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Latest Results

fix(ts/fast-strip): reject unsafe assertion erasure in binary expressions

magic-akari:fix/type-strip-assertions

10 hours ago

fix(ts/fast-strip): reject unsafe assertion erasure in binary expressions

magic-akari:fix/type-strip-assertions

12 hours ago

perf(es/codegen): remove JsWriter last_srcmap cache (#11869) **Description:** I removed the `last_srcmap` cache because its impact appears to be negligible. In local A/B walltime benchmarks for `es/codegen/large`, removing `last_srcmap` did not produce a stable regression beyond benchmark noise. Since `srcmap_done` still handles source map deduplication, this keeps the writer simpler while preserving behavior. Let's see what CI/CodSpeed reports for this change. **Related issue:** - #11867

main

17 hours ago

perf(ecma_codegen): streamline write hot path branching

hardfist:codex/ecma-codegen-10pct-speedup

20 hours ago

perf(es/codegen): remove JsWriter last_srcmap cache

magic-akari:chore/ecma-codegen

20 hours ago

chore(es/optimization): Fix typos in simplify expr comments

parkhojeong:chore/typo-fixes

21 hours ago

perf(es/codegen): speed up JsWriter position and srcmap tracking (#11867) **Description:** - Micro-optimize `swc_ecma_codegen::text_writer::JsWriter` in hot paths used during code emission. - Add fast paths in `update_pos` for common ASCII/no-newline tokens and single-byte writes. - Avoid immediate duplicate source-map key checks via `last_srcmap` cache before hash set insertion. - Replace line-start scanning implementation with a byte-slice helper and add regression tests for CRLF and unicode-tail position tracking. Performance (local CodSpeed simulation, benchmark `swc_ecma_codegen bench -- es/codegen/large`): - `accesses`: `1,875,783 -> 1,697,628` (`-9.50%`) - `estimated_cycles`: `2,602,923 -> 2,426,728` (`-6.77%`) Checks run: - `git submodule update --init --recursive` - `cargo fmt --all` - `cargo clippy --all --all-targets -- -D warnings` - `cargo test -p swc_ecma_codegen` **BREAKING CHANGE:** - None. **Related issue (if exists):** - None.

main

21 hours ago

perf(ecma_codegen): speed up JsWriter position and srcmap tracking

hardfist:perf/micro-optimize-swc-ecma-codegen

1 day ago

Latest Branches

+2%

fix(ts/fast-strip): reject unsafe assertion erasure in binary expressions#11828

22 days ago

48ac30b

magic-akari:fix/type-strip-assertions

+10%

perf: speed up swc_ecma_codegen JsWriter hot path#11870

20 hours ago

5145cc0

hardfist:codex/ecma-codegen-10pct-speedup

0%

perf(es/codegen): remove JsWriter last_srcmap cache#11869

20 hours ago

7d1baea

magic-akari:chore/ecma-codegen

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