Stream: git-wasmtime

Topic: wasmtime / PR #12902 aarch64: Fix `splat(ireduce(iconst(....

Wasmtime GitHub notifications bot (Mar 31 2026 at 00:23):

alexcrichton requested cfallin for a review on PR #12902.

Wasmtime GitHub notifications bot (Mar 31 2026 at 00:23):

alexcrichton opened PR #12902 from alexcrichton:aarch64-fix-splat to bytecodealliance:main:

This commit fixes a lowering rule in the aarch64 Cranelift backend. Specifically a combined splat(ireduce(_)) combo would pass an immediate to the splat_const helper which had higher bits set since the ireduce wasn't const-propagated. The fix applied here is to delete the ireduce-related rule and rely on mid-end optimizations to trigger to fold the ireduce(iconst(...)) appropriately. This ensures that the u64 values passed into the splat_const rule is indeed the exact value that's being splatted.

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Wasmtime GitHub notifications bot (Mar 31 2026 at 00:23):

alexcrichton requested wasmtime-compiler-reviewers for a review on PR #12902.

Wasmtime GitHub notifications bot (Mar 31 2026 at 04:38):

github-actions[bot] added the label cranelift:area:aarch64 on PR #12902.

Wasmtime GitHub notifications bot (Mar 31 2026 at 04:38):

github-actions[bot] added the label cranelift on PR #12902.

Wasmtime GitHub notifications bot (Mar 31 2026 at 06:24):

cfallin submitted PR review.

Wasmtime GitHub notifications bot (Mar 31 2026 at 06:24):

cfallin added PR #12902 aarch64: Fix splat(ireduce(iconst(...))) to the merge queue

Wasmtime GitHub notifications bot (Mar 31 2026 at 06:52):

cfallin removed PR #12902 aarch64: Fix splat(ireduce(iconst(...))) from the merge queue

Wasmtime GitHub notifications bot (Mar 31 2026 at 06:52):

cfallin merged PR #12902.

Last updated: Apr 12 2026 at 23:10 UTC