Avatar for the swc-project user
swc-project
swc
BlogDocsChangelog

perf: speed up swc_ecma_codegen JsWriter hot path

#11870
Comparing
hardfist:codex/ecma-codegen-10pct-speedup
(
9ac84bc
) with
main
(
aa5b539
)
CodSpeed Performance Gauge
+10%
Improvement
19
Untouched
200
Ignored
1
Skipped
31

Benchmarks

251 total
es/large/codegen/es2017
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
34 ms28.8 ms
es/large/codegen/es2019
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
33.9 ms28.9 ms
es/large/codegen/es2018
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
34 ms28.9 ms
es/large/codegen/es3
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
33.9 ms28.8 ms
es/large/codegen/es2020
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
34 ms28.9 ms
es/large/codegen/es5
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
33.9 ms28.9 ms
es/large/codegen/es2016
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
33.9 ms28.9 ms
es/large/codegen/es2015
crates/swc/benches/typescript.rs::benches::codegen_group
CodSpeed Performance Gauge
+18%
33.9 ms28.9 ms
es/codegen/large
crates/swc_ecma_codegen/benches/bench.rs::benches::bench_cases
CodSpeed Performance Gauge
+15%
641.5 µs556.1 µs
es/codegen/with-parser/large
crates/swc_ecma_codegen/benches/with_parse.rs::benches::bench_cases
CodSpeed Performance Gauge
+9%
1,062.7 µs976.7 µs
es/codegen/colors
crates/swc_ecma_codegen/benches/bench.rs::benches::bench_cases
CodSpeed Performance Gauge
+6%
71.9 µs68 µs
es/codegen/with-parser/colors
crates/swc_ecma_codegen/benches/with_parse.rs::benches::bench_cases
CodSpeed Performance Gauge
+3%
149.9 µs145.4 µs
es/oxc/benches/assets/table.tsx/sourceMap=true/reactDev=true
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+3%
8.1 ms7.9 ms
es/oxc/benches/assets/parser.ts/sourceMap=true/reactDev=true
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+2%
83.5 ms81.5 ms
es/oxc/benches/assets/table.tsx/sourceMap=true/reactDev=false
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+2%
7.3 ms7.2 ms
es/oxc/benches/assets/parser.ts/sourceMap=true/reactDev=false
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+2%
83.5 ms81.5 ms
es/oxc/benches/assets/renderer.ts/sourceMap=true/reactDev=true
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+2%
13.6 ms13.3 ms
es/oxc/benches/assets/renderer.ts/sourceMap=true/reactDev=false
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+2%
13.6 ms13.3 ms
es/oxc/benches/assets/UserSettings.tsx/sourceMap=true/reactDev=false
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+2%
1.2 ms1.2 ms
es/oxc/benches/assets/UserSettings.tsx/sourceMap=true/reactDev=true
crates/swc/benches/oxc.rs::benches::full_group
CodSpeed Performance Gauge
+2%
1.3 ms1.3 ms
es/large/minify/libraries/terser
crates/swc/benches/minify.rs::benches::files_group::es/large/minify/libraries
CodSpeed Performance Gauge
+2%
460.5 ms452.3 ms
es/lints/libs/three
crates/swc_ecma_lints/benches/all.rs::files::bench_files::es/lints/libs
CodSpeed Performance Gauge
+2%
50.9 ms50 ms
es/large/minify/libraries/three
crates/swc/benches/minify.rs::benches::files_group::es/large/minify/libraries
CodSpeed Performance Gauge
+2%
820.9 ms808.2 ms
es/large/minify/libraries/typescript
crates/swc/benches/minify.rs::benches::files_group::es/large/minify/libraries
CodSpeed Performance Gauge
+2%
4.6 s4.5 s
es/large/minify/libraries/echarts
crates/swc/benches/minify.rs::benches::files_group::es/large/minify/libraries
CodSpeed Performance Gauge
+1%
2 s1.9 s

Commits

Click on a commit to change the comparison range
Base
main
aa5b539
+10.18%
perf(ecma_codegen): streamline write hot path branching
5145cc0
2 months ago
by hardfist
-10.18%
Merge remote-tracking branch 'origin/main' into codex/ecma-codegen-10pct-speedup
b425240
2 months ago
by hardfist
+9.83%
fix(ecma_codegen): remove stale srcmap hash dedupe path
9ac84bc
2 months ago
by hardfist
© 2026 CodSpeed Technology
Home Terms Privacy Docs