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From: "Martin Dowie" <martin.dowie@btopenworld.com>
Newsgroups: comp.lang.ada
Subject: Re: Optimizing Boundary Checks
Date: Fri, 13 Jun 2003 13:34:17 +0000 (UTC)
Organization: BT Openworld
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Date: 2003-06-13T13:34:17+00:00
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"Preben Randhol" <randhol+abuse@pvv.org> wrote in message
news:slrnbejegn.in.randhol+abuse@kiuk0152.chembio.ntnu.no...
> After reading some posts here lately I have understood that the compiler
> can optimise out boundary checks on say arrays if you do this:

Keyword in the last line is 'can'. I've run across compilers that
will do no optimization (i.e. leave checks in) on code such as:

   for I in My_Type loop
      Make_Call(My_Array (I));
   end loop;

but would take them out if written:

   for I in My_Array'Range loop
      Make_Call(My_Array(I));
   end loop;

Not sure if the checks in the first example would have
disappeared if we'd been allowed to switch compiler
optimizations on...

I guess the you just have to get that assembler listing and
check what each compiler you use does!