Comment Re:Bit-rot? (Score 1) 167
Incidentally, it's (probably) not in this case that the code was sub-optimal, just mis-optimized. Whether it's something like code written before AVX2 existed, now adding AVX2 codepath, or scenarios with two algorithms that end the same way that use different operations where a choice was made based on chips that could do one of those faster, and newer chips started getting faster the other way.