[FFmpeg-devel] [PATCH 2/2] Don't use CMOV in MMX code

[Calvin Walton]

On Fri, 2014-09-12 at 14:53 -0700, Daniel Kang wrote:
> > 
> > >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?
> 

As an example, here's the /proc/cpuinfo contents for my AMD K6 box. 
You'll note that on the flags line it does have 'mmx', but does not 
have 'cmov'. (It also doesn't have 3dnow; that was introduced in later 
chips in the K6 series.)

I'm actually looking into getting FATE running on this box right now, 
we'll see how that goes.

processor       : 0
vendor_id       : AuthenticAMD
cpu family      : 5
model           : 7
model name      : AMD-K6tm w/ multimedia extensions
stepping        : 0
cpu MHz         : 266.603
cache size      : 64 KB
fdiv_bug        : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 1
wp              : yes
flags           : fpu vme de pse tsc msr cx8 mmx
bogomips        : 533.42
clflush size    : 32
cache_alignment : 32
address sizes   : 32 bits physical, 32 bits virtual
power management:

-- 
Calvin Walton <calvin.walton at kepstin.ca>