C5M - a control-logic layout synthesis system for high-performance microprocessors

In high-end microprocessors, control-logic timing can gate the cycle time, but control is specified late and changes often. Custom design is too time-consuming for control implementation, yet ASIC-like methods have difficulty achieving the performance/area targets. In this paper we describe C5M, a new layout system for control logic, which has been successfully used in the design of a recent 400 MHz IBM processor. Results from this design are used to show that C5M achieves near-custom quality with high productivity.