Design of Reversible Computing Systems; Large Logic, Languages, and Circuits

Abstract

This PhD dissertation investigates garbage-free reversible computing systems from abstract design to physical gate-level implementation. Designed in reversible logic, we propose a ripple-block carry adder and work towards a reversible circuit for general multiplication. At a higher-level, abstract designs are proposed for reversible systems, such as a small von Neumann architecture that can execute programs written in a simple reversible two-address instruction set, a novel reversible arithmetic logic unit, and a linear cosine transform. To aid the design of reversible logic circuits we have designed two reversible functional hardware description languages: a linear-typed higher-level language and a gate-level point-free combinator language. We suggest a garbage-free design flow, where circuits are described in the higher-level language and then translated to the combinator language, from which methods to place-and-route of CMOS gates can be applied. We have also made standard cell layouts of the reversible gates in complementary pass-gate CMOS logic and used these to fabricate the ALU design. In total, this dissertation has shown that it is possible to design non-trivial reversible computing systems without garbage and that support from languages (computer aided design) can make this process easier.