Design Methodology of Bidirectional Barrel Shifter Based on Reversible Logic

Abstract

Data shifting is required in many key computer operations from address decoding to computer arithmetic. Full barrel shifters are often on the critical path, which has led most research to be directed toward speed optimizations. With the advent of quantum computer and reversible logic, design and implementation of all devices in this logic has received more attention. Rotating and data shifting are required in many operations such as logical and arithmetic operations, indexing and address decoding etc. Hence barrel shifters which can shift and rotate multiple bits in a single cycle have become a common choice of design for high speed applications. The design has been done using reversible fredkin and feynman gates. In the design the 2:1 mux can be implemented by fredkin gate which reduce quantum cost, number of ancilla bits and number of garbage outputs. The feynman gate will remove the fanout. By comparing the quantum cost, number of ancilla bits and number of garbage outputs the design is evaluated.