Re: For GNAT People

[Greg Bond <bond@ee.ubc.ca>]

grt wrote:

> snip...
> 
> In the last years greater and greater importance has been attributed
> to the non-functional requirements, in particular to the deadlines
> associated to time requirements. If such requirements are not faced
> very early in the software life-cycle, then the reliability of the
> developed system might be hardly affected.  Techniques have been then
> developed to be able to check that the deadlines are met even in the
> worst case of execution.  Tools that apply such techniques are called
> Schedulability Analyser.  They need a description of the system
> dynamic behavior and the execution time of pieces of sequential code.
> After the development phase it is easy to measure the required times,
> but we would like to be able to perform the analysis BEFORE all code
> is produced and without exercising the specific hardware. At this
> purpose it is needed a so called Worst Case Execution Time
> Analyser. It is a tool able to estimate with a high degree of
> confidence the execution time given the source code statements. My
> company's role includes the development of such a tool.
>
> snip...

I don't think anyone would disagree with the fact that WCET analysis
before all code is complete would be valuable, however I'm curious to
know how one can approach WCET analysis without having all the code
involved. Any approach I'm familiar with analyzes RTL, or byte code i.e.
the result of compiling (completed) code. Is some sort of incremental
approach possible?





--
* Greg Bond                         * Dept. of Electrical Eng.  
* email: bond@ee.ubc.ca             * Univ. of British Columbia      
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