Tools and Algorithms for the Construction and Analysis of Systems : : 27th International Conference, TACAS 2021, Held As Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2021, Luxembourg City, Luxembourg, March 27 - April 1, 2021, Proceedings, Part II.

• Superior document: Lecture Notes in Computer Science Series ; v.12652
• Author: Groote, Jan Friso.
• TeilnehmendeR: Larsen, Kim Guldstrand.
• Place / Publishing House: Cham : : Springer International Publishing AG,, 2021.; ©2021.
• Year of Publication: 2021
• Edition: 1st ed.
• Language: English
• Series: Lecture Notes in Computer Science Series
• Physical Description: 1 online resource (476 pages)

Table of Contents

Intro -- ETAPS Foreword -- Preface -- Organization -- Contents - Part II -- Contents - Part I -- Verification Techniques (not SMT) -- Directed Reachability for Infinite-State Systems -- 1 Introduction -- 2 Preliminaries -- 3 Directed Search Algorithms -- 4 Directed Reachability -- 4.1 Distance Under-approximations -- 4.2 From Petri Net Relaxations to Distance Under-approximations -- 4.3 Directed Reachability Based on Distance Under-approximations -- 5 Experimental Results -- References -- Bridging Arrays and ADTs in Recursive Proofs -- 1 Introduction -- 2 Preliminaries -- 3 Synthesis of Recursive Relational Invariants -- 3.1 Overview -- 3.2 Classifying Operations -- 4 Recipe 1: Linear Scan -- 4.1 Motivating Example -- 4.2 Algorithm Description -- 5 Recipe 2: Noop-based synthesis -- 5.1 Motivating Example -- 5.2 Algorithm details -- 6 Evaluation -- 7 Related Work -- 8 Conclusion and Outlook -- References -- A Two-Phase Approach forConditional Floating-Point Verification -- 1 Introduction -- 2 A Two-Phase Approach -- 2.1 First Phase: Whole Program Analysis -- 2.2 Second Phase: Numerical Kernel Analysis -- 2.3 Soundness Guarantees -- 3 First Phase: Whole Program Analysis -- 4 Second Phase: Static Analysis with Daisy and CBMC -- 5 State of the Art on Real-World Programs -- 6 Evaluation of our Two-Phase Approach -- 7 Related Work -- 8 Conclusion -- Acknowledgements -- References -- Symbolic Coloured SCC Decomposition -- 1 Introduction -- 1.1 Related Work -- 2 Problem Definition -- 2.1 Graphs and Strongly Connected Components -- 2.2 Coloured SCC Decomposition Problem -- 3 Algorithm -- 3.1 Symbolic Computation Model -- 3.2 Forward-backward Algorithm -- 3.3 Lock-step Algorithm -- 3.4 Coloured Lock-step Algorithm -- 3.5 Correctness and Complexity of the Coloured Lock-step Algorithm -- 4 Experimental Evaluation -- 4.1 Implementation -- 4.2 Experiments.

