System for selectively masking operand portions for processing thereof

摘要

A processor capable of processing data of a structure having a first information field and a second information field includes conservation means for conserving the information of the predetermined second information field of the input data. Thus, in executing a logical operation or a shift operation, the step of separating the first data fields and second data fields from the data to-be-processed and the step of affixing the predetermined second field to the result of the operation are dispensed with, thereby to achieve a high-speed operation for the data of the structure having the first information field and the second information field.