Abstract: An apparatus and method for calculating a square root of an operand in a microprocessor are provided. The microprocessor has a plurality of square root instructions, each of which specifies a square root calculation precision. The apparatus includes translation logic and execution logic. The translation logic decodes the square root macro instruction into a plurality of prescribed-precision machine instructions according to the square root calculation precision specified by the plurality of square root instructions. The execution logic, coupled to the translation logic, receives the plurality of prescribed-precision machine instructions and calculates the square root of the operand according to the specified square root calculation precision. At least one of the plurality of square root instructions specifies the square root calculation precision such that less significant bits are calculated in the square root than are provided in the operand.