.find_last_of('[');
				if (column_index != string::npos)
				{
					deferred_index = expr.substr(column_index);
					expr.resize(column_index);
				}
			}

			// Internally, access chain implementation can also be used on composites,
			// ignore scalar access workarounds in this case.
			StorageClass effective_storage = StorageClassGeneric;
			bool ignore_potential_sliced_writes = false;
			if ((flags & ACCESS_CHAIN_FORCE_COMPOSITE_BIT) == 0)
			{
				if (expression_type(base).pointer)
					effective_storage = get_expression_effective_storage_class(base);

				// Special consideration for control points.
				// Control points can only be written by InvocationID, so there is no need
				// to consider scalar access chains here.
				// Cleans up some cases where it's very painful to determine the accurate storage class
				// since blocks can be partially masked ...
				auto *var = maybe_get_backing_variable(base);
				if (var && var->storage == StorageClassOutput &&
				    get_execution_model() == ExecutionModelTessellationControl &&
				    !has_decoration(var->self, DecorationPatch))
				{
					ignore_potential_sliced_writes = true;
				}
			}
			else
				ignore_potential_sliced_writes = true;

			if (!row_major_matrix_needs_conversion && !ignore_potential_sliced_writes)
			{
				// On some backends, we might not be able to safely access individual scalars in a vector.
				// To work around this, we might have to cast the access chain reference to something which can,
				// like a pointer to scalar, which we can then index into.
				prepare_access_chain_for_scalar_access(expr, get<SPIRType>(type->parent_type), effective_storage,
				                                       is_packed);
			}

			if (is_literal)
			{
				bool out_of_bounds = (index >= type->vecsize);

				if (!is_packed && !row_major_matrix_needs_conversion)
				{
					expr += ".";
					expr += index_to_swizzle(out_of_bounds ? 0 : index);
				}
				else
				{
					// For packed vectors, we can only access them as an array, not by swizzle.
					expr += join("[", out_of_bounds ? 0 : index, "]");
				}
			}
			else if (ir.ids[index].get_type() == TypeConstant && !is_packed && !row_major_matrix_needs_conversion)
			{
				auto &c = get<SPIRConstant>(index);
				bool out_of_bounds = (c.scalar() >= type->vecsize);

				if (c.specialization)
				{
					// If the index is a spec constant, we cannot turn extract into a swizzle.
					expr += join("[", out_of_bounds ? "0" : to_expression(index), "]");
				}
				else
				{
					expr += ".";
					expr += index_to_swizzle(out_of_bounds ? 0 : c.scalar());
				}
			}
			else
			{
				expr += "[";
				expr += to_unpacked_expression(index, register_expression_read);
				expr += "]";
			}

			if (row_major_matrix_needs_conversion && !ignore_potential_sliced_writes)
			{
				prepare_access_chain_for_scalar_access(expr, get<SPIRType>(type->parent_type), effective_storage,
				                                       is_packed);
			}

			if (access_meshlet_position_y)
			{
				if (is_literal)
				{
					access_meshlet_position_y = index == 1;
				}
				else
				{
					const auto *c = maybe_get<SPIRConstant>(index);
					if (c)
						access_meshlet_position_y = c->scalar() == 1;
					else
					{
						// We don't know, but we have to assume no.
						// Flip Y in mesh shaders is an opt-in horrible hack, so we'll have to assume shaders try to behave.
						access_meshlet_position_y = false;
					}
				}
			}

			expr += deferred_index;
			row_major_matrix_needs_conversion = false;

			is_packed = false;
			physical_type = 0;
			type_id = type->parent_type;
			type = &get<SPIRType>(type_id);
		}
		else if (!backend.allow_truncated_access_chain)
			SPIRV_CROSS_THROW("Cannot subdivide a scalar value!");
	}

	if (pending_array_enclose)
	{
		SPIRV_CROSS_THROW("Flattening of multidimensional arrays were enabled, "
		                  "but the access chain was terminated in the middle of a multidimensional array. "
		                  "This is not supported.");
	}

	if (meta)
	{
		meta->need_transpose = row_major_matrix_needs_conversion;
		meta->storage_is_packed = is_packed;
		meta->storage_is_invariant = is_invariant;
		meta->storage_physical_type = physical_type;
		meta->relaxed_precision = relaxed_precision;
		meta->access_meshlet_position_y = access_meshlet_position_y;
	}

	return expr;
}

const char *CompilerHLSL::index_to_swizzle(uint32_t index)
{
	switch (index)
	{
	case 0:
		return "x";
	case 1:
		return "y";
	case 2:
		return "z";
	case 3:
		return "w";
	default:
		return "x";		// Don't crash, but engage the "undefined behavior" described for out-of-bounds logical addressing in spec.
	}
}

bool CompilerHLSL::remove_duplicate_swizzle(string &op)
{
	auto pos = op.find_last_of('.');
	if (pos == string::npos || pos == 0)
		return false;

	string final_swiz = op.substr(pos + 1, string::npos);

	if (backend.swizzle_is_function)
	{
		if (final_swiz.size() < 2)
			return false;

		if (final_swiz.substr(final_swiz.size() - 2, string::npos) == "()")
			final_swiz.erase(final_swiz.size() - 2, string::npos);
		else
			return false;
	}

	// Check if final swizzle is of form .x, .xy, .xyz, .xyzw or similar.
	// If so, and previous swizzle is of same length,
	// we can drop the final swizzle altogether.
	for (uint32_t i = 0; i < final_swiz.size(); i++)
	{
		static const char expected[] = { 'x', 'y', 'z', 'w' };
		if (i >= 4 || final_swiz[i] != expected[i])
			return false;
	}

	auto prevpos = op.find_last_of('.', pos - 1);
	if (prevpos == string::npos)
		return false;

	prevpos++;

	// Make sure there are only swizzles here ...
	for (auto i = prevpos; i < pos; i++)
	{
		if (op[i] < 'w' || op[i] > 'z')
		{
			// If swizzles are foo.xyz() like in C++ backend for example, check for that.
			if (backend.swizzle_is_function && i + 2 == pos && op[i] == '(' && op[i + 1] == ')')
				break;
			return false;
		}
	}

	// If original swizzle is large enough, just carve out the components we need.
	// E.g. foobar.wyx.xy will turn into foobar.wy.
	if (pos - prevpos >= final_swiz.size())
	{
		op.erase(prevpos + final_swiz.size(), string::npos);

		// Add back the function call ...
		if (backend.swizzle_is_function)
			op += "()";
	}
	return true;
}

string CompilerHLSL::to_dereferenced_expression(uint32_t id, bool register_expression_read)
{
	auto &type = expression_type(id);
	if (type.pointer && should_dereference(id))
		return dereference_expression(type, to_enclosed_expression(id, register_expression_read));
	else
		return to_expression(id, register_expression_read);
}

string CompilerHLSL::access_chain(uint32_t base, const uint32_t *indices, uint32_t count, const SPIRType &target_type,
                                  AccessChainMeta *meta, bool ptr_chain)
{
	if (flattened_buffer_blocks.count(base))
	{
		uint32_t matrix_stride = 0;
		uint32_t array_stride = 0;
		bool need_transpose = false;
		flattened_access_chain_offset(expression_type(base), indices, count, 0, 16, &need_transpose, &matrix_stride,
		                              &array_stride, ptr_chain);

		if (meta)
		{
			meta->need_transpose = target_type.columns > 1 && need_transpose;
			meta->storage_is_packed = false;
		}

		return flattened_access_chain(base, indices, count, target_type, 0, matrix_stride, array_stride,
		                              need_transpose);
	}
	else if (flattened_structs.count(base) && count > 0)
	{
		AccessChainFlags flags = ACCESS_CHAIN_CHAIN_ONLY_BIT | ACCESS_CHAIN_SKIP_REGISTER_EXPRESSION_READ_BIT;
		if (ptr_chain)
			flags |= ACCESS_CHAIN_PTR_CHAIN_BIT;

		if (flattened_structs[base])
		{
			flags |= ACCESS_CHAIN_FLATTEN_ALL_MEMBERS_BIT;
			if (meta)
				meta->flattened_struct = target_type.basetype == SPIRType::Struct;
		}

		auto chain = access_chain_internal(base, indices, count, flags, nullptr).substr(1);
		if (meta)
		{
			meta->need_transpose = false;
			meta->storage_is_packed = false;
		}

		auto basename = to_flattened_access_chain_expression(base);
		auto ret = join(basename, "_", chain);
		ParsedIR::sanitize_underscores(ret);
		return ret;
	}
	else
	{
		AccessChainFlags flags = ACCESS_CHAIN_SKIP_REGISTER_EXPRESSION_READ_BIT;
		if (ptr_chain)
			flags |= ACCESS_CHAIN_PTR_CHAIN_BIT;
		return access_chain_internal(base, indices, count, flags, meta);
	}
}

uint32_t CompilerHLSL::get_integer_width_for_instruction(const Instruction &instr) const
{
	if (instr.length < 3)
		return 32;

	auto *ops = stream(instr);

	switch (instr.op)
	{
	case OpSConvert:
	case OpConvertSToF:
	case OpUConvert:
	case OpConvertUToF:
	case OpIEqual:
	case OpINotEqual:
	case OpSLessThan:
	case OpSLessThanEqual:
	case OpSGreaterThan:
	case OpSGreaterThanEqual:
	case OpULessThan:
	case OpULessThanEqual:
	case OpUGreaterThan:
	case OpUGreaterThanEqual:
		return expression_type(ops[2]).width;

	default:
	{
		// We can look at result type which is more robust.
		auto *type = maybe_get<SPIRType>(ops[0]);
		if (type && type_is_integral(*type))
			return type->width;
		else
			return 32;
	}
	}
}

Op CompilerHLSL::get_remapped_spirv_op(Op op) const
{
	if (options.relax_nan_checks)
	{
		switch (op)
		{
		case OpFUnordLessThan:
			op = OpFOrdLessThan;
			break;
		case OpFUnordLessThanEqual:
			op = OpFOrdLessThanEqual;
			break;
		case OpFUnordGreaterThan:
			op = OpFOrdGreaterThan;
			break;
		case OpFUnordGreaterThanEqual:
			op = OpFOrdGreaterThanEqual;
			break;
		case OpFUnordEqual:
			op = OpFOrdEqual;
			break;
		case OpFOrdNotEqual:
			op = OpFUnordNotEqual;
			break;

		default:
			break;
		}
	}

	return op;
}

string CompilerHLSL::type_to_glsl_constructor(const SPIRType &type)
{
	if (backend.use_array_constructor && type.array.size() > 1)
	{
		if (options.flatten_multidimensional_arrays)
			SPIRV_CROSS_THROW("Cannot flatten constructors of multidimensional array constructors, "
			                  "e.g. float[][]().");
		else if (!options.es && options.version < 430)
			require_extension_internal("GL_ARB_arrays_of_arrays");
		else if (options.es && options.version < 310)
			SPIRV_CROSS_THROW("Arrays of arrays not supported before ESSL version 310.");
	}

	auto e = type_to_glsl(type);
	if (backend.use_array_constructor)
	{
		for (uint32_t i = 0; i < type.array.size(); i++)
			e += "[]";
	}
	return e;
}

void CompilerHLSL::emit_unary_op(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op)
{
	bool forward = should_forward(op0);
	emit_op(result_type, result_id, join(op, to_enclosed_unpacked_expression(op0)), forward);
	inherit_expression_dependencies(result_id, op0);
}

void CompilerHLSL::emit_binary_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                       const char *op, SPIRType::BaseType input_type,
                                       bool skip_cast_if_equal_type,
                                       bool implicit_integer_promotion)
{
	string cast_op0, cast_op1;
	auto expected_type = binary_op_bitcast_helper(cast_op0, cast_op1, input_type, op0, op1, skip_cast_if_equal_type);
	auto &out_type = get<SPIRType>(result_type);

	// We might have casted away from the result type, so bitcast again.
	// For example, arithmetic right shift with uint inputs.
	// Special case boolean outputs since relational opcodes output booleans instead of int/uint.
	auto bitop = join(cast_op0, " ", op, " ", cast_op1);
	string expr;

	if (implicit_integer_promotion)
	{
		// Simple value cast.
		expr = join(type_to_glsl(out_type), '(', bitop, ')');
	}
	else if (out_type.basetype != input_type && out_type.basetype != SPIRType::Boolean)
	{
		expected_type.basetype = input_type;
		expr = join(bitcast_glsl_op(out_type, expected_type), '(', bitop, ')');
	}
	else
	{
		expr = std::move(bitop);
	}

	emit_op(result_type, result_id, expr, should_forward(op0) && should_forward(op1));
	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
}

void CompilerHLSL::emit_binary_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1, const char *op)
{
	// Various FP arithmetic opcodes such as add, sub, mul will hit this.
	bool force_temporary_precise = backend.support_precise_qualifier &&
	                               has_decoration(result_id, DecorationNoContraction) &&
	                               type_is_floating_point(get<SPIRType>(result_type));
	bool forward = should_forward(op0) && should_forward(op1) && !force_temporary_precise;

	emit_op(result_type, result_id,
	        join(to_enclosed_unpacked_expression(op0), " ", op, " ", to_enclosed_unpacked_expression(op1)), forward);

	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
}

string CompilerHLSL::remap_swizzle(const SPIRType &out_type, uint32_t input_components, const string &expr)
{
	if (out_type.vecsize == input_components)
		return expr;
	else if (input_components == 1 && !backend.can_swizzle_scalar)
		return join(type_to_glsl(out_type), "(", expr, ")");
	else
	{
		// FIXME: This will not work with packed expressions.
		auto e = enclose_expression(expr) + ".";
		// Just clamp the swizzle index if we have more outputs than inputs.
		for (uint32_t c = 0; c < out_type.vecsize; c++)
			e += index_to_swizzle(min(c, input_components - 1));
		if (backend.swizzle_is_function && out_type.vecsize > 1)
			e += "()";

		remove_duplicate_swizzle(e);
		return e;
	}
}

void CompilerHLSL::fixup_anonymous_struct_names()
{
	// HLSL codegen can often end up emitting anonymous structs inside blocks, which
	// breaks GL linking since all names must match ...
	// Try to emit sensible code, so attempt to find such structs and emit anon_$member.

	// Breaks exponential explosion with weird type trees.
	std::unordered_set<uint32_t> visited;

	ir.for_each_typed_id<SPIRType>([&](uint32_t, SPIRType &type) {
		if (type.basetype == SPIRType::Struct &&
		    (has_decoration(type.self, DecorationBlock) ||
		     has_decoration(type.self, DecorationBufferBlock)))
		{
			fixup_anonymous_struct_names(visited, type);
		}
	});
}

void CompilerHLSL::fixup_anonymous_struct_names(std::unordered_set<uint32_t> &visited, const SPIRType &type)
{
	if (visited.count(type.self))
		return;
	visited.insert(type.self);

	for (uint32_t i = 0; i < uint32_t(type.member_types.size()); i++)
	{
		auto &mbr_type = get<SPIRType>(type.member_types[i]);

		if (mbr_type.basetype == SPIRType::Struct)
		{
			// If there are multiple aliases, the output might be somewhat unpredictable,
			// but the only real alternative in that case is to do nothing, which isn't any better.
			// This check should be fine in practice.
			if (get_name(mbr_type.self).empty() && !get_member_name(type.self, i).empty())
			{
				auto anon_name = join("anon_", get_member_name(type.self, i));
				ParsedIR::sanitize_underscores(anon_name);
				set_name(mbr_type.self, anon_name);
			}

			fixup_anonymous_struct_names(visited, mbr_type);
		}
	}
}

void CompilerHLSL::fixup_type_alias()
{
	// Due to how some backends work, the "master" type of type_alias must be a block-like type if it exists.
	ir.for_each_typed_id<SPIRType>([&](uint32_t self, SPIRType &type) {
		if (!type.type_alias)
			return;

		if (has_decoration(type.self, DecorationBlock) || has_decoration(type.self, DecorationBufferBlock))
		{
			// Top-level block types should never alias anything else.
			type.type_alias = 0;
		}
		else if (type_is_block_like(type) && type.self == ID(self))
		{
			// A block-like type is any type which contains Offset decoration, but not top-level blocks,
			// i.e. blocks which are placed inside buffers.
			// Become the master.
			ir.for_each_typed_id<SPIRType>([&](uint32_t other_id, SPIRType &other_type) {
				if (other_id == self)
					return;

				if (other_type.type_alias == type.type_alias)
					other_type.type_alias = self;
			});

			this->get<SPIRType>(type.type_alias).type_alias = self;
			type.type_alias = 0;
		}
	});
}

void CompilerHLSL::reorder_type_alias()
{
	// Reorder declaration of types so that the master of the type alias is always emitted first.
	// We need this in case a type B depends on type A (A must come before in the vector), but A is an alias of a type Abuffer, which
	// means declaration of A doesn't happen (yet), and order would be B, ABuffer and not ABuffer, B. Fix this up here.
	auto loop_lock = ir.create_loop_hard_lock();

	auto &type_ids = ir.ids_for_type[TypeType];
	for (auto alias_itr = begin(type_ids); alias_itr != end(type_ids); ++alias_itr)
	{
		auto &type = get<SPIRType>(*alias_itr);
		if (type.type_alias != TypeID(0) &&
		    !has_extended_decoration(type.type_alias, SPIRVCrossDecorationBufferBlockRepacked))
		{
			// We will skip declaring this type, so make sure the type_alias type comes before.
			auto master_itr = find(begin(type_ids), end(type_ids), ID(type.type_alias));
			assert(master_itr != end(type_ids));

			if (alias_itr < master_itr)
			{
				// Must also swap the type order for the constant-type joined array.
				auto &joined_types = ir.ids_for_constant_undef_or_type;
				auto alt_alias_itr = find(begin(joined_types), end(joined_types), *alias_itr);
				auto alt_master_itr = find(begin(joined_types), end(joined_types), *master_itr);
				assert(alt_alias_itr != end(joined_types));
				assert(alt_master_itr != end(joined_types));

				swap(*alias_itr, *master_itr);
				swap(*alt_alias_itr, *alt_master_itr);
			}
		}
	}
}

void CompilerHLSL::reset(uint32_t iteration_count)
{
	// Sanity check the iteration count to be robust against a certain class of bugs where
	// we keep forcing recompilations without making clear forward progress.
	// In buggy situations we will loop forever, or loop for an unbounded number of iterations.
	// Certain types of recompilations are considered to make forward progress,
	// but in almost all situations, we'll never see more than 3 iterations.
	// It is highly context-sensitive when we need to force recompilation,
	// and it is not practical with the current architecture
	// to resolve everything up front.
	if (iteration_count >= options.force_recompile_max_debug_iterations && !is_force_recompile_forward_progress)
		SPIRV_CROSS_THROW("Maximum compilation loops detected and no forward progress was made. Must be a SPIRV-Cross bug!");

	// We do some speculative optimizations which should pretty much always work out,
	// but just in case the SPIR-V is rather weird, recompile until it's happy.
	// This typically only means one extra pass.
	clear_force_recompile();

	// Clear invalid expression tracking.
	invalid_expressions.clear();
	composite_insert_overwritten.clear();
	current_function = nullptr;

	// Clear temporary usage tracking.
	expression_usage_counts.clear();
	forwarded_temporaries.clear();
	suppressed_usage_tracking.clear();

	// Ensure that we declare phi-variable copies even if the original declaration isn't deferred
	flushed_phi_variables.clear();

	current_emitting_switch_stack.clear();

	reset_name_caches();

	ir.for_each_typed_id<SPIRFunction>([&](uint32_t, SPIRFunction &func) {
		func.active = false;
		func.flush_undeclared = true;
	});

	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) { var.dependees.clear(); });

	ir.reset_all_of_type<SPIRExpression>();
	ir.reset_all_of_type<SPIRAccessChain>();

	statement_count = 0;
	indent = 0;
	current_loop_level = 0;
}

void CompilerHLSL::reset_name_caches()
{
	for (auto &preserved : preserved_aliases)
		set_name(preserved.first, preserved.second);

	preserved_aliases.clear();
	resource_names.clear();
	block_input_names.clear();
	block_output_names.clear();
	block_ubo_names.clear();
	block_ssbo_names.clear();
	block_names.clear();
	function_overloads.clear();
}

void CompilerHLSL::emit_function(SPIRFunction &func, const Bitset &return_flags)
{
	// Avoid potential cycles.
	if (func.active)
		return;
	func.active = true;

	// If we depend on a function, emit that function before we emit our own function.
	for (auto block : func.blocks)
	{
		auto &b = get<SPIRBlock>(block);
		for (auto &i : b.ops)
		{
			auto ops = stream(i);
			auto op = static_cast<Op>(i.op);

			if (op == OpFunctionCall)
			{
				// Recursively emit functions which are called.
				uint32_t id = ops[2];
				emit_function(get<SPIRFunction>(id), ir.meta[ops[1]].decoration.decoration_flags);
			}
		}
	}

	if (func.entry_line.file_id != 0)
		emit_line_directive(func.entry_line.file_id, func.entry_line.line_literal);
	emit_function_prototype(func, return_flags);
	begin_scope();

	if (func.self == ir.default_entry_point)
		emit_entry_point_declarations();

	current_function = &func;
	auto &entry_block = get<SPIRBlock>(func.entry_block);

	sort(begin(func.constant_arrays_needed_on_stack), end(func.constant_arrays_needed_on_stack));
	for (auto &array : func.constant_arrays_needed_on_stack)
	{
		auto &c = get<SPIRConstant>(array);
		auto &type = get<SPIRType>(c.constant_type);
		statement(variable_decl(type, join("_", array, "_array_copy")), " = ", constant_expression(c), ";");
	}

	for (auto &v : func.local_variables)
	{
		auto &var = get<SPIRVariable>(v);
		var.deferred_declaration = false;

		if (variable_decl_is_remapped_storage(var, StorageClassWorkgroup))
		{
			// Special variable type which cannot have initializer,
			// need to be declared as standalone variables.
			// Comes from MSL which can push global variables as local variables in main function.
			add_local_variable_name(var.self);
			statement(variable_decl(var), ";");
			var.deferred_declaration = false;
		}
		else if (var.storage == StorageClassPrivate)
		{
			// These variables will not have had their CFG usage analyzed, so move it to the entry block.
			// Comes from MSL which can push global variables as local variables in main function.
			// We could just declare them right now, but we would miss out on an important initialization case which is
			// LUT declaration in MSL.
			// If we don't declare the variable when it is assigned we're forced to go through a helper function
			// which copies elements one by one.
			add_local_variable_name(var.self);

			if (var.initializer)
			{
				statement(variable_decl(var), ";");
				var.deferred_declaration = false;
			}
			else
			{
				auto &dominated = entry_block.dominated_variables;
				if (find(begin(dominated), end(dominated), var.self) == end(dominated))
					entry_block.dominated_variables.push_back(var.self);
				var.deferred_declaration = true;
			}
		}
		else if (var.storage == StorageClassFunction && var.remapped_variable && var.static_expression)
		{
			// No need to declare this variable, it has a static expression.
			var.deferred_declaration = false;
		}
		else if (expression_is_lvalue(v))
		{
			add_local_variable_name(var.self);

			// Loop variables should never be declared early, they are explicitly emitted in a loop.
			if (var.initializer && !var.loop_variable)
				statement(variable_decl_function_local(var), ";");
			else
			{
				// Don't declare variable until first use to declutter the GLSL output quite a lot.
				// If we don't touch the variable before first branch,
				// declare it then since we need variable declaration to be in top scope.
				var.deferred_declaration = true;
			}
		}
		else
		{
			// HACK: SPIR-V in older glslang output likes to use samplers and images as local variables, but GLSL does not allow this.
			// For these types (non-lvalue), we enforce forwarding through a shadowed variable.
			// This means that when we OpStore to these variables, we just write in the expression ID directly.
			// This breaks any kind of branching, since the variable must be statically assigned.
			// Branching on samplers and images would be pretty much impossible to fake in GLSL.
			var.statically_assigned = true;
		}

		var.loop_variable_enable = false;

		// Loop variables are never declared outside their for-loop, so block any implicit declaration.
		if (var.loop_variable)
		{
			var.deferred_declaration = false;
			// Need to reset the static expression so we can fallback to initializer if need be.
			var.static_expression = 0;
		}
	}

	// Enforce declaration order for regression testing purposes.
	for (auto &block_id : func.blocks)
	{
		auto &block = get<SPIRBlock>(block_id);
		sort(begin(block.dominated_variables), end(block.dominated_variables));
	}

	for (auto &line : current_function->fixup_hooks_in)
		line();

	emit_block_chain(entry_block);

	end_scope();
	processing_entry_point = false;
	statement("");

	// Make sure deferred declaration state for local variables is cleared when we are done with function.
	// We risk declaring Private/Workgroup variables in places we are not supposed to otherwise.
	for (auto &v : func.local_variables)
	{
		auto &var = get<SPIRVariable>(v);
		var.deferred_declaration = false;
	}
}

void CompilerHLSL::emit_entry_point_declarations()
{
}

void CompilerHLSL::emit_block_chain(SPIRBlock &block)
{
	bool select_branch_to_true_block = false;
	bool select_branch_to_false_block = false;
	bool skip_direct_branch = false;
	bool emitted_loop_header_variables = false;
	bool force_complex_continue_block = false;
	ValueSaver<uint32_t> loop_level_saver(current_loop_level);

	if (block.merge == SPIRBlock::MergeLoop)
		add_loop_level();

	// If we're emitting PHI variables with precision aliases, we have to emit them as hoisted temporaries.
	for (auto var_id : block.dominated_variables)
	{
		auto &var = get<SPIRVariable>(var_id);
		if (var.phi_variable)
		{
			auto mirrored_precision_itr = temporary_to_mirror_precision_alias.find(var_id);
			if (mirrored_precision_itr != temporary_to_mirror_precision_alias.end() &&
			    find_if(block.declare_temporary.begin(), block.declare_temporary.end(),
			            [mirrored_precision_itr](const std::pair<TypeID, VariableID> &p) {
			              return p.second == mirrored_precision_itr->second;
			            }) == block.declare_temporary.end())
			{
				block.declare_temporary.push_back({ var.basetype, mirrored_precision_itr->second });
			}
		}
	}

	emit_hoisted_temporaries(block.declare_temporary);

	SPIRBlock::ContinueBlockType continue_type = SPIRBlock::ContinueNone;
	if (block.continue_block)
	{
		continue_type = continue_block_type(get<SPIRBlock>(block.continue_block));
		// If we know we cannot emit a loop, mark the block early as a complex loop so we don't force unnecessary recompiles.
		if (continue_type == SPIRBlock::ComplexLoop)
			block.complex_continue = true;
	}

	// If we have loop variables, stop masking out access to the variable now.
	for (auto var_id : block.loop_variables)
	{
		auto &var = get<SPIRVariable>(var_id);
		var.loop_variable_enable = true;
		// We're not going to declare the variable directly, so emit a copy here.
		emit_variable_temporary_copies(var);
	}

	// Remember deferred declaration state. We will restore it before returning.
	SmallVector<bool, 64> rearm_dominated_variables(block.dominated_variables.size());
	for (size_t i = 0; i < block.dominated_variables.size(); i++)
	{
		uint32_t var_id = block.dominated_variables[i];
		auto &var = get<SPIRVariable>(var_id);
		rearm_dominated_variables[i] = var.deferred_declaration;
	}

	// This is the method often used by spirv-opt to implement loops.
	// The loop header goes straight into the continue block.
	// However, don't attempt this on ESSL 1.0, because if a loop variable is used in a continue block,
	// it *MUST* be used in the continue block. This loop method will not work.
	if (!is_legacy_es() && block_is_loop_candidate(block, SPIRBlock::MergeToSelectContinueForLoop))
	{
		flush_undeclared_variables(block);
		if (attempt_emit_loop_header(block, SPIRBlock::MergeToSelectContinueForLoop))
		{
			if (execution_is_noop(get<SPIRBlock>(block.true_block), get<SPIRBlock>(block.merge_block)))
				select_branch_to_false_block = true;
			else
				select_branch_to_true_block = true;

			emitted_loop_header_variables = true;
			force_complex_continue_block = true;
		}
	}
	// This is the older loop behavior in glslang which branches to loop body directly from the loop header.
	else if (block_is_loop_candidate(block, SPIRBlock::MergeToSelectForLoop))
	{
		flush_undeclared_variables(block);
		if (attempt_emit_loop_header(block, SPIRBlock::MergeToSelectForLoop))
		{
			// The body of while, is actually just the true (or false) block, so always branch there unconditionally.
			if (execution_is_noop(get<SPIRBlock>(block.true_block), get<SPIRBlock>(block.merge_block)))
				select_branch_to_false_block = true;
			else
				select_branch_to_true_block = true;

			emitted_loop_header_variables = true;
		}
	}
	// This is the newer loop behavior in glslang which branches from Loop header directly to
	// a new block, which in turn has a OpBranchSelection without a selection merge.
	else if (block_is_loop_candidate(block, SPIRBlock::MergeToDirectForLoop))
	{
		flush_undeclared_variables(block);
		if (attempt_emit_loop_header(block, SPIRBlock::MergeToDirectForLoop))
		{
			skip_direct_branch = true;
			emitted_loop_header_variables = true;
		}
	}
	else if (continue_type == SPIRBlock::DoWhileLoop)
	{
		flush_undeclared_variables(block);
		emit_while_loop_initializers(block);
		emitted_loop_header_variables = true;
		// We have some temporaries where the loop header is the dominator.
		// We risk a case where we have code like:
		// for (;;) { create-temporary; break; } consume-temporary;
		// so force-declare temporaries here.
		emit_hoisted_temporaries(block.potential_declare_temporary);
		statement("do");
		begin_scope();

		emit_block_instructions(block);
	}
	else if (block.merge == SPIRBlock::MergeLoop)
	{
		flush_undeclared_variables(block);
		emit_while_loop_initializers(block);
		emitted_loop_header_variables = true;

		// We have a generic loop without any distinguishable pattern like for, while or do while.
		get<SPIRBlock>(block.continue_block).complex_continue = true;
		continue_type = SPIRBlock::ComplexLoop;

		// We have some temporaries where the loop header is the dominator.
		// We risk a case where we have code like:
		// for (;;) { create-temporary; break; } consume-temporary;
		// so force-declare temporaries here.
		emit_hoisted_temporaries(block.potential_declare_temporary);
		emit_block_hints(block);
		statement("for (;;)");
		begin_scope();

		emit_block_instructions(block);
	}
	else
	{
		emit_block_instructions(block);
	}

	// If we didn't successfully emit a loop header and we had loop variable candidates, we have a problem
	// as writes to said loop variables might have been masked out, we need a recompile.
	if (!emitted_loop_header_variables && !block.loop_variables.empty())
	{
		force_recompile_guarantee_forward_progress();
		for (auto var : block.loop_variables)
			get<SPIRVariable>(var).loop_variable = false;
		block.loop_variables.clear();
	}

	flush_undeclared_variables(block);
	bool emit_next_block = true;

	// Handle end of block.
	switch (block.terminator)
	{
	case SPIRBlock::Direct:
		// True when emitting complex continue block.
		if (block.loop_dominator == block.next_block)
		{
			branch(block.self, block.next_block);
			emit_next_block = false;
		}
		// True if MergeToDirectForLoop succeeded.
		else if (skip_direct_branch)
			emit_next_block = false;
		else if (is_continue(block.next_block) || is_break(block.next_block) || is_conditional(block.next_block))
		{
			branch(block.self, block.next_block);
			emit_next_block = false;
		}
		break;

	case SPIRBlock::Select:
		// True if MergeToSelectForLoop or MergeToSelectContinueForLoop succeeded.
		if (select_branch_to_true_block)
		{
			if (force_complex_continue_block)
			{
				assert(block.true_block == block.continue_block);

				// We're going to emit a continue block directly here, so make sure it's marked as complex.
				auto &complex_continue = get<SPIRBlock>(block.continue_block).complex_continue;
				bool old_complex = complex_continue;
				complex_continue = true;
				branch(block.self, block.true_block);
				complex_continue = old_complex;
			}
			else
				branch(block.self, block.true_block);
		}
		else if (select_branch_to_false_block)
		{
			if (force_complex_continue_block)
			{
				assert(block.false_block == block.continue_block);

				// We're going to emit a continue block directly here, so make sure it's marked as complex.
				auto &complex_continue = get<SPIRBlock>(block.continue_block).complex_continue;
				bool old_complex = complex_continue;
				complex_continue = true;
				branch(block.self, block.false_block);
				complex_continue = old_complex;
			}
			else
				branch(block.self, block.false_block);
		}
		else
			branch(block.self, block.condition, block.true_block, block.false_block);
		break;

	case SPIRBlock::MultiSelect:
	{
		auto &type = expression_type(block.condition);
		bool unsigned_case = type.basetype == SPIRType::UInt || type.basetype == SPIRType::UShort ||
		                     type.basetype == SPIRType::UByte || type.basetype == SPIRType::UInt64;

		if (block.merge == SPIRBlock::MergeNone)
			SPIRV_CROSS_THROW("Switch statement is not structured");

		if (!backend.support_64bit_switch && (type.basetype == SPIRType::UInt64 || type.basetype == SPIRType::Int64))
		{
			// SPIR-V spec suggests this is allowed, but we cannot support it in higher level languages.
			SPIRV_CROSS_THROW("Cannot use 64-bit switch selectors.");
		}

		const char *label_suffix = "";
		if (type.basetype == SPIRType::UInt && backend.uint32_t_literal_suffix)
			label_suffix = "u";
		else if (type.basetype == SPIRType::Int64 && backend.support_64bit_switch)
			label_suffix = "l";
		else if (type.basetype == SPIRType::UInt64 && backend.support_64bit_switch)
			label_suffix = "ul";
		else if (type.basetype == SPIRType::UShort)
			label_suffix = backend.uint16_t_literal_suffix;
		else if (type.basetype == SPIRType::Short)
			label_suffix = backend.int16_t_literal_suffix;

		current_emitting_switch_stack.push_back(&block);

		if (block.need_ladder_break)
			statement("bool _", block.self, "_ladder_break = false;");

		// Find all unique case constructs.
		unordered_map<uint32_t, SmallVector<uint64_t>> case_constructs;
		SmallVector<uint32_t> block_declaration_order;
		SmallVector<uint64_t> literals_to_merge;

		// If a switch case branches to the default block for some reason, we can just remove that literal from consideration
		// and let the default: block handle it.
		// 2.11 in SPIR-V spec states that for fall-through cases, there is a very strict declaration order which we can take advantage of here.
		// We only need to consider possible fallthrough if order[i] branches to order[i + 1].
		auto &cases = get_case_list(block);
		for (auto &c : cases)
		{
			if (c.block != block.next_block && c.block != block.default_block)
			{
				if (!case_constructs.count(c.block))
					block_declaration_order.push_back(c.block);
				case_constructs[c.block].push_back(c.value);
			}
			else if (c.block == block.next_block && block.default_block != block.next_block)
			{
				// We might have to flush phi inside specific case labels.
				// If we can piggyback on default:, do so instead.
				literals_to_merge.push_back(c.value);
			}
		}

		// Empty literal array -> default.
		if (block.default_block != block.next_block)
		{
			auto &default_block = get<SPIRBlock>(block.default_block);

			// We need to slide in the default block somewhere in this chain
			// if there are fall-through scenarios since the default is declared separately in OpSwitch.
			// Only consider trivial fall-through cases here.
			size_t num_blocks = block_declaration_order.size();
			bool injected_block = false;

			for (size_t i = 0; i < num_blocks; i++)
			{
				auto &case_block = get<SPIRBlock>(block_declaration_order[i]);
				if (execution_is_direct_branch(case_block, default_block))
				{
					// Fallthrough to default block, we must inject the default block here.
					block_declaration_order.insert(begin(block_declaration_order) + i + 1, block.default_block);
					injected_block = true;
					break;
				}
				else if (execution_is_direct_branch(default_block, case_block))
				{
					// Default case is falling through to another case label, we must inject the default block here.
					block_declaration_order.insert(begin(block_declaration_order) + i, block.default_block);
					injected_block = true;
					break;
				}
			}

			// Order does not matter.
			if (!injected_block)
				block_declaration_order.push_back(block.default_block);
			else if (is_legacy_es())
				SPIRV_CROSS_THROW("Default case label fallthrough to other case label is not supported in ESSL 1.0.");

			case_constructs[block.default_block] = {};
		}

		size_t num_blocks = block_declaration_order.size();

		const auto to_case_label = [](uint64_t literal, uint32_t width, bool is_unsigned_case) -> string
		{
			if (is_unsigned_case)
				return convert_to_string(literal);

			// For smaller cases, the literals are compiled as 32 bit wide
			// literals so we don't need to care for all sizes specifically.
			if (width <= 32)
			{
				return convert_to_string(int64_t(int32_t(literal)));
			}

			return convert_to_string(int64_t(literal));
		};

		const auto to_legacy_case_label = [&](uint32_t condition, const SmallVector<uint64_t> &labels,
		                                      const char *suffix) -> string {
			string ret;
			size_t count = labels.size();
			for (size_t i = 0; i < count; i++)
			{
				if (i)
					ret += " || ";
				ret += join(count > 1 ? "(" : "", to_enclosed_expression(condition), " == ", labels[i], suffix,
				            count > 1 ? ")" : "");
			}
			return ret;
		};

		// We need to deal with a complex scenario for OpPhi. If we have case-fallthrough and Phi in the picture,
		// we need to flush phi nodes outside the switch block in a branch,
		// and skip any Phi handling inside the case label to make fall-through work as expected.
		// This kind of code-gen is super awkward and it's a last resort. Normally we would want to handle this
		// inside the case label if at all possible.
		for (size_t i = 1; backend.support_case_fallthrough && i < num_blocks; i++)
		{
			if (flush_phi_required(block.self, block_declaration_order[i]) &&
			    flush_phi_required(block_declaration_order[i - 1], block_declaration_order[i]))
			{
				uint32_t target_block = block_declaration_order[i];

				// Make sure we flush Phi, it might have been marked to be ignored earlier.
				get<SPIRBlock>(target_block).ignore_phi_from_block = 0;

				auto &literals = case_constructs[target_block];

				if (literals.empty())
				{
					// Oh boy, gotta make a complete negative test instead! o.o
					// Find all possible literals that would *not* make us enter the default block.
					// If none of those literals match, we flush Phi ...
					SmallVector<string> conditions;
					for (size_t j = 0; j < num_blocks; j++)
					{
						auto &negative_literals = case_constructs[block_declaration_order[j]];
						for (auto &case_label : negative_literals)
							conditions.push_back(join(to_enclosed_expression(block.condition),
							                          " != ", to_case_label(case_label, type.width, unsigned_case)));
					}

					statement("if (", merge(conditions, " && "), ")");
					begin_scope();
					flush_phi(block.self, target_block);
					end_scope();
				}
				else
				{
					SmallVector<string> conditions;
					conditions.reserve(literals.size());
					for (auto &case_label : literals)
						conditions.push_back(join(to_enclosed_expression(block.condition),
						                          " == ", to_case_label(case_label, type.width, unsigned_case)));
					statement("if (", merge(conditions, " || "), ")");
					begin_scope();
					flush_phi(block.self, target_block);
					end_scope();
				}

				// Mark the block so that we don't flush Phi from header to case label.
				get<SPIRBlock>(target_block).ignore_phi_from_block = block.self;
			}
		}

		// If there is only one default block, and no cases, this is a case where SPIRV-opt decided to emulate
		// non-structured exits with the help of a switch block.
		// This is buggy on FXC, so just emit the logical equivalent of a do { } while(false), which is more idiomatic.
		bool block_like_switch = cases.empty();

		// If this is true, the switch is completely meaningless, and we should just avoid it.
		bool collapsed_switch = block_like_switch && block.default_block == block.next_block;

		if (!collapsed_switch)
		{
			if (block_like_switch || is_legacy_es())
			{
				// ESSL 1.0 is not guaranteed to support do/while.
				if (is_legacy_es())
				{
					uint32_t counter = statement_count;
					statement("for (int spvDummy", counter, " = 0; spvDummy", counter, " < 1; spvDummy", counter,
					          "++)");
				}
				else
					statement("do");
			}
			else
			{
				emit_block_hints(block);
				statement("switch (", to_unpacked_expression(block.condition), ")");
			}
			begin_scope();
		}

		for (size_t i = 0; i < num_blocks; i++)
		{
			uint32_t target_block = block_declaration_order[i];
			auto &literals = case_constructs[target_block];

			if (literals.empty())
			{
				// Default case.
				if (!block_like_switch)
				{
					if (is_legacy_es())
						statement("else");
					else
						statement("default:");
				}
			}
			else
			{
				if (is_legacy_es())
				{
					statement((i ? "else " : ""), "if (", to_legacy_case_label(block.condition, literals, label_suffix),
					          ")");
				}
				else
				{
					for (auto &case_literal : literals)
					{
						// The case label value must be sign-extended properly in SPIR-V, so we can assume 32-bit values here.
						statement("case ", to_case_label(case_literal, type.width, unsigned_case), label_suffix, ":");
					}
				}
			}

			auto &case_block = get<SPIRBlock>(target_block);
			if (backend.support_case_fallthrough && i + 1 < num_blocks &&
			    execution_is_direct_branch(case_block, get<SPIRBlock>(block_declaration_order[i + 1])))
			{
				// We will fall through here, so just terminate the block chain early.
				// We still need to deal with Phi potentially.
				// No need for a stack-like thing here since we only do fall-through when there is a
				// single trivial branch to fall-through target..
				current_emitting_switch_fallthrough = true;
			}
			else
				current_emitting_switch_fallthrough = false;

			if (!block_like_switch)
				begin_scope();
			branch(block.self, target_block);
			if (!block_like_switch)
				end_scope();

			current_emitting_switch_fallthrough = false;
		}

		// Might still have to flush phi variables if we branch from loop header directly to merge target.
		// This is supposed to emit all cases where we branch from header to merge block directly.
		// There are two main scenarios where cannot rely on default fallthrough.
		// - There is an explicit default: label already.
		//   In this case, literals_to_merge need to form their own "default" case, so that we avoid executing that block.
		// - Header -> Merge requires flushing PHI. In this case, we need to collect all cases and flush PHI there.
		bool header_merge_requires_phi = flush_phi_required(block.self, block.next_block);
		bool need_fallthrough_block = block.default_block == block.next_block || !literals_to_merge.empty();
		if (!collapsed_switch && ((header_merge_requires_phi && need_fallthrough_block) || !literals_to_merge.empty()))
		{
			for (auto &case_literal : literals_to_merge)
				statement("case ", to_case_label(case_literal, type.width, unsigned_case), label_suffix, ":");

			if (block.default_block == block.next_block)
			{
				if (is_legacy_es())
					statement("else");
				else
					statement("default:");
			}

			begin_scope();
			flush_phi(block.self, block.next_block);
			statement("break;");
			end_scope();
		}

		if (!collapsed_switch)
		{
			if (block_like_switch && !is_legacy_es())
				end_scope_decl("while(false)");
			else
				end_scope();
		}
		else
			flush_phi(block.self, block.next_block);

		if (block.need_ladder_break)
		{
			statement("if (_", block.self, "_ladder_break)");
			begin_scope();
			statement("break;");
			end_scope();
		}

		current_emitting_switch_stack.pop_back();
		break;
	}

	case SPIRBlock::Return:
	{
		for (auto &line : current_function->fixup_hooks_out)
			line();

		if (processing_entry_point)
			emit_fixup();

		auto &cfg = get_cfg_for_current_function();

		if (block.return_value)
		{
			auto &type = expression_type(block.return_value);
			if (!type.array.empty() && !backend.can_return_array)
			{
				// If we cannot return arrays, we will have a special out argument we can write to instead.
				// The backend is responsible for setting this up, and redirection the return values as appropriate.
				if (ir.ids[block.return_value].get_type() != TypeUndef)
				{
					emit_array_copy("spvReturnValue", 0, block.return_value, StorageClassFunction,
					                get_expression_effective_storage_class(block.return_value));
				}

				if (!cfg.node_terminates_control_flow_in_sub_graph(current_function->entry_block, block.self) ||
				    block.loop_dominator != BlockID(SPIRBlock::NoDominator))
				{
					statement("return;");
				}
			}
			else
			{
				// OpReturnValue can return Undef, so don't emit anything for this case.
				if (ir.ids[block.return_value].get_type() != TypeUndef)
					statement("return ", to_unpacked_expression(block.return_value), ";");
			}
		}
		else if (!cfg.node_terminates_control_flow_in_sub_graph(current_function->entry_block, block.self) ||
		         block.loop_dominator != BlockID(SPIRBlock::NoDominator))
		{
			// If this block is the very final block and not called from control flow,
			// we do not need an explicit return which looks out of place. Just end the function here.
			// In the very weird case of for(;;) { return; } executing return is unconditional,
			// but we actually need a return here ...
			statement("return;");
		}
		break;
	}

	// If the Kill is terminating a block with a (probably synthetic) return value, emit a return value statement.
	case SPIRBlock::Kill:
		statement(backend.discard_literal, ";");
		if (block.return_value)
			statement("return ", to_unpacked_expression(block.return_value), ";");
		break;

	case SPIRBlock::Unreachable:
	{
		// Avoid emitting false fallthrough, which can happen for
		// if (cond) break; else discard; inside a case label.
		// Discard is not always implementable as a terminator.

		auto &cfg = get_cfg_for_current_function();
		bool inner_dominator_is_switch = false;
		ID id = block.self;

		while (id)
		{
			auto &iter_block = get<SPIRBlock>(id);
			if (iter_block.terminator == SPIRBlock::MultiSelect ||
			    iter_block.merge == SPIRBlock::MergeLoop)
			{
				ID next_block = iter_block.merge == SPIRBlock::MergeLoop ?
				                iter_block.merge_block : iter_block.next_block;
				bool outside_construct = next_block && cfg.find_common_dominator(next_block, block.self) == next_block;
				if (!outside_construct)
				{
					inner_dominator_is_switch = iter_block.terminator == SPIRBlock::MultiSelect;
					break;
				}
			}

			if (cfg.get_preceding_edges(id).empty())
				break;

			id = cfg.get_immediate_dominator(id);
		}

		if (inner_dominator_is_switch)
			statement("break; // unreachable workaround");

		emit_next_block = false;
		break;
	}

	case SPIRBlock::IgnoreIntersection:
		statement("ignoreIntersectionEXT;");
		break;

	case SPIRBlock::TerminateRay:
		statement("terminateRayEXT;");
		break;

	case SPIRBlock::EmitMeshTasks:
		emit_mesh_tasks(block);
		break;

	default:
		SPIRV_CROSS_THROW("Unimplemented block terminator.");
	}

	if (block.next_block && emit_next_block)
	{
		// If we hit this case, we're dealing with an unconditional branch, which means we will output
		// that block after this. If we had selection merge, we already flushed phi variables.
		if (block.merge != SPIRBlock::MergeSelection)
		{
			flush_phi(block.self, block.next_block);
			// For a direct branch, need to remember to invalidate expressions in the next linear block instead.
			get<SPIRBlock>(block.next_block).invalidate_expressions = block.invalidate_expressions;
		}

		// For switch fallthrough cases, we terminate the chain here, but we still need to handle Phi.
		if (!current_emitting_switch_fallthrough)
		{
			// For merge selects we might have ignored the fact that a merge target
			// could have been a break; or continue;
			// We will need to deal with it here.
			if (is_loop_break(block.next_block))
			{
				// Cannot check for just break, because switch statements will also use break.
				assert(block.merge == SPIRBlock::MergeSelection);
				statement("break;");
			}
			else if (is_continue(block.next_block))
			{
				assert(block.merge == SPIRBlock::MergeSelection);
				branch_to_continue(block.self, block.next_block);
			}
			else if (BlockID(block.self) != block.next_block)
				emit_block_chain(get<SPIRBlock>(block.next_block));
		}
	}

	if (block.merge == SPIRBlock::MergeLoop)
	{
		if (continue_type == SPIRBlock::DoWhileLoop)
		{
			// Make sure that we run the continue block to get the expressions set, but this
			// should become an empty string.
			// We have no fallbacks if we cannot forward everything to temporaries ...
			const auto &continue_block = get<SPIRBlock>(block.continue_block);
			bool positive_test = execution_is_noop(get<SPIRBlock>(continue_block.true_block),
			                                       get<SPIRBlock>(continue_block.loop_dominator));

			uint32_t current_count = statement_count;
			auto statements = emit_continue_block(block.continue_block, positive_test, !positive_test);
			if (statement_count != current_count)
			{
				// The DoWhile block has side effects, force ComplexLoop pattern next pass.
				get<SPIRBlock>(block.continue_block).complex_continue = true;
				force_recompile();
			}

			// Might have to invert the do-while test here.
			auto condition = to_expression(continue_block.condition);
			if (!positive_test)
				condition = join("!", enclose_expression(condition));

			end_scope_decl(join("while (", condition, ")"));
		}
		else
			end_scope();

		loop_level_saver.release();

		// We cannot break out of two loops at once, so don't check for break; here.
		// Using block.self as the "from" block isn't quite right, but it has the same scope
		// and dominance structure, so it's fine.
		if (is_continue(block.merge_block))
			branch_to_continue(block.self, block.merge_block);
		else
			emit_block_chain(get<SPIRBlock>(block.merge_block));
	}

	// Forget about control dependent expressions now.
	block.invalidate_expressions.clear();

	// After we return, we must be out of scope, so if we somehow have to re-emit this function,
	// re-declare variables if necessary.
	assert(rearm_dominated_variables.size() == block.dominated_variables.size());
	for (size_t i = 0; i < block.dominated_variables.size(); i++)
	{
		uint32_t var = block.dominated_variables[i];
		get<SPIRVariable>(var).deferred_declaration = rearm_dominated_variables[i];
	}

	// Just like for deferred declaration, we need to forget about loop variable enable
	// if our block chain is reinstantiated later.
	for (auto &var_id : block.loop_variables)
		get<SPIRVariable>(var_id).loop_variable_enable = false;
}

void CompilerHLSL::emit_hoisted_temporaries(SmallVector<pair<TypeID, ID>> &temporaries)
{
	// If we need to force temporaries for certain IDs due to continue blocks, do it before starting loop header.
	// Need to sort these to ensure that reference output is stable.
	sort(begin(temporaries), end(temporaries),
	     [](const pair<TypeID, ID> &a, const pair<TypeID, ID> &b) { return a.second < b.second; });

	for (auto &tmp : temporaries)
	{
		auto &type = get<SPIRType>(tmp.first);

		// There are some rare scenarios where we are asked to declare pointer types as hoisted temporaries.
		// This should be ignored unless we're doing actual variable pointers and backend supports it.
		// Access chains cannot normally be lowered to temporaries in GLSL and HLSL.
		if (type.pointer && !backend.native_pointers)
			continue;

		add_local_variable_name(tmp.second);
		auto &flags = get_decoration_bitset(tmp.second);

		// Not all targets support pointer literals, so don't bother with that case.
		string initializer;
		if (options.force_zero_initialized_variables && type_can_zero_initialize(type))
			initializer = join(" = ", to_zero_initialized_expression(tmp.first));

		statement(flags_to_qualifiers_glsl(type, flags), variable_decl(type, to_name(tmp.second)), initializer, ";");

		hoisted_temporaries.insert(tmp.second);
		forced_temporaries.insert(tmp.second);

		// The temporary might be read from before it's assigned, set up the expression now.
		set<SPIRExpression>(tmp.second, to_name(tmp.second), tmp.first, true);

		// If we have hoisted temporaries in multi-precision contexts, emit that here too ...
		// We will not be able to analyze hoisted-ness for dependent temporaries that we hallucinate here.
		auto mirrored_precision_itr = temporary_to_mirror_precision_alias.find(tmp.second);
		if (mirrored_precision_itr != temporary_to_mirror_precision_alias.end())
		{
			uint32_t mirror_id = mirrored_precision_itr->second;
			auto &mirror_flags = get_decoration_bitset(mirror_id);
			statement(flags_to_qualifiers_glsl(type, mirror_flags),
			          variable_decl(type, to_name(mirror_id)),
			          initializer, ";");
			// The temporary might be read from before it's assigned, set up the expression now.
			set<SPIRExpression>(mirror_id, to_name(mirror_id), tmp.first, true);
			hoisted_temporaries.insert(mirror_id);
		}
	}
}

void CompilerHLSL::flush_undeclared_variables(SPIRBlock &block)
{
	for (auto &v : block.dominated_variables)
		flush_variable_declaration(v);
}

bool CompilerHLSL::attempt_emit_loop_header(SPIRBlock &block, SPIRBlock::Method method)
{
	SPIRBlock::ContinueBlockType continue_type = continue_block_type(get<SPIRBlock>(block.continue_block));

	if (method == SPIRBlock::MergeToSelectForLoop || method == SPIRBlock::MergeToSelectContinueForLoop)
	{
		uint32_t current_count = statement_count;
		// If we're trying to create a true for loop,
		// we need to make sure that all opcodes before branch statement do not actually emit any code.
		// We can then take the condition expression and create a for (; cond ; ) { body; } structure instead.
		emit_block_instructions_with_masked_debug(block);

		bool condition_is_temporary = forced_temporaries.find(block.condition) == end(forced_temporaries);

		// This can work! We only did trivial things which could be forwarded in block body!
		if (current_count == statement_count && condition_is_temporary)
		{
			switch (continue_type)
			{
			case SPIRBlock::ForLoop:
			{
				// This block may be a dominating block, so make sure we flush undeclared variables before building the for loop header.
				flush_undeclared_variables(block);

				// Important that we do this in this order because
				// emitting the continue block can invalidate the condition expression.
				auto initializer = emit_for_loop_initializers(block);
				auto condition = to_expression(block.condition);

				// Condition might have to be inverted.
				if (execution_is_noop(get<SPIRBlock>(block.true_block), get<SPIRBlock>(block.merge_block)))
					condition = join("!", enclose_expression(condition));

				emit_block_hints(block);
				if (method != SPIRBlock::MergeToSelectContinueForLoop)
				{
					auto continue_block = emit_continue_block(block.continue_block, false, false);
					statement("for (", initializer, "; ", condition, "; ", continue_block, ")");
				}
				else
					statement("for (", initializer, "; ", condition, "; )");
				break;
			}

			case SPIRBlock::WhileLoop:
			{
				// This block may be a dominating block, so make sure we flush undeclared variables before building the while loop header.
				flush_undeclared_variables(block);
				emit_while_loop_initializers(block);
				emit_block_hints(block);

				auto condition = to_expression(block.condition);
				// Condition might have to be inverted.
				if (execution_is_noop(get<SPIRBlock>(block.true_block), get<SPIRBlock>(block.merge_block)))
					condition = join("!", enclose_expression(condition));

				statement("while (", condition, ")");
				break;
			}

			default:
				block.disable_block_optimization = true;
				force_recompile();
				begin_scope(); // We'll see an end_scope() later.
				return false;
			}

			begin_scope();
			return true;
		}
		else
		{
			block.disable_block_optimization = true;
			force_recompile();
			begin_scope(); // We'll see an end_scope() later.
			return false;
		}
	}
	else if (method == SPIRBlock::MergeToDirectForLoop)
	{
		auto &child = get<SPIRBlock>(block.next_block);

		// This block may be a dominating block, so make sure we flush undeclared variables before building the for loop header.
		flush_undeclared_variables(child);

		uint32_t current_count = statement_count;

		// If we're trying to create a true for loop,
		// we need to make sure that all opcodes before branch statement do not actually emit any code.
		// We can then take the condition expression and create a for (; cond ; ) { body; } structure instead.
		emit_block_instructions_with_masked_debug(child);

		bool condition_is_temporary = forced_temporaries.find(child.condition) == end(forced_temporaries);

		if (current_count == statement_count && condition_is_temporary)
		{
			uint32_t target_block = child.true_block;

			switch (continue_type)
			{
			case SPIRBlock::ForLoop:
			{
				// Important that we do this in this order because
				// emitting the continue block can invalidate the condition expression.
				auto initializer = emit_for_loop_initializers(block);
				auto condition = to_expression(child.condition);

				// Condition might have to be inverted.
				if (execution_is_noop(get<SPIRBlock>(child.true_block), get<SPIRBlock>(block.merge_block)))
				{
					condition = join("!", enclose_expression(condition));
					target_block = child.false_block;
				}

				auto continue_block = emit_continue_block(block.continue_block, false, false);
				emit_block_hints(block);
				statement("for (", initializer, "; ", condition, "; ", continue_block, ")");
				break;
			}

			case SPIRBlock::WhileLoop:
			{
				emit_while_loop_initializers(block);
				emit_block_hints(block);

				auto condition = to_expression(child.condition);
				// Condition might have to be inverted.
				if (execution_is_noop(get<SPIRBlock>(child.true_block), get<SPIRBlock>(block.merge_block)))
				{
					condition = join("!", enclose_expression(condition));
					target_block = child.false_block;
				}

				statement("while (", condition, ")");
				break;
			}

			default:
				block.disable_block_optimization = true;
				force_recompile();
				begin_scope(); // We'll see an end_scope() later.
				return false;
			}

			begin_scope();
			branch(child.self, target_block);
			return true;
		}
		else
		{
			block.disable_block_optimization = true;
			force_recompile();
			begin_scope(); // We'll see an end_scope() later.
			return false;
		}
	}
	else
		return false;
}

void CompilerHLSL::emit_block_instructions(SPIRBlock &block)
{
	current_emitting_block = &block;

	if (backend.requires_relaxed_precision_analysis)
	{
		// If PHI variables are consumed in unexpected precision contexts, copy them here.
		for (size_t i = 0, n = block.phi_variables.size(); i < n; i++)
		{
			auto &phi = block.phi_variables[i];

			// Ensure we only copy once. We know a-priori that this array will lay out
			// the same function variables together.
			if (i && block.phi_variables[i - 1].function_variable == phi.function_variable)
				continue;

			auto itr = temporary_to_mirror_precision_alias.find(phi.function_variable);
			if (itr != temporary_to_mirror_precision_alias.end())
			{
				// Explicitly, we don't want to inherit RelaxedPrecision state in this CopyObject,
				// so it helps to have handle_instruction_precision() on the outside of emit_instruction().
				EmbeddedInstruction inst;
				inst.op = OpCopyObject;
				inst.length = 3;
				inst.ops.push_back(expression_type_id(itr->first));
				inst.ops.push_back(itr->second);
				inst.ops.push_back(itr->first);
				emit_instruction(inst);
			}
		}
	}

	for (auto &op : block.ops)
	{
		auto temporary_copy = handle_instruction_precision(op);
		emit_instruction(op);
		if (temporary_copy.dst_id)
		{
			// Explicitly, we don't want to inherit RelaxedPrecision state in this CopyObject,
			// so it helps to have handle_instruction_precision() on the outside of emit_instruction().
			EmbeddedInstruction inst;
			inst.op = OpCopyObject;
			inst.length = 3;
			inst.ops.push_back(expression_type_id(temporary_copy.src_id));
			inst.ops.push_back(temporary_copy.dst_id);
			inst.ops.push_back(temporary_copy.src_id);

			// Never attempt to hoist mirrored temporaries.
			// They are hoisted in lock-step with their parents.
			block_temporary_hoisting = true;
			emit_instruction(inst);
			block_temporary_hoisting = false;
		}
	}

	current_emitting_block = nullptr;
}

CompilerHLSL::TemporaryCopy CompilerHLSL::handle_instruction_precision(const Instruction &instruction)
{
	auto ops = stream_mutable(instruction);
	auto opcode = static_cast<Op>(instruction.op);
	uint32_t length = instruction.length;

	if (backend.requires_relaxed_precision_analysis)
	{
		if (length > 2)
		{
			uint32_t forwarding_length = length - 2;

			if (opcode_is_precision_sensitive_operation(opcode))
				analyze_precision_requirements(ops[0], ops[1], &ops[2], forwarding_length);
			else if (opcode == OpExtInst && length >= 5 && get<SPIRExtension>(ops[2]).ext == SPIRExtension::GLSL)
				analyze_precision_requirements(ops[0], ops[1], &ops[4], forwarding_length - 2);
			else if (opcode_is_precision_forwarding_instruction(opcode, forwarding_length))
				forward_relaxed_precision(ops[1], &ops[2], forwarding_length);
		}

		uint32_t result_type = 0, result_id = 0;
		if (instruction_to_result_type(result_type, result_id, opcode, ops, length))
		{
			auto itr = temporary_to_mirror_precision_alias.find(ops[1]);
			if (itr != temporary_to_mirror_precision_alias.end())
				return { itr->second, itr->first };
		}
	}

	return {};
}

void CompilerHLSL::branch(BlockID from, BlockID to)
{
	flush_phi(from, to);
	flush_control_dependent_expressions(from);

	bool to_is_continue = is_continue(to);

	// This is only a continue if we branch to our loop dominator.
	if ((ir.block_meta[to] & ParsedIR::BLOCK_META_LOOP_HEADER_BIT) != 0 && get<SPIRBlock>(from).loop_dominator == to)
	{
		// This can happen if we had a complex continue block which was emitted.
		// Once the continue block tries to branch to the loop header, just emit continue;
		// and end the chain here.
		statement("continue;");
	}
	else if (from != to && is_break(to))
	{
		// We cannot break to ourselves, so check explicitly for from != to.
		// This case can trigger if a loop header is all three of these things:
		// - Continue block
		// - Loop header
		// - Break merge target all at once ...

