[pulseaudio-discuss] [PACKAGERS] Potential problem with MMX optimised volume code.

[Colin Guthrie]

Hi,

I'm not completely 100% sure about this yet (had one confirmation of it, 
but waiting for two others to get back to me), but I've been tracking a 
problem relating to SIMD for a while in:
https://qa.mandriva.com/show_bug.cgi?id=53870

It's hardware dependant and my hardware is not affected, but with some 
interactive session today, I was able to work with someone to narrow 
down the problem.

It *seems* that pa_volume_func_init_mmx() is to blame. Not calling this 
seems to address the issue. This will only affect those users with MMX 
but without SSE2. IOW, with this call commented out, non-SSE2 users will 
use an unoptimised (but working!) code path.

Here's a handy patch for you until I can say for sure what the problem 
is (e.g. my two other users confirm the "fix").
http://svn.mandriva.com/cgi-bin/viewvc.cgi/packages/cooker/pulseaudio/current/SOURCES/0505-mmx-Disable-pa_volume_func_init_mmx-for-now-as-it-se.patch?view=markup


wtay, if there is anything I can do to help you debug please shout!

Col

-- 

Colin Guthrie
gmane(at)colin.guthr.ie
http://colin.guthr.ie/

Day Job:
   Tribalogic Limited [http://www.tribalogic.net/]
Open Source:
   Mandriva Linux Contributor [http://www.mandriva.com/]
   PulseAudio Hacker [http://www.pulseaudio.org/]
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