Simple and Efficient Translation from LTL Formulas to Büchi Automata

AbstractWe present a collection of simple on-the-fly techniques to generate small Büchi automata from Linear Time Logic formulas. These techniques mainly involve syntactic characterizations of formulas, and yet allow efficient computations. Thus heavily relying on such proof-theoretic issues, we can omit the classical formula pre-simplification step, and also simulation-based post-simplification steps (aka model-theoretic issues).Although closely related to other similar recent works in the same topic, our ideas have led to an implementation that performs significantly better than some of the best available tools, such as Wring or LTL2BA. We compare our tool BAOM (“Büchi Automata Once More”) with others, on formulas commonly found in the literature, and on randomly generated testbenchs

A Framework to Formalise the MDE Foundations

International audienceDomain-Specific Language (DSL) are getting more and more popular and are being used in critical systems like aerospace and car industries. Methods for simulating and validating DSL models are now necessary in order to make the new software generation more reliable and less costly. Developing analysis tools for DSL requires the definition of models semantics. In this paper, we propose a framework to give a formal foundation of the Model-Driven Engineering (MDE) approach. We separate the usually common notions of models and modelling languages associating to each of them a different goal. In order to prove the consistency of our proposal we express a subset of EMOF, its static semantics and validate its meta-circularity

A Proof Assistant Based Formalization of components in MDE

International audienceModel driven engineering (MDE) now plays a key role in the development of safety critical systems through the use of early validation and verification of models, and the automatic generation of software and hardware artifacts from the validated and verified models. In order to ease the integration of formal specification and verification technologies, various formalizations of the MDE technologies were proposed by different authors using term or graph rewriting, proof assistants, logical frameworks, etc. The use of components is also mandatory to improve the efficiency of system development. Invasive Software Composition (ISC) has been proposed by Assman to add a generic component structure to existing Domain Specific Modeling Languages in MDE. This approach is the basis of the ReuseWare toolset. We present in this paper an extension of a formal embedding of some key aspects of MDE in set theory in order to formalize ISC and prove the correctness of the proposed approach with respect to the conformance relation with the base metamodel. The formal embedding we rely on was developed by some of the authors and then implemented using the Calculus of Inductive Construction and the Coq proof-assistant. This work is a first step in the formalization of composable verification technologies in order to ease its integration for DSML extended with component features using ISC

Essay on Semantics Definition in MDE. An Instrumented Approach for Model Verification

International audienceIn the context of MDE (Model-Driven Engineering), our objective is to define the semantics for a given DSL (Domain Specific Language) either to simulate its models or to check properties on them using model-checking techniques. In both cases, the purpose is to formalize the DSL semantics as it is known by the DSL designer but often in an informal way. After several experiments to define operational semantics on the one hand, and translational semantics on the other hand, we discuss both approaches and we specify in which cases these semantics seem to be judicious. As a second step, we introduce a pragmatic and instrumented approach to define a translational semantics and to validate it against a reference operational semantics expressed by the DSL designer. We apply this approach to the xSPEM process description language in order to verify process models

A Property-Driven Approach to Formal Verification of Process Models

Enterprise Information Systems, 9th International Conference, ICEIS 2007, Funchal, Madeira, June 12-16, 2007, Revised Selected PapersInternational audienceMore and more, models, through Domain Specific Languages (DSL), tend to be the solution to define complex systems. Expressing properties specific to these metamodels, and checking them, appear as an urgent need. Until now, the only complete industrial solutions that are available consider structural properties such as the ones that could be expressed in OCL. There are although some attempts on behavioural properties for DSL. This paper addresses a method to specify and then check temporal properties over models. The case study is SimplePDL, a process metamodel. We propose a way to use a temporal extension of OCL, TOCL, to express properties. We specify a models transformation to Petri Nets and LTL formulae for both the process model and its associated temporal properties. We check these properties using a model checker and enrich the model with the analysis results. This work is a first step towards a generic framework to specify and effectively check temporal properties over arbitrary models

