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From: "T. Taft" <Tucker.Taft@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: Test tool not only for Ada
Date: Fri, 25 Jan 2008 20:57:46 -0800 (PST)
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Date: 2008-01-25T20:57:46-08:00
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On Jan 25, 4:31 am, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:
> On Fri, 25 Jan 2008 08:48:35 -0000, Stuart wrote:
> > The interesting challenge for 'Abstract Interpretation' tools is deciding
> > how much detail to preserve at each stage.  From the example should the tool
> > note that 'y' might have the values 2..40 or the set of values {2, 4, 6,
> > ..., 40}.
>
> > This can become important, for instance if you had the statement:
> >    z := 1000 / (y - 9);
>
> > Could a divide by zero occur?  If you had a lax model of 'y'  [2..40] you
> > would be concerned, but a more accurate model would dispel the concern.
>
> There is another difficult aspect of the problem of uncertain computations.
> It is dependency analysis. For example:
>
>    y := x;
>    z := x * y;
>
> When x is in [-1, 2] then without knowing that y equals x, i.e. assuming
> that x and y are independent, the best possible estimation of z is [-2, 4].
> With this knowledge it is [0, 4].

The SofCheck Inspector is another static analysis tool that
supports Ada.  We keep track of the kinds of symbolic
relationships you mention (such as X = Y) in addition
to pure value range information.

Our website is http://www.sofcheck.com

You might check wikipedia for "static analysis" or
"source code analysis".

>
> --
> Regards,
> Dmitry A. Kazakovhttp://www.dmitry-kazakov.de

Sincerely,
-Tucker Taft
SofCheck, Inc.
Burlington, MA  USA