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Re: [PATCH, i386]: Do not emit "cld" instructions


Jan Hubicka wrote:

Thanks,
it ineed makes rep;movsl quite a bit faster for small blocks!
Basically we should use rep;movsl on those machines almost always for
memcpy now, for memset rep;stosl wins after 48bytes up.
I am testing the attached patch I would like to commit as obvious if it
passes once CLD autogen is gone. I wonder how it changes povray
benchmarks?


With attached patch, I didn't measure any impact on the povray outside of the noise.

BTW: cld removal did show ~0.1s out of 14s better times.

Uros.


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