		// Very dirty workaround.
		// Switch constructs are able to break, but they cannot break out of a loop at the same time,
		// yet SPIR-V allows it.
		// Only sensible solution is to make a ladder variable, which we declare at the top of the switch block,
		// write to the ladder here, and defer the break.
		// The loop we're breaking out of must dominate the switch block, or there is no ladder breaking case.
		if (is_loop_break(to))
		{
			for (size_t n = current_emitting_switch_stack.size(); n; n--)
			{
				auto *current_emitting_switch = current_emitting_switch_stack[n - 1];

				if (current_emitting_switch &&
				    current_emitting_switch->loop_dominator != BlockID(SPIRBlock::NoDominator) &&
				    get<SPIRBlock>(current_emitting_switch->loop_dominator).merge_block == to)
				{
					if (!current_emitting_switch->need_ladder_break)
					{
						force_recompile();
						current_emitting_switch->need_ladder_break = true;
					}

					statement("_", current_emitting_switch->self, "_ladder_break = true;");
				}
				else
					break;
			}
		}
		statement("break;");
	}
	else if (to_is_continue || from == to)
	{
		// For from == to case can happen for a do-while loop which branches into itself.
		// We don't mark these cases as continue blocks, but the only possible way to branch into
		// ourselves is through means of continue blocks.

		// If we are merging to a continue block, there is no need to emit the block chain for continue here.
		// We can branch to the continue block after we merge execution.

		// Here we make use of structured control flow rules from spec:
		// 2.11: - the merge block declared by a header block cannot be a merge block declared by any other header block
		//       - each header block must strictly dominate its merge block, unless the merge block is unreachable in the CFG
		// If we are branching to a merge block, we must be inside a construct which dominates the merge block.
		auto &block_meta = ir.block_meta[to];
		bool branching_to_merge =
		    (block_meta & (ParsedIR::BLOCK_META_SELECTION_MERGE_BIT | ParsedIR::BLOCK_META_MULTISELECT_MERGE_BIT |
		                   ParsedIR::BLOCK_META_LOOP_MERGE_BIT)) != 0;
		if (!to_is_continue || !branching_to_merge)
			branch_to_continue(from, to);
	}
	else if (!is_conditional(to))
		emit_block_chain(get<SPIRBlock>(to));

	// It is important that we check for break before continue.
	// A block might serve two purposes, a break block for the inner scope, and
	// a continue block in the outer scope.
	// Inner scope always takes precedence.
}

void CompilerHLSL::branch(BlockID from, uint32_t cond, BlockID true_block, BlockID false_block)
{
	auto &from_block = get<SPIRBlock>(from);
	BlockID merge_block = from_block.merge == SPIRBlock::MergeSelection ? from_block.next_block : BlockID(0);

	// If we branch directly to our selection merge target, we don't need a code path.
	bool true_block_needs_code = true_block != merge_block || flush_phi_required(from, true_block);
	bool false_block_needs_code = false_block != merge_block || flush_phi_required(from, false_block);

	if (!true_block_needs_code && !false_block_needs_code)
		return;

	// We might have a loop merge here. Only consider selection flattening constructs.
	// Loop hints are handled explicitly elsewhere.
	if (from_block.hint == SPIRBlock::HintFlatten || from_block.hint == SPIRBlock::HintDontFlatten)
		emit_block_hints(from_block);

	if (true_block_needs_code)
	{
		statement("if (", to_expression(cond), ")");
		begin_scope();
		branch(from, true_block);
		end_scope();

		if (false_block_needs_code)
		{
			statement("else");
			begin_scope();
			branch(from, false_block);
			end_scope();
		}
	}
	else if (false_block_needs_code)
	{
		// Only need false path, use negative conditional.
		statement("if (!", to_enclosed_expression(cond), ")");
		begin_scope();
		branch(from, false_block);
		end_scope();
	}
}

void CompilerHLSL::branch_to_continue(BlockID from, BlockID to)
{
	auto &to_block = get<SPIRBlock>(to);
	if (from == to)
		return;

	assert(is_continue(to));
	if (to_block.complex_continue)
	{
		// Just emit the whole block chain as is.
		auto usage_counts = expression_usage_counts;

		emit_block_chain(to_block);

		// Expression usage counts are moot after returning from the continue block.
		expression_usage_counts = usage_counts;
	}
	else
	{
		auto &from_block = get<SPIRBlock>(from);
		bool outside_control_flow = false;
		uint32_t loop_dominator = 0;

		// FIXME: Refactor this to not use the old loop_dominator tracking.
		if (from_block.merge_block)
		{
			// If we are a loop header, we don't set the loop dominator,
			// so just use "self" here.
			loop_dominator = from;
		}
		else if (from_block.loop_dominator != BlockID(SPIRBlock::NoDominator))
		{
			loop_dominator = from_block.loop_dominator;
		}

		if (loop_dominator != 0)
		{
			auto &cfg = get_cfg_for_current_function();

			// For non-complex continue blocks, we implicitly branch to the continue block
			// by having the continue block be part of the loop header in for (; ; continue-block).
			outside_control_flow = cfg.node_terminates_control_flow_in_sub_graph(loop_dominator, from);
		}

		// Some simplification for for-loops. We always end up with a useless continue;
		// statement since we branch to a loop block.
		// Walk the CFG, if we unconditionally execute the block calling continue assuming we're in the loop block,
		// we can avoid writing out an explicit continue statement.
		// Similar optimization to return statements if we know we're outside flow control.
		if (!outside_control_flow)
			statement("continue;");
	}
}

void CompilerHLSL::flush_phi(BlockID from, BlockID to)
{
	auto &child = get<SPIRBlock>(to);
	if (child.ignore_phi_from_block == from)
		return;

	unordered_set<uint32_t> temporary_phi_variables;

	for (auto itr = begin(child.phi_variables); itr != end(child.phi_variables); ++itr)
	{
		auto &phi = *itr;

		if (phi.parent == from)
		{
			auto &var = get<SPIRVariable>(phi.function_variable);

			// A Phi variable might be a loop variable, so flush to static expression.
			if (var.loop_variable && !var.loop_variable_enable)
				var.static_expression = phi.local_variable;
			else
			{
				flush_variable_declaration(phi.function_variable);

				// Check if we are going to write to a Phi variable that another statement will read from
				// as part of another Phi node in our target block.
				// For this case, we will need to copy phi.function_variable to a temporary, and use that for future reads.
				// This is judged to be extremely rare, so deal with it here using a simple, but suboptimal algorithm.
				bool need_saved_temporary =
				    find_if(itr + 1, end(child.phi_variables), [&](const SPIRBlock::Phi &future_phi) -> bool {
					    return future_phi.local_variable == ID(phi.function_variable) && future_phi.parent == from;
				    }) != end(child.phi_variables);

				if (need_saved_temporary)
				{
					// Need to make sure we declare the phi variable with a copy at the right scope.
					// We cannot safely declare a temporary here since we might be inside a continue block.
					if (!var.allocate_temporary_copy)
					{
						var.allocate_temporary_copy = true;
						force_recompile();
					}
					statement("_", phi.function_variable, "_copy", " = ", to_name(phi.function_variable), ";");
					temporary_phi_variables.insert(phi.function_variable);
				}

				// This might be called in continue block, so make sure we
				// use this to emit ESSL 1.0 compliant increments/decrements.
				auto lhs = to_expression(phi.function_variable);

				string rhs;
				if (temporary_phi_variables.count(phi.local_variable))
					rhs = join("_", phi.local_variable, "_copy");
				else
					rhs = to_pointer_expression(phi.local_variable);

				if (!optimize_read_modify_write(get<SPIRType>(var.basetype), lhs, rhs))
					statement(lhs, " = ", rhs, ";");
			}

			register_write(phi.function_variable);
		}
	}
}

string CompilerHLSL::to_pointer_expression(uint32_t id, bool register_expression_read)
{
	auto &type = expression_type(id);
	if (type.pointer && expression_is_lvalue(id) && !should_dereference(id))
		return address_of_expression(to_enclosed_expression(id, register_expression_read));
	else
		return to_unpacked_expression(id, register_expression_read);
}

bool CompilerHLSL::optimize_read_modify_write(const SPIRType &type, const string &lhs, const string &rhs)
{
	// Do this with strings because we have a very clear pattern we can check for and it avoids
	// adding lots of special cases to the code emission.
	if (rhs.size() < lhs.size() + 3)
		return false;

	// Do not optimize matrices. They are a bit awkward to reason about in general
	// (in which order does operation happen?), and it does not work on MSL anyways.
	if (type.vecsize > 1 && type.columns > 1)
		return false;

	auto index = rhs.find(lhs);
	if (index != 0)
		return false;

	// TODO: Shift operators, but it's not important for now.
	auto op = rhs.find_first_of("+-/*%|&^", lhs.size() + 1);
	if (op != lhs.size() + 1)
		return false;

	// Check that the op is followed by space. This excludes && and ||.
	if (rhs[op + 1] != ' ')
		return false;

	char bop = rhs[op];
	auto expr = rhs.substr(lhs.size() + 3);

	// Avoids false positives where we get a = a * b + c.
	// Normally, these expressions are always enclosed, but unexpected code paths may end up hitting this.
	if (needs_enclose_expression(expr))
		return false;

	// Try to find increments and decrements. Makes it look neater as += 1, -= 1 is fairly rare to see in real code.
	// Find some common patterns which are equivalent.
	if ((bop == '+' || bop == '-') && (expr == "1" || expr == "uint(1)" || expr == "1u" || expr == "int(1u)"))
		statement(lhs, bop, bop, ";");
	else
		statement(lhs, " ", bop, "= ", expr, ";");
	return true;
}

// FIXME: This currently cannot handle complex continue blocks
// as in do-while.
// This should be seen as a "trivial" continue block.
string CompilerHLSL::emit_continue_block(uint32_t continue_block, bool follow_true_block, bool follow_false_block)
{
	auto *block = &get<SPIRBlock>(continue_block);

	// While emitting the continue block, declare_temporary will check this
	// if we have to emit temporaries.
	current_continue_block = block;

	SmallVector<string> statements;

	// Capture all statements into our list.
	auto *old = redirect_statement;
	redirect_statement = &statements;

	// Stamp out all blocks one after each other.
	while ((ir.block_meta[block->self] & ParsedIR::BLOCK_META_LOOP_HEADER_BIT) == 0)
	{
		// Write out all instructions we have in this block.
		emit_block_instructions(*block);

		// For plain branchless for/while continue blocks.
		if (block->next_block)
		{
			flush_phi(continue_block, block->next_block);
			block = &get<SPIRBlock>(block->next_block);
		}
		// For do while blocks. The last block will be a select block.
		else if (block->true_block && follow_true_block)
		{
			flush_phi(continue_block, block->true_block);
			block = &get<SPIRBlock>(block->true_block);
		}
		else if (block->false_block && follow_false_block)
		{
			flush_phi(continue_block, block->false_block);
			block = &get<SPIRBlock>(block->false_block);
		}
		else
		{
			SPIRV_CROSS_THROW("Invalid continue block detected!");
		}
	}

	// Restore old pointer.
	redirect_statement = old;

	// Somewhat ugly, strip off the last ';' since we use ',' instead.
	// Ideally, we should select this behavior in statement().
	for (auto &s : statements)
	{
		if (!s.empty() && s.back() == ';')
			s.erase(s.size() - 1, 1);
	}

	current_continue_block = nullptr;
	return merge(statements);
}

void CompilerHLSL::emit_block_instructions_with_masked_debug(SPIRBlock &block)
{
	// Have to block debug instructions such as OpLine here, since it will be treated as a statement otherwise,
	// which breaks loop optimizations.
	// Any line directive would be declared outside the loop body, which would just be confusing either way.
	bool old_block_debug_directives = block_debug_directives;
	block_debug_directives = true;
	emit_block_instructions(block);
	block_debug_directives = old_block_debug_directives;
}

string CompilerHLSL::emit_for_loop_initializers(const SPIRBlock &block)
{
	if (block.loop_variables.empty())
		return "";

	bool same_types = for_loop_initializers_are_same_type(block);
	// We can only declare for loop initializers if all variables are of same type.
	// If we cannot do this, declare individual variables before the loop header.

	// We might have a loop variable candidate which was not assigned to for some reason.
	uint32_t missing_initializers = 0;
	for (auto &variable : block.loop_variables)
	{
		uint32_t expr = get<SPIRVariable>(variable).static_expression;

		// Sometimes loop variables are initialized with OpUndef, but we can just declare
		// a plain variable without initializer in this case.
		if (expr == 0 || ir.ids[expr].get_type() == TypeUndef)
			missing_initializers++;
	}

	if (block.loop_variables.size() == 1 && missing_initializers == 0)
	{
		return variable_decl(get<SPIRVariable>(block.loop_variables.front()));
	}
	else if (!same_types || missing_initializers == uint32_t(block.loop_variables.size()))
	{
		for (auto &loop_var : block.loop_variables)
			statement(variable_decl(get<SPIRVariable>(loop_var)), ";");
		return "";
	}
	else
	{
		// We have a mix of loop variables, either ones with a clear initializer, or ones without.
		// Separate the two streams.
		string expr;

		for (auto &loop_var : block.loop_variables)
		{
			uint32_t static_expr = get<SPIRVariable>(loop_var).static_expression;
			if (static_expr == 0 || ir.ids[static_expr].get_type() == TypeUndef)
			{
				statement(variable_decl(get<SPIRVariable>(loop_var)), ";");
			}
			else
			{
				auto &var = get<SPIRVariable>(loop_var);
				auto &type = get_variable_data_type(var);
				if (expr.empty())
				{
					// For loop initializers are of the form <type id = value, id = value, id = value, etc ...
					expr = join(to_qualifiers_glsl(var.self), type_to_glsl(type), " ");
				}
				else
				{
					expr += ", ";
					// In MSL, being based on C++, the asterisk marking a pointer
					// binds to the identifier, not the type.
					if (type.pointer)
						expr += "* ";
				}

				expr += join(to_name(loop_var), " = ", to_pointer_expression(var.static_expression));
			}
		}
		return expr;
	}
}

bool CompilerHLSL::for_loop_initializers_are_same_type(const SPIRBlock &block)
{
	if (block.loop_variables.size() <= 1)
		return true;

	uint32_t expected = 0;
	Bitset expected_flags;
	for (auto &var : block.loop_variables)
	{
		// Don't care about uninitialized variables as they will not be part of the initializers.
		uint32_t expr = get<SPIRVariable>(var).static_expression;
		if (expr == 0 || ir.ids[expr].get_type() == TypeUndef)
			continue;

		if (expected == 0)
		{
			expected = get<SPIRVariable>(var).basetype;
			expected_flags = get_decoration_bitset(var);
		}
		else if (expected != get<SPIRVariable>(var).basetype)
			return false;

		// Precision flags and things like that must also match.
		if (expected_flags != get_decoration_bitset(var))
			return false;
	}

	return true;
}

string CompilerHLSL::to_qualifiers_glsl(uint32_t id)
{
	auto &flags = get_decoration_bitset(id);
	string res;

	auto *var = maybe_get<SPIRVariable>(id);

	if (var && var->storage == StorageClassWorkgroup && !backend.shared_is_implied)
		res += "shared ";
	else if (var && var->storage == StorageClassTaskPayloadWorkgroupEXT && !backend.shared_is_implied)
		res += "taskPayloadSharedEXT ";

	res += to_interpolation_qualifiers(flags);
	if (var)
		res += to_storage_qualifiers_glsl(*var);

	auto &type = expression_type(id);
	if (type.image.dim != DimSubpassData && type.image.sampled == 2)
	{
		if (flags.get(DecorationCoherent))
			res += "coherent ";
		if (flags.get(DecorationRestrict))
			res += "restrict ";

		if (flags.get(DecorationNonWritable))
			res += "readonly ";

		bool formatted_load = type.image.format == ImageFormatUnknown;
		if (flags.get(DecorationNonReadable))
		{
			res += "writeonly ";
			formatted_load = false;
		}

		if (formatted_load)
		{
			if (!options.es)
				require_extension_internal("GL_EXT_shader_image_load_formatted");
			else
				SPIRV_CROSS_THROW("Cannot use GL_EXT_shader_image_load_formatted in ESSL.");
		}
	}

	res += to_precision_qualifiers_glsl(id);

	return res;
}

string CompilerHLSL::to_precision_qualifiers_glsl(uint32_t id)
{
	auto &type = expression_type(id);
	bool use_precision_qualifiers = backend.allow_precision_qualifiers;
	if (use_precision_qualifiers && (type.basetype == SPIRType::Image || type.basetype == SPIRType::SampledImage))
	{
		// Force mediump for the sampler type. We cannot declare 16-bit or smaller image types.
		auto &result_type = get<SPIRType>(type.image.type);
		if (result_type.width < 32)
			return "mediump ";
	}
	return flags_to_qualifiers_glsl(type, ir.meta[id].decoration.decoration_flags);
}

bool CompilerHLSL::variable_decl_is_remapped_storage(const SPIRVariable &var, StorageClass storage) const
{
	return var.storage == storage;
}

bool CompilerHLSL::expression_is_forwarded(uint32_t id) const
{
	return forwarded_temporaries.count(id) != 0;
}

string CompilerHLSL::constant_expression_vector(const SPIRConstant &c, uint32_t vector)
{
	auto type = get<SPIRType>(c.constant_type);
	type.columns = 1;

	auto scalar_type = type;
	scalar_type.vecsize = 1;

	string res;
	bool splat = backend.use_constructor_splatting && c.vector_size() > 1;
	bool swizzle_splat = backend.can_swizzle_scalar && c.vector_size() > 1;

	if (!type_is_floating_point(type))
	{
		// Cannot swizzle literal integers as a special case.
		swizzle_splat = false;
	}

	if (splat || swizzle_splat)
	{
		// Cannot use constant splatting if we have specialization constants somewhere in the vector.
		for (uint32_t i = 0; i < c.vector_size(); i++)
		{
			if (c.specialization_constant_id(vector, i) != 0)
			{
				splat = false;
				swizzle_splat = false;
				break;
			}
		}
	}

	if (splat || swizzle_splat)
	{
		if (type.width == 64)
		{
			uint64_t ident = c.scalar_u64(vector, 0);
			for (uint32_t i = 1; i < c.vector_size(); i++)
			{
				if (ident != c.scalar_u64(vector, i))
				{
					splat = false;
					swizzle_splat = false;
					break;
				}
			}
		}
		else
		{
			uint32_t ident = c.scalar(vector, 0);
			for (uint32_t i = 1; i < c.vector_size(); i++)
			{
				if (ident != c.scalar(vector, i))
				{
					splat = false;
					swizzle_splat = false;
				}
			}
		}
	}

	if (c.vector_size() > 1 && !swizzle_splat)
		res += type_to_glsl(type) + "(";

	switch (type.basetype)
	{
	case SPIRType::Half:
		if (splat || swizzle_splat)
		{
			res += convert_half_to_string(c, vector, 0);
			if (swizzle_splat)
				res = remap_swizzle(get<SPIRType>(c.constant_type), 1, res);
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
					res += convert_half_to_string(c, vector, i);

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::Float:
		if (splat || swizzle_splat)
		{
			res += convert_float_to_string(c, vector, 0);
			if (swizzle_splat)
				res = remap_swizzle(get<SPIRType>(c.constant_type), 1, res);
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
					res += convert_float_to_string(c, vector, i);

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::Double:
		if (splat || swizzle_splat)
		{
			res += convert_double_to_string(c, vector, 0);
			if (swizzle_splat)
				res = remap_swizzle(get<SPIRType>(c.constant_type), 1, res);
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
					res += convert_double_to_string(c, vector, i);

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::Int64:
	{
		auto tmp = type;
		tmp.vecsize = 1;
		tmp.columns = 1;
		auto int64_type = type_to_glsl(tmp);

		if (splat)
		{
			res += convert_to_string(c.scalar_i64(vector, 0), int64_type, backend.long_long_literal_suffix);
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
					res += convert_to_string(c.scalar_i64(vector, i), int64_type, backend.long_long_literal_suffix);

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;
	}

	case SPIRType::UInt64:
		if (splat)
		{
			res += convert_to_string(c.scalar_u64(vector, 0));
			if (backend.long_long_literal_suffix)
				res += "ull";
			else
				res += "ul";
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
				{
					res += convert_to_string(c.scalar_u64(vector, i));
					if (backend.long_long_literal_suffix)
						res += "ull";
					else
						res += "ul";
				}

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::UInt:
		if (splat)
		{
			res += convert_to_string(c.scalar(vector, 0));
			if (is_legacy())
			{
				// Fake unsigned constant literals with signed ones if possible.
				// Things like array sizes, etc, tend to be unsigned even though they could just as easily be signed.
				if (c.scalar_i32(vector, 0) < 0)
					SPIRV_CROSS_THROW("Tried to convert uint literal into int, but this made the literal negative.");
			}
			else if (backend.uint32_t_literal_suffix)
				res += "u";
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
				{
					res += convert_to_string(c.scalar(vector, i));
					if (is_legacy())
					{
						// Fake unsigned constant literals with signed ones if possible.
						// Things like array sizes, etc, tend to be unsigned even though they could just as easily be signed.
						if (c.scalar_i32(vector, i) < 0)
							SPIRV_CROSS_THROW("Tried to convert uint literal into int, but this made "
							                  "the literal negative.");
					}
					else if (backend.uint32_t_literal_suffix)
						res += "u";
				}

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::Int:
		if (splat)
			res += convert_to_string(c.scalar_i32(vector, 0));
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
					res += convert_to_string(c.scalar_i32(vector, i));
				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::UShort:
		if (splat)
		{
			res += convert_to_string(c.scalar(vector, 0));
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
				{
					if (*backend.uint16_t_literal_suffix)
					{
						res += convert_to_string(c.scalar_u16(vector, i));
						res += backend.uint16_t_literal_suffix;
					}
					else
					{
						// If backend doesn't have a literal suffix, we need to value cast.
						res += type_to_glsl(scalar_type);
						res += "(";
						res += convert_to_string(c.scalar_u16(vector, i));
						res += ")";
					}
				}

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::Short:
		if (splat)
		{
			res += convert_to_string(c.scalar_i16(vector, 0));
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
				{
					if (*backend.int16_t_literal_suffix)
					{
						res += convert_to_string(c.scalar_i16(vector, i));
						res += backend.int16_t_literal_suffix;
					}
					else
					{
						// If backend doesn't have a literal suffix, we need to value cast.
						res += type_to_glsl(scalar_type);
						res += "(";
						res += convert_to_string(c.scalar_i16(vector, i));
						res += ")";
					}
				}

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::UByte:
		if (splat)
		{
			res += convert_to_string(c.scalar_u8(vector, 0));
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
				{
					res += type_to_glsl(scalar_type);
					res += "(";
					res += convert_to_string(c.scalar_u8(vector, i));
					res += ")";
				}

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::SByte:
		if (splat)
		{
			res += convert_to_string(c.scalar_i8(vector, 0));
		}
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
				{
					res += type_to_glsl(scalar_type);
					res += "(";
					res += convert_to_string(c.scalar_i8(vector, i));
					res += ")";
				}

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	case SPIRType::Boolean:
		if (splat)
			res += c.scalar(vector, 0) ? "true" : "false";
		else
		{
			for (uint32_t i = 0; i < c.vector_size(); i++)
			{
				if (c.vector_size() > 1 && c.specialization_constant_id(vector, i) != 0)
					res += to_expression(c.specialization_constant_id(vector, i));
				else
					res += c.scalar(vector, i) ? "true" : "false";

				if (i + 1 < c.vector_size())
					res += ", ";
			}
		}
		break;

	default:
		SPIRV_CROSS_THROW("Invalid constant expression basetype.");
	}

	if (c.vector_size() > 1 && !swizzle_splat)
		res += ")";

	return res;
}

string CompilerHLSL::convert_float_to_string(const SPIRConstant &c, uint32_t col, uint32_t row)
{
	string res;
	float float_value = c.scalar_f32(col, row);

	if (std::isnan(float_value) || std::isinf(float_value))
	{
		// Use special representation.
		if (!is_legacy())
		{
			SPIRType out_type;
			SPIRType in_type;
			out_type.basetype = SPIRType::Float;
			in_type.basetype = SPIRType::UInt;
			out_type.vecsize = 1;
			in_type.vecsize = 1;
			out_type.width = 32;
			in_type.width = 32;

			char print_buffer[32];
#ifdef _WIN32
			sprintf_s(print_buffer, "0x%xu", c.scalar(col, row));
#else
			snprintf(print_buffer, sizeof(print_buffer), "0x%xu", c.scalar(col, row));
#endif

			const char *comment = "inf";
			if (float_value == -numeric_limits<float>::infinity())
				comment = "-inf";
			else if (std::isnan(float_value))
				comment = "nan";
			res = join(bitcast_glsl_op(out_type, in_type), "(", print_buffer, " /* ", comment, " */)");
		}
		else
		{
			if (float_value == numeric_limits<float>::infinity())
			{
				if (backend.float_literal_suffix)
					res = "(1.0f / 0.0f)";
				else
					res = "(1.0 / 0.0)";
			}
			else if (float_value == -numeric_limits<float>::infinity())
			{
				if (backend.float_literal_suffix)
					res = "(-1.0f / 0.0f)";
				else
					res = "(-1.0 / 0.0)";
			}
			else if (std::isnan(float_value))
			{
				if (backend.float_literal_suffix)
					res = "(0.0f / 0.0f)";
				else
					res = "(0.0 / 0.0)";
			}
			else
				SPIRV_CROSS_THROW("Cannot represent non-finite floating point constant.");
		}
	}
	else
	{
		res = convert_to_string(float_value, current_locale_radix_character);
		if (backend.float_literal_suffix)
			res += "f";
	}

	return res;
}

void CompilerHLSL::handle_invalid_expression(uint32_t id)
{
	// We tried to read an invalidated expression.
	// This means we need another pass at compilation, but next time,
	// force temporary variables so that they cannot be invalidated.
	force_temporary_and_recompile(id);

	// If the invalid expression happened as a result of a CompositeInsert
	// overwrite, we must block this from happening next iteration.
	if (composite_insert_overwritten.count(id))
		block_composite_insert_overwrite.insert(id);
}

// Sometimes we proactively enclosed an expression where it turns out we might have not needed it after all.
void CompilerHLSL::strip_enclosed_expression(string &expr)
{
	if (expr.size() < 2 || expr.front() != '(' || expr.back() != ')')
		return;

	// Have to make sure that our first and last parens actually enclose everything inside it.
	uint32_t paren_count = 0;
	for (auto &c : expr)
	{
		if (c == '(')
			paren_count++;
		else if (c == ')')
		{
			paren_count--;

			// If we hit 0 and this is not the final char, our first and final parens actually don't
			// enclose the expression, and we cannot strip, e.g.: (a + b) * (c + d).
			if (paren_count == 0 && &c != &expr.back())
				return;
		}
	}
	expr.erase(expr.size() - 1, 1);
	expr.erase(begin(expr));
}

bool CompilerHLSL::to_trivial_mix_op(const SPIRType &type, string &op, uint32_t left, uint32_t right, uint32_t lerp)
{
	auto *cleft = maybe_get<SPIRConstant>(left);
	auto *cright = maybe_get<SPIRConstant>(right);
	auto &lerptype = expression_type(lerp);

	// If our targets aren't constants, we cannot use construction.
	if (!cleft || !cright)
		return false;

	// If our targets are spec constants, we cannot use construction.
	if (cleft->specialization || cright->specialization)
		return false;

	auto &value_type = get<SPIRType>(cleft->constant_type);

	if (lerptype.basetype != SPIRType::Boolean)
		return false;
	if (value_type.basetype == SPIRType::Struct || is_array(value_type))
		return false;
	if (!backend.use_constructor_splatting && value_type.vecsize != lerptype.vecsize)
		return false;

	// Only valid way in SPIR-V 1.4 to use matrices in select is a scalar select.
	// matrix(scalar) constructor fills in diagnonals, so gets messy very quickly.
	// Just avoid this case.
	if (value_type.columns > 1)
		return false;

	// If our bool selects between 0 and 1, we can cast from bool instead, making our trivial constructor.
	bool ret = true;
	for (uint32_t row = 0; ret && row < value_type.vecsize; row++)
	{
		switch (type.basetype)
		{
		case SPIRType::Short:
		case SPIRType::UShort:
			ret = cleft->scalar_u16(0, row) == 0 && cright->scalar_u16(0, row) == 1;
			break;

		case SPIRType::Int:
		case SPIRType::UInt:
			ret = cleft->scalar(0, row) == 0 && cright->scalar(0, row) == 1;
			break;

		case SPIRType::Half:
			ret = cleft->scalar_f16(0, row) == 0.0f && cright->scalar_f16(0, row) == 1.0f;
			break;

		case SPIRType::Float:
			ret = cleft->scalar_f32(0, row) == 0.0f && cright->scalar_f32(0, row) == 1.0f;
			break;

		case SPIRType::Double:
			ret = cleft->scalar_f64(0, row) == 0.0 && cright->scalar_f64(0, row) == 1.0;
			break;

		case SPIRType::Int64:
		case SPIRType::UInt64:
			ret = cleft->scalar_u64(0, row) == 0 && cright->scalar_u64(0, row) == 1;
			break;

		default:
			ret = false;
			break;
		}
	}

	if (ret)
		op = type_to_glsl_constructor(type);
	return ret;
}

string CompilerHLSL::to_ternary_expression(const SPIRType &restype, uint32_t select, uint32_t true_value,
                                           uint32_t false_value)
{
	string expr;
	auto &lerptype = expression_type(select);

	if (lerptype.vecsize == 1)
		expr = join(to_enclosed_expression(select), " ? ", to_enclosed_pointer_expression(true_value), " : ",
		            to_enclosed_pointer_expression(false_value));
	else
	{
		auto swiz = [this](uint32_t expression, uint32_t i) { return to_extract_component_expression(expression, i); };

		expr = type_to_glsl_constructor(restype);
		expr += "(";
		for (uint32_t i = 0; i < restype.vecsize; i++)
		{
			expr += swiz(select, i);
			expr += " ? ";
			expr += swiz(true_value, i);
			expr += " : ";
			expr += swiz(false_value, i);
			if (i + 1 < restype.vecsize)
				expr += ", ";
		}
		expr += ")";
	}

	return expr;
}

string CompilerHLSL::to_enclosed_pointer_expression(uint32_t id, bool register_expression_read)
{
	auto &type = expression_type(id);
	if (type.pointer && expression_is_lvalue(id) && !should_dereference(id))
		return address_of_expression(to_enclosed_expression(id, register_expression_read));
	else
		return to_enclosed_unpacked_expression(id, register_expression_read);
}

SPIRType CompilerHLSL::binary_op_bitcast_helper(string &cast_op0, string &cast_op1, SPIRType::BaseType &input_type,
                                                uint32_t op0, uint32_t op1, bool skip_cast_if_equal_type)
{
	auto &type0 = expression_type(op0);
	auto &type1 = expression_type(op1);

	// We have to bitcast if our inputs are of different type, or if our types are not equal to expected inputs.
	// For some functions like OpIEqual and INotEqual, we don't care if inputs are of different types than expected
	// since equality test is exactly the same.
	bool cast = (type0.basetype != type1.basetype) || (!skip_cast_if_equal_type && type0.basetype != input_type);

	// Create a fake type so we can bitcast to it.
	// We only deal with regular arithmetic types here like int, uints and so on.
	SPIRType expected_type;
	expected_type.basetype = input_type;
	expected_type.vecsize = type0.vecsize;
	expected_type.columns = type0.columns;
	expected_type.width = type0.width;

	if (cast)
	{
		cast_op0 = bitcast_glsl(expected_type, op0);
		cast_op1 = bitcast_glsl(expected_type, op1);
	}
	else
	{
		// If we don't cast, our actual input type is that of the first (or second) argument.
		cast_op0 = to_enclosed_unpacked_expression(op0);
		cast_op1 = to_enclosed_unpacked_expression(op1);
		input_type = type0.basetype;
	}

	return expected_type;
}

bool CompilerHLSL::type_is_empty(const SPIRType &type)
{
	return type.basetype == SPIRType::Struct && type.member_types.empty();
}

void CompilerHLSL::emit_struct_padding_target(const SPIRType &)
{
}

string CompilerHLSL::variable_decl_function_local(SPIRVariable &var)
{
	// These variables are always function local,
	// so make sure we emit the variable without storage qualifiers.
	// Some backends will inject custom variables locally in a function
	// with a storage qualifier which is not function-local.
	auto old_storage = var.storage;
	var.storage = StorageClassFunction;
	auto expr = variable_decl(var);
	var.storage = old_storage;
	return expr;
}

void CompilerHLSL::emit_variable_temporary_copies(const SPIRVariable &var)
{
	// Ensure that we declare phi-variable copies even if the original declaration isn't deferred
	if (var.allocate_temporary_copy && !flushed_phi_variables.count(var.self))
	{
		auto &type = get<SPIRType>(var.basetype);
		auto &flags = get_decoration_bitset(var.self);
		statement(flags_to_qualifiers_glsl(type, flags), variable_decl(type, join("_", var.self, "_copy")), ";");
		flushed_phi_variables.insert(var.self);
	}
}

string CompilerHLSL::unpack_expression_type(string expr_str, const SPIRType &, uint32_t, bool, bool)
{
	return expr_str;
}

uint32_t CompilerHLSL::type_to_packed_alignment(const SPIRType &type, const Bitset &flags,
                                                BufferPackingStandard packing)
{
	// If using PhysicalStorageBufferEXT storage class, this is a pointer,
	// and is 64-bit.
	if (type_is_top_level_physical_pointer(type))
	{
		if (!type.pointer)
			SPIRV_CROSS_THROW("Types in PhysicalStorageBufferEXT must be pointers.");

		if (ir.addressing_model == AddressingModelPhysicalStorageBuffer64EXT)
		{
			if (packing_is_vec4_padded(packing) && type_is_array_of_pointers(type))
				return 16;
			else
				return 8;
		}
		else
			SPIRV_CROSS_THROW("AddressingModelPhysicalStorageBuffer64EXT must be used for PhysicalStorageBufferEXT.");
	}
	else if (type_is_top_level_array(type))
	{
		uint32_t minimum_alignment = 1;
		if (packing_is_vec4_padded(packing))
			minimum_alignment = 16;

		auto *tmp = &get<SPIRType>(type.parent_type);
		while (!tmp->array.empty())
			tmp = &get<SPIRType>(tmp->parent_type);

		// Get the alignment of the base type, then maybe round up.
		return max(minimum_alignment, type_to_packed_alignment(*tmp, flags, packing));
	}

	if (type.basetype == SPIRType::Struct)
	{
		// Rule 9. Structs alignments are maximum alignment of its members.
		uint32_t alignment = 1;
		for (uint32_t i = 0; i < type.member_types.size(); i++)
		{
			auto member_flags = ir.meta[type.self].members[i].decoration_flags;
			alignment =
			    max(alignment, type_to_packed_alignment(get<SPIRType>(type.member_types[i]), member_flags, packing));
		}

		// In std140, struct alignment is rounded up to 16.
		if (packing_is_vec4_padded(packing))
			alignment = max<uint32_t>(alignment, 16u);

		return alignment;
	}
	else
	{
		const uint32_t base_alignment = type_to_packed_base_size(type, packing);

		// Alignment requirement for scalar block layout is always the alignment for the most basic component.
		if (packing_is_scalar(packing))
			return base_alignment;

		// Vectors are *not* aligned in HLSL, but there's an extra rule where vectors cannot straddle
		// a vec4, this is handled outside since that part knows our current offset.
		if (type.columns == 1 && packing_is_hlsl(packing))
			return base_alignment;

		// From 7.6.2.2 in GL 4.5 core spec.
		// Rule 1
		if (type.vecsize == 1 && type.columns == 1)
			return base_alignment;

		// Rule 2
		if ((type.vecsize == 2 || type.vecsize == 4) && type.columns == 1)
			return type.vecsize * base_alignment;

		// Rule 3
		if (type.vecsize == 3 && type.columns == 1)
			return 4 * base_alignment;

		// Rule 4 implied. Alignment does not change in std430.

		// Rule 5. Column-major matrices are stored as arrays of
		// vectors.
		if (flags.get(DecorationColMajor) && type.columns > 1)
		{
			if (packing_is_vec4_padded(packing))
				return 4 * base_alignment;
			else if (type.vecsize == 3)
				return 4 * base_alignment;
			else
				return type.vecsize * base_alignment;
		}

		// Rule 6 implied.

		// Rule 7.
		if (flags.get(DecorationRowMajor) && type.vecsize > 1)
		{
			if (packing_is_vec4_padded(packing))
				return 4 * base_alignment;
			else if (type.columns == 3)
				return 4 * base_alignment;
			else
				return type.columns * base_alignment;
		}

		// Rule 8 implied.
	}

	SPIRV_CROSS_THROW("Did not find suitable rule for type. Bogus decorations?");
}

uint32_t CompilerHLSL::type_to_packed_base_size(const SPIRType &type, BufferPackingStandard)
{
	switch (type.basetype)
	{
	case SPIRType::Double:
	case SPIRType::Int64:
	case SPIRType::UInt64:
		return 8;
	case SPIRType::Float:
	case SPIRType::Int:
	case SPIRType::UInt:
		return 4;
	case SPIRType::Half:
	case SPIRType::Short:
	case SPIRType::UShort:
		return 2;
	case SPIRType::SByte:
	case SPIRType::UByte:
		return 1;

	default:
		SPIRV_CROSS_THROW("Unrecognized type in type_to_packed_base_size.");
	}
}

uint32_t CompilerHLSL::to_array_size_literal(const SPIRType &type) const
{
	return to_array_size_literal(type, uint32_t(type.array.size() - 1));
}

uint32_t CompilerHLSL::to_array_size_literal(const SPIRType &type, uint32_t index) const
{
	assert(type.array.size() == type.array_size_literal.size());

	if (type.array_size_literal[index])
	{
		return type.array[index];
	}
	else
	{
		// Use the default spec constant value.
		// This is the best we can do.
		return evaluate_constant_u32(type.array[index]);
	}
}

uint32_t CompilerHLSL::type_to_packed_array_stride(const SPIRType &type, const Bitset &flags,
                                                   BufferPackingStandard packing)
{
	// Array stride is equal to aligned size of the underlying type.
	uint32_t parent = type.parent_type;
	assert(parent);

	auto &tmp = get<SPIRType>(parent);

	uint32_t size = type_to_packed_size(tmp, flags, packing);
	uint32_t alignment = type_to_packed_alignment(type, flags, packing);
	return (size + alignment - 1) & ~(alignment - 1);
}

uint32_t CompilerHLSL::type_to_packed_size(const SPIRType &type, const Bitset &flags, BufferPackingStandard packing)
{
	// If using PhysicalStorageBufferEXT storage class, this is a pointer,
	// and is 64-bit.
	if (type_is_top_level_physical_pointer(type))
	{
		if (!type.pointer)
			SPIRV_CROSS_THROW("Types in PhysicalStorageBufferEXT must be pointers.");

		if (ir.addressing_model == AddressingModelPhysicalStorageBuffer64EXT)
			return 8;
		else
			SPIRV_CROSS_THROW("AddressingModelPhysicalStorageBuffer64EXT must be used for PhysicalStorageBufferEXT.");
	}
	else if (type_is_top_level_array(type))
	{
		uint32_t packed_size = to_array_size_literal(type) * type_to_packed_array_stride(type, flags, packing);

		// For arrays of vectors and matrices in HLSL, the last element has a size which depends on its vector size,
		// so that it is possible to pack other vectors into the last element.
		if (packing_is_hlsl(packing) && type.basetype != SPIRType::Struct)
			packed_size -= (4 - type.vecsize) * (type.width / 8);

		return packed_size;
	}

	uint32_t size = 0;

	if (type.basetype == SPIRType::Struct)
	{
		uint32_t pad_alignment = 1;

		for (uint32_t i = 0; i < type.member_types.size(); i++)
		{
			auto member_flags = ir.meta[type.self].members[i].decoration_flags;
			auto &member_type = get<SPIRType>(type.member_types[i]);

			uint32_t packed_alignment = type_to_packed_alignment(member_type, member_flags, packing);
			uint32_t alignment = max(packed_alignment, pad_alignment);

			// The next member following a struct member is aligned to the base alignment of the struct that came before.
			// GL 4.5 spec, 7.6.2.2.
			if (member_type.basetype == SPIRType::Struct)
				pad_alignment = packed_alignment;
			else
				pad_alignment = 1;

			size = (size + alignment - 1) & ~(alignment - 1);
			size += type_to_packed_size(member_type, member_flags, packing);
		}
	}
	else
	{
		const uint32_t base_alignment = type_to_packed_base_size(type, packing);

		if (packing_is_scalar(packing))
		{
			size = type.vecsize * type.columns * base_alignment;
		}
		else
		{
			if (type.columns == 1)
				size = type.vecsize * base_alignment;

			if (flags.get(DecorationColMajor) && type.columns > 1)
			{
				if (packing_is_vec4_padded(packing))
					size = type.columns * 4 * base_alignment;
				else if (type.vecsize == 3)
					size = type.columns * 4 * base_alignment;
				else
					size = type.columns * type.vecsize * base_alignment;
			}

			if (flags.get(DecorationRowMajor) && type.vecsize > 1)
			{
				if (packing_is_vec4_padded(packing))
					size = type.vecsize * 4 * base_alignment;
				else if (type.columns == 3)
					size = type.vecsize * 4 * base_alignment;
				else
					size = type.vecsize * type.columns * base_alignment;
			}

			// For matrices in HLSL, the last element has a size which depends on its vector size,
			// so that it is possible to pack other vectors into the last element.
			if (packing_is_hlsl(packing) && type.columns > 1)
				size -= (4 - type.vecsize) * (type.width / 8);
		}
	}

	return size;
}

string CompilerHLSL::declare_temporary(uint32_t result_type, uint32_t result_id)
{
	auto &type = get<SPIRType>(result_type);

	// If we're declaring temporaries inside continue blocks,
	// we must declare the temporary in the loop header so that the continue block can avoid declaring new variables.
	if (!block_temporary_hoisting && current_continue_block && !hoisted_temporaries.count(result_id))
	{
		auto &header = get<SPIRBlock>(current_continue_block->loop_dominator);
		if (find_if(begin(header.declare_temporary), end(header.declare_temporary),
		            [result_type, result_id](const pair<uint32_t, uint32_t> &tmp) {
			            return tmp.first == result_type && tmp.second == result_id;
		            }) == end(header.declare_temporary))
		{
			header.declare_temporary.emplace_back(result_type, result_id);
			hoisted_temporaries.insert(result_id);
			force_recompile_guarantee_forward_progress();
		}

		return join(to_name(result_id), " = ");
	}
	else if (hoisted_temporaries.count(result_id))
	{
		// The temporary has already been declared earlier, so just "declare" the temporary by writing to it.
		return join(to_name(result_id), " = ");
	}
	else
	{
		// The result_id has not been made into an expression yet, so use flags interface.
		add_local_variable_name(result_id);
		auto &flags = get_decoration_bitset(result_id);
		return join(flags_to_qualifiers_glsl(type, flags), variable_decl(type, to_name(result_id)), " = ");
	}
}

bool CompilerHLSL::expression_suppresses_usage_tracking(uint32_t id) const
{
	return suppressed_usage_tracking.count(id) != 0;
}

bool CompilerHLSL::expression_read_implies_multiple_reads(uint32_t id) const
{
	auto *expr = maybe_get<SPIRExpression>(id);
	if (!expr)
		return false;

	// If we're emitting code at a deeper loop level than when we emitted the expression,
	// we're probably reading the same expression over and over.
	return current_loop_level > expr->emitted_loop_level;
}

void CompilerHLSL::force_temporary_and_recompile(uint32_t id)
{
	auto res = forced_temporaries.insert(id);

	// Forcing new temporaries guarantees forward progress.
	if (res.second)
		force_recompile_guarantee_forward_progress();
	else
		force_recompile();
}

bool CompilerHLSL::needs_enclose_expression(const std::string &expr)
{
	bool need_parens = false;

	// If the expression starts with a unary we need to enclose to deal with cases where we have back-to-back
	// unary expressions.
	if (!expr.empty())
	{
		auto c = expr.front();
		if (c == '-' || c == '+' || c == '!' || c == '~' || c == '&' || c == '*')
			need_parens = true;
	}

	if (!need_parens)
	{
		uint32_t paren_count = 0;
		for (auto c : expr)
		{
			if (c == '(' || c == '[')
				paren_count++;
			else if (c == ')' || c == ']')
			{
				assert(paren_count);
				paren_count--;
			}
			else if (c == ' ' && paren_count == 0)
			{
				need_parens = true;
				break;
			}
		}
		assert(paren_count == 0);
	}

	return need_parens;
}

bool CompilerHLSL::should_dereference(uint32_t id)
{
	const auto &type = expression_type(id);
	// Non-pointer expressions don't need to be dereferenced.
	if (!type.pointer)
		return false;

	// Handles shouldn't be dereferenced either.
	if (!expression_is_lvalue(id))
		return false;

	// If id is a variable but not a phi variable, we should not dereference it.
	if (auto *var = maybe_get<SPIRVariable>(id))
		return var->phi_variable;

	if (auto *expr = maybe_get<SPIRExpression>(id))
	{
		// If id is an access chain, we should not dereference it.
		if (expr->access_chain)
			return false;

