Techniques for the synthesis of reversible Toffoli networks

Abstract

We present certain new techniques for the synthesis of reversible networks of Toffoli gates, as well as improvements to previous methods. Gate count and technology oriented cost metrics are used. Two new synthesis procedures employing Reed-Muller spectra are introduced and shown to complement earlier synthesis approaches. The previously proposed template simplification method is enhanced through the introduction of a faster and more efficient template application algorithm, an updated classification of the templates, and the addition of new templates of sizes 7 and 9. A resynthesis approach is introduced wherein a sequence of gates is chosen from a network, and the reversible specification it realizes is resynthesized as an independent problem in hopes of reducing the network cost. Empirical results are presented to show that the methods are efficient in terms of the realization of reversible benchmark specifications.