Assertion failed '!varTypeUsesFloatReg(targetType) || (emitTypeSize(targetType) == emitTypeSize(op1Type))'

[BruceForstall]

Failure in System.Numerics.Vectors.Tests in many variations of runtime-coreclr libraries-jitstress pipeline.

https://dev.azure.com/dnceng-public/public/_build/results?buildId=140597&view=ms.vss-test-web.build-test-results-tab&runId=3049944&resultId=199871&paneView=dotnet-dnceng.dnceng-build-release-tasks.helix-test-information-tab

Assert failure(PID 4676 [0x00001244], Thread: 4260 [0x10a4]): Assertion failed '!varTypeUsesFloatReg(targetType) || (emitTypeSize(targetType) == emitTypeSize(op1Type))' in 'System.Numerics.Tests.Matrix3x2Tests:Matrix3x2EqualsNaNTest():this' during 'Generate code' (IL size 763; hash 0xd96aa0b9; FullOpts)

    File: D:\a\_work\1\s\src\coreclr\jit\codegenxarch.cpp Line: 4927
    Image: C:\h\w\9E2F091C\p\dotnet.exe

@dotnet/jit-contrib

[ghost]

Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch, @kunalspathak
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Issue Details

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Failure in System.Numerics.Vectors.Tests in many variations of runtime-coreclr libraries-jitstress pipeline.

https://dev.azure.com/dnceng-public/public/_build/results?buildId=140597&view=ms.vss-test-web.build-test-results-tab&runId=3049944&resultId=199871&paneView=dotnet-dnceng.dnceng-build-release-tasks.helix-test-information-tab

Assert failure(PID 4676 [0x00001244], Thread: 4260 [0x10a4]): Assertion failed '!varTypeUsesFloatReg(targetType) || (emitTypeSize(targetType) == emitTypeSize(op1Type))' in 'System.Numerics.Tests.Matrix3x2Tests:Matrix3x2EqualsNaNTest():this' during 'Generate code' (IL size 763; hash 0xd96aa0b9; FullOpts)

    File: D:\a\_work\1\s\src\coreclr\jit\codegenxarch.cpp Line: 4927
    Image: C:\h\w\9E2F091C\p\dotnet.exe

@dotnet/jit-contrib

Author:	BruceForstall
Assignees:	-
Labels:	JitStress, area-CodeGen-coreclr, blocking-clean-ci-optional
Milestone:	8.0.0

[JulieLeeMSFT]

Assigned to @TIHan for assert in Code Gen.
CC @dotnet/jit-contrib.

[tannergooding]

The first run I see this in is https://dev.azure.com/dnceng-public/public/_build/results?buildId=138109&view=results which corresponds to my PR #80626

Notably I had run jitstress, but not the libraries-jitstress variant, just the outerloop, isas-x86, and isas-x64. I'm guessing there is some edge case that is only covered by libraries tests atm.

[TIHan]

I have a minimal repo so far:

Matrix3x2 a = new Matrix3x2(float.NaN, 0, 0, 0, 0, 0);
Assert.False(a.Equals(new Matrix3x2()));