[FFmpeg-devel] [PATCH 2/2] Don't use CMOV in MMX code
h.leppkes at gmail.com
Sat Sep 13 00:27:42 CEST 2014
On Fri, Sep 12, 2014 at 11:53 PM, Daniel Kang <daniel.d.kang at gmail.com>
>>All processors supporing mmx2 also support cmov, so if a test for mmx2
> succeeds, we can use cmov.
> Since I originally thought mmx => cmov (and apparently am wrong) is there
> official documentation supporting this?
CMOV was introduced in the P6 architecture, which is Pentium Pro, or i686.
MMX came before in P5 already ("Pentium with MMX Technology")
Its probably in Intel's Software Developer’s Manual somewhere, but I
couldn't find it on a moments notice, only the instruction sets like
MMX/SSE/... are listed very prominently.
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