perf(transformer_plugins): switch ReplaceGlobalDefines from Traverse to VisitMut by Boshen · Pull Request #19146 · oxc-project/oxc

Boshen · 2026-02-08T14:43:46Z

Summary

Replace the heavy Traverse infrastructure with the lighter VisitMut visitor for ReplaceGlobalDefines, eliminating ~300 parent stack push/pop operations and ~136 scope tracking operations per AST walk
Store Scoping directly on the struct, track function depth for this replacement scope flags, and collect destructuring keys in visit_variable_declarator instead of using the Ancestor stack
Update is_dot_define signature to take &Scoping, ScopeFlags parameters, and update InjectGlobalVariables call site accordingly

Closes oxc-project/backlog#189 (for ReplaceGlobalDefines; InjectGlobalVariables migration can follow separately)

🤖 Generated with Claude Code

Copilot

Pull request overview

This PR migrates the ReplaceGlobalDefines transformer plugin from the heavier Traverse infrastructure to a VisitMut-based walk to reduce per-AST-walk overhead, while updating related call sites.

Changes:

Replaces Traverse traversal with VisitMut for ReplaceGlobalDefines, storing Scoping on the visitor and adding local state to support prior optimizations.
Updates dot-define matching to take &Scoping and ScopeFlags (instead of TraverseCtx) and adjusts InjectGlobalVariables accordingly.
Refactors destructuring optimization to collect destructuring keys during visit_variable_declarator (instead of relying on an ancestor stack).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
`crates/oxc_transformer_plugins/src/replace_global_defines.rs`	Switches to `VisitMut`, adds scoping/state tracking, and refactors replacement + destructuring optimization logic.
`crates/oxc_transformer_plugins/src/inject_global_variables.rs`	Updates `is_dot_define` call site to pass `&Scoping` and `ScopeFlags`.

Comments suppressed due to low confidence (1)

crates/oxc_transformer_plugins/src/replace_global_defines.rs:875

UpdateReplacedExpression assigns new identifier references to root_scope_id(). Previously references were created in the current scope, which is important for correct resolution/shadowing and for downstream passes (e.g. DCE) that rely on reference.scope_id(). Please track the current scope id during the VisitMut walk (e.g. via enter_scope/leave_scope) and use that scope id when creating References for parsed replacement expressions.

crates/oxc_transformer_plugins/src/replace_global_defines.rs

codspeed-hq · 2026-02-08T14:50:33Z

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing perf/replace-global-defines-visit-mut (e1c16e4) with main (cc6cf88)}

Summary

✅ 47 untouched benchmarks
⏩ 3 skipped benchmarks¹

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. ↩

Boshen · 2026-02-08T16:10:42Z

Merge activity

Feb 8, 4:10 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
Feb 8, 4:10 PM UTC: Boshen added this pull request to the Graphite merge queue.
Feb 8, 4:17 PM UTC: Merged by the Graphite merge queue.

…to VisitMut (#19146) ## Summary - Replace the heavy `Traverse` infrastructure with the lighter `VisitMut` visitor for `ReplaceGlobalDefines`, eliminating ~300 parent stack push/pop operations and ~136 scope tracking operations per AST walk - Store `Scoping` directly on the struct, track function depth for `this` replacement scope flags, and collect destructuring keys in `visit_variable_declarator` instead of using the Ancestor stack - Update `is_dot_define` signature to take `&Scoping, ScopeFlags` parameters, and update `InjectGlobalVariables` call site accordingly Closes oxc-project/backlog#189 (for `ReplaceGlobalDefines`; `InjectGlobalVariables` migration can follow separately) 🤖 Generated with [Claude Code](https://claude.com/claude-code)

Dunqing · 2026-02-09T13:55:28Z

I just took a brief look at this PR, and I found that ReplaceGlobalDefines still requires the caller to pass a scoping in it. This is incomplete, as the purpose of oxc-project/backlog#189 is to remove the scoping needed so that Rolldown could reduce building scoping once. Switch Traverse to VisitMut is the prerequisite.

