Hierarchical Model Checking of SystemVerilog-Specified Asynchronous Circuits for Deadlock Detection

Abstract

Specifying channel-based asynchronous circuits in SystemVerilog is a promising alternative design paradigm to combine the advantages of asynchronous circuits and industrial electronic design automation supports. However, communicating through channels can be error-prone, potentially introducing deadlocks that cannot be detected easily through simulation. In contrast, model checking can reliably identify deadlocks, but faces challenges related to scalability and modeling capability. This research proposes a novel model checking approach, named Verilock, to detect deadlocks of channel-based asynchronous circuits specified in SystemVerilog. To address the issue of modeling capability, Verilock extracts intermodule communication behavior from SystemVerilog circuit designs and builds models in communication protocols specifically designed for this purpose. Additionally, Verilock employs a novel hierarchical model checking algorithm that conducts localized verification of well-formed groups of the system from the bottom up, thus reducing the size of the checking problems and presenting the opportunity to parallelize the checking process. Extensive experimental evaluations confirm the efficiency of Verilock in publicly accessible and randomly synthesized large-scale asynchronous circuits. Remarkably, significant benefits of the hierarchical checking approach are demonstrated through an ablative experiment.