GRASP—a new search algorithm for satisfiability
Proceedings of the 1996 IEEE/ACM international conference on Computer-aided design
GRASP: A Search Algorithm for Propositional Satisfiability
IEEE Transactions on Computers
A Computing Procedure for Quantification Theory
Journal of the ACM (JACM)
A machine program for theorem-proving
Communications of the ACM
Chaff: engineering an efficient SAT solver
Proceedings of the 38th annual Design Automation Conference
Data Structures and Algorithms
Data Structures and Algorithms
Efficient conflict driven learning in a boolean satisfiability solver
Proceedings of the 2001 IEEE/ACM international conference on Computer-aided design
Applying SAT Methods in Unbounded Symbolic Model Checking
CAV '02 Proceedings of the 14th International Conference on Computer Aided Verification
DATE '03 Proceedings of the conference on Design, Automation and Test in Europe - Volume 1
Verification of Proofs of Unsatisfiability for CNF Formulas
DATE '03 Proceedings of the conference on Design, Automation and Test in Europe - Volume 1
Strong conflict analysis for propositional satisfiability
Proceedings of the conference on Design, automation and test in Europe: Proceedings
SAT sweeping with local observability don't-cares
Proceedings of the 43rd annual Design Automation Conference
Increasing the deducibility in CNF instances for efficient SAT-based bounded model checking
HLDVT '05 Proceedings of the High-Level Design Validation and Test Workshop, 2005. on Tenth IEEE International
Alembic: an efficient algorithm for CNF preprocessing
Proceedings of the 44th annual Design Automation Conference
An Incremental Algorithm to Check Satisfiability for Bounded Model Checking
Electronic Notes in Theoretical Computer Science (ENTCS)
NiVER: non-increasing variable elimination resolution for preprocessing SAT instances
SAT'04 Proceedings of the 7th international conference on Theory and Applications of Satisfiability Testing
Effective preprocessing in SAT through variable and clause elimination
SAT'05 Proceedings of the 8th international conference on Theory and Applications of Satisfiability Testing
On subsumption removal and on-the-fly CNF simplification
SAT'05 Proceedings of the 8th international conference on Theory and Applications of Satisfiability Testing
Complete SAT solver based on set theory
ICICA'12 Proceedings of the Third international conference on Information Computing and Applications
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Satisfiability (SAT) solvers often benefit from transformations of the formula to be decided that allow them to do more through deduction and decrease their reliance on enumeration. For formulae in conjunctive normal form, subsumed clauses may be removed or partial resolution may be applied. The objectives of simplifying the formula and speeding up the solver are sometimes competing. We characterize existing transformations in terms of their impact on the deductive power of the formula and their effects on the sizes of the implication graphs. For example, we show that variable elimination works by improving implication graphs. We also present two new techniques that try to increase deductive power. The first is a check performed during the computation of resolvents. The second is a new preprocessing algorithm based on distillation that combines simplification and increase of deductive power. Most current SAT solvers apply resolution at various stages to derive new clauses or simplify existing ones. The former happens during conflict analysis, while the latter is usually done during preprocessing. We show how subsumption of the operands by the resolvent can be inexpensively detected during resolution; we then discuss how this detection is used to improve three stages of the SAT solver: variable elimination, clause distillation, and conflict analysis. The "on-the-fly" subsumption check is easily integrated in a SAT solver. In particular, it is compatible with strong conflict analysis and the generation of unsatisfiability proofs. Experiments show the effectiveness of the new techniques.