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From: Robb.Nebbe@di.epfl.ch (Robb Nebbe)
Subject: Re: GNAT function calling overhead
Date: 1995/04/06
Message-ID: <1995Apr6.163740@di.epfl.ch>#1/1
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sender: nebbe@lglsun3.epfl.ch (Robb Nebbe)
references: <3m0nv1$pv2@nef.ens.fr> <3m0psq$fl2@stout.entertain.com>
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organization: Ecole Polytechnique Federale de Lausanne
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Date: 1995-04-06T00:00:00+00:00
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In article <3m0nv1$pv2@nef.ens.fr>, Duncan Sands <sands@clipper.ens.fr> wrote:
>PS: The corresponding C code takes about 6 seconds.  This surprises
>me too.


The main reason is most likely that the Ada code is not at all equivalent
to the C code.

If you declare

type Matrix is array( 0 .. 14, 0 .. 14 ) of Float;

and write the loops in a way that allow the compiler to optimize out
the bounds checks (not sure if GNAT does this) then you should get
the same result as with C;


Robb Nebbe