perf(renamer): dedup before allocating the owned name in add_symbol_in_root_scope#9740
Merged
Merged
Conversation
✅ Deploy Preview for rolldown-rs canceled.
|
Merging this PR will not alter performance
Comparing 
Footnotes
|
IWANABETHATGUY
approved these changes
Jun 14, 2026
Contributor
Merge activity
|
…n_root_scope (#9740) ## Summary In the `Renamer::add_symbol_in_root_scope` deconflict path, an owned `original_name` (`CompactStr`) was built *before* the `canonical_names.contains_key(&canonical_ref)` dedup check. On apps/10000, ~19,870 of ~59,943 calls are re-adds of an already-present `canonical_ref` (31.7%) — every one of those built and then discarded the owned name. This hoists the dedup check above the name construction so an already-present `canonical_ref` returns before the `CompactStr` allocation. It's guarded by `needs_deconflict` to preserve the original control flow exactly: the old unguarded check was only reachable on the `needs_deconflict` path (the `!needs_deconflict` branch returns earlier, and still needs the built name to insert). ## Correctness Behavior-preserving and **byte-identical** (`main.js` + `main.js.map` sha256 match baseline on apps/10000). Verified by cases: - `!needs_deconflict` → unchanged: builds the name and inserts (the new guard is skipped). - `needs_deconflict` + already present → returns without state change (only difference vs before: the wasted name-build is skipped). - `needs_deconflict` + not present → falls through to the same fast/slow path. ## Performance Removes ~19,870 wasted `CompactStr` builds per build. (Note: the deconflict path's remaining cost is genuine — ~66.7% of symbols on this workload really do collide and need renaming; this PR only removes the pre-dedup waste, nothing structural.) Local wall is within ambient noise; relying on **CodSpeed** for the clean number. `+8 / -4`, one file. fmt/clippy clean. 🤖 Generated with [Claude Code](https://claude.com/claude-code) <!-- CURSOR_SUMMARY --> --- > [!NOTE] > **Low Risk** > Behavior-preserving reorder of an existing early return; only affects performance on the chunk symbol deconflict hot path, not naming semantics. > > **Overview** > **`Renamer::add_symbol_in_root_scope`** now returns early on duplicate `canonical_ref` entries *before* constructing the owned `original_name` (`CompactStr`), but only when `needs_deconflict` is true. > > The `!needs_deconflict` path is unchanged: it still builds the name and inserts. On large bundles, many deconflict calls are no-op re-adds; skipping the JSX-capitalization and `CompactStr` work on those calls removes redundant allocations without changing rename results. > > <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit 08280d5. Bugbot is set up for automated code reviews on this repo. Configure [here](https://www.cursor.com/dashboard/bugbot).</sup> <!-- /CURSOR_SUMMARY -->
08280d5 to
0f0e287
Compare
shulaoda
added a commit
that referenced
this pull request
Jun 18, 2026
## [1.1.2] - 2026-06-18 ### 📝 Notable tsconfig behavior changes These ship via the `oxc_resolver` 11.21.3 bump (#9841) and affect `resolve.tsconfigPaths` (Vite 8 resolves through oxc-resolver): - **Honor explicit non-TS extensions in `include`** (oxc-project/oxc-resolver#1213). `compilerOptions.paths` now resolve for importers whose extension is explicitly listed in a tsconfig's `include` (e.g. `src/**/*.vue`, `src/**/*.svelte`). Previously oxc-resolver filtered importers by extension before evaluating the `include` globs, so a `.vue`/`.svelte` file listed in `include` never matched its project and its `paths` were skipped. This unblocks the default create-vite Vue + TS layout (a solution-style root plus a referenced `tsconfig.app.json` that declares `paths` and `include: ["src/**/*.ts", "src/**/*.vue"]`). Matches vue-tsc and svelte-check, which register these extensions via TypeScript's `extraFileExtensions`. - **No fallback to the outermost tsconfig in auto-discovery** (oxc-project/oxc-resolver#1220). Auto-discovery no longer attaches the topmost ancestor `tsconfig.json` to a file that no project actually owns (via `files` / `include` / project references). Previously such a file inherited the outermost ancestor's `paths` / `baseUrl`, leaking aliases into files that project does not own. oxc-resolver now returns no config in that case, matching tsserver / typescript-go, which route such files to an inferred project with no aliases. ### 🚀 Features - add option named for invalid return type errors for more places (#9846) by @shulaoda - add option names for invalid return type errors (#9821) by @sapphi-red - transform: infer decorator strictNullChecks from tsconfig (#9590) by @kylecannon - expose React Compiler options for rolldown and Vite users (#9801) by @Boshen - tracing: gate chrome-json trace layer behind `chrome-tracing` feature (#9773) by @hyf0 - dev: align test-dev-server with Vite dev server (#9668) by @h-a-n-a ### 🐛 Bug Fixes - plugin_timings: point doc link to existing checks reference page (#9837) by @hyf0 - generator: correct contradictory panic message in cjs cross-chunk symbol lookup (#9836) by @hyf0 - esm: preserve with clause on export * from external (#9796) by @hyf0 - Make external_import_binding_merger deterministic (#9755) by @naruaway - surface invalid `manualCodeSplitting` group `test` regex as an error (#9792) by @shulaoda - avoid panic on `output.file` without a file name (#9789) by @shulaoda - avoid O(N^2) rendering of high-volume diagnostics (#9748) (#9749) by @IWANABETHATGUY - avoid panic on JSON numbers outside f64 range (#9788) by @shulaoda - deps: bump mimalloc-safe to 0.1.63 to fix worker_threads segfault (#9785) by @shulaoda - cache ESM evaluation errors (#9784) by @sapphi-red - wrap node require helper in pure IIFE (#9783) by @kb019 - lazy-barrel: load locally-used imports on a re-exported record (#9757) by @shulaoda - avoid dangling wrapped-ESM init call across chunks (#9502) (#9717) by @IWANABETHATGUY - dev: detect same-second rewrites in CI poll watcher (#9736) by @h-a-n-a - dev: force rebuild after HMR errors (#9686) by @h-a-n-a - dev: print build errors on browser refresh after a failed build (#9652) by @h-a-n-a ### 🚜 Refactor - single-source the chunk $N symbol-naming algorithm (#9831) by @Dunqing - simplify common_dir helper (#9857) by @IWANABETHATGUY - drop commondir crate in favor of in-house helper (#9849) by @Boshen - binding: extract helpers from normalize_binding_options (#9842) by @Boshen - move rolldown_filter_analyzer to tasks and scope oxc cfg feature (#9839) by @Boshen - options: merge manualCodeSplitting into codeSplitting object form (#9805) by @IWANABETHATGUY - options: support codeSplitting object form in CodeSplittingMode (#9804) by @IWANABETHATGUY - diagnostic: reuse ByteLocator for per-source line lookup (#9762) by @IWANABETHATGUY - remove redundant Arc around tracing spans (#9778) by @camc314 - remove unnecessary `Arc` around sourcemap sender (#9777) by @camc314 - rolldown_plugin_vite_wasm_fallback: remove the plugin (#9775) by @sapphi-red - binding: remove infer-able `napi(ts_type)` (#9737) by @sapphi-red - remove preprocessor span dedup (#9734) by @hyf0 - identify AST nodes by NodeId instead of Span/Address (#9609) by @IWANABETHATGUY ### 📚 Documentation - tsconfig: align auto-discovery docs with oxc-resolver behavior (#9845) by @shulaoda - relocate meta/design to internal-docs, split design from implementation (#9826) by @h-a-n-a - meta: add options normalization design doc (#9818) by @IWANABETHATGUY - document why the napi