Optimizing a compiler?

[Paul Furness <paul.furness@vil.ite.mee.com>]

Sorry, this might be a little bit OT, but can anyone point me at some
useful info about how to compile code so that it uses the best speed
features of a given type of CPU?

I know that I can recompile the _kernel_ for and Athlon processor or an
intel P4 etc, but how do I optimize my own code which has nothing to do
with the kernel?

Do I need to change the code itself, or can I give gcc (in this case
g++) some options that tell it to use the best possible number crunching
code for my Athlon servers?

We're doing some research into video pattern recognition, so need to get
the absolute maximum possible number munching from our servers as a
single run take us at least 18 hours; every saved clock cycle adds up.

Thanks.

Paul.

-- 
Paul Furness

Systems Manager

2+2=5 for extremely large values of 2.