Graph Based Reduction of Program Verification Conditions

Increasing the automaticity of proofs in deductive verification of C programs is a challenging task. When applied to industrial C programs known heuristics to generate simpler verification conditions are not efficient enough. This is mainly due to their size and a high number of irrelevant hypotheses. This work presents a strategy to reduce program verification conditions by selecting their relevant hypotheses. The relevance of a hypothesis is determined by the combination of a syntactic analysis and two graph traversals. The first graph is labeled by constants and the second one by the predicates in the axioms. The approach is applied on a benchmark arising in industrial program verification

Opportunities for a Truffle-based Golo Interpreter

Golo is a simple dynamically-typed language for the Java Virtual Machine. Initially implemented as a ahead-of-time compiler to JVM bytecode, it leverages invokedy-namic and JSR 292 method handles to implement a reasonably efficient runtime. Truffle is emerging as a framework for building interpreters for JVM languages with self-specializing AST nodes. Combined with the Graal compiler, Truffle offers a simple path towards writing efficient interpreters while keeping the engineering efforts balanced. The Golo project is interested in experimenting with a Truffle interpreter in the future, as it would provides interesting comparison elements between invokedynamic versus Truffle for building a language runtime

Syntactic Abstraction of B Models to Generate Tests

In a model-based testing approach as well as for the verification of properties, B models provide an interesting solution. However, for industrial applications, the size of their state space often makes them hard to handle. To reduce the amount of states, an abstraction function can be used, often combining state variable elimination and domain abstractions of the remaining variables. This paper complements previous results, based on domain abstraction for test generation, by adding a preliminary syntactic abstraction phase, based on variable elimination. We define a syntactic transformation that suppresses some variables from a B event model, in addition to a method that chooses relevant variables according to a test purpose. We propose two methods to compute an abstraction A of an initial model M. The first one computes A as a simulation of M, and the second one computes A as a bisimulation of M. The abstraction process produces a finite state system. We apply this abstraction computation to a Model Based Testing process.Comment: Tests and Proofs 2010, Malaga : Spain (2010

Towards a Decoupled Context-Oriented Programming Language for the Internet of Things

Easily programming behaviors is one major issue of a large and reconfigurable deployment in the Internet of Things. Such kind of devices often requires to externalize part of their behavior such as the sensing, the data aggregation or the code offloading. Most existing context-oriented programming languages integrate in the same class or close layers the whole behavior. We propose to abstract and separate the context tracking from the decision process, and to use event-based handlers to interconnect them. We keep a very easy declarative and non-layered programming model. We illustrate by defining an extension to Golo-a JVM-based dynamic language

Vérification de propriétés LTL sur des programmes C par génération d'annotations

Ce travail propose une méthode de vérification de propriétés temporelles basée sur la génération automatique d'annotations de programmes. Les annotations générées sont ensuite vérifiées par des prouveurs automatiques via un calcul de plus faible précondition. Notre contribution vise à optimiser une technique existante de génération d'annotations, afin d'améliorer l'automatisation de la vérification des obligations de preuve produites. Cette approche a été outillée sous la forme d'un plugin au sein de l'outil Frama-C pour la vérification de programmes~

OSGiLarva : a monitoring framework supporting OSGi’s dynamicity

Service-Oriented Architecture is an approach where software systems are designed in terms of a composition of services. OSGi is a Service-Oriented Framework dedicated to 24/7 Java systems. In this Service-Oriented Programming approach, software is composed of services that may dynamically appear or disappear. In such a case, classical monitoring approaches with statically injected monitors into services cannot be used. In this paper, we describe ongoing work proposing a dynamic monitoring approach dedicated to local SOA systems, focusing particularly on OSGi. Firstly, we define two key properties of loosely coupled monitoring systems: dynamicity resilience and comprehensiveness. Next, we propose the OSGiLarva tool, which is a preliminary implementation targeted at the OSGi framework. Finally, we present some quantitative results showing that a dynamic monitor based on dynamic proxies and another based on aspect-oriented programming have equivalent performances.peer-reviewe

Le Libre : catalyseur de l'Humanisme ?

National audienceL'ingénieur humaniste doit comprendre le monde et œuvrer à la diffusion large et sans barrières ni discrimination de la connaissance. Ce concept résonne largement avec celui de la culture libre, qui promeut la liberté de distribution des biens non matériels tels que logiciels, inventions, connaissances, etc.. Nous défendons donc dans cette communication que la sensibilisation à la culture libre est à la fois une opportunité et une nécessité pour la formation d'ingénieurs humanistes. Nous proposons également quelques pistes de réflexion pour l'intégration de cette culture libre dans notre contexte

B Model Slicing and Predicate Abstraction to Generate Tests

Accepted manuscript. Revised and extended version of a TAP'10 paper. To appear.International audienceIn a model-based testing approach as well as for the verification of properties, B models provide an interesting modeling solution. However, for industrial applications, the size of their state space often makes them hard to handle. To reduce the amount of states, an abstraction function can be used. The abstraction is often a domain abstraction of the state variables that requires many proof obligations to be discharged, which can be very time-consuming for real applications. This paper presents a contribution to this problem that complements an approach based on domain abstraction for test generation, by adding a preliminary syntactic abstraction phase, based on variable elimination. We define a syntactic transformation that suppresses some variables from a B event model, in addition to three methods that choose relevant variables according to a test purpose. In this way, we propose a method that computes an abstraction of a source model {\mathsf{M}} according to a set of selected relevant variables. Depending on the method used, the abstraction can be computed as a simulation or as a bisimulation of {\mathsf{M}}. With this approach, the abstraction process produces a finite state system. We apply this abstraction computation to a model-based testing process. We evaluate experimentally the impact of the model simplification by variables' elimination on the size of the models, on the number of proof obligations to discharge, on the precision of the abstraction and on the coverage achieved by the test generation