### 💥 BREAKING CHANGES - 2bf7293 mangler: [**BREAKING**] Enable `top_level` by default for modules and commonjs (#18278) (sapphi-red) - 48b0542 span: [**BREAKING**] SourceType::ts should set module to unambigious (#18873) (Boshen) ### 🚀 Features - 500d071 minifier: Local traverse ctx and generated minifier traverse (#19106) (Boshen) - 142a1be parser: Detect binary files with TS1490 error (#19047) (Boshen) - e316857 allocator/bitset: Add `Ones` iterator to `BitSet` (#19027) (sapphi-red) - 742ad3f minifier: Default `invalid_import_side_effects` to `false` (#18916) (sapphi-red) - 0eff6be parser: Error JSX-like type assertions and generics in `.mts`/`.cts` (#18910) (Boshen) - 18320c6 span: Store file extension in `SourceType` (#18893) (Boshen) ### 🐛 Bug Fixes - a7514e4 isolated-declarations: Preserve const context in literal type inference (#19178) (camc314) - 312e756 isolated-declarations: Preserve readonly literal initializers (#19177) (camc314) - d0ca8d0 isolated-declarations: Skip parenthesis when inferring type (#19176) (camc314) - 110c300 oxc_ecmascript: `+[false]` and `+[true]` should evaluate to `NaN` (#19174) (copilot-swe-agent) - f32ea19 semantic: Report redeclaration error for import bindings conflicting with value declarations (#19068) (Boshen) - 3aeba7a semantic: Report redeclaration error for `function a() {} var a` in module mode (#19041) (Boshen) - 35e32c6 coverage: Match Babel's options.json inheritance for test fixtures (#19002) (Boshen) - 463d60d semantic: Skip TS2391 for standalone computed-name class methods (#19025) (Boshen) - 56c086b parser: Add modifier ordering validation (TS1029) (#19024) (Boshen) - 6067a49 linter/jsdoc: False positive in `check-tag-names` for `@` in email addresses and npm scopes (#19021) (Boshen) - b13bb70 semantic/jsdoc: Inline tags like `{@link}` break jsdoc parsing (#19019) (Boshen) - e3609e3 regular_expression: Preserve UnicodeEscape CharacterKind in string literals (#18998) (Boshen) - 57917ee parser: Parse decorators on rest parameters (#18938) (Boshen) - 487601b napi: Disable mimalloc on Windows to fix worker_threads crash (#18923) (Boshen) - 1f6b193 parser: Validate TypeScript import type options (#18889) (Boshen) - 1663184 parser: Allow conditional types in function type parameters (#18886) (Boshen) - 5758046 parser: Error on property access after instantiation expression (#18887) (Boshen) - 5eb4a94 parser: Handle `<<` as two `<` tokens in type argument contexts (#18885) (Boshen) ### ⚡ Performance - ed8c054 oxc_str: Add precomputed hash to Ident for fast HashMap lookups (#19143) (Boshen) - d4a0867 transformer_plugins: Switch ReplaceGlobalDefines from Traverse to VisitMut (#19146) (Boshen) - 9eb16b3 syntax: Pack ASCII identifier tables into single bitflag table (#19088) (Boshen) - e7595d1 mangler: Use BitSet for exported symbols set (#19023) (sapphi-red) - 2537924 semantic: Optimize scope resolution with fast paths and inlining (#19029) (Boshen) - 69a8d85 mangler: Use BitSet for keep_names symbols set (#19028) (sapphi-red) - f78c525 parser: Try hybrid parsing for jsx children and closing element/fragments (#18789) (camchenry) Co-authored-by: camc314 <[email protected]>

