Fix Memory64Lowering table.copy size wrapping for mixed tables#8319
Merged
kripken merged 1 commit intoWebAssembly:mainfrom Feb 13, 2026
Merged
Fix Memory64Lowering table.copy size wrapping for mixed tables#8319kripken merged 1 commit intoWebAssembly:mainfrom
kripken merged 1 commit intoWebAssembly:mainfrom
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visitTableCopy wrapped curr->size using only the dest table's type, but the size operand is i64 only when both source and dest tables are 64-bit. When copying between tables of different address types, wrapping an i32 size as if it were i64 causes an assertion failure. Check both tables before wrapping the size operand, matching the type logic in child-typer.h.
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Summary
visitTableCopywrappedcurr->sizeusing only the dest table's type, but the wasm spec (andchild-typer.h) defines the size type as i64 only when both source and dest tables are 64-bit. When copying between a 64-bit and a 32-bit table, the size is i32, but wrapping checks only the dest table — causing an assertion failure (assert(ptr->type == Type::i64)) when dest is 64-bit but source is 32-bit.Fix: Check both tables before wrapping the size operand, matching the type logic in
child-typer.h.Split from #8311 per review feedback.
Test plan
memory64-lowering-table-copy.wastcovering: