VCEGAR: Verilog CounterExample Guided Abstraction Refinement

ion Refinement Himanshu Jain1, Daniel Kroening2, Natasha Sharygina1,3, and Edmund Clarke1 1 Carnegie Mellon University, School of Computer Science 2 ETH Zuerich, Switzerland 3 Informatics Department, University of Lugano Abstract. As first step, most model checkers used in the hardware industry convert a high-level register transfer language (RTL) design into As first step, most model checkers used in the hardware industry convert a high-level register transfer language (RTL) design into a netlist. However, algorithms that operate at the netlist level are unable to exploit the structure of the higher abstraction levels, and thus, are less scalable. The RTL level of a hardware description language such as Verilog is similar to a software program with special features for hardware design such as bit-vector arithmetic and concurrency. We describe a hardware model checking tool, VCEGAR, which performs verification at the RTL level using software verification techniques. It implements predicate abstraction and a refinement loop as used in software verification. The novel aspects are the generation of new word-level predicates, an efficient predicate image computation in presence of a large number of predicates, and precise modeling of the bit-vector semantics of hardware designs.