perf: improve get mode

[LingyuCoder]

Summary

If a module has been processed by some dependencies before, then the same module introduced by left dependencies will not affect the result of get mode

Related links

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

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[github-actions]

📝 Benchmark detail: Open

Name	Base (2025-09-17 03ab52a)	Current	Change
10000_big_production-mode_disable-minimize + exec	28 s ± 1.21 s	28 s ± 877 ms	-0.13 %
10000_development-mode + exec	1.63 s ± 18 ms	1.64 s ± 165 ms	+0.81 %
10000_development-mode_hmr + exec	704 ms ± 14 ms	691 ms ± 11 ms	-1.87 %
10000_development-mode_noop-loader + exec	2.56 s ± 38 ms	2.61 s ± 176 ms	+2.06 %
10000_production-mode + exec	1.65 s ± 22 ms	1.69 s ± 152 ms	+2.35 %
10000_production-mode_persistent-cold + exec	1.84 s ± 58 ms	1.81 s ± 26 ms	-1.51 %
10000_production-mode_persistent-hot + exec	1.35 s ± 46 ms	1.34 s ± 21 ms	-0.40 %
arco-pro_development-mode + exec	1.73 s ± 107 ms	1.74 s ± 91 ms	+0.61 %
arco-pro_development-mode_hmr + exec	368 ms ± 0.6 ms	368 ms ± 1.2 ms	-0.03 %
arco-pro_production-mode + exec	3.17 s ± 122 ms	3.18 s ± 96 ms	+0.40 %
arco-pro_production-mode_generate-package-json-webpack-plugin + exec	3.33 s ± 86 ms	3.29 s ± 104 ms	-1.13 %
arco-pro_production-mode_persistent-cold + exec	3.37 s ± 92 ms	3.31 s ± 289 ms	-1.89 %
arco-pro_production-mode_persistent-hot + exec	1.94 s ± 115 ms	1.95 s ± 54 ms	+0.55 %
arco-pro_production-mode_traverse-chunk-modules + exec	3.22 s ± 83 ms	3.21 s ± 146 ms	-0.34 %
large-dyn-imports_development-mode + exec	1.84 s ± 38 ms	1.83 s ± 34 ms	-0.61 %
large-dyn-imports_production-mode + exec	1.84 s ± 40 ms	1.82 s ± 47 ms	-0.82 %
threejs_development-mode_10x + exec	1.48 s ± 23 ms	1.47 s ± 18 ms	-0.70 %
threejs_development-mode_10x_hmr + exec	932 ms ± 24 ms	937 ms ± 34 ms	+0.57 %
threejs_production-mode_10x + exec	4.45 s ± 215 ms	4.45 s ± 46 ms	-0.09 %
threejs_production-mode_10x_persistent-cold + exec	4.55 s ± 38 ms	4.6 s ± 66 ms	+1.25 %
threejs_production-mode_10x_persistent-hot + exec	4.06 s ± 44 ms	4.13 s ± 307 ms	+1.76 %
10000_big_production-mode_disable-minimize + rss memory	8842 MiB ± 173 MiB	8711 MiB ± 341 MiB	-1.48 %
10000_development-mode + rss memory	673 MiB ± 5.33 MiB	693 MiB ± 15.8 MiB	+3.09 %
10000_development-mode_hmr + rss memory	819 MiB ± 32.3 MiB	818 MiB ± 22.4 MiB	-0.05 %
10000_development-mode_noop-loader + rss memory	968 MiB ± 18.5 MiB	975 MiB ± 28.5 MiB	+0.70 %
10000_production-mode + rss memory	629 MiB ± 10 MiB	669 MiB ± 19.4 MiB	+6.29 %
10000_production-mode_persistent-cold + rss memory	759 MiB ± 37.4 MiB	771 MiB ± 36.3 MiB	+1.61 %
10000_production-mode_persistent-hot + rss memory	759 MiB ± 48.5 MiB	759 MiB ± 34 MiB	+0.02 %
arco-pro_development-mode + rss memory	557 MiB ± 59.8 MiB	598 MiB ± 53.2 MiB	+7.22 %
arco-pro_development-mode_hmr + rss memory	464 MiB ± 3.41 MiB	474 MiB ± 22.4 MiB	+2.15 %
arco-pro_production-mode + rss memory	698 MiB ± 90.4 MiB	702 MiB ± 75.1 MiB	+0.66 %
arco-pro_production-mode_generate-package-json-webpack-plugin + rss memory	700 MiB ± 106 MiB	708 MiB ± 70.9 MiB	+1.27 %
arco-pro_production-mode_persistent-cold + rss memory	766 MiB ± 100 MiB	766 MiB ± 81.3 MiB	-0.07 %
arco-pro_production-mode_persistent-hot + rss memory	600 MiB ± 92.4 MiB	620 MiB ± 69.5 MiB	+3.35 %
arco-pro_production-mode_traverse-chunk-modules + rss memory	689 MiB ± 54.6 MiB	706 MiB ± 62.7 MiB	+2.45 %
large-dyn-imports_development-mode + rss memory	694 MiB ± 3.99 MiB	695 MiB ± 7.12 MiB	+0.23 %
large-dyn-imports_production-mode + rss memory	591 MiB ± 4.64 MiB	601 MiB ± 9.51 MiB	+1.53 %
threejs_development-mode_10x + rss memory	598 MiB ± 14 MiB	594 MiB ± 17.4 MiB	-0.65 %
threejs_development-mode_10x_hmr + rss memory	846 MiB ± 49.6 MiB	845 MiB ± 74.4 MiB	-0.12 %
threejs_production-mode_10x + rss memory	777 MiB ± 166 MiB	770 MiB ± 198 MiB	-0.86 %
threejs_production-mode_10x_persistent-cold + rss memory	824 MiB ± 22.1 MiB	819 MiB ± 29.2 MiB	-0.52 %
threejs_production-mode_10x_persistent-hot + rss memory	721 MiB ± 51.8 MiB	714 MiB ± 41.8 MiB	-0.89 %

[github-actions]

📦 Binary Size-limit

Comparing 0cc8976 to chore: release v1.5.5 (#11688) by Gengkun

❌ Size increased by 128bytes from 47.44MB to 47.44MB (⬆️0.00%)

[codspeed-hq]

CodSpeed Performance Report

Merging #11695 will not alter performance

_{Comparing perf/get-mode (0cc8976) with main (5ccedf1)}

Summary

✅ 17 untouched

[Copilot]

Pull Request Overview

This PR optimizes the determine_export_assignments function by avoiding redundant processing of modules that have already been handled. It introduces a tracking mechanism to skip duplicate module processing, which should improve performance when the same module is introduced by multiple dependencies.

• Adds deduplication logic to prevent reprocessing the same module
• Introduces a handled_modules set to track processed modules
• Skips export processing for already-handled modules while maintaining index consistency

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