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#ifndef NUJEL_LIB_MISC_POPCOUNT
#define NUJEL_LIB_MISC_POPCOUNT
#if defined(__TINYC__) || defined(__WATCOMC__)
/* Classic binary divide-and-conquer popcount.
This is popcount_2() from
http://en.wikipedia.org/wiki/Hamming_weight */
static inline uint32_t popcount_2(uint32_t x){
uint32_t m1 = 0x55555555;
uint32_t m2 = 0x33333333;
uint32_t m4 = 0x0f0f0f0f;
x -= (x >> 1) & m1;
x = (x & m2) + ((x >> 2) & m2);
x = (x + (x >> 4)) & m4;
x += x >> 8;
return (x + (x >> 16)) & 0x3f;
}
static inline __builtin_popcountll(uint64_t x){
return popcount_2(x) + popcount_2(x >> 32);
}
#endif
#endif
