Hi,
On Sun, Mar 27 2011, Gordan Bobic wrote:
On 03/27/2011 04:19 AM, Chris Ball wrote:
> I suspect you're right that recompiling the world with NEON is no big
> deal, but simply doing glibc/X/liboil/codecs should be a large win by
> itself. In those cases there's pre-vectorized code sitting there
> and waiting to be emitted once the right flag's turned on.
If there is such code in there (and I'm not convinced there is much, if
any), it is likely to be hand-crafted assembly - and if that is the
case, it's a virtual certainty that it isn't ARM assembly.
You are wrong. Here is a patch for NEON-optimized memcpy() for glibc
written in ARM assembly:
http://sourceware.org/ml/libc-ports/2009-07/msg00003.html
Orc¹, which replaced liboil in gstreamer, also emits NEON asm:
http://code.entropywave.com/git?p=orc.git;a=blob;f=orc/orcrules-neon.c
As does pixman, which accelerates X rendering and reports simple
fill/blit operations being at least twice as fast with NEON:
http://sandbox.movial.com/blog/2009/06/pixman-gets-neon-support/
- Chris.
¹:
http://code.entropywave.com/projects/orc/
--
Chris Ball <cjb(a)laptop.org> <
http://printf.net/>
One Laptop Per Child