better optimization flags for opteron (amd64)// -ffast-math and -O3 are not friends

[Toll, Eric]

 15834270 = g++ dual operon 242's @ 1.6Ghz ea. default
compile




> -----Original Message-----
> From: owner-freebsd-amd64 at freebsd.org 
> [mailto:owner-freebsd-amd64 at freebsd.org] On Behalf Of 
> Olexandr Konovalenko
> Sent: Tuesday, July 19, 2005 11:26 AM
> To: freebsd-amd64 at freebsd.org
> Subject: Re: better optimization flags for opteron
(amd64)// 
> -ffast-math and -O3 are not friends
> 
> hi!
> 
> I found that on my system combination of -ffast-math AND
-O3 
> is slower than -O0 on AMD64 (interestingly it is true for 
> Xeon EM64 as well), how can it be?

Also true for Opteron.

My Score was: 15834270 = g++ dual operon 242's @ 1.6 default
compile options, -O3 was 14944704

Interesting program, now *who/what* can beat the score of:
20152707 ????

(Post cpu specs please, I like to see an SMP Opteron 248
score...)