fix(Heap2Local): Track RMW results to handle nested flows (#8850) - #9081
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fix(Heap2Local): Track RMW results to handle nested flows (#8850)#9081ArkadySkv wants to merge 1 commit into
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…y#8850) Add RMW result tracking infrastructure to handle cases where an inner cmpxchg result flows into the value operand of an outer xchg. - Add RMWResultInfo struct and RMWResultInfoMap - Extend EscapeAnalyzer to follow RMW result flows - Modify visitStructRMW and visitStructCmpxchg to detect nested flows - Store reference-typed RMW results in scratch locals for downstream use Fixes WebAssembly#8850.
ArkadySkv
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September 7, 2026 11:22
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This PR fixes a bug in Heap2Local where nested atomic RMW operations
were incorrectly optimized.
When an inner cmpxchg result flows into the value operand of an outer
xchg, the pass now correctly tracks this data flow and preserves the
RMW operations while localizing their ref operands.
The fix adds RMW result tracking infrastructure (
RMWResultInfo) andextends
EscapeAnalyzer,visitStructRMW, andvisitStructCmpxchgto handle nested flows.
Tested with:
heap2local-rmw.wastlit testAll tests pass (4 d8-related failures are unrelated and due to local
environment).
Fixes #8850.