		// If id is a forwarded copy of a variable pointer, we should not dereference it.
		SPIRVariable *var = nullptr;
		while (expr->loaded_from && expression_is_forwarded(expr->self))
		{
			auto &src_type = expression_type(expr->loaded_from);
			// To be a copy, the pointer and its source expression must be the
			// same type. Can't check type.self, because for some reason that's
			// usually the base type with pointers stripped off. This check is
			// complex enough that I've hoisted it out of the while condition.
			if (src_type.pointer != type.pointer || src_type.pointer_depth != type.pointer_depth ||
			    src_type.parent_type != type.parent_type)
				break;
			if ((var = maybe_get<SPIRVariable>(expr->loaded_from)))
				break;
			if (!(expr = maybe_get<SPIRExpression>(expr->loaded_from)))
				break;
		}

		return !var || var->phi_variable;
	}

	// Otherwise, we should dereference this pointer expression.
	return true;
}



// Checks whether the ID is a row_major matrix that requires conversion before use
bool CompilerHLSL::is_non_native_row_major_matrix(uint32_t id)
{
	// Natively supported row-major matrices do not need to be converted.
	// Legacy targets do not support row major.
	if (backend.native_row_major_matrix && !is_legacy())
		return false;

	auto *e = maybe_get<SPIRExpression>(id);
	if (e)
		return e->need_transpose;
	else
		return has_decoration(id, DecorationRowMajor);
}

void CompilerHLSL::access_chain_internal_append_index(std::string &expr, uint32_t /*base*/, const SPIRType * /*type*/,
                                                      AccessChainFlags flags, bool &access_chain_is_arrayed,
                                                      uint32_t index)
{
	bool index_is_literal = (flags & ACCESS_CHAIN_INDEX_IS_LITERAL_BIT) != 0;
	bool ptr_chain = (flags & ACCESS_CHAIN_PTR_CHAIN_BIT) != 0;
	bool register_expression_read = (flags & ACCESS_CHAIN_SKIP_REGISTER_EXPRESSION_READ_BIT) == 0;

	string idx_expr = index_is_literal ? convert_to_string(index) : to_unpacked_expression(index, register_expression_read);

	// For the case where the base of an OpPtrAccessChain already ends in [n],
	// we need to use the index as an offset to the existing index, otherwise,
	// we can just use the index directly.
	if (ptr_chain && access_chain_is_arrayed)
	{
		size_t split_pos = expr.find_last_of(']');
		string expr_front = expr.substr(0, split_pos);
		string expr_back = expr.substr(split_pos);
		expr = expr_front + " + " +  enclose_expression(idx_expr) + expr_back;
	}
	else
	{
		expr += "[";
		expr += idx_expr;
		expr += "]";
	}
}

void CompilerHLSL::check_physical_type_cast(std::string &, const SPIRType *, uint32_t)
{
}

bool CompilerHLSL::access_chain_needs_stage_io_builtin_translation(uint32_t)
{
	return true;
}

string CompilerHLSL::to_member_reference(uint32_t, const SPIRType &type, uint32_t index, bool)
{
	return join(".", to_member_name(type, index));
}

// Checks whether the member is in packed data type, that might need to be unpacked.
bool CompilerHLSL::member_is_packed_physical_type(const SPIRType &type, uint32_t index) const
{
	return has_extended_member_decoration(type.self, index, SPIRVCrossDecorationPhysicalTypePacked);
}

// Checks if we need to remap physical type IDs when declaring the type in a buffer.
bool CompilerHLSL::member_is_remapped_physical_type(const SPIRType &type, uint32_t index) const
{
	return has_extended_member_decoration(type.self, index, SPIRVCrossDecorationPhysicalTypeID);
}

// Checks whether the member is a row_major matrix that requires conversion before use
bool CompilerHLSL::member_is_non_native_row_major_matrix(const SPIRType &type, uint32_t index)
{
	// Natively supported row-major matrices do not need to be converted.
	if (backend.native_row_major_matrix && !is_legacy())
		return false;

	// Non-matrix or column-major matrix types do not need to be converted.
	if (!has_member_decoration(type.self, index, DecorationRowMajor))
		return false;

	// Only square row-major matrices can be converted at this time.
	// Converting non-square matrices will require defining custom GLSL function that
	// swaps matrix elements while retaining the original dimensional form of the matrix.
	const auto mbr_type = get<SPIRType>(type.member_types[index]);
	if (mbr_type.columns != mbr_type.vecsize)
		SPIRV_CROSS_THROW("Row-major matrices must be square on this platform.");

	return true;
}

void CompilerHLSL::prepare_access_chain_for_scalar_access(std::string &, const SPIRType &, spv::StorageClass, bool &)
{
}

StorageClass CompilerHLSL::get_expression_effective_storage_class(uint32_t ptr)
{
	auto *var = maybe_get_backing_variable(ptr);

	// If the expression has been lowered to a temporary, we need to use the Generic storage class.
	// We're looking for the effective storage class of a given expression.
	// An access chain or forwarded OpLoads from such access chains
	// will generally have the storage class of the underlying variable, but if the load was not forwarded
	// we have lost any address space qualifiers.
	bool forced_temporary = ir.ids[ptr].get_type() == TypeExpression && !get<SPIRExpression>(ptr).access_chain &&
	                        (forced_temporaries.count(ptr) != 0 || forwarded_temporaries.count(ptr) == 0);

	if (var && !forced_temporary)
	{
		if (variable_decl_is_remapped_storage(*var, StorageClassWorkgroup))
			return StorageClassWorkgroup;
		if (variable_decl_is_remapped_storage(*var, StorageClassStorageBuffer))
			return StorageClassStorageBuffer;

		// Normalize SSBOs to StorageBuffer here.
		if (var->storage == StorageClassUniform &&
		    has_decoration(get<SPIRType>(var->basetype).self, DecorationBufferBlock))
			return StorageClassStorageBuffer;
		else
			return var->storage;
	}
	else
		return expression_type(ptr).storage;
}

std::string CompilerHLSL::to_flattened_access_chain_expression(uint32_t id)
{
	// Do not use to_expression as that will unflatten access chains.
	string basename;
	if (const auto *var = maybe_get<SPIRVariable>(id))
		basename = to_name(var->self);
	else if (const auto *expr = maybe_get<SPIRExpression>(id))
		basename = expr->expression;
	else
		basename = to_expression(id);

	return basename;
}

string CompilerHLSL::to_enclosed_unpacked_expression(uint32_t id, bool register_expression_read)
{
	return enclose_expression(to_unpacked_expression(id, register_expression_read));
}

string CompilerHLSL::CompilerGLSL_to_initializer_expression(const SPIRVariable &var)
{
	return to_unpacked_expression(var.initializer);
}

string CompilerHLSL::CompilerGLSL_builtin_to_glsl(BuiltIn builtin, StorageClass storage)
{
	switch (builtin)
	{
	case BuiltInPosition:
		return "gl_Position";
	case BuiltInPointSize:
		return "gl_PointSize";
	case BuiltInClipDistance:
	{
		if (options.es)
			require_extension_internal("GL_EXT_clip_cull_distance");
		return "gl_ClipDistance";
	}
	case BuiltInCullDistance:
	{
		if (options.es)
			require_extension_internal("GL_EXT_clip_cull_distance");
		return "gl_CullDistance";
	}
	case BuiltInVertexId:
		if (options.vulkan_semantics)
			SPIRV_CROSS_THROW("Cannot implement gl_VertexID in Vulkan GLSL. This shader was created "
			                  "with GL semantics.");
		return "gl_VertexID";
	case BuiltInInstanceId:
		if (options.vulkan_semantics)
		{
			auto model = get_entry_point().model;
			switch (model)
			{
			case spv::ExecutionModelIntersectionKHR:
			case spv::ExecutionModelAnyHitKHR:
			case spv::ExecutionModelClosestHitKHR:
				// gl_InstanceID is allowed in these shaders.
				break;

			default:
				SPIRV_CROSS_THROW("Cannot implement gl_InstanceID in Vulkan GLSL. This shader was "
				                  "created with GL semantics.");
			}
		}
		if (!options.es && options.version < 140)
		{
			require_extension_internal("GL_ARB_draw_instanced");
		}
		return "gl_InstanceID";
	case BuiltInVertexIndex:
		if (options.vulkan_semantics)
			return "gl_VertexIndex";
		else
			return "gl_VertexID"; // gl_VertexID already has the base offset applied.
	case BuiltInInstanceIndex:
		if (options.vulkan_semantics)
			return "gl_InstanceIndex";

		if (!options.es && options.version < 140)
		{
			require_extension_internal("GL_ARB_draw_instanced");
		}

		if (options.vertex.support_nonzero_base_instance)
		{
			if (!options.vulkan_semantics)
			{
				// This is a soft-enable. We will opt-in to using gl_BaseInstanceARB if supported.
				require_extension_internal("GL_ARB_shader_draw_parameters");
			}
			return "(gl_InstanceID + SPIRV_Cross_BaseInstance)"; // ... but not gl_InstanceID.
		}
		else
			return "gl_InstanceID";
	case BuiltInPrimitiveId:
		if (storage == StorageClassInput && get_entry_point().model == ExecutionModelGeometry)
			return "gl_PrimitiveIDIn";
		else
			return "gl_PrimitiveID";
	case BuiltInInvocationId:
		return "gl_InvocationID";
	case BuiltInLayer:
		return "gl_Layer";
	case BuiltInViewportIndex:
		return "gl_ViewportIndex";
	case BuiltInTessLevelOuter:
		return "gl_TessLevelOuter";
	case BuiltInTessLevelInner:
		return "gl_TessLevelInner";
	case BuiltInTessCoord:
		return "gl_TessCoord";
	case BuiltInFragCoord:
		return "gl_FragCoord";
	case BuiltInPointCoord:
		return "gl_PointCoord";
	case BuiltInFrontFacing:
		return "gl_FrontFacing";
	case BuiltInFragDepth:
		return "gl_FragDepth";
	case BuiltInNumWorkgroups:
		return "gl_NumWorkGroups";
	case BuiltInWorkgroupSize:
		return "gl_WorkGroupSize";
	case BuiltInWorkgroupId:
		return "gl_WorkGroupID";
	case BuiltInLocalInvocationId:
		return "gl_LocalInvocationID";
	case BuiltInGlobalInvocationId:
		return "gl_GlobalInvocationID";
	case BuiltInLocalInvocationIndex:
		return "gl_LocalInvocationIndex";
	case BuiltInHelperInvocation:
		return "gl_HelperInvocation";

	case BuiltInBaseVertex:
		if (options.es)
			SPIRV_CROSS_THROW("BaseVertex not supported in ES profile.");

		if (options.vulkan_semantics)
		{
			if (options.version < 460)
			{
				require_extension_internal("GL_ARB_shader_draw_parameters");
				return "gl_BaseVertexARB";
			}
			return "gl_BaseVertex";
		}
		// On regular GL, this is soft-enabled and we emit ifdefs in code.
		require_extension_internal("GL_ARB_shader_draw_parameters");
		return "SPIRV_Cross_BaseVertex";

	case BuiltInBaseInstance:
		if (options.es)
			SPIRV_CROSS_THROW("BaseInstance not supported in ES profile.");

		if (options.vulkan_semantics)
		{
			if (options.version < 460)
			{
				require_extension_internal("GL_ARB_shader_draw_parameters");
				return "gl_BaseInstanceARB";
			}
			return "gl_BaseInstance";
		}
		// On regular GL, this is soft-enabled and we emit ifdefs in code.
		require_extension_internal("GL_ARB_shader_draw_parameters");
		return "SPIRV_Cross_BaseInstance";

	case BuiltInDrawIndex:
		if (options.es)
			SPIRV_CROSS_THROW("DrawIndex not supported in ES profile.");

		if (options.vulkan_semantics)
		{
			if (options.version < 460)
			{
				require_extension_internal("GL_ARB_shader_draw_parameters");
				return "gl_DrawIDARB";
			}
			return "gl_DrawID";
		}
		// On regular GL, this is soft-enabled and we emit ifdefs in code.
		require_extension_internal("GL_ARB_shader_draw_parameters");
		return "gl_DrawIDARB";

	case BuiltInSampleId:
		if (is_legacy())
			SPIRV_CROSS_THROW("Sample variables not supported in legacy GLSL.");
		else if (options.es && options.version < 320)
			require_extension_internal("GL_OES_sample_variables");
		else if (!options.es && options.version < 400)
			require_extension_internal("GL_ARB_sample_shading");
		return "gl_SampleID";

	case BuiltInSampleMask:
		if (is_legacy())
			SPIRV_CROSS_THROW("Sample variables not supported in legacy GLSL.");
		else if (options.es && options.version < 320)
			require_extension_internal("GL_OES_sample_variables");
		else if (!options.es && options.version < 400)
			require_extension_internal("GL_ARB_sample_shading");

		if (storage == StorageClassInput)
			return "gl_SampleMaskIn";
		else
			return "gl_SampleMask";

	case BuiltInSamplePosition:
		if (is_legacy())
			SPIRV_CROSS_THROW("Sample variables not supported in legacy GLSL.");
		else if (options.es && options.version < 320)
			require_extension_internal("GL_OES_sample_variables");
		else if (!options.es && options.version < 400)
			require_extension_internal("GL_ARB_sample_shading");
		return "gl_SamplePosition";

	case BuiltInViewIndex:
		if (options.vulkan_semantics)
			return "gl_ViewIndex";
		else
			return "gl_ViewID_OVR";

	case BuiltInNumSubgroups:
		request_subgroup_feature(ShaderSubgroupSupportHelper::NumSubgroups);
		return "gl_NumSubgroups";

	case BuiltInSubgroupId:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupID);
		return "gl_SubgroupID";

	case BuiltInSubgroupSize:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupSize);
		return "gl_SubgroupSize";

	case BuiltInSubgroupLocalInvocationId:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupInvocationID);
		return "gl_SubgroupInvocationID";

	case BuiltInSubgroupEqMask:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupMask);
		return "gl_SubgroupEqMask";

	case BuiltInSubgroupGeMask:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupMask);
		return "gl_SubgroupGeMask";

	case BuiltInSubgroupGtMask:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupMask);
		return "gl_SubgroupGtMask";

	case BuiltInSubgroupLeMask:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupMask);
		return "gl_SubgroupLeMask";

	case BuiltInSubgroupLtMask:
		request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupMask);
		return "gl_SubgroupLtMask";

	case BuiltInLaunchIdKHR:
		return ray_tracing_is_khr ? "gl_LaunchIDEXT" : "gl_LaunchIDNV";
	case BuiltInLaunchSizeKHR:
		return ray_tracing_is_khr ? "gl_LaunchSizeEXT" : "gl_LaunchSizeNV";
	case BuiltInWorldRayOriginKHR:
		return ray_tracing_is_khr ? "gl_WorldRayOriginEXT" : "gl_WorldRayOriginNV";
	case BuiltInWorldRayDirectionKHR:
		return ray_tracing_is_khr ? "gl_WorldRayDirectionEXT" : "gl_WorldRayDirectionNV";
	case BuiltInObjectRayOriginKHR:
		return ray_tracing_is_khr ? "gl_ObjectRayOriginEXT" : "gl_ObjectRayOriginNV";
	case BuiltInObjectRayDirectionKHR:
		return ray_tracing_is_khr ? "gl_ObjectRayDirectionEXT" : "gl_ObjectRayDirectionNV";
	case BuiltInRayTminKHR:
		return ray_tracing_is_khr ? "gl_RayTminEXT" : "gl_RayTminNV";
	case BuiltInRayTmaxKHR:
		return ray_tracing_is_khr ? "gl_RayTmaxEXT" : "gl_RayTmaxNV";
	case BuiltInInstanceCustomIndexKHR:
		return ray_tracing_is_khr ? "gl_InstanceCustomIndexEXT" : "gl_InstanceCustomIndexNV";
	case BuiltInObjectToWorldKHR:
		return ray_tracing_is_khr ? "gl_ObjectToWorldEXT" : "gl_ObjectToWorldNV";
	case BuiltInWorldToObjectKHR:
		return ray_tracing_is_khr ? "gl_WorldToObjectEXT" : "gl_WorldToObjectNV";
	case BuiltInHitTNV:
		// gl_HitTEXT is an alias of RayTMax in KHR.
		return "gl_HitTNV";
	case BuiltInHitKindKHR:
		return ray_tracing_is_khr ? "gl_HitKindEXT" : "gl_HitKindNV";
	case BuiltInIncomingRayFlagsKHR:
		return ray_tracing_is_khr ? "gl_IncomingRayFlagsEXT" : "gl_IncomingRayFlagsNV";

	case BuiltInBaryCoordKHR:
	{
		if (options.es && options.version < 320)
			SPIRV_CROSS_THROW("gl_BaryCoordEXT requires ESSL 320.");
		else if (!options.es && options.version < 450)
			SPIRV_CROSS_THROW("gl_BaryCoordEXT requires GLSL 450.");

		if (barycentric_is_nv)
		{
			require_extension_internal("GL_NV_fragment_shader_barycentric");
			return "gl_BaryCoordNV";
		}
		else
		{
			require_extension_internal("GL_EXT_fragment_shader_barycentric");
			return "gl_BaryCoordEXT";
		}
	}

	case BuiltInBaryCoordNoPerspNV:
	{
		if (options.es && options.version < 320)
			SPIRV_CROSS_THROW("gl_BaryCoordNoPerspEXT requires ESSL 320.");
		else if (!options.es && options.version < 450)
			SPIRV_CROSS_THROW("gl_BaryCoordNoPerspEXT requires GLSL 450.");

		if (barycentric_is_nv)
		{
			require_extension_internal("GL_NV_fragment_shader_barycentric");
			return "gl_BaryCoordNoPerspNV";
		}
		else
		{
			require_extension_internal("GL_EXT_fragment_shader_barycentric");
			return "gl_BaryCoordNoPerspEXT";
		}
	}

	case BuiltInFragStencilRefEXT:
	{
		if (!options.es)
		{
			require_extension_internal("GL_ARB_shader_stencil_export");
			return "gl_FragStencilRefARB";
		}
		else
			SPIRV_CROSS_THROW("Stencil export not supported in GLES.");
	}

	case BuiltInPrimitiveShadingRateKHR:
	{
		if (!options.vulkan_semantics)
			SPIRV_CROSS_THROW("Can only use PrimitiveShadingRateKHR in Vulkan GLSL.");
		require_extension_internal("GL_EXT_fragment_shading_rate");
		return "gl_PrimitiveShadingRateEXT";
	}

	case BuiltInShadingRateKHR:
	{
		if (!options.vulkan_semantics)
			SPIRV_CROSS_THROW("Can only use ShadingRateKHR in Vulkan GLSL.");
		require_extension_internal("GL_EXT_fragment_shading_rate");
		return "gl_ShadingRateEXT";
	}

	case BuiltInDeviceIndex:
		if (!options.vulkan_semantics)
			SPIRV_CROSS_THROW("Need Vulkan semantics for device group support.");
		require_extension_internal("GL_EXT_device_group");
		return "gl_DeviceIndex";

	case BuiltInFullyCoveredEXT:
		if (!options.es)
			require_extension_internal("GL_NV_conservative_raster_underestimation");
		else
			SPIRV_CROSS_THROW("Need desktop GL to use GL_NV_conservative_raster_underestimation.");
		return "gl_FragFullyCoveredNV";

	case BuiltInPrimitiveTriangleIndicesEXT:
		return "gl_PrimitiveTriangleIndicesEXT";
	case BuiltInPrimitiveLineIndicesEXT:
		return "gl_PrimitiveLineIndicesEXT";
	case BuiltInPrimitivePointIndicesEXT:
		return "gl_PrimitivePointIndicesEXT";
	case BuiltInCullPrimitiveEXT:
		return "gl_CullPrimitiveEXT";

	default:
		return join("gl_BuiltIn_", convert_to_string(builtin));
	}
}

void CompilerHLSL::CompilerGLSL_replace_illegal_names(const unordered_set<string> &keywords)
{
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, const SPIRVariable &var) {
		if (is_hidden_variable(var))
			return;

		auto *meta = ir.find_meta(var.self);
		if (!meta)
			return;

		auto &m = meta->decoration;
		if (keywords.find(m.alias) != end(keywords))
			m.alias = join("_", m.alias);
	});

	ir.for_each_typed_id<SPIRFunction>([&](uint32_t, const SPIRFunction &func) {
		auto *meta = ir.find_meta(func.self);
		if (!meta)
			return;

		auto &m = meta->decoration;
		if (keywords.find(m.alias) != end(keywords))
			m.alias = join("_", m.alias);
	});

	ir.for_each_typed_id<SPIRType>([&](uint32_t, const SPIRType &type) {
		auto *meta = ir.find_meta(type.self);
		if (!meta)
			return;

		auto &m = meta->decoration;
		if (keywords.find(m.alias) != end(keywords))
			m.alias = join("_", m.alias);

		for (auto &memb : meta->members)
			if (keywords.find(memb.alias) != end(keywords))
				memb.alias = join("_", memb.alias);
	});
}

void CompilerHLSL::CompilerGLSL_replace_illegal_names()
{
	// clang-format off
	static const unordered_set<string> keywords = {
		"abs", "acos", "acosh", "all", "any", "asin", "asinh", "atan", "atanh",
		"atomicAdd", "atomicCompSwap", "atomicCounter", "atomicCounterDecrement", "atomicCounterIncrement",
		"atomicExchange", "atomicMax", "atomicMin", "atomicOr", "atomicXor",
		"bitCount", "bitfieldExtract", "bitfieldInsert", "bitfieldReverse",
		"ceil", "cos", "cosh", "cross", "degrees",
		"dFdx", "dFdxCoarse", "dFdxFine",
		"dFdy", "dFdyCoarse", "dFdyFine",
		"distance", "dot", "EmitStreamVertex", "EmitVertex", "EndPrimitive", "EndStreamPrimitive", "equal", "exp", "exp2",
		"faceforward", "findLSB", "findMSB", "float16BitsToInt16", "float16BitsToUint16", "floatBitsToInt", "floatBitsToUint", "floor", "fma", "fract",
		"frexp", "fwidth", "fwidthCoarse", "fwidthFine",
		"greaterThan", "greaterThanEqual", "groupMemoryBarrier",
		"imageAtomicAdd", "imageAtomicAnd", "imageAtomicCompSwap", "imageAtomicExchange", "imageAtomicMax", "imageAtomicMin", "imageAtomicOr", "imageAtomicXor",
		"imageLoad", "imageSamples", "imageSize", "imageStore", "imulExtended", "int16BitsToFloat16", "intBitsToFloat", "interpolateAtOffset", "interpolateAtCentroid", "interpolateAtSample",
		"inverse", "inversesqrt", "isinf", "isnan", "ldexp", "length", "lessThan", "lessThanEqual", "log", "log2",
		"matrixCompMult", "max", "memoryBarrier", "memoryBarrierAtomicCounter", "memoryBarrierBuffer", "memoryBarrierImage", "memoryBarrierShared",
		"min", "mix", "mod", "modf", "noise", "noise1", "noise2", "noise3", "noise4", "normalize", "not", "notEqual",
		"outerProduct", "packDouble2x32", "packHalf2x16", "packInt2x16", "packInt4x16", "packSnorm2x16", "packSnorm4x8",
		"packUint2x16", "packUint4x16", "packUnorm2x16", "packUnorm4x8", "pow",
		"radians", "reflect", "refract", "round", "roundEven", "sign", "sin", "sinh", "smoothstep", "sqrt", "step",
		"tan", "tanh", "texelFetch", "texelFetchOffset", "texture", "textureGather", "textureGatherOffset", "textureGatherOffsets",
		"textureGrad", "textureGradOffset", "textureLod", "textureLodOffset", "textureOffset", "textureProj", "textureProjGrad",
		"textureProjGradOffset", "textureProjLod", "textureProjLodOffset", "textureProjOffset", "textureQueryLevels", "textureQueryLod", "textureSamples", "textureSize",
		"transpose", "trunc", "uaddCarry", "uint16BitsToFloat16", "uintBitsToFloat", "umulExtended", "unpackDouble2x32", "unpackHalf2x16", "unpackInt2x16", "unpackInt4x16",
		"unpackSnorm2x16", "unpackSnorm4x8", "unpackUint2x16", "unpackUint4x16", "unpackUnorm2x16", "unpackUnorm4x8", "usubBorrow",

		"active", "asm", "atomic_uint", "attribute", "bool", "break", "buffer",
		"bvec2", "bvec3", "bvec4", "case", "cast", "centroid", "class", "coherent", "common", "const", "continue", "default", "discard",
		"dmat2", "dmat2x2", "dmat2x3", "dmat2x4", "dmat3", "dmat3x2", "dmat3x3", "dmat3x4", "dmat4", "dmat4x2", "dmat4x3", "dmat4x4",
		"do", "double", "dvec2", "dvec3", "dvec4", "else", "enum", "extern", "external", "false", "filter", "fixed", "flat", "float",
		"for", "fvec2", "fvec3", "fvec4", "goto", "half", "highp", "hvec2", "hvec3", "hvec4", "if", "iimage1D", "iimage1DArray",
		"iimage2D", "iimage2DArray", "iimage2DMS", "iimage2DMSArray", "iimage2DRect", "iimage3D", "iimageBuffer", "iimageCube",
		"iimageCubeArray", "image1D", "image1DArray", "image2D", "image2DArray", "image2DMS", "image2DMSArray", "image2DRect",
		"image3D", "imageBuffer", "imageCube", "imageCubeArray", "in", "inline", "inout", "input", "int", "interface", "invariant",
		"isampler1D", "isampler1DArray", "isampler2D", "isampler2DArray", "isampler2DMS", "isampler2DMSArray", "isampler2DRect",
		"isampler3D", "isamplerBuffer", "isamplerCube", "isamplerCubeArray", "ivec2", "ivec3", "ivec4", "layout", "long", "lowp",
		"mat2", "mat2x2", "mat2x3", "mat2x4", "mat3", "mat3x2", "mat3x3", "mat3x4", "mat4", "mat4x2", "mat4x3", "mat4x4", "mediump",
		"namespace", "noinline", "noperspective", "out", "output", "packed", "partition", "patch", "precise", "precision", "public", "readonly",
		"resource", "restrict", "return", "sample", "sampler1D", "sampler1DArray", "sampler1DArrayShadow",
		"sampler1DShadow", "sampler2D", "sampler2DArray", "sampler2DArrayShadow", "sampler2DMS", "sampler2DMSArray",
		"sampler2DRect", "sampler2DRectShadow", "sampler2DShadow", "sampler3D", "sampler3DRect", "samplerBuffer",
		"samplerCube", "samplerCubeArray", "samplerCubeArrayShadow", "samplerCubeShadow", "shared", "short", "sizeof", "smooth", "static",
		"struct", "subroutine", "superp", "switch", "template", "this", "true", "typedef", "uimage1D", "uimage1DArray", "uimage2D",
		"uimage2DArray", "uimage2DMS", "uimage2DMSArray", "uimage2DRect", "uimage3D", "uimageBuffer", "uimageCube",
		"uimageCubeArray", "uint", "uniform", "union", "unsigned", "usampler1D", "usampler1DArray", "usampler2D", "usampler2DArray",
		"usampler2DMS", "usampler2DMSArray", "usampler2DRect", "usampler3D", "usamplerBuffer", "usamplerCube",
		"usamplerCubeArray", "using", "uvec2", "uvec3", "uvec4", "varying", "vec2", "vec3", "vec4", "void", "volatile",
		"while", "writeonly",
	};
	// clang-format on

	CompilerGLSL_replace_illegal_names(keywords);
}

string CompilerHLSL::CompilerGLSL_to_func_call_arg(const SPIRFunction::Parameter &, uint32_t id)
{
	// Make sure that we use the name of the original variable, and not the parameter alias.
	uint32_t name_id = id;
	auto *var = maybe_get<SPIRVariable>(id);
	if (var && var->basevariable)
		name_id = var->basevariable;
	return to_expression(name_id);
}

void CompilerHLSL::CompilerGLSL_emit_glsl_op(uint32_t result_type, uint32_t id, uint32_t eop, const uint32_t *args, uint32_t length)
{
	auto op = static_cast<GLSLstd450>(eop);

	if (is_legacy() && is_unsigned_glsl_opcode(op))
		SPIRV_CROSS_THROW("Unsigned integers are not supported on legacy GLSL targets.");

	// If we need to do implicit bitcasts, make sure we do it with the correct type.
	uint32_t integer_width = get_integer_width_for_glsl_instruction(op, args, length);
	auto int_type = to_signed_basetype(integer_width);
	auto uint_type = to_unsigned_basetype(integer_width);

	op = get_remapped_glsl_op(op);

	switch (op)
	{
	// FP fiddling
	case GLSLstd450Round:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "round");
		else
		{
			auto op0 = to_enclosed_expression(args[0]);
			auto &op0_type = expression_type(args[0]);
			auto expr = join("floor(", op0, " + ", type_to_glsl_constructor(op0_type), "(0.5))");
			bool forward = should_forward(args[0]);
			emit_op(result_type, id, expr, forward);
			inherit_expression_dependencies(id, args[0]);
		}
		break;

	case GLSLstd450RoundEven:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "roundEven");
		else if (!options.es)
		{
			// This extension provides round() with round-to-even semantics.
			require_extension_internal("GL_EXT_gpu_shader4");
			emit_unary_func_op(result_type, id, args[0], "round");
		}
		else
			SPIRV_CROSS_THROW("roundEven supported only in ESSL 300.");
		break;

	case GLSLstd450Trunc:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "trunc");
		else
		{
			// Implement by value-casting to int and back.
			bool forward = should_forward(args[0]);
			auto op0 = to_unpacked_expression(args[0]);
			auto &op0_type = expression_type(args[0]);
			auto via_type = op0_type;
			via_type.basetype = SPIRType::Int;
			auto expr = join(type_to_glsl(op0_type), "(", type_to_glsl(via_type), "(", op0, "))");
			emit_op(result_type, id, expr, forward);
			inherit_expression_dependencies(id, args[0]);
		}
		break;

	case GLSLstd450SAbs:
		emit_unary_func_op_cast(result_type, id, args[0], "abs", int_type, int_type);
		break;
	case GLSLstd450FAbs:
		emit_unary_func_op(result_type, id, args[0], "abs");
		break;
	case GLSLstd450SSign:
		emit_unary_func_op_cast(result_type, id, args[0], "sign", int_type, int_type);
		break;
	case GLSLstd450FSign:
		emit_unary_func_op(result_type, id, args[0], "sign");
		break;
	case GLSLstd450Floor:
		emit_unary_func_op(result_type, id, args[0], "floor");
		break;
	case GLSLstd450Ceil:
		emit_unary_func_op(result_type, id, args[0], "ceil");
		break;
	case GLSLstd450Fract:
		emit_unary_func_op(result_type, id, args[0], "fract");
		break;
	case GLSLstd450Radians:
		emit_unary_func_op(result_type, id, args[0], "radians");
		break;
	case GLSLstd450Degrees:
		emit_unary_func_op(result_type, id, args[0], "degrees");
		break;
	case GLSLstd450Fma:
		if ((!options.es && options.version < 400) || (options.es && options.version < 320))
		{
			auto expr = join(to_enclosed_expression(args[0]), " * ", to_enclosed_expression(args[1]), " + ",
			                 to_enclosed_expression(args[2]));

			emit_op(result_type, id, expr,
			        should_forward(args[0]) && should_forward(args[1]) && should_forward(args[2]));
			for (uint32_t i = 0; i < 3; i++)
				inherit_expression_dependencies(id, args[i]);
		}
		else
			emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "fma");
		break;

	case GLSLstd450Modf:
		register_call_out_argument(args[1]);
		if (!is_legacy())
		{
			forced_temporaries.insert(id);
			emit_binary_func_op(result_type, id, args[0], args[1], "modf");
		}
		else
		{
			//NB. legacy GLSL doesn't have trunc() either, so we do a value cast
			auto &op1_type = expression_type(args[1]);
			auto via_type = op1_type;
			via_type.basetype = SPIRType::Int;
			statement(to_expression(args[1]), " = ",
			          type_to_glsl(op1_type), "(", type_to_glsl(via_type),
			          "(", to_expression(args[0]), "));");
			emit_binary_op(result_type, id, args[0], args[1], "-");
		}
		break;

	case GLSLstd450ModfStruct:
	{
		auto &type = get<SPIRType>(result_type);
		emit_uninitialized_temporary_expression(result_type, id);
		if (!is_legacy())
		{
			statement(to_expression(id), ".", to_member_name(type, 0), " = ", "modf(", to_expression(args[0]), ", ",
			          to_expression(id), ".", to_member_name(type, 1), ");");
		}
		else
		{
			//NB. legacy GLSL doesn't have trunc() either, so we do a value cast
			auto &op0_type = expression_type(args[0]);
			auto via_type = op0_type;
			via_type.basetype = SPIRType::Int;
			statement(to_expression(id), ".", to_member_name(type, 1), " = ", type_to_glsl(op0_type),
			          "(", type_to_glsl(via_type), "(", to_expression(args[0]), "));");
			statement(to_expression(id), ".", to_member_name(type, 0), " = ", to_enclosed_expression(args[0]), " - ",
			          to_expression(id), ".", to_member_name(type, 1), ";");
		}
		break;
	}

	// Minmax
	case GLSLstd450UMin:
		emit_binary_func_op_cast(result_type, id, args[0], args[1], "min", uint_type, false);
		break;

	case GLSLstd450SMin:
		emit_binary_func_op_cast(result_type, id, args[0], args[1], "min", int_type, false);
		break;

	case GLSLstd450FMin:
		emit_binary_func_op(result_type, id, args[0], args[1], "min");
		break;

	case GLSLstd450FMax:
		emit_binary_func_op(result_type, id, args[0], args[1], "max");
		break;

	case GLSLstd450UMax:
		emit_binary_func_op_cast(result_type, id, args[0], args[1], "max", uint_type, false);
		break;

	case GLSLstd450SMax:
		emit_binary_func_op_cast(result_type, id, args[0], args[1], "max", int_type, false);
		break;

	case GLSLstd450FClamp:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "clamp");
		break;

	case GLSLstd450UClamp:
		emit_trinary_func_op_cast(result_type, id, args[0], args[1], args[2], "clamp", uint_type);
		break;

	case GLSLstd450SClamp:
		emit_trinary_func_op_cast(result_type, id, args[0], args[1], args[2], "clamp", int_type);
		break;

	// Trig
	case GLSLstd450Sin:
		emit_unary_func_op(result_type, id, args[0], "sin");
		break;
	case GLSLstd450Cos:
		emit_unary_func_op(result_type, id, args[0], "cos");
		break;
	case GLSLstd450Tan:
		emit_unary_func_op(result_type, id, args[0], "tan");
		break;
	case GLSLstd450Asin:
		emit_unary_func_op(result_type, id, args[0], "asin");
		break;
	case GLSLstd450Acos:
		emit_unary_func_op(result_type, id, args[0], "acos");
		break;
	case GLSLstd450Atan:
		emit_unary_func_op(result_type, id, args[0], "atan");
		break;
	case GLSLstd450Sinh:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "sinh");
		else
		{
			bool forward = should_forward(args[0]);
			auto expr = join("(exp(", to_expression(args[0]), ") - exp(-", to_enclosed_expression(args[0]), ")) * 0.5");
			emit_op(result_type, id, expr, forward);
			inherit_expression_dependencies(id, args[0]);
		}
		break;
	case GLSLstd450Cosh:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "cosh");
		else
		{
			bool forward = should_forward(args[0]);
			auto expr = join("(exp(", to_expression(args[0]), ") + exp(-", to_enclosed_expression(args[0]), ")) * 0.5");
			emit_op(result_type, id, expr, forward);
			inherit_expression_dependencies(id, args[0]);
		}
		break;
	case GLSLstd450Tanh:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "tanh");
		else
		{
			// Create temporaries to store the result of exp(arg) and exp(-arg).
			uint32_t &ids = extra_sub_expressions[id];
			if (!ids)
			{
				ids = ir.increase_bound_by(2);

				// Inherit precision qualifier (legacy has no NoContraction).
				if (has_decoration(id, DecorationRelaxedPrecision))
				{
					set_decoration(ids, DecorationRelaxedPrecision);
					set_decoration(ids + 1, DecorationRelaxedPrecision);
				}
			}
			uint32_t epos_id = ids;
			uint32_t eneg_id = ids + 1;

			emit_op(result_type, epos_id, join("exp(", to_expression(args[0]), ")"), false);
			emit_op(result_type, eneg_id, join("exp(-", to_enclosed_expression(args[0]), ")"), false);
			inherit_expression_dependencies(epos_id, args[0]);
			inherit_expression_dependencies(eneg_id, args[0]);

			auto expr = join("(", to_enclosed_expression(epos_id), " - ", to_enclosed_expression(eneg_id), ") / "
			                 "(", to_enclosed_expression(epos_id), " + ", to_enclosed_expression(eneg_id), ")");
			emit_op(result_type, id, expr, true);
			inherit_expression_dependencies(id, epos_id);
			inherit_expression_dependencies(id, eneg_id);
		}
		break;
	case GLSLstd450Asinh:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "asinh");
		else
			emit_emulated_ahyper_op(result_type, id, args[0], GLSLstd450Asinh);
		break;
	case GLSLstd450Acosh:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "acosh");
		else
			emit_emulated_ahyper_op(result_type, id, args[0], GLSLstd450Acosh);
		break;
	case GLSLstd450Atanh:
		if (!is_legacy())
			emit_unary_func_op(result_type, id, args[0], "atanh");
		else
			emit_emulated_ahyper_op(result_type, id, args[0], GLSLstd450Atanh);
		break;
	case GLSLstd450Atan2:
		emit_binary_func_op(result_type, id, args[0], args[1], "atan");
		break;

	// Exponentials
	case GLSLstd450Pow:
		emit_binary_func_op(result_type, id, args[0], args[1], "pow");
		break;
	case GLSLstd450Exp:
		emit_unary_func_op(result_type, id, args[0], "exp");
		break;
	case GLSLstd450Log:
		emit_unary_func_op(result_type, id, args[0], "log");
		break;
	case GLSLstd450Exp2:
		emit_unary_func_op(result_type, id, args[0], "exp2");
		break;
	case GLSLstd450Log2:
		emit_unary_func_op(result_type, id, args[0], "log2");
		break;
	case GLSLstd450Sqrt:
		emit_unary_func_op(result_type, id, args[0], "sqrt");
		break;
	case GLSLstd450InverseSqrt:
		emit_unary_func_op(result_type, id, args[0], "inversesqrt");
		break;

	// Matrix math
	case GLSLstd450Determinant:
	{
		// No need to transpose - it doesn't affect the determinant
		auto *e = maybe_get<SPIRExpression>(args[0]);
		bool old_transpose = e && e->need_transpose;
		if (old_transpose)
			e->need_transpose = false;

		if (options.version < 150) // also matches ES 100
		{
			auto &type = expression_type(args[0]);
			assert(type.vecsize >= 2 && type.vecsize <= 4);
			assert(type.vecsize == type.columns);

			// ARB_gpu_shader_fp64 needs GLSL 150, other types are not valid
			if (type.basetype != SPIRType::Float)
				SPIRV_CROSS_THROW("Unsupported type for matrix determinant");

			bool relaxed = has_decoration(id, DecorationRelaxedPrecision);
			require_polyfill(static_cast<Polyfill>(PolyfillDeterminant2x2 << (type.vecsize - 2)),
			                 relaxed);
			emit_unary_func_op(result_type, id, args[0],
			                   (options.es && relaxed) ? "spvDeterminantMP" : "spvDeterminant");
		}
		else
			emit_unary_func_op(result_type, id, args[0], "determinant");

		if (old_transpose)
			e->need_transpose = true;
		break;
	}

	case GLSLstd450MatrixInverse:
	{
		// The inverse of the transpose is the same as the transpose of
		// the inverse, so we can just flip need_transpose of the result.
		auto *a = maybe_get<SPIRExpression>(args[0]);
		bool old_transpose = a && a->need_transpose;
		if (old_transpose)
			a->need_transpose = false;

		const char *func = "inverse";
		if (options.version < 140) // also matches ES 100
		{
			auto &type = get<SPIRType>(result_type);
			assert(type.vecsize >= 2 && type.vecsize <= 4);
			assert(type.vecsize == type.columns);

			// ARB_gpu_shader_fp64 needs GLSL 150, other types are invalid
			if (type.basetype != SPIRType::Float)
				SPIRV_CROSS_THROW("Unsupported type for matrix inverse");

			bool relaxed = has_decoration(id, DecorationRelaxedPrecision);
			require_polyfill(static_cast<Polyfill>(PolyfillMatrixInverse2x2 << (type.vecsize - 2)),
			                 relaxed);
			func = (options.es && relaxed) ? "spvInverseMP" : "spvInverse";
		}

		bool forward = should_forward(args[0]);
		auto &e = emit_op(result_type, id, join(func, "(", to_unpacked_expression(args[0]), ")"), forward);
		inherit_expression_dependencies(id, args[0]);

		if (old_transpose)
		{
			e.need_transpose = true;
			a->need_transpose = true;
		}
		break;
	}

	// Lerping
	case GLSLstd450FMix:
	case GLSLstd450IMix:
	{
		emit_mix_op(result_type, id, args[0], args[1], args[2]);
		break;
	}
	case GLSLstd450Step:
		emit_binary_func_op(result_type, id, args[0], args[1], "step");
		break;
	case GLSLstd450SmoothStep:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "smoothstep");
		break;

	// Packing
	case GLSLstd450Frexp:
		register_call_out_argument(args[1]);
		forced_temporaries.insert(id);
		emit_binary_func_op(result_type, id, args[0], args[1], "frexp");
		break;

	case GLSLstd450FrexpStruct:
	{
		auto &type = get<SPIRType>(result_type);
		emit_uninitialized_temporary_expression(result_type, id);
		statement(to_expression(id), ".", to_member_name(type, 0), " = ", "frexp(", to_expression(args[0]), ", ",
		          to_expression(id), ".", to_member_name(type, 1), ");");
		break;
	}

	case GLSLstd450Ldexp:
	{
		bool forward = should_forward(args[0]) && should_forward(args[1]);

		auto op0 = to_unpacked_expression(args[0]);
		auto op1 = to_unpacked_expression(args[1]);
		auto &op1_type = expression_type(args[1]);
		if (op1_type.basetype != SPIRType::Int)
		{
			// Need a value cast here.
			auto target_type = op1_type;
			target_type.basetype = SPIRType::Int;
			op1 = join(type_to_glsl_constructor(target_type), "(", op1, ")");
		}

		auto expr = join("ldexp(", op0, ", ", op1, ")");

		emit_op(result_type, id, expr, forward);
		inherit_expression_dependencies(id, args[0]);
		inherit_expression_dependencies(id, args[1]);
		break;
	}

	case GLSLstd450PackSnorm4x8:
		emit_unary_func_op(result_type, id, args[0], "packSnorm4x8");
		break;
	case GLSLstd450PackUnorm4x8:
		emit_unary_func_op(result_type, id, args[0], "packUnorm4x8");
		break;
	case GLSLstd450PackSnorm2x16:
		emit_unary_func_op(result_type, id, args[0], "packSnorm2x16");
		break;
	case GLSLstd450PackUnorm2x16:
		emit_unary_func_op(result_type, id, args[0], "packUnorm2x16");
		break;
	case GLSLstd450PackHalf2x16:
		emit_unary_func_op(result_type, id, args[0], "packHalf2x16");
		break;
	case GLSLstd450UnpackSnorm4x8:
		emit_unary_func_op(result_type, id, args[0], "unpackSnorm4x8");
		break;
	case GLSLstd450UnpackUnorm4x8:
		emit_unary_func_op(result_type, id, args[0], "unpackUnorm4x8");
		break;
	case GLSLstd450UnpackSnorm2x16:
		emit_unary_func_op(result_type, id, args[0], "unpackSnorm2x16");
		break;
	case GLSLstd450UnpackUnorm2x16:
		emit_unary_func_op(result_type, id, args[0], "unpackUnorm2x16");
		break;
	case GLSLstd450UnpackHalf2x16:
		emit_unary_func_op(result_type, id, args[0], "unpackHalf2x16");
		break;

	case GLSLstd450PackDouble2x32:
		emit_unary_func_op(result_type, id, args[0], "packDouble2x32");
		break;
	case GLSLstd450UnpackDouble2x32:
		emit_unary_func_op(result_type, id, args[0], "unpackDouble2x32");
		break;

	// Vector math
	case GLSLstd450Length:
		emit_unary_func_op(result_type, id, args[0], "length");
		break;
	case GLSLstd450Distance:
		emit_binary_func_op(result_type, id, args[0], args[1], "distance");
		break;
	case GLSLstd450Cross:
		emit_binary_func_op(result_type, id, args[0], args[1], "cross");
		break;
	case GLSLstd450Normalize:
		emit_unary_func_op(result_type, id, args[0], "normalize");
		break;
	case GLSLstd450FaceForward:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "faceforward");
		break;
	case GLSLstd450Reflect:
		emit_binary_func_op(result_type, id, args[0], args[1], "reflect");
		break;
	case GLSLstd450Refract:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "refract");
		break;

	// Bit-fiddling
	case GLSLstd450FindILsb:
		// findLSB always returns int.
		emit_unary_func_op_cast(result_type, id, args[0], "findLSB", expression_type(args[0]).basetype, int_type);
		break;

	case GLSLstd450FindSMsb:
		emit_unary_func_op_cast(result_type, id, args[0], "findMSB", int_type, int_type);
		break;

	case GLSLstd450FindUMsb:
		emit_unary_func_op_cast(result_type, id, args[0], "findMSB", uint_type,
		                        int_type); // findMSB always returns int.
		break;

	// Multisampled varying
	case GLSLstd450InterpolateAtCentroid:
		emit_unary_func_op(result_type, id, args[0], "interpolateAtCentroid");
		break;
	case GLSLstd450InterpolateAtSample:
		emit_binary_func_op(result_type, id, args[0], args[1], "interpolateAtSample");
		break;
	case GLSLstd450InterpolateAtOffset:
		emit_binary_func_op(result_type, id, args[0], args[1], "interpolateAtOffset");
		break;

	case GLSLstd450NMin:
	case GLSLstd450NMax:
	{
		emit_nminmax_op(result_type, id, args[0], args[1], op);
		break;
	}

	case GLSLstd450NClamp:
	{
		// Make sure we have a unique ID here to avoid aliasing the extra sub-expressions between clamp and NMin sub-op.
		// IDs cannot exceed 24 bits, so we can make use of the higher bits for some unique flags.
		uint32_t &max_id = extra_sub_expressions[id | EXTRA_SUB_EXPRESSION_TYPE_AUX];
		if (!max_id)
			max_id = ir.increase_bound_by(1);

		// Inherit precision qualifiers.
		ir.meta[max_id] = ir.meta[id];

		emit_nminmax_op(result_type, max_id, args[0], args[1], GLSLstd450NMax);
		emit_nminmax_op(result_type, id, max_id, args[2], GLSLstd450NMin);
		break;
	}

	default:
		statement("// unimplemented GLSL op ", eop);
		break;
	}
}

void CompilerHLSL::CompilerGLSL_emit_instruction(const Instruction &instruction)
{
	auto ops = stream(instruction);
	auto opcode = static_cast<Op>(instruction.op);
	uint32_t length = instruction.length;

#define GLSL_BOP(op) emit_binary_op(ops[0], ops[1], ops[2], ops[3], #op)
#define GLSL_BOP_CAST(op, type) \
	emit_binary_op_cast(ops[0], ops[1], ops[2], ops[3], #op, type, \
	                    opcode_is_sign_invariant(opcode), implicit_integer_promotion)
#define GLSL_UOP(op) emit_unary_op(ops[0], ops[1], ops[2], #op)
#define GLSL_UOP_CAST(op) emit_unary_op_cast(ops[0], ops[1], ops[2], #op)
#define GLSL_QFOP(op) emit_quaternary_func_op(ops[0], ops[1], ops[2], ops[3], ops[4], ops[5], #op)
#define GLSL_TFOP(op) emit_trinary_func_op(ops[0], ops[1], ops[2], ops[3], ops[4], #op)
#define GLSL_BFOP(op) emit_binary_func_op(ops[0], ops[1], ops[2], ops[3], #op)
#define GLSL_BFOP_CAST(op, type) \
	emit_binary_func_op_cast(ops[0], ops[1], ops[2], ops[3], #op, type, opcode_is_sign_invariant(opcode))
#define GLSL_BFOP(op) emit_binary_func_op(ops[0], ops[1], ops[2], ops[3], #op)
#define GLSL_UFOP(op) emit_unary_func_op(ops[0], ops[1], ops[2], #op)

	// If we need to do implicit bitcasts, make sure we do it with the correct type.
	uint32_t integer_width = get_integer_width_for_instruction(instruction);
	auto int_type = to_signed_basetype(integer_width);
	auto uint_type = to_unsigned_basetype(integer_width);

	// Handle C implicit integer promotion rules.
	// If we get implicit promotion to int, need to make sure we cast by value to intended return type,
	// otherwise, future sign-dependent operations and bitcasts will break.
	bool implicit_integer_promotion = integer_width < 32 && backend.implicit_c_integer_promotion_rules &&
	                                  opcode_can_promote_integer_implicitly(opcode) &&
	                                  get<SPIRType>(ops[0]).vecsize == 1;

	opcode = get_remapped_spirv_op(opcode);

	switch (opcode)
	{
	// Dealing with memory
	case OpLoad:
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t ptr = ops[2];

		flush_variable_declaration(ptr);

		// If we're loading from memory that cannot be changed by the shader,
		// just forward the expression directly to avoid needless temporaries.
		// If an expression is mutable and forwardable, we speculate that it is immutable.
		bool forward = should_forward(ptr) && forced_temporaries.find(id) == end(forced_temporaries);

		// If loading a non-native row-major matrix, mark the expression as need_transpose.
		bool need_transpose = false;
		bool old_need_transpose = false;

		auto *ptr_expression = maybe_get<SPIRExpression>(ptr);

		if (forward)
		{
			// If we're forwarding the load, we're also going to forward transpose state, so don't transpose while
			// taking the expression.
			if (ptr_expression && ptr_expression->need_transpose)
			{
				old_need_transpose = true;
				ptr_expression->need_transpose = false;
				need_transpose = true;
			}
			else if (is_non_native_row_major_matrix(ptr))
				need_transpose = true;
		}

		// If we are forwarding this load,
		// don't register the read to access chain here, defer that to when we actually use the expression,
		// using the add_implied_read_expression mechanism.
		string expr;

		bool is_packed = has_extended_decoration(ptr, SPIRVCrossDecorationPhysicalTypePacked);
		bool is_remapped = has_extended_decoration(ptr, SPIRVCrossDecorationPhysicalTypeID);
		if (forward || (!is_packed && !is_remapped))
		{
			// For the simple case, we do not need to deal with repacking.
			expr = to_dereferenced_expression(ptr, false);
		}
		else
		{
			// If we are not forwarding the expression, we need to unpack and resolve any physical type remapping here before
			// storing the expression to a temporary.
			expr = to_unpacked_expression(ptr);
		}

		auto &type = get<SPIRType>(result_type);
		auto &expr_type = expression_type(ptr);

		// If the expression has more vector components than the result type, insert
		// a swizzle. This shouldn't happen normally on valid SPIR-V, but it might
		// happen with e.g. the MSL backend replacing the type of an input variable.
		if (expr_type.vecsize > type.vecsize)
			expr = enclose_expression(expr + vector_swizzle(type.vecsize, 0));

		if (forward && ptr_expression)
			ptr_expression->need_transpose = old_need_transpose;

		// We might need to cast in order to load from a builtin.
		cast_from_variable_load(ptr, expr, type);

		if (forward && ptr_expression)
			ptr_expression->need_transpose = false;

		// We might be trying to load a gl_Position[N], where we should be
		// doing float4[](gl_in[i].gl_Position, ...) instead.
		// Similar workarounds are required for input arrays in tessellation.
		// Also, loading from gl_SampleMask array needs special unroll.
		unroll_array_from_complex_load(id, ptr, expr);

		if (!type_is_opaque_value(type) && has_decoration(ptr, DecorationNonUniform))
		{
			// If we're loading something non-opaque, we need to handle non-uniform descriptor access.
			convert_non_uniform_expression(expr, ptr);
		}

		if (forward && ptr_expression)
			ptr_expression->need_transpose = old_need_transpose;

		bool flattened = ptr_expression && flattened_buffer_blocks.count(ptr_expression->loaded_from) != 0;

		if (backend.needs_row_major_load_workaround && !is_non_native_row_major_matrix(ptr) && !flattened)
			rewrite_load_for_wrapped_row_major(expr, result_type, ptr);

		// By default, suppress usage tracking since using same expression multiple times does not imply any extra work.
		// However, if we try to load a complex, composite object from a flattened buffer,
		// we should avoid emitting the same code over and over and lower the result to a temporary.
		bool usage_tracking = flattened && (type.basetype == SPIRType::Struct || (type.columns > 1));

		SPIRExpression *e = nullptr;
		if (!forward && expression_is_non_value_type_array(ptr))
		{
			// Complicated load case where we need to make a copy of ptr, but we cannot, because
			// it is an array, and our backend does not support arrays as value types.
			// Emit the temporary, and copy it explicitly.
			e = &emit_uninitialized_temporary_expression(result_type, id);
			emit_array_copy(nullptr, id, ptr, StorageClassFunction, get_expression_effective_storage_class(ptr));
		}
		else
			e = &emit_op(result_type, id, expr, forward, !usage_tracking);

		e->need_transpose = need_transpose;
		register_read(id, ptr, forward);

		if (forward)
		{
			// Pass through whether the result is of a packed type and the physical type ID.
			if (has_extended_decoration(ptr, SPIRVCrossDecorationPhysicalTypePacked))
				set_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked);
			if (has_extended_decoration(ptr, SPIRVCrossDecorationPhysicalTypeID))
			{
				set_extended_decoration(id, SPIRVCrossDecorationPhysicalTypeID,
				                        get_extended_decoration(ptr, SPIRVCrossDecorationPhysicalTypeID));
			}
		}
		else
		{
			// This might have been set on an earlier compilation iteration, force it to be unset.
			unset_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked);
			unset_extended_decoration(id, SPIRVCrossDecorationPhysicalTypeID);
		}

		inherit_expression_dependencies(id, ptr);
		if (forward)
			add_implied_read_expression(*e, ptr);
		break;
	}

	case OpInBoundsAccessChain:
	case OpAccessChain:
	case OpPtrAccessChain:
	{
		auto *var = maybe_get<SPIRVariable>(ops[2]);
		if (var)
			flush_variable_declaration(var->self);

