[Ffmpeg-devel] [PATCH] dead code elimination

[Aurelien Jacobs]

On Sat, 24 Feb 2007 18:35:48 +0100
Michael Niedermayer <michaelni at gmx.at> wrote:

> Hi
> 
> On Sat, Feb 24, 2007 at 02:05:24PM -0300, ramiro at lisha.ufsc.br wrote:
> > Dead since r1029
> 
> rejected, resurrect and benchmark it rather

I've just benchmarked it on amd64. For this, I've just disabled SIMD and
used START/STOP_TIMER around idctRowCondDC().
Results without FAST_64BIT:
  567 dezicycles in fast64bits, 1048564 runs, 12 skips
with #define FAST_64BIT:
  516 dezicycles in fast64bits, 1048570 runs, 6 skips
I've repeated the test with several videos and got similar results.

So defining FAST_64BIT on amd64 (and probably other 64bits arch) is
definitely a win.
I guess I should commit attached patch ?

Aurel
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