perf(semantic): use direct grandparent lookup for TS type parameters by camc314 · Pull Request #22658 · oxc-project/oxc

camc314 · 2026-05-21T19:40:31Z

check_ts_type_parameter validates in / out variance modifiers by checking the node that owns the surrounding TSTypeParameterDeclaration.

The parent of a TSTypeParameter is always the TSTypeParameterDeclaration, so this replaces ancestor_kinds(...).nth(1) with direct parent_id / parent_kind access. That avoids constructing and advancing the ancestor iterator when the grandparent node is the only value needed.

note: no performance improvement is expected here as we do not test this path in the benchmarks

camc314 · 2026-05-21T19:40:45Z

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Pull request overview

Optimizes TypeScript semantic checking for in/out variance modifiers on TSTypeParameter by replacing an ancestor-iterator traversal with direct parent/grandparent lookup via parent_id/parent_kind, reducing overhead in a hot checker path.

Changes:

Replace ancestor_kinds(...).nth(1) with parent_kind(parent_id(...)) to directly access the owning node of a TSTypeParameterDeclaration.
Keep the same allowed-owner set (TSInterfaceDeclaration, Class, TSTypeAliasDeclaration) while avoiding iterator construction/advancement.

codspeed-hq · 2026-05-21T19:49:10Z

Merging this PR will not alter performance

✅ 57 untouched benchmarks
⏩ 3 skipped benchmarks¹

_{Comparing c/05-21-perf_semantic_use_direct_grandparent_lookup_for_ts_type_parameters (37ab523) with c/05-21-perf_semantic_reorder_numeric_literal_strict_mode_checks (dbd2127)}

3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

Dunqing · 2026-05-22T00:51:52Z

Merge activity

May 22, 12:51 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
May 22, 4:20 AM UTC: Dunqing added this pull request to the Graphite merge queue.
May 22, 4:28 AM UTC: Merged by the Graphite merge queue.

…22658) `check_ts_type_parameter` validates `in` / `out` variance modifiers by checking the node that owns the surrounding `TSTypeParameterDeclaration`. The parent of a `TSTypeParameter` is always the `TSTypeParameterDeclaration`, so this replaces `ancestor_kinds(...).nth(1)` with direct `parent_id` / `parent_kind` access. That avoids constructing and advancing the ancestor iterator when the grandparent node is the only value needed. note: no performance improvement is expected here as we do not test this path in the benchmarks

### 🚀 Features - e857b0c napi/minify: Expose legalComments option and result (#20370) (Boshen) - 661132d parser: More friendly error messages for rest assignment target and rest binding element (#22719) (sapphi-red) - ee659b6 transformer/legacy-decorator: Add `strictNullChecks` option for nullable-union design:type (#22266) (Kyle Cannon) ### 🐛 Bug Fixes - e1d064e transformer/class-properties: Reparent lifted private method helpers (#22716) (Cameron) - 4ac0fca minifier: Preserve `0 && (module.exports = { ... })` cjs-module-lexer hint (#22729) (Dunqing) - 40ff611 minifier: Mark peephole loop changed when dropping dead-after-throw statement (#22722) (Dunqing) - 2f7b210 codegen: Emit pife-arrow/function leading comments inside the wrap (#22720) (Dunqing) - e184f74 parser: Improve invalid `import` property access diagnostic (#22693) (camc314) - 7baed9c transformer/private-method: Clear inherited strict flags (#22508) (camc314) - a9ad27e parser: Keep annotation comments leading without preceding newline (#22711) (Dunqing) - 9ea4d64 minifier: Re-evaluate pure/no-side-effects flags after peephole inlining (#22595) (Dunqing) - 07afbb6 minifier: Drop empty-body IIFE wrapper when called with arguments (#22589) (Dunqing) - fa7c463 semantic: Correct TS enum member symbol spans (#22689) (camc314) - 26b9396 semantic: Resolve parameter decorators outside parameter scope (#22623) (camc314) - b284045 parser: Switch to module goal eagerly on `export` (#22684) (Boshen) - dfa931d semantic: Propagate unresolved auto-increment enum value instead of defaulting to 0 (#22646) (Dunqing) - 69a6ba6 transformer/legacy-decorator: Emit Array for ReadonlyArray<T> in decorator metadata (#22265) (Kyle Cannon) - e421ef0 transformer/legacy-decorator: Return runtime binding for design:type (#22640) (Dunqing) - d61e1d7 codegen: Preserve verbatim text of pure/no-side-effects comments (#22525) (Dunqing) - 702b14e minifier: Preserve IIFE structure in DCE-only mode (#22547) (Dunqing) - 917da24 parser: Apply PURE comment through member-access chains (#22566) (Dunqing) - a069b1c codegen: Preserve quotes for cjs-module-lexer equality strings (#22551) (Dunqing) ### ⚡ Performance - 2f623b0 semantic: Skip unresolved checks for re-exports (#22660) (camc314) - 0d9553d semantic: Early-exit `check_object_expression` for objects with <2 properties (#22668) (Dunqing) - d721ad9 semantic: Use direct grandparent lookup for TS type parameters (#22658) (camc314) - 0aff288 semantic: Reorder numeric literal strict mode checks (#22657) (camc314) - 4d5ddb1 semantic: Reorder binding identifier checks (#22656) (camc314) - e32acd8 semantic: Reorder identifier ambient binding check (#22653) (camc314) - 09fe178 semantic: Reorder ident reference strict mode check (#22652) (camc314) - 4b6add2 semantic: Avoid duplicate ident clone for bindings (#22663) (camc314) - 82f9662 parser: Check identifier kind before context flag (#22662) (camc314) - d7cd951 parser: Fast path identifier parsing and inline operator helpers (#22650) (Boshen) - 7b84314 semantic: Use direct byte access for numeric leading-zero check (#22642) (camc314) - 0345a31 semantic: Pre-size class elements hash map (#22618) (camc314) - 04d3065 minifier: Drop per-call buffers in try_fold_concat (#22596) (Dunqing) - 4f289f1 semantic: Resolve_references_for_current_scope without a temp Vec (#22599) (Dunqing) - e862c15 semantic: Avoid heap alloc for var hoist scope ids (#22603) (Dunqing) - 8ff8674 semantic: Early return if `excess` is `0` in `Stats::increase_by` (#22616) (camc314) - 7a4120e semantic: Pre-reserve unresolved_references using Stats::references (#22580) (Dunqing) Co-authored-by: Dunqing <[email protected]>

