perf: reduce intermediate allocations in `collapse_sourcemaps` by Boshen · Pull Request #8821 · rolldown/rolldown

Boshen · 2026-03-20T14:56:35Z

Summary

Pre-reverse lookup table pairs during construction to avoid creating a Rev iterator adapter on every token lookup
Collect tokens directly to Box<[Token]> instead of Vec<Token> + .into_boxed_slice()
Use .cloned() instead of .map(Arc::clone) for names and sources

🤖 Generated with Claude Code

netlify · 2026-03-20T14:56:54Z

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github-actions · 2026-03-20T15:13:03Z

Benchmarks Rust

target: main(4705026)
pr: perf/collapse-sourcemaps-allocations(806ebaa)

group                                                        pr                                     target
-----                                                        --                                     ------
bundle/bundle@multi-duplicated-top-level-symbol              1.14     75.8±3.07ms        ? ?/sec    1.00     66.3±3.06ms        ? ?/sec
bundle/bundle@multi-duplicated-top-level-symbol-sourcemap    1.12     83.0±3.02ms        ? ?/sec    1.00     74.1±2.90ms        ? ?/sec
bundle/bundle@rome_ts                                        1.15    163.5±4.00ms        ? ?/sec    1.00    142.1±6.03ms        ? ?/sec
bundle/bundle@rome_ts-sourcemap                              1.12    184.2±4.80ms        ? ?/sec    1.00    164.8±6.74ms        ? ?/sec
bundle/bundle@threejs                                        1.16     73.3±3.60ms        ? ?/sec    1.00     63.0±3.80ms        ? ?/sec
bundle/bundle@threejs-sourcemap                              1.15     82.7±4.23ms        ? ?/sec    1.00     71.7±2.79ms        ? ?/sec
bundle/bundle@threejs10x                                     1.03   750.1±14.17ms        ? ?/sec    1.00   725.9±13.19ms        ? ?/sec
bundle/bundle@threejs10x-sourcemap                           1.03   848.3±14.92ms        ? ?/sec    1.00   825.8±10.20ms        ? ?/sec

codspeed-hq · 2026-03-20T15:20:49Z

Merging this PR will not alter performance

✅ 6 untouched benchmarks
⏩ 8 skipped benchmarks¹

_{Comparing perf/collapse-sourcemaps-allocations (806ebaa) with main (6ee414a)²}

8 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. ↩
No successful run was found on main (4705026) during the generation of this report, so 6ee414a was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

Boshen · 2026-03-20T16:13:27Z

Merge activity

Mar 20, 4:13 PM UTC: The merge label 'graphite: merge-when-ready' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
Mar 20, 4:13 PM UTC: Boshen added this pull request to the Graphite merge queue.
Mar 20, 4:18 PM UTC: Merged by the Graphite merge queue.

## Summary - Pre-reverse lookup table pairs during construction to avoid creating a `Rev` iterator adapter on every token lookup - Collect tokens directly to `Box<[Token]>` instead of `Vec<Token>` + `.into_boxed_slice()` - Use `.cloned()` instead of `.map(Arc::clone)` for names and sources Closes #8632 🤖 Generated with [Claude Code](https://claude.com/claude-code)

