Wasmtime GitHub notifications bot (Sep 01 2026 at 15:54): Wasmtime GitHub notifications bot (Sep 01 2026 at 15:54):alexcrichton opened PR #14259 from alexcrichton:box-compiler-context to bytecodealliance:main:
This commit moves an intermediate data structure Wasmtime uses when compiling functions onto the heap instead of being inline. This structure is moved around a fair bit as it's reused between compiling functions and will round-trip through an internal cache that the compilation phases uses. The structure itself is kilobytes large meaning that each movement cost a fair bit of time, so by boxing it is moving around far less data.
Locally on a module with 100k empty functions this improves compile time by ~20%.
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Wasmtime GitHub notifications bot (Sep 01 2026 at 15:54):alexcrichton requested cfallin for a review on PR #14259.
Wasmtime GitHub notifications bot (Sep 01 2026 at 15:54):alexcrichton requested wasmtime-compiler-reviewers for a review on PR #14259.
Wasmtime GitHub notifications bot (Sep 01 2026 at 15:58)::thumbs_up: cfallin submitted PR review:
Nice speedup!
Wasmtime GitHub notifications bot (Sep 01 2026 at 15:58):cfallin has enabled auto merge for PR #14259.
Wasmtime GitHub notifications bot (Sep 01 2026 at 16:03):cfallin added PR #14259 Move CompilerContext onto the heap to the merge queue.
Wasmtime GitHub notifications bot (Sep 01 2026 at 16:27)::check: cfallin merged PR #14259.
Wasmtime GitHub notifications bot (Sep 01 2026 at 16:27):cfallin removed PR #14259 Move CompilerContext onto the heap from the merge queue.
Last updated: Sep 20 2026 at 18:08 UTC