bits set counting and iteration

bits.cpp

#include <stdint.h>
#include <stdio.h>


int main(int argc, char* argv[])
{
	uint32_t value = 0x8421;

	uint32_t out   = 0;
	uint32_t bits  = 0;

	for (bits = value, out = 0; bits; bits &= (bits - 1), out++)
		printf("bits: 0x%08x count: %02d\n", bits, out);

	bits = value;
	do
	{
		out   = bits;
		bits &= bits - 1;
		out  &= ~bits;
		printf("bits: 0x%08x out: 0x%08x %d\n", bits, out, out);
	} while (bits);

	return 0;
}