[FFmpeg-devel] [PATCH] remove constant vector loads

Guillaume Poirier gpoirier
Wed Jun 13 16:47:22 CEST 2007

Here's a patch, contributed by Sigbj?rn Skj?ret that does $SUBJ.

"H.264 code is free of constant loads now, though neither being at
particularly critical places it probably won't make any difference..."

I'm not sure that it helps too much as you trade a constant vector
load (that has a chance to stay in the cache it you use it many times)
by more instructions that will be executed each time.

So I guess this deserves to be benchmarked on G4 (known for its anemic
FSB) and Cell (known to be sensible to different strategies than other
PPC due to its in-order arch).

I'll try to come up with benchmark figures on G5 later.

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