[theora-dev] SSE2 assembly support

[Timothy B. Terriberry]

Kay Tiong Khoo wrote:
> The profile concurs with Timothy's assessment. The optimized MMX functions account for ~30% of the samples, so the room for improvement by conversion to SSE2 is limited. I will try some opportunistic optimizations before starting on the conversion work. 

Make sure you are working from the current 1.2 development branch:
http://svn.xiph.org/experimental/derf/theora-ptalarbvorm/

On x86-64, this should be using SSE2 already for SATD (your profile
shows the MMXEXT versions). It still uses MMXEXT SATD on x86-32 because
the SSE2 versions profiled as slower on an actual 32-bit processor
(where each instruction often requires multiple clocks).