X-pop3-spooler: POP3MAIL 2.1.0 b 4 980420 -bs- Message-ID: <19980902171402.50556@cerebro.laendle> Date: Wed, 2 Sep 1998 17:14:02 +0200 From: Marc Lehmann To: Krzysztof Strasburger Cc: beastium Subject: Re: pgcc-1.1a - first impression Mail-Followup-To: Krzysztof Strasburger , beastium References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: ; from Krzysztof Strasburger on Wed, Sep 02, 1998 at 11:44:00AM +0000 X-Operating-System: Linux version 2.1.119 (root AT cerebro) (gcc version pgcc-2.91.54 19980816 (gcc2 ss-980609 experimental)) Status: RO Content-Length: 1929 Lines: 48 On Wed, Sep 02, 1998 at 11:44:00AM +0000, Krzysztof Strasburger wrote: > 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 Does -fno-exceptions help? > 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). Thats, erhm, bad. But did you try -O6, as the most effective optimization on pentiums is enabled with -O5 and higher only. Having said this, I have no idea what could have happened to pentium opts, as I can't remember changing them significantly ;( But the performance problems in egcs/pgcc I talked about in my earlier mail is mainly related to fpu-intensive programs... Could you try without the *align-double options? (just a guess) And maybe you could post your benchmark data with -O2,3,6? > And now the good news. The optimization on Pentium Pro is better than before. *sigh* > The code optimized for size performs surprisingly well. Could be better ;) inlining still bloats code (it shouldn't). Thanks, -----==- | ----==-- _ | ---==---(_)__ __ ____ __ Marc Lehmann +-- --==---/ / _ \/ // /\ \/ / pcg AT goof DOT com |e| -=====/_/_//_/\_,_/ /_/\_\ --+ The choice of a GNU generation | |