4.7.36. __sqrt

This intrinsic inserts a VFP VSQRT instruction into the instruction stream generated by the compiler. It enables you to obtain the square root of a double-precision floating-point value from within your C or C++ code.

Note

The __sqrt intrinsic is an analogue of the standard C library function sqrt. It differs from the standard library function in that a call to __sqrt is guaranteed to be compiled into a single, inline, machine instruction on an ARM architecture-based processor equipped with a VFP coprocessor.

Syntax

double __sqrt(double val)

Where:

val

is a double-precision floating-point value.

Return value

The __sqrt intrinsic returns the square root of val as a double.

Errors

The compiler does not recognize the __sqrt intrinsic when compiling for a target that is not equipped with a VFP coprocessor. The compiler generates either a warning or an error in this case.

See also

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