[Bug tree-optimization/57534] [6/7/8 Regression]: Performance regression versus 4.7.3, 4.8.1 is ~15% slower

[amker at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57534

--- Comment #25 from amker at gcc dot gnu.org ---
(In reply to Aldy Hernandez from comment #23)
> (In reply to amker from comment #22)
> 
> > > So my suggestion would be to see if you can make SLSR generate
> > > TARGET_MEM_REFs
> > > based on some common infrastructure with IVOPTs.
> > Yes, I also believe strength reduction infrastructure in IVOPTs could be
> > (easily?) extended to cover this case.  Either export interface from IVOPTs
> > and do it in SLSR etc., or simply handle such loops specially in IVOPTs it
> > self.  Then it would be something like vect vs slp.  I have time now and can
> > play with this idea.
> 
> Bin, do you want to take over the PR?

Yes, I can study the IVOPTs part.  Though not sure if this PR reveals
opportunities in other passes or not.  Thanks