		// If the base is immutable, the access chain pointer must also be.
		// If an expression is mutable and forwardable, we speculate that it is immutable.
		AccessChainMeta meta;
		bool ptr_chain = opcode == OpPtrAccessChain;
		auto &target_type = get<SPIRType>(ops[0]);
		auto e = access_chain(ops[2], &ops[3], length - 3, target_type, &meta, ptr_chain);

		// If the base is flattened UBO of struct type, the expression has to be a composite.
		// In that case, backends which do not support inline syntax need it to be bound to a temporary.
		// Otherwise, invalid expressions like ({UBO[0].xyz, UBO[0].w, UBO[1]}).member are emitted.
		bool requires_temporary = false;
		if (flattened_buffer_blocks.count(ops[2]) && target_type.basetype == SPIRType::Struct)
			requires_temporary = !backend.can_declare_struct_inline;

		auto &expr = requires_temporary ?
                         emit_op(ops[0], ops[1], std::move(e), false) :
                         set<SPIRExpression>(ops[1], std::move(e), ops[0], should_forward(ops[2]));

		auto *backing_variable = maybe_get_backing_variable(ops[2]);
		expr.loaded_from = backing_variable ? backing_variable->self : ID(ops[2]);
		expr.need_transpose = meta.need_transpose;
		expr.access_chain = true;
		expr.access_meshlet_position_y = meta.access_meshlet_position_y;

		// Mark the result as being packed. Some platforms handled packed vectors differently than non-packed.
		if (meta.storage_is_packed)
			set_extended_decoration(ops[1], SPIRVCrossDecorationPhysicalTypePacked);
		if (meta.storage_physical_type != 0)
			set_extended_decoration(ops[1], SPIRVCrossDecorationPhysicalTypeID, meta.storage_physical_type);
		if (meta.storage_is_invariant)
			set_decoration(ops[1], DecorationInvariant);
		if (meta.flattened_struct)
			flattened_structs[ops[1]] = true;
		if (meta.relaxed_precision && backend.requires_relaxed_precision_analysis)
			set_decoration(ops[1], DecorationRelaxedPrecision);

		// If we have some expression dependencies in our access chain, this access chain is technically a forwarded
		// temporary which could be subject to invalidation.
		// Need to assume we're forwarded while calling inherit_expression_depdendencies.
		forwarded_temporaries.insert(ops[1]);
		// The access chain itself is never forced to a temporary, but its dependencies might.
		suppressed_usage_tracking.insert(ops[1]);

		for (uint32_t i = 2; i < length; i++)
		{
			inherit_expression_dependencies(ops[1], ops[i]);
			add_implied_read_expression(expr, ops[i]);
		}

		// If we have no dependencies after all, i.e., all indices in the access chain are immutable temporaries,
		// we're not forwarded after all.
		if (expr.expression_dependencies.empty())
			forwarded_temporaries.erase(ops[1]);

		break;
	}

	case OpStore:
	{
		auto *var = maybe_get<SPIRVariable>(ops[0]);

		if (var && var->statically_assigned)
			var->static_expression = ops[1];
		else if (var && var->loop_variable && !var->loop_variable_enable)
			var->static_expression = ops[1];
		else if (var && var->remapped_variable && var->static_expression)
		{
			// Skip the write.
		}
		else if (flattened_structs.count(ops[0]))
		{
			store_flattened_struct(ops[0], ops[1]);
			register_write(ops[0]);
		}
		else
		{
			emit_store_statement(ops[0], ops[1]);
		}

		// Storing a pointer results in a variable pointer, so we must conservatively assume
		// we can write through it.
		if (expression_type(ops[1]).pointer)
			register_write(ops[1]);
		break;
	}

	case OpArrayLength:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		auto e = access_chain_internal(ops[2], &ops[3], length - 3, ACCESS_CHAIN_INDEX_IS_LITERAL_BIT, nullptr);
		if (has_decoration(ops[2], DecorationNonUniform))
			convert_non_uniform_expression(e, ops[2]);
		set<SPIRExpression>(id, join(type_to_glsl(get<SPIRType>(result_type)), "(", e, ".length())"), result_type,
		                    true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Function calls
	case OpFunctionCall:
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t func = ops[2];
		const auto *arg = &ops[3];
		length -= 3;

		auto &callee = get<SPIRFunction>(func);
		auto &return_type = get<SPIRType>(callee.return_type);
		bool pure = function_is_pure(callee);

		bool callee_has_out_variables = false;
		bool emit_return_value_as_argument = false;

		// Invalidate out variables passed to functions since they can be OpStore'd to.
		for (uint32_t i = 0; i < length; i++)
		{
			if (callee.arguments[i].write_count)
			{
				register_call_out_argument(arg[i]);
				callee_has_out_variables = true;
			}

			flush_variable_declaration(arg[i]);
		}

		if (!return_type.array.empty() && !backend.can_return_array)
		{
			callee_has_out_variables = true;
			emit_return_value_as_argument = true;
		}

		if (!pure)
			register_impure_function_call();

		string funexpr;
		SmallVector<string> arglist;
		funexpr += to_name(func) + "(";

		if (emit_return_value_as_argument)
		{
			statement(type_to_glsl(return_type), " ", to_name(id), type_to_array_glsl(return_type), ";");
			arglist.push_back(to_name(id));
		}

		for (uint32_t i = 0; i < length; i++)
		{
			// Do not pass in separate images or samplers if we're remapping
			// to combined image samplers.
			if (skip_argument(arg[i]))
				continue;

			arglist.push_back(to_func_call_arg(callee.arguments[i], arg[i]));
		}

		for (auto &combined : callee.combined_parameters)
		{
			auto image_id = combined.global_image ? combined.image_id : VariableID(arg[combined.image_id]);
			auto sampler_id = combined.global_sampler ? combined.sampler_id : VariableID(arg[combined.sampler_id]);
			arglist.push_back(to_combined_image_sampler(image_id, sampler_id));
		}

		append_global_func_args(callee, length, arglist);

		funexpr += merge(arglist);
		funexpr += ")";

		// Check for function call constraints.
		check_function_call_constraints(arg, length);

		if (return_type.basetype != SPIRType::Void)
		{
			// If the function actually writes to an out variable,
			// take the conservative route and do not forward.
			// The problem is that we might not read the function
			// result (and emit the function) before an out variable
			// is read (common case when return value is ignored!
			// In order to avoid start tracking invalid variables,
			// just avoid the forwarding problem altogether.
			bool forward = args_will_forward(id, arg, length, pure) && !callee_has_out_variables && pure &&
			               (forced_temporaries.find(id) == end(forced_temporaries));

			if (emit_return_value_as_argument)
			{
				statement(funexpr, ";");
				set<SPIRExpression>(id, to_name(id), result_type, true);
			}
			else
				emit_op(result_type, id, funexpr, forward);

			// Function calls are implicit loads from all variables in question.
			// Set dependencies for them.
			for (uint32_t i = 0; i < length; i++)
				register_read(id, arg[i], forward);

			// If we're going to forward the temporary result,
			// put dependencies on every variable that must not change.
			if (forward)
				register_global_read_dependencies(callee, id);
		}
		else
			statement(funexpr, ";");

		break;
	}

	// Composite munging
	case OpCompositeConstruct:
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		const auto *const elems = &ops[2];
		length -= 2;

		bool forward = true;
		for (uint32_t i = 0; i < length; i++)
			forward = forward && should_forward(elems[i]);

		auto &out_type = get<SPIRType>(result_type);
		auto *in_type = length > 0 ? &expression_type(elems[0]) : nullptr;

		// Only splat if we have vector constructors.
		// Arrays and structs must be initialized properly in full.
		bool composite = !out_type.array.empty() || out_type.basetype == SPIRType::Struct;

		bool splat = false;
		bool swizzle_splat = false;

		if (in_type)
		{
			splat = in_type->vecsize == 1 && in_type->columns == 1 && !composite && backend.use_constructor_splatting;
			swizzle_splat = in_type->vecsize == 1 && in_type->columns == 1 && backend.can_swizzle_scalar;

			if (ir.ids[elems[0]].get_type() == TypeConstant && !type_is_floating_point(*in_type))
			{
				// Cannot swizzle literal integers as a special case.
				swizzle_splat = false;
			}
		}

		if (splat || swizzle_splat)
		{
			uint32_t input = elems[0];
			for (uint32_t i = 0; i < length; i++)
			{
				if (input != elems[i])
				{
					splat = false;
					swizzle_splat = false;
				}
			}
		}

		if (out_type.basetype == SPIRType::Struct && !backend.can_declare_struct_inline)
			forward = false;
		if (!out_type.array.empty() && !backend.can_declare_arrays_inline)
			forward = false;
		if (type_is_empty(out_type) && !backend.supports_empty_struct)
			forward = false;

		string constructor_op;
		if (backend.use_initializer_list && composite)
		{
			bool needs_trailing_tracket = false;
			// Only use this path if we are building composites.
			// This path cannot be used for arithmetic.
			if (backend.use_typed_initializer_list && out_type.basetype == SPIRType::Struct && out_type.array.empty())
				constructor_op += type_to_glsl_constructor(get<SPIRType>(result_type));
			else if (backend.use_typed_initializer_list && backend.array_is_value_type && !out_type.array.empty())
			{
				// MSL path. Array constructor is baked into type here, do not use _constructor variant.
				constructor_op += type_to_glsl_constructor(get<SPIRType>(result_type)) + "(";
				needs_trailing_tracket = true;
			}
			constructor_op += "{ ";

			if (type_is_empty(out_type) && !backend.supports_empty_struct)
				constructor_op += "0";
			else if (splat)
				constructor_op += to_unpacked_expression(elems[0]);
			else
				constructor_op += build_composite_combiner(result_type, elems, length);
			constructor_op += " }";
			if (needs_trailing_tracket)
				constructor_op += ")";
		}
		else if (swizzle_splat && !composite)
		{
			constructor_op = remap_swizzle(get<SPIRType>(result_type), 1, to_unpacked_expression(elems[0]));
		}
		else
		{
			constructor_op = type_to_glsl_constructor(get<SPIRType>(result_type)) + "(";
			if (type_is_empty(out_type) && !backend.supports_empty_struct)
				constructor_op += "0";
			else if (splat)
				constructor_op += to_unpacked_expression(elems[0]);
			else
				constructor_op += build_composite_combiner(result_type, elems, length);
			constructor_op += ")";
		}

		if (!constructor_op.empty())
		{
			emit_op(result_type, id, constructor_op, forward);
			for (uint32_t i = 0; i < length; i++)
				inherit_expression_dependencies(id, elems[i]);
		}
		break;
	}

	case OpVectorInsertDynamic:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t vec = ops[2];
		uint32_t comp = ops[3];
		uint32_t index = ops[4];

		flush_variable_declaration(vec);

		// Make a copy, then use access chain to store the variable.
		statement(declare_temporary(result_type, id), to_expression(vec), ";");
		set<SPIRExpression>(id, to_name(id), result_type, true);
		auto chain = access_chain_internal(id, &index, 1, 0, nullptr);
		statement(chain, " = ", to_unpacked_expression(comp), ";");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpVectorExtractDynamic:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		auto expr = access_chain_internal(ops[2], &ops[3], 1, 0, nullptr);
		emit_op(result_type, id, expr, should_forward(ops[2]));
		inherit_expression_dependencies(id, ops[2]);
		inherit_expression_dependencies(id, ops[3]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpCompositeExtract:
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		length -= 3;

		auto &type = get<SPIRType>(result_type);

		// We can only split the expression here if our expression is forwarded as a temporary.
		bool allow_base_expression = forced_temporaries.find(id) == end(forced_temporaries);

		// Do not allow base expression for struct members. We risk doing "swizzle" optimizations in this case.
		auto &composite_type = expression_type(ops[2]);
		bool composite_type_is_complex = composite_type.basetype == SPIRType::Struct || !composite_type.array.empty();
		if (composite_type_is_complex)
			allow_base_expression = false;

		// Packed expressions or physical ID mapped expressions cannot be split up.
		if (has_extended_decoration(ops[2], SPIRVCrossDecorationPhysicalTypePacked) ||
		    has_extended_decoration(ops[2], SPIRVCrossDecorationPhysicalTypeID))
			allow_base_expression = false;

		// Cannot use base expression for row-major matrix row-extraction since we need to interleave access pattern
		// into the base expression.
		if (is_non_native_row_major_matrix(ops[2]))
			allow_base_expression = false;

		AccessChainMeta meta;
		SPIRExpression *e = nullptr;
		auto *c = maybe_get<SPIRConstant>(ops[2]);

		if (c && !c->specialization && !composite_type_is_complex)
		{
			auto expr = to_extract_constant_composite_expression(result_type, *c, ops + 3, length);
			e = &emit_op(result_type, id, expr, true, true);
		}
		else if (allow_base_expression && should_forward(ops[2]) && type.vecsize == 1 && type.columns == 1 && length == 1)
		{
			// Only apply this optimization if result is scalar.

			// We want to split the access chain from the base.
			// This is so we can later combine different CompositeExtract results
			// with CompositeConstruct without emitting code like
			//
			// vec3 temp = texture(...).xyz
			// vec4(temp.x, temp.y, temp.z, 1.0).
			//
			// when we actually wanted to emit this
			// vec4(texture(...).xyz, 1.0).
			//
			// Including the base will prevent this and would trigger multiple reads
			// from expression causing it to be forced to an actual temporary in GLSL.
			auto expr = access_chain_internal(ops[2], &ops[3], length,
			                                  ACCESS_CHAIN_INDEX_IS_LITERAL_BIT | ACCESS_CHAIN_CHAIN_ONLY_BIT |
			                                  ACCESS_CHAIN_FORCE_COMPOSITE_BIT, &meta);
			e = &emit_op(result_type, id, expr, true, should_suppress_usage_tracking(ops[2]));
			inherit_expression_dependencies(id, ops[2]);
			e->base_expression = ops[2];

			if (meta.relaxed_precision && backend.requires_relaxed_precision_analysis)
				set_decoration(ops[1], DecorationRelaxedPrecision);
		}
		else
		{
			auto expr = access_chain_internal(ops[2], &ops[3], length,
			                                  ACCESS_CHAIN_INDEX_IS_LITERAL_BIT | ACCESS_CHAIN_FORCE_COMPOSITE_BIT, &meta);
			e = &emit_op(result_type, id, expr, should_forward(ops[2]), should_suppress_usage_tracking(ops[2]));
			inherit_expression_dependencies(id, ops[2]);
		}

		// Pass through some meta information to the loaded expression.
		// We can still end up loading a buffer type to a variable, then CompositeExtract from it
		// instead of loading everything through an access chain.
		e->need_transpose = meta.need_transpose;
		if (meta.storage_is_packed)
			set_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked);
		if (meta.storage_physical_type != 0)
			set_extended_decoration(id, SPIRVCrossDecorationPhysicalTypeID, meta.storage_physical_type);
		if (meta.storage_is_invariant)
			set_decoration(id, DecorationInvariant);

		break;
	}

	case OpCompositeInsert:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t obj = ops[2];
		uint32_t composite = ops[3];
		const auto *elems = &ops[4];
		length -= 4;

		flush_variable_declaration(composite);

		// CompositeInsert requires a copy + modification, but this is very awkward code in HLL.
		// Speculate that the input composite is no longer used, and we can modify it in-place.
		// There are various scenarios where this is not possible to satisfy.
		bool can_modify_in_place = true;
		forced_temporaries.insert(id);

		// Cannot safely RMW PHI variables since they have no way to be invalidated,
		// forcing temporaries is not going to help.
		// This is similar for Constant and Undef inputs.
		// The only safe thing to RMW is SPIRExpression.
		// If the expression has already been used (i.e. used in a continue block), we have to keep using
		// that loop variable, since we won't be able to override the expression after the fact.
		// If the composite is hoisted, we might never be able to properly invalidate any usage
		// of that composite in a subsequent loop iteration.
		if (invalid_expressions.count(composite) ||
		    block_composite_insert_overwrite.count(composite) ||
		    hoisted_temporaries.count(id) || hoisted_temporaries.count(composite) ||
		    maybe_get<SPIRExpression>(composite) == nullptr)
		{
			can_modify_in_place = false;
		}
		else if (backend.requires_relaxed_precision_analysis &&
		         has_decoration(composite, DecorationRelaxedPrecision) !=
		         has_decoration(id, DecorationRelaxedPrecision) &&
		         get<SPIRType>(result_type).basetype != SPIRType::Struct)
		{
			// Similarly, if precision does not match for input and output,
			// we cannot alias them. If we write a composite into a relaxed precision
			// ID, we might get a false truncation.
			can_modify_in_place = false;
		}

		if (can_modify_in_place)
		{
			// Have to make sure the modified SSA value is bound to a temporary so we can modify it in-place.
			if (!forced_temporaries.count(composite))
				force_temporary_and_recompile(composite);

			auto chain = access_chain_internal(composite, elems, length, ACCESS_CHAIN_INDEX_IS_LITERAL_BIT, nullptr);
			statement(chain, " = ", to_unpacked_expression(obj), ";");
			set<SPIRExpression>(id, to_expression(composite), result_type, true);
			invalid_expressions.insert(composite);
			composite_insert_overwritten.insert(composite);
		}
		else
		{
			if (maybe_get<SPIRUndef>(composite) != nullptr)
			{
				emit_uninitialized_temporary_expression(result_type, id);
			}
			else
			{
				// Make a copy, then use access chain to store the variable.
				statement(declare_temporary(result_type, id), to_expression(composite), ";");
				set<SPIRExpression>(id, to_name(id), result_type, true);
			}

			auto chain = access_chain_internal(id, elems, length, ACCESS_CHAIN_INDEX_IS_LITERAL_BIT, nullptr);
			statement(chain, " = ", to_unpacked_expression(obj), ";");
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpCopyMemory:
	{
		uint32_t lhs = ops[0];
		uint32_t rhs = ops[1];
		if (lhs != rhs)
		{
			uint32_t &tmp_id = extra_sub_expressions[instruction.offset | EXTRA_SUB_EXPRESSION_TYPE_STREAM_OFFSET];
			if (!tmp_id)
				tmp_id = ir.increase_bound_by(1);
			uint32_t tmp_type_id = expression_type(rhs).parent_type;

			EmbeddedInstruction fake_load, fake_store;
			fake_load.op = OpLoad;
			fake_load.length = 3;
			fake_load.ops.push_back(tmp_type_id);
			fake_load.ops.push_back(tmp_id);
			fake_load.ops.push_back(rhs);

			fake_store.op = OpStore;
			fake_store.length = 2;
			fake_store.ops.push_back(lhs);
			fake_store.ops.push_back(tmp_id);

			// Load and Store do a *lot* of workarounds, and we'd like to reuse them as much as possible.
			// Synthesize a fake Load and Store pair for CopyMemory.
			emit_instruction(fake_load);
			emit_instruction(fake_store);
		}
		break;
	}

	case OpCopyLogical:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// This is used for copying object of different types, arrays and structs.
		// We need to unroll the copy, element-by-element.
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t rhs = ops[2];

		emit_uninitialized_temporary_expression(result_type, id);
		emit_copy_logical_type(id, result_type, rhs, expression_type_id(rhs), {});
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpCopyObject:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t rhs = ops[2];
		bool pointer = get<SPIRType>(result_type).pointer;

		auto *chain = maybe_get<SPIRAccessChain>(rhs);
		auto *imgsamp = maybe_get<SPIRCombinedImageSampler>(rhs);
		if (chain)
		{
			// Cannot lower to a SPIRExpression, just copy the object.
			auto &e = set<SPIRAccessChain>(id, *chain);
			e.self = id;
		}
		else if (imgsamp)
		{
			// Cannot lower to a SPIRExpression, just copy the object.
			// GLSL does not currently use this type and will never get here, but MSL does.
			// Handled here instead of CompilerMSL for better integration and general handling,
			// and in case GLSL or other subclasses require it in the future.
			auto &e = set<SPIRCombinedImageSampler>(id, *imgsamp);
			e.self = id;
		}
		else if (expression_is_lvalue(rhs) && !pointer)
		{
			// Need a copy.
			// For pointer types, we copy the pointer itself.
			emit_op(result_type, id, to_unpacked_expression(rhs), false);
		}
		else
		{
			// RHS expression is immutable, so just forward it.
			// Copying these things really make no sense, but
			// seems to be allowed anyways.
			auto &e = emit_op(result_type, id, to_expression(rhs), true, true);
			if (pointer)
			{
				auto *var = maybe_get_backing_variable(rhs);
				e.loaded_from = var ? var->self : ID(0);
			}

			// If we're copying an access chain, need to inherit the read expressions.
			auto *rhs_expr = maybe_get<SPIRExpression>(rhs);
			if (rhs_expr)
			{
				e.implied_read_expressions = rhs_expr->implied_read_expressions;
				e.expression_dependencies = rhs_expr->expression_dependencies;
			}
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpVectorShuffle:
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t vec0 = ops[2];
		uint32_t vec1 = ops[3];
		const auto *elems = &ops[4];
		length -= 4;

		auto &type0 = expression_type(vec0);

		// If we have the undefined swizzle index -1, we need to swizzle in undefined data,
		// or in our case, T(0).
		bool shuffle = false;
		for (uint32_t i = 0; i < length; i++)
			if (elems[i] >= type0.vecsize || elems[i] == 0xffffffffu)
				shuffle = true;

		// Cannot use swizzles with packed expressions, force shuffle path.
		if (!shuffle && has_extended_decoration(vec0, SPIRVCrossDecorationPhysicalTypePacked))
			shuffle = true;

		string expr;
		bool should_fwd, trivial_forward;

		if (shuffle)
		{
			should_fwd = should_forward(vec0) && should_forward(vec1);
			trivial_forward = should_suppress_usage_tracking(vec0) && should_suppress_usage_tracking(vec1);

			// Constructor style and shuffling from two different vectors.
			SmallVector<string> args;
			for (uint32_t i = 0; i < length; i++)
			{
				if (elems[i] == 0xffffffffu)
				{
					// Use a constant 0 here.
					// We could use the first component or similar, but then we risk propagating
					// a value we might not need, and bog down codegen.
					SPIRConstant c;
					c.constant_type = type0.parent_type;
					assert(type0.parent_type != ID(0));
					args.push_back(constant_expression(c));
				}
				else if (elems[i] >= type0.vecsize)
					args.push_back(to_extract_component_expression(vec1, elems[i] - type0.vecsize));
				else
					args.push_back(to_extract_component_expression(vec0, elems[i]));
			}
			expr += join(type_to_glsl_constructor(get<SPIRType>(result_type)), "(", merge(args), ")");
		}
		else
		{
			should_fwd = should_forward(vec0);
			trivial_forward = should_suppress_usage_tracking(vec0);

			// We only source from first vector, so can use swizzle.
			// If the vector is packed, unpack it before applying a swizzle (needed for MSL)
			expr += to_enclosed_unpacked_expression(vec0);
			expr += ".";
			for (uint32_t i = 0; i < length; i++)
			{
				assert(elems[i] != 0xffffffffu);
				expr += index_to_swizzle(elems[i]);
			}

			if (backend.swizzle_is_function && length > 1)
				expr += "()";
		}

		// A shuffle is trivial in that it doesn't actually *do* anything.
		// We inherit the forwardedness from our arguments to avoid flushing out to temporaries when it's not really needed.

		emit_op(result_type, id, expr, should_fwd, trivial_forward);

		inherit_expression_dependencies(id, vec0);
		if (vec0 != vec1)
			inherit_expression_dependencies(id, vec1);
		break;
	}

	// ALU
	case OpIsNan:
#ifndef SPIRV_CROSS_WEBMIN
		if (!is_legacy())
			GLSL_UFOP(isnan);
		else
		{
			// Check if the number doesn't equal itself
			auto &type = get<SPIRType>(ops[0]);
			if (type.vecsize > 1)
				emit_binary_func_op(ops[0], ops[1], ops[2], ops[2], "notEqual");
			else
				emit_binary_op(ops[0], ops[1], ops[2], ops[2], "!=");
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpIsInf:
#ifndef SPIRV_CROSS_WEBMIN
		if (!is_legacy())
			GLSL_UFOP(isinf);
		else
		{
			// inf * 2 == inf by IEEE 754 rules, note this also applies to 0.0
			// This is more reliable than checking if product with zero is NaN
			uint32_t result_type = ops[0];
			uint32_t result_id = ops[1];
			uint32_t operand = ops[2];

			auto &type = get<SPIRType>(result_type);
			std::string expr;
			if (type.vecsize > 1)
			{
				expr = type_to_glsl_constructor(type);
				expr += '(';
				for (uint32_t i = 0; i < type.vecsize; i++)
				{
					auto comp = to_extract_component_expression(operand, i);
					expr += join(comp, " != 0.0 && 2.0 * ", comp, " == ", comp);

					if (i + 1 < type.vecsize)
						expr += ", ";
				}
				expr += ')';
			}
			else
			{
				// Register an extra read to force writing out a temporary
				auto oper = to_enclosed_expression(operand);
				track_expression_read(operand);
				expr += join(oper, " != 0.0 && 2.0 * ", oper, " == ", oper);
			}
			emit_op(result_type, result_id, expr, should_forward(operand));

			inherit_expression_dependencies(result_id, operand);
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpSNegate:
#ifndef SPIRV_CROSS_WEBMIN
		if (implicit_integer_promotion || expression_type_id(ops[2]) != ops[0])
			GLSL_UOP_CAST(-);
		else
			GLSL_UOP(-);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpFNegate:
		GLSL_UOP(-);
		break;

	case OpIAdd:
	{
		// For simple arith ops, prefer the output type if there's a mismatch to avoid extra bitcasts.
		auto type = get<SPIRType>(ops[0]).basetype;
		GLSL_BOP_CAST(+, type);
		break;
	}

	case OpFAdd:
		GLSL_BOP(+);
		break;

	case OpISub:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto type = get<SPIRType>(ops[0]).basetype;
		GLSL_BOP_CAST(-, type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFSub:
		GLSL_BOP(-);
		break;

	case OpIMul:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto type = get<SPIRType>(ops[0]).basetype;
		GLSL_BOP_CAST(*, type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpVectorTimesMatrix:
	case OpMatrixTimesVector:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// If the matrix needs transpose, just flip the multiply order.
		auto *e = maybe_get<SPIRExpression>(ops[opcode == OpMatrixTimesVector ? 2 : 3]);
		if (e && e->need_transpose)
		{
			e->need_transpose = false;
			string expr;

			if (opcode == OpMatrixTimesVector)
				expr = join(to_enclosed_unpacked_expression(ops[3]), " * ",
				            enclose_expression(to_unpacked_row_major_matrix_expression(ops[2])));
			else
				expr = join(enclose_expression(to_unpacked_row_major_matrix_expression(ops[3])), " * ",
				            to_enclosed_unpacked_expression(ops[2]));

			bool forward = should_forward(ops[2]) && should_forward(ops[3]);
			emit_op(ops[0], ops[1], expr, forward);
			e->need_transpose = true;
			inherit_expression_dependencies(ops[1], ops[2]);
			inherit_expression_dependencies(ops[1], ops[3]);
		}
		else
			GLSL_BOP(*);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpMatrixTimesMatrix:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto *a = maybe_get<SPIRExpression>(ops[2]);
		auto *b = maybe_get<SPIRExpression>(ops[3]);

		// If both matrices need transpose, we can multiply in flipped order and tag the expression as transposed.
		// a^T * b^T = (b * a)^T.
		if (a && b && a->need_transpose && b->need_transpose)
		{
			a->need_transpose = false;
			b->need_transpose = false;
			auto expr = join(enclose_expression(to_unpacked_row_major_matrix_expression(ops[3])), " * ",
			                 enclose_expression(to_unpacked_row_major_matrix_expression(ops[2])));
			bool forward = should_forward(ops[2]) && should_forward(ops[3]);
			auto &e = emit_op(ops[0], ops[1], expr, forward);
			e.need_transpose = true;
			a->need_transpose = true;
			b->need_transpose = true;
			inherit_expression_dependencies(ops[1], ops[2]);
			inherit_expression_dependencies(ops[1], ops[3]);
		}
		else
			GLSL_BOP(*);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpMatrixTimesScalar:
	{
		auto *a = maybe_get<SPIRExpression>(ops[2]);

		// If the matrix need transpose, just mark the result as needing so.
		if (a && a->need_transpose)
		{
			a->need_transpose = false;
			auto expr = join(enclose_expression(to_unpacked_row_major_matrix_expression(ops[2])), " * ",
			                 to_enclosed_unpacked_expression(ops[3]));
			bool forward = should_forward(ops[2]) && should_forward(ops[3]);
			auto &e = emit_op(ops[0], ops[1], expr, forward);
			e.need_transpose = true;
			a->need_transpose = true;
			inherit_expression_dependencies(ops[1], ops[2]);
			inherit_expression_dependencies(ops[1], ops[3]);
		}
		else
			GLSL_BOP(*);
		break;
	}

	case OpFMul:
	case OpVectorTimesScalar:
		GLSL_BOP(*);
		break;

	case OpOuterProduct:
#ifndef SPIRV_CROSS_WEBMIN
		if (options.version < 120) // Matches GLSL 1.10 / ESSL 1.00
		{
			uint32_t result_type = ops[0];
			uint32_t id = ops[1];
			uint32_t a = ops[2];
			uint32_t b = ops[3];

			auto &type = get<SPIRType>(result_type);
			string expr = type_to_glsl_constructor(type);
			expr += "(";
			for (uint32_t col = 0; col < type.columns; col++)
			{
				expr += to_enclosed_expression(a);
				expr += " * ";
				expr += to_extract_component_expression(b, col);
				if (col + 1 < type.columns)
					expr += ", ";
			}
			expr += ")";
			emit_op(result_type, id, expr, should_forward(a) && should_forward(b));
			inherit_expression_dependencies(id, a);
			inherit_expression_dependencies(id, b);
		}
		else
			GLSL_BFOP(outerProduct);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDot:
		GLSL_BFOP(dot);
		break;

	case OpTranspose:
#ifndef SPIRV_CROSS_WEBMIN
		if (options.version < 120) // Matches GLSL 1.10 / ESSL 1.00
		{
			// transpose() is not available, so instead, flip need_transpose,
			// which can later be turned into an emulated transpose op by
			// convert_row_major_matrix(), if necessary.
			uint32_t result_type = ops[0];
			uint32_t result_id = ops[1];
			uint32_t input = ops[2];

			// Force need_transpose to false temporarily to prevent
			// to_expression() from doing the transpose.
			bool need_transpose = false;
			auto *input_e = maybe_get<SPIRExpression>(input);
			if (input_e)
				swap(need_transpose, input_e->need_transpose);

			bool forward = should_forward(input);
			auto &e = emit_op(result_type, result_id, to_expression(input), forward);
			e.need_transpose = !need_transpose;

			// Restore the old need_transpose flag.
			if (input_e)
				input_e->need_transpose = need_transpose;
		}
		else
			GLSL_UFOP(transpose);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpSRem:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t result_id = ops[1];
		uint32_t op0 = ops[2];
		uint32_t op1 = ops[3];

		// Needs special handling.
		bool forward = should_forward(op0) && should_forward(op1);
		auto expr = join(to_enclosed_expression(op0), " - ", to_enclosed_expression(op1), " * ", "(",
		                 to_enclosed_expression(op0), " / ", to_enclosed_expression(op1), ")");

		if (implicit_integer_promotion)
			expr = join(type_to_glsl(get<SPIRType>(result_type)), '(', expr, ')');

		emit_op(result_type, result_id, expr, forward);
		inherit_expression_dependencies(result_id, op0);
		inherit_expression_dependencies(result_id, op1);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSDiv:
		GLSL_BOP_CAST(/, int_type);
		break;

	case OpUDiv:
		GLSL_BOP_CAST(/, uint_type);
		break;

	case OpIAddCarry:
	case OpISubBorrow:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (options.es && options.version < 310)
			SPIRV_CROSS_THROW("Extended arithmetic is only available from ESSL 310.");
		else if (!options.es && options.version < 400)
			SPIRV_CROSS_THROW("Extended arithmetic is only available from GLSL 400.");

		uint32_t result_type = ops[0];
		uint32_t result_id = ops[1];
		uint32_t op0 = ops[2];
		uint32_t op1 = ops[3];
		auto &type = get<SPIRType>(result_type);
		emit_uninitialized_temporary_expression(result_type, result_id);
		const char *op = opcode == OpIAddCarry ? "uaddCarry" : "usubBorrow";

		statement(to_expression(result_id), ".", to_member_name(type, 0), " = ", op, "(", to_expression(op0), ", ",
		          to_expression(op1), ", ", to_expression(result_id), ".", to_member_name(type, 1), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpUMulExtended:
	case OpSMulExtended:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (options.es && options.version < 310)
			SPIRV_CROSS_THROW("Extended arithmetic is only available from ESSL 310.");
		else if (!options.es && options.version < 400)
			SPIRV_CROSS_THROW("Extended arithmetic is only available from GLSL 4000.");

		uint32_t result_type = ops[0];
		uint32_t result_id = ops[1];
		uint32_t op0 = ops[2];
		uint32_t op1 = ops[3];
		auto &type = get<SPIRType>(result_type);
		emit_uninitialized_temporary_expression(result_type, result_id);
		const char *op = opcode == OpUMulExtended ? "umulExtended" : "imulExtended";

		statement(op, "(", to_expression(op0), ", ", to_expression(op1), ", ", to_expression(result_id), ".",
		          to_member_name(type, 1), ", ", to_expression(result_id), ".", to_member_name(type, 0), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFDiv:
		GLSL_BOP(/);
		break;

	case OpShiftRightLogical:
		GLSL_BOP_CAST(>>, uint_type);
		break;

	case OpShiftRightArithmetic:
		GLSL_BOP_CAST(>>, int_type);
		break;

	case OpShiftLeftLogical:
	{
		auto type = get<SPIRType>(ops[0]).basetype;
		GLSL_BOP_CAST(<<, type);
		break;
	}

	case OpBitwiseOr:
	{
		auto type = get<SPIRType>(ops[0]).basetype;
		GLSL_BOP_CAST(|, type);
		break;
	}

	case OpBitwiseXor:
	{
		auto type = get<SPIRType>(ops[0]).basetype;
		GLSL_BOP_CAST(^, type);
		break;
	}

	case OpBitwiseAnd:
	{
		auto type = get<SPIRType>(ops[0]).basetype;
		GLSL_BOP_CAST(&, type);
		break;
	}

	case OpNot:
		if (implicit_integer_promotion || expression_type_id(ops[2]) != ops[0])
			GLSL_UOP_CAST(~);
		else
			GLSL_UOP(~);
		break;

	case OpUMod:
		GLSL_BOP_CAST(%, uint_type);
		break;

	case OpSMod:
		GLSL_BOP_CAST(%, int_type);
		break;

	case OpFMod:
		GLSL_BFOP(mod);
		break;

	case OpFRem:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t result_id = ops[1];
		uint32_t op0 = ops[2];
		uint32_t op1 = ops[3];

		// Needs special handling.
		bool forward = should_forward(op0) && should_forward(op1);
		std::string expr;
		if (!is_legacy())
		{
			expr = join(to_enclosed_expression(op0), " - ", to_enclosed_expression(op1), " * ", "trunc(",
			            to_enclosed_expression(op0), " / ", to_enclosed_expression(op1), ")");
		}
		else
		{
			// Legacy GLSL has no trunc, emulate by casting to int and back
			auto &op0_type = expression_type(op0);
			auto via_type = op0_type;
			via_type.basetype = SPIRType::Int;
			expr = join(to_enclosed_expression(op0), " - ", to_enclosed_expression(op1), " * ",
			            type_to_glsl(op0_type), "(", type_to_glsl(via_type),  "(",
			            to_enclosed_expression(op0), " / ", to_enclosed_expression(op1), "))");
		}

		emit_op(result_type, result_id, expr, forward);
		inherit_expression_dependencies(result_id, op0);
		inherit_expression_dependencies(result_id, op1);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Relational
	case OpAny:
		GLSL_UFOP(any);
		break;

	case OpAll:
		GLSL_UFOP(all);
		break;

	case OpSelect:
		emit_mix_op(ops[0], ops[1], ops[4], ops[3], ops[2]);
		break;

	case OpLogicalOr:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// No vector variant in GLSL for logical OR.
		auto result_type = ops[0];
		auto id = ops[1];
		auto &type = get<SPIRType>(result_type);

		if (type.vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "||", false, SPIRType::Unknown);
		else
			GLSL_BOP(||);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpLogicalAnd:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// No vector variant in GLSL for logical AND.
		auto result_type = ops[0];
		auto id = ops[1];
		auto &type = get<SPIRType>(result_type);

		if (type.vecsize > 1)
			emit_unrolled_binary_op(result_type, id, ops[2], ops[3], "&&", false, SPIRType::Unknown);
		else
			GLSL_BOP(&&);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpLogicalNot:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = get<SPIRType>(ops[0]);
		if (type.vecsize > 1)
			GLSL_UFOP(not );
		else
			GLSL_UOP(!);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpIEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP_CAST(equal, int_type);
		else
			GLSL_BOP_CAST(==, int_type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpLogicalEqual:
	case OpFOrdEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP(equal);
		else
			GLSL_BOP(==);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpINotEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP_CAST(notEqual, int_type);
		else
			GLSL_BOP_CAST(!=, int_type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpLogicalNotEqual:
	case OpFOrdNotEqual:
	case OpFUnordNotEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// GLSL is fuzzy on what to do with ordered vs unordered not equal.
		// glslang started emitting UnorderedNotEqual some time ago to harmonize with IEEE,
		// but this means we have no easy way of implementing ordered not equal.
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP(notEqual);
		else
			GLSL_BOP(!=);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpUGreaterThan:
	case OpSGreaterThan:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto type = opcode == OpUGreaterThan ? uint_type : int_type;
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP_CAST(greaterThan, type);
		else
			GLSL_BOP_CAST(>, type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFOrdGreaterThan:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP(greaterThan);
		else
			GLSL_BOP(>);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpUGreaterThanEqual:
	case OpSGreaterThanEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto type = opcode == OpUGreaterThanEqual ? uint_type : int_type;
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP_CAST(greaterThanEqual, type);
		else
			GLSL_BOP_CAST(>=, type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFOrdGreaterThanEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP(greaterThanEqual);
		else
			GLSL_BOP(>=);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpULessThan:
	case OpSLessThan:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto type = opcode == OpULessThan ? uint_type : int_type;
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP_CAST(lessThan, type);
		else
			GLSL_BOP_CAST(<, type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFOrdLessThan:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP(lessThan);
		else
			GLSL_BOP(<);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpULessThanEqual:
	case OpSLessThanEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto type = opcode == OpULessThanEqual ? uint_type : int_type;
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP_CAST(lessThanEqual, type);
		else
			GLSL_BOP_CAST(<=, type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFOrdLessThanEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (expression_type(ops[2]).vecsize > 1)
			GLSL_BFOP(lessThanEqual);
		else
			GLSL_BOP(<=);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Conversion
	case OpSConvert:
	case OpConvertSToF:
	case OpUConvert:
	case OpConvertUToF:
	{
		auto input_type = opcode == OpSConvert || opcode == OpConvertSToF ? int_type : uint_type;
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		auto &type = get<SPIRType>(result_type);
		auto &arg_type = expression_type(ops[2]);
		auto func = type_to_glsl_constructor(type);

		if (arg_type.width < type.width || type_is_floating_point(type))
			emit_unary_func_op_cast(result_type, id, ops[2], func.c_str(), input_type, type.basetype);
		else
			emit_unary_func_op(result_type, id, ops[2], func.c_str());
		break;
	}

	case OpConvertFToU:
	case OpConvertFToS:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// Cast to expected arithmetic type, then potentially bitcast away to desired signedness.
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		auto &type = get<SPIRType>(result_type);
		auto expected_type = type;
		auto &float_type = expression_type(ops[2]);
		expected_type.basetype =
		    opcode == OpConvertFToS ? to_signed_basetype(type.width) : to_unsigned_basetype(type.width);

		auto func = type_to_glsl_constructor(expected_type);
		emit_unary_func_op_cast(result_type, id, ops[2], func.c_str(), float_type.basetype, expected_type.basetype);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFConvert:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		auto func = type_to_glsl_constructor(get<SPIRType>(result_type));
		emit_unary_func_op(result_type, id, ops[2], func.c_str());
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitcast:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t arg = ops[2];

		if (!emit_complex_bitcast(result_type, id, arg))
		{
			auto op = bitcast_glsl_op(get<SPIRType>(result_type), expression_type(arg));
			emit_unary_func_op(result_type, id, arg, op.c_str());
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpQuantizeToF16:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t arg = ops[2];

		string op;
		auto &type = get<SPIRType>(result_type);

		switch (type.vecsize)
		{
		case 1:
			op = join("unpackHalf2x16(packHalf2x16(vec2(", to_expression(arg), "))).x");
			break;
		case 2:
			op = join("unpackHalf2x16(packHalf2x16(", to_expression(arg), "))");
			break;
		case 3:
		{
			auto op0 = join("unpackHalf2x16(packHalf2x16(", to_expression(arg), ".xy))");
			auto op1 = join("unpackHalf2x16(packHalf2x16(", to_expression(arg), ".zz)).x");
			op = join("vec3(", op0, ", ", op1, ")");
			break;
		}
		case 4:
		{
			auto op0 = join("unpackHalf2x16(packHalf2x16(", to_expression(arg), ".xy))");
			auto op1 = join("unpackHalf2x16(packHalf2x16(", to_expression(arg), ".zw))");
			op = join("vec4(", op0, ", ", op1, ")");
			break;
		}
		default:
			SPIRV_CROSS_THROW("Illegal argument to OpQuantizeToF16.");
		}

		emit_op(result_type, id, op, should_forward(arg));
		inherit_expression_dependencies(id, arg);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Derivatives
	case OpDPdx:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(dFdx);
		if (is_legacy_es())
			require_extension_internal("GL_OES_standard_derivatives");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdy:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(dFdy);
		if (is_legacy_es())
			require_extension_internal("GL_OES_standard_derivatives");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdxFine:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(dFdxFine);
		if (options.es)
		{
			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
		}
		if (options.version < 450)
			require_extension_internal("GL_ARB_derivative_control");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdyFine:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(dFdyFine);
		if (options.es)
		{
			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
		}
		if (options.version < 450)
			require_extension_internal("GL_ARB_derivative_control");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdxCoarse:
#ifndef SPIRV_CROSS_WEBMIN
		if (options.es)
		{
			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
		}
		GLSL_UFOP(dFdxCoarse);
		if (options.version < 450)
			require_extension_internal("GL_ARB_derivative_control");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpDPdyCoarse:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(dFdyCoarse);
		if (options.es)
		{
			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
		}
		if (options.version < 450)
			require_extension_internal("GL_ARB_derivative_control");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpFwidth:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(fwidth);
		if (is_legacy_es())
			require_extension_internal("GL_OES_standard_derivatives");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpFwidthCoarse:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(fwidthCoarse);
		if (options.es)
		{
			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
		}
		if (options.version < 450)
			require_extension_internal("GL_ARB_derivative_control");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpFwidthFine:
#ifndef SPIRV_CROSS_WEBMIN
		GLSL_UFOP(fwidthFine);
		if (options.es)
		{
			SPIRV_CROSS_THROW("GL_ARB_derivative_control is unavailable in OpenGL ES.");
		}
		if (options.version < 450)
			require_extension_internal("GL_ARB_derivative_control");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	// Bitfield
	case OpBitFieldInsert:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_bitfield_insert_op(ops[0], ops[1], ops[2], ops[3], ops[4], ops[5], "bitfieldInsert", SPIRType::Int);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitFieldSExtract:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_trinary_func_op_bitextract(ops[0], ops[1], ops[2], ops[3], ops[4], "bitfieldExtract", int_type, int_type,
		                                SPIRType::Int, SPIRType::Int);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitFieldUExtract:
	{
#ifndef SPIRV_CROSS_WEBMIN
		emit_trinary_func_op_bitextract(ops[0], ops[1], ops[2], ops[3], ops[4], "bitfieldExtract", uint_type, uint_type,
		                                SPIRType::Int, SPIRType::Int);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpBitReverse:
#ifndef SPIRV_CROSS_WEBMIN
		// BitReverse does not have issues with sign since result type must match input type.
		GLSL_UFOP(bitfieldReverse);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpBitCount:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto basetype = expression_type(ops[2]).basetype;
		emit_unary_func_op_cast(ops[0], ops[1], ops[2], "bitCount", basetype, int_type);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Atomics
	case OpAtomicExchange:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t ptr = ops[2];
		// Ignore semantics for now, probably only relevant to CL.
		uint32_t val = ops[5];
		const char *op = check_atomic_image(ptr) ? "imageAtomicExchange" : "atomicExchange";

		emit_atomic_func_op(result_type, id, ptr, val, op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicCompareExchange:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t ptr = ops[2];
		uint32_t val = ops[6];
		uint32_t comp = ops[7];
		const char *op = check_atomic_image(ptr) ? "imageAtomicCompSwap" : "atomicCompSwap";

		emit_atomic_func_op(result_type, id, ptr, comp, val, op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicLoad:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// In plain GLSL, we have no atomic loads, so emulate this by fetch adding by 0 and hope compiler figures it out.
		// Alternatively, we could rely on KHR_memory_model, but that's not very helpful for GL.
		auto &type = expression_type(ops[2]);
		forced_temporaries.insert(ops[1]);
		bool atomic_image = check_atomic_image(ops[2]);
		bool unsigned_type = (type.basetype == SPIRType::UInt) ||
		                     (atomic_image && get<SPIRType>(type.image.type).basetype == SPIRType::UInt);
		const char *op = atomic_image ? "imageAtomicAdd" : "atomicAdd";
		const char *increment = unsigned_type ? "0u" : "0";
		emit_op(ops[0], ops[1],
		        join(op, "(",
		             to_non_uniform_aware_expression(ops[2]), ", ", increment, ")"), false);
		flush_all_atomic_capable_variables();
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicStore:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// In plain GLSL, we have no atomic stores, so emulate this with an atomic exchange where we don't consume the result.
		// Alternatively, we could rely on KHR_memory_model, but that's not very helpful for GL.
		uint32_t ptr = ops[0];
		// Ignore semantics for now, probably only relevant to CL.
		uint32_t val = ops[3];
		const char *op = check_atomic_image(ptr) ? "imageAtomicExchange" : "atomicExchange";
		statement(op, "(", to_non_uniform_aware_expression(ptr), ", ", to_expression(val), ");");
		flush_all_atomic_capable_variables();
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicIIncrement:
	case OpAtomicIDecrement:
	{
#ifndef SPIRV_CROSS_WEBMIN
		forced_temporaries.insert(ops[1]);
		auto &type = expression_type(ops[2]);
		if (type.storage == StorageClassAtomicCounter)
		{
			// Legacy GLSL stuff, not sure if this is relevant to support.
			if (opcode == OpAtomicIIncrement)
				GLSL_UFOP(atomicCounterIncrement);
			else
				GLSL_UFOP(atomicCounterDecrement);
		}
		else
		{
			bool atomic_image = check_atomic_image(ops[2]);
			bool unsigned_type = (type.basetype == SPIRType::UInt) ||
			                     (atomic_image && get<SPIRType>(type.image.type).basetype == SPIRType::UInt);
			const char *op = atomic_image ? "imageAtomicAdd" : "atomicAdd";

			const char *increment = nullptr;
			if (opcode == OpAtomicIIncrement && unsigned_type)
				increment = "1u";
			else if (opcode == OpAtomicIIncrement)
				increment = "1";
			else if (unsigned_type)
				increment = "uint(-1)";
			else
				increment = "-1";

			emit_op(ops[0], ops[1],
			        join(op, "(", to_non_uniform_aware_expression(ops[2]), ", ", increment, ")"), false);
		}

		flush_all_atomic_capable_variables();
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicIAdd:
	case OpAtomicFAddEXT:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = check_atomic_image(ops[2]) ? "imageAtomicAdd" : "atomicAdd";
		emit_atomic_func_op(ops[0], ops[1], ops[2], ops[5], op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicISub:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = check_atomic_image(ops[2]) ? "imageAtomicAdd" : "atomicAdd";
		forced_temporaries.insert(ops[1]);
		auto expr = join(op, "(", to_non_uniform_aware_expression(ops[2]), ", -", to_enclosed_expression(ops[5]), ")");
		emit_op(ops[0], ops[1], expr, should_forward(ops[2]) && should_forward(ops[5]));
		flush_all_atomic_capable_variables();
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicSMin:
	case OpAtomicUMin:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = check_atomic_image(ops[2]) ? "imageAtomicMin" : "atomicMin";
		emit_atomic_func_op(ops[0], ops[1], ops[2], ops[5], op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicSMax:
	case OpAtomicUMax:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = check_atomic_image(ops[2]) ? "imageAtomicMax" : "atomicMax";
		emit_atomic_func_op(ops[0], ops[1], ops[2], ops[5], op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicAnd:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = check_atomic_image(ops[2]) ? "imageAtomicAnd" : "atomicAnd";
		emit_atomic_func_op(ops[0], ops[1], ops[2], ops[5], op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicOr:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = check_atomic_image(ops[2]) ? "imageAtomicOr" : "atomicOr";
		emit_atomic_func_op(ops[0], ops[1], ops[2], ops[5], op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpAtomicXor:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = check_atomic_image(ops[2]) ? "imageAtomicXor" : "atomicXor";
		emit_atomic_func_op(ops[0], ops[1], ops[2], ops[5], op);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Geometry shaders
	case OpEmitVertex:
#ifndef SPIRV_CROSS_WEBMIN
		statement("EmitVertex();");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpEndPrimitive:
#ifndef SPIRV_CROSS_WEBMIN
		statement("EndPrimitive();");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpEmitStreamVertex:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (options.es)
			SPIRV_CROSS_THROW("Multi-stream geometry shaders not supported in ES.");
		else if (!options.es && options.version < 400)
			SPIRV_CROSS_THROW("Multi-stream geometry shaders only supported in GLSL 400.");

		auto stream_expr = to_expression(ops[0]);
		if (expression_type(ops[0]).basetype != SPIRType::Int)
			stream_expr = join("int(", stream_expr, ")");
		statement("EmitStreamVertex(", stream_expr, ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpEndStreamPrimitive:
	{
#ifndef SPIRV_CROSS_WEBMIN
		if (options.es)
			SPIRV_CROSS_THROW("Multi-stream geometry shaders not supported in ES.");
		else if (!options.es && options.version < 400)
			SPIRV_CROSS_THROW("Multi-stream geometry shaders only supported in GLSL 400.");

		auto stream_expr = to_expression(ops[0]);
		if (expression_type(ops[0]).basetype != SPIRType::Int)
			stream_expr = join("int(", stream_expr, ")");
		statement("EndStreamPrimitive(", stream_expr, ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Textures
	case OpImageSampleExplicitLod:
	case OpImageSampleProjExplicitLod:
	case OpImageSampleDrefExplicitLod:
	case OpImageSampleProjDrefExplicitLod:
	case OpImageSampleImplicitLod:
	case OpImageSampleProjImplicitLod:
	case OpImageSampleDrefImplicitLod:
	case OpImageSampleProjDrefImplicitLod:
	case OpImageFetch:
	case OpImageGather:
	case OpImageDrefGather:
		// Gets a bit hairy, so move this to a separate instruction.
		emit_texture_op(instruction, false);
		break;

	case OpImageSparseSampleExplicitLod:
	case OpImageSparseSampleProjExplicitLod:
	case OpImageSparseSampleDrefExplicitLod:
	case OpImageSparseSampleProjDrefExplicitLod:
	case OpImageSparseSampleImplicitLod:
	case OpImageSparseSampleProjImplicitLod:
	case OpImageSparseSampleDrefImplicitLod:
	case OpImageSparseSampleProjDrefImplicitLod:
	case OpImageSparseFetch:
	case OpImageSparseGather:
	case OpImageSparseDrefGather:
#ifndef SPIRV_CROSS_WEBMIN
		// Gets a bit hairy, so move this to a separate instruction.
		emit_texture_op(instruction, true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpImageSparseTexelsResident:
#ifndef SPIRV_CROSS_WEBMIN
		if (options.es)
			SPIRV_CROSS_THROW("Sparse feedback is not supported in GLSL.");
		require_extension_internal("GL_ARB_sparse_texture2");
		emit_unary_func_op_cast(ops[0], ops[1], ops[2], "sparseTexelsResidentARB", int_type, SPIRType::Boolean);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpImage:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		// Suppress usage tracking.
		auto &e = emit_op(result_type, id, to_expression(ops[2]), true, true);

