[browser] TensorPrimitivesTests.ConvertToHalf_SpecialValues `-Infinity`

[pavelsavara]

Error Blob

{
  "ErrorMessage": "[FAIL] System.Numerics.Tensors.Tests.TensorPrimitivesTests.ConvertToHalf_SpecialValues",
  "BuildRetry": false,
  "ErrorPattern": "",
  "ExcludeConsoleLog": false
}

Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=424283&view=results

Reproduction Steps

Log

fail: [FAIL] System.Numerics.Tensors.Tests.TensorPrimitivesTests.ConvertToHalf_SpecialValues(tensorLength: 15)
info: Assert.Equal() Failure
info: Expected: NaN
info: Actual:   -Infinity
info:    at System.Numerics.Tensors.Tests.TensorPrimitivesTests.ConvertToHalf_SpecialValues(Int32 tensorLength)
info:    at System.Object.InvokeStub_TensorPrimitivesTests.ConvertToHalf_SpecialValues(Object , Span`1 )
info:    at System.Reflection.MethodBaseInvoker.InvokeWithOneArg(Object , BindingFlags , Binder , Object[] , CultureInfo )

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=424283
Error message validated: [FAIL] System.Numerics.Tensors.Tests.TensorPrimitivesTests.ConvertToHalf_SpecialValues
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 10/2/2023 12:36:04 PM UTC

Report

Build	Definition	Test	Pull Request
425496	dotnet/runtime	normal-System.Numerics.Tensors.Tests.WorkItemExecution
425041	dotnet/runtime	normal-System.Numerics.Tensors.Tests.WorkItemExecution
424643	dotnet/runtime	normal-System.Numerics.Tensors.Tests.WorkItemExecution	#92226
424283	dotnet/runtime	normal-System.Numerics.Tensors.Tests.WorkItemExecution	#92871
424272	dotnet/runtime	normal-System.Numerics.Tensors.Tests.WorkItemExecution
423892	dotnet/runtime	normal-System.Numerics.Tensors.Tests.WorkItemExecution

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
0	0	6

Tagging subscribers to 'arch-wasm': @lewing
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Error Blob

{
  "ErrorMessage": "[FAIL] System.Numerics.Tensors.Tests.TensorPrimitivesTests.ConvertToHalf_SpecialValues",
  "BuildRetry": false,
  "ErrorPattern": "",
  "ExcludeConsoleLog": false
}

Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=424283&view=results

Reproduction Steps

Log

fail: [FAIL] System.Numerics.Tensors.Tests.TensorPrimitivesTests.ConvertToHalf_SpecialValues(tensorLength: 15)
info: Assert.Equal() Failure
info: Expected: NaN
info: Actual:   -Infinity
info:    at System.Numerics.Tensors.Tests.TensorPrimitivesTests.ConvertToHalf_SpecialValues(Int32 tensorLength)
info:    at System.Object.InvokeStub_TensorPrimitivesTests.ConvertToHalf_SpecialValues(Object , Span`1 )
info:    at System.Reflection.MethodBaseInvoker.InvokeWithOneArg(Object , BindingFlags , Binder , Object[] , CultureInfo )

Author:	pavelsavara
Assignees:	-
Labels:	arch-wasm, area-System.Numerics, blocking-clean-ci, Known Build Error, os-browser
Milestone:	9.0.0

[pavelsavara]

cc @stephentoub

[stephentoub]

Thanks, @pavelsavara. This test should be deterministic. Is this from a leg that's not normally run during CI, and if so, how do I trigger it?

[pavelsavara]

It's wasm AOT, you can trigger it with /azp run runtime-wasm comment in a PR

I guess our LLVM settings prefer speed over behavioral consistency.

@vargaz may know more.

[vargaz]

Can't reproduce this. Is it reproducible on CI ?

[pavelsavara]

Can't reproduce this. Is it reproducible on CI ?

Yes, see https://helixre107v0xdcypoyl9e7f.blob.core.windows.net/dotnet-runtime-refs-pull-92871-merge-34417cc5806d46a084/normal-System.Numerics.Tensors.Tests/1/console.c43b761f.log?helixlogtype=result

[vargaz]

Its reproducible when simd is enabled.

[vargaz]

Testcase:

using System;
using System.Runtime.Intrinsics;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

internal class Program
{
    private static void Main(string[] args)
    {
        var value = Vector128.Create (float.NaN);
        var v2 = Vector128.Create(args.Length == 0 ? 65520.0f : 0.0f);
        value = Vector128.Min(v2, value);
        Console.WriteLine (value);
    }
}

Without simd:
<NaN, NaN, NaN, NaN>
With simd:
<65520, 65520, 65520, 65520>