A 100LOC C impl of memset, that is faster than glibc's

Re:A 100LOC C impl of memset, that is faster than glibc's by BeeOnRope on Friday November 12, 2021 @09:24AM (#29199515)

Not the OP, but 16 has the benefit of keeping both pointers in the comparison 16-byte aligned if the buffer was initially aligned.

This would eliminate split loads and provide a decent speedup.

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Re:A 100LOC C impl of memset, that is faster than glibc's by boibombeiro on Saturday November 13, 2021 @03:27AM (#29208339)

This, and loop unrolling, are two commons misconception about uarch optimization.

Memory alignment is innocuous (others than often compromise code legibility).

Loop unrolling, on the other hand, can slow down the code. Specially in small loops.

See Agner uarch PDF.

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