Assertion failed '!"Unexpected well known arg to method GDV candidate"

[AndyAyersMS]

https://dev.azure.com/dnceng-public/public/_build/results?buildId=1266373&view=ms.vss-test-web.build-test-results-tab&runId=35337768&resultId=209882&paneView=dotnet-dnceng.dnceng-build-release-tasks.helix-test-information-tab

windows x64 fullpgo method profiling

set DOTNET_TieredCompilation=1
set DOTNET_ReadyToRun=0
set DOTNET_TC_QuickJitForLoops=1
set DOTNET_TieredPGO=1
set DOTNET_JitDelegateProfiling=1
set DOTNET_JitVTableProfiling=1

  Discovering: System.Text.Json.Tests (method display = ClassAndMethod, method display options = None)
  Discovered:  System.Text.Json.Tests (found 10198 of 10271 test cases)
  Starting:    System.Text.Json.Tests (parallel test collections = on [4 threads], stop on fail = off)

Assert failure(PID 44644 [0x0000ae64], Thread: 22492 [0x57dc]): Assertion failed '!"Unexpected well known arg to method GDV candidate"' in 'JsonSerializerApiValidation:<SerializeNullException>b__9_1():this' during 'Importation' (IL size 25; hash 0xed53ad00; Tier1)

    File: D:\a\_work\1\s\src\coreclr\jit\importercalls.cpp:7446
    Image: C:\h\w\AB6F09F9\p\dotnet.exe

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[AndyAyersMS]

Also several failures in net11.0-windows-Release-x64-fullpgo_random_gdv_methodprofiling_only-Windows.10.Amd64.Open

DOTNET_JitClassProfiling=0
DOTNET_JitDelegateProfiling=1
DOTNET_JitRandomGuardedDevirtualization=1
DOTNET_JitRandomlyCollect64BitCounts=1
DOTNET_JitVTableProfiling=1
DOTNET_ReadyToRun=0
DOTNET_TC_QuickJitForLoops=1
DOTNET_TieredCompilation=1
DOTNET_TieredPGO=1

  Discovering: System.IO.Compression.Brotli.Tests (method display = ClassAndMethod, method display options = None)
  Discovered:  System.IO.Compression.Brotli.Tests (found 109 of 120 test cases)
  Starting:    System.IO.Compression.Brotli.Tests (parallel test collections = on [4 threads], stop on fail = off)

Assert failure(PID 16680 [0x00004128], Thread: 14112 [0x3720]): Assertion failed '!"Unexpected well known arg to method GDV candidate"' in 'System.IO.Compression.CompressionStreamUnitTestBase:RoundTripWithZLibCompressionOptions(System.String,System.IO.Compression.ZLibCompressionOptions):this' during 'Importation' (IL size 176; hash 0x03f009b8; Tier1-OSR)

    File: D:\a\_work\1\s\src\coreclr\jit\importercalls.cpp:7446

Maybe related to #123434? -- fyi @hez2010

[hez2010]

I just did a quick look but I don't think it's caused by #123434 directly. I think #123434 may expose a preexisting issue because now late devirtualization always has the base method handle for devirt so that it can lead to more devirtualization and inlining opportunities that we weren't able to do before.
If the unexpected well-known arg here is inst param, I guess there may be some work need to be done around array interface devirtualization.

[hez2010]

I just took a deeper look. The well-known arg here is AsyncContinuation.
We are trying to GDV an async call System.IO.Stream:DisposeAsync.

I believe it's related to #123448 as it enabled runtime async for all library tests.

cc @jakobbotsch

[jakobbotsch]

Thanks for looking @hez2010! This is just missing a switch case I think.