		// When using the image, we need to know which variable it is actually loaded from.
		auto *var = maybe_get_backing_variable(ops[2]);
		e.loaded_from = var ? var->self : ID(0);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageQueryLod:
	{
#ifndef SPIRV_CROSS_WEBMIN
		const char *op = nullptr;
		if (!options.es && options.version < 400)
		{
			require_extension_internal("GL_ARB_texture_query_lod");
			// For some reason, the ARB spec is all-caps.
			op = "textureQueryLOD";
		}
		else if (options.es)
		{
			if (options.version < 300)
				SPIRV_CROSS_THROW("textureQueryLod not supported in legacy ES");
			require_extension_internal("GL_EXT_texture_query_lod");
			op = "textureQueryLOD";
		}
		else
			op = "textureQueryLod";

		auto sampler_expr = to_expression(ops[2]);
		if (has_decoration(ops[2], DecorationNonUniform))
		{
			if (maybe_get_backing_variable(ops[2]))
				convert_non_uniform_expression(sampler_expr, ops[2]);
			else if (*backend.nonuniform_qualifier != '\0')
				sampler_expr = join(backend.nonuniform_qualifier, "(", sampler_expr, ")");
		}

		bool forward = should_forward(ops[3]);
		emit_op(ops[0], ops[1],
		        join(op, "(", sampler_expr, ", ", to_unpacked_expression(ops[3]), ")"),
		        forward);
		inherit_expression_dependencies(ops[1], ops[2]);
		inherit_expression_dependencies(ops[1], ops[3]);
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageQueryLevels:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		if (!options.es && options.version < 430)
			require_extension_internal("GL_ARB_texture_query_levels");
		if (options.es)
			SPIRV_CROSS_THROW("textureQueryLevels not supported in ES profile.");

		auto expr = join("textureQueryLevels(", convert_separate_image_to_expression(ops[2]), ")");
		auto &restype = get<SPIRType>(ops[0]);
		expr = bitcast_expression(restype, SPIRType::Int, expr);
		emit_op(result_type, id, expr, true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageQuerySamples:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = expression_type(ops[2]);
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		if (options.es)
			SPIRV_CROSS_THROW("textureSamples and imageSamples not supported in ES profile.");
		else if (options.version < 450)
			require_extension_internal("GL_ARB_texture_query_samples");

		string expr;
		if (type.image.sampled == 2)
			expr = join("imageSamples(", to_non_uniform_aware_expression(ops[2]), ")");
		else
			expr = join("textureSamples(", convert_separate_image_to_expression(ops[2]), ")");

		auto &restype = get<SPIRType>(ops[0]);
		expr = bitcast_expression(restype, SPIRType::Int, expr);
		emit_op(result_type, id, expr, true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSampledImage:
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_sampled_image_op(result_type, id, ops[2], ops[3]);
		inherit_expression_dependencies(id, ops[2]);
		inherit_expression_dependencies(id, ops[3]);
		break;
	}

	case OpImageQuerySizeLod:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		uint32_t img = ops[2];
		auto &type = expression_type(img);
		auto &imgtype = get<SPIRType>(type.self);

		std::string fname = "textureSize";
		if (is_legacy_desktop())
		{
			fname = legacy_tex_op(fname, imgtype, img);
		}
		else if (is_legacy_es())
			SPIRV_CROSS_THROW("textureSize is not supported in ESSL 100.");

		auto expr = join(fname, "(", convert_separate_image_to_expression(img), ", ",
		                 bitcast_expression(SPIRType::Int, ops[3]), ")");

		// ES needs to emulate 1D images as 2D.
		if (type.image.dim == Dim1D && options.es)
			expr = join(expr, ".x");

		auto &restype = get<SPIRType>(ops[0]);
		expr = bitcast_expression(restype, SPIRType::Int, expr);
		emit_op(result_type, id, expr, true);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Image load/store
	case OpImageRead:
	case OpImageSparseRead:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// We added Nonreadable speculatively to the OpImage variable due to glslangValidator
		// not adding the proper qualifiers.
		// If it turns out we need to read the image after all, remove the qualifier and recompile.
		auto *var = maybe_get_backing_variable(ops[2]);
		if (var)
		{
			auto &flags = get_decoration_bitset(var->self);
			if (flags.get(DecorationNonReadable))
			{
				unset_decoration(var->self, DecorationNonReadable);
				force_recompile();
			}
		}

		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		bool pure;
		string imgexpr;
		auto &type = expression_type(ops[2]);

		if (var && var->remapped_variable) // Remapped input, just read as-is without any op-code
		{
			if (type.image.ms)
				SPIRV_CROSS_THROW("Trying to remap multisampled image to variable, this is not possible.");

			auto itr =
			    find_if(begin(pls_inputs), end(pls_inputs), [var](const PlsRemap &pls) { return pls.id == var->self; });

			if (itr == end(pls_inputs))
			{
				// For non-PLS inputs, we rely on subpass type remapping information to get it right
				// since ImageRead always returns 4-component vectors and the backing type is opaque.
				if (!var->remapped_components)
					SPIRV_CROSS_THROW("subpassInput was remapped, but remap_components is not set correctly.");
				imgexpr = remap_swizzle(get<SPIRType>(result_type), var->remapped_components, to_expression(ops[2]));
			}
			else
			{
				// PLS input could have different number of components than what the SPIR expects, swizzle to
				// the appropriate vector size.
				uint32_t components = pls_format_to_components(itr->format);
				imgexpr = remap_swizzle(get<SPIRType>(result_type), components, to_expression(ops[2]));
			}
			pure = true;
		}
		else if (type.image.dim == DimSubpassData)
		{
			if (var && subpass_input_is_framebuffer_fetch(var->self))
			{
				imgexpr = to_expression(var->self);
			}
			else if (options.vulkan_semantics)
			{
				// With Vulkan semantics, use the proper Vulkan GLSL construct.
				if (type.image.ms)
				{
					uint32_t operands = ops[4];
					if (operands != ImageOperandsSampleMask || length != 6)
						SPIRV_CROSS_THROW("Multisampled image used in OpImageRead, but unexpected "
						                  "operand mask was used.");

					uint32_t samples = ops[5];
					imgexpr = join("subpassLoad(", to_non_uniform_aware_expression(ops[2]), ", ", to_expression(samples), ")");
				}
				else
					imgexpr = join("subpassLoad(", to_non_uniform_aware_expression(ops[2]), ")");
			}
			else
			{
				if (type.image.ms)
				{
					uint32_t operands = ops[4];
					if (operands != ImageOperandsSampleMask || length != 6)
						SPIRV_CROSS_THROW("Multisampled image used in OpImageRead, but unexpected "
						                  "operand mask was used.");

					uint32_t samples = ops[5];
					imgexpr = join("texelFetch(", to_non_uniform_aware_expression(ops[2]), ", ivec2(gl_FragCoord.xy), ",
					               to_expression(samples), ")");
				}
				else
				{
					// Implement subpass loads via texture barrier style sampling.
					imgexpr = join("texelFetch(", to_non_uniform_aware_expression(ops[2]), ", ivec2(gl_FragCoord.xy), 0)");
				}
			}
			imgexpr = remap_swizzle(get<SPIRType>(result_type), 4, imgexpr);
			pure = true;
		}
		else
		{
			bool sparse = opcode == OpImageSparseRead;
			uint32_t sparse_code_id = 0;
			uint32_t sparse_texel_id = 0;
			if (sparse)
				emit_sparse_feedback_temporaries(ops[0], ops[1], sparse_code_id, sparse_texel_id);

			// imageLoad only accepts int coords, not uint.
			auto coord_expr = to_expression(ops[3]);
			auto target_coord_type = expression_type(ops[3]);
			target_coord_type.basetype = SPIRType::Int;
			coord_expr = bitcast_expression(target_coord_type, expression_type(ops[3]).basetype, coord_expr);

			// ES needs to emulate 1D images as 2D.
			if (type.image.dim == Dim1D && options.es)
				coord_expr = join("ivec2(", coord_expr, ", 0)");

			// Plain image load/store.
			if (sparse)
			{
				if (type.image.ms)
				{
					uint32_t operands = ops[4];
					if (operands != ImageOperandsSampleMask || length != 6)
						SPIRV_CROSS_THROW("Multisampled image used in OpImageRead, but unexpected "
						                  "operand mask was used.");

					uint32_t samples = ops[5];
					statement(to_expression(sparse_code_id), " = sparseImageLoadARB(", to_non_uniform_aware_expression(ops[2]), ", ",
					          coord_expr, ", ", to_expression(samples), ", ", to_expression(sparse_texel_id), ");");
				}
				else
				{
					statement(to_expression(sparse_code_id), " = sparseImageLoadARB(", to_non_uniform_aware_expression(ops[2]), ", ",
					          coord_expr, ", ", to_expression(sparse_texel_id), ");");
				}
				imgexpr = join(type_to_glsl(get<SPIRType>(result_type)), "(", to_expression(sparse_code_id), ", ",
				               to_expression(sparse_texel_id), ")");
			}
			else
			{
				if (type.image.ms)
				{
					uint32_t operands = ops[4];
					if (operands != ImageOperandsSampleMask || length != 6)
						SPIRV_CROSS_THROW("Multisampled image used in OpImageRead, but unexpected "
						                  "operand mask was used.");

					uint32_t samples = ops[5];
					imgexpr =
					    join("imageLoad(", to_non_uniform_aware_expression(ops[2]), ", ", coord_expr, ", ", to_expression(samples), ")");
				}
				else
					imgexpr = join("imageLoad(", to_non_uniform_aware_expression(ops[2]), ", ", coord_expr, ")");
			}

			if (!sparse)
				imgexpr = remap_swizzle(get<SPIRType>(result_type), 4, imgexpr);
			pure = false;
		}

		if (var)
		{
			bool forward = forced_temporaries.find(id) == end(forced_temporaries);
			auto &e = emit_op(result_type, id, imgexpr, forward);

			// We only need to track dependencies if we're reading from image load/store.
			if (!pure)
			{
				e.loaded_from = var->self;
				if (forward)
					var->dependees.push_back(id);
			}
		}
		else
			emit_op(result_type, id, imgexpr, false);

		inherit_expression_dependencies(id, ops[2]);
		if (type.image.ms)
			inherit_expression_dependencies(id, ops[5]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageTexelPointer:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		auto coord_expr = to_expression(ops[3]);
		auto target_coord_type = expression_type(ops[3]);
		target_coord_type.basetype = SPIRType::Int;
		coord_expr = bitcast_expression(target_coord_type, expression_type(ops[3]).basetype, coord_expr);

		auto expr = join(to_expression(ops[2]), ", ", coord_expr);
		auto &e = set<SPIRExpression>(id, expr, result_type, true);

		// When using the pointer, we need to know which variable it is actually loaded from.
		auto *var = maybe_get_backing_variable(ops[2]);
		e.loaded_from = var ? var->self : ID(0);
		inherit_expression_dependencies(id, ops[3]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageWrite:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// We added Nonwritable speculatively to the OpImage variable due to glslangValidator
		// not adding the proper qualifiers.
		// If it turns out we need to write to the image after all, remove the qualifier and recompile.
		auto *var = maybe_get_backing_variable(ops[0]);
		if (var)
		{
			if (has_decoration(var->self, DecorationNonWritable))
			{
				unset_decoration(var->self, DecorationNonWritable);
				force_recompile();
			}
		}

		auto &type = expression_type(ops[0]);
		auto &value_type = expression_type(ops[2]);
		auto store_type = value_type;
		store_type.vecsize = 4;

		// imageStore only accepts int coords, not uint.
		auto coord_expr = to_expression(ops[1]);
		auto target_coord_type = expression_type(ops[1]);
		target_coord_type.basetype = SPIRType::Int;
		coord_expr = bitcast_expression(target_coord_type, expression_type(ops[1]).basetype, coord_expr);

		// ES needs to emulate 1D images as 2D.
		if (type.image.dim == Dim1D && options.es)
			coord_expr = join("ivec2(", coord_expr, ", 0)");

		if (type.image.ms)
		{
			uint32_t operands = ops[3];
			if (operands != ImageOperandsSampleMask || length != 5)
				SPIRV_CROSS_THROW("Multisampled image used in OpImageWrite, but unexpected operand mask was used.");
			uint32_t samples = ops[4];
			statement("imageStore(", to_non_uniform_aware_expression(ops[0]), ", ", coord_expr, ", ", to_expression(samples), ", ",
			          remap_swizzle(store_type, value_type.vecsize, to_expression(ops[2])), ");");
		}
		else
			statement("imageStore(", to_non_uniform_aware_expression(ops[0]), ", ", coord_expr, ", ",
			          remap_swizzle(store_type, value_type.vecsize, to_expression(ops[2])), ");");

		if (var && variable_storage_is_aliased(*var))
			flush_all_aliased_variables();
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpImageQuerySize:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = expression_type(ops[2]);
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		if (type.basetype == SPIRType::Image)
		{
			string expr;
			if (type.image.sampled == 2)
			{
				if (!options.es && options.version < 430)
					require_extension_internal("GL_ARB_shader_image_size");
				else if (options.es && options.version < 310)
					SPIRV_CROSS_THROW("At least ESSL 3.10 required for imageSize.");

				// The size of an image is always constant.
				expr = join("imageSize(", to_non_uniform_aware_expression(ops[2]), ")");
			}
			else
			{
				// This path is hit for samplerBuffers and multisampled images which do not have LOD.
				std::string fname = "textureSize";
				if (is_legacy())
				{
					auto &imgtype = get<SPIRType>(type.self);
					fname = legacy_tex_op(fname, imgtype, ops[2]);
				}
				expr = join(fname, "(", convert_separate_image_to_expression(ops[2]), ")");
			}

			auto &restype = get<SPIRType>(ops[0]);
			expr = bitcast_expression(restype, SPIRType::Int, expr);
			emit_op(result_type, id, expr, true);
		}
		else
			SPIRV_CROSS_THROW("Invalid type for OpImageQuerySize.");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Compute
	case OpControlBarrier:
	case OpMemoryBarrier:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t execution_scope = 0;
		uint32_t memory;
		uint32_t semantics;

		if (opcode == OpMemoryBarrier)
		{
			memory = evaluate_constant_u32(ops[0]);
			semantics = evaluate_constant_u32(ops[1]);
		}
		else
		{
			execution_scope = evaluate_constant_u32(ops[0]);
			memory = evaluate_constant_u32(ops[1]);
			semantics = evaluate_constant_u32(ops[2]);
		}

		if (execution_scope == ScopeSubgroup || memory == ScopeSubgroup)
		{
			// OpControlBarrier with ScopeSubgroup is subgroupBarrier()
			if (opcode != OpControlBarrier)
			{
				request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupMemBarrier);
			}
			else
			{
				request_subgroup_feature(ShaderSubgroupSupportHelper::SubgroupBarrier);
			}
		}

		if (execution_scope != ScopeSubgroup && get_entry_point().model == ExecutionModelTessellationControl)
		{
			// Control shaders only have barriers, and it implies memory barriers.
			if (opcode == OpControlBarrier)
				statement("barrier();");
			break;
		}

		// We only care about these flags, acquire/release and friends are not relevant to GLSL.
		semantics = mask_relevant_memory_semantics(semantics);

		if (opcode == OpMemoryBarrier)
		{
			// If we are a memory barrier, and the next instruction is a control barrier, check if that memory barrier
			// does what we need, so we avoid redundant barriers.
			const Instruction *next = get_next_instruction_in_block(instruction);
			if (next && next->op == OpControlBarrier)
			{
				auto *next_ops = stream(*next);
				uint32_t next_memory = evaluate_constant_u32(next_ops[1]);
				uint32_t next_semantics = evaluate_constant_u32(next_ops[2]);
				next_semantics = mask_relevant_memory_semantics(next_semantics);

				bool memory_scope_covered = false;
				if (next_memory == memory)
					memory_scope_covered = true;
				else if (next_semantics == MemorySemanticsWorkgroupMemoryMask)
				{
					// If we only care about workgroup memory, either Device or Workgroup scope is fine,
					// scope does not have to match.
					if ((next_memory == ScopeDevice || next_memory == ScopeWorkgroup) &&
					    (memory == ScopeDevice || memory == ScopeWorkgroup))
					{
						memory_scope_covered = true;
					}
				}
				else if (memory == ScopeWorkgroup && next_memory == ScopeDevice)
				{
					// The control barrier has device scope, but the memory barrier just has workgroup scope.
					memory_scope_covered = true;
				}

				// If we have the same memory scope, and all memory types are covered, we're good.
				if (memory_scope_covered && (semantics & next_semantics) == semantics)
					break;
			}
		}

		// We are synchronizing some memory or syncing execution,
		// so we cannot forward any loads beyond the memory barrier.
		if (semantics || opcode == OpControlBarrier)
		{
			assert(current_emitting_block);
			flush_control_dependent_expressions(current_emitting_block->self);
			flush_all_active_variables();
		}

		if (memory == ScopeWorkgroup) // Only need to consider memory within a group
		{
			if (semantics == MemorySemanticsWorkgroupMemoryMask)
			{
				// OpControlBarrier implies a memory barrier for shared memory as well.
				bool implies_shared_barrier = opcode == OpControlBarrier && execution_scope == ScopeWorkgroup;
				if (!implies_shared_barrier)
					statement("memoryBarrierShared();");
			}
			else if (semantics != 0)
				statement("groupMemoryBarrier();");
		}
		else if (memory == ScopeSubgroup)
		{
			const uint32_t all_barriers =
			    MemorySemanticsWorkgroupMemoryMask | MemorySemanticsUniformMemoryMask | MemorySemanticsImageMemoryMask;

			if (semantics & (MemorySemanticsCrossWorkgroupMemoryMask | MemorySemanticsSubgroupMemoryMask))
			{
				// These are not relevant for GLSL, but assume it means memoryBarrier().
				// memoryBarrier() does everything, so no need to test anything else.
				statement("subgroupMemoryBarrier();");
			}
			else if ((semantics & all_barriers) == all_barriers)
			{
				// Short-hand instead of emitting 3 barriers.
				statement("subgroupMemoryBarrier();");
			}
			else
			{
				// Pick out individual barriers.
				if (semantics & MemorySemanticsWorkgroupMemoryMask)
					statement("subgroupMemoryBarrierShared();");
				if (semantics & MemorySemanticsUniformMemoryMask)
					statement("subgroupMemoryBarrierBuffer();");
				if (semantics & MemorySemanticsImageMemoryMask)
					statement("subgroupMemoryBarrierImage();");
			}
		}
		else
		{
			const uint32_t all_barriers =
			    MemorySemanticsWorkgroupMemoryMask | MemorySemanticsUniformMemoryMask | MemorySemanticsImageMemoryMask;

			if (semantics & (MemorySemanticsCrossWorkgroupMemoryMask | MemorySemanticsSubgroupMemoryMask))
			{
				// These are not relevant for GLSL, but assume it means memoryBarrier().
				// memoryBarrier() does everything, so no need to test anything else.
				statement("memoryBarrier();");
			}
			else if ((semantics & all_barriers) == all_barriers)
			{
				// Short-hand instead of emitting 4 barriers.
				statement("memoryBarrier();");
			}
			else
			{
				// Pick out individual barriers.
				if (semantics & MemorySemanticsWorkgroupMemoryMask)
					statement("memoryBarrierShared();");
				if (semantics & MemorySemanticsUniformMemoryMask)
					statement("memoryBarrierBuffer();");
				if (semantics & MemorySemanticsImageMemoryMask)
					statement("memoryBarrierImage();");
			}
		}

		if (opcode == OpControlBarrier)
		{
			if (execution_scope == ScopeSubgroup)
				statement("subgroupBarrier();");
			else
				statement("barrier();");
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpExtInst:
	{
		uint32_t extension_set = ops[2];
		auto ext = get<SPIRExtension>(extension_set).ext;

		if (ext == SPIRExtension::GLSL)
		{
			emit_glsl_op(ops[0], ops[1], ops[3], &ops[4], length - 4);
		}
		else if (ext == SPIRExtension::SPV_AMD_shader_ballot)
		{
			emit_spv_amd_shader_ballot_op(ops[0], ops[1], ops[3], &ops[4], length - 4);
		}
		else if (ext == SPIRExtension::SPV_AMD_shader_explicit_vertex_parameter)
		{
			emit_spv_amd_shader_explicit_vertex_parameter_op(ops[0], ops[1], ops[3], &ops[4], length - 4);
		}
		else if (ext == SPIRExtension::SPV_AMD_shader_trinary_minmax)
		{
			emit_spv_amd_shader_trinary_minmax_op(ops[0], ops[1], ops[3], &ops[4], length - 4);
		}
		else if (ext == SPIRExtension::SPV_AMD_gcn_shader)
		{
			emit_spv_amd_gcn_shader_op(ops[0], ops[1], ops[3], &ops[4], length - 4);
		}
		else if (ext == SPIRExtension::SPV_debug_info ||
		         ext == SPIRExtension::NonSemanticShaderDebugInfo ||
		         ext == SPIRExtension::NonSemanticGeneric)
		{
			break; // Ignore SPIR-V debug information extended instructions.
		}
		else if (ext == SPIRExtension::NonSemanticDebugPrintf)
		{
			// Operation 1 is printf.
			if (ops[3] == 1)
			{
				if (!options.vulkan_semantics)
					SPIRV_CROSS_THROW("Debug printf is only supported in Vulkan GLSL.\n");
				require_extension_internal("GL_EXT_debug_printf");
				auto &format_string = get<SPIRString>(ops[4]).str;
				string expr = join("debugPrintfEXT(\"", format_string, "\"");
				for (uint32_t i = 5; i < length; i++)
				{
					expr += ", ";
					expr += to_expression(ops[i]);
				}
				statement(expr, ");");
			}
		}
		else
		{
			statement("// unimplemented ext op ", instruction.op);
			break;
		}

		break;
	}

	// Legacy sub-group stuff ...
	case OpSubgroupBallotKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		string expr;
		expr = join("uvec4(unpackUint2x32(ballotARB(" + to_expression(ops[2]) + ")), 0u, 0u)");
		emit_op(result_type, id, expr, should_forward(ops[2]));

		require_extension_internal("GL_ARB_shader_ballot");
		inherit_expression_dependencies(id, ops[2]);
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSubgroupFirstInvocationKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_unary_func_op(result_type, id, ops[2], "readFirstInvocationARB");

		require_extension_internal("GL_ARB_shader_ballot");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSubgroupReadInvocationKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_binary_func_op(result_type, id, ops[2], ops[3], "readInvocationARB");

		require_extension_internal("GL_ARB_shader_ballot");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSubgroupAllKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_unary_func_op(result_type, id, ops[2], "allInvocationsARB");

		require_extension_internal("GL_ARB_shader_group_vote");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSubgroupAnyKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_unary_func_op(result_type, id, ops[2], "anyInvocationARB");

		require_extension_internal("GL_ARB_shader_group_vote");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpSubgroupAllEqualKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_unary_func_op(result_type, id, ops[2], "allInvocationsEqualARB");

		require_extension_internal("GL_ARB_shader_group_vote");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpGroupIAddNonUniformAMD:
	case OpGroupFAddNonUniformAMD:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_unary_func_op(result_type, id, ops[4], "addInvocationsNonUniformAMD");

		require_extension_internal("GL_AMD_shader_ballot");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpGroupFMinNonUniformAMD:
	case OpGroupUMinNonUniformAMD:
	case OpGroupSMinNonUniformAMD:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_unary_func_op(result_type, id, ops[4], "minInvocationsNonUniformAMD");

		require_extension_internal("GL_AMD_shader_ballot");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpGroupFMaxNonUniformAMD:
	case OpGroupUMaxNonUniformAMD:
	case OpGroupSMaxNonUniformAMD:
	{
#ifndef SPIRV_CROSS_WEBMIN
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		emit_unary_func_op(result_type, id, ops[4], "maxInvocationsNonUniformAMD");

		require_extension_internal("GL_AMD_shader_ballot");
		register_control_dependent_expression(ops[1]);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFragmentMaskFetchAMD:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = expression_type(ops[2]);
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		if (type.image.dim == spv::DimSubpassData)
		{
			emit_unary_func_op(result_type, id, ops[2], "fragmentMaskFetchAMD");
		}
		else
		{
			emit_binary_func_op(result_type, id, ops[2], ops[3], "fragmentMaskFetchAMD");
		}

		require_extension_internal("GL_AMD_shader_fragment_mask");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpFragmentFetchAMD:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = expression_type(ops[2]);
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];

		if (type.image.dim == spv::DimSubpassData)
		{
			emit_binary_func_op(result_type, id, ops[2], ops[4], "fragmentFetchAMD");
		}
		else
		{
			emit_trinary_func_op(result_type, id, ops[2], ops[3], ops[4], "fragmentFetchAMD");
		}

		require_extension_internal("GL_AMD_shader_fragment_mask");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	// Vulkan 1.1 sub-group stuff ...
	case OpGroupNonUniformElect:
	case OpGroupNonUniformBroadcast:
	case OpGroupNonUniformBroadcastFirst:
	case OpGroupNonUniformBallot:
	case OpGroupNonUniformInverseBallot:
	case OpGroupNonUniformBallotBitExtract:
	case OpGroupNonUniformBallotBitCount:
	case OpGroupNonUniformBallotFindLSB:
	case OpGroupNonUniformBallotFindMSB:
	case OpGroupNonUniformShuffle:
	case OpGroupNonUniformShuffleXor:
	case OpGroupNonUniformShuffleUp:
	case OpGroupNonUniformShuffleDown:
	case OpGroupNonUniformAll:
	case OpGroupNonUniformAny:
	case OpGroupNonUniformAllEqual:
	case OpGroupNonUniformFAdd:
	case OpGroupNonUniformIAdd:
	case OpGroupNonUniformFMul:
	case OpGroupNonUniformIMul:
	case OpGroupNonUniformFMin:
	case OpGroupNonUniformFMax:
	case OpGroupNonUniformSMin:
	case OpGroupNonUniformSMax:
	case OpGroupNonUniformUMin:
	case OpGroupNonUniformUMax:
	case OpGroupNonUniformBitwiseAnd:
	case OpGroupNonUniformBitwiseOr:
	case OpGroupNonUniformBitwiseXor:
	case OpGroupNonUniformLogicalAnd:
	case OpGroupNonUniformLogicalOr:
	case OpGroupNonUniformLogicalXor:
	case OpGroupNonUniformQuadSwap:
	case OpGroupNonUniformQuadBroadcast:
#ifndef SPIRV_CROSS_WEBMIN
		emit_subgroup_op(instruction);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpFUnordEqual:
	case OpFUnordLessThan:
	case OpFUnordGreaterThan:
	case OpFUnordLessThanEqual:
	case OpFUnordGreaterThanEqual:
	{
#ifndef SPIRV_CROSS_WEBMIN
		// GLSL doesn't specify if floating point comparisons are ordered or unordered,
		// but glslang always emits ordered floating point compares for GLSL.
		// To get unordered compares, we can test the opposite thing and invert the result.
		// This way, we force true when there is any NaN present.
		uint32_t op0 = ops[2];
		uint32_t op1 = ops[3];

		string expr;
		if (expression_type(op0).vecsize > 1)
		{
			const char *comp_op = nullptr;
			switch (opcode)
			{
			case OpFUnordEqual:
				comp_op = "notEqual";
				break;

			case OpFUnordLessThan:
				comp_op = "greaterThanEqual";
				break;

			case OpFUnordLessThanEqual:
				comp_op = "greaterThan";
				break;

			case OpFUnordGreaterThan:
				comp_op = "lessThanEqual";
				break;

			case OpFUnordGreaterThanEqual:
				comp_op = "lessThan";
				break;

			default:
				assert(0);
				break;
			}

			expr = join("not(", comp_op, "(", to_unpacked_expression(op0), ", ", to_unpacked_expression(op1), "))");
		}
		else
		{
			const char *comp_op = nullptr;
			switch (opcode)
			{
			case OpFUnordEqual:
				comp_op = " != ";
				break;

			case OpFUnordLessThan:
				comp_op = " >= ";
				break;

			case OpFUnordLessThanEqual:
				comp_op = " > ";
				break;

			case OpFUnordGreaterThan:
				comp_op = " <= ";
				break;

			case OpFUnordGreaterThanEqual:
				comp_op = " < ";
				break;

			default:
				assert(0);
				break;
			}

			expr = join("!(", to_enclosed_unpacked_expression(op0), comp_op, to_enclosed_unpacked_expression(op1), ")");
		}

		emit_op(ops[0], ops[1], expr, should_forward(op0) && should_forward(op1));
		inherit_expression_dependencies(ops[1], op0);
		inherit_expression_dependencies(ops[1], op1);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpReportIntersectionKHR:
#ifndef SPIRV_CROSS_WEBMIN
		// NV is same opcode.
		forced_temporaries.insert(ops[1]);
		if (ray_tracing_is_khr)
			GLSL_BFOP(reportIntersectionEXT);
		else
			GLSL_BFOP(reportIntersectionNV);
		flush_control_dependent_expressions(current_emitting_block->self);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpIgnoreIntersectionNV:
#ifndef SPIRV_CROSS_WEBMIN
		// KHR variant is a terminator.
		statement("ignoreIntersectionNV();");
		flush_control_dependent_expressions(current_emitting_block->self);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpTerminateRayNV:
#ifndef SPIRV_CROSS_WEBMIN
		// KHR variant is a terminator.
		statement("terminateRayNV();");
		flush_control_dependent_expressions(current_emitting_block->self);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpTraceNV:
#ifndef SPIRV_CROSS_WEBMIN
		statement("traceNV(", to_non_uniform_aware_expression(ops[0]), ", ", to_expression(ops[1]), ", ", to_expression(ops[2]), ", ",
		          to_expression(ops[3]), ", ", to_expression(ops[4]), ", ", to_expression(ops[5]), ", ",
		          to_expression(ops[6]), ", ", to_expression(ops[7]), ", ", to_expression(ops[8]), ", ",
		          to_expression(ops[9]), ", ", to_expression(ops[10]), ");");
		flush_control_dependent_expressions(current_emitting_block->self);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpTraceRayKHR:
#ifndef SPIRV_CROSS_WEBMIN
		if (!has_decoration(ops[10], DecorationLocation))
			SPIRV_CROSS_THROW("A memory declaration object must be used in TraceRayKHR.");
		statement("traceRayEXT(", to_non_uniform_aware_expression(ops[0]), ", ", to_expression(ops[1]), ", ", to_expression(ops[2]), ", ",
		          to_expression(ops[3]), ", ", to_expression(ops[4]), ", ", to_expression(ops[5]), ", ",
		          to_expression(ops[6]), ", ", to_expression(ops[7]), ", ", to_expression(ops[8]), ", ",
		          to_expression(ops[9]), ", ", get_decoration(ops[10], DecorationLocation), ");");
		flush_control_dependent_expressions(current_emitting_block->self);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpExecuteCallableNV:
#ifndef SPIRV_CROSS_WEBMIN
		statement("executeCallableNV(", to_expression(ops[0]), ", ", to_expression(ops[1]), ");");
		flush_control_dependent_expressions(current_emitting_block->self);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpExecuteCallableKHR:
#ifndef SPIRV_CROSS_WEBMIN
		if (!has_decoration(ops[1], DecorationLocation))
			SPIRV_CROSS_THROW("A memory declaration object must be used in ExecuteCallableKHR.");
		statement("executeCallableEXT(", to_expression(ops[0]), ", ", get_decoration(ops[1], DecorationLocation), ");");
		flush_control_dependent_expressions(current_emitting_block->self);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

		// Don't bother forwarding temporaries. Avoids having to test expression invalidation with ray query objects.
	case OpRayQueryInitializeKHR:
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		statement("rayQueryInitializeEXT(",
		          to_expression(ops[0]), ", ", to_expression(ops[1]), ", ",
		          to_expression(ops[2]), ", ", to_expression(ops[3]), ", ",
		          to_expression(ops[4]), ", ", to_expression(ops[5]), ", ",
		          to_expression(ops[6]), ", ", to_expression(ops[7]), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpRayQueryProceedKHR:
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		emit_op(ops[0], ops[1], join("rayQueryProceedEXT(", to_expression(ops[2]), ")"), false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpRayQueryTerminateKHR:
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		statement("rayQueryTerminateEXT(", to_expression(ops[0]), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpRayQueryGenerateIntersectionKHR:
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		statement("rayQueryGenerateIntersectionEXT(", to_expression(ops[0]), ", ", to_expression(ops[1]), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	case OpRayQueryConfirmIntersectionKHR:
#ifndef SPIRV_CROSS_WEBMIN
		flush_variable_declaration(ops[0]);
		statement("rayQueryConfirmIntersectionEXT(", to_expression(ops[0]), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
#define GLSL_RAY_QUERY_GET_OP(op) \
	case OpRayQueryGet##op##KHR: \
		flush_variable_declaration(ops[2]); \
		emit_op(ops[0], ops[1], join("rayQueryGet" #op "EXT(", to_expression(ops[2]), ")"), false); \
		break
#define GLSL_RAY_QUERY_GET_OP2(op) \
	case OpRayQueryGet##op##KHR: \
		flush_variable_declaration(ops[2]); \
		emit_op(ops[0], ops[1], join("rayQueryGet" #op "EXT(", to_expression(ops[2]), ", ", "bool(", to_expression(ops[3]), "))"), false); \
		break
	GLSL_RAY_QUERY_GET_OP(RayTMin);
	GLSL_RAY_QUERY_GET_OP(RayFlags);
	GLSL_RAY_QUERY_GET_OP(WorldRayOrigin);
	GLSL_RAY_QUERY_GET_OP(WorldRayDirection);
	GLSL_RAY_QUERY_GET_OP(IntersectionCandidateAABBOpaque);
	GLSL_RAY_QUERY_GET_OP2(IntersectionType);
	GLSL_RAY_QUERY_GET_OP2(IntersectionT);
	GLSL_RAY_QUERY_GET_OP2(IntersectionInstanceCustomIndex);
	GLSL_RAY_QUERY_GET_OP2(IntersectionInstanceId);
	GLSL_RAY_QUERY_GET_OP2(IntersectionInstanceShaderBindingTableRecordOffset);
	GLSL_RAY_QUERY_GET_OP2(IntersectionGeometryIndex);
	GLSL_RAY_QUERY_GET_OP2(IntersectionPrimitiveIndex);
	GLSL_RAY_QUERY_GET_OP2(IntersectionBarycentrics);
	GLSL_RAY_QUERY_GET_OP2(IntersectionFrontFace);
	GLSL_RAY_QUERY_GET_OP2(IntersectionObjectRayDirection);
	GLSL_RAY_QUERY_GET_OP2(IntersectionObjectRayOrigin);
	GLSL_RAY_QUERY_GET_OP2(IntersectionObjectToWorld);
	GLSL_RAY_QUERY_GET_OP2(IntersectionWorldToObject);
#undef GLSL_RAY_QUERY_GET_OP
#undef GLSL_RAY_QUERY_GET_OP2

	case OpConvertUToAccelerationStructureKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		require_extension_internal("GL_EXT_ray_tracing");

		bool elide_temporary = should_forward(ops[2]) && forced_temporaries.count(ops[1]) == 0 &&
		                       !hoisted_temporaries.count(ops[1]);

		if (elide_temporary)
		{
			GLSL_UFOP(accelerationStructureEXT);
		}
		else
		{
			// Force this path in subsequent iterations.
			forced_temporaries.insert(ops[1]);

			// We cannot declare a temporary acceleration structure in GLSL.
			// If we get to this point, we'll have to emit a temporary uvec2,
			// and cast to RTAS on demand.
			statement(declare_temporary(expression_type_id(ops[2]), ops[1]), to_unpacked_expression(ops[2]), ";");
			// Use raw SPIRExpression interface to block all usage tracking.
			set<SPIRExpression>(ops[1], join("accelerationStructureEXT(", to_name(ops[1]), ")"), ops[0], true);
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpConvertUToPtr:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = get<SPIRType>(ops[0]);
		if (type.storage != StorageClassPhysicalStorageBufferEXT)
			SPIRV_CROSS_THROW("Only StorageClassPhysicalStorageBufferEXT is supported by OpConvertUToPtr.");

		auto &in_type = expression_type(ops[2]);
		if (in_type.vecsize == 2)
			require_extension_internal("GL_EXT_buffer_reference_uvec2");

		auto op = type_to_glsl(type);
		emit_unary_func_op(ops[0], ops[1], ops[2], op.c_str());
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpConvertPtrToU:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = get<SPIRType>(ops[0]);
		auto &ptr_type = expression_type(ops[2]);
		if (ptr_type.storage != StorageClassPhysicalStorageBufferEXT)
			SPIRV_CROSS_THROW("Only StorageClassPhysicalStorageBufferEXT is supported by OpConvertPtrToU.");

		if (type.vecsize == 2)
			require_extension_internal("GL_EXT_buffer_reference_uvec2");

		auto op = type_to_glsl(type);
		emit_unary_func_op(ops[0], ops[1], ops[2], op.c_str());
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	case OpUndef:
		// Undefined value has been declared.
		break;

	case OpLine:
	{
		emit_line_directive(ops[0], ops[1]);
		break;
	}

	case OpNoLine:
		break;

	case OpDemoteToHelperInvocationEXT:
#ifndef SPIRV_CROSS_WEBMIN
		if (!options.vulkan_semantics)
			SPIRV_CROSS_THROW("GL_EXT_demote_to_helper_invocation is only supported in Vulkan GLSL.");
		require_extension_internal("GL_EXT_demote_to_helper_invocation");
		statement(backend.demote_literal, ";");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpIsHelperInvocationEXT:
#ifndef SPIRV_CROSS_WEBMIN
		if (!options.vulkan_semantics)
			SPIRV_CROSS_THROW("GL_EXT_demote_to_helper_invocation is only supported in Vulkan GLSL.");
		require_extension_internal("GL_EXT_demote_to_helper_invocation");
		// Helper lane state with demote is volatile by nature.
		// Do not forward this.
		emit_op(ops[0], ops[1], "helperInvocationEXT()", false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpBeginInvocationInterlockEXT:
#ifndef SPIRV_CROSS_WEBMIN
		// If the interlock is complex, we emit this elsewhere.
		if (!interlocked_is_complex)
		{
			statement("SPIRV_Cross_beginInvocationInterlock();");
			flush_all_active_variables();
			// Make sure forwarding doesn't propagate outside interlock region.
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpEndInvocationInterlockEXT:
#ifndef SPIRV_CROSS_WEBMIN
		// If the interlock is complex, we emit this elsewhere.
		if (!interlocked_is_complex)
		{
			statement("SPIRV_Cross_endInvocationInterlock();");
			flush_all_active_variables();
			// Make sure forwarding doesn't propagate outside interlock region.
		}
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpSetMeshOutputsEXT:
#ifndef SPIRV_CROSS_WEBMIN
		statement("SetMeshOutputsEXT(", to_unpacked_expression(ops[0]), ", ", to_unpacked_expression(ops[1]), ");");
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;

	case OpReadClockKHR:
	{
#ifndef SPIRV_CROSS_WEBMIN
		auto &type = get<SPIRType>(ops[0]);
		auto scope = static_cast<Scope>(evaluate_constant_u32(ops[2]));
		const char *op = nullptr;
		// Forwarding clock statements leads to a scenario where an SSA value can take on different
		// values every time it's evaluated. Block any forwarding attempt.
		// We also might want to invalidate all expressions to function as a sort of optimization
		// barrier, but might be overkill for now.
		if (scope == ScopeDevice)
		{
			require_extension_internal("GL_EXT_shader_realtime_clock");
			if (type.basetype == SPIRType::BaseType::UInt64)
				op = "clockRealtimeEXT()";
			else if (type.basetype == SPIRType::BaseType::UInt && type.vecsize == 2)
				op = "clockRealtime2x32EXT()";
			else
				SPIRV_CROSS_THROW("Unsupported result type for OpReadClockKHR opcode.");
		}
		else if (scope == ScopeSubgroup)
		{
			require_extension_internal("GL_ARB_shader_clock");
			if (type.basetype == SPIRType::BaseType::UInt64)
				op = "clockARB()";
			else if (type.basetype == SPIRType::BaseType::UInt && type.vecsize == 2)
				op = "clock2x32ARB()";
			else
				SPIRV_CROSS_THROW("Unsupported result type for OpReadClockKHR opcode.");
		}
		else
			SPIRV_CROSS_THROW("Unsupported scope for OpReadClockKHR opcode.");

		emit_op(ops[0], ops[1], op, false);
#else
		SPIRV_CROSS_INVALID_CALL();
#endif
		break;
	}

	default:
		statement("// unimplemented op ", instruction.op);
		break;
	}
}

void CompilerHLSL::cast_from_variable_load(uint32_t source_id, std::string &expr, const SPIRType &expr_type)
{
	// We will handle array cases elsewhere.
	if (!expr_type.array.empty())
		return;

	auto *var = maybe_get_backing_variable(source_id);
	if (var)
		source_id = var->self;

	// Only interested in standalone builtin variables.
	if (!has_decoration(source_id, DecorationBuiltIn))
	{
		// Except for int attributes in legacy GLSL, which are cast from float.
		if (is_legacy() && expr_type.basetype == SPIRType::Int && var && var->storage == StorageClassInput)
			expr = join(type_to_glsl(expr_type), "(", expr, ")");
		return;
	}

	auto builtin = static_cast<BuiltIn>(get_decoration(source_id, DecorationBuiltIn));
	auto expected_type = expr_type.basetype;

	// TODO: Fill in for more builtins.
	switch (builtin)
	{
	case BuiltInLayer:
	case BuiltInPrimitiveId:
	case BuiltInViewportIndex:
	case BuiltInInstanceId:
	case BuiltInInstanceIndex:
	case BuiltInVertexId:
	case BuiltInVertexIndex:
	case BuiltInSampleId:
	case BuiltInBaseVertex:
	case BuiltInBaseInstance:
	case BuiltInDrawIndex:
	case BuiltInFragStencilRefEXT:
	case BuiltInInstanceCustomIndexNV:
	case BuiltInSampleMask:
	case BuiltInPrimitiveShadingRateKHR:
	case BuiltInShadingRateKHR:
		expected_type = SPIRType::Int;
		break;

	case BuiltInGlobalInvocationId:
	case BuiltInLocalInvocationId:
	case BuiltInWorkgroupId:
	case BuiltInLocalInvocationIndex:
	case BuiltInWorkgroupSize:
	case BuiltInNumWorkgroups:
	case BuiltInIncomingRayFlagsNV:
	case BuiltInLaunchIdNV:
	case BuiltInLaunchSizeNV:
	case BuiltInPrimitiveTriangleIndicesEXT:
	case BuiltInPrimitiveLineIndicesEXT:
	case BuiltInPrimitivePointIndicesEXT:
		expected_type = SPIRType::UInt;
		break;

	default:
		break;
	}

	if (expected_type != expr_type.basetype)
		expr = bitcast_expression(expr_type, expected_type, expr);
}

void CompilerHLSL::unroll_array_from_complex_load(uint32_t target_id, uint32_t source_id, std::string &expr)
{
	if (!backend.force_gl_in_out_block)
		return;
	// This path is only relevant for GL backends.

	auto *var = maybe_get<SPIRVariable>(source_id);
	if (!var)
		return;

	if (var->storage != StorageClassInput && var->storage != StorageClassOutput)
		return;

	auto &type = get_variable_data_type(*var);
	if (type.array.empty())
		return;

	auto builtin = BuiltIn(get_decoration(var->self, DecorationBuiltIn));
	bool is_builtin = is_builtin_variable(*var) &&
	                  (builtin == BuiltInPointSize ||
	                   builtin == BuiltInPosition ||
	                   builtin == BuiltInSampleMask);
	bool is_tess = is_tessellation_shader();
	bool is_patch = has_decoration(var->self, DecorationPatch);
	bool is_sample_mask = is_builtin && builtin == BuiltInSampleMask;

	// Tessellation input arrays are special in that they are unsized, so we cannot directly copy from it.
	// We must unroll the array load.
	// For builtins, we couldn't catch this case normally,
	// because this is resolved in the OpAccessChain in most cases.
	// If we load the entire array, we have no choice but to unroll here.
	if (!is_patch && (is_builtin || is_tess))
	{
		auto new_expr = join("_", target_id, "_unrolled");
		statement(variable_decl(type, new_expr, target_id), ";");
		string array_expr;
		if (type.array_size_literal.back())
		{
			array_expr = convert_to_string(type.array.back());
			if (type.array.back() == 0)
				SPIRV_CROSS_THROW("Cannot unroll an array copy from unsized array.");
		}
		else
			array_expr = to_expression(type.array.back());

		// The array size might be a specialization constant, so use a for-loop instead.
		statement("for (int i = 0; i < int(", array_expr, "); i++)");
		begin_scope();
		if (is_builtin && !is_sample_mask)
			statement(new_expr, "[i] = gl_in[i].", expr, ";");
		else if (is_sample_mask)
		{
			SPIRType target_type;
			target_type.basetype = SPIRType::Int;
			statement(new_expr, "[i] = ", bitcast_expression(target_type, type.basetype, join(expr, "[i]")), ";");
		}
		else
			statement(new_expr, "[i] = ", expr, "[i];");
		end_scope();

		expr = std::move(new_expr);
	}
}

bool CompilerHLSL::expression_is_non_value_type_array(uint32_t ptr)
{
	auto &type = expression_type(ptr);
	if (!type_is_top_level_array(get_pointee_type(type)))
		return false;

	if (!backend.array_is_value_type)
		return true;

	auto *var = maybe_get_backing_variable(ptr);
	if (!var)
		return false;

	auto &backed_type = get<SPIRType>(var->basetype);
	return !backend.array_is_value_type_in_buffer_blocks && backed_type.basetype == SPIRType::Struct &&
	       has_member_decoration(backed_type.self, 0, DecorationOffset);
}

void CompilerHLSL::register_call_out_argument(uint32_t id)
{
	register_write(id);

	auto *var = maybe_get<SPIRVariable>(id);
	if (var)
		flush_variable_declaration(var->self);
}

void CompilerHLSL::emit_mix_op(uint32_t result_type, uint32_t id, uint32_t left, uint32_t right, uint32_t lerp)
{
	auto &lerptype = expression_type(lerp);
	auto &restype = get<SPIRType>(result_type);

	// If this results in a variable pointer, assume it may be written through.
	if (restype.pointer)
	{
		register_write(left);
		register_write(right);
	}

	string mix_op;
	bool has_boolean_mix = *backend.boolean_mix_function &&
	                       ((options.es && options.version >= 310) || (!options.es && options.version >= 450));
	bool trivial_mix = to_trivial_mix_op(restype, mix_op, left, right, lerp);

	// Cannot use boolean mix when the lerp argument is just one boolean,
	// fall back to regular trinary statements.
	if (lerptype.vecsize == 1)
		has_boolean_mix = false;

	// If we can reduce the mix to a simple cast, do so.
	// This helps for cases like int(bool), uint(bool) which is implemented with
	// OpSelect bool 1 0.
	if (trivial_mix)
	{
		emit_unary_func_op(result_type, id, lerp, mix_op.c_str());
	}
	else if (!has_boolean_mix && lerptype.basetype == SPIRType::Boolean)
	{
		// Boolean mix not supported on desktop without extension.
		// Was added in OpenGL 4.5 with ES 3.1 compat.
		//
		// Could use GL_EXT_shader_integer_mix on desktop at least,
		// but Apple doesn't support it. :(
		// Just implement it as ternary expressions.
		auto expr = to_ternary_expression(get<SPIRType>(result_type), lerp, right, left);
		emit_op(result_type, id, expr, should_forward(left) && should_forward(right) && should_forward(lerp));
		inherit_expression_dependencies(id, left);
		inherit_expression_dependencies(id, right);
		inherit_expression_dependencies(id, lerp);
	}
	else if (lerptype.basetype == SPIRType::Boolean)
		emit_trinary_func_op(result_type, id, left, right, lerp, backend.boolean_mix_function);
	else
		emit_trinary_func_op(result_type, id, left, right, lerp, "mix");
}

void CompilerHLSL::emit_store_statement(uint32_t lhs_expression, uint32_t rhs_expression)
{
	auto rhs = to_pointer_expression(rhs_expression);

	// Statements to OpStore may be empty if it is a struct with zero members. Just forward the store to /dev/null.
	if (!rhs.empty())
	{
		handle_store_to_invariant_variable(lhs_expression, rhs_expression);

		if (!unroll_array_to_complex_store(lhs_expression, rhs_expression))
		{
			auto lhs = to_dereferenced_expression(lhs_expression);
			if (has_decoration(lhs_expression, DecorationNonUniform))
				convert_non_uniform_expression(lhs, lhs_expression);

			// We might need to cast in order to store to a builtin.
			cast_to_variable_store(lhs_expression, rhs, expression_type(rhs_expression));

			// Tries to optimize assignments like "<lhs> = <lhs> op expr".
			// While this is purely cosmetic, this is important for legacy ESSL where loop
			// variable increments must be in either i++ or i += const-expr.
			// Without this, we end up with i = i + 1, which is correct GLSL, but not correct GLES 2.0.
			if (!optimize_read_modify_write(expression_type(rhs_expression), lhs, rhs))
				statement(lhs, " = ", rhs, ";");
		}
		register_write(lhs_expression);
	}
}

void CompilerHLSL::handle_store_to_invariant_variable(uint32_t store_id, uint32_t value_id)
{
	// Variables or access chains marked invariant are complicated. We will need to make sure the code-gen leading up to
	// this variable is consistent. The failure case for SPIRV-Cross is when an expression is forced to a temporary
	// in one translation unit, but not another, e.g. due to multiple use of an expression.
	// This causes variance despite the output variable being marked invariant, so the solution here is to force all dependent
	// expressions to be temporaries.
	// It is uncertain if this is enough to support invariant in all possible cases, but it should be good enough
	// for all reasonable uses of invariant.
	if (!has_decoration(store_id, DecorationInvariant))
		return;

	auto *expr = maybe_get<SPIRExpression>(value_id);
	if (!expr)
		return;

	disallow_forwarding_in_expression_chain(*expr);
}

bool CompilerHLSL::unroll_array_to_complex_store(uint32_t target_id, uint32_t source_id)
{
	if (!backend.force_gl_in_out_block)
		return false;
	// This path is only relevant for GL backends.

	auto *var = maybe_get<SPIRVariable>(target_id);
	if (!var || var->storage != StorageClassOutput)
		return false;

	if (!is_builtin_variable(*var) || BuiltIn(get_decoration(var->self, DecorationBuiltIn)) != BuiltInSampleMask)
		return false;

	auto &type = expression_type(source_id);
	string array_expr;
	if (type.array_size_literal.back())
	{
		array_expr = convert_to_string(type.array.back());
		if (type.array.back() == 0)
			SPIRV_CROSS_THROW("Cannot unroll an array copy from unsized array.");
	}
	else
		array_expr = to_expression(type.array.back());

	SPIRType target_type;
	target_type.basetype = SPIRType::Int;

	statement("for (int i = 0; i < int(", array_expr, "); i++)");
	begin_scope();
	statement(to_expression(target_id), "[i] = ",
	          bitcast_expression(target_type, type.basetype, join(to_expression(source_id), "[i]")),
	          ";");
	end_scope();

	return true;
}

void CompilerHLSL::cast_to_variable_store(uint32_t target_id, std::string &expr, const SPIRType &expr_type)
{
	auto *var = maybe_get_backing_variable(target_id);
	if (var)
		target_id = var->self;

	// Only interested in standalone builtin variables.
	if (!has_decoration(target_id, DecorationBuiltIn))
		return;

	auto builtin = static_cast<BuiltIn>(get_decoration(target_id, DecorationBuiltIn));
	auto expected_type = expr_type.basetype;

	// TODO: Fill in for more builtins.
	switch (builtin)
	{
	case BuiltInLayer:
	case BuiltInPrimitiveId:
	case BuiltInViewportIndex:
	case BuiltInFragStencilRefEXT:
	case BuiltInSampleMask:
	case BuiltInPrimitiveShadingRateKHR:
	case BuiltInShadingRateKHR:
		expected_type = SPIRType::Int;
		break;

	default:
		break;
	}

	if (expected_type != expr_type.basetype)
	{
		auto type = expr_type;
		type.basetype = expected_type;
		expr = bitcast_expression(type, expr_type.basetype, expr);
	}
}

void CompilerHLSL::register_impure_function_call()
{
	// Impure functions can modify globals and aliased variables, so invalidate them as well.
	for (auto global : global_variables)
		flush_dependees(get<SPIRVariable>(global));
	for (auto aliased : aliased_variables)
		flush_dependees(get<SPIRVariable>(aliased));
}

void CompilerHLSL::append_global_func_args(const SPIRFunction &func, uint32_t index, SmallVector<string> &arglist)
{
	auto &args = func.arguments;
	uint32_t arg_cnt = uint32_t(args.size());
	for (uint32_t arg_idx = index; arg_idx < arg_cnt; arg_idx++)
	{
		auto &arg = args[arg_idx];
		assert(arg.alias_global_variable);

		// If the underlying variable needs to be declared
		// (ie. a local variable with deferred declaration), do so now.
		uint32_t var_id = get<SPIRVariable>(arg.id).basevariable;
		if (var_id)
			flush_variable_declaration(var_id);

		arglist.push_back(to_func_call_arg(arg, arg.id));
	}
}

void CompilerHLSL::check_function_call_constraints(const uint32_t *args, uint32_t length)
{
	// If our variable is remapped, and we rely on type-remapping information as
	// well, then we cannot pass the variable as a function parameter.
	// Fixing this is non-trivial without stamping out variants of the same function,
	// so for now warn about this and suggest workarounds instead.
	for (uint32_t i = 0; i < length; i++)
	{
		auto *var = maybe_get<SPIRVariable>(args[i]);
		if (!var || !var->remapped_variable)
			continue;

		auto &type = get<SPIRType>(var->basetype);
		if (type.basetype == SPIRType::Image && type.image.dim == DimSubpassData)
		{
			SPIRV_CROSS_THROW("Tried passing a remapped subpassInput variable to a function. "
			                  "This will not work correctly because type-remapping information is lost. "
			                  "To workaround, please consider not passing the subpass input as a function parameter, "
			                  "or use in/out variables instead which do not need type remapping information.");
		}
	}
}

bool CompilerHLSL::args_will_forward(uint32_t id, const uint32_t *args, uint32_t num_args, bool pure)
{
	if (forced_temporaries.find(id) != end(forced_temporaries))
		return false;

	for (uint32_t i = 0; i < num_args; i++)
		if (!should_forward(args[i]))
			return false;

	// We need to forward globals as well.
	if (!pure)
	{
		for (auto global : global_variables)
			if (!should_forward(global))
				return false;
		for (auto aliased : aliased_variables)
			if (!should_forward(aliased))
				return false;
	}

	return true;
}

string CompilerHLSL::build_composite_combiner(uint32_t return_type, const uint32_t *elems, uint32_t length)
{
	ID base = 0;
	string op;
	string subop;

	// Can only merge swizzles for vectors.
	auto &type = get<SPIRType>(return_type);
	bool can_apply_swizzle_opt = type.basetype != SPIRType::Struct && type.array.empty() && type.columns == 1;
	bool swizzle_optimization = false;

	for (uint32_t i = 0; i < length; i++)
	{
		auto *e = maybe_get<SPIRExpression>(elems[i]);

		// If we're merging another scalar which belongs to the same base
		// object, just merge the swizzles to avoid triggering more than 1 expression read as much as possible!
		if (can_apply_swizzle_opt && e && e->base_expression && e->base_expression == base)
		{
			// Only supposed to be used for vector swizzle -> scalar.
			assert(!e->expression.empty() && e->expression.front() == '.');
			subop += e->expression.substr(1, string::npos);
			swizzle_optimization = true;
		}
		else
		{
			// We'll likely end up with duplicated swizzles, e.g.
			// foobar.xyz.xyz from patterns like
			// OpVectorShuffle
			// OpCompositeExtract x 3
			// OpCompositeConstruct 3x + other scalar.
			// Just modify op in-place.
			if (swizzle_optimization)
			{
				if (backend.swizzle_is_function)
					subop += "()";

				// Don't attempt to remove unity swizzling if we managed to remove duplicate swizzles.
				// The base "foo" might be vec4, while foo.xyz is vec3 (OpVectorShuffle) and looks like a vec3 due to the .xyz tacked on.
				// We only want to remove the swizzles if we're certain that the resulting base will be the same vecsize.
				// Essentially, we can only remove one set of swizzles, since that's what we have control over ...
				// Case 1:
				//  foo.yxz.xyz: Duplicate swizzle kicks in, giving foo.yxz, we are done.
				//               foo.yxz was the result of OpVectorShuffle and we don't know the type of foo.
				// Case 2:
				//  foo.xyz: Duplicate swizzle won't kick in.
				//           If foo is vec3, we can remove xyz, giving just foo.
				if (!remove_duplicate_swizzle(subop))
					remove_unity_swizzle(base, subop);

				// Strips away redundant parens if we created them during component extraction.
				strip_enclosed_expression(subop);
				swizzle_optimization = false;
				op += subop;
			}
			else
				op += subop;

			if (i)
				op += ", ";

			bool uses_buffer_offset =
			    type.basetype == SPIRType::Struct && has_member_decoration(type.self, i, DecorationOffset);
			subop = to_composite_constructor_expression(type, elems[i], uses_buffer_offset);
		}

		base = e ? e->base_expression : ID(0);
	}

	if (swizzle_optimization)
	{
		if (backend.swizzle_is_function)
			subop += "()";

		if (!remove_duplicate_swizzle(subop))
			remove_unity_swizzle(base, subop);
		// Strips away redundant parens if we created them during component extraction.
		strip_enclosed_expression(subop);
	}

	op += subop;
	return op;
}

// Optimizes away vector swizzles where we have something like
// vec3 foo;
// foo.xyz <-- swizzle expression does nothing.
// This is a very common pattern after OpCompositeCombine.
bool CompilerHLSL::remove_unity_swizzle(uint32_t base, string &op)
{
	auto pos = op.find_last_of('.');
	if (pos == string::npos || pos == 0)
		return false;

	string final_swiz = op.substr(pos + 1, string::npos);

	if (backend.swizzle_is_function)
	{
		if (final_swiz.size() < 2)
			return false;

		if (final_swiz.substr(final_swiz.size() - 2, string::npos) == "()")
			final_swiz.erase(final_swiz.size() - 2, string::npos);
		else
			return false;
	}

	// Check if final swizzle is of form .x, .xy, .xyz, .xyzw or similar.
	// If so, and previous swizzle is of same length,
	// we can drop the final swizzle altogether.
	for (uint32_t i = 0; i < final_swiz.size(); i++)
	{
		static const char expected[] = { 'x', 'y', 'z', 'w' };
		if (i >= 4 || final_swiz[i] != expected[i])
			return false;
	}

	auto &type = expression_type(base);

	// Sanity checking ...
	assert(type.columns == 1 && type.array.empty());

	if (type.vecsize == final_swiz.size())
		op.erase(pos, string::npos);
	return true;
}

string CompilerHLSL::to_composite_constructor_expression(const SPIRType &parent_type, uint32_t id, bool block_like_type)
{
	auto &type = expression_type(id);

	bool reroll_array = false;
	bool remapped_boolean = parent_type.basetype == SPIRType::Struct &&
	                        type.basetype == SPIRType::Boolean &&
	                        backend.boolean_in_struct_remapped_type != SPIRType::Boolean;

	if (type_is_top_level_array(type))
	{
		reroll_array = !backend.array_is_value_type ||
		               (block_like_type && !backend.array_is_value_type_in_buffer_blocks);

		if (remapped_boolean)
		{
			// Forced to reroll if we have to change bool[] to short[].
			reroll_array = true;
		}
	}

	if (reroll_array)
	{
		// For this case, we need to "re-roll" an array initializer from a temporary.
		// We cannot simply pass the array directly, since it decays to a pointer and it cannot
		// participate in a struct initializer. E.g.
		// float arr[2] = { 1.0, 2.0 };
		// Foo foo = { arr }; must be transformed to
		// Foo foo = { { arr[0], arr[1] } };
		// The array sizes cannot be deduced from specialization constants since we cannot use any loops.

