From: DougEleveld <deleveld AT dds DOT nl>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: optimizations???
Date: Fri, 27 Nov 1998 01:25:56 +0100
Organization: Rijksuniversiteit Groningen
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References: <199811262004 DOT UAA00490 AT remus DOT clara DOT net>
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

Arthur wrote:

> -O6 is the main optimisation switch for PGCC - the pentium GCC compiler.
> People have had varying degrees of success with this. I have got about a 60%
> speed _reduction_ by using PGCC, and stick
> with -mpentium -mcpu=pentium -march=pentium and either -O2 or -O3 (depending
> on what the code is like).

Personally, I use -O2 -fomit-frame-pointer and -ffast-math. 
-march=pentium has
somtimes a quite dramatic speedup (or a minor slowdown).  -O3 seems to
really bloat
the code without all that much speedup, so I don't think it's worth it.
My experience 
with PGCC has been the same as you.

Doug Eleveld