[patch] tuning gcc for Intel Core2

[Andi Kleen]

> I tried these parameters and got better results (although I don't 
> remeber exact numbers).  Actually I've tried all parameters.  I started 
> the work when intel's guide was not public so I had to try all parameters.
> 
> Even if Core2 has special hardware to decrease problem of dependencies 
> on stack pointer, it does not mean that usage of push/pop will be better.

According to the guide PUSH has latency 1.5 (whatever that means) 
and MOV 1. No extra dependencies on the stack pointer because those
are optimized away early in the pipeline.

The advantage would be smaller code.

-Andi