Simulating accepting networks of evolutionary processors with filtered connections by accepting evolutionary P systems

In this work, we propose a variant of P system based on the rewriting of string-objects by means of evolutionary rules. The membrane structure of such a P system seems to be a very natural tool for simulating the filters in accepting networks of evolutionary processors with filtered connections. We discuss an informal construction supporting this simulation. A detailed proof is to be considered in an extended version of this work

Counting constraints in flat array fragments

We identify a fragment of Presburger arithmetic enriched with free function symbols and cardinality constraints for interpreted sets, which is amenable to automated analysis. We establish decidability and complexity results for such a fragment and we implement our algorithms. The experiments run in discharging proof obligations coming from invariant checking and bounded model-checking benchmarks show the practical feasibility of our decision procedure

Derivation of Heard-Of Predicates From Elementary Behavioral Patterns

International audienceThere are many models of distributed computing, and no unifying mathematical framework for considering them all. One way to sidestep this issue is to start with simple communication and fault models, and use them as building blocks to derive the complex models studied in the field. We thus define operations like union, succession or repetition, which makes it easier to build complex models from simple ones while retaining expressivity. To formalize this approach, we abstract away the complex models and operations in the Heard-Of model. This model relies on (possibly asynchronous) rounds; sequence of digraphs, one for each round, capture which messages sent at a given round are received before the receiver goes to the next round. A set of sequences, called a heard-of predicate, defines the legal communication behaviors – that is to say, a model of communication. Because the proposed operations behave well with this transformation of operational models into heard-of predicates, we can derive bounds, characterizations, and implementations of the heard-of predicates for the constructions

An Abstract Domain Combinator for Separately Conjoining Memory Abstractions

International audienceThe breadth and depth of heap properties that can be inferred by theunion of today’s shape analyses is quite astounding. Yet, achieving scalabilitywhile supporting a wide range of complex data structures in a generic way remainsa long-standing challenge. In this paper, we propose a way to side-stepthis issue by defining a generic abstract domain combinator for combining memoryabstractions on disjoint regions. In essence, our abstract domain constructionis to the separating conjunction in separation logic as the reduced product constructionis to classical, non-separating conjunction. This approach eases the designof the analysis as memory abstract domains can be re-used by applying ourseparating conjunction domain combinator. And more importantly, this combinatorenables an analysis designer to easily create a combined domain that appliescomputationally-expensive abstract domains only where it is required

Poling: SMT Aided Linearizability Proofs

ns iste nt * Complete * W ell D ocumented*Easyt