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perf: faster float decoding with Eisel-Lemire and eight-digit runs #7

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perf: faster float decoding with Eisel-Lemire and eight-digit runs #7

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b14564e
perf: convert long floats with Eisel-Lemire instead of reparsing them
lalinsky Oct 17, 2026
dc51904
perf: read fraction digits eight at a time
lalinsky Oct 17, 2026
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1 change: 1 addition & 0 deletions CHANGELOG.md
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Expand Up @@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
### Changed
- Encoding writes straight into the writer's buffer when there is room, with the writer marked `noalias`, which makes encoding about 26% faster on a string-heavy document and 14% on a small message
- Integers are written straight into the writer's buffer, and strings shorter than 16 bytes are escaped inline, about another 5% on a string-heavy document and 8% on a small message
- Floats too long for the exact fast path, around 17 significant digits, are converted with Eisel-Lemire from the digits already collected instead of being parsed again by `std.fmt.parseFloat`, and fraction digits are read eight at a time, making decoding a float-heavy document about 20% faster

### Fixed
- Structs with a few dozen fields failing to compile with "evaluation exceeded 1000 backwards branches"
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