Fix OptimizeInstructions on unreachable GC RMWs - #8485
#8485Merged
tlively merged 1 commit intoMar 18, 2026
mainWebAssembly/binaryen:mainfrom
optimize-insts-unreachable-rmwWebAssembly/binaryen:optimize-insts-unreachable-rmwCopy head branch name to clipboard
Merged
Fix OptimizeInstructions on unreachable GC RMWs#8485tlively merged 1 commit intomainWebAssembly/binaryen:mainfrom optimize-insts-unreachable-rmwWebAssembly/binaryen:optimize-insts-unreachable-rmwCopy head branch name to clipboard
tlively merged 1 commit into
mainWebAssembly/binaryen:mainfrom
optimize-insts-unreachable-rmwWebAssembly/binaryen:optimize-insts-unreachable-rmwCopy head branch name to clipboard
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OptimizeInstructions lowers RMWs on non-shared GC data to sequences of non-atomic operations. It would previously do this even for expressions with unreachable children, which caused assertion failures when trying to make unreachable scratch locals. Bail out early and leave the optimization to DCE in this case.
kripken
approved these changes
Mar 18, 2026
tlively
enabled auto-merge (squash)
March 18, 2026 18:32
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OptimizeInstructions lowers RMWs on non-shared GC data to sequences of non-atomic operations. It would previously do this even for expressions with unreachable children, which caused assertion failures when trying to make unreachable scratch locals. Bail out early and leave the optimization to DCE in this case.