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makapuf
89 days ago
Compilers won't do multiplication by power of two to bit shift for you ? I remember reading in ~2000: the only thing writing a<<2 instead of a/4 will do is make your compiler yawn
1 comments
zekica
89 days ago
Even gcc's -O0 will do the bitshift, but even dividing with 5 on x86_64 will not do idiv:
imul rdx, rdx, 1717986919 shr rdx, 32 sar edx sar eax, 31 sub edx, eax mov eax, edx
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