System and method for assigning tags to control instruction processing in a superscalar processor

Abstract

A tag monitoring system for assigning tags to instructions embodied in software on a tangible computer-readable storage medium. A source supplies instructions to be executed by a functional unit. A queue having a plurality of slots containing tags which are used for tagging instructions. A register file stores information required for the execution of each instruction at a location in the register file defined by the tag assigned to that instruction. A control unit monitors the completion of executed instructions and advances the tags in the queue upon completion of an executed instruction. The register file also contains a plurality of read address enable ports and corresponding read output ports. Each of the slots from the queue is coupled to a corresponding one of the read address enable ports. Thus, the information for each instruction can be read out of the register file in program order.