Wasmtime GitHub notifications bot (Oct 10 2026 at 01:56): Wasmtime GitHub notifications bot (Oct 10 2026 at 01:56):cfallin opened PR #14652 from cfallin:fix-i128-shift-amounts to bytecodealliance:main:
In several lowering rules that match on patterns around shifts, an i128-sized shift amount caused a compiler panic because its representation consists of multiple registers. Shifts in Cranelift always mask the shift amount (to a power-of-2) so taking the low 64-bit register of the shift amount is correct/lossless and avoids the panic.
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Wasmtime GitHub notifications bot (Oct 10 2026 at 01:56):cfallin requested alexcrichton for a review on PR #14652.
Wasmtime GitHub notifications bot (Oct 10 2026 at 01:56):cfallin requested wasmtime-compiler-reviewers for a review on PR #14652.
Wasmtime GitHub notifications bot (Oct 10 2026 at 02:44)::thumbs_up: alexcrichton submitted PR review.
Wasmtime GitHub notifications bot (Oct 10 2026 at 02:45):alexcrichton has enabled auto merge for PR #14652.
Wasmtime GitHub notifications bot (Oct 10 2026 at 03:56):alexcrichton added PR #14652 Cranelift: x64: fix i128 shift amounts in several lowering rules. to the merge queue
Wasmtime GitHub notifications bot (Oct 10 2026 at 04:51):github-actions[bot] added the label cranelift on PR #14652.
Wasmtime GitHub notifications bot (Oct 10 2026 at 04:51):github-actions[bot] added the label cranelift:area:x64 on PR #14652.
Wasmtime GitHub notifications bot (Oct 10 2026 at 06:14)::check: alexcrichton merged PR #14652.
Wasmtime GitHub notifications bot (Oct 10 2026 at 06:14):alexcrichton removed PR #14652 Cranelift: x64: fix i128 shift amounts in several lowering rules. from the merge queue
Last updated: Oct 11 2026 at 04:10 UTC