Date: Tue, 9 Mar 1999 17:53:12 +0100 To: pgcc AT delorie DOT com Subject: Re: gcc-2.7.0 creates faster code than pgcc-1.1.1 Message-ID: <19990309175312.G2217@cerebro.laendle> Mail-Followup-To: pgcc AT delorie DOT com References: <199903022313 DOT RAA17721 AT mail DOT mankato DOT msus DOT edu> <19990303165906 DOT A4028 AT cerebro DOT laendle> <36DDD2C1 DOT 421DD4AF AT t-online DOT de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <36DDD2C1.421DD4AF@t-online.de>; from Hans-Peter Jansen on Thu, Mar 04, 1999 at 01:24:33AM +0100 X-Operating-System: Linux version 2.2.2 (marc AT cerebro) (gcc driver version pgcc-2.93.04 19990131 (gcc2 ss-980929 experimental) executing gcc version 2.7.2.3) From: Marc Lehmann Reply-To: pgcc AT delorie DOT com X-Mailing-List: pgcc AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk On Thu, Mar 04, 1999 at 01:24:33AM +0100, Hans-Peter Jansen wrote: > > # pgcc fail: > # -fcompare-elim -floop-after-global -fcombine-222 > > all at the expense of a significant bigger binary. > > This really desillusionized me about the capabilities of all this > funky optimizing stuff... Mostly they are not worth the bigger size > they need (and the time figuring out the best switches). > > Real optimisation happens in the design phase of a project. > The compiler can help you getting the most of it! > > Correct me, if I'm wrong. > > Sorry, Marc. Please don't feel offended. As I'm an optimist, I will > look forward and see, how I can help you to get behind it... I don't feel offended, but on which CPU did you do your tests? My slackware 1995 binary runs significantly slower on my machine (p-ii) than the pgcc compiled ones, that is with current pgcc as well as the old libc5 binary that we happen to have on our homepage. This is with the snapshot pgcc, btw. The release might have some hand-tuning to be correct rather than fast in some cases. -- -----==- | ----==-- _ | ---==---(_)__ __ ____ __ Marc Lehmann +-- --==---/ / _ \/ // /\ \/ / pcg AT goof DOT com |e| -=====/_/_//_/\_,_/ /_/\_\ XX11-RIPE --+ The choice of a GNU generation | |