[llvm-context,solidity] Generate debug-info location information.

When debug-info generation is enabled, construct a DebugInfo instance.

Add a namespace stack to the DebugInfo structure to keep track of the
names of named scopes, such as namespaces, objects and functions,
enclosing a construct.

Generate source level debug information for the functions defined when
YUL is lowered to LLVM-IR. This includes the deploy_code and runtime
functions generated by the compiler.

Generate debug-location information for other constructs that may appear
in a contract.

crates/llvm-context/src/lib.rs

@@ -16,6 +16,7 @@ pub use self::polkavm::context::argument::Argument as PolkaVMArgument;
 pub use self::polkavm::context::attribute::Attribute as PolkaVMAttribute;
 pub use self::polkavm::context::build::Build as PolkaVMBuild;
 pub use self::polkavm::context::code_type::CodeType as PolkaVMCodeType;
+pub use self::polkavm::context::debug_info::DebugInfo;
 pub use self::polkavm::context::evmla_data::EVMLAData as PolkaVMContextEVMLAData;
 pub use self::polkavm::context::function::block::evmla_data::key::Key as PolkaVMFunctionBlockKey;
 pub use self::polkavm::context::function::block::evmla_data::EVMLAData as PolkaVMFunctionBlockEVMLAData;

crates/llvm-context/src/polkavm/context/debug_info.rs

@@ -1,14 +1,53 @@
 //! The LLVM debug information.
 
+use std::cell::RefCell;
+
 use inkwell::debug_info::AsDIScope;
-use num::Zero;
+use inkwell::debug_info::DIScope;
+
+/// Debug info scope stack
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct ScopeStack<'ctx> {
+    stack: Vec<DIScope<'ctx>>,
+}
+
+// Abstract the type of the DIScope stack.
+impl<'ctx> ScopeStack<'ctx> {
+    pub fn from(item: DIScope<'ctx>) -> Self {
+        Self { stack: vec![item] }
+    }
+
+    /// Return the top of the scope stack, or None if the stack is empty.
+    pub fn top(&self) -> Option<DIScope<'ctx>> {
+        self.stack.last().map(|rc| rc.clone())
+    }
+
+    /// Push a scope onto the stack.
+    pub fn push(&mut self, scope: DIScope<'ctx>) -> () {
+        self.stack.push(scope)
+    }
+
+    /// Pop the scope at the top of the stack and return it.
+    /// Return None if the stack is empty.
+    pub fn pop(&mut self) -> Option<DIScope<'ctx>> {
+        self.stack.pop()
+    }
+
+    pub fn len(&self) -> usize {
+        self.stack.len()
+    }
+}
 
 /// The LLVM debug information.
 pub struct DebugInfo<'ctx> {
     /// The compile unit.
     compile_unit: inkwell::debug_info::DICompileUnit<'ctx>,
     /// The debug info builder.
     builder: inkwell::debug_info::DebugInfoBuilder<'ctx>,
+    /// The debug info scope stack. Used when lowering to llvm-ir.
+    scope_stack: RefCell<ScopeStack<'ctx>>,
+    // Stack of names of enclosing objects, functions and other namespaces.
+    namespace_stack: RefCell<Vec<String>>,
 }
 
 impl<'ctx> DebugInfo<'ctx> {
@@ -35,63 +74,127 @@ impl<'ctx> DebugInfo<'ctx> {
         Self {
             compile_unit,
             builder,
+            scope_stack: RefCell::new(ScopeStack::from(compile_unit.as_debug_info_scope())),
+            namespace_stack: RefCell::new(vec![]),
         }
     }
 
