X-pop3-spooler:	POP3MAIL 2.1.0 b 4 980420 -bs-
Message-Id:	<m0zEBKp-0000FVC@chkw386.ch.pwr.wroc.pl>
Date:	Wed, 2 Sep 98 11:44
From:	strasbur AT chkw386 DOT ch DOT pwr DOT wroc DOT pl (Krzysztof Strasburger)
To:	beastium-list AT Desk DOT nl
Subject:	pgcc-1.1a - first impression
Sender:	Marc Lehmann <pcg AT goof DOT com>
Status:	RO
X-Status:	A
Lines:	27

Hi!
I just downloaded and compiled pgcc-1.1a and did a simple comparison
with the older pgcc-1.0.3a (my own FPU-intensive program).
Compilation options:
-march=pentium -mcpu=pentium -On -ffast-math -frerun-loop-opt
-malign-double -mstack-align-double -malign-jumps=0 -malign-loops=0
-malign-functions=0,
where n=2,3,4 or s
The first thing I noticed is code bloat :-(, but this is rather egcs
related problem. Here are file sizes (in bytes):
pgcc-1.0.3a: -O2    -O3    -O4
             46600  46920  48024
pgcc-1.1a: -O2    -O3    -O4    -Os
           47880  48296  49224  46888
The second thing I noticed is no speed improvement on Pentium :-(((
(this is valid for tested program only, of course).
And now the good news. The optimization on Pentium Pro is better than before.
Here are execution times (only -mcpu=pentiumpro -march=pentiumpro different
than in previous example) averaged over 9 runs:
pgcc-1.0.3a:  -O2     -O3
              28.24s  28.95s
pgcc-1.1a     -O2     -O3     -Os
              28.45s  27.97s  28.12s
The performance win is not very big, but higher optimization options 
improve the performance for newer pgcc instead of degrading it.
The code optimized for size performs surprisingly well.
Krzysztof

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