Boolean Equi-propagation for Optimized SAT Encoding
We present an approach to propagation based SAT encoding, Boolean equi-propagation, where constraints are modelled as Boolean functions which propagate information about equalities between Boolean literals. This information is then applied as a form of partial evaluation to simplify constraints prior to their encoding as CNF formulae. We demonstrate for a variety of benchmarks that our approach leads to a considerable reduction in the size of CNF encodings and subsequent speed-ups in SAT solving times.
KeywordsBoolean Function Unit Propagation Integer Variable Boolean Formula Binary Decision Diagram
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