### 💥 BREAKING CHANGES - 2bf7293 mangler: [**BREAKING**] Enable `top_level` by default for modules and commonjs (oxc-project#18278) (sapphi-red) - 48b0542 span: [**BREAKING**] SourceType::ts should set module to unambigious (oxc-project#18873) (Boshen) ### 🚀 Features - 500d071 minifier: Local traverse ctx and generated minifier traverse (oxc-project#19106) (Boshen) - 142a1be parser: Detect binary files with TS1490 error (oxc-project#19047) (Boshen) - e316857 allocator/bitset: Add `Ones` iterator to `BitSet` (oxc-project#19027) (sapphi-red) - 742ad3f minifier: Default `invalid_import_side_effects` to `false` (oxc-project#18916) (sapphi-red) - 0eff6be parser: Error JSX-like type assertions and generics in `.mts`/`.cts` (oxc-project#18910) (Boshen) - 18320c6 span: Store file extension in `SourceType` (oxc-project#18893) (Boshen) ### 🐛 Bug Fixes - a7514e4 isolated-declarations: Preserve const context in literal type inference (oxc-project#19178) (camc314) - 312e756 isolated-declarations: Preserve readonly literal initializers (oxc-project#19177) (camc314) - d0ca8d0 isolated-declarations: Skip parenthesis when inferring type (oxc-project#19176) (camc314) - 110c300 oxc_ecmascript: `+[false]` and `+[true]` should evaluate to `NaN` (oxc-project#19174) (copilot-swe-agent) - f32ea19 semantic: Report redeclaration error for import bindings conflicting with value declarations (oxc-project#19068) (Boshen) - 3aeba7a semantic: Report redeclaration error for `function a() {} var a` in module mode (oxc-project#19041) (Boshen) - 35e32c6 coverage: Match Babel's options.json inheritance for test fixtures (oxc-project#19002) (Boshen) - 463d60d semantic: Skip TS2391 for standalone computed-name class methods (oxc-project#19025) (Boshen) - 56c086b parser: Add modifier ordering validation (TS1029) (oxc-project#19024) (Boshen) - 6067a49 linter/jsdoc: False positive in `check-tag-names` for `@` in email addresses and npm scopes (oxc-project#19021) (Boshen) - b13bb70 semantic/jsdoc: Inline tags like `{@link}` break jsdoc parsing (oxc-project#19019) (Boshen) - e3609e3 regular_expression: Preserve UnicodeEscape CharacterKind in string literals (oxc-project#18998) (Boshen) - 57917ee parser: Parse decorators on rest parameters (oxc-project#18938) (Boshen) - 487601b napi: Disable mimalloc on Windows to fix worker_threads crash (oxc-project#18923) (Boshen) - 1f6b193 parser: Validate TypeScript import type options (oxc-project#18889) (Boshen) - 1663184 parser: Allow conditional types in function type parameters (oxc-project#18886) (Boshen) - 5758046 parser: Error on property access after instantiation expression (oxc-project#18887) (Boshen) - 5eb4a94 parser: Handle `<<` as two `<` tokens in type argument contexts (oxc-project#18885) (Boshen) ### ⚡ Performance - ed8c054 oxc_str: Add precomputed hash to Ident for fast HashMap lookups (oxc-project#19143) (Boshen) - d4a0867 transformer_plugins: Switch ReplaceGlobalDefines from Traverse to VisitMut (oxc-project#19146) (Boshen) - 9eb16b3 syntax: Pack ASCII identifier tables into single bitflag table (oxc-project#19088) (Boshen) - e7595d1 mangler: Use BitSet for exported symbols set (oxc-project#19023) (sapphi-red) - 2537924 semantic: Optimize scope resolution with fast paths and inlining (oxc-project#19029) (Boshen) - 69a8d85 mangler: Use BitSet for keep_names symbols set (oxc-project#19028) (sapphi-red) - f78c525 parser: Try hybrid parsing for jsx children and closing element/fragments (oxc-project#18789) (camchenry) Co-authored-by: camc314 <[email protected]>

…to VisitMut (oxc-project#19146) ## Summary - Replace the heavy `Traverse` infrastructure with the lighter `VisitMut` visitor for `ReplaceGlobalDefines`, eliminating ~300 parent stack push/pop operations and ~136 scope tracking operations per AST walk - Store `Scoping` directly on the struct, track function depth for `this` replacement scope flags, and collect destructuring keys in `visit_variable_declarator` instead of using the Ancestor stack - Update `is_dot_define` signature to take `&Scoping, ScopeFlags` parameters, and update `InjectGlobalVariables` call site accordingly Closes oxc-project/backlog#189 (for `ReplaceGlobalDefines`; `InjectGlobalVariables` migration can follow separately) 🤖 Generated with [Claude Code](https://claude.com/claude-code)