-    /// Creates a function info.
+    /// Create debug-info for a function.
     pub fn create_function(
         &self,
+        scope: inkwell::debug_info::DIScope<'ctx>,
         name: &str,
+        linkage_name: Option<&str>,
+        return_type: Option<inkwell::debug_info::DIType<'ctx>>,
+        parameter_types: &[inkwell::debug_info::DIType<'ctx>],
+        file: inkwell::debug_info::DIFile<'ctx>,
+        line_num: u32,
+        is_definition: bool,
+        is_local: bool,
+        is_optimized: bool,
+        flags: Option<inkwell::debug_info::DIFlags>,
     ) -> anyhow::Result<inkwell::debug_info::DISubprogram<'ctx>> {
-        let subroutine_type = self.builder.create_subroutine_type(
-            self.compile_unit.get_file(),
-            Some(self.create_type(revive_common::BIT_LENGTH_FIELD)?),
-            &[],
-            inkwell::debug_info::DIFlags::zero(),
-        );
+        let di_flags = flags.unwrap_or(inkwell::debug_info::DIFlagsConstants::ZERO);
+        let ret_type = return_type.unwrap_or(self.create_word_type(flags)?.as_type());
+        let subroutine_type =
+            self.builder
+                .create_subroutine_type(file, Some(ret_type), parameter_types, di_flags);
 
         let function = self.builder.create_function(
-            self.compile_unit.get_file().as_debug_info_scope(),
+            scope,
             name,
-            None,
-            self.compile_unit.get_file(),
-            42,
+            linkage_name,
+            file,
+            line_num,
             subroutine_type,
-            true,
-            false,
-            1,
-            inkwell::debug_info::DIFlags::zero(),
-            false,
-        );
-
-        self.builder.create_lexical_block(
-            function.as_debug_info_scope(),
-            self.compile_unit.get_file(),
-            1,
+            is_local,
+            is_definition,
             1,
+            di_flags,
+            is_optimized,
         );
 
         Ok(function)
     }
 
-    /// Creates a primitive type info.
-    pub fn create_type(
+    /// Creates primitive integer type debug-info.
+    pub fn create_primitive_type(
         &self,
         bit_length: usize,
-    ) -> anyhow::Result<inkwell::debug_info::DIType<'ctx>> {
+        flags: Option<inkwell::debug_info::DIFlags>,
+    ) -> anyhow::Result<inkwell::debug_info::DIBasicType<'ctx>> {
+        let di_flags = flags.unwrap_or(inkwell::debug_info::DIFlagsConstants::ZERO);
+        let di_encoding: u32 = 0;
+        let type_name = String::from("U") + bit_length.to_string().as_str();
         self.builder
-            .create_basic_type(
-                "U256",
-                bit_length as u64,
-                0,
-                inkwell::debug_info::DIFlags::zero(),
-            )
-            .map(|basic_type| basic_type.as_type())
+            .create_basic_type(type_name.as_str(), bit_length as u64, di_encoding, di_flags)
             .map_err(|error| anyhow::anyhow!("Debug info error: {}", error))
     }
 
-    /// Finalizes the builder.
-    pub fn finalize(&self) {
-        self.builder.finalize();
+    /// Returns the debug-info model of word-sized integer types.
+    pub fn create_word_type(
+        &self,
+        flags: Option<inkwell::debug_info::DIFlags>,
+    ) -> anyhow::Result<inkwell::debug_info::DIBasicType<'ctx>> {
+        self.create_primitive_type(revive_common::BIT_LENGTH_WORD, flags)
+    }
+
+    /// Return the DIBuilder.
+    pub fn builder(&self) -> &inkwell::debug_info::DebugInfoBuilder<'ctx> {
+        &self.builder
+    }
+
+    /// Return the compilation unit. {
+    pub fn compilation_unit(&self) -> &inkwell::debug_info::DICompileUnit<'ctx> {
+        &self.compile_unit
+    }
+
+    pub fn push_scope(&self, scope: DIScope<'ctx>) -> () {
+        self.scope_stack.borrow_mut().push(scope)
+    }
+
+    pub fn pop_scope(&self) -> Option<DIScope<'ctx>> {
+        self.scope_stack.borrow_mut().pop()
+    }
+
+    pub fn num_scopes(&self) -> usize {
+        self.scope_stack.borrow().len()
+    }
+
+    pub fn top_scope(&self) -> Option<DIScope<'ctx>> {
+        self.scope_stack.borrow().top()
+    }
+
+    pub fn push_namespace(&self, name: String) -> () {
+        self.namespace_stack.borrow_mut().push(name);
+    }
+
+    pub fn pop_namespace(&self) -> Option<String> {
+        self.namespace_stack.borrow_mut().pop()
+    }
+
+    pub fn top_namespace(&self) -> Option<String> {
+        self.namespace_stack.borrow().last().map(|rc| rc.clone())
+    }
+
+    // Get a string representation of the namespace stack. Optionally append the given name.
+    pub fn namespace_as_identifier(&self, name: Option<&str>) -> String {
+        let separator = '.';
+        let mut ret = String::new();
+        let mut sep = false;
+        for s in self.namespace_stack.borrow().iter() {
+            if sep {
+                ret.push(separator);
+            };
+            sep = true;
+            ret.push_str(s.as_str())
+        }
+        if let Some(n) = name {
+            if sep {
+                ret.push(separator);
+            };
+            ret.push_str(n);
+        }
+        ret
     }
 }

