Relational Reasoning - Constraint Solving, Deduction, and Program Verification

This dissertation exploits the formal methods paradigm in which the software system and its specification are transformed to a logical formula, such that the formula is valid iff the specification is correct. The thesis provides a reasoning framework for the verification of software systems against relational specifications written in a first-order relational logic. The system description can be given either at the abstract relational level or at the detailed implementation level

Advancing Deductive Program-Level Verification for Real-World Application: Lessons Learned from an Industrial Case Study

This thesis is concerned with practicability of deductive program verification on source code level. As part of a case study for the verification of real-world software, the specification and verification approach to show correctness of the virtualizing kernel PikeOS is presented. Issues within the verification process using current tools and methodologies are discussed and several aspects of these problems are then addressed in detail to improve the verification process and tool usability

Semantic-Directed Clumping of Disjunctive Abstract States *

International audienceTo infer complex structural invariants, shape analyses rely on expressive families of logical properties. Many such analyses manipulate abstract memory states that consist of separating conjunctions of basic predicates describing atomic blocks or summaries. Moreover, they use finite disjunctions of abstract memory states in order to account for dissimilar shapes. Disjunctions should be kept small for scalability, though precision often requires keeping additional case splits. In this context, deciding when and how to merge case splits and to replace them with summaries is critical both for precision and efficiency. Existing techniques use sets of syntactic rules, which are tedious to design and prone to failure. In this paper, we design a semantic criterion to clump abstract states based on their silhouette, which applies not only to the conservative union of disjuncts but also to the weakening of separating conjunctions of memory predicates into inductive summaries. Our approach allows us to define union and widening operators that aim at preserving the case splits that are required for the analysis to succeed. We implement this approach in the MemCAD analyzer and evaluate it on real-world C codes from existing libraries dealing with doubly-linked lists, red-black trees, AVL-trees and splay-trees

Fundamental Approaches to Software Engineering

This open access book constitutes the proceedings of the 24th International Conference on Fundamental Approaches to Software Engineering, FASE 2021, which took place during March 27–April 1, 2021, and was held as part of the Joint Conferences on Theory and Practice of Software, ETAPS 2021. The conference was planned to take place in Luxembourg but changed to an online format due to the COVID-19 pandemic. The 16 full papers presented in this volume were carefully reviewed and selected from 52 submissions. The book also contains 4 Test-Comp contributions

Symbolic Resource Bound Inference

We present an approach for inferring symbolic resource bounds for purely functional programs consisting of recursive functions, algebraic data types and nonlinear arithmetic operations. In our approach, the developer specifies the desired shape of the bound as a program expression containing numerical holes which we refer to as templates. For e.g, time ≤ a ∗ height(tree) + b where a, b are unknowns, is a template that specifies a bound on the execution time. We present a scalable algorithm for computing tight bounds for sequential and parallel execution times by solving for the unknowns in the template. We empirically evaluate our approach on several benchmarks that manipulate complex data structures such as binomial heap, lefitist heap, red-black tree and AVL tree. Our implementation is able to infer hard, nonlinear symbolic time bounds for our benchmarks that are beyond the capability of the existing approaches

Toward Interprocedural Pointer and Effect Analysis for Scala

Static program analysis techniques working on object-oriented languages require precise knowledge of the aliasing relation between variables. This knowledge is important to, among other things, understand the read and write effects of method calls on objects. Understanding such effects in turn enables compiler optimizations and other code transformations such as automated parallelization. This thesis presents a combination of a pointer analysis with a memory effect analysis for the Scala programming language. Our analysis is based on abstract interpretation, and computes summaries of method effects as graphs. This representation allows the analysis to be compositional. Our second contribution is an implementation of our analysis in a tool called Insane. Our tool is built as a plugin for the official Scala compiler. It accepts any Scala program, and is freely available

Proceedings of the 22nd Conference on Formal Methods in Computer-Aided Design – FMCAD 2022

The Conference on Formal Methods in Computer-Aided Design (FMCAD) is an annual conference on the theory and applications of formal methods in hardware and system verification. FMCAD provides a leading forum to researchers in academia and industry for presenting and discussing groundbreaking methods, technologies, theoretical results, and tools for reasoning formally about computing systems. FMCAD covers formal aspects of computer-aided system design including verification, specification, synthesis, and testing

Programming Languages and Systems

This open access book constitutes the proceedings of the 29th European Symposium on Programming, ESOP 2020, which was planned to take place in Dublin, Ireland, in April 2020, as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2020. The actual ETAPS 2020 meeting was postponed due to the Corona pandemic. The papers deal with fundamental issues in the specification, design, analysis, and implementation of programming languages and systems

Tools and Algorithms for the Construction and Analysis of Systems

This book is Open Access under a CC BY licence. The LNCS 11427 and 11428 proceedings set constitutes the proceedings of the 25th International Conference on Tools and Algorithms for the Construction and Analysis of Systems, TACAS 2019, which took place in Prague, Czech Republic, in April 2019, held as part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2019. The total of 42 full and 8 short tool demo papers presented in these volumes was carefully reviewed and selected from 164 submissions. The papers are organized in topical sections as follows: Part I: SAT and SMT, SAT solving and theorem proving; verification and analysis; model checking; tool demo; and machine learning. Part II: concurrent and distributed systems; monitoring and runtime verification; hybrid and stochastic systems; synthesis; symbolic verification; and safety and fault-tolerant systems