| 摘要 |
PURPOSE:To shorten the processing time by finding out the valid digits of an operated value and an operand, deciding whether the valid digits can be processed with an operational instruction included in a hardware or not, and in the possible case, using the operational instruction to execute the processing with one operational instruction without referring to invalid digits. CONSTITUTION:Operated value valid digit calculating processing 1 and operand valid digit calculating processing 2 respectively execute inspections up to the appearance of a valid value in each area constituting one digit from the upper digits of respectively applied operated value and operand. Invalid digits are respectively subtracted from the whole digits of the operated value and the operand to find out the valid digits of the operated value and the operand. Processing system deciding processing 3 decides whether the valid digits of the operated value and the operand respectively found out by the processing 1, 2 are the number of digits to be processed by a decimal data operational instruction included in the hardware or not. When the processing is possible, the step 3 is branched to instruction combining operation processing 5. The instruction processing 4 uses the decimal data operational instruction included in the hardware and the operational processing 5 executes respective dyadic operation processing by hardware instruction combining processing based upon the operated value and the operand. |
