Hi Stefan, is this a benchmark program or a complex program you are talking about. If it is a benchmark, then it would be interesting to see the code, because from my experience I doubt that Delphi produces better code than fpc (in general it is the other way round). If it is a complex program, then you need to analyze carefully which part of the program consumes the most time and why. A number of 50% is in anyway unrealistic (this is something you get if you compare inlined code against uninlined) , because the differences you get from code optimization are in a range from +/-10% normally - unless you have found a real performance bottleneck. And sometimes (most of) it is only an unoptimized library code.
Adrian. On 21.09.2010 16:39, stefan...@web.de wrote: > Hi all, > > I am currently trying to get the fastest possible code from fpc on a modern > CPU (Intel Xeon) under Windows XP. I use the compiler options: > > fpc -Mdelphi -O3 -OpPENTIUMM -Cfsse2 -Cr- -Co- -CO- -Ci- myprogram.dpr > > Are there any better settings I should use? Compiling exactly the same > program with Delphi7 results in 50% faster code. I understand that fpc does > not support the most recent CPUs, but neither does DELPHI 7. So what > optimizations are done by Delphi 7 that are not done by fpc and why is this > the case? > > Stefan > ___________________________________________________________ > Neu: WEB.DE De-Mail - Einfach wie E-Mail, sicher wie ein Brief! > Jetzt De-Mail-Adresse reservieren: https://produkte.web.de/go/demail02 > _______________________________________________ > fpc-pascal maillist - fpc-pascal@lists.freepascal.org > http://lists.freepascal.org/mailman/listinfo/fpc-pascal _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
