Inside Macintosh: PowerPC Numerics / Part 1 - The PowerPC Numerics Environment

Chapter 6 - Numeric Operations and Functions

Arithmetic Operations

PowerPC Numerics provides the seven arithmetic operations required by the IEEE standard for its three data types, as shown for the C language in Table 6-2 and described in the sections that follow.

Table 6-2 Arithmetic operations in C

Operation	C symbol
Add	+
Subtract	-
Multiply	*
Divide	/
Square root	sqrt
Remainder	remainder
Round-to-integer	rint

The language processors for the PowerPC automatically use their chosen expression evaluation methods for the normal inline operators (+, -, *, /). All the arithmetic operations produce the best possible result: the mathematically exact result, coerced to the precision and range of the evaluation format. The coercions honor the user-selectable rounding direction and handle all exceptions according to the requirements of the IEEE standard (see Chapter 4, "Environmental Controls").

Some of the arithmetic operations are implemented in software. These operations are declared to be type double_t, which is defined to be type double.