1. An arithmetic operation unit generating information representing whether or not an arithmetic operation result has been shifted when the arithmetic operation result is normalized, comprising: an arithmetic logical unit outputting the arithmetic operation result; a normalizer having a plurality of shifter normalizing the arithmetic operation result; a shift amount calculator calculating a plurality of shift amounts for said plural shifter; a predictor generating interim information that is a result of prediction of whether or not the arithmetic operation result is to be shifted when the arithmetic operation result is normalized, by using the plural shift amounts; and a generator generating the information by using the interim information.