8 Sep
2011
8 Sep
'11
2:59 a.m.
On Wed, 7 Sep 2011, Mathieu Bouchard wrote:
On Wed, 7 Sep 2011, Bill Gribble wrote:
So far iteration on plain floats seems to be the best I can come up with, but HADDPS is tantalizingly close to what I want to do. Any hints?
Once I thought that with some commutativity you could speed things up like this :
(f0+f1+f2+f3)+(f4+f5+f6+f7)+...
can be rearranged as :
(f0+f4+...)+(f1+f5+...)+(f2+f6+...)+(f3+f7+...)
But what I said does not apply to your case, because you want a scan, whether I didn't really read and assumed a fold.
I don't know how to optimise a scan.
| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC