JIT: Remove overzealous fake-splitting assert for x86 unwind info#117156
Merged
amanasifkhalid merged 1 commit intodotnet:mainfrom Jul 2, 2025
Merged
JIT: Remove overzealous fake-splitting assert for x86 unwind info#117156amanasifkhalid merged 1 commit intodotnet:mainfrom
amanasifkhalid merged 1 commit intodotnet:mainfrom
Conversation
github-actions
bot
added
the
area-CodeGen-coreclr
Contributor
There was a problem hiding this comment.
Pull Request Overview
This PR removes an overzealous debug-only assertion related to fake procedure splitting in the JIT's x86 unwind info handling. The change ensures that when fake-splitting is enabled, the JIT no longer asserts on non-root funclets, and in release builds the unwind reservation proceeds consistently.
- Remove assert in debug mode when fake procedure splitting is enabled.
- Add a comment clarifying that all unwind info is treated as hot during fake-splitting.
- Adjust the control flow to conditionally call unwindReserveFuncHelper based on the fake-splitting configuration.
Comments suppressed due to low confidence (1)
src/coreclr/jit/unwindx86.cpp:123
- Consider adding a brief comment explaining that in release builds the unwindReserveFuncHelper call always executes, while in debug builds it is skipped when fake procedure splitting is enabled. This clarification can help future maintainers understand the conditional behavior.
INDEBUG(if (!JitConfig.JitFakeProcedureSplitting()))
Contributor
|
Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch |
Contributor
Author
|
@dotnet/jit-contrib PTAL, thanks! |
This was referenced Jun 30, 2025
Contributor
Author
|
ping @dotnet/jit-contrib |
AndyAyersMS
approved these changes
Jul 2, 2025
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This assert was hit by Antigen recently. If we are doing fake hot/cold splitting, the JIT should tell the VM to reserve just one unwind info for the main function entry, regardless of whether it is split. However, we still need to reserve unwind infos for the funclets. Thus, this assert doesn't make sense.