PROCESSING UNIT AND METHOD OF EXTENDING AN INSTRUCTION

摘要

An arithmetic processing unit and an extension method of a command for extending the command along a fixed length are provided to extend a register address by the restriction of an operator code length by command extension information. An XAR(eXtended Arithmetic Register) register(1) sets up command extent information indicating the expansion of a command. When the command extent information is established in the expanded register, an operation unit(5) enforces the next command of the command recording the command extent information in the expanded register to be expanded by the command extent information. A D XAR register(2) provisionally preserves a value recorded in the XAR register. An XAR change buffer(3) provisionally stores data recorded in the XAR register.