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
Lines:	17
Message-ID:	<365DF194.2A2098C@dds.nl>
References:	<199811262004 DOT UAA00490 AT remus DOT clara DOT net>
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To:	djgpp AT delorie DOT com
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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

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