github-actions Bot added the A-semantic Area - Semantic label May 21, 2026

camc314 marked this pull request as ready for review May 21, 2026 19:41

camc314 requested a review from Dunqing as a code owner May 21, 2026 19:41

Copilot AI review requested due to automatic review settings May 21, 2026 19:41

Copilot started reviewing on behalf of camc314 May 21, 2026 19:41 View session

Copilot AI reviewed May 21, 2026

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This was referenced May 21, 2026

perf(semantic): store class parents in IndexVec #22659

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perf(semantic): skip unresolved checks for re-exports #22660

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Dunqing approved these changes May 22, 2026

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Dunqing added the 0-merge Merge with Graphite Merge Queue label May 22, 2026

graphite-app Bot force-pushed the c/05-21-perf_semantic_reorder_numeric_literal_strict_mode_checks branch from dbd2127 to acf6844 Compare May 22, 2026 00:56

graphite-app Bot force-pushed the c/05-21-perf_semantic_use_direct_grandparent_lookup_for_ts_type_parameters branch from 37ab523 to 0c22389 Compare May 22, 2026 00:57

graphite-app Bot force-pushed the c/05-21-perf_semantic_reorder_numeric_literal_strict_mode_checks branch from acf6844 to 0aff288 Compare May 22, 2026 04:22

graphite-app Bot force-pushed the c/05-21-perf_semantic_use_direct_grandparent_lookup_for_ts_type_parameters branch from 0c22389 to d721ad9 Compare May 22, 2026 04:22

graphite-app Bot removed the 0-merge Merge with Graphite Merge Queue label May 22, 2026

Base automatically changed from c/05-21-perf_semantic_reorder_numeric_literal_strict_mode_checks to main May 22, 2026 04:27

graphite-app Bot merged commit d721ad9 into main May 22, 2026
31 checks passed

graphite-app Bot deleted the c/05-21-perf_semantic_use_direct_grandparent_lookup_for_ts_type_parameters branch May 22, 2026 04:28

oxc-guard Bot mentioned this pull request May 26, 2026

release(crates): oxc v0.133.0 #22734

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perf(semantic): use direct grandparent lookup for TS type parameters#22658

perf(semantic): use direct grandparent lookup for TS type parameters#22658
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camc314 commented May 21, 2026 •

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Pull request overview

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codspeed-hq Bot commented May 21, 2026

Merging this PR will not alter performance

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camc314 commented May 21, 2026 •

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