[Ffmpeg-devel] [RFC] Addition of JIT accelerated scaler for ARM into libswscale

Michael Niedermayer michaelni
Tue Jan 23 15:27:29 CET 2007


Hi

On Tue, Jan 23, 2007 at 01:30:39PM +0100, Reimar Doeffinger wrote:
> Hello,
> On Tue, Jan 23, 2007 at 12:22:26AM +0200, Siarhei Siamashka wrote:
> [...]
> > A natural solution for getting good scaler performance is to use JIT style 
> > dynamic code generation. I spent full two days on the last weekend and got
> > some initial scaler implementation working (it is quite simple and
> > straightforward and uses less than 300 lines of code):
> > https://garage.maemo.org/plugins/scmsvn/viewcvs.php/trunk/libswscale_nokia770/?root=mplayer
> 
> What is the point of those four mprotects?? AFAICT at most you would
> want to do one mprotect at the end to remove the write permission, but
> if that is worth the extra dependency...

yes it is worth ... having executeable+writeable memory is not good

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I do not agree with what you have to say, but I'll defend to the death your
right to say it. -- Voltaire
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