		// We're only triggering one read of the array expression, but this is fine since arrays have to be declared
		// as temporaries anyways.
		return to_rerolled_array_expression(parent_type, to_enclosed_expression(id), type);
	}
	else
	{
		auto expr = to_unpacked_expression(id);
		if (remapped_boolean)
		{
			auto tmp_type = type;
			tmp_type.basetype = backend.boolean_in_struct_remapped_type;
			expr = join(type_to_glsl(tmp_type), "(", expr, ")");
		}

		return expr;
	}
}

bool CompilerHLSL::should_suppress_usage_tracking(uint32_t id) const
{
	// Used only by opcodes which don't do any real "work", they just swizzle data in some fashion.
	return !expression_is_forwarded(id) || expression_suppresses_usage_tracking(id);
}

#ifndef SPIRV_CROSS_WEBMIN
CompilerHLSL::ShaderSubgroupSupportHelper::Result::Result()
{
	for (auto &weight : weights)
		weight = 0;

	// Make sure KHR_shader_subgroup extensions are always prefered.
	const uint32_t big_num = FeatureCount;
	weights[KHR_shader_subgroup_ballot] = big_num;
	weights[KHR_shader_subgroup_basic] = big_num;
	weights[KHR_shader_subgroup_vote] = big_num;
	weights[KHR_shader_subgroup_arithmetic] = big_num;
}

string CompilerHLSL::image_type_hlsl_legacy(const SPIRType &type, uint32_t /*id*/)
{
	auto &imagetype = get<SPIRType>(type.image.type);
	string res;

	switch (imagetype.basetype)
	{
	case SPIRType::Int:
		res = "i";
		break;
	case SPIRType::UInt:
		res = "u";
		break;
	default:
		break;
	}

	if (type.basetype == SPIRType::Image && type.image.dim == DimSubpassData)
		return res + "subpassInput" + (type.image.ms ? "MS" : "");

	// If we're emulating subpassInput with samplers, force sampler2D
	// so we don't have to specify format.
	if (type.basetype == SPIRType::Image && type.image.dim != DimSubpassData)
	{
		// Sampler buffers are always declared as samplerBuffer even though they might be separate images in the SPIR-V.
		if (type.image.dim == DimBuffer && type.image.sampled == 1)
			res += "sampler";
		else
			res += type.image.sampled == 2 ? "image" : "texture";
	}
	else
		res += "sampler";

	switch (type.image.dim)
	{
	case Dim1D:
		res += "1D";
		break;
	case Dim2D:
		res += "2D";
		break;
	case Dim3D:
		res += "3D";
		break;
	case DimCube:
		res += "CUBE";
		break;

	case DimBuffer:
		res += "Buffer";
		break;

	case DimSubpassData:
		res += "2D";
		break;
	default:
		SPIRV_CROSS_THROW("Only 1D, 2D, 3D, Buffer, InputTarget and Cube textures supported.");
	}

	if (type.image.ms)
		res += "MS";
	if (type.image.arrayed)
		res += "Array";

	return res;
}

string CompilerHLSL::image_type_hlsl(const SPIRType &type, uint32_t id)
{
	if (hlsl_options.shader_model <= 30)
		return image_type_hlsl_legacy(type, id);
	else
		return image_type_hlsl_modern(type, id);
}

std::string CompilerHLSL::to_initializer_expression(const SPIRVariable &var)
{
	// We cannot emit static const initializer for block constants for practical reasons,
	// so just inline the initializer.
	// FIXME: There is a theoretical problem here if someone tries to composite extract
	// into this initializer since we don't declare it properly, but that is somewhat non-sensical.
	auto &type = get<SPIRType>(var.basetype);
	bool is_block = has_decoration(type.self, DecorationBlock);
	auto *c = maybe_get<SPIRConstant>(var.initializer);
	if (is_block && c)
		return constant_expression(*c);
	else
		return CompilerGLSL_to_initializer_expression(var);
}

void CompilerHLSL::emit_interface_block_member_in_struct(const SPIRVariable &var, uint32_t member_index,
                                                         uint32_t location,
                                                         std::unordered_set<uint32_t> &active_locations)
{
	auto &execution = get_entry_point();
	auto type = get<SPIRType>(var.basetype);
	auto semantic = to_semantic(location, execution.model, var.storage);
	auto mbr_name = join(to_name(type.self), "_", to_member_name(type, member_index));
	auto &mbr_type = get<SPIRType>(type.member_types[member_index]);

	statement(to_interpolation_qualifiers(get_member_decoration_bitset(type.self, member_index)),
	          type_to_glsl(mbr_type),
	          " ", mbr_name, type_to_array_glsl(mbr_type),
	          " : ", semantic, ";");

	// Structs and arrays should consume more locations.
	uint32_t consumed_locations = type_to_consumed_locations(mbr_type);
	for (uint32_t i = 0; i < consumed_locations; i++)
		active_locations.insert(location + i);
}

void CompilerHLSL::set_hlsl_aux_buffer_binding(HLSLAuxBinding binding, uint32_t register_index, uint32_t register_space)
{
	if (binding == HLSL_AUX_BINDING_BASE_VERTEX_INSTANCE)
	{
		base_vertex_info.explicit_binding = true;
		base_vertex_info.register_space = register_space;
		base_vertex_info.register_index = register_index;
	}
}

void CompilerHLSL::unset_hlsl_aux_buffer_binding(HLSLAuxBinding binding)
{
	if (binding == HLSL_AUX_BINDING_BASE_VERTEX_INSTANCE)
		base_vertex_info.explicit_binding = false;
}

bool CompilerHLSL::is_hlsl_aux_buffer_binding_used(HLSLAuxBinding binding) const
{
	if (binding == HLSL_AUX_BINDING_BASE_VERTEX_INSTANCE)
		return base_vertex_info.used;
	else
		return false;
}

void CompilerHLSL::analyze_meshlet_writes()
{
	uint32_t id_per_vertex = 0;
	uint32_t id_per_primitive = 0;
	bool need_per_primitive = false;
	bool need_per_vertex = false;

	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);
		bool block = has_decoration(type.self, DecorationBlock);
		if (var.storage == StorageClassOutput && block && is_builtin_variable(var))
		{
			auto flags = get_buffer_block_flags(var.self);
			if (flags.get(DecorationPerPrimitiveEXT))
				id_per_primitive = var.self;
			else
				id_per_vertex = var.self;
		}
		else if (var.storage == StorageClassOutput)
		{
			Bitset flags;
			if (block)
				flags = get_buffer_block_flags(var.self);
			else
				flags = get_decoration_bitset(var.self);

			if (flags.get(DecorationPerPrimitiveEXT))
				need_per_primitive = true;
			else
				need_per_vertex = true;
		}
	});

	// If we have per-primitive outputs, and no per-primitive builtins,
	// empty version of gl_MeshPerPrimitiveEXT will be emitted.
	// If we don't use block IO for vertex output, we'll also need to synthesize the PerVertex block.

	const auto generate_block = [&](const char *block_name, const char *instance_name, bool per_primitive) -> uint32_t {
		auto &execution = get_entry_point();

		uint32_t op_type = ir.increase_bound_by(4);
		uint32_t op_arr = op_type + 1;
		uint32_t op_ptr = op_type + 2;
		uint32_t op_var = op_type + 3;

		auto &type = set<SPIRType>(op_type);
		type.basetype = SPIRType::Struct;
		set_name(op_type, block_name);
		set_decoration(op_type, DecorationBlock);
		if (per_primitive)
			set_decoration(op_type, DecorationPerPrimitiveEXT);

		auto &arr = set<SPIRType>(op_arr, type);
		arr.parent_type = type.self;
		arr.array.push_back(per_primitive ? execution.output_primitives : execution.output_vertices);
		arr.array_size_literal.push_back(true);

		auto &ptr = set<SPIRType>(op_ptr, arr);
		ptr.parent_type = arr.self;
		ptr.pointer = true;
		ptr.pointer_depth++;
		ptr.storage = StorageClassOutput;
		set_decoration(op_ptr, DecorationBlock);
		set_name(op_ptr, block_name);

		auto &var = set<SPIRVariable>(op_var, op_ptr, StorageClassOutput);
		if (per_primitive)
			set_decoration(op_var, DecorationPerPrimitiveEXT);
		set_name(op_var, instance_name);
		execution.interface_variables.push_back(var.self);

		return op_var;
	};

	if (id_per_vertex == 0 && need_per_vertex)
		id_per_vertex = generate_block("gl_MeshPerVertexEXT", "gl_MeshVerticesEXT", false);
	if (id_per_primitive == 0 && need_per_primitive)
		id_per_primitive = generate_block("gl_MeshPerPrimitiveEXT", "gl_MeshPrimitivesEXT", true);

	unordered_set<uint32_t> processed_func_ids;
	analyze_meshlet_writes(ir.default_entry_point, id_per_vertex, id_per_primitive, processed_func_ids);
}

void CompilerHLSL::analyze_meshlet_writes(uint32_t func_id, uint32_t id_per_vertex, uint32_t id_per_primitive,
                                          std::unordered_set<uint32_t> &processed_func_ids)
{
	// Avoid processing a function more than once
	if (processed_func_ids.find(func_id) != processed_func_ids.end())
		return;
	processed_func_ids.insert(func_id);

	auto &func = get<SPIRFunction>(func_id);
	// Recursively establish global args added to functions on which we depend.
	for (auto& block : func.blocks)
	{
		auto &b = get<SPIRBlock>(block);
		for (auto &i : b.ops)
		{
			auto ops = stream(i);
			auto op = static_cast<Op>(i.op);

			switch (op)
			{
			case OpFunctionCall:
			{
				// Then recurse into the function itself to extract globals used internally in the function
				uint32_t inner_func_id = ops[2];
				analyze_meshlet_writes(inner_func_id, id_per_vertex, id_per_primitive, processed_func_ids);
				auto &inner_func = get<SPIRFunction>(inner_func_id);
				for (auto &iarg : inner_func.arguments)
				{
					if (!iarg.alias_global_variable)
						continue;

					bool already_declared = false;
					for (auto &arg : func.arguments)
					{
						if (arg.id == iarg.id)
						{
							already_declared = true;
							break;
						}
					}

					if (!already_declared)
					{
						// basetype is effectively ignored here since we declare the argument
						// with explicit types. Just pass down a valid type.
						func.arguments.push_back({ expression_type_id(iarg.id), iarg.id,
						                           iarg.read_count, iarg.write_count, true });
					}
				}
				break;
			}

			case OpStore:
			case OpLoad:
			case OpInBoundsAccessChain:
			case OpAccessChain:
			case OpPtrAccessChain:
			case OpInBoundsPtrAccessChain:
			case OpArrayLength:
			{
				auto *var = maybe_get<SPIRVariable>(ops[op == OpStore ? 0 : 2]);
				if (var && (var->storage == StorageClassOutput || var->storage == StorageClassTaskPayloadWorkgroupEXT))
				{
					bool already_declared = false;
					auto builtin_type = BuiltIn(get_decoration(var->self, DecorationBuiltIn));

					uint32_t var_id = var->self;
					if (var->storage != StorageClassTaskPayloadWorkgroupEXT &&
						builtin_type != BuiltInPrimitivePointIndicesEXT &&
						builtin_type != BuiltInPrimitiveLineIndicesEXT &&
						builtin_type != BuiltInPrimitiveTriangleIndicesEXT)
					{
						var_id = is_per_primitive_variable(*var) ? id_per_primitive : id_per_vertex;
					}

					for (auto &arg : func.arguments)
					{
						if (arg.id == var_id)
						{
							already_declared = true;
							break;
						}
					}

					if (!already_declared)
					{
						// basetype is effectively ignored here since we declare the argument
						// with explicit types. Just pass down a valid type.
						uint32_t type_id = expression_type_id(var_id);
						if (var->storage == StorageClassTaskPayloadWorkgroupEXT)
							func.arguments.push_back({ type_id, var_id, 1u, 0u, true });
						else
							func.arguments.push_back({ type_id, var_id, 1u, 1u, true });
					}
				}
				break;
			}

			default:
				break;
			}
		}
	}
}

void CompilerHLSL::emit_rayquery_function(const char *commited, const char *candidate, const uint32_t *ops)
{
	flush_variable_declaration(ops[0]);
	uint32_t is_commited = evaluate_constant_u32(ops[3]);
	emit_op(ops[0], ops[1], join(to_expression(ops[2]), is_commited ? commited : candidate), false);
}

void CompilerHLSL::emit_mesh_tasks(SPIRBlock &block)
{
	if (block.mesh.payload != 0)
	{
		statement("DispatchMesh(", to_unpacked_expression(block.mesh.groups[0]), ", ", to_unpacked_expression(block.mesh.groups[1]), ", ",
		    to_unpacked_expression(block.mesh.groups[2]), ", ", to_unpacked_expression(block.mesh.payload), ");");
	}
	else
	{
		SPIRV_CROSS_THROW("Amplification shader in HLSL must have payload");
	}
}

void CompilerHLSL::emit_push_constant_block(const SPIRVariable &var)
{
	if (flattened_buffer_blocks.count(var.self))
	{
		emit_buffer_block_flattened(var);
	}
	else if (root_constants_layout.empty())
	{
		emit_buffer_block(var);
	}
	else
	{
		for (const auto &layout : root_constants_layout)
		{
			auto &type = get<SPIRType>(var.basetype);

			uint32_t failed_index = 0;
			if (buffer_is_packing_standard(type, BufferPackingHLSLCbufferPackOffset, &failed_index, layout.start,
			                               layout.end))
				set_extended_decoration(type.self, SPIRVCrossDecorationExplicitOffset);
			else
			{
				SPIRV_CROSS_THROW(join("Root constant cbuffer ID ", var.self, " (name: ", to_name(type.self), ")",
				                       ", member index ", failed_index, " (name: ", to_member_name(type, failed_index),
				                       ") cannot be expressed with either HLSL packing layout or packoffset."));
			}

			flattened_structs[var.self] = false;
			type.member_name_cache.clear();
			add_resource_name(var.self);
			auto &memb = ir.meta[type.self].members;

			statement("cbuffer SPIRV_CROSS_RootConstant_", to_name(var.self),
			          to_resource_register(HLSL_BINDING_AUTO_PUSH_CONSTANT_BIT, 'b', layout.binding, layout.space));
			begin_scope();

			// Index of the next field in the generated root constant constant buffer
			auto constant_index = 0u;

			// Iterate over all member of the push constant and check which of the fields
			// fit into the given root constant layout.
			for (auto i = 0u; i < memb.size(); i++)
			{
				const auto offset = memb[i].offset;
				if (layout.start <= offset && offset < layout.end)
				{
					const auto &member = type.member_types[i];

					add_member_name(type, constant_index);
					auto backup_name = get_member_name(type.self, i);
					auto member_name = to_member_name(type, i);
					member_name = join(to_name(var.self), "_", member_name);
					ParsedIR::sanitize_underscores(member_name);
					set_member_name(type.self, constant_index, member_name);
					emit_struct_member(type, member, i, "", layout.start);
					set_member_name(type.self, constant_index, backup_name);

					constant_index++;
				}
			}

			end_scope_decl();
		}
	}
}

void CompilerHLSL::emit_legacy_uniform(const SPIRVariable &var)
{
	auto &type = get<SPIRType>(var.basetype);
	switch (type.basetype)
	{
	case SPIRType::Sampler:
	case SPIRType::Image:
		SPIRV_CROSS_THROW("Separate image and samplers not supported in legacy HLSL.");

	default:
		statement(variable_decl(var), ";");
		break;
	}
}

string CompilerHLSL::bitcast_glsl_op(const SPIRType &out_type, const SPIRType &in_type)
{
	if (out_type.basetype == SPIRType::UInt && in_type.basetype == SPIRType::Int)
		return type_to_glsl(out_type);
	else if (out_type.basetype == SPIRType::UInt64 && in_type.basetype == SPIRType::Int64)
		return type_to_glsl(out_type);
	else if (out_type.basetype == SPIRType::UInt && in_type.basetype == SPIRType::Float)
		return "asuint";
	else if (out_type.basetype == SPIRType::Int && in_type.basetype == SPIRType::UInt)
		return type_to_glsl(out_type);
	else if (out_type.basetype == SPIRType::Int64 && in_type.basetype == SPIRType::UInt64)
		return type_to_glsl(out_type);
	else if (out_type.basetype == SPIRType::Int && in_type.basetype == SPIRType::Float)
		return "asint";
	else if (out_type.basetype == SPIRType::Float && in_type.basetype == SPIRType::UInt)
		return "asfloat";
	else if (out_type.basetype == SPIRType::Float && in_type.basetype == SPIRType::Int)
		return "asfloat";
	else if (out_type.basetype == SPIRType::Int64 && in_type.basetype == SPIRType::Double)
		SPIRV_CROSS_THROW("Double to Int64 is not supported in HLSL.");
	else if (out_type.basetype == SPIRType::UInt64 && in_type.basetype == SPIRType::Double)
		SPIRV_CROSS_THROW("Double to UInt64 is not supported in HLSL.");
	else if (out_type.basetype == SPIRType::Double && in_type.basetype == SPIRType::Int64)
		return "asdouble";
	else if (out_type.basetype == SPIRType::Double && in_type.basetype == SPIRType::UInt64)
		return "asdouble";
	else if (out_type.basetype == SPIRType::Half && in_type.basetype == SPIRType::UInt && in_type.vecsize == 1)
	{
		if (!requires_explicit_fp16_packing)
		{
			requires_explicit_fp16_packing = true;
			force_recompile();
		}
		return "spvUnpackFloat2x16";
	}
	else if (out_type.basetype == SPIRType::UInt && in_type.basetype == SPIRType::Half && in_type.vecsize == 2)
	{
		if (!requires_explicit_fp16_packing)
		{
			requires_explicit_fp16_packing = true;
			force_recompile();
		}
		return "spvPackFloat2x16";
	}
	else if (out_type.basetype == SPIRType::UShort && in_type.basetype == SPIRType::Half)
	{
		if (hlsl_options.shader_model < 40)
			SPIRV_CROSS_THROW("Half to UShort requires Shader Model 4.");
		return "(" + type_to_glsl(out_type) + ")f32tof16";
	}
	else if (out_type.basetype == SPIRType::Half && in_type.basetype == SPIRType::UShort)
	{
		if (hlsl_options.shader_model < 40)
			SPIRV_CROSS_THROW("UShort to Half requires Shader Model 4.");
		return "(" + type_to_glsl(out_type) + ")f16tof32";
	}
	else
		return "";
}

void CompilerHLSL::read_access_chain_array(const string &lhs, const SPIRAccessChain &chain)
{
	auto &type = get<SPIRType>(chain.basetype);

	// Need to use a reserved identifier here since it might shadow an identifier in the access chain input or other loops.
	auto ident = get_unique_identifier();

	statement("[unroll]");
	statement("for (int ", ident, " = 0; ", ident, " < ", to_array_size(type, uint32_t(type.array.size() - 1)), "; ",
	          ident, "++)");
	begin_scope();
	auto subchain = chain;
	subchain.dynamic_index = join(ident, " * ", chain.array_stride, " + ", chain.dynamic_index);
	subchain.basetype = type.parent_type;
	if (!get<SPIRType>(subchain.basetype).array.empty())
		subchain.array_stride = get_decoration(subchain.basetype, DecorationArrayStride);
	read_access_chain(nullptr, join(lhs, "[", ident, "]"), subchain);
	end_scope();
}

void CompilerHLSL::read_access_chain_struct(const string &lhs, const SPIRAccessChain &chain)
{
	auto &type = get<SPIRType>(chain.basetype);
	auto subchain = chain;
	uint32_t member_count = uint32_t(type.member_types.size());

	for (uint32_t i = 0; i < member_count; i++)
	{
		uint32_t offset = type_struct_member_offset(type, i);
		subchain.static_index = chain.static_index + offset;
		subchain.basetype = type.member_types[i];

		subchain.matrix_stride = 0;
		subchain.array_stride = 0;
		subchain.row_major_matrix = false;

		auto &member_type = get<SPIRType>(subchain.basetype);
		if (member_type.columns > 1)
		{
			subchain.matrix_stride = type_struct_member_matrix_stride(type, i);
			subchain.row_major_matrix = has_member_decoration(type.self, i, DecorationRowMajor);
		}

		if (!member_type.array.empty())
			subchain.array_stride = type_struct_member_array_stride(type, i);

		read_access_chain(nullptr, join(lhs, ".", to_member_name(type, i)), subchain);
	}
}

void CompilerHLSL::read_access_chain(string *expr, const string &lhs, const SPIRAccessChain &chain)
{
	auto &type = get<SPIRType>(chain.basetype);

	SPIRType target_type;
	target_type.basetype = SPIRType::UInt;
	target_type.vecsize = type.vecsize;
	target_type.columns = type.columns;

	if (!type.array.empty())
	{
		read_access_chain_array(lhs, chain);
		return;
	}
	else if (type.basetype == SPIRType::Struct)
	{
		read_access_chain_struct(lhs, chain);
		return;
	}
	else if (type.width != 32 && !hlsl_options.enable_16bit_types)
		SPIRV_CROSS_THROW("Reading types other than 32-bit from ByteAddressBuffer not yet supported, unless SM 6.2 and "
		                  "native 16-bit types are enabled.");

	string base = chain.base;
	if (has_decoration(chain.self, DecorationNonUniform))
		convert_non_uniform_expression(base, chain.self);

	bool templated_load = hlsl_options.shader_model >= 62;
	string load_expr;

	string template_expr;
	if (templated_load)
		template_expr = join("<", type_to_glsl(type), ">");

	// Load a vector or scalar.
	if (type.columns == 1 && !chain.row_major_matrix)
	{
		const char *load_op = nullptr;
		switch (type.vecsize)
		{
		case 1:
			load_op = "Load";
			break;
		case 2:
			load_op = "Load2";
			break;
		case 3:
			load_op = "Load3";
			break;
		case 4:
			load_op = "Load4";
			break;
		default:
			SPIRV_CROSS_THROW("Unknown vector size.");
		}

		if (templated_load)
			load_op = "Load";

		load_expr = join(base, ".", load_op, template_expr, "(", chain.dynamic_index, chain.static_index, ")");
	}
	else if (type.columns == 1)
	{
		// Strided load since we are loading a column from a row-major matrix.
		if (templated_load)
		{
			auto scalar_type = type;
			scalar_type.vecsize = 1;
			scalar_type.columns = 1;
			template_expr = join("<", type_to_glsl(scalar_type), ">");
			if (type.vecsize > 1)
				load_expr += type_to_glsl(type) + "(";
		}
		else if (type.vecsize > 1)
		{
			load_expr = type_to_glsl(target_type);
			load_expr += "(";
		}

		for (uint32_t r = 0; r < type.vecsize; r++)
		{
			load_expr += join(base, ".Load", template_expr, "(", chain.dynamic_index,
			                  chain.static_index + r * chain.matrix_stride, ")");
			if (r + 1 < type.vecsize)
				load_expr += ", ";
		}

		if (type.vecsize > 1)
			load_expr += ")";
	}
	else if (!chain.row_major_matrix)
	{
		// Load a matrix, column-major, the easy case.
		const char *load_op = nullptr;
		switch (type.vecsize)
		{
		case 1:
			load_op = "Load";
			break;
		case 2:
			load_op = "Load2";
			break;
		case 3:
			load_op = "Load3";
			break;
		case 4:
			load_op = "Load4";
			break;
		default:
			SPIRV_CROSS_THROW("Unknown vector size.");
		}

		if (templated_load)
		{
			auto vector_type = type;
			vector_type.columns = 1;
			template_expr = join("<", type_to_glsl(vector_type), ">");
			load_expr = type_to_glsl(type);
			load_op = "Load";
		}
		else
		{
			// Note, this loading style in HLSL is *actually* row-major, but we always treat matrices as transposed in this backend,
			// so row-major is technically column-major ...
			load_expr = type_to_glsl(target_type);
		}
		load_expr += "(";

		for (uint32_t c = 0; c < type.columns; c++)
		{
			load_expr += join(base, ".", load_op, template_expr, "(", chain.dynamic_index,
			                  chain.static_index + c * chain.matrix_stride, ")");
			if (c + 1 < type.columns)
				load_expr += ", ";
		}
		load_expr += ")";
	}
	else
	{
		// Pick out elements one by one ... Hopefully compilers are smart enough to recognize this pattern
		// considering HLSL is "row-major decl", but "column-major" memory layout (basically implicit transpose model, ugh) ...

		if (templated_load)
		{
			load_expr = type_to_glsl(type);
			auto scalar_type = type;
			scalar_type.vecsize = 1;
			scalar_type.columns = 1;
			template_expr = join("<", type_to_glsl(scalar_type), ">");
		}
		else
			load_expr = type_to_glsl(target_type);

		load_expr += "(";

		for (uint32_t c = 0; c < type.columns; c++)
		{
			for (uint32_t r = 0; r < type.vecsize; r++)
			{
				load_expr += join(base, ".Load", template_expr, "(", chain.dynamic_index,
				                  chain.static_index + c * (type.width / 8) + r * chain.matrix_stride, ")");

				if ((r + 1 < type.vecsize) || (c + 1 < type.columns))
					load_expr += ", ";
			}
		}
		load_expr += ")";
	}

	if (!templated_load)
	{
		auto bitcast_op = bitcast_glsl_op(type, target_type);
		if (!bitcast_op.empty())
			load_expr = join(bitcast_op, "(", load_expr, ")");
	}

	if (lhs.empty())
	{
		assert(expr);
		*expr = std::move(load_expr);
	}
	else
		statement(lhs, " = ", load_expr, ";");
}

void CompilerHLSL::write_access_chain_array(const SPIRAccessChain &chain, uint32_t value,
                                            const SmallVector<uint32_t> &composite_chain)
{
	auto &type = get<SPIRType>(chain.basetype);

	// Need to use a reserved identifier here since it might shadow an identifier in the access chain input or other loops.
	auto ident = get_unique_identifier();

	uint32_t id = ir.increase_bound_by(2);
	uint32_t int_type_id = id + 1;
	SPIRType int_type;
	int_type.basetype = SPIRType::Int;
	int_type.width = 32;
	set<SPIRType>(int_type_id, int_type);
	set<SPIRExpression>(id, ident, int_type_id, true);
	set_name(id, ident);
	suppressed_usage_tracking.insert(id);

	statement("[unroll]");
	statement("for (int ", ident, " = 0; ", ident, " < ", to_array_size(type, uint32_t(type.array.size() - 1)), "; ",
	          ident, "++)");
	begin_scope();
	auto subchain = chain;
	subchain.dynamic_index = join(ident, " * ", chain.array_stride, " + ", chain.dynamic_index);
	subchain.basetype = type.parent_type;

	// Forcefully allow us to use an ID here by setting MSB.
	auto subcomposite_chain = composite_chain;
	subcomposite_chain.push_back(0x80000000u | id);

	if (!get<SPIRType>(subchain.basetype).array.empty())
		subchain.array_stride = get_decoration(subchain.basetype, DecorationArrayStride);

	write_access_chain(subchain, value, subcomposite_chain);
	end_scope();
}

void CompilerHLSL::write_access_chain_struct(const SPIRAccessChain &chain, uint32_t value,
                                             const SmallVector<uint32_t> &composite_chain)
{
	auto &type = get<SPIRType>(chain.basetype);
	uint32_t member_count = uint32_t(type.member_types.size());
	auto subchain = chain;

	auto subcomposite_chain = composite_chain;
	subcomposite_chain.push_back(0);

	for (uint32_t i = 0; i < member_count; i++)
	{
		uint32_t offset = type_struct_member_offset(type, i);
		subchain.static_index = chain.static_index + offset;
		subchain.basetype = type.member_types[i];

		subchain.matrix_stride = 0;
		subchain.array_stride = 0;
		subchain.row_major_matrix = false;

		auto &member_type = get<SPIRType>(subchain.basetype);
		if (member_type.columns > 1)
		{
			subchain.matrix_stride = type_struct_member_matrix_stride(type, i);
			subchain.row_major_matrix = has_member_decoration(type.self, i, DecorationRowMajor);
		}

		if (!member_type.array.empty())
			subchain.array_stride = type_struct_member_array_stride(type, i);

		subcomposite_chain.back() = i;
		write_access_chain(subchain, value, subcomposite_chain);
	}
}

string CompilerHLSL::write_access_chain_value(uint32_t value, const SmallVector<uint32_t> &composite_chain,
                                              bool enclose)
{
	string ret;
	if (composite_chain.empty())
		ret = to_expression(value);
	else
	{
		AccessChainMeta meta;
		ret = access_chain_internal(value, composite_chain.data(), uint32_t(composite_chain.size()),
		                            ACCESS_CHAIN_INDEX_IS_LITERAL_BIT | ACCESS_CHAIN_LITERAL_MSB_FORCE_ID, &meta);
	}

	if (enclose)
		ret = enclose_expression(ret);
	return ret;
}

void CompilerHLSL::write_access_chain(const SPIRAccessChain &chain, uint32_t value,
                                      const SmallVector<uint32_t> &composite_chain)
{
	auto &type = get<SPIRType>(chain.basetype);

	// Make sure we trigger a read of the constituents in the access chain.
	track_expression_read(chain.self);

	SPIRType target_type;
	target_type.basetype = SPIRType::UInt;
	target_type.vecsize = type.vecsize;
	target_type.columns = type.columns;

	if (!type.array.empty())
	{
		write_access_chain_array(chain, value, composite_chain);
		register_write(chain.self);
		return;
	}
	else if (type.basetype == SPIRType::Struct)
	{
		write_access_chain_struct(chain, value, composite_chain);
		register_write(chain.self);
		return;
	}
	else if (type.width != 32 && !hlsl_options.enable_16bit_types)
		SPIRV_CROSS_THROW("Writing types other than 32-bit to RWByteAddressBuffer not yet supported, unless SM 6.2 and "
		                  "native 16-bit types are enabled.");

	bool templated_store = hlsl_options.shader_model >= 62;

	auto base = chain.base;
	if (has_decoration(chain.self, DecorationNonUniform))
		convert_non_uniform_expression(base, chain.self);

	string template_expr;
	if (templated_store)
		template_expr = join("<", type_to_glsl(type), ">");

	if (type.columns == 1 && !chain.row_major_matrix)
	{
		const char *store_op = nullptr;
		switch (type.vecsize)
		{
		case 1:
			store_op = "Store";
			break;
		case 2:
			store_op = "Store2";
			break;
		case 3:
			store_op = "Store3";
			break;
		case 4:
			store_op = "Store4";
			break;
		default:
			SPIRV_CROSS_THROW("Unknown vector size.");
		}

		auto store_expr = write_access_chain_value(value, composite_chain, false);

		if (!templated_store)
		{
			auto bitcast_op = bitcast_glsl_op(target_type, type);
			if (!bitcast_op.empty())
				store_expr = join(bitcast_op, "(", store_expr, ")");
		}
		else
			store_op = "Store";
		statement(base, ".", store_op, template_expr, "(", chain.dynamic_index, chain.static_index, ", ",
		          store_expr, ");");
	}
	else if (type.columns == 1)
	{
		if (templated_store)
		{
			auto scalar_type = type;
			scalar_type.vecsize = 1;
			scalar_type.columns = 1;
			template_expr = join("<", type_to_glsl(scalar_type), ">");
		}

		// Strided store.
		for (uint32_t r = 0; r < type.vecsize; r++)
		{
			auto store_expr = write_access_chain_value(value, composite_chain, true);
			if (type.vecsize > 1)
			{
				store_expr += ".";
				store_expr += index_to_swizzle(r);
			}
			remove_duplicate_swizzle(store_expr);

			if (!templated_store)
			{
				auto bitcast_op = bitcast_glsl_op(target_type, type);
				if (!bitcast_op.empty())
					store_expr = join(bitcast_op, "(", store_expr, ")");
			}

			statement(base, ".Store", template_expr, "(", chain.dynamic_index,
			          chain.static_index + chain.matrix_stride * r, ", ", store_expr, ");");
		}
	}
	else if (!chain.row_major_matrix)
	{
		const char *store_op = nullptr;
		switch (type.vecsize)
		{
		case 1:
			store_op = "Store";
			break;
		case 2:
			store_op = "Store2";
			break;
		case 3:
			store_op = "Store3";
			break;
		case 4:
			store_op = "Store4";
			break;
		default:
			SPIRV_CROSS_THROW("Unknown vector size.");
		}

		if (templated_store)
		{
			store_op = "Store";
			auto vector_type = type;
			vector_type.columns = 1;
			template_expr = join("<", type_to_glsl(vector_type), ">");
		}

		for (uint32_t c = 0; c < type.columns; c++)
		{
			auto store_expr = join(write_access_chain_value(value, composite_chain, true), "[", c, "]");

			if (!templated_store)
			{
				auto bitcast_op = bitcast_glsl_op(target_type, type);
				if (!bitcast_op.empty())
					store_expr = join(bitcast_op, "(", store_expr, ")");
			}

			statement(base, ".", store_op, template_expr, "(", chain.dynamic_index,
			          chain.static_index + c * chain.matrix_stride, ", ", store_expr, ");");
		}
	}
	else
	{
		if (templated_store)
		{
			auto scalar_type = type;
			scalar_type.vecsize = 1;
			scalar_type.columns = 1;
			template_expr = join("<", type_to_glsl(scalar_type), ">");
		}

		for (uint32_t r = 0; r < type.vecsize; r++)
		{
			for (uint32_t c = 0; c < type.columns; c++)
			{
				auto store_expr =
				    join(write_access_chain_value(value, composite_chain, true), "[", c, "].", index_to_swizzle(r));
				remove_duplicate_swizzle(store_expr);
				auto bitcast_op = bitcast_glsl_op(target_type, type);
				if (!bitcast_op.empty())
					store_expr = join(bitcast_op, "(", store_expr, ")");
				statement(base, ".Store", template_expr, "(", chain.dynamic_index,
				          chain.static_index + c * (type.width / 8) + r * chain.matrix_stride, ", ", store_expr, ");");
			}
		}
	}

	register_write(chain.self);
}

void CompilerHLSL::emit_atomic(const uint32_t *ops, uint32_t length, spv::Op op)
{
	const char *atomic_op = nullptr;

	string value_expr;
	if (op != OpAtomicIDecrement && op != OpAtomicIIncrement && op != OpAtomicLoad && op != OpAtomicStore)
		value_expr = to_expression(ops[op == OpAtomicCompareExchange ? 6 : 5]);

	bool is_atomic_store = false;

	switch (op)
	{
	case OpAtomicIIncrement:
		atomic_op = "InterlockedAdd";
		value_expr = "1";
		break;

	case OpAtomicIDecrement:
		atomic_op = "InterlockedAdd";
		value_expr = "-1";
		break;

	case OpAtomicLoad:
		atomic_op = "InterlockedAdd";
		value_expr = "0";
		break;

	case OpAtomicISub:
		atomic_op = "InterlockedAdd";
		value_expr = join("-", enclose_expression(value_expr));
		break;

	case OpAtomicSMin:
	case OpAtomicUMin:
		atomic_op = "InterlockedMin";
		break;

	case OpAtomicSMax:
	case OpAtomicUMax:
		atomic_op = "InterlockedMax";
		break;

	case OpAtomicAnd:
		atomic_op = "InterlockedAnd";
		break;

	case OpAtomicOr:
		atomic_op = "InterlockedOr";
		break;

	case OpAtomicXor:
		atomic_op = "InterlockedXor";
		break;

	case OpAtomicIAdd:
		atomic_op = "InterlockedAdd";
		break;

	case OpAtomicExchange:
		atomic_op = "InterlockedExchange";
		break;

	case OpAtomicStore:
		atomic_op = "InterlockedExchange";
		is_atomic_store = true;
		break;

	case OpAtomicCompareExchange:
		if (length < 8)
			SPIRV_CROSS_THROW("Not enough data for opcode.");
		atomic_op = "InterlockedCompareExchange";
		value_expr = join(to_expression(ops[7]), ", ", value_expr);
		break;

	default:
		SPIRV_CROSS_THROW("Unknown atomic opcode.");
	}

	if (is_atomic_store)
	{
		auto &data_type = expression_type(ops[0]);
		auto *chain = maybe_get<SPIRAccessChain>(ops[0]);

		auto &tmp_id = extra_sub_expressions[ops[0]];
		if (!tmp_id)
		{
			tmp_id = ir.increase_bound_by(1);
			emit_uninitialized_temporary_expression(get_pointee_type(data_type).self, tmp_id);
		}

		if (data_type.storage == StorageClassImage || !chain)
		{
			statement(atomic_op, "(", to_non_uniform_aware_expression(ops[0]), ", ",
			          to_expression(ops[3]), ", ", to_expression(tmp_id), ");");
		}
		else
		{
			string base = chain->base;
			if (has_decoration(chain->self, DecorationNonUniform))
				convert_non_uniform_expression(base, chain->self);
			// RWByteAddress buffer is always uint in its underlying type.
			statement(base, ".", atomic_op, "(", chain->dynamic_index, chain->static_index, ", ",
			          to_expression(ops[3]), ", ", to_expression(tmp_id), ");");
		}
	}
	else
	{
		uint32_t result_type = ops[0];
		uint32_t id = ops[1];
		forced_temporaries.insert(ops[1]);

		auto &type = get<SPIRType>(result_type);
		statement(variable_decl(type, to_name(id)), ";");

		auto &data_type = expression_type(ops[2]);
		auto *chain = maybe_get<SPIRAccessChain>(ops[2]);
		SPIRType::BaseType expr_type;
		if (data_type.storage == StorageClassImage || !chain)
		{
			statement(atomic_op, "(", to_non_uniform_aware_expression(ops[2]), ", ", value_expr, ", ", to_name(id), ");");
			expr_type = data_type.basetype;
		}
		else
		{
			// RWByteAddress buffer is always uint in its underlying type.
			string base = chain->base;
			if (has_decoration(chain->self, DecorationNonUniform))
				convert_non_uniform_expression(base, chain->self);
			expr_type = SPIRType::UInt;
			statement(base, ".", atomic_op, "(", chain->dynamic_index, chain->static_index, ", ", value_expr,
			          ", ", to_name(id), ");");
		}

		auto expr = bitcast_expression(type, expr_type, to_name(id));
		set<SPIRExpression>(id, expr, result_type, true);
	}
	flush_all_atomic_capable_variables();
}

void CompilerHLSL::emit_subgroup_op(const Instruction &i)
{
	if (hlsl_options.shader_model < 60)
		SPIRV_CROSS_THROW("Wave ops requires SM 6.0 or higher.");

	const uint32_t *ops = stream(i);
	auto op = static_cast<Op>(i.op);

	uint32_t result_type = ops[0];
	uint32_t id = ops[1];

	auto scope = static_cast<Scope>(evaluate_constant_u32(ops[2]));
	if (scope != ScopeSubgroup)
		SPIRV_CROSS_THROW("Only subgroup scope is supported.");

	const auto make_inclusive_Sum = [&](const string &expr) -> string {
		return join(expr, " + ", to_expression(ops[4]));
	};

	const auto make_inclusive_Product = [&](const string &expr) -> string {
		return join(expr, " * ", to_expression(ops[4]));
	};

	// If we need to do implicit bitcasts, make sure we do it with the correct type.
	uint32_t integer_width = get_integer_width_for_instruction(i);
	auto int_type = to_signed_basetype(integer_width);
	auto uint_type = to_unsigned_basetype(integer_width);

#define make_inclusive_BitAnd(expr) ""
#define make_inclusive_BitOr(expr) ""
#define make_inclusive_BitXor(expr) ""
#define make_inclusive_Min(expr) ""
#define make_inclusive_Max(expr) ""

	switch (op)
	{
	case OpGroupNonUniformElect:
		emit_op(result_type, id, "WaveIsFirstLane()", true);
		break;

	case OpGroupNonUniformBroadcast:
		emit_binary_func_op(result_type, id, ops[3], ops[4], "WaveReadLaneAt");
		break;

	case OpGroupNonUniformBroadcastFirst:
		emit_unary_func_op(result_type, id, ops[3], "WaveReadLaneFirst");
		break;

	case OpGroupNonUniformBallot:
		emit_unary_func_op(result_type, id, ops[3], "WaveActiveBallot");
		break;

	case OpGroupNonUniformInverseBallot:
		SPIRV_CROSS_THROW("Cannot trivially implement InverseBallot in HLSL.");

	case OpGroupNonUniformBallotBitExtract:
		SPIRV_CROSS_THROW("Cannot trivially implement BallotBitExtract in HLSL.");

	case OpGroupNonUniformBallotFindLSB:
		SPIRV_CROSS_THROW("Cannot trivially implement BallotFindLSB in HLSL.");

	case OpGroupNonUniformBallotFindMSB:
		SPIRV_CROSS_THROW("Cannot trivially implement BallotFindMSB in HLSL.");

	case OpGroupNonUniformBallotBitCount:
	{
		auto operation = static_cast<GroupOperation>(ops[3]);
		bool forward = should_forward(ops[4]);
		if (operation == GroupOperationReduce)
		{
			auto left = join("countbits(", to_enclosed_expression(ops[4]), ".x) + countbits(",
			                 to_enclosed_expression(ops[4]), ".y)");
			auto right = join("countbits(", to_enclosed_expression(ops[4]), ".z) + countbits(",
			                  to_enclosed_expression(ops[4]), ".w)");
			emit_op(result_type, id, join(left, " + ", right), forward);
			inherit_expression_dependencies(id, ops[4]);
		}
		else if (operation == GroupOperationInclusiveScan)
		{
			auto left = join("countbits(", to_enclosed_expression(ops[4]), ".x & gl_SubgroupLeMask.x) + countbits(",
			                 to_enclosed_expression(ops[4]), ".y & gl_SubgroupLeMask.y)");
			auto right = join("countbits(", to_enclosed_expression(ops[4]), ".z & gl_SubgroupLeMask.z) + countbits(",
			                  to_enclosed_expression(ops[4]), ".w & gl_SubgroupLeMask.w)");
			emit_op(result_type, id, join(left, " + ", right), forward);
			if (!active_input_builtins.get(BuiltInSubgroupLeMask))
			{
				active_input_builtins.set(BuiltInSubgroupLeMask);
				force_recompile_guarantee_forward_progress();
			}
		}
		else if (operation == GroupOperationExclusiveScan)
		{
			auto left = join("countbits(", to_enclosed_expression(ops[4]), ".x & gl_SubgroupLtMask.x) + countbits(",
			                 to_enclosed_expression(ops[4]), ".y & gl_SubgroupLtMask.y)");
			auto right = join("countbits(", to_enclosed_expression(ops[4]), ".z & gl_SubgroupLtMask.z) + countbits(",
			                  to_enclosed_expression(ops[4]), ".w & gl_SubgroupLtMask.w)");
			emit_op(result_type, id, join(left, " + ", right), forward);
			if (!active_input_builtins.get(BuiltInSubgroupLtMask))
			{
				active_input_builtins.set(BuiltInSubgroupLtMask);
				force_recompile_guarantee_forward_progress();
			}
		}
		else
			SPIRV_CROSS_THROW("Invalid BitCount operation.");
		break;
	}

	case OpGroupNonUniformShuffle:
		emit_binary_func_op(result_type, id, ops[3], ops[4], "WaveReadLaneAt");
		break;
	case OpGroupNonUniformShuffleXor:
	{
		bool forward = should_forward(ops[3]);
		emit_op(ops[0], ops[1],
		        join("WaveReadLaneAt(", to_unpacked_expression(ops[3]), ", ",
		             "WaveGetLaneIndex() ^ ", to_enclosed_expression(ops[4]), ")"), forward);
		inherit_expression_dependencies(ops[1], ops[3]);
		break;
	}
	case OpGroupNonUniformShuffleUp:
	{
		bool forward = should_forward(ops[3]);
		emit_op(ops[0], ops[1],
		        join("WaveReadLaneAt(", to_unpacked_expression(ops[3]), ", ",
		             "WaveGetLaneIndex() - ", to_enclosed_expression(ops[4]), ")"), forward);
		inherit_expression_dependencies(ops[1], ops[3]);
		break;
	}
	case OpGroupNonUniformShuffleDown:
	{
		bool forward = should_forward(ops[3]);
		emit_op(ops[0], ops[1],
		        join("WaveReadLaneAt(", to_unpacked_expression(ops[3]), ", ",
		             "WaveGetLaneIndex() + ", to_enclosed_expression(ops[4]), ")"), forward);
		inherit_expression_dependencies(ops[1], ops[3]);
		break;
	}

	case OpGroupNonUniformAll:
		emit_unary_func_op(result_type, id, ops[3], "WaveActiveAllTrue");
		break;

	case OpGroupNonUniformAny:
		emit_unary_func_op(result_type, id, ops[3], "WaveActiveAnyTrue");
		break;

	case OpGroupNonUniformAllEqual:
		emit_unary_func_op(result_type, id, ops[3], "WaveActiveAllEqual");
		break;

	// clang-format off
#define HLSL_GROUP_OP(op, hlsl_op, supports_scan) \
case OpGroupNonUniform##op: \
	{ \
		auto operation = static_cast<GroupOperation>(ops[3]); \
		if (operation == GroupOperationReduce) \
			emit_unary_func_op(result_type, id, ops[4], "WaveActive" #hlsl_op); \
		else if (operation == GroupOperationInclusiveScan && supports_scan) \
        { \
			bool forward = should_forward(ops[4]); \
			emit_op(result_type, id, make_inclusive_##hlsl_op (join("WavePrefix" #hlsl_op, "(", to_expression(ops[4]), ")")), forward); \
			inherit_expression_dependencies(id, ops[4]); \
        } \
		else if (operation == GroupOperationExclusiveScan && supports_scan) \
			emit_unary_func_op(result_type, id, ops[4], "WavePrefix" #hlsl_op); \
		else if (operation == GroupOperationClusteredReduce) \
			SPIRV_CROSS_THROW("Cannot trivially implement ClusteredReduce in HLSL."); \
		else \
			SPIRV_CROSS_THROW("Invalid group operation."); \
		break; \
	}

#define HLSL_GROUP_OP_CAST(op, hlsl_op, type) \
case OpGroupNonUniform##op: \
	{ \
		auto operation = static_cast<GroupOperation>(ops[3]); \
		if (operation == GroupOperationReduce) \
			emit_unary_func_op_cast(result_type, id, ops[4], "WaveActive" #hlsl_op, type, type); \
		else \
			SPIRV_CROSS_THROW("Invalid group operation."); \
		break; \
	}

	HLSL_GROUP_OP(FAdd, Sum, true)
	HLSL_GROUP_OP(FMul, Product, true)
	HLSL_GROUP_OP(FMin, Min, false)
	HLSL_GROUP_OP(FMax, Max, false)
	HLSL_GROUP_OP(IAdd, Sum, true)
	HLSL_GROUP_OP(IMul, Product, true)
	HLSL_GROUP_OP_CAST(SMin, Min, int_type)
	HLSL_GROUP_OP_CAST(SMax, Max, int_type)
	HLSL_GROUP_OP_CAST(UMin, Min, uint_type)
	HLSL_GROUP_OP_CAST(UMax, Max, uint_type)
	HLSL_GROUP_OP(BitwiseAnd, BitAnd, false)
	HLSL_GROUP_OP(BitwiseOr, BitOr, false)
	HLSL_GROUP_OP(BitwiseXor, BitXor, false)
	HLSL_GROUP_OP_CAST(LogicalAnd, BitAnd, uint_type)
	HLSL_GROUP_OP_CAST(LogicalOr, BitOr, uint_type)
	HLSL_GROUP_OP_CAST(LogicalXor, BitXor, uint_type)

