server-skynet-source-3rd-je.../include/jemalloc/internal/hash.h

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/******************************************************************************/
#ifdef JEMALLOC_H_TYPES
#endif /* JEMALLOC_H_TYPES */
/******************************************************************************/
#ifdef JEMALLOC_H_STRUCTS
#endif /* JEMALLOC_H_STRUCTS */
/******************************************************************************/
#ifdef JEMALLOC_H_EXTERNS
#endif /* JEMALLOC_H_EXTERNS */
/******************************************************************************/
#ifdef JEMALLOC_H_INLINES
#ifndef JEMALLOC_ENABLE_INLINE
uint64_t hash(const void *key, size_t len, uint64_t seed);
#endif
#if (defined(JEMALLOC_ENABLE_INLINE) || defined(JEMALLOC_HASH_C_))
/*
* The following hash function is based on MurmurHash64A(), placed into the
* public domain by Austin Appleby. See http://murmurhash.googlepages.com/ for
* details.
*/
JEMALLOC_INLINE uint64_t
hash(const void *key, size_t len, uint64_t 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);
const unsigned char *data2;
assert(((uintptr_t)key & 0x7) == 0);
while(data != end) {
uint64_t k = *data++;
k *= m;
k ^= k >> r;
k *= m;
h ^= k;
h *= m;
}
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;
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return (h);
}
#endif
#endif /* JEMALLOC_H_INLINES */
/******************************************************************************/