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greenhat
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memcpy (iteration guard)memcpy
Fix the byte-addressed memory paths that cross a 32-bit element boundary. This keeps the `memcpy`/`memset` fallback coverage added in this branch working for short unaligned copies, including scalarized `u16` loads and stores at byte offset 3.
Zero-length memory operations must be no-ops, but both loop headers seeded `while.true` with `count >= 0`, which executes one iteration when `count == 0`. Switch the entry condition to a strict unsigned `count > 0` check and add regressions for zero-count unaligned copy/set paths.
The unaligned `u16` regressions are asserting compiler memory layout, so they should not depend on the host endianness. Use `to_le_bytes()` in the expected byte construction to keep the tests portable and aligned with the byte-addressable memory model.
`memset` and fallback `memcpy` were carrying separate copies of the same counted `while.true` control flow, which makes fixes easy to miss in one path. Extract the shared loop header and back-edge emission so the counted loop protocol is defined once and reused by both sites.
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Only offset 3 spans two elements for a `u16` load/store. Route the other unaligned offsets through the existing single-element logic so we don't spuriously touch `addr + 1` at the end of memory.
Add regression cases for byte offsets 1 and 2 in the integration suite, and add emitter-level tests that exercise unaligned `load_imm` and `store_imm` for `u16` addresses.
Cover the aligned byte-copy fast path and a case where only `count` is misaligned so the fast-path predicate is regression-tested as well.
greenhat
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memcpymemcpy
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Close #1003
Summary
memcpy/memsetand add regression coverage for aligned and unaligned byte copies/sets, zero-length operations, and unalignedu16/i16memory accessesmemcpyfast paths so they only convert byte pointers to element addresses when the inputs are word-alignedoffset == 3through the split-word intrinsics while preserving the existing within-element path foroffset <= 2I suggest reviewing on a per-commit basis skipping non-interesting commits (refactors, etc.).