Runtime: AsciiUtilityTests failing in CI and PR

Created on 20 Mar 2020 · 11Comments · Source: dotnet/runtime

Specifically the following tests:

System.Text.Tests.AsciiUtilityTests.GetIndexOfFirstNonAsciiByte_Vector128InnerLoop
System.Text.Tests.AsciiUtilityTests.GetIndexOfFirstNonAsciiChar_Boundaries
System.Tests.UriCreateStringTests.Scheme_Authority_IdnHost
System.Tests.UriMethodTests.GetComponents

Console Log Summary

Generally the stack trace is the following:

    System.Text.Tests.AsciiUtilityTests.GetIndexOfFirstNonAsciiByte_Vector128InnerLoop [FAIL]
      System.PlatformNotSupportedException : Operation is not supported on this platform.
      Stack Trace:
        /_/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Sse2.cs(673,0): at System.Runtime.Intrinsics.X86.Sse2.LoadVector128(Byte* address)
        /_/src/libraries/System.Private.CoreLib/src/System/Text/ASCIIUtility.cs(494,0): at System.Text.ASCIIUtility.GetIndexOfFirstNonAsciiByte_Sse2(Byte* pBuffer, UInt64 bufferLength)
        /_/src/libraries/System.Runtime/tests/System/Text/ASCIIUtilityTests.cs(394,0): at System.Text.Tests.AsciiUtilityTests.CallGetIndexOfFirstNonAsciiByte(ReadOnlySpan`1 buffer)
        /_/src/libraries/System.Runtime/tests/System/Text/ASCIIUtilityTests.cs(71,0): at System.Text.Tests.AsciiUtilityTests.GetIndexOfFirstNonAsciiByte_Vector128InnerLoop()
      System.PlatformNotSupportedException : Operation is not supported on this platform.

Builds

|Build|Pull Request | Test Failure Count|
| --- | --- | --- |
|#557918|Rolling|1|
|#558017|Rolling|1|
|#558485|Rolling|1|
|#558582|Rolling|1|
|#558716|Rolling|1|
|#559049|Rolling|1|
|#559300|Rolling|1|
|#559370|Rolling|2|
|#559451|Rolling|2|
|#559583|Rolling|2|
|#559682|Rolling|1|
|#559846|Rolling|2|
|#565608|Rolling|19|
|#565828|Rolling|18|
|#566046|Rolling|21|
|#566217|Rolling|22|
|#566391|Rolling|16|
|#566510|Rolling|19|
|#566655|Rolling|18|
|#566731|Rolling|17|
|#566876|Rolling|20|
|#567099|Rolling|19|
|#567233|Rolling|15|
|#566655|Rolling|3|
|#566731|Rolling|1|
|#566876|Rolling|3|
|#567099|Rolling|2|
|#567233|Rolling|3|

Configurations

netcoreapp5.0-Linux-Release-arm64-CoreCLR_release-(Alpine.38.Arm64.Open)Ubuntu.1804.ArmArch.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:alpine-3.8-helix-arm64v8-a45aeeb-20190620184035
netcoreapp5.0-Linux-Release-x64-CoreCLR_checked-(Alpine.311.Amd64.Open)Ubuntu.1604.Amd64.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:alpine-3.11-helix-bfcd90a-20200123191053
netcoreapp5.0-Linux-Release-x64-CoreCLR_checked-Ubuntu.1804.Amd64.Open
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-(Alpine.310.Amd64.Open)ubuntu.1604.amd64.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:alpine-3.10-helix-bfcd90a-20200123191054
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-(Alpine.311.Amd64.Open)ubuntu.1604.amd64.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:alpine-3.11-helix-bfcd90a-20200123191053
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-(Alpine.39.Amd64.Open)ubuntu.1604.amd64.open@mcr.microsoft.com/dotnet-buildtools/prereqs:alpine-3.9-helix-bfcd90a-20200123191053
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-(Debian.10.Amd64.Open)ubuntu.1604.amd64.open@mcr.microsoft.com/dotnet-buildtools/prereqs:debian-10-helix-amd64-bfcd90a-20200121150006
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-(Fedora.29.Amd64.Open)ubuntu.1604.amd64.open@mcr.microsoft.com/dotnet-buildtools/prereqs:fedora-29-helix-a12566d-20191210224553
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-(Fedora.30.Amd64.Open)ubuntu.1604.amd64.open@mcr.microsoft.com/dotnet-buildtools/prereqs:fedora-30-helix-4f8cef7-20200121150022
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-(Ubuntu.1910.Amd64.Open)ubuntu.1604.amd64.open@mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-19.10-helix-amd64-cfcfd50-20191030180623
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-Centos.7.Amd64.Open
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-Debian.9.Amd64.Open
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-RedHat.7.Amd64.Open
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-SLES.12.Amd64.Open
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-SLES.15.Amd64.Open
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-Ubuntu.1604.Amd64.Open
netcoreapp5.0-Linux-Release-x64-CoreCLR_release-Ubuntu.1804.Amd64.Open
netcoreapp5.0-OSX-Release-x64-CoreCLR_checked-OSX.1013.Amd64.Open
netcoreapp5.0-OSX-Release-x64-CoreCLR_release-OSX.1013.Amd64.Open
netcoreapp5.0-OSX-Release-x64-CoreCLR_release-OSX.1014.Amd64.Open
netcoreapp5.0-Windows_NT-Release-x64-CoreCLR_checked-Windows.10.Amd64.Open
netcoreapp5.0-Windows_NT-Release-x64-CoreCLR_release-(Windows.Nano.1809.Amd64.Open)windows.10.amd64.serverrs5.open@mcr.microsoft.com/dotnet-buildtools/prereqs:nanoserver-1809-helix-amd64-08e8e40-20200107182504
netcoreapp5.0-Windows_NT-Release-x64-CoreCLR_release-Windows.10.Amd64.Server19H1.Open
netcoreapp5.0-Windows_NT-Release-x64-CoreCLR_release-Windows.10.Amd64.ServerRS5.Open
netcoreapp5.0-Windows_NT-Release-x64-CoreCLR_release-Windows.7.Amd64.Open
netcoreapp5.0-Windows_NT-Release-x64-CoreCLR_release-Windows.81.Amd64.Open
netcoreapp5.0-Windows_NT-Release-x86-CoreCLR_checked-Windows.10.Amd64.Open

Helix Logs

area-Infrastructure blocking-clean-ci untriaged

Source

jaredpar

Most helpful comment

It turns out that due to tiered compilation, that the check around Sse2.IsSupported isn't actually handled correctly, the rules for how crossgen and tiered compilation work, make it unsafe to perform an IsSupported check and then call a helper function if the result of IsSupported may vary between crossgen time and runtime. However, that should only be a problem for the Avx variants of generated code in crossgen, not for stuff which is compiled as optimistically supported in crossgen.

My suspicion is that the problem is a runtime triggered tiered rejit not considering SSE2 to be active. I'm building the product now to verify, but I'm pretty sure its not the crossgen behavior, but the rejit behavior that is getting us in trouble here.

davidwrighton on 21 Mar 2020

👍2

All 11 comments

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