[Pixman] bilinear fast path

[Alexander Larsson]

On Mon, 2010-03-15 at 17:05 +0200, Siarhei Siamashka wrote:
> On Monday 15 March 2010, Alexander Larsson wrote:
> > On Fri, 2010-03-12 at 16:18 +0100, Alexander Larsson wrote:
> > > > I took this as a base and created a new branch that does fast
> > >
> > > scaling,
> > >
> > > > achieving similar performance, and passing scaling-test.
> > >
> > > http://cgit.freedesktop.org/~alexl/pixman/log/?h=alex-scaler
> >
> > Based on this i also made a simple 8888 bilinear scaler. I get
> > performace changes like:
> >
> > From:
> > Scaling from 640x480 to 1152x864 in 13467 usec
> > To:
> > Scaling from 640x480 to 1152x864 in 11031 usec
> >
> > And even more for smaller scaling. Not extraordinary, but still a
> solid
> > gain.
> 
> Really good performance improvements for bilinear scaling are going to
> come
> from SIMD optimizations. To make it happen, scaler core needs to be
> isolated
> into a small simple function with a minimal number of checks and
> branches.

http://cgit.freedesktop.org/~alexl/pixman/commit/?h=fast-bilinear&id=a79daa8453560b4193b848e51b4942dcdcd74c8d

The "/* Main columns: */" part there is probably a good start for that.


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 Alexander Larsson                                            Red Hat, Inc 
       alexl at redhat.com            alexander.larsson at gmail.com 
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