Preprocessing and Inprocessing Techniques in SAT

Abstract

SAT solvers are used in many applications in and outside of Computer Science. The success of SAT is based on the use of good decision heuristics, learning, restarts, and compact data structures with fast algorithms. But also efficient and effective encoding, preprocessing and inprocessing techniques are important in practice. In this talk we give an overview of old and more recent inprocessing and preprocessing techniques starting with ancient pure literal reasoning and failed literal probing. Hyper-binary resolution and variable elimination are more recent techniques of this century. We discuss blocked-clause elimination, which gives a nice connection to optimizing encodings and conclude with our recent results on unhiding redundancy fast.

Speaker Bio

Since 2004 Prof. Armin Biere chairs the Institute for Formal Models and Verification at the Johannes Kepler University in Linz, Austria. Between 2000 and 2004 he held a position as Assistant Professor within the Department of Computer Science at ETH Zürich, Switzerland. In 1999 Biere was working for a start-up company in electronic design automation after one year as Post-Doc with Edmund Clarke at CMU, Pittsburgh, USA. In 1997 Biere received a Ph.D. in Computer Science from the University of Karlsruhe, Germany.

His primary research interests are applied formal methods, more specifically formal verification of hardware and software, using model checking, propositional and related techniques. He is the author and co-author of more than 60 papers and served on the program committee of more than 45 international workshops and conferences. His highest influential work is the contribution to Bounded Model Checking. Decision procedures for SAT, QBF and SMT, developed by him or under his guidance rank at the top of many international competitions. Besides organizing several workshops Armin Biere was co-chair of SAT’06 and FMCAD’09. He is on the editorial board of the Journal on Satisfiability, Boolean Modeling and Computation (JSAT), and is one of the editors of the Handbook of Satisfiability. He also organizes the Hardware Model Checking Competition.