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Compiler-specific Features
}
rtn_addr = __builtin_return_address(0); // return the lr
return rtn_addr;
See also
• __builtin_frame_address on page 4-66
• __return_address on page 4-83.
4.7.7 __builtin_popcount
This builtin function returns the population count of a specified value, that is, the
number of 1-bits in the value.
Syntax
int __builtin_popcount(unsigned int val)
Where:
val
is an unsigned integer whose population is to be counted.
Return value
__builtin_popcount returns the number of bits set to 1 in val.
Example
void foo(void)
{
int i = __builtin_popcount(3); // returns 2
int j = __builtin_popcount(5); // returns 2
int k = __builtin_popcount(8); // returns 1
}
4.7.8 __cdp
This intrinsic inserts a CDP or CDP2 instruction into the instruction stream generated by
the compiler. It enables you to include coprocessor data operations in your C or C++
code.
Syntax
__cdp(unsigned int coproc, unsigned int opcode1, unsigned int opcode2)
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