#undef HLSL_GROUP_OP
#undef HLSL_GROUP_OP_CAST
		// clang-format on

	case OpGroupNonUniformQuadSwap:
	{
		uint32_t direction = evaluate_constant_u32(ops[4]);
		if (direction == 0)
			emit_unary_func_op(result_type, id, ops[3], "QuadReadAcrossX");
		else if (direction == 1)
			emit_unary_func_op(result_type, id, ops[3], "QuadReadAcrossY");
		else if (direction == 2)
			emit_unary_func_op(result_type, id, ops[3], "QuadReadAcrossDiagonal");
		else
			SPIRV_CROSS_THROW("Invalid quad swap direction.");
		break;
	}

	case OpGroupNonUniformQuadBroadcast:
	{
		emit_binary_func_op(result_type, id, ops[3], ops[4], "QuadReadLaneAt");
		break;
	}

	default:
		SPIRV_CROSS_THROW("Invalid opcode for subgroup.");
	}

	register_control_dependent_expression(id);
}

void CompilerHLSL::require_texture_query_variant(uint32_t var_id)
{
	if (const auto *var = maybe_get_backing_variable(var_id))
		var_id = var->self;

	auto &type = expression_type(var_id);
	bool uav = type.image.sampled == 2;
	if (hlsl_options.nonwritable_uav_texture_as_srv && has_decoration(var_id, DecorationNonWritable))
		uav = false;

	uint32_t bit = 0;
	switch (type.image.dim)
	{
	case Dim1D:
		bit = type.image.arrayed ? Query1DArray : Query1D;
		break;

	case Dim2D:
		if (type.image.ms)
			bit = type.image.arrayed ? Query2DMSArray : Query2DMS;
		else
			bit = type.image.arrayed ? Query2DArray : Query2D;
		break;

	case Dim3D:
		bit = Query3D;
		break;

	case DimCube:
		bit = type.image.arrayed ? QueryCubeArray : QueryCube;
		break;

	case DimBuffer:
		bit = QueryBuffer;
		break;

	default:
		SPIRV_CROSS_THROW("Unsupported query type.");
	}

	switch (get<SPIRType>(type.image.type).basetype)
	{
	case SPIRType::Float:
		bit += QueryTypeFloat;
		break;

	case SPIRType::Int:
		bit += QueryTypeInt;
		break;

	case SPIRType::UInt:
		bit += QueryTypeUInt;
		break;

	default:
		SPIRV_CROSS_THROW("Unsupported query type.");
	}

	auto norm_state = image_format_to_normalized_state(type.image.format);
	auto &variant = uav ? required_texture_size_variants
	                          .uav[uint32_t(norm_state)][image_format_to_components(type.image.format) - 1] :
	                      required_texture_size_variants.srv;

	uint64_t mask = 1ull << bit;
	if ((variant & mask) == 0)
	{
		force_recompile();
		variant |= mask;
	}
}

VariableID CompilerHLSL::remap_num_workgroups_builtin()
{
	update_active_builtins();

	if (!active_input_builtins.get(BuiltInNumWorkgroups))
		return 0;

	// Create a new, fake UBO.
	uint32_t offset = ir.increase_bound_by(4);

	uint32_t uint_type_id = offset;
	uint32_t block_type_id = offset + 1;
	uint32_t block_pointer_type_id = offset + 2;
	uint32_t variable_id = offset + 3;

	SPIRType uint_type;
	uint_type.basetype = SPIRType::UInt;
	uint_type.width = 32;
	uint_type.vecsize = 3;
	uint_type.columns = 1;
	set<SPIRType>(uint_type_id, uint_type);

	SPIRType block_type;
	block_type.basetype = SPIRType::Struct;
	block_type.member_types.push_back(uint_type_id);
	set<SPIRType>(block_type_id, block_type);
	set_decoration(block_type_id, DecorationBlock);
	set_member_name(block_type_id, 0, "count");
	set_member_decoration(block_type_id, 0, DecorationOffset, 0);

	SPIRType block_pointer_type = block_type;
	block_pointer_type.pointer = true;
	block_pointer_type.storage = StorageClassUniform;
	block_pointer_type.parent_type = block_type_id;
	auto &ptr_type = set<SPIRType>(block_pointer_type_id, block_pointer_type);

	// Preserve self.
	ptr_type.self = block_type_id;

	set<SPIRVariable>(variable_id, block_pointer_type_id, StorageClassUniform);
	ir.meta[variable_id].decoration.alias = "SPIRV_Cross_NumWorkgroups";

	num_workgroups_builtin = variable_id;
	get_entry_point().interface_variables.push_back(num_workgroups_builtin);
	return variable_id;
}

void CompilerHLSL::set_resource_binding_flags(HLSLBindingFlags flags)
{
	resource_binding_flags = flags;
}

string CompilerHLSL::get_unique_identifier()
{
	return join("_", unique_identifier_count++, "ident");
}

void CompilerHLSL::add_hlsl_resource_binding(const HLSLResourceBinding &binding)
{
	StageSetBinding tuple = { binding.stage, binding.desc_set, binding.binding };
	resource_bindings[tuple] = { binding, false };
}

bool CompilerHLSL::is_hlsl_resource_binding_used(ExecutionModel model, uint32_t desc_set, uint32_t binding) const
{
	StageSetBinding tuple = { model, desc_set, binding };
	auto itr = resource_bindings.find(tuple);
	return itr != end(resource_bindings) && itr->second.second;
}

CompilerHLSL::BitcastType CompilerHLSL::get_bitcast_type(uint32_t result_type, uint32_t op0)
{
	auto &rslt_type = get<SPIRType>(result_type);
	auto &expr_type = expression_type(op0);

	if (rslt_type.basetype == SPIRType::BaseType::UInt64 && expr_type.basetype == SPIRType::BaseType::UInt &&
	    expr_type.vecsize == 2)
		return BitcastType::TypePackUint2x32;
	else if (rslt_type.basetype == SPIRType::BaseType::UInt && rslt_type.vecsize == 2 &&
	         expr_type.basetype == SPIRType::BaseType::UInt64)
		return BitcastType::TypeUnpackUint64;

	return BitcastType::TypeNormal;
}

bool CompilerHLSL::is_hlsl_force_storage_buffer_as_uav(ID id) const
{
	if (hlsl_options.force_storage_buffer_as_uav)
	{
		return true;
	}

	const uint32_t desc_set = get_decoration(id, spv::DecorationDescriptorSet);
	const uint32_t binding = get_decoration(id, spv::DecorationBinding);

	return (force_uav_buffer_bindings.find({ desc_set, binding }) != force_uav_buffer_bindings.end());
}

void CompilerHLSL::set_hlsl_force_storage_buffer_as_uav(uint32_t desc_set, uint32_t binding)
{
	SetBindingPair pair = { desc_set, binding };
	force_uav_buffer_bindings.insert(pair);
}

string CompilerHLSL::constant_op_expression(const SPIRConstantOp &cop)
{
	auto &type = get<SPIRType>(cop.basetype);
	bool binary = false;
	bool unary = false;
	string op;

	if (is_legacy() && is_unsigned_opcode(cop.opcode))
		SPIRV_CROSS_THROW("Unsigned integers are not supported on legacy targets.");

	// TODO: Find a clean way to reuse emit_instruction.
	switch (cop.opcode)
	{
	case OpSConvert:
	case OpUConvert:
	case OpFConvert:
		op = type_to_glsl_constructor(type);
		break;

#define GLSL_BOP(opname, x) \
	case Op##opname:        \
		binary = true;      \
		op = x;             \
		break

#define GLSL_UOP(opname, x) \
	case Op##opname:        \
		unary = true;       \
		op = x;             \
		break

		GLSL_UOP(SNegate, "-");
		GLSL_UOP(Not, "~");
		GLSL_BOP(IAdd, "+");
		GLSL_BOP(ISub, "-");
		GLSL_BOP(IMul, "*");
		GLSL_BOP(SDiv, "/");
		GLSL_BOP(UDiv, "/");
		GLSL_BOP(UMod, "%");
		GLSL_BOP(SMod, "%");
		GLSL_BOP(ShiftRightLogical, ">>");
		GLSL_BOP(ShiftRightArithmetic, ">>");
		GLSL_BOP(ShiftLeftLogical, "<<");
		GLSL_BOP(BitwiseOr, "|");
		GLSL_BOP(BitwiseXor, "^");
		GLSL_BOP(BitwiseAnd, "&");
		GLSL_BOP(LogicalOr, "||");
		GLSL_BOP(LogicalAnd, "&&");
		GLSL_UOP(LogicalNot, "!");
		GLSL_BOP(LogicalEqual, "==");
		GLSL_BOP(LogicalNotEqual, "!=");
		GLSL_BOP(IEqual, "==");
		GLSL_BOP(INotEqual, "!=");
		GLSL_BOP(ULessThan, "<");
		GLSL_BOP(SLessThan, "<");
		GLSL_BOP(ULessThanEqual, "<=");
		GLSL_BOP(SLessThanEqual, "<=");
		GLSL_BOP(UGreaterThan, ">");
		GLSL_BOP(SGreaterThan, ">");
		GLSL_BOP(UGreaterThanEqual, ">=");
		GLSL_BOP(SGreaterThanEqual, ">=");

	case OpSRem:
	{
		uint32_t op0 = cop.arguments[0];
		uint32_t op1 = cop.arguments[1];
		return join(to_enclosed_expression(op0), " - ", to_enclosed_expression(op1), " * ", "(",
		                 to_enclosed_expression(op0), " / ", to_enclosed_expression(op1), ")");
	}

	case OpSelect:
	{
		if (cop.arguments.size() < 3)
			SPIRV_CROSS_THROW("Not enough arguments to OpSpecConstantOp.");

		// This one is pretty annoying. It's triggered from
		// uint(bool), int(bool) from spec constants.
		// In order to preserve its compile-time constness in Vulkan GLSL,
		// we need to reduce the OpSelect expression back to this simplified model.
		// If we cannot, fail.
		if (to_trivial_mix_op(type, op, cop.arguments[2], cop.arguments[1], cop.arguments[0]))
		{
			// Implement as a simple cast down below.
		}
		else
		{
			// Implement a ternary and pray the compiler understands it :)
			return to_ternary_expression(type, cop.arguments[0], cop.arguments[1], cop.arguments[2]);
		}
		break;
	}

	case OpVectorShuffle:
	{
		string expr = type_to_glsl_constructor(type);
		expr += "(";

		uint32_t left_components = expression_type(cop.arguments[0]).vecsize;
		string left_arg = to_enclosed_expression(cop.arguments[0]);
		string right_arg = to_enclosed_expression(cop.arguments[1]);

		for (uint32_t i = 2; i < uint32_t(cop.arguments.size()); i++)
		{
			uint32_t index = cop.arguments[i];
			if (index == 0xFFFFFFFF)
			{
				SPIRConstant c;
				c.constant_type = type.parent_type;
				assert(type.parent_type != ID(0));
				expr += constant_expression(c);
			}
			else if (index >= left_components)
			{
				expr += right_arg + "." + "xyzw"[index - left_components];
			}
			else
			{
				expr += left_arg + "." + "xyzw"[index];
			}

			if (i + 1 < uint32_t(cop.arguments.size()))
				expr += ", ";
		}

		expr += ")";
		return expr;
	}

	case OpCompositeExtract:
	{
		auto expr = access_chain_internal(cop.arguments[0], &cop.arguments[1], uint32_t(cop.arguments.size() - 1),
		                                  ACCESS_CHAIN_INDEX_IS_LITERAL_BIT, nullptr);
		return expr;
	}

	case OpCompositeInsert:
	{
		SmallVector<ConstantID> new_init = get_composite_constant_ids(cop.arguments[1]);
		uint32_t idx;
		uint32_t target_id = cop.self;
		uint32_t target_type_id = cop.basetype;
		// We have to drill down to the part we want to modify, and create new
		// constants for each containing part.
		for (idx = 2; idx < cop.arguments.size() - 1; ++idx)
		{
			uint32_t new_const = ir.increase_bound_by(1);
			uint32_t old_const = new_init[cop.arguments[idx]];
			new_init[cop.arguments[idx]] = new_const;
			set_composite_constant(target_id, target_type_id, new_init);
			new_init = get_composite_constant_ids(old_const);
			target_id = new_const;
			target_type_id = get_composite_member_type(target_type_id, cop.arguments[idx]);
		}
		// Now replace the initializer with the one from this instruction.
		new_init[cop.arguments[idx]] = cop.arguments[0];
		set_composite_constant(target_id, target_type_id, new_init);
		SPIRConstant tmp_const(cop.basetype);
		fill_composite_constant(tmp_const, cop.basetype, const_composite_insert_ids[cop.self]);
		return constant_expression(tmp_const);
	}

	default:
		// Some opcodes are unimplemented here, these are currently not possible to test from glslang.
		SPIRV_CROSS_THROW("Unimplemented spec constant op.");
	}

	uint32_t bit_width = 0;
	if (unary || binary || cop.opcode == OpSConvert || cop.opcode == OpUConvert)
		bit_width = expression_type(cop.arguments[0]).width;

	SPIRType::BaseType input_type;
	bool skip_cast_if_equal_type = opcode_is_sign_invariant(cop.opcode);

	switch (cop.opcode)
	{
	case OpIEqual:
	case OpINotEqual:
		input_type = to_signed_basetype(bit_width);
		break;

	case OpSLessThan:
	case OpSLessThanEqual:
	case OpSGreaterThan:
	case OpSGreaterThanEqual:
	case OpSMod:
	case OpSDiv:
	case OpShiftRightArithmetic:
	case OpSConvert:
	case OpSNegate:
		input_type = to_signed_basetype(bit_width);
		break;

	case OpULessThan:
	case OpULessThanEqual:
	case OpUGreaterThan:
	case OpUGreaterThanEqual:
	case OpUMod:
	case OpUDiv:
	case OpShiftRightLogical:
	case OpUConvert:
		input_type = to_unsigned_basetype(bit_width);
		break;

	default:
		input_type = type.basetype;
		break;
	}

#undef GLSL_BOP
#undef GLSL_UOP
	if (binary)
	{
		if (cop.arguments.size() < 2)
			SPIRV_CROSS_THROW("Not enough arguments to OpSpecConstantOp.");

		string cast_op0;
		string cast_op1;
		auto expected_type = binary_op_bitcast_helper(cast_op0, cast_op1, input_type, cop.arguments[0],
		                                              cop.arguments[1], skip_cast_if_equal_type);

		if (type.basetype != input_type && type.basetype != SPIRType::Boolean)
		{
			expected_type.basetype = input_type;
			auto expr = bitcast_glsl_op(type, expected_type);
			expr += '(';
			expr += join(cast_op0, " ", op, " ", cast_op1);
			expr += ')';
			return expr;
		}
		else
			return join("(", cast_op0, " ", op, " ", cast_op1, ")");
	}
	else if (unary)
	{
		if (cop.arguments.size() < 1)
			SPIRV_CROSS_THROW("Not enough arguments to OpSpecConstantOp.");

		// Auto-bitcast to result type as needed.
		// Works around various casting scenarios in glslang as there is no OpBitcast for specialization constants.
		return join("(", op, bitcast_glsl(type, cop.arguments[0]), ")");
	}
	else if (cop.opcode == OpSConvert || cop.opcode == OpUConvert)
	{
		if (cop.arguments.size() < 1)
			SPIRV_CROSS_THROW("Not enough arguments to OpSpecConstantOp.");

		auto &arg_type = expression_type(cop.arguments[0]);
		if (arg_type.width < type.width && input_type != arg_type.basetype)
		{
			auto expected = arg_type;
			expected.basetype = input_type;
			return join(op, "(", bitcast_glsl(expected, cop.arguments[0]), ")");
		}
		else
			return join(op, "(", to_expression(cop.arguments[0]), ")");
	}
	else
	{
		if (cop.arguments.size() < 1)
			SPIRV_CROSS_THROW("Not enough arguments to OpSpecConstantOp.");
		return join(op, "(", to_expression(cop.arguments[0]), ")");
	}
}

bool CompilerHLSL::type_can_zero_initialize(const SPIRType &type) const
{
	if (type.pointer)
		return false;

	if (!type.array.empty() && options.flatten_multidimensional_arrays)
		return false;

	for (auto &literal : type.array_size_literal)
		if (!literal)
			return false;

	for (auto &memb : type.member_types)
		if (!type_can_zero_initialize(get<SPIRType>(memb)))
			return false;

	return true;
}

string CompilerHLSL::to_zero_initialized_expression(uint32_t type_id)
{
#ifndef NDEBUG
	auto &type = get<SPIRType>(type_id);
	assert(type.storage == StorageClassPrivate || type.storage == StorageClassFunction ||
	       type.storage == StorageClassGeneric);
#endif
	uint32_t id = ir.increase_bound_by(1);
	ir.make_constant_null(id, type_id, false);
	return constant_expression(get<SPIRConstant>(id));
}

void CompilerHLSL::fixup_implicit_builtin_block_names(ExecutionModel model)
{
	ir.for_each_typed_id<SPIRVariable>([&](uint32_t, SPIRVariable &var) {
		auto &type = this->get<SPIRType>(var.basetype);
		bool block = has_decoration(type.self, DecorationBlock);
		if ((var.storage == StorageClassOutput || var.storage == StorageClassInput) && block &&
		    is_builtin_variable(var))
		{
			if (model != ExecutionModelMeshEXT)
			{
				// Make sure the array has a supported name in the code.
				if (var.storage == StorageClassOutput)
					set_name(var.self, "gl_out");
				else if (var.storage == StorageClassInput)
					set_name(var.self, "gl_in");
			}
			else
			{
				auto flags = get_buffer_block_flags(var.self);
				if (flags.get(DecorationPerPrimitiveEXT))
				{
					set_name(var.self, "gl_MeshPrimitivesEXT");
					set_name(type.self, "gl_MeshPerPrimitiveEXT");
				}
				else
				{
					set_name(var.self, "gl_MeshVerticesEXT");
					set_name(type.self, "gl_MeshPerVertexEXT");
				}
			}
		}

		if (model == ExecutionModelMeshEXT && var.storage == StorageClassOutput && !block)
		{
			auto *m = ir.find_meta(var.self);
			if (m && m->decoration.builtin)
			{
				auto builtin_type = m->decoration.builtin_type;
				if (builtin_type == BuiltInPrimitivePointIndicesEXT)
					set_name(var.self, "gl_PrimitivePointIndicesEXT");
				else if (builtin_type == BuiltInPrimitiveLineIndicesEXT)
					set_name(var.self, "gl_PrimitiveLineIndicesEXT");
				else if (builtin_type == BuiltInPrimitiveTriangleIndicesEXT)
					set_name(var.self, "gl_PrimitiveTriangleIndicesEXT");
			}
		}
	});
}

uint32_t CompilerHLSL::get_declared_member_location(const SPIRVariable &var, uint32_t mbr_idx, bool strip_array) const
{
	auto &block_type = get<SPIRType>(var.basetype);
	if (has_member_decoration(block_type.self, mbr_idx, DecorationLocation))
		return get_member_decoration(block_type.self, mbr_idx, DecorationLocation);
	else
		return get_accumulated_member_location(var, mbr_idx, strip_array);
}

void CompilerHLSL::emit_buffer_block_flattened(const SPIRVariable &var)
{
	auto &type = get<SPIRType>(var.basetype);

	// Block names should never alias.
	auto buffer_name = to_name(type.self, false);
	size_t buffer_size = (get_declared_struct_size(type) + 15) / 16;

	SPIRType::BaseType basic_type;
	if (get_common_basic_type(type, basic_type))
	{
		SPIRType tmp;
		tmp.basetype = basic_type;
		tmp.vecsize = 4;
		if (basic_type != SPIRType::Float && basic_type != SPIRType::Int && basic_type != SPIRType::UInt)
			SPIRV_CROSS_THROW("Basic types in a flattened UBO must be float, int or uint.");

		auto flags = ir.get_buffer_block_flags(var);
		statement("uniform ", flags_to_qualifiers_glsl(tmp, flags), type_to_glsl(tmp), " ", buffer_name, "[",
		          buffer_size, "];");
	}
	else
		SPIRV_CROSS_THROW("All basic types in a flattened block must be the same.");
}

string CompilerHLSL::to_combined_image_sampler(VariableID image_id, VariableID samp_id)
{
	// Keep track of the array indices we have used to load the image.
	// We'll need to use the same array index into the combined image sampler array.
	auto image_expr = to_non_uniform_aware_expression(image_id);
	string array_expr;
	auto array_index = image_expr.find_first_of('[');
	if (array_index != string::npos)
		array_expr = image_expr.substr(array_index, string::npos);

	auto &args = current_function->arguments;

	// For GLSL and ESSL targets, we must enumerate all possible combinations for sampler2D(texture2D, sampler) and redirect
	// all possible combinations into new sampler2D uniforms.
	auto *image = maybe_get_backing_variable(image_id);
	auto *samp = maybe_get_backing_variable(samp_id);
	if (image)
		image_id = image->self;
	if (samp)
		samp_id = samp->self;

	auto image_itr = find_if(begin(args), end(args),
	                         [image_id](const SPIRFunction::Parameter &param) { return image_id == param.id; });

	auto sampler_itr = find_if(begin(args), end(args),
	                           [samp_id](const SPIRFunction::Parameter &param) { return samp_id == param.id; });

	if (image_itr != end(args) || sampler_itr != end(args))
	{
		// If any parameter originates from a parameter, we will find it in our argument list.
		bool global_image = image_itr == end(args);
		bool global_sampler = sampler_itr == end(args);
		VariableID iid = global_image ? image_id : VariableID(uint32_t(image_itr - begin(args)));
		VariableID sid = global_sampler ? samp_id : VariableID(uint32_t(sampler_itr - begin(args)));

		auto &combined = current_function->combined_parameters;
		auto itr = find_if(begin(combined), end(combined), [=](const SPIRFunction::CombinedImageSamplerParameter &p) {
			return p.global_image == global_image && p.global_sampler == global_sampler && p.image_id == iid &&
			       p.sampler_id == sid;
		});

		if (itr != end(combined))
			return to_expression(itr->id) + array_expr;
		else
		{
			SPIRV_CROSS_THROW("Cannot find mapping for combined sampler parameter, was "
			                  "build_combined_image_samplers() used "
			                  "before compile() was called?");
		}
	}
	else
	{
		// For global sampler2D, look directly at the global remapping table.
		auto &mapping = combined_image_samplers;
		auto itr = find_if(begin(mapping), end(mapping), [image_id, samp_id](const CombinedImageSampler &combined) {
			return combined.image_id == image_id && combined.sampler_id == samp_id;
		});

		if (itr != end(combined_image_samplers))
			return to_expression(itr->combined_id) + array_expr;
		else
		{
			SPIRV_CROSS_THROW("Cannot find mapping for combined sampler, was build_combined_image_samplers() used "
			                  "before compile() was called?");
		}
	}
}

string CompilerHLSL::to_extract_component_expression(uint32_t id, uint32_t index)
{
	auto expr = to_enclosed_expression(id);
	if (has_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked))
		return join(expr, "[", index, "]");
	else
		return join(expr, ".", index_to_swizzle(index));
}

void CompilerHLSL::emit_emulated_ahyper_op(uint32_t result_type, uint32_t id, uint32_t op0, GLSLstd450 op)
{
	const char *one = backend.float_literal_suffix ? "1.0f" : "1.0";
	std::string expr;
	bool forward = should_forward(op0);

	switch (op)
	{
	case GLSLstd450Asinh:
		expr = join("log(", to_enclosed_expression(op0), " + sqrt(",
		            to_enclosed_expression(op0), " * ", to_enclosed_expression(op0), " + ", one, "))");
		emit_op(result_type, id, expr, forward);
		break;

	case GLSLstd450Acosh:
		expr = join("log(", to_enclosed_expression(op0), " + sqrt(",
		            to_enclosed_expression(op0), " * ", to_enclosed_expression(op0), " - ", one, "))");
		break;

	case GLSLstd450Atanh:
		expr = join("log((", one, " + ", to_enclosed_expression(op0), ") / "
		            "(", one, " - ", to_enclosed_expression(op0), ")) * 0.5",
		            backend.float_literal_suffix ? "f" : "");
		break;

	default:
		SPIRV_CROSS_THROW("Invalid op.");
	}

	emit_op(result_type, id, expr, forward);
	inherit_expression_dependencies(id, op0);
}

void CompilerHLSL::convert_non_uniform_expression(string &expr, uint32_t ptr_id)
{
	if (*backend.nonuniform_qualifier == '\0')
		return;

	auto *var = maybe_get_backing_variable(ptr_id);
	if (!var)
		return;

	if (var->storage != StorageClassUniformConstant &&
	    var->storage != StorageClassStorageBuffer &&
	    var->storage != StorageClassUniform)
		return;

	auto &backing_type = get<SPIRType>(var->basetype);
	if (backing_type.array.empty())
		return;

	// If we get here, we know we're accessing an arrayed resource which
	// might require nonuniform qualifier.

	auto start_array_index = expr.find_first_of('[');

	if (start_array_index == string::npos)
		return;

	// We've opened a bracket, track expressions until we can close the bracket.
	// This must be our resource index.
	size_t end_array_index = string::npos;
	unsigned bracket_count = 1;
	for (size_t index = start_array_index + 1; index < expr.size(); index++)
	{
		if (expr[index] == ']')
		{
			if (--bracket_count == 0)
			{
				end_array_index = index;
				break;
			}
		}
		else if (expr[index] == '[')
			bracket_count++;
	}

	assert(bracket_count == 0);

	// Doesn't really make sense to declare a non-arrayed image with nonuniformEXT, but there's
	// nothing we can do here to express that.
	if (start_array_index == string::npos || end_array_index == string::npos || end_array_index < start_array_index)
		return;

	start_array_index++;

	expr = join(expr.substr(0, start_array_index), backend.nonuniform_qualifier, "(",
	            expr.substr(start_array_index, end_array_index - start_array_index), ")",
	            expr.substr(end_array_index, string::npos));
}

SPIRExpression &CompilerHLSL::emit_uninitialized_temporary_expression(uint32_t type, uint32_t id)
{
	forced_temporaries.insert(id);
	emit_uninitialized_temporary(type, id);
	return set<SPIRExpression>(id, to_name(id), type, true);
}

std::pair<std::string, uint32_t> CompilerHLSL::flattened_access_chain_offset(
    const SPIRType &basetype, const uint32_t *indices, uint32_t count, uint32_t offset, uint32_t word_stride,
    bool *need_transpose, uint32_t *out_matrix_stride, uint32_t *out_array_stride, bool ptr_chain)
{
	// Start traversing type hierarchy at the proper non-pointer types.
	const auto *type = &get_pointee_type(basetype);

	std::string expr;

	// Inherit matrix information in case we are access chaining a vector which might have come from a row major layout.
	bool row_major_matrix_needs_conversion = need_transpose ? *need_transpose : false;
	uint32_t matrix_stride = out_matrix_stride ? *out_matrix_stride : 0;
	uint32_t array_stride = out_array_stride ? *out_array_stride : 0;

	for (uint32_t i = 0; i < count; i++)
	{
		uint32_t index = indices[i];

		// Pointers
		if (ptr_chain && i == 0)
		{
			// Here, the pointer type will be decorated with an array stride.
			array_stride = get_decoration(basetype.self, DecorationArrayStride);
			if (!array_stride)
				SPIRV_CROSS_THROW("SPIR-V does not define ArrayStride for buffer block.");

			auto *constant = maybe_get<SPIRConstant>(index);
			if (constant)
			{
				// Constant array access.
				offset += constant->scalar() * array_stride;
			}
			else
			{
				// Dynamic array access.
				if (array_stride % word_stride)
				{
					SPIRV_CROSS_THROW("Array stride for dynamic indexing must be divisible by the size "
					                  "of a 4-component vector. "
					                  "Likely culprit here is a float or vec2 array inside a push "
					                  "constant block which is std430. "
					                  "This cannot be flattened. Try using std140 layout instead.");
				}

				expr += to_enclosed_expression(index);
				expr += " * ";
				expr += convert_to_string(array_stride / word_stride);
				expr += " + ";
			}
		}
		// Arrays
		else if (!type->array.empty())
		{
			auto *constant = maybe_get<SPIRConstant>(index);
			if (constant)
			{
				// Constant array access.
				offset += constant->scalar() * array_stride;
			}
			else
			{
				// Dynamic array access.
				if (array_stride % word_stride)
				{
					SPIRV_CROSS_THROW("Array stride for dynamic indexing must be divisible by the size "
					                  "of a 4-component vector. "
					                  "Likely culprit here is a float or vec2 array inside a push "
					                  "constant block which is std430. "
					                  "This cannot be flattened. Try using std140 layout instead.");
				}

				expr += to_enclosed_expression(index, false);
				expr += " * ";
				expr += convert_to_string(array_stride / word_stride);
				expr += " + ";
			}

			uint32_t parent_type = type->parent_type;
			type = &get<SPIRType>(parent_type);

			if (!type->array.empty())
				array_stride = get_decoration(parent_type, DecorationArrayStride);
		}
		// For structs, the index refers to a constant, which indexes into the members.
		// We also check if this member is a builtin, since we then replace the entire expression with the builtin one.
		else if (type->basetype == SPIRType::Struct)
		{
			index = evaluate_constant_u32(index);

			if (index >= type->member_types.size())
				SPIRV_CROSS_THROW("Member index is out of bounds!");

			offset += type_struct_member_offset(*type, index);

			auto &struct_type = *type;
			type = &get<SPIRType>(type->member_types[index]);

			if (type->columns > 1)
			{
				matrix_stride = type_struct_member_matrix_stride(struct_type, index);
				row_major_matrix_needs_conversion =
				    combined_decoration_for_member(struct_type, index).get(DecorationRowMajor);
			}
			else
				row_major_matrix_needs_conversion = false;

			if (!type->array.empty())
				array_stride = type_struct_member_array_stride(struct_type, index);
		}
		// Matrix -> Vector
		else if (type->columns > 1)
		{
			auto *constant = maybe_get<SPIRConstant>(index);
			if (constant)
			{
				index = evaluate_constant_u32(index);
				offset += index * (row_major_matrix_needs_conversion ? (type->width / 8) : matrix_stride);
			}
			else
			{
				uint32_t indexing_stride = row_major_matrix_needs_conversion ? (type->width / 8) : matrix_stride;
				// Dynamic array access.
				if (indexing_stride % word_stride)
				{
					SPIRV_CROSS_THROW("Matrix stride for dynamic indexing must be divisible by the size of a "
					                  "4-component vector. "
					                  "Likely culprit here is a row-major matrix being accessed dynamically. "
					                  "This cannot be flattened. Try using std140 layout instead.");
				}

				expr += to_enclosed_expression(index, false);
				expr += " * ";
				expr += convert_to_string(indexing_stride / word_stride);
				expr += " + ";
			}

			type = &get<SPIRType>(type->parent_type);
		}
		// Vector -> Scalar
		else if (type->vecsize > 1)
		{
			auto *constant = maybe_get<SPIRConstant>(index);
			if (constant)
			{
				index = evaluate_constant_u32(index);
				offset += index * (row_major_matrix_needs_conversion ? matrix_stride : (type->width / 8));
			}
			else
			{
				uint32_t indexing_stride = row_major_matrix_needs_conversion ? matrix_stride : (type->width / 8);

				// Dynamic array access.
				if (indexing_stride % word_stride)
				{
					SPIRV_CROSS_THROW("Stride for dynamic vector indexing must be divisible by the "
					                  "size of a 4-component vector. "
					                  "This cannot be flattened in legacy targets.");
				}

				expr += to_enclosed_expression(index, false);
				expr += " * ";
				expr += convert_to_string(indexing_stride / word_stride);
				expr += " + ";
			}

			type = &get<SPIRType>(type->parent_type);
		}
		else
			SPIRV_CROSS_THROW("Cannot subdivide a scalar value!");
	}

	if (need_transpose)
		*need_transpose = row_major_matrix_needs_conversion;
	if (out_matrix_stride)
		*out_matrix_stride = matrix_stride;
	if (out_array_stride)
		*out_array_stride = array_stride;

	return std::make_pair(expr, offset);
}

std::string CompilerHLSL::bitcast_expression(SPIRType::BaseType target_type, uint32_t arg)
{
	auto expr = to_expression(arg);
	auto &src_type = expression_type(arg);
	if (src_type.basetype != target_type)
	{
		auto target = src_type;
		target.basetype = target_type;
		expr = join(bitcast_glsl_op(target, src_type), "(", expr, ")");
	}

	return expr;
}

std::string CompilerHLSL::bitcast_expression(const SPIRType &target_type, SPIRType::BaseType expr_type,
                                             const std::string &expr)
{
	if (target_type.basetype == expr_type)
		return expr;

	auto src_type = target_type;
	src_type.basetype = expr_type;
	return join(bitcast_glsl_op(target_type, src_type), "(", expr, ")");
}

void CompilerHLSL::emit_unrolled_unary_op(uint32_t result_type, uint32_t result_id, uint32_t operand, const char *op)
{
	auto &type = get<SPIRType>(result_type);
	auto expr = type_to_glsl_constructor(type);
	expr += '(';
	for (uint32_t i = 0; i < type.vecsize; i++)
	{
		// Make sure to call to_expression multiple times to ensure
		// that these expressions are properly flushed to temporaries if needed.
		expr += op;
		expr += to_extract_component_expression(operand, i);

		if (i + 1 < type.vecsize)
			expr += ", ";
	}
	expr += ')';
	emit_op(result_type, result_id, expr, should_forward(operand));

	inherit_expression_dependencies(result_id, operand);
}

void CompilerHLSL::emit_unrolled_binary_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                           const char *op, bool negate, SPIRType::BaseType expected_type)
{
	auto &type0 = expression_type(op0);
	auto &type1 = expression_type(op1);

	SPIRType target_type0 = type0;
	SPIRType target_type1 = type1;
	target_type0.basetype = expected_type;
	target_type1.basetype = expected_type;
	target_type0.vecsize = 1;
	target_type1.vecsize = 1;

	auto &type = get<SPIRType>(result_type);
	auto expr = type_to_glsl_constructor(type);
	expr += '(';
	for (uint32_t i = 0; i < type.vecsize; i++)
	{
		// Make sure to call to_expression multiple times to ensure
		// that these expressions are properly flushed to temporaries if needed.
		if (negate)
			expr += "!(";

		if (expected_type != SPIRType::Unknown && type0.basetype != expected_type)
			expr += bitcast_expression(target_type0, type0.basetype, to_extract_component_expression(op0, i));
		else
			expr += to_extract_component_expression(op0, i);

		expr += ' ';
		expr += op;
		expr += ' ';

		if (expected_type != SPIRType::Unknown && type1.basetype != expected_type)
			expr += bitcast_expression(target_type1, type1.basetype, to_extract_component_expression(op1, i));
		else
			expr += to_extract_component_expression(op1, i);

		if (negate)
			expr += ")";

		if (i + 1 < type.vecsize)
			expr += ", ";
	}
	expr += ')';
	emit_op(result_type, result_id, expr, should_forward(op0) && should_forward(op1));

	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
}

uint32_t CompilerHLSL::mask_relevant_memory_semantics(uint32_t semantics)
{
	return semantics & (MemorySemanticsAtomicCounterMemoryMask | MemorySemanticsImageMemoryMask |
	                    MemorySemanticsWorkgroupMemoryMask | MemorySemanticsUniformMemoryMask |
	                    MemorySemanticsCrossWorkgroupMemoryMask | MemorySemanticsSubgroupMemoryMask);
}

const Instruction *CompilerHLSL::get_next_instruction_in_block(const Instruction &instr)
{
	// FIXME: This is kind of hacky. There should be a cleaner way.
	auto offset = uint32_t(&instr - current_emitting_block->ops.data());
	if ((offset + 1) < current_emitting_block->ops.size())
		return &current_emitting_block->ops[offset + 1];
	else
		return nullptr;
}

void CompilerHLSL::emit_line_directive(uint32_t file_id, uint32_t line_literal)
{
	// If we are redirecting statements, ignore the line directive.
	// Common case here is continue blocks.
	if (redirect_statement)
		return;

	// If we're emitting code in a sensitive context such as condition blocks in for loops, don't emit
	// any line directives, because it's not possible.
	if (block_debug_directives)
		return;

	if (options.emit_line_directives)
	{
		require_extension_internal("GL_GOOGLE_cpp_style_line_directive");
		statement_no_indent("#line ", line_literal, " \"", get<SPIRString>(file_id).str, "\"");
	}
}

void CompilerHLSL::emit_while_loop_initializers(const SPIRBlock &block)
{
	// While loops do not take initializers, so declare all of them outside.
	for (auto &loop_var : block.loop_variables)
	{
		auto &var = get<SPIRVariable>(loop_var);
		statement(variable_decl(var), ";");
	}
}


string CompilerHLSL::address_of_expression(const std::string &expr)
{
	if (expr.size() > 3 && expr[0] == '(' && expr[1] == '*' && expr.back() == ')')
	{
		// If we have an expression which looks like (*foo), taking the address of it is the same as stripping
		// the first two and last characters. We might have to enclose the expression.
		// This doesn't work for cases like (*foo + 10),
		// but this is an r-value expression which we cannot take the address of anyways.
		return enclose_expression(expr.substr(2, expr.size() - 3));
	}
	else if (expr.front() == '*')
	{
		// If this expression starts with a dereference operator ('*'), then
		// just return the part after the operator.
		return expr.substr(1);
	}
	else
		return join('&', enclose_expression(expr));
}

bool CompilerHLSL::emit_array_copy(const char *expr, uint32_t lhs_id, uint32_t rhs_id, StorageClass, StorageClass)
{
	string lhs;
	if (expr)
		lhs = expr;
	else
		lhs = to_expression(lhs_id);

	statement(lhs, " = ", to_expression(rhs_id), ";");
	return true;
}

void CompilerHLSL::analyze_precision_requirements(uint32_t type_id, uint32_t dst_id, uint32_t *args, uint32_t length)
{
	if (!backend.requires_relaxed_precision_analysis)
		return;

	auto &type = get<SPIRType>(type_id);

	// RelaxedPrecision only applies to 32-bit values.
	if (type.basetype != SPIRType::Float && type.basetype != SPIRType::Int && type.basetype != SPIRType::UInt)
		return;

	bool operation_is_highp = !has_decoration(dst_id, DecorationRelaxedPrecision);

	auto input_precision = analyze_expression_precision(args, length);
	if (input_precision == OptionsGLSL::DontCare)
	{
		consume_temporary_in_precision_context(type_id, dst_id, input_precision);
		return;
	}

	// In SPIR-V and GLSL, the semantics are flipped for how relaxed precision is determined.
	// In SPIR-V, the operation itself marks RelaxedPrecision, meaning that inputs can be truncated to 16-bit.
	// However, if the expression is not, inputs must be expanded to 32-bit first,
	// since the operation must run at high precision.
	// This is the awkward part, because if we have mediump inputs, or expressions which derived from mediump,
	// we might have to forcefully bind the source IDs to highp temporaries. This is done by clearing decorations
	// and forcing temporaries. Similarly for mediump operations. We bind highp expressions to mediump variables.
	if ((operation_is_highp && input_precision == OptionsGLSL::Mediump) ||
	    (!operation_is_highp && input_precision == OptionsGLSL::Highp))
	{
		auto precision = operation_is_highp ? OptionsGLSL::Highp : OptionsGLSL::Mediump;
		for (uint32_t i = 0; i < length; i++)
		{
			// Rewrites the opcode so that we consume an ID in correct precision context.
			// This is pretty hacky, but it's the most straight forward way of implementing this without adding
			// lots of extra passes to rewrite all code blocks.
			args[i] = consume_temporary_in_precision_context(expression_type_id(args[i]), args[i], precision);
		}
	}
}

CompilerHLSL::OptionsGLSL::Precision CompilerHLSL::analyze_expression_precision(const uint32_t *args, uint32_t length) const
{
	// Now, analyze the precision at which the arguments would run.
	// GLSL rules are such that the precision used to evaluate an expression is equal to the highest precision
	// for the inputs. Constants do not have inherent precision and do not contribute to this decision.
	// If all inputs are constants, they inherit precision from outer expressions, including an l-value.
	// In this case, we'll have to force a temporary for dst_id so that we can bind the constant expression with
	// correct precision.
	bool expression_has_highp = false;
	bool expression_has_mediump = false;

	for (uint32_t i = 0; i < length; i++)
	{
		uint32_t arg = args[i];

		auto handle_type = ir.ids[arg].get_type();
		if (handle_type == TypeConstant || handle_type == TypeConstantOp || handle_type == TypeUndef)
			continue;

		if (has_decoration(arg, DecorationRelaxedPrecision))
			expression_has_mediump = true;
		else
			expression_has_highp = true;
	}

	if (expression_has_highp)
		return OptionsGLSL::Highp;
	else if (expression_has_mediump)
		return OptionsGLSL::Mediump;
	else
		return OptionsGLSL::DontCare;
}

uint32_t CompilerHLSL::consume_temporary_in_precision_context(uint32_t type_id, uint32_t id, OptionsGLSL::Precision precision)
{
	// Constants do not have innate precision.
	auto handle_type = ir.ids[id].get_type();
	if (handle_type == TypeConstant || handle_type == TypeConstantOp || handle_type == TypeUndef)
		return id;

	// Ignore anything that isn't 32-bit values.
	auto &type = get<SPIRType>(type_id);
	if (type.pointer)
		return id;
	if (type.basetype != SPIRType::Float && type.basetype != SPIRType::UInt && type.basetype != SPIRType::Int)
		return id;

	if (precision == OptionsGLSL::DontCare)
	{
		// If precision is consumed as don't care (operations only consisting of constants),
		// we need to bind the expression to a temporary,
		// otherwise we have no way of controlling the precision later.
		auto itr = forced_temporaries.insert(id);
		if (itr.second)
			force_recompile_guarantee_forward_progress();
		return id;
	}

	auto current_precision = has_decoration(id, DecorationRelaxedPrecision) ? OptionsGLSL::Mediump : OptionsGLSL::Highp;
	if (current_precision == precision)
		return id;

	auto itr = temporary_to_mirror_precision_alias.find(id);
	if (itr == temporary_to_mirror_precision_alias.end())
	{
		uint32_t alias_id = ir.increase_bound_by(1);
		auto &m = ir.meta[alias_id];
		if (auto *input_m = ir.find_meta(id))
			m = *input_m;

		const char *prefix;
		if (precision == OptionsGLSL::Mediump)
		{
			set_decoration(alias_id, DecorationRelaxedPrecision);
			prefix = "mp_copy_";
		}
		else
		{
			unset_decoration(alias_id, DecorationRelaxedPrecision);
			prefix = "hp_copy_";
		}

		auto alias_name = join(prefix, to_name(id));
		ParsedIR::sanitize_underscores(alias_name);
		set_name(alias_id, alias_name);

		emit_op(type_id, alias_id, to_expression(id), true);
		temporary_to_mirror_precision_alias[id] = alias_id;
		forced_temporaries.insert(id);
		forced_temporaries.insert(alias_id);
		force_recompile_guarantee_forward_progress();
		id = alias_id;
	}
	else
	{
		id = itr->second;
	}

	return id;
}

void CompilerHLSL::forward_relaxed_precision(uint32_t dst_id, const uint32_t *args, uint32_t length)
{
	// Only GLSL supports RelaxedPrecision directly.
	// We cannot implement this in HLSL or MSL because it is tied to the type system.
	// In SPIR-V, everything must masquerade as 32-bit.
	if (!backend.requires_relaxed_precision_analysis)
		return;

	auto input_precision = analyze_expression_precision(args, length);

	// For expressions which are loaded or directly forwarded, we inherit mediump implicitly.
	// For dst_id to be analyzed properly, it must inherit any relaxed precision decoration from src_id.
	if (input_precision == OptionsGLSL::Mediump)
		set_decoration(dst_id, DecorationRelaxedPrecision);
}


string CompilerHLSL::convert_half_to_string(const SPIRConstant &c, uint32_t col, uint32_t row)
{
	string res;
	float float_value = c.scalar_f16(col, row);

	// There is no literal "hf" in GL_NV_gpu_shader5, so to avoid lots
	// of complicated workarounds, just value-cast to the half type always.
	if (std::isnan(float_value) || std::isinf(float_value))
	{
		SPIRType type;
		type.basetype = SPIRType::Half;
		type.vecsize = 1;
		type.columns = 1;

		if (float_value == numeric_limits<float>::infinity())
			res = join(type_to_glsl(type), "(1.0 / 0.0)");
		else if (float_value == -numeric_limits<float>::infinity())
			res = join(type_to_glsl(type), "(-1.0 / 0.0)");
		else if (std::isnan(float_value))
			res = join(type_to_glsl(type), "(0.0 / 0.0)");
		else
			SPIRV_CROSS_THROW("Cannot represent non-finite floating point constant.");
	}
	else
	{
		SPIRType type;
		type.basetype = SPIRType::Half;
		type.vecsize = 1;
		type.columns = 1;
		res = join(type_to_glsl(type), "(", convert_to_string(float_value, current_locale_radix_character), ")");
	}

	return res;
}

std::string CompilerHLSL::convert_double_to_string(const SPIRConstant &c, uint32_t col, uint32_t row)
{
	string res;
	double double_value = c.scalar_f64(col, row);

	if (std::isnan(double_value) || std::isinf(double_value))
	{
		// Use special representation.
		if (!is_legacy())
		{
			SPIRType out_type;
			SPIRType in_type;
			out_type.basetype = SPIRType::Double;
			in_type.basetype = SPIRType::UInt64;
			out_type.vecsize = 1;
			in_type.vecsize = 1;
			out_type.width = 64;
			in_type.width = 64;

			uint64_t u64_value = c.scalar_u64(col, row);

			if (options.es && options.version < 310) // GL_NV_gpu_shader5 fallback requires 310.
				SPIRV_CROSS_THROW("64-bit integers not supported in ES profile before version 310.");
			require_extension_internal("GL_ARB_gpu_shader_int64");

			char print_buffer[64];
			snprintf(print_buffer, sizeof(print_buffer), "0x%llx%s", static_cast<unsigned long long>(u64_value),
			         backend.long_long_literal_suffix ? "ull" : "ul");

			const char *comment = "inf";
			if (double_value == -numeric_limits<double>::infinity())
				comment = "-inf";
			else if (std::isnan(double_value))
				comment = "nan";
			res = join(bitcast_glsl_op(out_type, in_type), "(", print_buffer, " /* ", comment, " */)");
		}
		else
		{
			if (options.es)
				SPIRV_CROSS_THROW("FP64 not supported in ES profile.");
			if (options.version < 400)
				require_extension_internal("GL_ARB_gpu_shader_fp64");

			if (double_value == numeric_limits<double>::infinity())
			{
				if (backend.double_literal_suffix)
					res = "(1.0lf / 0.0lf)";
				else
					res = "(1.0 / 0.0)";
			}
			else if (double_value == -numeric_limits<double>::infinity())
			{
				if (backend.double_literal_suffix)
					res = "(-1.0lf / 0.0lf)";
				else
					res = "(-1.0 / 0.0)";
			}
			else if (std::isnan(double_value))
			{
				if (backend.double_literal_suffix)
					res = "(0.0lf / 0.0lf)";
				else
					res = "(0.0 / 0.0)";
			}
			else
				SPIRV_CROSS_THROW("Cannot represent non-finite floating point constant.");
		}
	}
	else
	{
		res = convert_to_string(double_value, current_locale_radix_character);
		if (backend.double_literal_suffix)
			res += "lf";
	}

	return res;
}

void CompilerHLSL::require_extension_internal(const string &ext)
{
	if (backend.supports_extensions && !has_extension(ext))
	{
		forced_extensions.push_back(ext);
		force_recompile();
	}
}

bool CompilerHLSL::has_extension(const std::string &ext) const
{
	auto itr = find(begin(forced_extensions), end(forced_extensions), ext);
	return itr != end(forced_extensions);
}

// Wraps the expression string in a function call that converts the
// row_major matrix result of the expression to a column_major matrix.
// Base implementation uses the standard library transpose() function.
// Subclasses may override to use a different function.
string CompilerHLSL::convert_row_major_matrix(string exp_str, const SPIRType &exp_type, uint32_t /* physical_type_id */,
                                              bool /*is_packed*/, bool relaxed)
{
	strip_enclosed_expression(exp_str);
	if (!is_matrix(exp_type))
	{
		auto column_index = exp_str.find_last_of('[');
		if (column_index == string::npos)
			return exp_str;

		auto column_expr = exp_str.substr(column_index);
		exp_str.resize(column_index);

		auto transposed_expr = type_to_glsl_constructor(exp_type) + "(";

		// Loading a column from a row-major matrix. Unroll the load.
		for (uint32_t c = 0; c < exp_type.vecsize; c++)
		{
			transposed_expr += join(exp_str, '[', c, ']', column_expr);
			if (c + 1 < exp_type.vecsize)
				transposed_expr += ", ";
		}

		transposed_expr += ")";
		return transposed_expr;
	}
	else if (options.version < 120)
	{
		// GLSL 110, ES 100 do not have transpose(), so emulate it.  Note that
		// these GLSL versions do not support non-square matrices.
		if (exp_type.vecsize == 2 && exp_type.columns == 2)
			require_polyfill(PolyfillTranspose2x2, relaxed);
		else if (exp_type.vecsize == 3 && exp_type.columns == 3)
			require_polyfill(PolyfillTranspose3x3, relaxed);
		else if (exp_type.vecsize == 4 && exp_type.columns == 4)
			require_polyfill(PolyfillTranspose4x4, relaxed);
		else
			SPIRV_CROSS_THROW("Non-square matrices are not supported in legacy GLSL, cannot transpose.");
		return join("spvTranspose", (options.es && relaxed) ? "MP" : "", "(", exp_str, ")");
	}
	else
		return join("transpose(", exp_str, ")");
}

void CompilerHLSL::require_polyfill(Polyfill polyfill, bool relaxed)
{
	uint32_t &polyfills = (relaxed && options.es) ? required_polyfills_relaxed : required_polyfills;

	if ((polyfills & polyfill) == 0)
	{
		polyfills |= polyfill;
		force_recompile();
	}
}

string CompilerHLSL::load_flattened_struct(const string &basename, const SPIRType &type)
{
	auto expr = type_to_glsl_constructor(type);
	expr += '(';

	for (uint32_t i = 0; i < uint32_t(type.member_types.size()); i++)
	{
		if (i)
			expr += ", ";

		auto &member_type = get<SPIRType>(type.member_types[i]);
		if (member_type.basetype == SPIRType::Struct)
			expr += load_flattened_struct(to_flattened_struct_member(basename, type, i), member_type);
		else
			expr += to_flattened_struct_member(basename, type, i);
	}
	expr += ')';
	return expr;
}


string CompilerHLSL::to_flattened_struct_member(const string &basename, const SPIRType &type, uint32_t index)
{
	auto ret = join(basename, "_", to_member_name(type, index));
	ParsedIR::sanitize_underscores(ret);
	return ret;
}

int CompilerHLSL::get_constant_mapping_to_workgroup_component(const SPIRConstant &c) const
{
	auto &entry_point = get_entry_point();
	int index = -1;

	// Need to redirect specialization constants which are used as WorkGroupSize to the builtin,
	// since the spec constant declarations are never explicitly declared.
	if (entry_point.workgroup_size.constant == 0 && entry_point.flags.get(ExecutionModeLocalSizeId))
	{
		if (c.self == entry_point.workgroup_size.id_x)
			index = 0;
		else if (c.self == entry_point.workgroup_size.id_y)
			index = 1;
		else if (c.self == entry_point.workgroup_size.id_z)
			index = 2;
	}

	return index;
}

const char *CompilerHLSL::vector_swizzle(int vecsize, int index)
{
	static const char *const swizzle[4][4] = {
		{ ".x", ".y", ".z", ".w" },
		{ ".xy", ".yz", ".zw", nullptr },
		{ ".xyz", ".yzw", nullptr, nullptr },
#if defined(__GNUC__) && (__GNUC__ == 9)
		// This works around a GCC 9 bug, see details in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90947.
		// This array ends up being compiled as all nullptrs, tripping the assertions below.
		{ "", nullptr, nullptr, "$" },
#else
		{ "", nullptr, nullptr, nullptr },
#endif
	};

	assert(vecsize >= 1 && vecsize <= 4);
	assert(index >= 0 && index < 4);
	assert(swizzle[vecsize - 1][index]);

	return swizzle[vecsize - 1][index];
}

SmallVector<ConstantID> CompilerHLSL::get_composite_constant_ids(ConstantID const_id)
{
	if (auto *constant = maybe_get<SPIRConstant>(const_id))
	{
		const auto &type = get<SPIRType>(constant->constant_type);
		if (is_array(type) || type.basetype == SPIRType::Struct)
			return constant->subconstants;
		if (is_matrix(type))
			return SmallVector<ConstantID>(constant->m.id);
		if (is_vector(type))
			return SmallVector<ConstantID>(constant->m.c[0].id);
		SPIRV_CROSS_THROW("Unexpected scalar constant!");
	}
	if (!const_composite_insert_ids.count(const_id))
		SPIRV_CROSS_THROW("Unimplemented for this OpSpecConstantOp!");
	return const_composite_insert_ids[const_id];
}

void CompilerHLSL::set_composite_constant(ConstantID const_id, TypeID type_id,
                                          const SmallVector<ConstantID> &initializers)
{
	if (maybe_get<SPIRConstantOp>(const_id))
	{
		const_composite_insert_ids[const_id] = initializers;
		return;
	}

	auto &constant = set<SPIRConstant>(const_id, type_id);
	fill_composite_constant(constant, type_id, initializers);
	forwarded_temporaries.insert(const_id);
}

