<bit>: Remove tzcnt special case for small integers in countr_zero #1540
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sylveon
changed the title
Micro-optimization ftw
StephanTLavavej
requested changes
Dec 17, 2020
AlexGuteniev
approved these changes
Dec 17, 2020
miscco
reviewed
Dec 17, 2020
cbezault
suggested changes
Jan 4, 2021
…-zero-small-int
cbezault
approved these changes
Jan 7, 2021
StephanTLavavej
approved these changes
Jan 9, 2021
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Thanks for improving the performance of these functions, and for verifying the before-and-after codegen! 🚀 😸 |
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Fixes #1534
This moves the check for
tzcntinside theelsecase, improving codegen for small integer types (shortandchar)Here's a Godbolt sample comparing the assembly output before and after: https://godbolt.org/z/K6nz8z