Wasmtime GitHub notifications bot (Jun 05 2026 at 22:37): Wasmtime GitHub notifications bot (Jun 05 2026 at 22:37):alexcrichton opened PR #13577 from alexcrichton:fix-chunked-big-copy to bytecodealliance:main:
This commit fixes a bug in the previous refactorings of
memory.copyor other bulk copy instructions. Notably when fuel/epochs were enabled the operation was chunked up to check fuel between each operation, but the advancement of what to do unconditionally went forwards. When a backwards copy is required this means that data could get corrupted if the src/dst regions are overlapping. The fix here is to setup a separate backwards-copy loop which handles this case so the fuel/epoch-metered copy goes either backwards or forwards depending on what's being copied.<!--
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Wasmtime GitHub notifications bot (Jun 05 2026 at 22:37):alexcrichton requested cfallin for a review on PR #13577.
Wasmtime GitHub notifications bot (Jun 05 2026 at 22:37):alexcrichton requested wasmtime-compiler-reviewers for a review on PR #13577.
Wasmtime GitHub notifications bot (Jun 05 2026 at 22:37):alexcrichton requested wasmtime-core-reviewers for a review on PR #13577.
Wasmtime GitHub notifications bot (Jun 05 2026 at 22:57)::thumbs_up: cfallin submitted PR review:
Thanks!
Wasmtime GitHub notifications bot (Jun 05 2026 at 22:57):cfallin added PR #13577 Fix large, backwards, memory.copy with fuel/epochs to the merge queue.
Wasmtime GitHub notifications bot (Jun 05 2026 at 23:21)::check: cfallin merged PR #13577.
Wasmtime GitHub notifications bot (Jun 05 2026 at 23:21):cfallin removed PR #13577 Fix large, backwards, memory.copy with fuel/epochs from the merge queue.
Last updated: Jul 29 2026 at 05:03 UTC