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#include "hash.h"
uint64_t murmur_hash_64a(void const * key, int len, unsigned int seed)
{
const uint64_t m = 0xc6a4a7935bd1e995;
const int r = 47;
uint64_t h = seed ^ (len * m);
const uint64_t * data = (const uint64_t *)key;
const uint64_t * end = data + (len/8);
while(data != end)
{
uint64_t k = *data++;
k *= m;
k ^= k >> r;
k *= m;
h ^= k;
h *= m;
}
const unsigned char * data2 = (const unsigned char*)data;
switch(len & 7)
{
case 7: h ^= (uint64_t)(data2[6]) << 48;
case 6: h ^= (uint64_t)(data2[5]) << 40;
case 5: h ^= (uint64_t)(data2[4]) << 32;
case 4: h ^= (uint64_t)(data2[3]) << 24;
case 3: h ^= (uint64_t)(data2[2]) << 16;
case 2: h ^= (uint64_t)(data2[1]) << 8;
case 1: h ^= (uint64_t)(data2[0]);
h *= m;
};
h ^= h >> r;
h *= m;
h ^= h >> r;
return h;
}
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