[vlc-devel] The "optimized" memory copies

Rafaël Carré rafael.carre at gmail.com
Thu Aug 20 02:40:35 CEST 2009

On Wed, 19 Aug 2009 22:01:51 +0300
"Rémi Denis-Courmont" <remi at remlab.net> wrote:

> 	Hello,


> It turns out that vlc_memset() was about 2% slower than plain
> memset()... so I kinda wonder why we bother with implementing it.
> But then, vlc_memcpy() was an outrageous 35% slower than plain
> memcpy() on no- first pass, and 200% (three times, yes!) slower on
> the first pass. Sorry but WTF?

It probably was useful some years ago, but now I think the various libc
(and gcc?) use fast implementations.

The (Fucking Fast?) ffmpeg has no custom routine for these.

Note you'd probably want to test the routines on altivec, but I think
there is no point in checking the MMX (no SSE) routine.

OK for removal

Rafaël Carré
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