A Circuit-Based SAT Solver for Logic Synthesis

Abstract

In recent years SAT solving has been widely used to implement various circuit transformations in logic synthesis. However, off-the-shelf CNF-based SAT solvers often have suboptimal performance on these challenging optimization problems. This paper describes an application-specific circuit-based SAT solver for logic synthesis. The solver is based on Glucose, a state-of-the-art CNF-based solver and adds a number of novel features, which make it run faster on multiple incremental SAT problems arising in redundancy removal and logic restructuring among others. In particular, the circuit structure of the problem instance is leveraged in a new way to guide variable decisions and to converge to a solution faster for both satisfiable and unsatisfiable instances. Experimental results indicate that the proposed solver leads to a 2-4x speedup, compared to the original Glucose.