5 Conclusions -- References -- Case Studies -- Local Search with a SAT Oracle for Combinatorial Optimization -- 1 Introduction -- 2 Background -- 2.1 Constraint Optimization Program (COP) -- 2.2 The Cell Placement Problem -- 2.2.1 Constraint Optimization Program for Cell Placement -- 2.3 Solving COP with SAT -- 2.3.1 Bit-vector Solving and SAT. -- 2.3.2 Extending Bit-vector Solving to Optimization. -- 2.4 Local Search Algorithms -- 2.4.1 Basic Local Search Strategy. -- 2.4.2 Neighbourhood Functions. -- 2.4.3 Advanced Versions of Local Search -- 3 Local Search with SAT Oracle (LSSO) -- 4 LSSO Algorithms for the Cell Placement Problem -- 4.1 Neighbourhood Generators -- 4.1.1 Neighbourhood Generator -- 4.1.2 N₂: a Family of Neighbourhood Generators -- 4.1.3 Hill-climbing Neighbourhood Generator N₃. -- 4.2 LSSO-based Algorithms for Placement -- 5 Experimental Results -- 6 Conclusion -- References -- Analyzing Infrastructure as Code to Prevent Intra-update Sniping Vulnerabilities -- 1 Introduction -- 1.1 Proof of Concept -- 1.2 Detecting Intra-update Sniping Vulnerabilities -- 2 A Model for Infrastructure as Code -- 2.1 CloudFormation Infrastructures -- 2.2 Model of a CloudFormation Infrastructure -- 2.3 Execution Semantics -- 2.4 Upgrade Semantics and Security Policy -- 3 Architectural Design of the Hayha Tool -- 3.1 Upgrade States -- 3.2 Splitting Dependencies -- 3.3 Finding Vulnerabilities -- 4 Experiments -- 5 Related Work -- 6 Conclusion -- Acknowledgement -- References -- Proof Generation/Validation -- Certifying Proofs in the First-Order Theory of Rewriting -- 1 Introduction -- 2 Preliminaries -- 3 Formulas -- 4 Certificates -- 5 FORTify -- 6 FORT-h -- 7 Experiments -- 8 Conclusion -- References -- Syntax-Guided Quantifier Instantiation -- 1 Introduction -- 2 Background -- 3 SyGuS Quantifier Instantiation (SyQI) -- 3.1 Grammar Construction.

3.2 Implementation Details -- 4 Experiments -- 5 Conclusion -- References -- Making Theory Reasoning Simpler -- 1 Introduction -- 2 Preliminaries and Related Work -- 3 Gaussian variable elimination -- 4 Arithmetic subterm generalization -- 5 Evaluation -- 6 Cancellation -- 7 Experimental evaluation -- 8 Conclusion -- References -- Deductive Stability Proofs for Ordinary Differential Equations -- 1 Introduction -- 2 Background: Di erential Dynamic Logic -- 3 Asymptotic Stability of an Equilibrium Point -- 3.1 Mathematical Preliminaries -- 3.2 Formal Specification -- 3.3 Lyapunov Functions -- 3.4 Asymptotic Stability Variations -- 4 General Stability -- 4.1 General Stability and General Attractivity -- 4.2 Specialization -- 5 Stability in KeYmaera X -- 6 Related Work -- 7 Conclusion -- References -- Tool Papers -- An SMT-Based Approach for Verifying Binarized Neural Networks -- 1 Introduction -- 2 Background -- 3 Extending Reluplex to Support Sign Constraints -- 4 Optimizations -- 5 Implementation -- 6 Evaluation -- 7 Related Work -- 8 Conclusion -- Acknowledgements. -- References -- cake_lpr: Verified Propagation Redundancy Checking in CakeML -- 1 Introduction -- 2 Background -- 2.1 HOL4 and CakeML -- 2.2 SAT Problems and Clausal Proofs -- 3 Linear Propagation Redundancy -- 4 CakeML Proof Checking -- 4.1 Verification Strategy -- 4.2 Verified Optimizations -- 5 Benchmarks -- 5.1 SaDiCaL PR Benchmarks -- 5.2 SAT Race 2019 Benchmarks -- 5.3 Mutilated Chessboard RAT Microbenchmarks -- 6 Related Work -- 7 Conclusion -- Acknowledgments. -- A Correctness Theorem for cake_lpr -- References -- Deductive Verification of Floating-Point Java Programs in KeY -- 1 Introduction -- 2 Background -- 2.1 Introduction to KeY -- 2.2 Floating-Point Arithmetic in Java -- 3 Floating-Point Support in KeY -- 3.1 Arithmetics -- 3.2 Transcendental Functions -- 4 Evaluation.

