Wasmtime GitHub notifications bot (Mar 18 2026 at 04:54): Wasmtime GitHub notifications bot (Mar 18 2026 at 04:54):alexcrichton opened PR #12798 from alexcrichton:csdb-optional to bytecodealliance:main:
Make this instruction's emission conditional based on
enable_table_access_spectre_mitigationwhich is a rough equivalent in terms of preexisting Cranelift settings. In #12789 it's shown that this instruction has a very large performance impact on macOS aarch64 at least, and currently there's no way to turn this off even for testing. The goal of this commit is to at least not tamper with defaults while providing an escape hatch. This notably doesn't fix #12789 because this is such an obscure option I'd personally say the true thing to resolve is the default behavior, not knobs.<!--
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Wasmtime GitHub notifications bot (Mar 18 2026 at 04:54):alexcrichton requested cfallin for a review on PR #12798.
Wasmtime GitHub notifications bot (Mar 18 2026 at 04:54):alexcrichton requested wasmtime-compiler-reviewers for a review on PR #12798.
Wasmtime GitHub notifications bot (Mar 18 2026 at 07:58):github-actions[bot] added the label cranelift on PR #12798.
Wasmtime GitHub notifications bot (Mar 18 2026 at 07:58):github-actions[bot] added the label cranelift:area:aarch64 on PR #12798.
Wasmtime GitHub notifications bot (Mar 18 2026 at 09:33):cfallin submitted PR review.
Wasmtime GitHub notifications bot (Mar 18 2026 at 09:33):cfallin added PR #12798 aarch64: Make csdb in JTSequence conditional to the merge queue.
Wasmtime GitHub notifications bot (Mar 18 2026 at 09:57):cfallin merged PR #12798.
Wasmtime GitHub notifications bot (Mar 18 2026 at 09:57):cfallin removed PR #12798 aarch64: Make csdb in JTSequence conditional from the merge queue.
Last updated: Mar 23 2026 at 16:19 UTC