Count leading zeroes a few bytes at a time - #126
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`QUICFrame.countZeroes()` shows up in a few benchmarks as 1.5% of CPU usage. It can be made a little faster by loading and checking 8 bytes at a time. For long runs of zeros (1200) it's ~4.5x faster, for very short runs (< 8) it's no worse.
glbrntt
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| while offset < count, bytes[offset] == 0x00 { | ||
| offset &+= 1 | ||
| } |
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Is this for trailing bytes?
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Yes: the first while loop does chunks of 8 bytes, this does the final up-to 7 seven bytes.
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Thank you @glbrntt !
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QUICFrame.countZeroes()shows up in a few benchmarks as using ~1.5% of CPU. It can be made a little faster by loading and checking 8 bytes at a time. For long runs of zeros (1200) it's ~4.5x faster, for very short runs (< 8) it's no worse.