JIT: Assertion failed '!"Write to unaliased local overlaps outstanding read"' during 'Rationalize IR'

[jakobbotsch]

Created based on an example generated by Antigen.

using System.Runtime.CompilerServices;

public class Program
{
    public static void Main(string[] args)
    {
        S s = default;
        if (args.Length > 0)
        {
            s.A = 1234;
        }

        Foo(0, 0, s, s);
    }

    [MethodImpl(MethodImplOptions.NoInlining)]
    private static void Foo(int a, int b, S s1, S s2)
    {
    }

    public struct S
    {
        public int A;
    }
}

Run on win-x86 with

$env:DOTNET_JitNoCse=1
$env:DOTNET_JitStressModeNames="STRESS_NO_OLD_PROMOTION STRESS_PHYSICAL_PROMOTION_COST"
$env:DOTNET_TieredCompilation=0

Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Created based on an example generated by Antigen.

using System.Runtime.CompilerServices;

public class Program
{
    public static void Main(string[] args)
    {
        S s = default;
        if (args.Length > 0)
        {
            s.A = 1234;
        }

        Foo(0, 0, s, s);
    }

    [MethodImpl(MethodImplOptions.NoInlining)]
    private static void Use(int x)
    {
    }

    [MethodImpl(MethodImplOptions.NoInlining)]
    private static void Foo(int a, int b, S s1, S s2)
    {
    }

    public struct S
    {
        public int A;
    }
}

Run with

$env:DOTNET_JitNoCse=1
$env:DOTNET_JitStressModeNames="STRESS_NO_OLD_PROMOTION STRESS_PHYSICAL_PROMOTION_COST"
$env:DOTNET_TieredCompilation=0

Author:	jakobbotsch
Assignees:	-
Labels:	area-CodeGen-coreclr, untriaged
Milestone:	-