The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 20, 2012
Filed:
Feb. 21, 2008
Nikolaj Bjorner, Woodinville, WA (US);
Leonardo Mendonca DE Moura, Sammamish, WA (US);
Nikolaj Bjorner, Woodinville, WA (US);
Leonardo Mendonca de Moura, Sammamish, WA (US);
Microsoft Corporation, Redmond, WA (US);
Abstract
Relevancy propagation for efficient theory combination is described. In one implementation, an efficient SMT solver dynamically applies relevancy propagation to limit propagation of unnecessary constraints in a DPLL-based solver. This provides a drastic increase in speed and performance over conventional DPLL-based solvers. The relevancy propagation is guided by relevancy rules, which in one implementation emulate Tableau rules for limiting constraint propagation, while maintaining the performance of efficient DPLL-based solvers. An exemplary solver propagates truth assignments to constraints of a formula, and tracks which truth assignments are relevant for determining satisfiability of the formula. The solver propagates truth assignments that were marked relevant to a theory solver, while avoiding propagation of irrelevant truth assignments. The efficient SMT solver provides a drastic reduction in search space covered during quantifier instantiation and offers profound acceleration during bit-vectors reasoning.