fix: compound assignment with side-effect in lhs miscompiles#2992
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XMadrid wants to merge 8 commits intoAssemblyScript:mainfrom
Open
fix: compound assignment with side-effect in lhs miscompiles#2992XMadrid wants to merge 8 commits intoAssemblyScript:mainfrom
XMadrid wants to merge 8 commits intoAssemblyScript:mainfrom
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Fixes #2730 .
This PR fixes a compound-assignment codegen bug where the lhs could be evaluated twice (for example, in patterns like method-call receivers or indexed access), causing duplicated side effects.
Changes proposed in this pull request:
⯈Added a side-effect cache path for compound assignment in the compiler so side-effectful receiver/index expressions are evaluated once and reused.
⯈Introduced helper logic to detect cache-eligible targets (property/element access) and side-effectful sub-expressions
⯈The reason so many test fixtures are affected is that there is a match assignment statement on line 375 of rt/tlsf.ts, which lhs gets compiled twice (which is semantically incorrect).