1. Disjoint Projected Enumeration for SAT and SMT without Blocking Clauses
- Author
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Spallitta, Giuseppe, Sebastiani, Roberto, and Biere, Armin
- Subjects
Computer Science - Logic in Computer Science - Abstract
All-Solution Satisfiability (AllSAT) and its extension, All-Satisfiability Modulo Theories (AllSMT), have become more relevant in recent years, mainly in formal verification and artificial intelligence applications. The goal of these problems is the enumeration of all satisfying assignments to a formula (for SAT and SMT problems, respectively), making them useful for test generation, model checking, and probabilistic inference. Nevertheless, traditional AllSAT algorithms face significant computational challenges due to the exponential growth of the search space and inefficiencies caused by blocking clauses, which cause memory blowups and degrade unit propagation performances in the long term. This paper presents two novel solvers: \solverPlus{}, a projected AllSAT solver, and \solverSMT{}, a projected AllSMT solver. Both solvers combine Conflict-Driven Clause Learning (CDCL) with chronological backtracking to improve efficiency while ensuring disjoint enumeration. To retrieve compact partial assignments we propose a novel aggressive implicant shrinking algorithm to minimize the number of partial assignments, reducing overall search complexity, and compatible with chronological backtracking. Furthermore, we extend the solver framework to handle projected enumeration and SMT formulae effectively and efficiently, adapting the baseline framework to integrate theory reasoning and the distinction between important and non-important variables. An extensive experimental evaluation demonstrates the superiority of our approach compared to state-of-the-art solvers, particularly in scenarios requiring projection and SMT-based reasoning., Comment: arXiv admin note: text overlap with arXiv:2306.00461
- Published
- 2024