[Ffmpeg-devel] int vs. float: Hard Numbers

[Loren Merritt]

On Fri, 20 May 2005, Rich Felker wrote:
> Yes, Intel sucks. Try it on AMD. FYI, test results I recently saw on
> #mplayerdev or one of the mailing lists (can't remember which right
> off) showed P4 taking 4x as many cycles to perform common codec
> operations as an Athlon took.

That was me, in #mplayerdev.

On a AMD Barton 1.8GHz:
428 dezicycles in h264_v_loop_filter_chroma_intra_mmx2, 1048576 runs

On a P4 2.3GHz:
1775 dezicycles in h264_v_loop_filter_chroma_intra_mmx2, 1048576 runs

That function has a couple of memory accesses, and is otherwise pure 
mmx 8-bit math.

--Loren Merritt