perf(core): optimize module rendering for chunk assets

[LingyuCoder]

Summary

• reuse the rendered module runtime scope across modules in the same chunk
• build module factory arguments directly instead of allocating and joining temporary strings
• avoid cloning chunk init fragments and preallocate module result containers
• reuse module identifiers across rendering lookups

Performance

Measured with the React 10k production fixture in Docker using targeted Valgrind Callgrind instrumentation:

• targeted instruction count: 43,894,917 -> 19,396,556 (-55.81%)
• create chunk assets stage median: 10.068 ms -> 9.463 ms (-6.00%)
• all 19 emitted files remained byte-for-byte identical to the baseline

Related links

N/A

Checklist

• Tests updated (not required for behavior-preserving refactoring).
• Documentation updated (not required).

Validation

• cargo fmt --all --check
• cargo check -p rspack_plugin_javascript -p rspack_plugin_esm_library
• pnpm run build:binding:dev
• pnpm run test:unit

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-08-29T18:07:03.688646Z	9435e69	PR opened

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[github-actions]

📦 Binary Size-limit

Comparing 9435e69 to chore(deps): update dependency @module-federation/runtime-tools to v2.9.0 (#15386) by renovate[bot]

🙈 Size remains the same at 68.30MB

[github-actions]

Rsdoctor Bundle Diff Analysis

Found 5 projects in monorepo, 0 projects with changes.

📊 Quick Summary

Project	Total Size	Gzip Size	Change	Gzip Change
popular-libs	1.7 MB	556.5 KB	0	0
react-1k	823.1 KB	218.4 KB	0	0
react-10k	5.6 MB	1.3 MB	0	0
react-5k	2.7 MB	669.3 KB	0	0
ui-components	4.9 MB	1.4 MB	0	0

Generated by Rsdoctor GitHub Action

[codspeed-hq]

Merging this PR will not alter performance

✅ 50 untouched benchmarks
⏩ 47 skipped benchmarks¹

---

_{Comparing seal/optimize-create-chunk-assets (9435e69) with main (a68bb1e)}

Footnotes

1. 47 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. ↩