[Pixman] [PATCH] Add forgotten _mm_empty() calls in the SSE2 fetchers.

Soeren Sandmann sandmann at cs.au.dk
Fri Feb 18 00:32:21 PST 2011

Siarhei Siamashka <siarhei.siamashka at gmail.com> writes:

> I just wonder whether you have investigated why these missing _mm_empty() calls
> are not actually causing pixman tests failure? Is it because fetch operation is
> typically followed by combiner which has _mm_empty()? But SRC combiner should
> not be using MMX/SSE2. Or no MMX instructions are actually used by these
> fetchers (only SSE2)?

It's because these fetchers don't use any MMX instructions, so the
patch is actually pointless. I'll drop it.

It may even be worth considering just dropping all MMX instructions
from the SSE2 implementation. That would avoid all the emms related
problems. The places where we use MMX instructions could just as well
use SSE2 - we never take advantage of the fact that it is possible use
both SSE and MMX registers at the same time.


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