Area-efficiency in CMP core design: co-optimization of microarchitecture and physical design

In this paper, we examine the area-performance design space of a processing core for a chip multiprocessor (CMP), considering both the architectural design space and the tradeoffs of the physical design on which the architecture relies. We first propose a methodology for performing an integrated optimization of both the micro-architecture and the physical circuit design of a microprocessor. In our approach, we use statistical and convex fitting methods to capture a large micro-architectural design space. We then characterize the area-delay tradeoffs of the underlying circuits through RTL synthesis. Finally, we establish the relationship between the architecture and the circuits in an integrative model, which we use to optimize the processor. As a case study, we apply this methodology to explore the performance-area tradeoffs in a highly parallel accelerator architecture for visual computing applications. Based on some early circuit tradeoff data, our results indicate that two separate designs are performance/area optimal for our set of benchmarks: a simpler single-issue, 2-way multithreaded core running at high-frequency, and a more aggressively tuned dual-issue 4-way multithreaded design running at a lower frequency.