crates/llvm-context/src/polkavm/context/function/declaration.rs

@@ -17,4 +17,8 @@ impl<'ctx> Declaration<'ctx> {
     ) -> Self {
         Self { r#type, value }
     }
+
+    pub fn function_value(&self) -> inkwell::values::FunctionValue<'ctx> {
+        self.value
+    }
 }

crates/llvm-context/src/polkavm/context/function/runtime/deploy_code.rs

@@ -8,6 +8,8 @@ use crate::polkavm::context::Context;
 use crate::polkavm::Dependency;
 use crate::polkavm::WriteLLVM;
 
+use inkwell::debug_info::AsDIScope;
+
 /// The deploy code function.
 /// Is a special function that is only used by the front-end generated code.
 #[derive(Debug)]
@@ -60,6 +62,47 @@ where
         context.set_basic_block(context.current_function().borrow().entry_block());
         context.set_code_type(CodeType::Deploy);
 
+        if let Some(dinfo) = context.debug_info() {
+            context.builder().unset_current_debug_location();
+            let di_builder = dinfo.builder();
+            let line_num: u32 = 0;
+            let column: u32 = 0;
+            let func_name: &str = runtime::FUNCTION_DEPLOY_CODE;
+            let linkage_name = dinfo.namespace_as_identifier(Some(func_name).clone());
+            let di_file = dinfo.compilation_unit().get_file();
+            let di_scope = di_file.as_debug_info_scope();
+            let di_func_scope = dinfo.create_function(
+                di_scope,
+                func_name,
+                Some(linkage_name.as_str()),
+                None,
+                &[],
+                di_file,
+                line_num,
+                true,
+                false,
+                false,
+                Some(inkwell::debug_info::DIFlagsConstants::PUBLIC),
+            )?;
+            let _ = dinfo.push_scope(di_func_scope.as_debug_info_scope());
+            let func_value = context
+                .current_function()
+                .borrow()
+                .declaration()
+                .function_value();
+            let _ = func_value.set_subprogram(di_func_scope);
+
+            let lexical_scope = di_builder
+                .create_lexical_block(
+                    di_func_scope.as_debug_info_scope(),
+                    dinfo.compilation_unit().get_file(),
+                    line_num,
+                    column,
+                )
+                .as_debug_info_scope();
+            let _ = dinfo.push_scope(lexical_scope);
+        }
+
         self.inner.into_llvm(context)?;
         match context
             .basic_block()
@@ -73,8 +116,30 @@ where
         }
 
         context.set_basic_block(context.current_function().borrow().return_block());
+        if let Some(dinfo) = context.debug_info() {
+            context.builder().unset_current_debug_location();
+            let di_builder = dinfo.builder();
+            let line_num: u32 = 0x0beef;
+            let di_parent_scope = dinfo
+                .top_scope()
+                .expect("expected an existing debug-info scope")
+                .clone();
+            let di_loc = di_builder.create_debug_location(
+                context.llvm(),
+                line_num,
+                0,
+                di_parent_scope,
+                None,
+            );
+            context.builder().set_current_debug_location(di_loc)
+        }
         context.build_return(None);
 
+        if let Some(dinfo) = context.debug_info() {
+            let _ = dinfo.pop_scope();
+            let _ = dinfo.pop_scope();
+        }
+
         Ok(())
     }
 }