Hi.

There appears to be that besides GCC, there is PGCC: a Pentium specific 
compiler that does more optimizing than what the regular GCC does, specifically 
designed for optimizing code for Pentium processors. Quoting:

~~~~~~
I found a replacement compiler for GCC that did Pentium Optimizations 
(PGCC). The compiler used by [someone] is based on the same compiler source that 
PGCC is based on (GCC), however it doesn't have all the optimizations that are 
in PGCC.
~~~~~~

You can check http://www.goof.com/pcg/.

Andres.