Boolean Equi-propagation for Optimized SAT Encoding

  • Amit Metodi
  • Michael Codish
  • Vitaly Lagoon
  • Peter J. Stuckey
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6876)


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.


Boolean Function Unit Propagation Integer Variable Boolean Formula Binary Decision Diagram 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Amit Metodi
    • 1
  • Michael Codish
    • 1
  • Vitaly Lagoon
    • 2
  • Peter J. Stuckey
    • 3
  1. 1.Department of Computer ScienceBen Gurion University of the NegevIsrael
  2. 2.Cadence Design SystemsUSA
  3. 3.Department of Computer Science and Software Engineering, and NICTA Victoria LaboratoryThe University of MelbourneAustralia

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