[NFC] cache repeated tree walks to avoid O(N^2) in optimizeTerminatingTails in CodeFolding#8602
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Changqing-JING wants to merge 1 commit intoWebAssembly:mainfrom
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[NFC] cache repeated tree walks to avoid O(N^2) in optimizeTerminatingTails in CodeFolding#8602Changqing-JING wants to merge 1 commit intoWebAssembly:mainfrom
Changqing-JING wants to merge 1 commit intoWebAssembly:mainfrom
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In
optimizeTerminatingTails,canMoverepeatedly walked the entire function body to compute branch targets and find Try/TryTable nodes, causing O(N^2) behavior. This change caches those results lazily on first use viacanMoveWithCachedBodyInfo, and resets the cache each pass iteration. No functional change — only a compile-time performance improvement for large functions.Benmark data
For the test case in #7319 (comment)
Main head:
time ./build/bin/wasm-opt --code-folding --enable-bulk-memory --enable-multivalue --enable-reference-types --enable-gc --enable-tail-call --enable-exception-handling -o /dev/null ./test3.wasm real 7m53.093s user 8m28.756s sys 0m1.100sThis PR:
time ./build/bin/wasm-opt --code-folding --enable-bulk-memory --enable-multivalue --enable-reference-types --enable-gc --enable-tail-call --enable-exception-handling -o /dev/null ./test3.wasm real 4m25.416s user 5m1.491s sys 0m1.829s