#include <linux/export.h>#include <linux/bitops.h>#include <asm/types.h> /** * hweightN - returns the hamming weight of a N-bit word * @x: the word to weigh * * The Hamming Weight of a number is the total number of bits set in it. */ unsigned int __sw_hweight32(unsigned int w){#ifdef ARCH_HAS_FAST_MULTIPLIER	w -= (w >> 1) & 0x55555555;	w =  (w & 0x33333333) + ((w >> 2) & 0x33333333);	w =  (w + (w >> 4)) & 0x0f0f0f0f;	return (w * 0x01010101) >> 24;#else	unsigned int res = w - ((w >> 1) & 0x55555555);	res = (res & 0x33333333) + ((res >> 2) & 0x33333333);	res = (res + (res >> 4)) & 0x0F0F0F0F;	res = res + (res >> 8);	return (res + (res >> 16)) & 0x000000FF;#endif}EXPORT_SYMBOL(__sw_hweight32); unsigned int __sw_hweight16(unsigned int w){	unsigned int res = w - ((w >> 1) & 0x5555);	res = (res & 0x3333) + ((res >> 2) & 0x3333);	res = (res + (res >> 4)) & 0x0F0F;	return (res + (res >> 8)) & 0x00FF;}EXPORT_SYMBOL(__sw_hweight16); unsigned int __sw_hweight8(unsigned int w){	unsigned int res = w - ((w >> 1) & 0x55);	res = (res & 0x33) + ((res >> 2) & 0x33);	return (res + (res >> 4)) & 0x0F;}EXPORT_SYMBOL(__sw_hweight8); unsigned long __sw_hweight64(__u64 w){#if BITS_PER_LONG == 32	return __sw_hweight32((unsigned int)(w >> 32)) +	       __sw_hweight32((unsigned int)w);#elif BITS_PER_LONG == 64#ifdef ARCH_HAS_FAST_MULTIPLIER	w -= (w >> 1) & 0x5555555555555555ul;	w =  (w & 0x3333333333333333ul) + ((w >> 2) & 0x3333333333333333ul);	w =  (w + (w >> 4)) & 0x0f0f0f0f0f0f0f0ful;	return (w * 0x0101010101010101ul) >> 56;#else	__u64 res = w - ((w >> 1) & 0x5555555555555555ul);	res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul);	res = (res + (res >> 4)) & 0x0F0F0F0F0F0F0F0Ful;	res = res + (res >> 8);	res = res + (res >> 16);	return (res + (res >> 32)) & 0x00000000000000FFul;#endif#endif}EXPORT_SYMBOL(__sw_hweight64);