7,482 papers · page 184 of 375
When constructing complex concurrent systems, abstraction is vital: programmers should be able to reason about concurrent libraries in terms of abstract specifications that hide the implementation details. Relaxed memory models present substantial challenges in this respect, as l…
In this paper we study the complexity of the Linear Ranking problem: given a loop, described by linear constraints over a finite set of integer variables, is there a linear ranking function for this loop? While existence of such a function implies termination, this problem is not…
We present a calculus for processing semistructured data that spans differences of application area among several novel query languages, broadly categorized as "NoSQL". This calculus lets users define their own operators, capturing a wider range of data processing capabilities, w…
The widely studied I/O and ideal-cache models were developed to account for the large difference in costs to access memory at different levels of the memory hierarchy. Both models are based on a two level memory hierarchy with a fixed size primary memory(cache) of size M, an unbo…
We introduce bisimulation up to congruence as a technique for proving language equivalence of non-deterministic finite automata. Exploiting this technique, we devise an optimisation of the classical algorithm by Hopcroft and Karp. We compare our approach to the recently introduce…
We present Sigma*, a novel technique for learning symbolic models of software behavior. Sigma* addresses the challenge of synthesizing models of software by using symbolic conjectures and abstraction. By combining dynamic symbolic execution to discover symbolic input-output steps…
We introduce the concept of behavioral separation as a general principle for disciplining interference in higher-order imperative concurrent programs, and present a type-based approach that systematically develops the concept in the context of an ML-like language extended with co…
Over the last decade, global descriptions have been successfully employed for the verification and implementation of communicating systems, respectively as protocol specifications and choreographies. In this work, we bring these two practices together by proposing a purely-global…
We propose a general framework for abstraction with respect to quantitative properties, such as worst-case execution time, or power consumption. Our framework provides a systematic way for counter-example guided abstraction refinement for quantitative properties. The salient aspe…
Modern satisfiability solvers implement an algorithm, called Conflict Driven Clause Learning, which combines search for a model with analysis of conflicts. We show that this algorithm can be generalised to solve the lattice-theoretic problem of determining if an additive transfor…
Formalizing meta-theory, or proofs about programming languages, in a proof assistant has many well-known benefits. Unfortunately, the considerable effort involved in mechanizing proofs has prevented it from becoming standard practice. This cost can be amortized by reusing as much…
Recent advances in verification have made it possible to envision trusted implementations of real-world languages. Java with its type-safety and fully specified semantics would appear to be an ideal candidate; yet, the complexity of the translation steps used in production virtua…
Compositional abstractions underly many reasoning principles for concurrent programs: the concurrent environment is abstracted in order to reason about a thread in isolation; and these abstractions are composed to reason about a program consisting of many threads. For instance, s…
The correctness of a sequential program can be shown by the annotation of its control flow graph with inductive assertions. We propose inductive data flow graphs, data flow graphs with incorporated inductive assertions, as the basis of an approach to verifying concurrent programs…
Many tools allow programmers to develop applications in high-level languages and deploy them in web browsers via compilation to JavaScript. While practical and widely used, these compilers are ad hoc: no guarantee is provided on their correctness for whole programs, nor their sec…
Differential privacy offers a way to answer queries about sensitive information while providing strong, provable privacy guarantees, ensuring that the presence or absence of a single individual in the database has a negligible statistical effect on the query's result. Proving tha…
Even with the assistance of computer tools, the formalized de-scription and verification of research-level mathematics remains a daunting task, not least because of the talent with which mathema-ticians combine diverse theories to achieve their ends. By combin-ing tools and techn…
models, probabilistic programs Probabilities describe degrees of belief, and probabilistic inference describes rational reasoning under uncertainty. It is no wonder, then, that probabilistic models have exploded onto the scene of modern artificial intelligence, cognitive science,…
A Bayesian model is based on a pair of probability distributions, known as the prior and sampling distributions. A wide range of fundamental machine learning tasks, including regression, classification, clustering, and many others, can all be seen as Bayesian models. We propose a…
We present a calculus which combines a simple, CCS-like representation of finite behaviors, with two dual binders λ and λ¯. Infinite behaviors are obtained through a syntactical fixed-point operator, which is used to give a translation of λ-terms. The duality of the calculus make…