[x264-devel] Detecting CPU capabilities

[Andreas]

Am Donnerstag, 18. September 2008 15:31:02 schrieb Jason Garrett-Glaser:
> On Thu, Sep 18, 2008 at 3:19 PM, Andreas <linuxdreas at dslextreme.com> 
wrote:
> > On my AMD X2 systems (Linux, x86_64), x264 shows this string when I
> > start encoding:
> > x264 [info]: using cpu capabilities: MMX2 SSE2Slow
> > Now, according to AMD, the X2 DualCore cpu is "Including support for
> > SSE, SSE2, SSE3, MMX™, 3DNow!™ technology and legacy x86 instructions"
> >
> > Do I have to tell x264 to use SSE3 somehow, and would that have any
> > advantage over the current autodetection?
>
> SSE3 isn't used because there is no use for it.  The only SSE3 code is
> used solely for the purpose of bypassing Intel's problem of cacheline
> splits, and only on a single line of CPUs that benefits (Pentium 4D).

That's what I use for my desktop pc. Kind of outdated, though.

> Now, if you can suggest a use of SSE3 besides that, we might
> investigate it, but we haven't noticed any other possible uses ;)

I feel technically advanced by having figured out how to compile x264, but 
other than that I'm in no position to suggest any code changes ;)

-- 
Gruß
Andreas