Fix atomic RMW8/16/32 alignment checks using wrong max alignment#577
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titzer merged 2 commits intotitzer:masterfrom Mar 4, 2026
Merged
Fix atomic RMW8/16/32 alignment checks using wrong max alignment#577titzer merged 2 commits intotitzer:masterfrom
titzer merged 2 commits intotitzer:masterfrom
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Atomic RMW sub-word operations (SUB, AND, XCHG variants) have incorrect maximum alignment values due to copy-paste from the full-width RMW entries: - RMW8 ops used 4 (i32) or 8 (i64) instead of 1 - RMW16 ops used 4 (i32) or 8 (i64) instead of 2 - RMW32 ops used 8 instead of 4 This causes the validator to accept over-aligned atomic accesses that should be rejected. Fix all 15 affected entries to match the correct sub-word alignment (consistent with ADD, OR, XOR, and CMPXCHG which were already correct).
titzer
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Mar 3, 2026
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Thanks, can you please add regression tests for these?
Verify that i32.atomic.rmw8.sub_u with over-aligned memarg (align=2) is correctly rejected. RMW8 operations must have max alignment of 1.
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Details
CodeValidator.v3:1169-1201— 15 entries affected:The ADD, OR, XOR, and CMPXCHG groups already had correct values. Only SUB, AND, and XCHG were affected.