perf(jsdoc): skip should_attach_jsdoc when no remaining comments#22409
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) ## Summary `JSDocBuilder::retrieve_attached_jsdoc` is called for every AST node during the semantic build. Even when the source contains no JSDoc comments, the per-node `should_attach_jsdoc(kind)` `matches!` over 33 variants still runs. This adds a fast-path early return when `not_attached_docs` is empty — true for files with no JSDoc, and for the tail of every walk once all comments have been attached — and marks `retrieve_attached_jsdoc` `#[inline]` so the guard fuses into `SemanticBuilder::create_ast_node`. ## Measurements `xcrun xctrace record --template 'Time Profiler'`, semantic stage on the standard benchmark inputs. Profile binary built with `--profile release-with-debug`. `retrieve_attached_jsdoc` self-time: | file | before | after | |---|---|---| | antd.js (6.7M, sparse JSDoc) | 2.59% | **0.04%** | | checker.ts (2.8M, JSDoc throughout) | 3.23% | **0.17%** | Hot-path bundle (retrieve + should_attach + create_ast_node) drops ~2pp on both files. Wall-time on 50 iters of parse+semantic: antd −9%, checker −8%, cal.com.tsx −5%. ## Notes - `should_attach_jsdoc` still runs when there are comments left to attach, so behavior is unchanged. - The `#[inline]` lets LLVM fuse the empty-map check into the visitor body, which is what amplifies the win on JSDoc-heavy inputs (the guard fires once all comments are placed). 🤖 Generated with [Claude Code](https://claude.com/claude-code)
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### 🐛 Bug Fixes - 0f26de6 ecmascript: Resolve identifier value type via tracked constants (#22234) (Alexander Lichter) - c27a8cf minifier: Normalize `{ x: x }` shorthand so adjacent-if merge is idempotent (#22401) (Dunqing) - e431a0e parser: Break extends clause loop on fatal error (#22517) (Boshen) - e9ec7c6 minifier: Fold optional chains by base nullishness (#22236) (Alexander Lichter) - e6090e7 transformer: Keep enum IIFE when a non-inlinable value reference remains (#22501) (Dunqing) - 931b7d6 transformer: Inline const enum members through type-cast wrappers (#22500) (Dunqing) - b9615b2 codegen: Preserve string quotes in require() calls during minification (#22475) (zennnnnnn11) - c73c159 transformer/async-to-generator: Reparent parameter initializer scopes (#22507) (camc314) - ecfd3ca transformer/async-to-generator: Move only parameter bindings (#22503) (camc314) - 3ce3431 transformer/explicit-resource-managment: Preserve shadowed for-head block (#22451) (camc314) ### ⚡ Performance - ce92c6c semantic: `#[inline]` `Scoping::get_binding` (#22414) (Dunqing) - 98be95c regular_expression: Track regex flags via bitflags (#22427) (Boshen) - dbbc059 jsdoc: Skip should_attach_jsdoc when no remaining comments (#22409) (Boshen) - 217d7d8 minifier: Index `SymbolValues` by `SymbolId` (#22441) (Dunqing) - d782b78 minifier: Use BitSet for LiveUsageCollector live references (#22425) (Boshen)
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Summary
JSDocBuilder::retrieve_attached_jsdocis called for every AST node during the semantic build. Even when the source contains no JSDoc comments, the per-nodeshould_attach_jsdoc(kind)matches!over 33 variants still runs.This adds a fast-path early return when
not_attached_docsis empty — true for files with no JSDoc, and for the tail of every walk once all comments have been attached — and marksretrieve_attached_jsdoc#[inline]so the guard fuses intoSemanticBuilder::create_ast_node.Measurements
xcrun xctrace record --template 'Time Profiler', semantic stage on the standard benchmark inputs. Profile binary built with--profile release-with-debug.retrieve_attached_jsdocself-time:Hot-path bundle (retrieve + should_attach + create_ast_node) drops ~2pp on both files. Wall-time on 50 iters of parse+semantic: antd −9%, checker −8%, cal.com.tsx −5%.
Notes
should_attach_jsdocstill runs when there are comments left to attach, so behavior is unchanged.#[inline]lets LLVM fuse the empty-map check into the visitor body, which is what amplifies the win on JSDoc-heavy inputs (the guard fires once all comments are placed).🤖 Generated with Claude Code