EgorBot for davidwrighton in #106843

[EgorBot]

Processing dotnet/runtime#106843 (comment) command:

Command

-intel -arm64

using BenchmarkDotNet.Attributes;
using System.Runtime.CompilerServices;

namespace VirtualDispatchChecks
{

    class _1
    {
        public virtual string Method() => "A";
    }

    class _2 : _1
    {
        public override string Method() => "B";
    }

    class _3 : _1
    {
        public override string Method() => "C";
    }

    class _4 : _1
    {
        public override string Method() => "D";
    }

    class _5 : _1
    {
        public override string Method() => "E";
    }
    class _6 : _1
    {
        public override string Method() => "F";
    }
    class _7 : _1
    {
        public override string Method() => "F";
    }

    class _8 : _1
    {
        public override string Method() => "F";
    }

    class _9 : _1
    {
        public override string Method() => "F";
    }

    class _10 : _1
    {
        public override string Method() => "F";
    }

    public class ResolveVirtualRepeatedly
    {
        static _1 _1 = new _1();
        static _1 _2 = new _2();
        static _1 _3 = new _3();
        static _1 _4 = new _4();
        static _1 _5 = new _5();
        static _1 _6 = new _6();
        static _1 _7 = new _7();
        static _1 _8 = new _8();
        static _1 _9 = new _9();
        static _1 _10 = new _10();
        [MethodImpl(MethodImplOptions.NoInlining)]
        static _1 GetA(int index)
        {
            switch (index % 10)
            {
                case 0:
                    return _10;
                case 1: return _1;
                case 2: return _2;
                case 3: return _3;
                case 4: return _4;
                case 5: return _5;
                case 6: return _6;
                case 7: return _7;
                case 8: return _8;
                case 9: return _9;
            }
            return null!;
        }

        [MethodImpl(MethodImplOptions.NoInlining)]
        static Func<string> GetAction(int index)
        {
            return GetA(index).Method;
        }

        [Benchmark]
        public void Get1Virtual()
        {
            GetAction(0);
        }

        [Benchmark]
        public void Get10Virtual()
        {
            GetAction(0);
            GetAction(1);
            GetAction(2);
            GetAction(3);
            GetAction(4);
            GetAction(5);
            GetAction(6);
            GetAction(7);
            GetAction(8);
            GetAction(9);
        }
    }
}

(EgorBot will reply in this issue)

[EgorBot]

Benchmark results on Intel

BenchmarkDotNet v0.14.0, Ubuntu 22.04.4 LTS (Jammy Jellyfish)
Intel Xeon Platinum 8370C CPU 2.80GHz, 1 CPU, 8 logical and 4 physical cores
  Job-ECHFHB : .NET 10.0.0 (42.42.42.42424), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
  Job-FJRIFJ : .NET 10.0.0 (42.42.42.42424), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI

Method	Toolchain	Mean	Error	Ratio
Get1Virtual	Main	15.77 ns	0.256 ns	1.00
Get1Virtual	PR	17.64 ns	0.217 ns	1.12
Get10Virtual	Main	179.33 ns	1.929 ns	1.00
Get10Virtual	PR	202.07 ns	1.185 ns	1.13

BDN_Artifacts.zip

[EgorBot]

cc @davidwrighton

[EgorBot]

Benchmark results on Ampere

BenchmarkDotNet v0.14.0, Ubuntu 22.04.4 LTS (Jammy Jellyfish)
Ampere
  Job-CLNVZZ : .NET 10.0.0 (42.42.42.42424), Arm64 RyuJIT AdvSIMD
  Job-HQMPJB : .NET 10.0.0 (42.42.42.42424), Arm64 RyuJIT AdvSIMD

Method	Toolchain	Mean	Error	Ratio
Get1Virtual	Main	23.08 ns	0.335 ns	1.00
Get1Virtual	PR	21.91 ns	0.169 ns	0.95
Get10Virtual	Main	237.93 ns	1.455 ns	1.00
Get10Virtual	PR	216.98 ns	1.825 ns	0.91

BDN_Artifacts.zip