Split shallow_resolve into an inlinable fast path [-0.10% avg] - #103
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xmakro wants to merge 1 commit into
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Split shallow_resolve into an inlinable fast path [-0.10% avg]#103xmakro wants to merge 1 commit into
xmakro wants to merge 1 commit into
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The overwhelmingly common case is a type that is not an inference variable, which can be answered by looking at the kind. Keep that path tiny and inlinable at the many cross-crate call sites and push variable resolution into a separate never-inlined function.
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The overwhelmingly common case is a type that is not an inference variable, which can be answered by looking at the type kind. Keep that path tiny and inlinable at the many cross-crate call sites and push the actual variable resolution into a separate never-inlined function.
Measured alone at head 969b803 (clean from-scratch ThinLTO plus jemalloc stage2 build per side, instructions:u, Check/Debug/Opt across Full/IncrFull/IncrUnchanged/IncrPatched, 551 cells): -0.10% mean, 70 cells improved by at least 0.25%, 1 regressed. Top cells: projection-caching check full -1.13%, deeply-nested-multi check full -0.90%, unify-linearly check full -0.81%.
Caveat: this is an inlining change rather than work removal, and the local proxy has no PGO or BOLT, so the collector may credit inlining that a dist build would already have done. Expect the upstream number to come in under the local one.