Fix stale compileTimeString folds after concat assign (#36244) - #36267
Merged
Conversation
strlen() and other builtins were folding on init literals because promoteCompileTimeStringOnCallArgs walked the first ASSIGN in a block and ignored later CONCAT ops. Scan the last in-block CONCAT, sync named bindings after concat lowering, and treat loop-header null back-edges as divergent so runtime length is used. Co-authored-by: Cursor <cursoragent@cursor.com>
PurHur
added a commit
that referenced
this pull request
Sep 2, 2026
#36267) strlen() and other builtins were folding on init literals because promoteCompileTimeStringOnCallArgs walked the first ASSIGN in a block and ignored later CONCAT ops. Scan the last in-block CONCAT, sync named bindings after concat lowering, and treat loop-header null back-edges as divergent so runtime length is used. Co-authored-by: PurHur <PurHur@users.noreply.github.com> Co-authored-by: Cursor <cursoragent@cursor.com>
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 join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Summary
strlen()(and similar) folds when a string local is mutated via.=or loop concat — the initcompileTimeStringliteral was winning over later CONCAT ops.jitNamedLocalCompileTimeStringInBlock()to take the last in-block CONCAT, sync named bindings after CONCAT lowering, and treat loop-header null back-edges as divergent injitNamedLocalHasDivergentBranchCompileTimeStrings.aot_strlen_after_concat_assign_36244.phpt.Closes #36244
Verification
Not covered
script/differential-sweep.sh --aot --repeat 3(dev-verify-fast tier-0 only)make north-star5-verify-fast(no bootstrap/M5 changes)Made with Cursor