[Ffmpeg-devel] [PATCH] SSE counterpart of ff_imdct_calc_3dn2

Rich Felker dalias
Thu Aug 24 06:35:50 CEST 2006

On Thu, Aug 24, 2006 at 09:53:05AM +0800, Zuxy Meng wrote:
> Hi,
> 2006/8/23, Michael Niedermayer <michaelni at gmx.at>:
> >Hi
> >
> >ive no objections to the patch (i didnt had any to the earlier patch 
> >either)
> >i just still think the loops would be better in asm then for(){}
> I still insist that intrinsics help produce better code, at least on gcc4.

And I still insist that this statement is fundamentally false. Better
than what? Whatever code gcc generates with the intrinsics, you can
always generate the same or better code if you just write it yourself.
Intrinsics are also gcc4-specific and have the problem that
performance is subject to the whims (and bugs) of gcc, whose record is
very bad...


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