Patent ID: 6675182
Filing Date: 2004-01-06
Classification: G06F

Abstract:
A rotator circuit comprising:an input circuit for receiving a binary input operand; multiple sets of multiplexers, coupled to said input circuit, for swapping bits of an associated input word received at an input of each of said sets of multiplexers; an output circuit, coupled to said multiple sets of multiplexers for providing a rotated binary output; and a control logic circuit, coupled to selector inputs of said multiple sets of multiplexers, wherein said control logic circuit includes a rotate amount input for controlling whether or not a particular one of said multiple sets of multiplexers swap bits between bit fields within said associated input word, so that said rotated binary output is based on a rotation by said rotate amount input of said binary input operand, wherein said control logic circuit includes a plurality of carry generators, wherein one of said plurality of carry generators is coupled to a rotate bit and to an output of a carry generator from a previous set of said multiple sets of multiplexers, wherein said control logic circuit further comprises a plurality of carry generators, each coupled to a second multiplexer from each of said multiplexer pairs, wherein each carry generator is coupled to said rotate bit and further to an output of a sum generator from a previous set of multiplexer pairs, wherein said plurality of carry generators include a plurality of OR gates.