JIT: Loop alignment related assertion failure during 'Generate code'

[jakobbotsch]

Error Blob

{
  "ErrorMessage": "",
  "BuildRetry": false,
  "ErrorPattern": "Assertion failed 'false'.*TryMatchAtCurrentPosition.*during 'Generate code'",
  "ExcludeConsoleLog": false
}

on win-x86.

Reproduction Steps

Example test run: https://dev.azure.com/dnceng-public/public/_build/results?buildId=536322&view=results
Example console log: https://helixre107v0xdcypoyl9e7f.blob.core.windows.net/dotnet-runtime-refs-pull-97327-merge-671f49475e39419b85/System.Text.RegularExpressions.Tests/1/console.52e8f84c.log?helixlogtype=result

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=536322
Error message validated: Assertion failed 'false'.*TryMatchAtCurrentPosition.*during 'Generate code'
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 1/23/2024 11:42:32 AM UTC

Report

Build	Definition	Test	Pull Request
536322	dotnet/runtime	System.Text.RegularExpressions.Tests.WorkItemExecution	#97327
536006	dotnet/runtime	System.Text.RegularExpressions.Tests.WorkItemExecution

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
0	2	2

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

---

Error Blob

{
  "ErrorMessage": "",
  "BuildRetry": false,
  "ErrorPattern": "Assertion failed 'false'.*TryMatchAtCurrentPosition.*during 'Generate code'",
  "ExcludeConsoleLog": false
}

on win-x86.

Reproduction Steps

Example test run: https://dev.azure.com/dnceng-public/public/_build/results?buildId=536322&view=results
Example console log: https://helixre107v0xdcypoyl9e7f.blob.core.windows.net/dotnet-runtime-refs-pull-97327-merge-671f49475e39419b85/System.Text.RegularExpressions.Tests/1/console.52e8f84c.log?helixlogtype=result

Author:	jakobbotsch
Assignees:	-
Labels:	area-CodeGen-coreclr, blocking-clean-ci-optional, Known Build Error
Milestone:	-

[jakobbotsch]

@BruceForstall Is #97367 fixing this issue? I hit it in the libraries-jitstress run in #97327

[BruceForstall]

It's the same assert, so my guess would be "yes".

[amanasifkhalid]

Since #97367 has been merged, should we close this? The assert hasn't hit recently.

[BruceForstall]

Makes sense.