33 research outputs found
Handling Conflicts in Depth-First Search for LTL Tableau to Debug Compliance Based Languages
Providing adequate tools to tackle the problem of inconsistent compliance
rules is a critical research topic. This problem is of paramount importance to
achieve automatic support for early declarative design and to support evolution
of rules in contract-based or service-based systems. In this paper we
investigate the problem of extracting temporal unsatisfiable cores in order to
detect the inconsistent part of a specification. We extend conflict-driven
SAT-solver to provide a new conflict-driven depth-first-search solver for
temporal logic. We use this solver to compute LTL unsatisfiable cores without
re-exploring the history of the solver.Comment: In Proceedings FLACOS 2011, arXiv:1109.239
48.2 Learning from BDDs in SAT-based Bounded Model Checking
Bounded Model Checking (BMC) based on Boolean Satisfiability (SAT) procedures has recently gained popularity as an alternative to BDD-based model checking techniques for finding bugs in large designs. In this paper, we explore the use of learning from BDDs, where learned clauses generated by BDD-based analysis are added to the SAT solver, to supplement its other learning mechanisms. We propose several heuristics for guiding this process, aimed at increasing the usefulness of the learned clauses, while reducing the overheads. We demonstrate the effectiveness of our approach on several industrial designs, where BMC performance is improved and the design can be searched up to a greater depth by use of BDD-based learning