@IWANABETHATGUY

## [1.0.0-rc.11] - 2026-03-23 ### 🚀 Features - magicString replace with regex (#8802) by @IWANABETHATGUY - support `output.sourcemapExcludeSources` option (#8828) by @sapphi-red - support `getIndentString` in MagicString (#8775) by @IWANABETHATGUY - MagicString ignoreList support (#8773) by @IWANABETHATGUY ### 🐛 Bug Fixes - types: remove `pluginName` from `MinimalPluginContext` (#8864) by @sapphi-red - do not report eval?.() as direct eval (#8860) by @IWANABETHATGUY - handle negative indices, overlapping ranges, and moved content in MagicString remove (#8829) by @IWANABETHATGUY - enable arbitrary_precision for serde_json to fix JSON float parsing (#8848) by @elderapo - resolve TypeScript lint errors (#8841) by @Boshen - avoid panic on multi-byte UTF-8 chars in hash placeholder iterator (#8790) by @shulaoda - ci: skip failing vite build watch raw query test (#8840) by @Boshen - ci: use step-level env override to unset VITE_PLUS_CLI_BIN in vite tests (#8838) by @Boshen - ci: move vite tests into CI workflow by @Boshen - ci: unset all VITE_PLUS_* env vars in vite-tests workflow (#8837) by @Boshen - test: skip watch CLI tests on Windows (#8830) by @Boshen - ci: unset VITE_PLUS_CLI_BIN in vite-tests workflow (#8832) by @Boshen - remove redundant bare side-effect imports in entry/facade chunks (#8804) by @h-a-n-a - magicString prepend issues (#8797) by @IWANABETHATGUY - ci: use `vpx` instead of `vp exec` for `pkg-pr-new` (#8827) by @Boshen - set `order` for callable plugins (#8815) by @sapphi-red - handle reversed slice ranges with moved content (#8750) by @IWANABETHATGUY - update emnapi to latest to avoid version mismatch (#8781) by @sapphi-red - external.md on Windows OS (#8780) by @bddjr - align MagicString length/isEmpty with reference magic-string (#8776) by @IWANABETHATGUY ### 🚜 Refactor - extract canonical_ref_resolving_namespace helper (#8836) by @Boshen ### 📚 Documentation - improve external examples for cross-platform correctness (#8786) by @hyf0-agent - update reference to transform function in plugin API documentation (#8778) by @zOadT ### ⚡ Performance - reduce timing of `dervie_entries_aware_chunk_name` (#8847) by @AliceLanniste - bench: remove redundant sourcemap benchmark cases (#8825) by @Boshen - reduce intermediate allocations in `collapse_sourcemaps` (#8821) by @Boshen - enable parallel AST cloning on macOS (#8814) by @Boshen ### 🧪 Testing - watch: use polling watcher and retry for watch error test (#8772) by @sapphi-red ### ⚙️ Miscellaneous Tasks - justfile: skip setup-vite-plus if vp is already installed (#8862) by @Boshen - add expectWarning option to test config (#8861) by @IWANABETHATGUY - justfile: support windows for `just setup` (#8846) by @AliceLanniste - deps: update rust crates (#8852) by @renovate[bot] - deps: update endbug/version-check action to v3 (#8855) by @renovate[bot] - deps: update github-actions (#8853) by @renovate[bot] - deps: update dependency vitepress to v2.0.0-alpha.17 (#8854) by @renovate[bot] - deps: update npm packages (#8851) by @renovate[bot] - bench: use mimalloc as global allocator in bench crate (#8844) by @IWANABETHATGUY - reuse native build artifact in node-validation job (#8826) by @Boshen - speed up CodSpeed benchmark build by disabling LTO (#8824) by @Boshen - remove redundant critcmp benchmark job (#8823) by @Boshen - deps: update rust crate oxc_sourcemap to v6.1.0 (#8785) by @renovate[bot] - node: migrate oxlint and oxfmt to Vite+ (#8813) by @Boshen - revert namespace runners for release build jobs (#8820) by @Boshen - migrate runners to namespace (#8819) by @Boshen - test: relax test utils path assertion to support git worktrees (#8816) by @younggglcy - rename `examples/lazy` to `examples/lazy-compilation` (#8789) by @shulaoda - improve "needs reproduction" wording by @Boshen - deps: update dependency oxlint-tsgolint to v0.17.1 (#8807) by @renovate[bot] - enable 7 previously-skipped MagicString tests (#8771) by @IWANABETHATGUY - upgrade oxc to 0.121.0 (#8784) by @shulaoda - increase Windows dev drive size from 12GB to 20GB (#8779) by @Copilot ### ❤️ New Contributors * @elderapo made their first contribution in [#8848](#8848) * @younggglcy made their first contribution in [#8816](#8816) * @bddjr made their first contribution in [#8780](#8780) * @zOadT made their first contribution in [#8778](#8778) Co-authored-by: shulaoda <165626830+shulaoda@users.noreply.github.com>

