Abstract. ABC is a public-domain system for logic synthesis and formal verification of binary logic circuits appearing in synchronous hardware designs. ABC combines scalable logic transformations based on And-Inverter Graphs (AIGs), with a variety of innovative algorithms. A focus on the synergy of sequential synthesis and sequential verification leads to improvements in both domains. This paper introduces ABC, motivates its development, and illustrates its use in formal verification.

An improved method for speculative reduction is proposed and applied to (suspected) hard verification problems. Several variations of the algorithm were tested: (a) applying speculation initially to the original problem; (b) applying speculation after simplification, before our regular model checker, super_prove is applied, as well as (c) using different filters to reduce the number of speculated equivalences tried. On the benchmarks coming from sequential equivalence checking, the speculationfirst strategy with filtering proved to be faster than super_prove. On other benchmarks that may have come from property checking, super_prove is found superior. 1

the first truly new bit-level symbolic model checking algorithm since Ken McMillan’s interpolation based model checking procedure introduced in 2003. Our experience with the algorithm suggests that it is stronger than interpolation on industrial problems, and that it is an important algorithm to study further. In this paper, we present a simplified and faster implementation of Bradley’s procedure, and discuss our successful and unsuccessful attempts to improve it. I.

Model checking (MC) offers an application amenable to the use of concurrency in some innovative ways. In this paper we focus on solving single, hard properties, and show how concurrency can be used to orchestrate the MC engines in a more robust way compared to traditional, non-concurrent solutions. Through a Python front-end to ABC, with concurrency capabilities, we demonstrate enhanced performance on both academic and industrial problems. 2