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From: "Nick Roberts" <Nick.Roberts@dial.pipex.com>
Subject: Re: Pointer Arithmetic (was: Wanted: Ada STL....)
Date: 1999/02/03
Message-ID: <798lej$69d$1@plug.news.pipex.net>#1/1
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Newsgroups: comp.lang.ada
Date: 1999-02-03T00:00:00+00:00
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All unnecessary, Adam. Nowadays, (most) optimising compilers do what you
suggest automatically, without the need for a pragma.

A loop of the kind

   for i in 1..10 loop
      a(i) := b(i) + c(i);
   end loop;

will be compiled as if you had written

   xyz *pa = &a[0];
   xyz *pb = &b[0];
   xyz *pc = &c[0];
   <10 times>{ *pa++ = *pb++ + *pc++; };

and is also likely to have loop unrolling, instruction scheduling, and lots
of other things, applied, all to speed up your humble loop.

-------------------------------------------
Nick Roberts
-------------------------------------------

adam@irvine.com wrote in message <797na3$obg$1@nnrp1.dejanews.com>...
[...]
|Pointer arithmetic can be efficient when you're trying to
|step through an array, since you don't have to keep multiplying an index by
a
|constant value to access the array elements.
[...]