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perf: speed up swc_ecma_codegen JsWriter hot path#11870

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perf: speed up swc_ecma_codegen JsWriter hot path#11870
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hardfist:codex/ecma-codegen-10pct-speedup

fix(ecma_codegen): remove stale srcmap hash dedupe path

9ac84bc
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CodSpeed HQ / CodSpeed Performance Analysis succeeded May 20, 2026 in 0s

Performance Gate Passed

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 19 improved benchmarks
✅ 200 untouched benchmarks
⏩ 31 skipped benchmarks1

Performance Changes

Benchmark BASE HEAD Efficiency
⚡ es/oxc/benches/assets/table.tsx/sourceMap=true/reactDev=false 7.3 ms 7.2 ms +2.38%
⚡ es/oxc/benches/assets/table.tsx/sourceMap=true/reactDev=true 8.1 ms 7.9 ms +2.73%
⚡ es/large/codegen/es2015 33.9 ms 28.9 ms +17.53%
⚡ es/large/codegen/es2016 33.9 ms 28.9 ms +17.61%
⚡ es/large/codegen/es2017 34 ms 28.8 ms +18.07%
⚡ es/large/codegen/es2018 34 ms 28.9 ms +17.67%
⚡ es/large/codegen/es2019 33.9 ms 28.9 ms +17.67%
⚡ es/large/codegen/es2020 34 ms 28.9 ms +17.63%
⚡ es/large/codegen/es3 33.9 ms 28.8 ms +17.66%
⚡ es/large/codegen/es5 33.9 ms 28.9 ms +17.63%
⚡ es/oxc/benches/assets/parser.ts/sourceMap=true/reactDev=false 83.5 ms 81.5 ms +2.37%
⚡ es/oxc/benches/assets/parser.ts/sourceMap=true/reactDev=true 83.5 ms 81.5 ms +2.43%
⚡ es/oxc/benches/assets/renderer.ts/sourceMap=true/reactDev=false 13.6 ms 13.3 ms +2.31%
⚡ es/oxc/benches/assets/renderer.ts/sourceMap=true/reactDev=true 13.6 ms 13.3 ms +2.37%
⚡ es/oxc/benches/assets/UserSettings.tsx/sourceMap=true/reactDev=false 1.2 ms 1.2 ms +2.14%
⚡ es/codegen/with-parser/colors 149.9 µs 145.4 µs +3.13%
⚡ es/codegen/colors 71.9 µs 68 µs +5.72%
⚡ es/codegen/large 641.5 µs 556.1 µs +15.35%
⚡ es/codegen/with-parser/large 1,062.7 µs 976.7 µs +8.8%

Tip

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Comparing hardfist:codex/ecma-codegen-10pct-speedup (9ac84bc) with main (aa5b539)

Open in CodSpeed

Footnotes

  1. 31 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. ↩

View more details on CodSpeed HQ