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Compiler-specific Features
Errors
The compiler does not recognize the __sev intrinsic when compiling for a target that
does not support the SEV instruction. The compiler generates either a warning or an error
in this case.
See also
• __nop on page 4-89
• __wfe on page 4-107
• __wfi on page 4-107
• __yield on page 4-108
• NOP, SEV, WFE, WFI, and YIELD on page 4-142 in the Assembler Guide.
4.7.33 __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.
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