METHOD AND APPARATUS FOR INSTRUCTION SET ARCHITECTURE TO PERFORM PRIMARY AND SHADOW DIGITAL SIGNAL PROCESSING SUB-INSTRUCTIONS SIMULTANEOUSLY

摘要

Disclosed is a method, apparatus, and an instruction set architecture (ISA) for an application specific signal processor (ASSP) tailored to digital signal processing (DSP) applications. A single DSP instruction includes a pair of sub-instructions: a primary DSP sub-instruction and a shadow DSP sub-instruction. Both the primary and the shadow DSP sub-instructions are dyadic DSP instructions performing two operations in one instruction cycle. Each signal processing unit of the ASSP includes a primary stage to execute a primary DSP sub-instruction based upon current data and a shadow stage to simultaneously execute a shadow DSP sub-instruction based upon delayed data stored locally within registers of the signal processing units. The present invention efficiently executes DSP instructions by simultaneously executing primary DSP sub-instructions (based upon current data) and shadow DSP sub-instructions (based upon delayed locally stored data) with a single DSP instruction.