TypeID CompilerHLSL::get_composite_member_type(TypeID type_id, uint32_t member_idx)
{
	auto &type = get<SPIRType>(type_id);
	if (is_array(type))
		return type.parent_type;
	if (type.basetype == SPIRType::Struct)
		return type.member_types[member_idx];
	if (is_matrix(type))
		return type.parent_type;
	if (is_vector(type))
		return type.parent_type;
	SPIRV_CROSS_THROW("Shouldn't reach lower than vector handling OpSpecConstantOp CompositeInsert!");
}

string CompilerHLSL::bitcast_glsl(const SPIRType &result_type, uint32_t argument)
{
	auto op = bitcast_glsl_op(result_type, expression_type(argument));
	if (op.empty())
		return to_enclosed_unpacked_expression(argument);
	else
		return join(op, "(", to_unpacked_expression(argument), ")");
}

void CompilerHLSL::fill_composite_constant(SPIRConstant &constant, TypeID type_id,
                                           const SmallVector<ConstantID> &initializers)
{
	auto &type = get<SPIRType>(type_id);
	constant.specialization = true;
	if (is_array(type) || type.basetype == SPIRType::Struct)
	{
		constant.subconstants = initializers;
	}
	else if (is_matrix(type))
	{
		constant.m.columns = type.columns;
		for (uint32_t i = 0; i < type.columns; ++i)
		{
			constant.m.id[i] = initializers[i];
			constant.m.c[i].vecsize = type.vecsize;
		}
	}
	else if (is_vector(type))
	{
		constant.m.c[0].vecsize = type.vecsize;
		for (uint32_t i = 0; i < type.vecsize; ++i)
			constant.m.c[0].id[i] = initializers[i];
	}
	else
		SPIRV_CROSS_THROW("Unexpected scalar in SpecConstantOp CompositeInsert!");
}

uint32_t CompilerHLSL::get_accumulated_member_location(const SPIRVariable &var, uint32_t mbr_idx, bool strip_array) const
{
	auto &type = strip_array ? get_variable_element_type(var) : get_variable_data_type(var);
	uint32_t location = get_decoration(var.self, DecorationLocation);

	for (uint32_t i = 0; i < mbr_idx; i++)
	{
		auto &mbr_type = get<SPIRType>(type.member_types[i]);

		// Start counting from any place we have a new location decoration.
		if (has_member_decoration(type.self, mbr_idx, DecorationLocation))
			location = get_member_decoration(type.self, mbr_idx, DecorationLocation);

		uint32_t location_count = type_to_location_count(mbr_type);
		location += location_count;
	}

	return location;
}

uint32_t CompilerHLSL::type_to_location_count(const SPIRType &type) const
{
	uint32_t count;
	if (type.basetype == SPIRType::Struct)
	{
		uint32_t mbr_count = uint32_t(type.member_types.size());
		count = 0;
		for (uint32_t i = 0; i < mbr_count; i++)
			count += type_to_location_count(get<SPIRType>(type.member_types[i]));
	}
	else
	{
		count = type.columns > 1 ? type.columns : 1;
	}

	uint32_t dim_count = uint32_t(type.array.size());
	for (uint32_t i = 0; i < dim_count; i++)
		count *= to_array_size_literal(type, i);

	return count;
}

void CompilerHLSL::emit_uninitialized_temporary(uint32_t result_type, uint32_t result_id)
{
	// If we're declaring temporaries inside continue blocks,
	// we must declare the temporary in the loop header so that the continue block can avoid declaring new variables.
	if (!block_temporary_hoisting && current_continue_block && !hoisted_temporaries.count(result_id))
	{
		auto &header = get<SPIRBlock>(current_continue_block->loop_dominator);
		if (find_if(begin(header.declare_temporary), end(header.declare_temporary),
		            [result_type, result_id](const pair<uint32_t, uint32_t> &tmp) {
			            return tmp.first == result_type && tmp.second == result_id;
		            }) == end(header.declare_temporary))
		{
			header.declare_temporary.emplace_back(result_type, result_id);
			hoisted_temporaries.insert(result_id);
			force_recompile();
		}
	}
	else if (hoisted_temporaries.count(result_id) == 0)
	{
		auto &type = get<SPIRType>(result_type);
		auto &flags = get_decoration_bitset(result_id);

		// The result_id has not been made into an expression yet, so use flags interface.
		add_local_variable_name(result_id);

		string initializer;
		if (options.force_zero_initialized_variables && type_can_zero_initialize(type))
			initializer = join(" = ", to_zero_initialized_expression(result_type));

		statement(flags_to_qualifiers_glsl(type, flags), variable_decl(type, to_name(result_id)), initializer, ";");
	}
}

string CompilerHLSL::dereference_expression(const SPIRType &expr_type, const std::string &expr)
{
	// If this expression starts with an address-of operator ('&'), then
	// just return the part after the operator.
	// TODO: Strip parens if unnecessary?
	if (expr.front() == '&')
		return expr.substr(1);
	else if (backend.native_pointers)
		return join('*', expr);
	else if (expr_type.storage == StorageClassPhysicalStorageBufferEXT && expr_type.basetype != SPIRType::Struct &&
	         expr_type.pointer_depth == 1)
	{
		return join(enclose_expression(expr), ".value");
	}
	else
		return expr;
}

std::string CompilerHLSL::flattened_access_chain(uint32_t base, const uint32_t *indices, uint32_t count,
                                                 const SPIRType &target_type, uint32_t offset, uint32_t matrix_stride,
                                                 uint32_t /* array_stride */, bool need_transpose)
{
	if (!target_type.array.empty())
		SPIRV_CROSS_THROW("Access chains that result in an array can not be flattened");
	else if (target_type.basetype == SPIRType::Struct)
		return flattened_access_chain_struct(base, indices, count, target_type, offset);
	else if (target_type.columns > 1)
		return flattened_access_chain_matrix(base, indices, count, target_type, offset, matrix_stride, need_transpose);
	else
		return flattened_access_chain_vector(base, indices, count, target_type, offset, matrix_stride, need_transpose);
}

std::string CompilerHLSL::flattened_access_chain_struct(uint32_t base, const uint32_t *indices, uint32_t count,
                                                        const SPIRType &target_type, uint32_t offset)
{
	std::string expr;

	if (backend.can_declare_struct_inline)
	{
		expr += type_to_glsl_constructor(target_type);
		expr += "(";
	}
	else
		expr += "{";

	for (uint32_t i = 0; i < uint32_t(target_type.member_types.size()); ++i)
	{
		if (i != 0)
			expr += ", ";

		const SPIRType &member_type = get<SPIRType>(target_type.member_types[i]);
		uint32_t member_offset = type_struct_member_offset(target_type, i);

		// The access chain terminates at the struct, so we need to find matrix strides and row-major information
		// ahead of time.
		bool need_transpose = false;
		bool relaxed = false;
		uint32_t matrix_stride = 0;
		if (member_type.columns > 1)
		{
			auto decorations = combined_decoration_for_member(target_type, i);
			need_transpose = decorations.get(DecorationRowMajor);
			relaxed = decorations.get(DecorationRelaxedPrecision);
			matrix_stride = type_struct_member_matrix_stride(target_type, i);
		}

		auto tmp = flattened_access_chain(base, indices, count, member_type, offset + member_offset, matrix_stride,
		                                  0 /* array_stride */, need_transpose);

		// Cannot forward transpositions, so resolve them here.
		if (need_transpose)
			expr += convert_row_major_matrix(tmp, member_type, 0, false, relaxed);
		else
			expr += tmp;
	}

	expr += backend.can_declare_struct_inline ? ")" : "}";

	return expr;
}

std::string CompilerHLSL::flattened_access_chain_matrix(uint32_t base, const uint32_t *indices, uint32_t count,
                                                        const SPIRType &target_type, uint32_t offset,
                                                        uint32_t matrix_stride, bool need_transpose)
{
	assert(matrix_stride);
	SPIRType tmp_type = target_type;
	if (need_transpose)
		swap(tmp_type.vecsize, tmp_type.columns);

	std::string expr;

	expr += type_to_glsl_constructor(tmp_type);
	expr += "(";

	for (uint32_t i = 0; i < tmp_type.columns; i++)
	{
		if (i != 0)
			expr += ", ";

		expr += flattened_access_chain_vector(base, indices, count, tmp_type, offset + i * matrix_stride, matrix_stride,
		                                      /* need_transpose= */ false);
	}

	expr += ")";

	return expr;
}

std::string CompilerHLSL::flattened_access_chain_vector(uint32_t base, const uint32_t *indices, uint32_t count,
                                                        const SPIRType &target_type, uint32_t offset,
                                                        uint32_t matrix_stride, bool need_transpose)
{
	auto result = flattened_access_chain_offset(expression_type(base), indices, count, offset, 16);

	auto buffer_name = to_name(expression_type(base).self);

	if (need_transpose)
	{
		std::string expr;

		if (target_type.vecsize > 1)
		{
			expr += type_to_glsl_constructor(target_type);
			expr += "(";
		}

		for (uint32_t i = 0; i < target_type.vecsize; ++i)
		{
			if (i != 0)
				expr += ", ";

			uint32_t component_offset = result.second + i * matrix_stride;

			assert(component_offset % (target_type.width / 8) == 0);
			uint32_t index = component_offset / (target_type.width / 8);

			expr += buffer_name;
			expr += "[";
			expr += result.first; // this is a series of N1 * k1 + N2 * k2 + ... that is either empty or ends with a +
			expr += convert_to_string(index / 4);
			expr += "]";

			expr += vector_swizzle(1, index % 4);
		}

		if (target_type.vecsize > 1)
		{
			expr += ")";
		}

		return expr;
	}
	else
	{
		assert(result.second % (target_type.width / 8) == 0);
		uint32_t index = result.second / (target_type.width / 8);

		std::string expr;

		expr += buffer_name;
		expr += "[";
		expr += result.first; // this is a series of N1 * k1 + N2 * k2 + ... that is either empty or ends with a +
		expr += convert_to_string(index / 4);
		expr += "]";

		expr += vector_swizzle(target_type.vecsize, index % 4);

		return expr;
	}
}

void CompilerHLSL::request_subgroup_feature(ShaderSubgroupSupportHelper::Feature feature)
{
	if (options.vulkan_semantics)
	{
		auto khr_extension = ShaderSubgroupSupportHelper::get_KHR_extension_for_feature(feature);
		require_extension_internal(ShaderSubgroupSupportHelper::get_extension_name(khr_extension));
	}
	else
	{
		if (!shader_subgroup_supporter.is_feature_requested(feature))
			force_recompile();
		shader_subgroup_supporter.request_feature(feature);
	}
}

void CompilerHLSL::rewrite_load_for_wrapped_row_major(std::string &expr, TypeID loaded_type, ID ptr)
{
	// Loading row-major matrices from UBOs on older AMD Windows OpenGL drivers is problematic.
	// To load these types correctly, we must first wrap them in a dummy function which only purpose is to
	// ensure row_major decoration is actually respected.
	auto *var = maybe_get_backing_variable(ptr);
	if (!var)
		return;

	auto &backing_type = get<SPIRType>(var->basetype);
	bool is_ubo = backing_type.basetype == SPIRType::Struct && backing_type.storage == StorageClassUniform &&
	              has_decoration(backing_type.self, DecorationBlock);
	if (!is_ubo)
		return;

	auto *type = &get<SPIRType>(loaded_type);
	bool rewrite = false;
	bool relaxed = options.es;

	if (is_matrix(*type))
	{
		// To avoid adding a lot of unnecessary meta tracking to forward the row_major state,
		// we will simply look at the base struct itself. It is exceptionally rare to mix and match row-major/col-major state.
		// If there is any row-major action going on, we apply the workaround.
		// It is harmless to apply the workaround to column-major matrices, so this is still a valid solution.
		// If an access chain occurred, the workaround is not required, so loading vectors or scalars don't need workaround.
		type = &backing_type;
	}
	else
	{
		// If we're loading a composite, we don't have overloads like these.
		relaxed = false;
	}

	if (type->basetype == SPIRType::Struct)
	{
		// If we're loading a struct where any member is a row-major matrix, apply the workaround.
		for (uint32_t i = 0; i < uint32_t(type->member_types.size()); i++)
		{
			auto decorations = combined_decoration_for_member(*type, i);
			if (decorations.get(DecorationRowMajor))
				rewrite = true;

			// Since we decide on a per-struct basis, only use mediump wrapper if all candidates are mediump.
			if (!decorations.get(DecorationRelaxedPrecision))
				relaxed = false;
		}
	}

	if (rewrite)
	{
		request_workaround_wrapper_overload(loaded_type);
		expr = join("spvWorkaroundRowMajor", (relaxed ? "MP" : ""), "(", expr, ")");
	}
}

void CompilerHLSL::request_workaround_wrapper_overload(TypeID id)
{
	// Must be ordered to maintain deterministic output, so vector is appropriate.
	if (find(begin(workaround_ubo_load_overload_types), end(workaround_ubo_load_overload_types), id) ==
	    end(workaround_ubo_load_overload_types))
	{
		force_recompile();
		workaround_ubo_load_overload_types.push_back(id);
	}
}

void CompilerHLSL::emit_binary_func_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                            const char *op, SPIRType::BaseType input_type, bool skip_cast_if_equal_type)
{
	string cast_op0, cast_op1;
	auto expected_type = binary_op_bitcast_helper(cast_op0, cast_op1, input_type, op0, op1, skip_cast_if_equal_type);
	auto &out_type = get<SPIRType>(result_type);

	// Special case boolean outputs since relational opcodes output booleans instead of int/uint.
	string expr;
	if (out_type.basetype != input_type && out_type.basetype != SPIRType::Boolean)
	{
		expected_type.basetype = input_type;
		expr = bitcast_glsl_op(out_type, expected_type);
		expr += '(';
		expr += join(op, "(", cast_op0, ", ", cast_op1, ")");
		expr += ')';
	}
	else
	{
		expr += join(op, "(", cast_op0, ", ", cast_op1, ")");
	}

	emit_op(result_type, result_id, expr, should_forward(op0) && should_forward(op1));
	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
}

void CompilerHLSL::emit_trinary_func_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                             uint32_t op2, const char *op, SPIRType::BaseType input_type)
{
	auto &out_type = get<SPIRType>(result_type);
	auto expected_type = out_type;
	expected_type.basetype = input_type;
	string cast_op0 =
	    expression_type(op0).basetype != input_type ? bitcast_glsl(expected_type, op0) : to_unpacked_expression(op0);
	string cast_op1 =
	    expression_type(op1).basetype != input_type ? bitcast_glsl(expected_type, op1) : to_unpacked_expression(op1);
	string cast_op2 =
	    expression_type(op2).basetype != input_type ? bitcast_glsl(expected_type, op2) : to_unpacked_expression(op2);

	string expr;
	if (out_type.basetype != input_type)
	{
		expr = bitcast_glsl_op(out_type, expected_type);
		expr += '(';
		expr += join(op, "(", cast_op0, ", ", cast_op1, ", ", cast_op2, ")");
		expr += ')';
	}
	else
	{
		expr += join(op, "(", cast_op0, ", ", cast_op1, ", ", cast_op2, ")");
	}

	emit_op(result_type, result_id, expr, should_forward(op0) && should_forward(op1) && should_forward(op2));
	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
	inherit_expression_dependencies(result_id, op2);
}

void CompilerHLSL::emit_nminmax_op(uint32_t result_type, uint32_t id, uint32_t op0, uint32_t op1, GLSLstd450 op)
{
	// Need to emulate this call.
	uint32_t &ids = extra_sub_expressions[id];
	if (!ids)
	{
		ids = ir.increase_bound_by(5);
		auto btype = get<SPIRType>(result_type);
		btype.basetype = SPIRType::Boolean;
		set<SPIRType>(ids, btype);
	}

	uint32_t btype_id = ids + 0;
	uint32_t left_nan_id = ids + 1;
	uint32_t right_nan_id = ids + 2;
	uint32_t tmp_id = ids + 3;
	uint32_t mixed_first_id = ids + 4;

	// Inherit precision qualifiers.
	ir.meta[tmp_id] = ir.meta[id];
	ir.meta[mixed_first_id] = ir.meta[id];

	if (!is_legacy())
	{
		emit_unary_func_op(btype_id, left_nan_id, op0, "isnan");
		emit_unary_func_op(btype_id, right_nan_id, op1, "isnan");
	}
	else if (expression_type(op0).vecsize > 1)
	{
		// If the number doesn't equal itself, it must be NaN
		emit_binary_func_op(btype_id, left_nan_id, op0, op0, "notEqual");
		emit_binary_func_op(btype_id, right_nan_id, op1, op1, "notEqual");
	}
	else
	{
		emit_binary_op(btype_id, left_nan_id, op0, op0, "!=");
		emit_binary_op(btype_id, right_nan_id, op1, op1, "!=");
	}
	emit_binary_func_op(result_type, tmp_id, op0, op1, op == GLSLstd450NMin ? "min" : "max");
	emit_mix_op(result_type, mixed_first_id, tmp_id, op1, left_nan_id);
	emit_mix_op(result_type, id, mixed_first_id, op0, right_nan_id);
}

void CompilerHLSL::store_flattened_struct(const string &basename, uint32_t rhs_id, const SPIRType &type,
                                          const SmallVector<uint32_t> &indices)
{
	SmallVector<uint32_t> sub_indices = indices;
	sub_indices.push_back(0);

	auto *member_type = &type;
	for (auto &index : indices)
		member_type = &get<SPIRType>(member_type->member_types[index]);

	for (uint32_t i = 0; i < uint32_t(member_type->member_types.size()); i++)
	{
		sub_indices.back() = i;
		auto lhs = join(basename, "_", to_member_name(*member_type, i));
		ParsedIR::sanitize_underscores(lhs);

		if (get<SPIRType>(member_type->member_types[i]).basetype == SPIRType::Struct)
		{
			store_flattened_struct(lhs, rhs_id, type, sub_indices);
		}
		else
		{
			auto rhs = to_expression(rhs_id) + to_multi_member_reference(type, sub_indices);
			statement(lhs, " = ", rhs, ";");
		}
	}
}

void CompilerHLSL::store_flattened_struct(uint32_t lhs_id, uint32_t value)
{
	auto &type = expression_type(lhs_id);
	auto basename = to_flattened_access_chain_expression(lhs_id);
	store_flattened_struct(basename, value, type, {});
}

string CompilerHLSL::to_multi_member_reference(const SPIRType &type, const SmallVector<uint32_t> &indices)
{
	string ret;
	auto *member_type = &type;
	for (auto &index : indices)
	{
		ret += join(".", to_member_name(*member_type, index));
		member_type = &get<SPIRType>(member_type->member_types[index]);
	}
	return ret;
}

void CompilerHLSL::disallow_forwarding_in_expression_chain(const SPIRExpression &expr)
{
	// Allow trivially forwarded expressions like OpLoad or trivial shuffles,
	// these will be marked as having suppressed usage tracking.
	// Our only concern is to make sure arithmetic operations are done in similar ways.
	if (expression_is_forwarded(expr.self) && !expression_suppresses_usage_tracking(expr.self) &&
	    forced_invariant_temporaries.count(expr.self) == 0)
	{
		force_temporary_and_recompile(expr.self);
		forced_invariant_temporaries.insert(expr.self);

		for (auto &dependent : expr.expression_dependencies)
			disallow_forwarding_in_expression_chain(get<SPIRExpression>(dependent));
	}
}

string CompilerHLSL::to_rerolled_array_expression(const SPIRType &parent_type,
                                                  const string &base_expr, const SPIRType &type)
{
	bool remapped_boolean = parent_type.basetype == SPIRType::Struct &&
	                        type.basetype == SPIRType::Boolean &&
	                        backend.boolean_in_struct_remapped_type != SPIRType::Boolean;

	SPIRType tmp_type;
	if (remapped_boolean)
	{
		tmp_type = get<SPIRType>(type.parent_type);
		tmp_type.basetype = backend.boolean_in_struct_remapped_type;
	}
	else if (type.basetype == SPIRType::Boolean && backend.boolean_in_struct_remapped_type != SPIRType::Boolean)
	{
		// It's possible that we have an r-value expression that was OpLoaded from a struct.
		// We have to reroll this and explicitly cast the input to bool, because the r-value is short.
		tmp_type = get<SPIRType>(type.parent_type);
		remapped_boolean = true;
	}

	uint32_t size = to_array_size_literal(type);
	auto &parent = get<SPIRType>(type.parent_type);
	string expr = "{ ";

	for (uint32_t i = 0; i < size; i++)
	{
		auto subexpr = join(base_expr, "[", convert_to_string(i), "]");
		if (!type_is_top_level_array(parent))
		{
			if (remapped_boolean)
				subexpr = join(type_to_glsl(tmp_type), "(", subexpr, ")");
			expr += subexpr;
		}
		else
			expr += to_rerolled_array_expression(parent_type, subexpr, parent);

		if (i + 1 < size)
			expr += ", ";
	}

	expr += " }";
	return expr;
}

string CompilerHLSL::to_extract_constant_composite_expression(uint32_t result_type, const SPIRConstant &c,
                                                              const uint32_t *chain, uint32_t length)
{
	// It is kinda silly if application actually enter this path since they know the constant up front.
	// It is useful here to extract the plain constant directly.
	SPIRConstant tmp;
	tmp.constant_type = result_type;
	auto &composite_type = get<SPIRType>(c.constant_type);
	assert(composite_type.basetype != SPIRType::Struct && composite_type.array.empty());
	assert(!c.specialization);

	if (is_matrix(composite_type))
	{
		if (length == 2)
		{
			tmp.m.c[0].vecsize = 1;
			tmp.m.columns = 1;
			tmp.m.c[0].r[0] = c.m.c[chain[0]].r[chain[1]];
		}
		else
		{
			assert(length == 1);
			tmp.m.c[0].vecsize = composite_type.vecsize;
			tmp.m.columns = 1;
			tmp.m.c[0] = c.m.c[chain[0]];
		}
	}
	else
	{
		assert(length == 1);
		tmp.m.c[0].vecsize = 1;
		tmp.m.columns = 1;
		tmp.m.c[0].r[0] = c.m.c[0].r[chain[0]];
	}

	return constant_expression(tmp);
}

void CompilerHLSL::emit_copy_logical_type(uint32_t lhs_id, uint32_t lhs_type_id, uint32_t rhs_id, uint32_t rhs_type_id,
                                          SmallVector<uint32_t> chain)
{
	// Fully unroll all member/array indices one by one.

	auto &lhs_type = get<SPIRType>(lhs_type_id);
	auto &rhs_type = get<SPIRType>(rhs_type_id);

	if (!lhs_type.array.empty())
	{
		// Could use a loop here to support specialization constants, but it gets rather complicated with nested array types,
		// and this is a rather obscure opcode anyways, keep it simple unless we are forced to.
		uint32_t array_size = to_array_size_literal(lhs_type);
		chain.push_back(0);

		for (uint32_t i = 0; i < array_size; i++)
		{
			chain.back() = i;
			emit_copy_logical_type(lhs_id, lhs_type.parent_type, rhs_id, rhs_type.parent_type, chain);
		}
	}
	else if (lhs_type.basetype == SPIRType::Struct)
	{
		chain.push_back(0);
		uint32_t member_count = uint32_t(lhs_type.member_types.size());
		for (uint32_t i = 0; i < member_count; i++)
		{
			chain.back() = i;
			emit_copy_logical_type(lhs_id, lhs_type.member_types[i], rhs_id, rhs_type.member_types[i], chain);
		}
	}
	else
	{
		// Need to handle unpack/packing fixups since this can differ wildly between the logical types,
		// particularly in MSL.
		// To deal with this, we emit access chains and go through emit_store_statement
		// to deal with all the special cases we can encounter.

		AccessChainMeta lhs_meta, rhs_meta;
		auto lhs = access_chain_internal(lhs_id, chain.data(), uint32_t(chain.size()),
		                                 ACCESS_CHAIN_INDEX_IS_LITERAL_BIT, &lhs_meta);
		auto rhs = access_chain_internal(rhs_id, chain.data(), uint32_t(chain.size()),
		                                 ACCESS_CHAIN_INDEX_IS_LITERAL_BIT, &rhs_meta);

		uint32_t id = ir.increase_bound_by(2);
		lhs_id = id;
		rhs_id = id + 1;

		{
			auto &lhs_expr = set<SPIRExpression>(lhs_id, std::move(lhs), lhs_type_id, true);
			lhs_expr.need_transpose = lhs_meta.need_transpose;

			if (lhs_meta.storage_is_packed)
				set_extended_decoration(lhs_id, SPIRVCrossDecorationPhysicalTypePacked);
			if (lhs_meta.storage_physical_type != 0)
				set_extended_decoration(lhs_id, SPIRVCrossDecorationPhysicalTypeID, lhs_meta.storage_physical_type);

			forwarded_temporaries.insert(lhs_id);
			suppressed_usage_tracking.insert(lhs_id);
		}

		{
			auto &rhs_expr = set<SPIRExpression>(rhs_id, std::move(rhs), rhs_type_id, true);
			rhs_expr.need_transpose = rhs_meta.need_transpose;

			if (rhs_meta.storage_is_packed)
				set_extended_decoration(rhs_id, SPIRVCrossDecorationPhysicalTypePacked);
			if (rhs_meta.storage_physical_type != 0)
				set_extended_decoration(rhs_id, SPIRVCrossDecorationPhysicalTypeID, rhs_meta.storage_physical_type);

			forwarded_temporaries.insert(rhs_id);
			suppressed_usage_tracking.insert(rhs_id);
		}

		emit_store_statement(lhs_id, rhs_id);
	}
}

// Used explicitly when we want to read a row-major expression, but without any transpose shenanigans.
// need_transpose must be forced to false.
string CompilerHLSL::to_unpacked_row_major_matrix_expression(uint32_t id)
{
	return unpack_expression_type(to_expression(id), expression_type(id),
	                              get_extended_decoration(id, SPIRVCrossDecorationPhysicalTypeID),
	                              has_extended_decoration(id, SPIRVCrossDecorationPhysicalTypePacked), true);
}

void CompilerHLSL::emit_unary_op_cast(uint32_t result_type, uint32_t result_id, uint32_t op0, const char *op)
{
	auto &type = get<SPIRType>(result_type);
	bool forward = should_forward(op0);
	emit_op(result_type, result_id, join(type_to_glsl(type), "(", op, to_enclosed_unpacked_expression(op0), ")"), forward);
	inherit_expression_dependencies(result_id, op0);
}

void CompilerHLSL::emit_bitfield_insert_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                           uint32_t op2, uint32_t op3, const char *op,
                                           SPIRType::BaseType offset_count_type)
{
	// Only need to cast offset/count arguments. Types of base/insert must be same as result type,
	// and bitfieldInsert is sign invariant.
	bool forward = should_forward(op0) && should_forward(op1) && should_forward(op2) && should_forward(op3);

	auto op0_expr = to_unpacked_expression(op0);
	auto op1_expr = to_unpacked_expression(op1);
	auto op2_expr = to_unpacked_expression(op2);
	auto op3_expr = to_unpacked_expression(op3);

	SPIRType target_type;
	target_type.vecsize = 1;
	target_type.basetype = offset_count_type;

	if (expression_type(op2).basetype != offset_count_type)
	{
		// Value-cast here. Input might be 16-bit. GLSL requires int.
		op2_expr = join(type_to_glsl_constructor(target_type), "(", op2_expr, ")");
	}

	if (expression_type(op3).basetype != offset_count_type)
	{
		// Value-cast here. Input might be 16-bit. GLSL requires int.
		op3_expr = join(type_to_glsl_constructor(target_type), "(", op3_expr, ")");
	}

	emit_op(result_type, result_id, join(op, "(", op0_expr, ", ", op1_expr, ", ", op2_expr, ", ", op3_expr, ")"),
	        forward);

	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
	inherit_expression_dependencies(result_id, op2);
	inherit_expression_dependencies(result_id, op3);
}

// Very special case. Handling bitfieldExtract requires us to deal with different bitcasts of different signs
// and different vector sizes all at once. Need a special purpose method here.
void CompilerHLSL::emit_trinary_func_op_bitextract(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                                   uint32_t op2, const char *op,
                                                   SPIRType::BaseType expected_result_type,
                                                   SPIRType::BaseType input_type0, SPIRType::BaseType input_type1,
                                                   SPIRType::BaseType input_type2)
{
	auto &out_type = get<SPIRType>(result_type);
	auto expected_type = out_type;
	expected_type.basetype = input_type0;

	string cast_op0 =
	    expression_type(op0).basetype != input_type0 ? bitcast_glsl(expected_type, op0) : to_unpacked_expression(op0);

	auto op1_expr = to_unpacked_expression(op1);
	auto op2_expr = to_unpacked_expression(op2);

	// Use value casts here instead. Input must be exactly int or uint, but SPIR-V might be 16-bit.
	expected_type.basetype = input_type1;
	expected_type.vecsize = 1;
	string cast_op1 = expression_type(op1).basetype != input_type1 ?
	                      join(type_to_glsl_constructor(expected_type), "(", op1_expr, ")") :
	                      op1_expr;

	expected_type.basetype = input_type2;
	expected_type.vecsize = 1;
	string cast_op2 = expression_type(op2).basetype != input_type2 ?
	                      join(type_to_glsl_constructor(expected_type), "(", op2_expr, ")") :
	                      op2_expr;

	string expr;
	if (out_type.basetype != expected_result_type)
	{
		expected_type.vecsize = out_type.vecsize;
		expected_type.basetype = expected_result_type;
		expr = bitcast_glsl_op(out_type, expected_type);
		expr += '(';
		expr += join(op, "(", cast_op0, ", ", cast_op1, ", ", cast_op2, ")");
		expr += ')';
	}
	else
	{
		expr += join(op, "(", cast_op0, ", ", cast_op1, ", ", cast_op2, ")");
	}

	emit_op(result_type, result_id, expr, should_forward(op0) && should_forward(op1) && should_forward(op2));
	inherit_expression_dependencies(result_id, op0);
	inherit_expression_dependencies(result_id, op1);
	inherit_expression_dependencies(result_id, op2);
}

bool CompilerHLSL::check_atomic_image(uint32_t id)
{
	auto &type = expression_type(id);
	if (type.storage == StorageClassImage)
	{
		if (options.es && options.version < 320)
			require_extension_internal("GL_OES_shader_image_atomic");

		auto *var = maybe_get_backing_variable(id);
		if (var)
		{
			if (has_decoration(var->self, DecorationNonWritable) || has_decoration(var->self, DecorationNonReadable))
			{
				unset_decoration(var->self, DecorationNonWritable);
				unset_decoration(var->self, DecorationNonReadable);
				force_recompile();
			}
		}
		return true;
	}
	else
		return false;
}

void CompilerHLSL::emit_atomic_func_op(uint32_t result_type, uint32_t result_id, uint32_t op0, uint32_t op1,
                                       const char *op)
{
	auto &type = get<SPIRType>(result_type);
	if (type_is_floating_point(type))
	{
		if (!options.vulkan_semantics)
			SPIRV_CROSS_THROW("Floating point atomics requires Vulkan semantics.");
		if (options.es)
			SPIRV_CROSS_THROW("Floating point atomics requires desktop GLSL.");
		require_extension_internal("GL_EXT_shader_atomic_float");
	}

	forced_temporaries.insert(result_id);
	emit_op(result_type, result_id,
	        join(op, "(", to_non_uniform_aware_expression(op0), ", ",
	             to_unpacked_expression(op1), ")"), false);
	flush_all_atomic_capable_variables();
}

void CompilerHLSL::emit_atomic_func_op(uint32_t result_type, uint32_t result_id,
                                       uint32_t op0, uint32_t op1, uint32_t op2,
                                       const char *op)
{
	forced_temporaries.insert(result_id);
	emit_op(result_type, result_id,
	        join(op, "(", to_non_uniform_aware_expression(op0), ", ",
	             to_unpacked_expression(op1), ", ", to_unpacked_expression(op2), ")"), false);
	flush_all_atomic_capable_variables();
}

std::string CompilerHLSL::convert_separate_image_to_expression(uint32_t id)
{
	auto *var = maybe_get_backing_variable(id);

	// If we are fetching from a plain OpTypeImage, we must combine with a dummy sampler in GLSL.
	// In Vulkan GLSL, we can make use of the newer GL_EXT_samplerless_texture_functions.
	if (var)
	{
		auto &type = get<SPIRType>(var->basetype);
		if (type.basetype == SPIRType::Image && type.image.sampled == 1 && type.image.dim != DimBuffer)
		{
			if (options.vulkan_semantics)
			{
				if (dummy_sampler_id)
				{
					// Don't need to consider Shadow state since the dummy sampler is always non-shadow.
					auto sampled_type = type;
					sampled_type.basetype = SPIRType::SampledImage;
					return join(type_to_glsl(sampled_type), "(", to_non_uniform_aware_expression(id), ", ",
					            to_expression(dummy_sampler_id), ")");
				}
				else
				{
					// Newer glslang supports this extension to deal with texture2D as argument to texture functions.
					require_extension_internal("GL_EXT_samplerless_texture_functions");
				}
			}
			else
			{
				if (!dummy_sampler_id)
					SPIRV_CROSS_THROW("Cannot find dummy sampler ID. Was "
					                  "build_dummy_sampler_for_combined_images() called?");

				return to_combined_image_sampler(id, dummy_sampler_id);
			}
		}
	}

	return to_non_uniform_aware_expression(id);
}

string CompilerHLSL::legacy_tex_op(const std::string &op, const SPIRType &imgtype, uint32_t tex)
{
	const char *type;
	switch (imgtype.image.dim)
	{
	case spv::Dim1D:
		// Force 2D path for ES.
		if (options.es)
			type = (imgtype.image.arrayed && !options.es) ? "2DArray" : "2D";
		else
			type = (imgtype.image.arrayed && !options.es) ? "1DArray" : "1D";
		break;
	case spv::Dim2D:
		type = (imgtype.image.arrayed && !options.es) ? "2DArray" : "2D";
		break;
	case spv::Dim3D:
		type = "3D";
		break;
	case spv::DimCube:
		type = "Cube";
		break;
	case spv::DimRect:
		type = "2DRect";
		break;
	case spv::DimBuffer:
		type = "Buffer";
		break;
	case spv::DimSubpassData:
		type = "2D";
		break;
	default:
		type = "";
		break;
	}

	// In legacy GLSL, an extension is required for textureLod in the fragment
	// shader or textureGrad anywhere.
	bool legacy_lod_ext = false;
	auto &execution = get_entry_point();
	if (op == "textureGrad" || op == "textureProjGrad" ||
	    ((op == "textureLod" || op == "textureProjLod") && execution.model != ExecutionModelVertex))
	{
		if (is_legacy_es())
		{
			legacy_lod_ext = true;
			require_extension_internal("GL_EXT_shader_texture_lod");
		}
		else if (is_legacy_desktop())
			require_extension_internal("GL_ARB_shader_texture_lod");
	}

	if (op == "textureLodOffset" || op == "textureProjLodOffset")
	{
		if (is_legacy_es())
			SPIRV_CROSS_THROW(join(op, " not allowed in legacy ES"));

		require_extension_internal("GL_EXT_gpu_shader4");
	}

	// GLES has very limited support for shadow samplers.
	// Basically shadow2D and shadow2DProj work through EXT_shadow_samplers,
	// everything else can just throw
	bool is_comparison = is_depth_image(imgtype, tex);
	if (is_comparison && is_legacy_es())
	{
		if (op == "texture" || op == "textureProj")
			require_extension_internal("GL_EXT_shadow_samplers");
		else
			SPIRV_CROSS_THROW(join(op, " not allowed on depth samplers in legacy ES"));

		if (imgtype.image.dim == spv::DimCube)
			return "shadowCubeNV";
	}

	if (op == "textureSize")
	{
		if (is_legacy_es())
			SPIRV_CROSS_THROW("textureSize not supported in legacy ES");
		if (is_comparison)
			SPIRV_CROSS_THROW("textureSize not supported on shadow sampler in legacy GLSL");
		require_extension_internal("GL_EXT_gpu_shader4");
	}

	if (op == "texelFetch" && is_legacy_es())
		SPIRV_CROSS_THROW("texelFetch not supported in legacy ES");

	bool is_es_and_depth = is_legacy_es() && is_comparison;
	std::string type_prefix = is_comparison ? "shadow" : "texture";

	if (op == "texture")
		return is_es_and_depth ? join(type_prefix, type, "EXT") : join(type_prefix, type);
	else if (op == "textureLod")
		return join(type_prefix, type, legacy_lod_ext ? "LodEXT" : "Lod");
	else if (op == "textureProj")
		return join(type_prefix, type, is_es_and_depth ? "ProjEXT" : "Proj");
	else if (op == "textureGrad")
		return join(type_prefix, type, is_legacy_es() ? "GradEXT" : is_legacy_desktop() ? "GradARB" : "Grad");
	else if (op == "textureProjLod")
		return join(type_prefix, type, legacy_lod_ext ? "ProjLodEXT" : "ProjLod");
	else if (op == "textureLodOffset")
		return join(type_prefix, type, "LodOffset");
	else if (op == "textureProjGrad")
		return join(type_prefix, type,
		            is_legacy_es() ? "ProjGradEXT" : is_legacy_desktop() ? "ProjGradARB" : "ProjGrad");
	else if (op == "textureProjLodOffset")
		return join(type_prefix, type, "ProjLodOffset");
	else if (op == "textureSize")
		return join("textureSize", type);
	else if (op == "texelFetch")
		return join("texelFetch", type);
	else
	{
		SPIRV_CROSS_THROW(join("Unsupported legacy texture op: ", op));
	}
}

bool CompilerHLSL::subpass_input_is_framebuffer_fetch(uint32_t id) const
{
	if (!has_decoration(id, DecorationInputAttachmentIndex))
		return false;

	uint32_t input_attachment_index = get_decoration(id, DecorationInputAttachmentIndex);
	for (auto &remap : subpass_to_framebuffer_fetch_attachment)
		if (remap.first == input_attachment_index)
			return true;

	return false;
}

void CompilerHLSL::emit_sparse_feedback_temporaries(uint32_t result_type_id, uint32_t id, uint32_t &feedback_id,
                                                    uint32_t &texel_id)
{
	// Need to allocate two temporaries.
	if (options.es)
		SPIRV_CROSS_THROW("Sparse texture feedback is not supported on ESSL.");
	require_extension_internal("GL_ARB_sparse_texture2");

	auto &temps = extra_sub_expressions[id];
	if (temps == 0)
		temps = ir.increase_bound_by(2);

	feedback_id = temps + 0;
	texel_id = temps + 1;

	auto &return_type = get<SPIRType>(result_type_id);
	if (return_type.basetype != SPIRType::Struct || return_type.member_types.size() != 2)
		SPIRV_CROSS_THROW("Invalid return type for sparse feedback.");
	emit_uninitialized_temporary(return_type.member_types[0], feedback_id);
	emit_uninitialized_temporary(return_type.member_types[1], texel_id);
}

void CompilerHLSL::emit_spv_amd_shader_ballot_op(uint32_t result_type, uint32_t id, uint32_t eop, const uint32_t *args,
                                                 uint32_t)
{
	require_extension_internal("GL_AMD_shader_ballot");

	enum AMDShaderBallot
	{
		SwizzleInvocationsAMD = 1,
		SwizzleInvocationsMaskedAMD = 2,
		WriteInvocationAMD = 3,
		MbcntAMD = 4
	};

	auto op = static_cast<AMDShaderBallot>(eop);

	switch (op)
	{
	case SwizzleInvocationsAMD:
		emit_binary_func_op(result_type, id, args[0], args[1], "swizzleInvocationsAMD");
		register_control_dependent_expression(id);
		break;

	case SwizzleInvocationsMaskedAMD:
		emit_binary_func_op(result_type, id, args[0], args[1], "swizzleInvocationsMaskedAMD");
		register_control_dependent_expression(id);
		break;

	case WriteInvocationAMD:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "writeInvocationAMD");
		register_control_dependent_expression(id);
		break;

	case MbcntAMD:
		emit_unary_func_op(result_type, id, args[0], "mbcntAMD");
		register_control_dependent_expression(id);
		break;

	default:
		statement("// unimplemented SPV AMD shader ballot op ", eop);
		break;
	}
}

void CompilerHLSL::emit_spv_amd_shader_explicit_vertex_parameter_op(uint32_t result_type, uint32_t id, uint32_t eop,
                                                                    const uint32_t *args, uint32_t)
{
	require_extension_internal("GL_AMD_shader_explicit_vertex_parameter");

	enum AMDShaderExplicitVertexParameter
	{
		InterpolateAtVertexAMD = 1
	};

	auto op = static_cast<AMDShaderExplicitVertexParameter>(eop);

	switch (op)
	{
	case InterpolateAtVertexAMD:
		emit_binary_func_op(result_type, id, args[0], args[1], "interpolateAtVertexAMD");
		break;

	default:
		statement("// unimplemented SPV AMD shader explicit vertex parameter op ", eop);
		break;
	}
}

void CompilerHLSL::emit_spv_amd_shader_trinary_minmax_op(uint32_t result_type, uint32_t id, uint32_t eop,
                                                         const uint32_t *args, uint32_t)
{
	require_extension_internal("GL_AMD_shader_trinary_minmax");

	enum AMDShaderTrinaryMinMax
	{
		FMin3AMD = 1,
		UMin3AMD = 2,
		SMin3AMD = 3,
		FMax3AMD = 4,
		UMax3AMD = 5,
		SMax3AMD = 6,
		FMid3AMD = 7,
		UMid3AMD = 8,
		SMid3AMD = 9
	};

	auto op = static_cast<AMDShaderTrinaryMinMax>(eop);

	switch (op)
	{
	case FMin3AMD:
	case UMin3AMD:
	case SMin3AMD:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "min3");
		break;

	case FMax3AMD:
	case UMax3AMD:
	case SMax3AMD:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "max3");
		break;

	case FMid3AMD:
	case UMid3AMD:
	case SMid3AMD:
		emit_trinary_func_op(result_type, id, args[0], args[1], args[2], "mid3");
		break;

	default:
		statement("// unimplemented SPV AMD shader trinary minmax op ", eop);
		break;
	}
}

void CompilerHLSL::emit_spv_amd_gcn_shader_op(uint32_t result_type, uint32_t id, uint32_t eop, const uint32_t *args,
                                              uint32_t)
{
	require_extension_internal("GL_AMD_gcn_shader");

	enum AMDGCNShader
	{
		CubeFaceIndexAMD = 1,
		CubeFaceCoordAMD = 2,
		TimeAMD = 3
	};

	auto op = static_cast<AMDGCNShader>(eop);

	switch (op)
	{
	case CubeFaceIndexAMD:
		emit_unary_func_op(result_type, id, args[0], "cubeFaceIndexAMD");
		break;
	case CubeFaceCoordAMD:
		emit_unary_func_op(result_type, id, args[0], "cubeFaceCoordAMD");
		break;
	case TimeAMD:
	{
		string expr = "timeAMD()";
		emit_op(result_type, id, expr, true);
		register_control_dependent_expression(id);
		break;
	}

	default:
		statement("// unimplemented SPV AMD gcn shader op ", eop);
		break;
	}
}
#else
CompilerHLSL::ShaderSubgroupSupportHelper::Result::Result()
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::image_type_hlsl_legacy(const SPIRType &, uint32_t /*id*/)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::image_type_hlsl(const SPIRType &, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::to_initializer_expression(const SPIRVariable &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_interface_block_member_in_struct(const SPIRVariable &, uint32_t ,
                                                         uint32_t ,
                                                         std::unordered_set<uint32_t> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::set_hlsl_aux_buffer_binding(HLSLAuxBinding, uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::unset_hlsl_aux_buffer_binding(HLSLAuxBinding)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::is_hlsl_aux_buffer_binding_used(HLSLAuxBinding) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::analyze_meshlet_writes()
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::analyze_meshlet_writes(uint32_t, uint32_t, uint32_t,
                                          std::unordered_set<uint32_t> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_rayquery_function(const char *, const char *, const uint32_t *)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_mesh_tasks(SPIRBlock &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_push_constant_block(const SPIRVariable &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_legacy_uniform(const SPIRVariable &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::bitcast_glsl_op(const SPIRType &, const SPIRType &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::read_access_chain_array(const string &, const SPIRAccessChain &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::read_access_chain_struct(const string &, const SPIRAccessChain &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::read_access_chain(string *, const string &, const SPIRAccessChain &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::write_access_chain_array(const SPIRAccessChain &, uint32_t,
                                            const SmallVector<uint32_t> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::write_access_chain_struct(const SPIRAccessChain &, uint32_t,
                                             const SmallVector<uint32_t> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::write_access_chain_value(uint32_t, const SmallVector<uint32_t> &,
                                              bool)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::write_access_chain(const SPIRAccessChain &, uint32_t ,
                                      const SmallVector<uint32_t> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_atomic(const uint32_t *, uint32_t , spv::Op )
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_subgroup_op(const Instruction &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::require_texture_query_variant(uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

VariableID CompilerHLSL::remap_num_workgroups_builtin()
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::set_resource_binding_flags(HLSLBindingFlags)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::get_unique_identifier()
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::add_hlsl_resource_binding(const HLSLResourceBinding &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::is_hlsl_resource_binding_used(ExecutionModel, uint32_t, uint32_t) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

CompilerHLSL::BitcastType CompilerHLSL::get_bitcast_type(uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::is_hlsl_force_storage_buffer_as_uav(ID) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::set_hlsl_force_storage_buffer_as_uav(uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::constant_op_expression(const SPIRConstantOp &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::type_can_zero_initialize(const SPIRType &) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::to_zero_initialized_expression(uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::fixup_implicit_builtin_block_names(ExecutionModel)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

uint32_t CompilerHLSL::get_declared_member_location(const SPIRVariable &, uint32_t, bool) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_buffer_block_flattened(const SPIRVariable &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::to_combined_image_sampler(VariableID , VariableID)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::to_extract_component_expression(uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_emulated_ahyper_op(uint32_t, uint32_t, uint32_t, GLSLstd450)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::convert_non_uniform_expression(string &, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

SPIRExpression &CompilerHLSL::emit_uninitialized_temporary_expression(uint32_t type, uint32_t id)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::pair<std::string, uint32_t> CompilerHLSL::flattened_access_chain_offset(
    const SPIRType &, const uint32_t *, uint32_t , uint32_t , uint32_t ,
    bool *, uint32_t *, uint32_t *, bool )
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::bitcast_expression(SPIRType::BaseType, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::bitcast_expression(const SPIRType &, SPIRType::BaseType,
                                             const std::string &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_unrolled_unary_op(uint32_t, uint32_t, uint32_t, const char *)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_unrolled_binary_op(uint32_t, uint32_t, uint32_t, uint32_t,
                                           const char *, bool, SPIRType::BaseType)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

uint32_t CompilerHLSL::mask_relevant_memory_semantics(uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

const Instruction *CompilerHLSL::get_next_instruction_in_block(const Instruction &instr)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_line_directive(uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_while_loop_initializers(const SPIRBlock &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::address_of_expression(const std::string &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::emit_array_copy(const char *, uint32_t , uint32_t , StorageClass, StorageClass)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::analyze_precision_requirements(uint32_t, uint32_t, uint32_t *, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

CompilerHLSL::OptionsGLSL::Precision CompilerHLSL::analyze_expression_precision(const uint32_t *, uint32_t) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

uint32_t CompilerHLSL::consume_temporary_in_precision_context(uint32_t type_id, uint32_t id, OptionsGLSL::Precision precision)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::forward_relaxed_precision(uint32_t, const uint32_t *, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::convert_half_to_string(const SPIRConstant &, uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::convert_double_to_string(const SPIRConstant &, uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::require_extension_internal(const string &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::has_extension(const std::string &) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

// Wraps the expression string in a function call that converts the
// row_major matrix result of the expression to a column_major matrix.
// Base implementation uses the standard library transpose() function.
// Subclasses may override to use a different function.
string CompilerHLSL::convert_row_major_matrix(string, const SPIRType &, uint32_t /* physical_type_id */,
                                              bool /*is_packed*/, bool)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::require_polyfill(Polyfill, bool)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::load_flattened_struct(const string &, const SPIRType &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}


string CompilerHLSL::to_flattened_struct_member(const string &, const SPIRType &, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

int CompilerHLSL::get_constant_mapping_to_workgroup_component(const SPIRConstant &) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

const char *CompilerHLSL::vector_swizzle(int vecsize, int index)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

SmallVector<ConstantID> CompilerHLSL::get_composite_constant_ids(ConstantID)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::set_composite_constant(ConstantID, TypeID,
                                          const SmallVector<ConstantID> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

TypeID CompilerHLSL::get_composite_member_type(TypeID, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::bitcast_glsl(const SPIRType &, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::fill_composite_constant(SPIRConstant &, TypeID ,
                                           const SmallVector<ConstantID> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

uint32_t CompilerHLSL::get_accumulated_member_location(const SPIRVariable &, uint32_t, bool) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

uint32_t CompilerHLSL::type_to_location_count(const SPIRType &) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_uninitialized_temporary(uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::dereference_expression(const SPIRType &, const std::string &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::flattened_access_chain(uint32_t, const uint32_t *, uint32_t,
                                                 const SPIRType &, uint32_t, uint32_t,
                                                 uint32_t /* array_stride */, bool)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::flattened_access_chain_struct(uint32_t, const uint32_t *, uint32_t,
                                                        const SPIRType &, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::flattened_access_chain_matrix(uint32_t, const uint32_t *, uint32_t,
                                                        const SPIRType &, uint32_t,
                                                        uint32_t, bool)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::flattened_access_chain_vector(uint32_t, const uint32_t *, uint32_t,
                                                        const SPIRType &, uint32_t,
                                                        uint32_t, bool)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::request_subgroup_feature(ShaderSubgroupSupportHelper::Feature)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::rewrite_load_for_wrapped_row_major(std::string &, TypeID, ID)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::request_workaround_wrapper_overload(TypeID)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_binary_func_op_cast(uint32_t, uint32_t, uint32_t, uint32_t,
                                            const char *, SPIRType::BaseType, bool)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_trinary_func_op_cast(uint32_t, uint32_t, uint32_t, uint32_t,
                                             uint32_t, const char *, SPIRType::BaseType)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_nminmax_op(uint32_t, uint32_t, uint32_t, uint32_t, GLSLstd450)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::store_flattened_struct(const string &, uint32_t, const SPIRType &,
                                          const SmallVector<uint32_t> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::store_flattened_struct(uint32_t, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::to_multi_member_reference(const SPIRType &, const SmallVector<uint32_t> &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::disallow_forwarding_in_expression_chain(const SPIRExpression &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::to_rerolled_array_expression(const SPIRType &,
                                                  const string &, const SPIRType &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::to_extract_constant_composite_expression(uint32_t, const SPIRConstant &,
                                                              const uint32_t *, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_copy_logical_type(uint32_t, uint32_t, uint32_t, uint32_t,
                                          SmallVector<uint32_t>)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

// Used explicitly when we want to read a row-major expression, but without any transpose shenanigans.
// need_transpose must be forced to false.
string CompilerHLSL::to_unpacked_row_major_matrix_expression(uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_unary_op_cast(uint32_t, uint32_t, uint32_t, const char *)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_bitfield_insert_op(uint32_t, uint32_t, uint32_t, uint32_t,
                                           uint32_t, uint32_t, const char *,
                                           SPIRType::BaseType)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

// Very special case. Handling bitfieldExtract requires us to deal with different bitcasts of different signs
// and different vector sizes all at once. Need a special purpose method here.
void CompilerHLSL::emit_trinary_func_op_bitextract(uint32_t, uint32_t, uint32_t, uint32_t,
                                                   uint32_t, const char *,
                                                   SPIRType::BaseType,
                                                   SPIRType::BaseType, SPIRType::BaseType,
                                                   SPIRType::BaseType)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::check_atomic_image(uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_atomic_func_op(uint32_t, uint32_t, uint32_t, uint32_t,
                                       const char *)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_atomic_func_op(uint32_t, uint32_t,
                                       uint32_t, uint32_t, uint32_t,
                                       const char *)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

std::string CompilerHLSL::convert_separate_image_to_expression(uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

string CompilerHLSL::legacy_tex_op(const std::string &, const SPIRType &, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

bool CompilerHLSL::subpass_input_is_framebuffer_fetch(uint32_t) const
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_sparse_feedback_temporaries(uint32_t, uint32_t, uint32_t &,
                                                    uint32_t &)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_spv_amd_shader_ballot_op(uint32_t, uint32_t, uint32_t, const uint32_t *,
                                                 uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_spv_amd_shader_explicit_vertex_parameter_op(uint32_t, uint32_t, uint32_t,
                                                                    const uint32_t *, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_spv_amd_shader_trinary_minmax_op(uint32_t, uint32_t, uint32_t ,
                                                         const uint32_t *, uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}

void CompilerHLSL::emit_spv_amd_gcn_shader_op(uint32_t, uint32_t, uint32_t, const uint32_t *,
                                              uint32_t)
{
	SPIRV_CROSS_INVALID_CALL();
	SPIRV_CROSS_THROW("Invalid call.");
}
#endif