tracing feature is enabled (#9766) by @Boshen - dev: move test-dev-server test guidance into the testing docs (#9809) by @h-a-n-a ### ⚡ Performance - drop unused regex unicode property tables from the binding (#9848) by @Boshen - drop urlencoding crate in favor of percent-encoding (#9851) by @Boshen - drop owo-colors supports-colors feature in vite reporter (#9824) by @Boshen - skip enum member value extraction for non-TypeScript modules (#9840) by @shulaoda - rolldown: use unstable sort for itertools sorted_by at unique-key sites (#9827) by @Boshen - cheaper deterministic ordering in external import binding merger (#9810) by @IWANABETHATGUY - disable idna's ICU backend by pinning idna_adapter to 1.0.0 (-129 KB) (#9811) by @Boshen - size: use unstable sort where stability is unneeded (#9803) by @Boshen - remove num-format dependency from vite reporter (#9795) by @Boshen - reduce js callback error size (#9776) by @Boshen - rolldown_error: remove Debug supertrait from BuildEvent (#9798) by @Boshen - reduce plugin hook order code size (#9761) by @Boshen - deps: disable `infer` default features to reduce binary size (#9765) by @Boshen - reduce pluginable monomorphization size (#9771) by @Boshen - avoid rebuilding replace plugin values (#9764) by @Boshen - defer link-stage-output drop to rayon workers after output is produced (#9733) by @Brooooooklyn - tree-shaking: hoist already-included guard to call sites in inclusion DFS (#9738) by @Brooooooklyn - renamer: dedup before allocating the owned name in add_symbol_in_root_scope (#9740) by @Brooooooklyn ### 🧪 Testing - allocs: track allocation counts for rolldown_sourcemap (#9835) by @hyf0 - bench: add CodSpeed micro-benchmarks for rolldown_sourcemap (#9834) by @hyf0 - add cjs named export mutation test (#9823) by @sapphi-red - dev: restore shared-page reliability conventions in AGENTS.md (#9786) by @h-a-n-a - dev: add `AGENTS.md` test guidance for agents (#9763) by @h-a-n-a - dev: split out initial-build-error into its own playground (#9772) by @h-a-n-a - dev: align e2e suite with Vite and parallelize playgrounds (#9759) by @h-a-n-a - remove unnecessary module namespace object JSON serializations in tests (#9725) by @sapphi-red - use `assert.deepStrictEqual` instead of `assert.deepEqual` by using `assert/strict` instead of `assert` (#9724) by @sapphi-red - hmr: add test case for #5301 (#5302) by @sapphi-red - dev: add tests for dev-engine principles (#9720) by @h-a-n-a - dev: align dev-engine test harness with Vite (#9684) by @h-a-n-a ### ⚙️ Miscellaneous Tasks - deps: update napi to 3.9.3 (#9862) by @shulaoda - deps: update oxc to 0.137.0 (#9856) by @Boshen - re-enable default lld linker on x86_64-unknown-linux-gnu (#9855) by @Boshen - deps: bump vite-plus to 0.2.1 (#9850) by @Boshen - skills: translate _config.json when encoding rolldown REPL links (#9847) by @IWANABETHATGUY - deps: update oxc_resolver and oxc_resolver_napi to 11.21.3 (#9841) by @Boshen - pin vite-plus (vp) CLI to 0.1.24 in setup-vp (#9830) by @Boshen - add crate/package-level CODEOWNERS (#9819) by @IWANABETHATGUY - drop unused derive_more display feature from rolldown_plugin (#9820) by @Boshen - remove auto-assign PR workflow (#9807) by @IWANABETHATGUY - deps: update rollup submodule for tests to v4.62.0 (#9780) by @rolldown-guard[bot] - deps: update esbuild for tests to 0.28.1 (#9779) by @rolldown-guard[bot] - deps: update test262 submodule for tests (#9781) by @rolldown-guard[bot] - deps: update oxc to 0.136.0 (#9770) by @Boshen - add pull request template (#9756) by @sapphi-red - clarify `rolldown_plugin_vite_*` is compatible for the same minor (#9774) by @sapphi-red - deps: update github actions (#9745) by @renovate[bot] - deps: update rust crates (#9747) by @renovate[bot] - deps: update napi to v3.9.2 (#9744) by @renovate[bot] - deps: update npm packages (#9746) by @renovate[bot] - deps: update @napi-rs/cli and emnapi deps (#9741) by @Brooooooklyn - generator: fix `vp fmt` on Windows (#9727) by @sapphi-red - ban importing from `assert` and recommend `assert/strict` (#9726) by @sapphi-red ### ❤️ New Contributors * @naruaway made their first contribution in [#9755](#9755) * @kb019 made their first contribution in [#9783](#9783) Co-authored-by: shulaoda <165626830+shulaoda@users.noreply.github.com>
leegeunhyeok
