| 摘要 |
PURPOSE:To execute the detection of overflow and underflow at high speed by performing rounding processing on mantissa data, and outputting the boundary value of the overflow or underflow of each size selected based on the most significant bit of exponent data. CONSTITUTION:The mantissa data is supplied to a control signal generation circuit 1 and a barrel shifter 2, and the output of the barrel shifter 2 is supplied to a bit pattern detection circuit 11 and an adder 4, and a size signal and a control signal of rounding method are supplied from the outside to the pattern detection circuit 11. Then, exponent correction is performed by normalizing the mantissa part of non-normalization data, and the rounding processing is performed on the data of the mantissa part, and the boundary value of the overflow or underflow of each size is outputted based on data size and the most significant bit of the exponent data. In such a way, it is possible to perform the detection of the overflow or underflow at high speed by discriminating possibility even when data of different size are mixed. |
