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From: Jacob Sparre Andersen <sparre@nbi.dk>
Newsgroups: comp.lang.ada
Subject: GNAT, aggregates and efficiency (Was: Use aggregates)
Date: Tue, 12 May 2009 07:58:42 +0200
Organization: Jacob Sparre Andersen
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Date: 2009-05-12T07:58:42+02:00
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<simon.j.wright@mac.com> wrote:

> Someone recently found it was quicker to test an array for some
> condition by looping through it rather than by comparing with an
> aggregate [eg X = (others => 0)]. I had naively assumed that GNAT
> would just do the comparisons of the elements of X against 0, as the
> hand-crafted loop does, rather than construct a whole array of zeros
> on the stack and then loop through that ...

With which command line arguments and aggregate sizes is this the
case?

Greetings,

Jacob

PS: Never make premature local optimization!
-- 
"If I have to choose between two evils, I choose the one I
 haven't tried before."