Abstract Analysis of Universal Properties for tccp

[EN] The Timed Concurrent Constraint Language (tccp) is a time extension of the concurrent constraint paradigm of Saraswat. tccp was defined to model reactive systems, where infinite behaviors arise naturally. In previous works, a semantic framework and abstract diagnosis method for the language has been defined. On the basis of that semantic framework, this paper proposes an abstract semantics that, together with a widening operator, is suitable for the definition of different analyses for tccp programs. The abstract semantics is correct and can be represented as a finite graph where each node represents a hypothetical computational step of the program containing approximated information for the variables. The widening operator allows us to guarantee the convergence of the abstract fixpoint computation.This work has been supported by the Andalusian Excellence Project P11-TIC7659. This work has been partially supported by the EU (FEDER) and the Spanish MINECO under grant TIN 2013-45732-C4-1-P (DAMAS) and by Generalitat Valenciana PROMETEOII/2015/013Comini, M.; Gallardo Melgarejo, MDM.; Titolo, L.; Villanueva, A. (2015). Abstract Analysis of Universal Properties for tccp. Lecture Notes in Computer Science. 163-178. https://doi.org/10.1007/978-3-319-27436-2_10S163178Alpuente, M., Gallardo, M.M., Pimentel, E., Villanueva, A.: A semantic framework for the abstract model checking of tccp programs. Theor. Comput. Sci. 346(1), 58–95 (2005)Bagnara, R., Hill, P.M., Ricci, E., Zaffanella, E.: Precise widening operators for convex polyhedra. Sci Comput. Program. 58(1–2), 28–56 (2005)Comini, M., Titolo, L., Villanueva, A.: Abstract diagnosis for timed concurrent constraint programs. Theor. Pract. Log. Program. 11(4–5), 487–502 (2011)Comini, M., Titolo, L., Villanueva, A.: A condensed goal-independent bottom-up fixpoint modeling the behavior of tccp. Technical report, DSIC, Universitat Politècnica de València (2013). http://riunet.upv.es/handle/10251/34328Cousot, P., Cousot, R.: Abstract Interpretation: a unified lattice model for static analysis of programs by construction or approximation of fixpoints. In: Proceedings of the 4th ACM SIGACT-SIGPLAN Symposium on Principles of Programming Languages, Los Angeles, California, January 17–19, pp. 238–252. ACM Press, New York (1977)de Boer, F.S., Gabbrielli, M., Meo, M.C.: A timed concurrent constraint language. Inf. Comput. 161(1), 45–83 (2000)Falaschi, M. Gabbrielli, M., Marriott, K., Palamidessi, C.: Compositional analysis for concurrent constraint programming. In: Proceedings of the Eighth Annual IEEE Symposium on Logic in Computer Science, pp. 210–221. IEEE Computer Society Press, Los Alamitos (1993)Falaschi, M., Olarte, C., Palamidessi, C.: Abstract interpretation of temporal concurrent constraint programs. Theor. Pract. Log. Program. (TPLP) 15(3), 312–357 (2015)Falaschi, M., Villanueva, A.: Automatic verification of timed concurrent constraint programs. Theor. Pract. Log. Program. 6(3), 265–300 (2006)Saraswat, V.A.: Concurrent Constraint Programming. The MIT Press, Cambridge (1993)Zaffanella, E., Giacobazzi, R., Levi, G.: Abstracting synchronization in concurrent constraint programming. J. Funct. Log. Program. 6, 1997 (1997

A program analysis framework for tccp based on abstract interpretation

[EN] The timed concurrent constraint language (tccp) is a timed extension of the concurrent constraint paradigm. tccp was defined to model reactive systems, where infinite behaviors arise naturally. In previous works, a semantic framework and abstract diagnosis method for the language have been defined. On the basis of that semantic framework, this paper proposes an abstract semantics that, together with a widening operator, is suitable for the definition of different analyses for tccp programs. The abstract semantics is correct and can be represented as a finite graph where each node represents a hypothetical (abstract) computational step of the program. The widening operator allows us to guarantee the convergence of the abstract fixpoint computation.This author has been supported by the Andalusian Excellence Project P11-TIC-7659. This work has been partially supported by the EU (FEDER) and the Spanish MINECO under grants TIN 2015-69175-C4-1-R and TIN 2013-45732-C4-1-P and by Generalitat Valenciana PROMETEOII/2015/013Comini, M.; Gallardo, M.; Titolo, L.; Villanueva, A. (2017). A program analysis framework for tccp based on abstract interpretation. Formal Aspects of Computing. 29(3):531-557. https://doi.org/10.1007/s00165-016-0409-8S531557293Alpuente M, Gallardo MM, Pimentel E, Villanueva A (2006) A semantic framework for the abstract model checking of tccp programs. Theor Comput Scie 346(1): 58–95Bagnara R, Hill PM., Ricci E, Zaffanella E (2005) Precise widening operators for convex polyhedra. Sci Comput Program 58(1–2):28–56Cousot P, Cousot R (1977) Abstract interpretation: a unified lattice model for static analysis of programs by construction or approximation of fixpoints. In: Proceedings of the 4th ACM SIGACT-SIGPLAN symposium on principles of programming languages, Los Angeles, California, January 17–19. ACM Press, New York, pp 238–252Clarke EM, Grumberg O, Jha S, Lu Y, Veith H (2000) Counterexample-guided abstraction refinement. In: CAV, Lecture Notes in Computer Science, vol 1855. Springer, pp 154–169Comini M, Gallardo MM, Titolo L, Villanueva A (2015) Abstract Analysis of Universal Properties for tccp. In: Falaschi M (ed) Logic-based Program Synthesis and Transformation, 25th International Symposium, LOPSTR 2015. Revised Selected Papers, Lecture Notes in Computer Science, vol 9527. Springer, pp 163–178Comini M, Titolo L, Villanueva A (2011) Abstract diagnosis for timed concurrent constraint programs. Theory Pract Logic Programm 11(4-5):487–502Comini M, Titolo L, Villanueva A (2013) A condensed goal-independent bottom-up fixpoint modeling the behavior of tccp. Technical report, DSIC, Universitat Politècnica de València. http://riunet.upv.es/handle/10251/34328de Boer FS, Gabbrielli M, Meo MC (2000) A timed concurrent constraint language. Inf Comput 161(1): 45–83Falaschi M, Gabbrielli M, Marriott K, Palamidessi C (1993) Compositional analysis for concurrent constraint programming. In: Proceedings of the eighth annual IEEE symposium on logic in computer science, Los Alamitos, CA, USA, IEEE Computer Society Press, pp 210–221Falaschi M, Olarte C, Palamidessi C (2015) Abstract interpretation of temporal concurrent constraint programs. Theory and Pract Logic Program (TPLP) 15(3): 312–357Falaschi M, Villanueva A (2006) Automatic verification of timed concurrent constraint programs. Theory Pract Logic Program 6(3): 265–300Gallardo MM, Merino P, Pimentel E (2002) Refinement of LTL formulas for abstract model checking. In: Static analysis, 9th international symposium, SAS 2002, Madrid, Spain, September 17–20, 2002, Proceedings, pp 395–410Saraswat VA (1993) Concurrent constraint programming. The MIT Press, CambridgeSaraswat VA, Rinard M, Panangaden P (1991) The semantic foundations of concurrent constraint programming. In: Proceedings of the 18th ACM SIGPLAN-SIGACT symposium on principles of programming languages. ACM, New York, pp 333–352Zaffanella E, Giacobazzi R, Levi G (1997) Abstracting synchronization in concurrent constraint programming. J Funct Logic Program (6