added a commit
to rollipop-dev/rolldown
that referenced
this pull request
Jun 18, 2026
## [1.0.16] - 2026-06-18 ### 🚀 Features - add option named for invalid return type errors for more places (rolldown#9846) by `@shulaoda` - add option names for invalid return type errors (rolldown#9821) by `@sapphi-red` - transform: infer decorator strictNullChecks from tsconfig (rolldown#9590) by `@kylecannon` - expose React Compiler options for rolldown and Vite users (rolldown#9801) by `@Boshen` - tracing: gate chrome-json trace layer behind `chrome-tracing` feature (rolldown#9773) by `@hyf0` - dev: align test-dev-server with Vite dev server (rolldown#9668) by `@h-a-n-a` ### 🐛 Bug Fixes - plugin_timings: point doc link to existing checks reference page (rolldown#9837) by `@hyf0` - generator: correct contradictory panic message in cjs cross-chunk symbol lookup (rolldown#9836) by `@hyf0` - esm: preserve with clause on export * from external (rolldown#9796) by `@hyf0` - Make external_import_binding_merger deterministic (rolldown#9755) by `@naruaway` - surface invalid `manualCodeSplitting` group `test` regex as an error (rolldown#9792) by `@shulaoda` - avoid panic on `output.file` without a file name (rolldown#9789) by `@shulaoda` - avoid O(N^2) rendering of high-volume diagnostics (rolldown#9748) (rolldown#9749) by `@IWANABETHATGUY` - avoid panic on JSON numbers outside f64 range (rolldown#9788) by `@shulaoda` - deps: bump mimalloc-safe to 0.1.63 to fix worker_threads segfault (rolldown#9785) by `@shulaoda` - cache ESM evaluation errors (rolldown#9784) by `@sapphi-red` - wrap node require helper in pure IIFE (rolldown#9783) by `@kb019` - lazy-barrel: load locally-used imports on a re-exported record (rolldown#9757) by `@shulaoda` - avoid dangling wrapped-ESM init call across chunks (rolldown#9502) (rolldown#9717) by `@IWANABETHATGUY` - dev: detect same-second rewrites in CI poll watcher (rolldown#9736) by `@h-a-n-a` - dev: force rebuild after HMR errors (rolldown#9686) by `@h-a-n-a` - dev: print build errors on browser refresh after a failed build (rolldown#9652) by `@h-a-n-a` ### 🚜 Refactor - single-source the chunk $N symbol-naming algorithm (rolldown#9831) by `@Dunqing` - simplify common_dir helper (rolldown#9857) by `@IWANABETHATGUY` - drop commondir crate in favor of in-house helper (rolldown#9849) by `@Boshen` - binding: extract helpers from normalize_binding_options (rolldown#9842) by `@Boshen` - move rolldown_filter_analyzer to tasks and scope oxc cfg feature (rolldown#9839) by `@Boshen` - options: merge manualCodeSplitting into codeSplitting object form (rolldown#9805) by `@IWANABETHATGUY` - options: support codeSplitting object form in CodeSplittingMode (rolldown#9804) by `@IWANABETHATGUY` - diagnostic: reuse ByteLocator for per-source line lookup (rolldown#9762) by `@IWANABETHATGUY` - remove redundant Arc around tracing spans (rolldown#9778) by `@camc314` - remove unnecessary `Arc` around sourcemap sender (rolldown#9777) by `@camc314` - rolldown_plugin_vite_wasm_fallback: remove the plugin (rolldown#9775) by `@sapphi-red` - binding: remove infer-able `napi(ts_type)` (rolldown#9737) by `@sapphi-red` - remove preprocessor span dedup (rolldown#9734) by `@hyf0` - identify AST nodes by