An Effective Verification Solution for Modern Microprocessors.

Over the past four decades microprocessors have come to be a vital and inseparable part of the modern world, becoming the digital brain of numerous electronic devices and gadgets that make today's lifestyle possible. Processors are capable of performing computation at astonishingly high speeds and are extremely integrated, occupying only a few square centimeters of silicon die. However, this computational power comes at a price: the task of verifying a modern microprocessor and guaranteeing correctness of its operation is increasingly challenging, even for most established processor vendors. Always attempting to deliver higher performance to end-users, processor manufacturers are forced to design progressively more complex circuits and employ immense verification teams to eliminate critical design bugs in a timely manner. Unfortunately, too often size doesn't seem to matter in verification, as schedules continue to slip and microprocessors find their way to the marketplace with design errors. This work describes a novel verification framework targeting specifically today's complex microprocessors. The scope of the work spans many levels of verification and different phases of the processor life-cycle, from validation of individual sub-modules to complete multi-core system, and from pre-silicon design verification to in-the-field hardware patching. In particular, our StressTest and MCjammer approaches enable efficient generation of high-quality tests at the pre-silicon level for individual cores and multi-core systems, respectively, using machine learning techniques and making the process as automatic as possible. On the other hand, Reversi and Dacota enable low cost validation in post-silicon, while delivering even higher coverage than pre-silicon techniques. Finally, the Field-repairable control logic (FRCL) and Caspar techniques allow designers to patch different classes of escaped errors in processors that are deployed in the field. The integrated set of solutions that we introduce with this thesis empowers processor vendors to drastically shorten their development timeline and, at the same time, to deliver more reliable and correct systems to their customers at a lower cost. Altogether, this work has the potential to solve the long-standing challenge of guaranteeing the complete functional correctness of modern microprocessors.PhDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/61656/1/ivagner_1.pd