Constraint solving for finite model finding in SMT solvers*. Issue 4 (28th June 2017)

• Record Type: Journal Article
• Authors: REYNOLDS, ANDREW; TINELLI, CESARE; BARRETT, CLARK
• Is Part Of: Theory and practice of logic programming. Volume 17:Issue 4(2017)
• Page Start: 516
• Page End: 558
• Publication Date: 2017-06-28
• Subjects: Satisfiability modulo theories, -- finite model finding; Logic programming -- Periodicals; Artificial intelligence -- Computer programs -- Periodicals; Constraint programming (Computer science) -- Periodicals; 005.115
• DOI: 10.1017/S1471068417000175
• Languages: English
• ISSNs: 1471-0684

Abstract

Abstract: Satisfiability modulo theories (SMT) solvers have been used successfully as reasoning engines for automated verification and other applications based on automated reasoning. Current techniques for dealing with quantified formulas in SMT are generally incomplete, forcing SMT solvers to report "unknown" when they fail to prove the unsatisfiability of a formula with quantifiers. This inability to return counter models limits their usefulness in applications that produce queries involving quantified formulas. In this paper, we reduce these limitations by integrating finite model finding techniques based on constraint solving into the architecture used by modern SMT solvers. This approach is made possible by a novel solver for cardinality constraints, as well as techniques for on-demand instantiation of quantified formulas. Experiments show that our approach is competitive with the state of the art in SMT, and orthogonal to approaches in automated theorem proving.