NodeId instead of Span/Address (rolldown#9609) by `@IWANABETHATGUY` ### 📚 Documentation - tsconfig: align auto-discovery docs with oxc-resolver behavior (rolldown#9845) by `@shulaoda` - relocate meta/design to internal-docs, split design from implementation (rolldown#9826) by `@h-a-n-a` - meta: add options normalization design doc (rolldown#9818) by `@IWANABETHATGUY` - document why the napi tracing feature is enabled (rolldown#9766) by `@Boshen` - dev: move test-dev-server test guidance into the testing docs (rolldown#9809) by `@h-a-n-a` ### ⚡ Performance - drop unused regex unicode property tables from the binding (rolldown#9848) by `@Boshen` - drop urlencoding crate in favor of percent-encoding (rolldown#9851) by `@Boshen` - drop owo-colors supports-colors feature in vite reporter (rolldown#9824) by `@Boshen` - skip enum member value extraction for non-TypeScript modules (rolldown#9840) by `@shulaoda` - rolldown: use unstable sort for itertools sorted_by at unique-key sites (rolldown#9827) by `@Boshen` - cheaper deterministic ordering in external import binding merger (rolldown#9810) by `@IWANABETHATGUY` - disable idna's ICU backend by pinning idna_adapter to 1.0.0 (-129 KB) (rolldown#9811) by `@Boshen` - size: use unstable sort where stability is unneeded (rolldown#9803) by `@Boshen` - remove num-format dependency from vite reporter (rolldown#9795) by `@Boshen` - reduce js callback error size (rolldown#9776) by `@Boshen` - rolldown_error: remove Debug supertrait from BuildEvent (rolldown#9798) by `@Boshen` - reduce plugin hook order code size (rolldown#9761) by `@Boshen` - deps: disable `infer` default features to reduce binary size (rolldown#9765) by `@Boshen` - reduce pluginable monomorphization size (rolldown#9771) by `@Boshen` - avoid rebuilding replace plugin values (rolldown#9764) by `@Boshen` - defer link-stage-output drop to rayon workers after output is produced (rolldown#9733) by `@Brooooooklyn` - tree-shaking: hoist already-included guard to call sites in inclusion DFS (rolldown#9738) by `@Brooooooklyn` - renamer: dedup before allocating the owned name in add_symbol_in_root_scope (rolldown#9740) by `@Brooooooklyn` ### 🧪 Testing - allocs: track allocation counts for rolldown_sourcemap (rolldown#9835) by `@hyf0` - bench: add CodSpeed micro-benchmarks for rolldown_sourcemap (rolldown#9834) by `@hyf0` - add cjs named export mutation test (rolldown#9823) by `@sapphi-red` - dev: restore shared-page reliability conventions in AGENTS.md (rolldown#9786) by `@h-a-n-a` - dev: add `AGENTS.md` test guidance for agents (rolldown#9763) by `@h-a-n-a` - dev: split out initial-build-error into its own playground (rolldown#9772) by `@h-a-n-a` - dev: align e2e suite with Vite and parallelize playgrounds (rolldown#9759) by `@h-a-n-a` - remove unnecessary module namespace object JSON serializations in tests (rolldown#9725) by `@sapphi-red` - use `assert.deepStrictEqual` instead of `assert.deepEqual` by using `assert/strict` instead of `assert` (rolldown#9724) by `@sapphi-red` - hmr: add test case for rolldown#5301 (rolldown#5302) by `@sapphi-red` - dev: add tests for dev-engine principles (rolldown#9720) by `@h-a-n-a` - dev: align dev-engine test harness with Vite (rolldown#9684) by `@h-a-n-a` ### ⚙️ Miscellaneous Tasks - add rollipop-integration skill by `@leegeunhyeok` - update esbuild snap diff metrics by `@leegeunhyeok` - sync upstream rolldown v1.1.2 by `@leegeunhyeok` - deps: update napi to 3.9.3 (rolldown#9862) by `@shulaoda` - deps: update oxc to 0.137.0 (rolldown#9856) by `@Boshen` - re-enable default lld linker on x86_64-unknown-linux-gnu (rolldown#9855) by `@Boshen` - deps: bump vite-plus to 0.2.1 (rolldown#9850) by `@Boshen` - skills: translate _config.json when encoding rolldown REPL links (rolldown#9847) by `@IWANABETHATGUY` - deps: update oxc_resolver and oxc_resolver_napi to 11.21.3 (rolldown#9841) by `@Boshen` - pin vite-plus (vp) CLI to 0.1.24 in setup-vp (rolldown#9830) by `@Boshen` - add crate/package-level CODEOWNERS (rolldown#9819) by `@IWANABETHATGUY` - drop unused derive_more display feature from rolldown_plugin (rolldown#9820) by `@Boshen` - remove auto-assign PR workflow (rolldown#9807) by `@IWANABETHATGUY` - deps: update rollup submodule for tests to v4.62.0 (rolldown#9780) by `@rolldown-guard[bot]` - deps: update esbuild for tests to 0.28.1 (rolldown#9779) by `@rolldown-guard[bot]` - deps: update test262 submodule for tests (rolldown#9781) by `@rolldown-guard[bot]` - deps: update oxc to 0.136.0 (rolldown#9770) by `@Boshen` - add pull request template (rolldown#9756) by `@sapphi-red` - clarify `rolldown_plugin_vite_*` is compatible for the same minor (rolldown#9774) by `@sapphi-red` - deps: update github actions (rolldown#9745) by `@renovate[bot]` - deps: update rust crates (rolldown#9747) by `@renovate[bot]` - deps: update napi to v3.9.2 (rolldown#9744) by `@renovate[bot]` - deps: update npm packages (rolldown#9746) by `@renovate[bot]` - deps: update @napi-rs/cli and emnapi deps (rolldown#9741) by `@Brooooooklyn` - generator: fix `vp fmt` on Windows (rolldown#9727) by `@sapphi-red` - ban importing from `assert` and recommend `assert/strict` (rolldown#9726) by `@sapphi-red` Co-authored-by: leegeunhyeok <26512984+leegeunhyeok@users.noreply.github.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
In the
Renamer::add_symbol_in_root_scopedeconflict path, an ownedoriginal_name(CompactStr) was built before thecanonical_names.contains_key(&canonical_ref)dedup check. On apps/10000, ~19,870 of ~59,943 calls are re-adds of an already-presentcanonical_ref(31.7%) — every one of those built and then discarded the owned name.This hoists the dedup check above the name construction so an already-present
canonical_refreturns before theCompactStrallocation. It's guarded byneeds_deconflictto preserve the original control flow exactly: the old unguarded check was only reachable on theneeds_deconflictpath (the!needs_deconflictbranch returns earlier, and still needs the built name to insert).Correctness
Behavior-preserving and byte-identical (
main.js+main.js.mapsha256 match baseline on apps/10000). Verified by cases:!needs_deconflict→ unchanged: builds the name and inserts (the new guard is skipped).needs_deconflict+ already present → returns without state change (only difference vs before: the wasted name-build is skipped).needs_deconflict+ not present → falls through to the same fast/slow path.Performance
Removes ~19,870 wasted
CompactStrbuilds per build. (Note: the deconflict path's remaining cost is genuine — ~66.7% of symbols on this workload really do collide and need renaming; this PR only removes the pre-dedup waste, nothing structural.) Local wall is within ambient noise; relying on CodSpeed for the clean number.+8 / -4, one file. fmt/clippy clean.🤖 Generated with Claude Code
Note
Low Risk
Behavior-preserving reorder of an existing early return; only affects performance on the chunk symbol deconflict hot path, not naming semantics.
Overview
Renamer::add_symbol_in_root_scopenow returns early on duplicatecanonical_refentries before constructing the ownedoriginal_name(CompactStr), but only whenneeds_deconflictis true.The
!needs_deconflictpath is unchanged: it still builds the name and inserts. On large bundles, many deconflict calls are no-op re-adds; skipping the JSX-capitalization andCompactStrwork on those calls removes redundant allocations without changing rename results.Reviewed by Cursor Bugbot for commit 08280d5. Bugbot is set up for automated code reviews on this repo. Configure here.