Article

Formal verification of SAM state machine implementation

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Abstract

This paper reports the results of an experiment about the formal verification of source code made according to an EMF model. Models define the semantics of a system whereas the source code defines its implementation. We applied this solution to a model of Automaton in SAM language and its C language implementation. The technical environment is close to an industrial operational context and all the tools are available. The experimentation has succeeded and has to be consolidated with bigger cases before an introduction in the operational development process. More generally, this solution must be extended to other model languages.

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... Notre approche se focalise sur la génération automatique des propriétés à vérifier sur le code à partir du modèle de conception afin d'obtenir une étape de vérification formelle entièrement automatisée d'un point de vue de l'utilisateur. Ce principe a déjà fait l'objet d'une expérience préalable par Atos à partir d'un langage dédié d'automate défini par Airbus [41]. Notre approche s'inscrit dans la philosophie de ces travaux mais intervient dans un contexte technique différent puisque nous allons travailler avec le langage de modélisation UML et plus précisément avec les machines à états UML qui sont particulièrement adaptées à la représentation comportementale de logiciel. ...
... D'autres ont exploré la génération automatique d'annotations à partir d'un modèle afin d'aboutir à une vérification formelle de la conformité d'un code source par rapport à sa conception. [41] propose un moyen d'annoter automatiquement un code C selon une spécification composée d'automates SAM 35 , en vue de sa vérification comportementale. SAM est un langage dédié pour la représentation comportementale de composants avioniques. ...
... Cependant, les contrats de fonction sont partiels, ils ne vérifient qu'une partie de la complétude de l'implémentation des transitions. 41. argouml.tigris.org ...
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Présentation du langage SAM d'Airbus
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