### 💥 BREAKING CHANGES - 2bf7293 mangler: [**BREAKING**] Enable `top_level` by default for modules and commonjs (oxc-project#18278) (sapphi-red) - 48b0542 span: [**BREAKING**] SourceType::ts should set module to unambigious (oxc-project#18873) (Boshen) ### 🚀 Features - 500d071 minifier: Local traverse ctx and generated minifier traverse (oxc-project#19106) (Boshen) - 142a1be parser: Detect binary files with TS1490 error (oxc-project#19047) (Boshen) - e316857 allocator/bitset: Add `Ones` iterator to `BitSet` (oxc-project#19027) (sapphi-red) - 742ad3f minifier: Default `invalid_import_side_effects` to `false` (oxc-project#18916) (sapphi-red) - 0eff6be parser: Error JSX-like type assertions and generics in `.mts`/`.cts` (oxc-project#18910) (Boshen) - 18320c6 span: Store file extension in `SourceType` (oxc-project#18893) (Boshen) ### 🐛 Bug Fixes - a7514e4 isolated-declarations: Preserve const context in literal type inference (oxc-project#19178) (camc314) - 312e756 isolated-declarations: Preserve readonly literal initializers (oxc-project#19177) (camc314) - d0ca8d0 isolated-declarations: Skip parenthesis when inferring type (oxc-project#19176) (camc314) - 110c300 oxc_ecmascript: `+[false]` and `+[true]` should evaluate to `NaN` (oxc-project#19174) (copilot-swe-agent) - f32ea19 semantic: Report redeclaration error for import bindings conflicting with value declarations (oxc-project#19068) (Boshen) - 3aeba7a semantic: Report redeclaration error for `function a() {} var a` in module mode (oxc-project#19041) (Boshen) - 35e32c6 coverage: Match Babel's options.json inheritance for test fixtures (oxc-project#19002) (Boshen) - 463d60d semantic: Skip TS2391 for standalone computed-name class methods (oxc-project#19025) (Boshen) - 56c086b parser: Add modifier ordering validation (TS1029) (oxc-project#19024) (Boshen) - 6067a49 linter/jsdoc: False positive in `check-tag-names` for `@` in email addresses and npm scopes (oxc-project#19021) (Boshen) - b13bb70 semantic/jsdoc: Inline tags like `{@link}` break jsdoc parsing (oxc-project#19019) (Boshen) - e3609e3 regular_expression: Preserve UnicodeEscape CharacterKind in string literals (oxc-project#18998) (Boshen) - 57917ee parser: Parse decorators on rest parameters (oxc-project#18938) (Boshen) - 487601b napi: Disable mimalloc on Windows to fix worker_threads crash (oxc-project#18923) (Boshen) - 1f6b193 parser: Validate TypeScript import type options (oxc-project#18889) (Boshen) - 1663184 parser: Allow conditional types in function type parameters (oxc-project#18886) (Boshen) - 5758046 parser: Error on property access after instantiation expression (oxc-project#18887) (Boshen) - 5eb4a94 parser: Handle `<<` as two `<` tokens in type argument contexts (oxc-project#18885) (Boshen) ### ⚡ Performance - ed8c054 oxc_str: Add precomputed hash to Ident for fast HashMap lookups (oxc-project#19143) (Boshen) - d4a0867 transformer_plugins: Switch ReplaceGlobalDefines from Traverse to VisitMut (oxc-project#19146) (Boshen) - 9eb16b3 syntax: Pack ASCII identifier tables into single bitflag table (oxc-project#19088) (Boshen) - e7595d1 mangler: Use BitSet for exported symbols set (oxc-project#19023) (sapphi-red) - 2537924 semantic: Optimize scope resolution with fast paths and inlining (oxc-project#19029) (Boshen) - 69a8d85 mangler: Use BitSet for keep_names symbols set (oxc-project#19028) (sapphi-red) - f78c525 parser: Try hybrid parsing for jsx children and closing element/fragments (oxc-project#18789) (camchenry) Co-authored-by: camc314 <[email protected]>

Boshen requested review from Dunqing and overlookmotel as code owners February 8, 2026 14:43

Copilot AI review requested due to automatic review settings February 8, 2026 14:43

github-actions bot added the C-performance Category - Solution not expected to change functional behavior, only performance label Feb 8, 2026

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Boshen force-pushed the perf/replace-global-defines-visit-mut branch from 1d0c073 to e1c16e4 Compare February 8, 2026 15:45

Boshen added the 0-merge Merge with Graphite Merge Queue label Feb 8, 2026

graphite-app bot force-pushed the perf/replace-global-defines-visit-mut branch from e1c16e4 to d4a0867 Compare February 8, 2026 16:11

graphite-app bot merged commit d4a0867 into main Feb 8, 2026
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Boshen mentioned this pull request Feb 9, 2026

release(crates): oxc v0.113.0 #19167

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Dunqing mentioned this pull request Feb 10, 2026

refactor(transformer_plugins): migrate InjectGlobalVariables from Traverse to VisitMut #19195

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Boshen mentioned this pull request Feb 10, 2026

release(crates): oxc v0.113.0 #19210

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release(crates): oxc v0.113.0 #19215

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perf(transformer_plugins): switch ReplaceGlobalDefines from Traverse to VisitMut#19146

perf(transformer_plugins): switch ReplaceGlobalDefines from Traverse to VisitMut#19146
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