[Liboil] Liboil slower than plain gcc?

Robert Schwebel r.schwebel at pengutronix.de
Sun Dec 16 04:46:41 PST 2007


On Sat, Dec 15, 2007 at 01:30:47PM -0500, Jason Sewall wrote:
> On Dec 15, 2007 1:18 PM, David Schleef <ds at schleef.org> wrote:
> > On Sat, Dec 15, 2007 at 01:08:51PM -0500, Jason Sewall wrote:
> > > it ends up being about 3-4x slower than gcc with this:
> > > for(int i = 0; i < size; ++i)
> > >      dest[i] = c1*src1[i]+c2*src2[i];
> > >
> > > If they are compiled with:
> > > -DNDEBUG -O3 -funroll-all-loops -march=prescott --std=c99 -msse3 -mfpmath=sse
> > >
> > > Am I doing something grossly wrong?
> >
> > Yes, you're assuming that someone has bothered to write optimizations
> > for that function.
>
> Got it. I'll stick with GCC.

Well, you could also write an optimization and provide a patch :-)

rsc
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
   Handelsregister:  Amtsgericht Hildesheim, HRA 2686
     Hannoversche Str. 2, 31134 Hildesheim, Germany
   Phone: +49-5121-206917-0 |  Fax: +49-5121-206917-9



More information about the Liboil mailing list