Functional test generation using design and property decomposition techniques

Abstract

Functional verification of microprocessors is one of the most complex and expensive tasks in the current system-on-chip design methodology. Simulation using functional test vectors is the most widely used form of processor validation. A significant bottleneck in the validation of such systems is the lack of automated techniques for directed test generation. While existing model checking--based approaches have proposed several promising ideas for automated test generation, many challenges remain in applying them to industrial microprocessors. The time and resources required for test generation using existing model checking--based techniques can be prohibitively large. This article presents an efficient test generation technique using decompositional model checking. The contribution of the article is the development of both property and design decomposition procedures for efficient test generation of pipelined processors. Our experimental results using a multi-issue MIPS processor and an industrial processor based on Power Architecture™ Technology demonstrate several orders-of-magnitude reduction in validation effort by drastically reducing both test generation time and test program length.