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Mail Archives: djgpp/1998/09/12/10:53:36

Reply-To: <arfa AT clara DOT net>
From: "Arthur" <arfa AT clara DOT net>
To: "DJGPP Mailing List" <djgpp AT delorie DOT com>
Subject: RE: PGCC
Date: Sat, 12 Sep 1998 15:45:21 +0100
Message-ID: <000901bdde5b$f7832840$f54e08c3@arthur>
MIME-Version: 1.0
In-Reply-To: <Pine.GSO.3.96.980911174820.3315A-100000@eduserv2.rug.ac.be>
Importance: Normal

> Hi. I have been using PGCC for compiling both C and C++ for several months
> now, and I haven't had much problems. I also compiled Allegro with PGCC,
> wich gave me an average of +-5% speedup in general for my Allegro
> programs. If i compile my programs themselves with the -mpentium -O6
                                                         ^^^^^^^^^
-mpentium is a gcc 2.8.1 command, not a pgcc command.

> options I get an additional 5% to 10% speedup. (the speedup was measured
> by an increase in framerates, this might be somewhat imprecise, althoug an
> increase from 60 FPS to 80 FPS in one of the programs seems very
> significant.) IIRC you must get the libc sources and recompile them, at
> least for some versions of the libc library. You should check the readme
> files of the PGCC compiler for more info. Also, it seems that the C++ PGCC
> is better than the normal version, although i have no means of comarison
> as I replaced the standard DJGPP c++.

No, pgcc's version is currently older than the latest release of DJGPP.
Especially the C++ compiler.

> PGCC is
> in my honest opinion really worth the effort of getting it to work!

Not so in my case. -mpentium -march= and =mcpu= commands along with -O3 and
a couple of other optimisations (all gcc 2.8.1) gave me a speed increase of
about 10% on average. Pgcc's-O6/-O7 gives me a speed decrease of between
25-50% on average.

James Arthur
jaa AT arfa DOT clara DOT net
ICQ#15054819

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