Optimizations

["David M. Ronis" <ronis at ronispc dot chem dot mcgill dot ca>]

There's been some disccussion of egs vs gcc vs MSC benchmark results
on comp.os.linux.development.apps recently, much of which ends up with
various suggestions of what compiler flags should be specified.  For
example, one poster suggests:

gcc -O6 -mpentium -fomit-frame-pointer -fexpensive-optimizations \
>-ffast-math

To that, add:
        -march=pentium
        -fschedule-insns
        -fschedule-insns2
        -fregmove
        -fdelayed-branch

According to the gcc info description, all the -f options are enabled
(if supported) when -O2 (and I presume -O6) is specified.  Is this
correct?  

To the above I normally add the following:

-malign-double -malign-loops=0 -malign-jumps=0 -malign-functions=0\
-mno-ieee-fp 

Are the -malign directives implied by -march=pentium? (they probably
should be, and in either case, this sould be described in the info
pages).

Is -mno-ieee-fp implied by -ffast-math?


David Ronis