store ascii start/continue bitmaps in u128 instead of slices of bool#40
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dtolnay merged 1 commit intodtolnay:masterfrom Oct 21, 2025
Merged
store ascii start/continue bitmaps in u128 instead of slices of bool#40dtolnay merged 1 commit intodtolnay:masterfrom
dtolnay merged 1 commit intodtolnay:masterfrom
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Reduce execution time by 44% in 0%-nonascii case and by 32% in 10%-nonascii. Reduce the static data size ~200 bytes.
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Tested also on Apple M1 with a time reduction around 20-30% |
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Hello @dtolnay, do you have any feedback about this? |
dtolnay
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Oct 21, 2025
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Thank you! This is an extraordinary performance improvement.
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Hello,
Using slices of bools to store ASCII CONTINUE and START data results in using 2*128 bytes of memory since one entire byte is used to store each boolean.
Since ASCII chars are 128, bitmaps fit perfectly in u128 consts.
This change reduces execution time by 44% in 0%-nonascii case and by 32% in 10%-nonascii, according to the crate's benches, and reduces the static storage by ~200 bytes.
Benchmarks were run on an Intel i5-12400 system.
Thanks