[MicroPerf] Inline TryD to remove constraint-solver closure allocations - #20367
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[MicroPerf] Inline TryD to remove constraint-solver closure allocations#20367T-Gro wants to merge 3 commits into
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Make `TryD` inline with `[<InlineIfLambda>]` on the always-evaluated `f` argument so the `f`/`g` lambda closures are no longer allocated at each call site (hottest: SolveTypeEqualsType via SolveTypeEqualsTypeKeepAbbrevsWithCxsln). `IgnoreFailedMemberConstraintResolution` is made inline so its non-literal `f1` propagates as a lambda, keeping InlineIfLambda satisfied without FS3517. Pure inline refactor: byte-identical compiler output (deterministic self-compile SHA-256 match); no behavior change. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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TryDis nowinlinewith[<InlineIfLambda>]on its always-runf, so the argument closures are no longer allocated at the constraint-solver call sites;IgnoreFailedMemberConstraintResolutionisinlineso its forwardedf1stays a literal.Sampled GC closure allocation at the hottest site (
SolveTypeEqualsTypeviaSolveTypeEqualsTypeKeepAbbrevsWithCxsln), compiling a 120-file set — ~412 MB removed:flambda (@1514)glambda (@1515)Cost is negligible:
FSharp.Compiler.Service.dllgrows +1.5 KB (+0.007%) from the inlined expansions. Pure inline refactor —--deterministic+self-compile is byte-identical (SHA-256 match), no behavior change.Zset.iter/Zmap.iterwere evaluated and left unchanged — they only pass the lambda to a non-inline recursive tree-walker, so[<InlineIfLambda>]cannot remove the closure.