PURPOSE: To improve the speed of sorting processing and exception processing of input operands by providing sorting circuits and exception processing units which perform sorting processing and exception processing on input operands with their hardware.

CONSTITUTION: Input operands are classified into five attributes of zero, infinity, non-numeral, normalized numeral, and non-normalized numeral by an X-class circuit 3 and Y-class circuit 4. Each of the X-class circuit 3 and Y-class circuit 4 has a sorting circuit which generates a sorting signal in accordance with the classification. When an input operand is a special value, an operated result is outputted based on the type of operation and sorting signal. Moreover, an exception processing unit 10 which outputs results of exception processing based on the type of the operation and sorting signal designated by the sorting circuit and an external input, is provided and, when an exceptional operand is inputted, the operand or predetermined data is outputted as the operated result.