La composition de services dans le monde asynchrone Formalisation et vérification en TLA+

International audienceLes architectures orientées services (SOA) permettent de répondre à deux défis importants du génie logiciel : la rutilisabilité et la décomposition. Néanmoins elles amènent de nouveaux problème, notamment liés à la répartition des services et la non-centralisation du contrôle. Les services étant indépendants et autonomes, il faut s’assurer que mis ensemble ils sont capables de communiquer et que leurs interactions n’introduisent pas de mauvais fonctionnement global. Dans le monde asynchrone, plus proche de la réalité, cette vérification devient non triviale, et cela d’autant plus qu’il existe de multiples modèles asynchrones, plus ou moins libéraux dans ce qu’ils autorisent. Nous exposons dans ce papier nos travaux en cours autour des modèles asynchrones et de la vérification des compositions de services paramétrées par ces modèles

Towards a Formal Verification of Process Model's Properties - SimplePDL and TOCL Case Study

International audienceMore and more, models, through Domain Specific Languages (DSL), tend to be the solution to define complex systems. Expressing properties specific to these metamodels and checking them appear as an urgent need. Until now, the only complete industrial solutions that are available consider structural properties such as the ones that could be expressed in OCL. There are although some attempts on behavioural properties for DSL. This paper addresses a method to specify and then check temporal properties over models. The case study is SimplePDL, a process metamodel. We propose a way to use a temporal extension of OCL, TOCL, to express properties. We specify a models transformation to Petri Nets and LTL formulae for both the process model and its associated temporal properties. We check these properties using a model checker and enrich the model with the analysis results. This work is a first step towards a generic framework to specify and effectively check temporal properties over arbitrary models

A constraint programming approach for polytopic simulation of ordinary differential equations - a collision detection application

[no abstract available

A Proof Assistant Based Formalization of components in MDE

International audienceModel driven engineering (MDE) now plays a key role in the development of safety critical systems through the use of early validation and verification of models, and the automatic generation of software and hardware artifacts from the validated and verified models. In order to ease the integration of formal specification and verification technologies, various formalizations of the MDE technologies were proposed by different authors using term or graph rewriting, proof assistants, logical frameworks, etc. The use of components is also mandatory to improve the efficiency of system development. Invasive Software Composition (ISC) has been proposed by Assman to add a generic component structure to existing Domain Specific Modeling Languages in MDE. This approach is the basis of the ReuseWare toolset. We present in this paper an extension of a formal embedding of some key aspects of MDE in set theory in order to formalize ISC and prove the correctness of the proposed approach with respect to the conformance relation with the base metamodel. The formal embedding we rely on was developed by some of the authors and then implemented using the Calculus of Inductive Construction and the Coq proof-assistant. This work is a first step in the formalization of composable verification technologies in order to ease its integration for DSML extended with component features using ISC

Dépliage de Boucles Versus Précision Numérique

Les calculs en nombres flottants sont intensivement utilisés dans divers domaines, notamment les systèmes embarqués critiques. En général, les résultats de ces calculs sont perturbés par les erreurs d’arrondi. Dans un scenario critique, ces erreurs peuvent être accumulées et propagées, générant ainsi des dommages plus ou moins graves sur le plan humain, matériel, financier, etc. Il est donc souhaitable d’obtenir les résultats les plus précis possibles lorsque nous utilisons l’arithmétique flottante. Pour remédier à ce problème, l’outil Salsa [7] permet d’améliorer la précision des calculs en corrigeant partiellement ces erreurs d’arrondi par une transformation automatique et source à source des programmes. La principale contribution de ce travail consiste à analyser, à étudier si l’optimisation par dépliage de boucles améliore plus la précision numérique des calculs dans le programme initial. À cours terme, on souhaite définir un facteur de dépliage de boucles, c’est à dire, trouver quand est-ce qu’il est pertinent de déplier la boucle dans le programme