On Tue, 6 Feb 2007, Dorit Nuzman wrote: > Ira Rosen/Haifa/IBM wrote on 06/02/2007 11:49:17: > > > Dorit Nuzman/Haifa/IBM wrote on 05/02/2007 21:13:40: > > > > > Richard Guenther <[EMAIL PROTECTED]> wrote on 05/02/2007 17:59:00: > > > > ... > > > > > > That's going to change once this project goes in: "(3.2) Straight- > > > line code vectorization" from http://gcc.gnu. > > > org/wiki/AutovectBranchOptimizations. In fact, I think in autovect- > > > branch, if you unroll the above loop it should get vectorized > > > already. Ira - is that really the case? > > > > The completely unrolled loop will not get vectorized because the > > code will not be inside any loop (and our SLP implementation will > > focus, at least as a first step, on loops). > > Ah, right... I wonder if we can keep the loop structure in place, even > after completely unrolling the loop - I mean the 'struct loop' in > 'current_loops' (not the actual CFG), so that the "SLP in loops" would have > a chance to at least consider vectorizing this "loop". Zdenek - what do you > say?
Well, usually if it's not inside another loop it can't be performance critical ;) At least if there would be a setup cost for the vectorized variant. I don't think we need to worry about this case until a real testcase for this comes along. Richard. -- Richard Guenther <[EMAIL PROTECTED]> Novell / SUSE Labs
