Architectural retiming: pipelining latency-constrained circuits

This paper presents a new optimization technique called architectural retiming which is able to improve the performance of many latency-constrained circuits. Architectural retiming achieves this by increasing the number of registers on the latency-constrained path while preserving the functionality and latency of the circuit. This is done using the concept of a negative register, which can be implemented using precomputation and prediction. We use the name architectural retiming since it both reschedules operations in time and modifies the structure of the circuit to preserve its functionality. We illustrate the use of architectural retiming on two realistic examples and present performance improvement results for a number of sample circuits