Automatically improving SAT encoding of constraint problems through common subexpression elimination in Savile Row
View/ Open
Date
10/2015Grant ID
EP/H004092/1
EP/M003728/1
EP/K015745/1
Metadata
Show full item recordAbstract
The formulation of a Propositional Satisfiability (SAT) problem instance is vital to efficient solving. This has motivated research on preprocessing, and inprocessing techniques where reformulation of a SAT instance is interleaved with solving. Preprocessing and inprocessing are highly effective in extending the reach of SAT solvers, however they necessarily operate on the lowest level representation of the problem, the raw SAT clauses, where higher-level patterns are difficult and/or costly to identify. Our approach is different: rather than reformulate the SAT representation directly, we apply automated reformulations to a higher level representation (a constraint model) of the original problem. Common Subexpression Elimination (CSE) is a family of techniques to improve automatically the formulation of constraint satisfaction problems, which are often highly beneficial when using a conventional constraint solver. In this work we demonstrate that CSE has similar benefits when the reformulated constraint model is encoded to SAT and solved using a state-of-the-art SAT solver. In some cases we observe speed improvements of over 100 times.
Citation
Nightingale , P , Spracklen , P & Miguel , I J 2015 , Automatically improving SAT encoding of constraint problems through common subexpression elimination in Savile Row . in G Pesant (ed.) , Principles and Practice of Constraint Programming : 21st International Conference, CP 2015, Cork, Ireland, August 31 -- September 4, 2015, Proceedings . vol. 9255 , Lecture Notes in Computer Science , vol. 9255 , Springer , pp. 330-340 , 21st International Conference on Principles and Practice of Constraint Programming (CP 2015) , Cork , Ireland , 31/08/15 . https://doi.org/10.1007/978-3-319-23219-5_23 conference
Publication
Principles and Practice of Constraint Programming
ISSN
0302-9743Type
Conference item
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.