Piparazzi: A test program generator for micro-architecture flow verification

Abstract

Because of their complexity, modern microprocessors need new tools that generate tests for micro-architectural events. Piparazzi is a test generator, developed at IBM, that generates (architectural) test programs for microarchitectural events. Piparazzi uses a declarative model of the micro-architecture and the user's definition of the required event to create an instance of a Constraint Satisfaction Problem (CSP). It then uses a dedicated CSP solver to generate a test program that covers the specific event. We show how Piparazzi yields significant improvements in covering micro-architectural events, by describing its technology and by exhibiting experimental results. Piparazzi has already been successful in finding both functional and performance bugs that could only be discovered using an exact micro-architectural model of the processor.