[FFmpeg-devel] [PATCH] some SIMD write-combining for h264

Alexander Strange astrange
Sat Jan 16 05:11:23 CET 2010


This adds intreadwrite macros for 64/128-bit memory operations and uses them in h264.

Unlike the other macros, these assume correct alignment, and the patch only defines the ones there was an immediate use for.
This only has x86 versions, but others should be easy. The 64-bit operations can be done with double copies on most systems, I guess.

Decoding a 30s file on Core 2 Merom with --cpu=core2 (minimum of 5 runs):
x86-32: 12.72s before, 12.51s after (1.7%)
x86-64: 10.24s before, 10.20s after (.4%)

Tested on x86-32, x86-64, x86-32 with --arch=c.

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