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From: Gautier <gautier.demontmollin@maths.unine.ch>
Subject: Re: fast computing with GNAT (?)
Date: 2000/04/07
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Date: 2000-04-07T00:00:00+00:00
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Reinert Korsnes wrote:

> The f77 version takes about 7.5 s and the Ada version takes
> about 38 s on my Linux/laptop.
> 
> The actual build commands are:
> 
> f77 -c -O4 -ffast-math -malign-double test1.f
> 
> and
> 
> gnatmake -O4 test1.adb

Ok. Try gnatmake -O4 -ffast-math -gnatp test1.adb

The -gnatp is essential (=pragma suppress(all_checks))
to compare with Fortran!

In addition there are -funroll-loops, -fomit-frame-pointer,
etc. etc. to boost both G77 and GNAT. Maybe a -mpentium
is needed (otherwise GCC will think this is a 386!).

HTH
______________________________________________________
Gautier  --  http://members.xoom.com/gdemont/gsoft.htm