[cairo] [RFC] altivec optimization

[Luca Barbato]

I'm writing optimizations for altivec, basically processing 4 pixels at
time, the problem is that I have to call back the scalar version to
finish the processing in case the width isn't multiple of 4.

Which is the best course of action? straight copy the scalar code inside
 the vector functions or call the scalar function passing the remaining
pixels?

I'll try to provide a working patch soon, for now the source is just a
testcase that compares scalar and vector function outputs.

http://dev.gentoo.org/~lu_zero/development/fbaltivec.c

lu