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Compiler-specific Features
Syntax
void __enable_irq(void)
Restrictions
The __enable_irq intrinsic can only be executed in privileged modes, that is, in non user
modes. In User mode this intrinsic does not change the interrupt flags in the CPSR.
See also
• __disable_irq on page 4-80.
4.7.11 __fabs
This intrinsic inserts a VABS instruction or an equivalent code sequence into the
instruction stream generated by the compiler. It enables you to obtain the absolute value
of a double-precision floating-point value from within your C or C++ code.
Note
The __fabs intrinsic is an analogue of the standard C library function fabs. It differs
from the standard library function in that a call to __fabs is guaranteed to be compiled
into a single, inline, machine instruction on an ARM architecture-based processor
equipped with a VFP coprocessor.
Syntax
double __fabs(double val)
Where:
val
is a double-precision floating-point value.
Return value
The __fabs intrinsic returns the absolute value of val as a double.
See also
• __fabsf on page 4-84
• VABS, VNEG, and VSQRT on page 5-95 in the Assembler Guide.
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