4.1 Benchmark Programs -- 4.2 Proof Obligation Generation -- 4.3 Evaluation of SMT Floating-Point Support -- 4.4 Evaluation of Support for Transcendental Functions in KeY -- 4.5 Discussion and insights -- 5 Related Work -- 6 Conclusion -- Acknowledgements -- References -- Helmholtz: A Verifier for Tezos Smart Contracts Based on Refinement Types -- 1 Introduction -- 2 Overview of Helmholtz and Michelson -- 2.1 Helmholtz -- 2.2 An Example Contract in Michelson -- 2.3 Specification -- 3 Refinement Type System for Mini-Michelson -- 3.1 Operational Semantics -- 3.2 Refinement Type System -- 4 Tool Implementation -- 4.1 Annotations -- 4.2 Case Study: Contract with Signature Verification -- 4.3 Experiments -- 5 Related Work -- 6 Conclusion -- References -- SyReNN: A Tool for Analyzing Deep Neural Networks -- 1 Introduction -- 2 Preliminaries -- 3 A Symbolic Representation of DNNs -- 4 Computing the Symbolic Representation -- 4.1 Algorithm for Extend -- 4.2 Representing Polytopes -- 5 SyReNN tool -- 6 Applications of SyReNN -- 6.1 Integrated Gradients -- 6.2 Visualization of DNN Decision Boundaries -- 6.3 Patching of DNNs -- 7 Related Work -- 8 Conclusion and Future Work -- References -- MachSMT: A Machine Learning-based Algorithm Selector for SMT Solvers -- 1 Introduction -- 2 Background -- 2.1 A Brief Overview of Algorithm Selection -- 2.2 Supervised Learning, Adaptive Boosting, Curse of Dimensionality, and K-Fold Cross-Validation -- 2.3 Unsupervised Learning and Principal Component Analysis -- 3 An overview of MachSMT -- 3.1 Features, Preprocessing, and Learning -- 3.2 Variants of MachSMT -- 3.3 Using MachSMT -- 3.4 User-defined Features -- 4 Experimental Evaluation of MachSMT on SMT-COMP 2019 and 2020 Data -- 4.1 Experimental Setup and Methodology -- 4.2 Experimental Results -- 5 Analysis and Discussion of Results -- 6 Related Work.

6.1 Key di erences between SATZilla and MachSMT -- 6.2 Algorithm Selection for Logic Solvers and Their Applications -- 7 Conclusions and Future Work -- References -- dtControl 2.0: Explainable Strategy Representation via Decision Tree Learning Steered by Experts -- 1 Introduction -- 2 Decision tree learning for controller representation -- 3 Tool -- 4 Predicate domain -- 4.1 Categorical predicates -- 4.2 Algebraic predicates -- 5 Predicate selection -- 6 New insights about determinization -- 7 Experiments -- 8 Conclusion -- References -- Tool Demo Papers -- HLola: a Very Functional Tool for Extensible Stream Runtime Verification -- 1 Introduction -- 2 The HLola Tool -- 3 Example Specifications -- References -- AMulet 2.0 for Verifying Multiplier Circuits -- 1 Introduction -- 2 Circuit Verification using Computer Algebra -- 3 Usage -- 4 AMulet 2.0 -- 5 Evaluation -- 6 Conclusion -- References -- RTLola on Board: Testing Real Driving Emissions on your Phone -- 1 Introduction -- 2 RDE Monitoring on Android -- 3 User Experience -- 4 Conclusion -- References -- Replicating Restart with ProlongedRetrials: An Experimental Report -- 1 Introduction -- 2 Restart with Prolonged Retrials -- 3 Experiments -- 4 Conclusion -- References -- A Web Interface for Petri Nets with Transits and Petri Games -- 1 Introduction -- 2 Web Interface for Petri Nets with Transits -- 3 Web Interface for Petri Games -- 4 Implementation Details -- 5 Conclusion -- References -- Momba: JANI Meets Python -- 1 Introduction -- 2 Scenario-Based Model Construction -- 3 Validation by Simulation -- 4 Harvesting the Benefits -- 5 Conclusion -- References -- SV-Comp Tool Competition Papers -- Software Verification: 10th Comparative Evaluation (SV-COMP 2021) -- 1 Introduction -- 2 Organization, Definitions, Formats, and Rules -- 3 Reproducibility -- 4 Results and Discussion -- 5 Conclusion.

References.