Report Number: CSL-TR-95-668
Institution: Stanford University, Computer Systems Laboratory
Title: Architecture Evaluator's Work Bench and its Application to Microprocessor Floating Point Units
Author: Fu, Steve
Author: Quach, Nhon
Author: Flynn, Michael
Date: June 1995
Abstract: This paper introduces Architecture Evaluator's Workbench(AEWB), a high level design space exploration methodology, and its application to floating point units(FPUs). In applying AEWB to FPUs, a metric for optimizing and comparing FPU implementations is developed. The metric -- FUPA incorporates four aspects of AEWB -- latency, cost, technology and profiles of target applications. FUPA models latency in terms of delay, cost in terms of area, and profile in terms of percentage of different floating point operations. We utilize sub-micron device models, interconnect models, and actual microprocessor scaling data to develop models used to normalize both latency and area enabling technology-independent comparison of implementations. This report also surveys most of the state of the art microprocessors, and compares them utilizing FUPA. Finally, we correlate the FUPA results to reported SPECfp92 results, and demonstrate the effect of circuit density on FUPA implementations.