The concept of improving the timing behavior of a circuit by relocating registers is called retiming and was first presented by Leiserson and Saxe. They showed that the problem of determining an equivalent minimum area (total number of registers) circuit is polynomial-time solvable. In this work we show how this approach can be reapplied in the DSM domain when area-delay trade-offs and delay constraints are considered. The main result is that the concavity of the trade-off function allows for a casting of this DSM problem into a classical minimum area retiming problem whose solution is polynomial time solvable.
Abdallah Tabbara, Robert K. Brayton, A. Richard Ne