https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62011
finis at in dot tum.de changed:
What |Removed |Added
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CC| |finis at in dot tum.de
--- Comment #4 from finis at in dot tum.de ---
> Not sure if we want to
> disable popcnt use completely.
No matter how to fix this, do not disable popcnt! Even with the false
dependency it is still the fastest instruction for popcounting. The false
dependency makes it slower, but it is still faster than a hand written version.
The easiest fix IMHO would be using xor %r %r on the output register. It seems
to work extremely well, as you can see in the answer of the linked SO question.
