<bit>: Remove tzcnt special case for small integers in countr_zero - #1540
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Stephan T. Lavavej (StephanTLavavej) merged 7 commits intoJan 15, 2021
Merged
<bit>: Remove tzcnt special case for small integers in countr_zero#1540Stephan T. Lavavej (StephanTLavavej) merged 7 commits into
Stephan T. Lavavej (StephanTLavavej) merged 7 commits into
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Micro-optimization ftw
Stephan T. Lavavej (StephanTLavavej)
requested changes
Dec 17, 2020
Alex Guteniev (AlexGuteniev)
approved these changes
Dec 17, 2020
Curtis J Bezault (cbezault)
suggested changes
Jan 4, 2021
…-zero-small-int
Charles Milette (sylveon)
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Stephan T. Lavavej (StephanTLavavej) and
Curtis J Bezault (cbezault)
January 6, 2021 01:50
Curtis J Bezault (cbezault)
approved these changes
Jan 7, 2021
Stephan T. Lavavej (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