Patent ID: 6112018
Filing Date: 2000-08-29
Classification: G06F

Abstract:
An apparatus for exchanging two stack registers comprising:a plurality of registers, wherein said plurality of registers are configured to be accessed as a register stack;a plurality of storage locations, wherein each storage location is configured to store a pointer, wherein said pointer is configured to point to one of said plurality of registers, wherein said plurality of storage locations are configured to store one pointer for each register in said plurality of registers;a first plurality of multiplexers, wherein each multiplexer in said first plurality of multiplexers is coupled to each of said plurality of storage locations and is configured to select a particular storage location for output according to a first decoded instruction; anda second plurality of multiplexers, wherein each multiplexer in said second plurality of multiplexers is coupled to receive the output from each multiplexer in said first plurality of multiplexers, wherein each multiplexer in said second plurality of multiplexers is configured to select one of said outputs according to a second decoded instruction,wherein the contents of said plurality of storage locations define a first order of said register stack, wherein the outputs of said first plurality of multiplexers define a second order of said register stack, wherein the outputs of said second plurality of multiplexers define a third order of said register stack, wherein said plurality of storage locations are configured to receive and store the output from each multiplexer in said second plurality of multiplexers.