An Introduction to OTAWA
Clément Ballabriga
Université Paul Sabatier, Toulouse, France
OTAWA is a freeware application dedicated to the computation of the
WCET of programs. More precisely, OTAWA concerns the numerous WCET
approaches based on static analyses of the executable program. Unlike
many existing usual tools, the choice has been done to avoid
specialisation and to produce, instead, a generic and open framework.
WCET computation has always required to pass flow fact information from
the user to the computation analysis even with tools including loop
bound analyses. From the start of OTAWA and overmore with the use of the
oRange, OTAWA has developed a more and more extensible annotation
system based on XML file. In the last project, this annotation system
has been largely extended to embed timing information and user domain
definitions and to locate accurately information in the program and in
the execution time.
Biography:
Clément Ballabriga is a PhD student supervised by Hugues Cassé since
2006 and works on cache behavior, partial analysis and abstract
interpretation. He is a member of the TRACES team whose research
interests include hardware issues of real-time embedded systems. The
main goal is to guarantee that the execution time of an application
code meets the system deadlines. We focus on characterizing the
temporal properties of components off-the-shelves. Our target is to
propose ways to use these components such that safe and tight
worst-case execution time estimates can be computed. We also study
architectural extensions that should improve the time predictability
of the components. The estimation of the WCET requires three steps: a
static analysis of the code identifies all the possible execution
paths; the target hardware is modelled to determine the individual
execution times of the basic blocks; then, the results of the previous
steps are combined to evaluate an upper bound of the global execution
time. Part of our work concerns the first and second steps.
Contact Cllément at:
Clément Ballabriga, M.Sc.
Institut de Recherche en Informatique de Toulouse (IRIT)
Université Paul Sabatier
118 Route de Narbonne
F-31062 Toulouse, France
ballabri at irit.fr
http://www.irit.fr/recherches/ARCHI/MARCH/index.php3