On the optimization power of redundancy addition and removal techniques for sequential circuits

This paper attempts to determine the capabilities of existing redundancy addition and removal (SRAR) techniques for logic optimization of sequential circuits. To this purpose, we compare this method with the retiming and resynthesis (RaR) techniques. For the RaR case, the set of possible transformations has been established by relating them to STG transformations by other authors. Following these works, we first formally demonstrate that logic transformations provided by RaR are covered by SRAR as well. Then, we also show that SRAR is able to identify transformations that cannot be found by RaR. This way we prove the higher potential of the sequential redundancy addition and removal techniques over the retiming and resynthesis techniques.