Fix Precompute visitArrayGet missing memory ordering check#8327
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sumleo wants to merge 1 commit intoWebAssembly:mainfrom
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Fix Precompute visitArrayGet missing memory ordering check#8327sumleo wants to merge 1 commit intoWebAssembly:mainfrom
sumleo wants to merge 1 commit intoWebAssembly:mainfrom
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visitStructGet correctly checks MemoryOrder before allowing precomputation of immutable fields (blocking SeqCst and shared AcqRel), but visitArrayGet skips this check entirely. This causes array.atomic.get with SeqCst or AcqRel ordering on immutable array elements to be incorrectly folded to constants, removing synchronization semantics. Add the same MemoryOrder switch to visitArrayGet matching the pattern in visitStructGet, and extend the existing precompute-gc-atomics test with array versions of all struct atomic get test cases.
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Summary
visitStructGetin the precompute pass correctly checksMemoryOrderbefore allowing precomputation of immutable fields—blockingSeqCstentirely and blocking sharedAcqRel—butvisitArrayGetskips this check.array.atomic.getwithSeqCstorAcqRelordering on immutable array elements to be incorrectly constant-folded, removing synchronization semantics.MemoryOrderswitch tovisitArrayGetmatching the existing pattern invisitStructGet.Test plan
test/lit/passes/precompute-gc-atomics.wastwith array versions of all six existing struct atomic get test cases (unordered/seqcst/acqrel x shared/unshared), verifying array atomics now follow the same optimization rules as struct atomics.