Towards an Effective Decision Procedure for LTL formulas with Constraints

This paper presents an ongoing work that is part of a more wide-ranging project whose final scope is to define a method to validate LTL formulas w.r.t. a program written in the timed concurrent constraint language tccp, which is a logic concurrent constraint language based on the concurrent constraint paradigm of Saraswat. Some inherent notions to tccp processes are non-determinism, dealing with partial information in states and the monotonic evolution of the information. In order to check an LTL property for a process, our approach is based on the abstract diagnosis technique. The concluding step of this technique needs to check the validity of an LTL formula (with constraints) in an effective way. In this paper, we present a decision method for the validity of temporal logic formulas (with constraints) built by our abstract diagnosis technique.Comment: Part of WLPE 2013 proceedings (arXiv:1308.2055

Quantitative Analysis of Probabilistic Models of Software Product Lines with Statistical Model Checking

We investigate the suitability of statistical model checking techniques for analysing quantitative properties of software product line models with probabilistic aspects. For this purpose, we enrich the feature-oriented language FLan with action rates, which specify the likelihood of exhibiting particular behaviour or of installing features at a specific moment or in a specific order. The enriched language (called PFLan) allows us to specify models of software product lines with probabilistic configurations and behaviour, e.g. by considering a PFLan semantics based on discrete-time Markov chains. The Maude implementation of PFLan is combined with the distributed statistical model checker MultiVeStA to perform quantitative analyses of a simple product line case study. The presented analyses include the likelihood of certain behaviour of interest (e.g. product malfunctioning) and the expected average cost of products.Comment: In Proceedings FMSPLE 2015, arXiv:1504.0301

Service discovery and negotiation with COWS

To provide formal foundations to current (web) services technologies, we put forward using COWS, a process calculus for specifying, combining and analysing services, as a uniform formalism for modelling all the relevant phases of the life cycle of service-oriented applications, such as publication, discovery, negotiation, deployment and execution. In this paper, we show that constraints and operations on them can be smoothly incorporated in COWS, and propose a disciplined way to model multisets of constraints and to manipulate them through appropriate interaction protocols. Therefore, we demonstrate that also QoS requirement specifications and SLA achievements, and the phases of dynamic service discovery and negotiation can be comfortably modelled in COWS. We illustrate our approach through a scenario for a service-based web hosting provider

A Calculus for Orchestration of Web Services

Service-oriented computing, an emerging paradigm for distributed computing based on the use of services, is calling for the development of tools and techniques to build safe and trustworthy systems, and to analyse their behaviour. Therefore, many researchers have proposed to use process calculi, a cornerstone of current foundational research on specification and analysis of concurrent, reactive, and distributed systems. In this paper, we follow this approach and introduce CWS, a process calculus expressly designed for specifying and combining service-oriented applications, while modelling their dynamic behaviour. We show that CWS can model all the phases of the life cycle of service-oriented applications, such as publication, discovery, negotiation, orchestration, deployment, reconfiguration and execution. We illustrate the specification style that CWS supports by means of a large case study from the automotive domain and a number of more specific examples drawn from it

Bounded LTL Model Checking with Stable Models

In this paper bounded model checking of asynchronous concurrent systems is introduced as a promising application area for answer set programming. As the model of asynchronous systems a generalisation of communicating automata, 1-safe Petri nets, are used. It is shown how a 1-safe Petri net and a requirement on the behaviour of the net can be translated into a logic program such that the bounded model checking problem for the net can be solved by computing stable models of the corresponding program. The use of the stable model semantics leads to compact encodings of bounded reachability and deadlock detection tasks as well as the more general problem of bounded model checking of linear temporal logic. Correctness proofs of the devised translations are given, and some experimental results using the translation and the Smodels system are presented.Comment: 32 pages, to appear in Theory and Practice of Logic Programmin