Stream: git-wasmtime

Topic: wasmtime / PR #13271 winch/aarch64: implement the wide-ar...

Wasmtime GitHub notifications bot (May 05 2026 at 01:54):

darioush opened PR #13271 from darioush:winch-aarch64-wide-arithmetic to bytecodealliance:main:

Replace the unimplemented stubs for add128, sub128, and mul_wide on aarch64 with real implementations using ADDS+ADC, SUBS+SBC, and MUL+UMULH/SMULH respectively, and drop the gate that forced the wide-arithmetic feature off when targeting Winch on aarch64.

For mul_wide the high-half multiply is emitted before the low-half multiply because the low-half destination aliases an input register.

Issue: #11929

Wasmtime GitHub notifications bot (May 05 2026 at 02:08):

darioush edited PR #13271:

Replace the unimplemented stubs for add128, sub128, and mul_wide on aarch64 with implementations using ADDS+ADC, SUBS+SBC, and MUL+UMULH/SMULH respectively, and drop the gate that forced the wide-arithmetic feature off when targeting Winch on aarch64.

For mul_wide the high-half multiply is emitted before the low-half multiply because the low-half destination aliases an input register.

Issue: #11929

Wasmtime GitHub notifications bot (May 05 2026 at 02:12):

darioush has marked PR #13271 as ready for review.

Wasmtime GitHub notifications bot (May 05 2026 at 02:12):

darioush requested Copilot for a review on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 02:12):

darioush requested alexcrichton for a review on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 02:12):

darioush requested wasmtime-core-reviewers for a review on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 02:12):

darioush requested wasmtime-compiler-reviewers for a review on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 06:27):

github-actions[bot] added the label wasmtime:config on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 06:27):

github-actions[bot] added the label wasmtime:api on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 06:27):

github-actions[bot] added the label winch on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 06:28):

github-actions[bot] commented on PR #13271:

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Wasmtime GitHub notifications bot (May 05 2026 at 07:27):

github-actions[bot] commented on PR #13271:

Label Messager: wasmtime:config

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Wasmtime GitHub notifications bot (May 05 2026 at 11:25):

:memo: saulecabrera submitted PR review:

Could you add some disassembly tests as well?

Wasmtime GitHub notifications bot (May 05 2026 at 13:23):

darioush updated PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 13:52):

darioush updated PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 15:02):

alexcrichton unassigned alexcrichton from PR #13271 winch/aarch64: implement the wide-arithmetic proposal.

Wasmtime GitHub notifications bot (May 05 2026 at 15:02):

alexcrichton requested saulecabrera for a review on PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 17:16):

:thumbs_up: saulecabrera submitted PR review:

This looks reasonable to me, left one comment which I think is worth addressing before merging. Thanks!

Wasmtime GitHub notifications bot (May 05 2026 at 17:16):

:speech_balloon: saulecabrera created PR review comment:

Could we avoid introducing this method here and instead refactor the existing subs_rrr implementation to take a destination register? For call sites that want to discard the destination register e.g., cmp, we could pass writable!(regs::zero())

Wasmtime GitHub notifications bot (May 05 2026 at 18:20):

darioush updated PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 18:21):

darioush updated PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 18:40):

:memo: darioush submitted PR review.

Wasmtime GitHub notifications bot (May 05 2026 at 18:40):

:speech_balloon: darioush created PR review comment:

Thanks for the quick reviews, really appreciate your time and consideration. Done in ad376da

Wasmtime GitHub notifications bot (May 05 2026 at 18:55):

saulecabrera added PR #13271 winch/aarch64: implement the wide-arithmetic proposal to the merge queue.

Wasmtime GitHub notifications bot (May 05 2026 at 19:22):

:check: saulecabrera merged PR #13271.

Wasmtime GitHub notifications bot (May 05 2026 at 19:22):

saulecabrera removed PR #13271 winch/aarch64: implement the wide-arithmetic proposal from the merge queue.

Last updated: Jun 01 2026 at 09:49 UTC