Re: Worst Case Execution Time Tool?

[Stuart Palin <stuart.palin@baesystems.com>]

Ted Dennison wrote:

> In article <3C0D536C.2E059EE8@computer.org>, StationSteve says...
> >Are there any tools that quantitatively determine the worst case
> >execution time (WCET) of an Ada83 program or subprogram?

> Wouldn't such a tool also be able to solve the Halting Problem? (
> http://foldoc.doc.ic.ac.uk/foldoc/foldoc.cgi?query=halting+problem )

<simple answer>
No!
</simple answer>

If a WCET tool was developed on general terms with the intention of
dealing with all forms of program, then it is most likely that if a
non-terminating program was submitted for analysis the analysis itself
would not halt.

In more practical terms, this type of tool will typically constrain the
types of program that it will analyze.  Typically this might prohibit
recursion and demand upper limits for loops to be statically
determinable (either from the code or from annotations).  Such rarified
problems as the Halting Problem are hardly a consideration.

--
Stuart Palin
Principal Software Engineer
BAE SYSTEMS Avionics Ltd, Rochester
G-NET 791 3364    mailto:stuart.palin@baesystems.com