@IWANABETHATGUY

## [1.0.0-rc.11] - 2026-03-23 ### 🚀 Features - magicString replace with regex (#8802) by @IWANABETHATGUY - support `output.sourcemapExcludeSources` option (#8828) by @sapphi-red - support `getIndentString` in MagicString (#8775) by @IWANABETHATGUY - MagicString ignoreList support (#8773) by @IWANABETHATGUY ### 🐛 Bug Fixes - forward test filters through vp run (#8870) by @younggglcy - types: remove `pluginName` from `MinimalPluginContext` (#8864) by @sapphi-red - do not report eval?.() as direct eval (#8860) by @IWANABETHATGUY - handle negative indices, overlapping ranges, and moved content in MagicString remove (#8829) by @IWANABETHATGUY - enable arbitrary_precision for serde_json to fix JSON float parsing (#8848) by @elderapo - resolve TypeScript lint errors (#8841) by @Boshen - avoid panic on multi-byte UTF-8 chars in hash placeholder iterator (#8790) by @shulaoda - ci: skip failing vite build watch raw query test (#8840) by @Boshen - ci: use step-level env override to unset VITE_PLUS_CLI_BIN in vite tests (#8838) by @Boshen - ci: move vite tests into CI workflow by @Boshen - ci: unset all VITE_PLUS_* env vars in vite-tests workflow (#8837) by @Boshen - test: skip watch CLI tests on Windows (#8830) by @Boshen - ci: unset VITE_PLUS_CLI_BIN in vite-tests workflow (#8832) by @Boshen - remove redundant bare side-effect imports in entry/facade chunks (#8804) by @h-a-n-a - magicString prepend issues (#8797) by @IWANABETHATGUY - ci: use `vpx` instead of `vp exec` for `pkg-pr-new` (#8827) by @Boshen - set `order` for callable plugins (#8815) by @sapphi-red - handle reversed slice ranges with moved content (#8750) by @IWANABETHATGUY - update emnapi to latest to avoid version mismatch (#8781) by @sapphi-red - external.md on Windows OS (#8780) by @bddjr - align MagicString length/isEmpty with reference magic-string (#8776) by @IWANABETHATGUY ### 🚜 Refactor - extract canonical_ref_resolving_namespace helper (#8836) by @Boshen ### 📚 Documentation - improve external examples for cross-platform correctness (#8786) by @hyf0-agent - update reference to transform function in plugin API documentation (#8778) by @zOadT ### ⚡ Performance - reduce timing of `dervie_entries_aware_chunk_name` (#8847) by @AliceLanniste - bench: remove redundant sourcemap benchmark cases (#8825) by @Boshen - reduce intermediate allocations in `collapse_sourcemaps` (#8821) by @Boshen - enable parallel AST cloning on macOS (#8814) by @Boshen ### 🧪 Testing - watch: use polling watcher and retry for watch error test (#8772) by @sapphi-red ### ⚙️ Miscellaneous Tasks - deps: update dependency @oxc-project/types to v0.122.0 (#8873) by @renovate[bot] - publish-to-npm: use correct vp pm publish (#8871) by @shulaoda - justfile: skip setup-vite-plus if vp is already installed (#8862) by @Boshen - add expectWarning option to test config (#8861) by @IWANABETHATGUY - justfile: support windows for `just setup` (#8846) by @AliceLanniste - deps: update rust crates (#8852) by @renovate[bot] - deps: update endbug/version-check action to v3 (#8855) by @renovate[bot] - deps: update github-actions (#8853) by @renovate[bot] - deps: update dependency vitepress to v2.0.0-alpha.17 (#8854) by @renovate[bot] - deps: update npm packages (#8851) by @renovate[bot] - bench: use mimalloc as global allocator in bench crate (#8844) by @IWANABETHATGUY - reuse native build artifact in node-validation job (#8826) by @Boshen - speed up CodSpeed benchmark build by disabling LTO (#8824) by @Boshen - remove redundant critcmp benchmark job (#8823) by @Boshen - deps: update rust crate oxc_sourcemap to v6.1.0 (#8785) by @renovate[bot] - node: migrate oxlint and oxfmt to Vite+ (#8813) by @Boshen - revert namespace runners for release build jobs (#8820) by @Boshen - migrate runners to namespace (#8819) by @Boshen - test: relax test utils path assertion to support git worktrees (#8816) by @younggglcy - rename `examples/lazy` to `examples/lazy-compilation` (#8789) by @shulaoda - improve "needs reproduction" wording by @Boshen - deps: update dependency oxlint-tsgolint to v0.17.1 (#8807) by @renovate[bot] - enable 7 previously-skipped MagicString tests (#8771) by @IWANABETHATGUY - upgrade oxc to 0.121.0 (#8784) by @shulaoda - increase Windows dev drive size from 12GB to 20GB (#8779) by @Copilot ### ❤️ New Contributors * @younggglcy made their first contribution in [#8870](#8870) * @elderapo made their first contribution in [#8848](#8848) * @bddjr made their first contribution in [#8780](#8780) * @zOadT made their first contribution in [#8778](#8778) --------- Co-authored-by: shulaoda <165626830+shulaoda@users.noreply.github.com>

github-actions bot assigned Boshen Mar 20, 2026

Boshen force-pushed the perf/collapse-sourcemaps-allocations branch 2 times, most recently from 526e658 to ba4f08e Compare March 20, 2026 15:35

Boshen requested a review from IWANABETHATGUY March 20, 2026 16:01

Boshen assigned IWANABETHATGUY and unassigned Boshen Mar 20, 2026

IWANABETHATGUY approved these changes Mar 20, 2026

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Boshen added the graphite: merge-when-ready label Mar 20, 2026

graphite-app bot force-pushed the perf/collapse-sourcemaps-allocations branch from 806ebaa to 7e2b85b Compare March 20, 2026 16:14

graphite-app bot merged commit 7e2b85b into main Mar 20, 2026
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graphite-app bot removed the graphite: merge-when-ready label Mar 20, 2026

graphite-app bot deleted the perf/collapse-sourcemaps-allocations branch March 20, 2026 16:18

github-actions bot mentioned this pull request Mar 23, 2026

release: v1.0.0-rc.11 #8868

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release: v1.0.0-rc.11 #8872

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release: v1.0.0-rc.11 #8876

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perf: reduce intermediate allocations in `collapse_sourcemaps`#8821

perf: reduce intermediate allocations in `collapse_sourcemaps`#8821
graphite-app[bot] merged 1 commit intomainfrom
perf/collapse-sourcemaps-allocations

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Boshen commented Mar 20, 2026

Summary

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Benchmarks Rust

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Merging this PR will not alter performance

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