Do not retype small locals in FIELD_LISTs on x86

[SingleAccretion]

This is not correct for normalize-on-load register candidates.

Fixes#73951.
Fixes#74562.

A tiny regression on x86, due to using extending moves in more cases.

[ghost]

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

Issue Details

---

This is not correct for normalize-on-load register candidates.

Fixes #73951.

Author:	SingleAccretion
Assignees:	-
Labels:	area-CodeGen-coreclr
Milestone:	-

[SingleAccretion]

SPMI failures look pre-existing.

@dotnet/jit-contrib

[BruceForstall]

@SingleAccretion When I run the new unit test locally, it passes even without your fix. I'm on 676a6bb

Also, I notice when building the test locally I get a warning:

Program.cs(11,28): warning CS8618: Non-nullable field 's_rt' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

I don't see this in the CI build, but maybe they suppress all warnings?

[SingleAccretion]

Hmm, that is very strange. I don't see any nullability warnings locally:

C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951> dotnet build
MSBuild version 17.4.0-preview-22378-04+827c1bf9c for .NET
Determining projects to restore...
Restored C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951.csproj (in 219 ms).
Restored C:\Users\Accretion\source\dotnet\runtime\src\tests\Common\XUnitWrapperGenerator\XUnitWrapperGenerator.csproj (in 235 ms).
C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\packages\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951\Runtime_73951.csproj.nuget.g.props(17,5): warning MSB4011: "C
:\Users\Accretion\.nuget\packages\microsoft.net.illink.tasks\7.0.100-1.22415.4\build\Microsoft.NET.ILLink.Tasks.props" cannot be imported again. It was already imported at "C:\Users\Accr
etion\source\dotnet\runtime\artifacts\tests\coreclr\packages\Common\test_dependencies\test_dependencies\test_dependencies.csproj.nuget.g.props (16,5)". This is most likely a build author
ing error. This subsequent import will be ignored. [C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951.csproj]
C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\packages\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951\Runtime_73951.csproj.nuget.g.props(18,5): warning MSB4011: "C
:\Users\Accretion\.nuget\packages\microsoft.net.compilers.toolset\4.4.0-2.22412.11\build\Microsoft.Net.Compilers.Toolset.props" cannot be imported again. It was already imported at "C:\U
sers\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\packages\Common\test_dependencies\test_dependencies\test_dependencies.csproj.nuget.g.props (17,5)". This is most likely a bui
ld authoring error. This subsequent import will be ignored. [C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951.csproj]
XUnitWrapperGenerator -> C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\windows.x64.Debug\Common\XUnitWrapperGenerator\XUnitWrapperGenerator\XUnitWrapperGenerator.dll
Runtime_73951 -> C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\windows.x64.Debug\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951\Runtime_73951.dll
Build succeeded.
C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\packages\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951\Runtime_73951.csproj.nuget.g.props(17,5): warning MSB4011: "C
:\Users\Accretion\.nuget\packages\microsoft.net.illink.tasks\7.0.100-1.22415.4\build\Microsoft.NET.ILLink.Tasks.props" cannot be imported again. It was already imported at "C:\Users\Accr
etion\source\dotnet\runtime\artifacts\tests\coreclr\packages\Common\test_dependencies\test_dependencies\test_dependencies.csproj.nuget.g.props (16,5)". This is most likely a build author
ing error. This subsequent import will be ignored. [C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951.csproj]
C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\packages\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951\Runtime_73951.csproj.nuget.g.props(18,5): warning MSB4011: "C
:\Users\Accretion\.nuget\packages\microsoft.net.compilers.toolset\4.4.0-2.22412.11\build\Microsoft.Net.Compilers.Toolset.props" cannot be imported again. It was already imported at "C:\U
sers\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\packages\Common\test_dependencies\test_dependencies\test_dependencies.csproj.nuget.g.props (17,5)". This is most likely a bui
ld authoring error. This subsequent import will be ignored. [C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951.csproj]
2 Warning(s)
0 Error(s)
Time Elapsed 00:00:10.44

Certainly, I would expect our test built to globally disable nullability.

And the test does fail without and pass with the fix:

C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951> set-test-env -a x86 -b
CORE_ROOT: C:\Users\Accretion\source\dotnet\runtime-base\artifacts\tests\coreclr\windows.x86.Checked\Tests\Core_Root
DOTNET_TieredCompilation: 0
# The "base" commit is '14a65ecaf86207b24d4aba6ff84806f87eacb993'
PS C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951> C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\windows.x64.Debug\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951\Runtime_73951.cmd
BEGIN EXECUTION
"C:\Users\Accretion\source\dotnet\runtime-base\artifacts\tests\coreclr\windows.x86.Checked\Tests\Core_Root\corerun.exe" Runtime_73951.dll
Expected: 100
Actual: 101
END EXECUTION - FAILED
FAILED
PS C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951> set-test-env -a x86
CORE_ROOT: C:\Users\Accretion\source\dotnet\build\CustomCoreRoot_x86
DOTNET_TieredCompilation: 0
PS C:\Users\Accretion\source\dotnet\runtime\src\tests\JIT\Regression\JitBlue\Runtime_73951> C:\Users\Accretion\source\dotnet\runtime\artifacts\tests\coreclr\windows.x64.Debug\JIT\Regression\JitBlue\Runtime_73951\Runtime_73951\Runtime_73951.cmd
BEGIN EXECUTION
"C:\Users\Accretion\source\dotnet\build\CustomCoreRoot_x86\corerun.exe" Runtime_73951.dll
Expected: 100
Actual: 100
END EXECUTION - PASSED
PASSED

There is a detail in the test (the original Fuzzlyn code from which it was adapted also has this property) that to fail it needs to read some random bits from the stack, so perhaps it could be influenced by the environment...?

(But it does fail for me consistently, FWIW)

[JulieLeeMSFT]

@BruceForstall please backport this to 7.0 once all tests pass.

[BruceForstall]

I was able to (finally) reproduce the baseline failure and diff code non-failure.

[BruceForstall]

/backport to release/7.0

[github-actions]

Started backporting to release/7.0: https://github.com/dotnet/runtime/actions/runs/2982283022