1 /******************************************************************************/ 2 #ifdef JEMALLOC_H_TYPES 3 4 #endif /* JEMALLOC_H_TYPES */ 5 /******************************************************************************/ 6 #ifdef JEMALLOC_H_STRUCTS 7 8 #endif /* JEMALLOC_H_STRUCTS */ 9 /******************************************************************************/ 10 #ifdef JEMALLOC_H_EXTERNS 11 12 #endif /* JEMALLOC_H_EXTERNS */ 13 /******************************************************************************/ 14 #ifdef JEMALLOC_H_INLINES 15 16 #ifndef JEMALLOC_ENABLE_INLINE 17 uint64_t hash(const void *key, size_t len, uint64_t seed); 18 #endif 19 20 #if (defined(JEMALLOC_ENABLE_INLINE) || defined(JEMALLOC_HASH_C_)) 21 /* 22 * The following hash function is based on MurmurHash64A(), placed into the 23 * public domain by Austin Appleby. See http://murmurhash.googlepages.com/ for 24 * details. 25 */ 26 JEMALLOC_INLINE uint64_t 27 hash(const void *key, size_t len, uint64_t seed) 28 { 29 const uint64_t m = UINT64_C(0xc6a4a7935bd1e995); 30 const int r = 47; 31 uint64_t h = seed ^ (len * m); 32 const uint64_t *data = (const uint64_t *)key; 33 const uint64_t *end = data + (len/8); 34 const unsigned char *data2; 35 36 assert(((uintptr_t)key & 0x7) == 0); 37 38 while(data != end) { 39 uint64_t k = *data++; 40 41 k *= m; 42 k ^= k >> r; 43 k *= m; 44 45 h ^= k; 46 h *= m; 47 } 48 49 data2 = (const unsigned char *)data; 50 switch(len & 7) { 51 case 7: h ^= ((uint64_t)(data2[6])) << 48; 52 case 6: h ^= ((uint64_t)(data2[5])) << 40; 53 case 5: h ^= ((uint64_t)(data2[4])) << 32; 54 case 4: h ^= ((uint64_t)(data2[3])) << 24; 55 case 3: h ^= ((uint64_t)(data2[2])) << 16; 56 case 2: h ^= ((uint64_t)(data2[1])) << 8; 57 case 1: h ^= ((uint64_t)(data2[0])); 58 h *= m; 59 } 60 61 h ^= h >> r; 62 h *= m; 63 h ^= h >> r; 64 65 return (h); 66 } 67 #endif 68 69 #endif /* JEMALLOC_H_INLINES */ 70 /******************************************************************************/ 71