-freduce-all-givs differs on P3 and P4

[tm_gccmail@kloo.net]

On Thu, 23 Oct 2003 tm_gccmail@kloo.net wrote:

> On Wed, 22 Oct 2003, Scott Robert Ladd wrote:
> 
> > I made an odd discovery (at least in my mind) whilst exploring evolution 
> > in different environments... consider these two command lines:
> > 
> >      A) gcc -lm -lrt -march=pentium3 \
> >          -O3 \
> > 	-o lpbenchA lpbench.c
> > 
> >      B) gcc -lm -lrt -march=pentium3 \
> > 	-O3 -freduce-all-givs \
> > 	-o lpbenchB lpbench.c
> > 
> > "B" runs 23.5% faster than "A" on a Pentium 3, due to the addition of 
> > -freduce-all-givs. A very nice improvement.
> 
...

Do you have any other benchmarks which exhibit anomalous behavior besides
the lpbench which you sent me?

Toshi