1 /*
2 * Copyright 2012-2015 Samy Al Bahra
3 * Copyright 2011-2014 AppNexus, Inc.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #ifndef CK_HT_HASH_H
28 #define CK_HT_HASH_H
29
30 /*
31 * This is the Murmur hash written by Austin Appleby.
32 */
33
34 #include <ck_stdint.h>
35 #include <ck_string.h>
36
37 //-----------------------------------------------------------------------------
38 // MurmurHash3 was written by Austin Appleby, and is placed in the public
39 // domain. The author hereby disclaims copyright to this source code.
40
41 // Note - The x86 and x64 versions do _not_ produce the same results, as the
42 // algorithms are optimized for their respective platforms. You can still
43 // compile and run any of them on any platform, but your performance with the
44 // non-native version will be less than optimal.
45
46 //-----------------------------------------------------------------------------
47 // Platform-specific functions and macros
48
49 // Microsoft Visual Studio
50
51 #if defined(_MSC_VER)
52
53 #define FORCE_INLINE __forceinline
54
55 #include <stdlib.h>
56
57 #define ROTL32(x,y) _rotl(x,y)
58 #define ROTL64(x,y) _rotl64(x,y)
59
60 #define BIG_CONSTANT(x) (x)
61
62 // Other compilers
63
64 #else // defined(_MSC_VER)
65
66 #define FORCE_INLINE inline __attribute__((always_inline))
67
rotl32(uint32_t x,int8_t r)68 static inline uint32_t rotl32 ( uint32_t x, int8_t r )
69 {
70 return (x << r) | (x >> (32 - r));
71 }
72
rotl64(uint64_t x,int8_t r)73 static inline uint64_t rotl64 ( uint64_t x, int8_t r )
74 {
75 return (x << r) | (x >> (64 - r));
76 }
77
78 #define ROTL32(x,y) rotl32(x,y)
79 #define ROTL64(x,y) rotl64(x,y)
80
81 #define BIG_CONSTANT(x) (x##LLU)
82
83 #endif // !defined(_MSC_VER)
84
85 //-----------------------------------------------------------------------------
86 // Block read - if your platform needs to do endian-swapping or can only
87 // handle aligned reads, do the conversion here
88
getblock(const uint32_t * p,int i)89 FORCE_INLINE static uint32_t getblock ( const uint32_t * p, int i )
90 {
91 #ifdef __s390x__
92 uint32_t res;
93
94 __asm__ (" lrv %0,%1\n"
95 : "=r" (res) : "Q" (p[i]) : "cc", "mem");
96 return res;
97 #else
98 return p[i];
99 #endif /* !__s390x__ */
100 }
101
102 //-----------------------------------------------------------------------------
103 // Finalization mix - force all bits of a hash block to avalanche
104
fmix(uint32_t h)105 FORCE_INLINE static uint32_t fmix ( uint32_t h )
106 {
107 h ^= h >> 16;
108 h *= 0x85ebca6b;
109 h ^= h >> 13;
110 h *= 0xc2b2ae35;
111 h ^= h >> 16;
112
113 return h;
114 }
115
116 //-----------------------------------------------------------------------------
117
MurmurHash3_x86_32(const void * key,int len,uint32_t seed,uint32_t * out)118 static inline void MurmurHash3_x86_32 ( const void * key, int len,
119 uint32_t seed, uint32_t * out )
120 {
121 const uint8_t * data = (const uint8_t*)key;
122 const int nblocks = len / 4;
123 int i;
124
125 uint32_t h1 = seed;
126
127 uint32_t c1 = 0xcc9e2d51;
128 uint32_t c2 = 0x1b873593;
129
130 //----------
131 // body
132
133 const uint32_t * blocks = (const uint32_t *)(const void *)(data + nblocks*4);
134
135 for(i = -nblocks; i; i++)
136 {
137 uint32_t k1 = getblock(blocks,i);
138
139 k1 *= c1;
140 k1 = ROTL32(k1,15);
141 k1 *= c2;
142
143 h1 ^= k1;
144 h1 = ROTL32(h1,13);
145 h1 = h1*5+0xe6546b64;
146 }
147
148 //----------
149 // tail
150
151 const uint8_t * tail = (const uint8_t*)(data + nblocks*4);
152
153 uint32_t k1 = 0;
154
155 switch(len & 3)
156 {
157 case 3: k1 ^= tail[2] << 16;
158 /* fall through */
159 case 2: k1 ^= tail[1] << 8;
160 /* fall through */
161 case 1: k1 ^= tail[0];
162 k1 *= c1; k1 = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
163 };
164
165 //----------
166 // finalization
167
168 h1 ^= len;
169
170 h1 = fmix(h1);
171
172 *(uint32_t *)out = h1;
173 }
174
MurmurHash64A(const void * key,int len,uint64_t seed)175 static inline uint64_t MurmurHash64A ( const void * key, int len, uint64_t seed )
176 {
177 const uint64_t m = BIG_CONSTANT(0xc6a4a7935bd1e995);
178 const int r = 47;
179
180 uint64_t h = seed ^ (len * m);
181
182 const uint64_t * data = (const uint64_t *)key;
183 const uint64_t * end = data + (len/8);
184
185 while(data != end)
186 {
187 uint64_t k;
188
189 if (!((uintptr_t)data & 0x7))
190 k = *data++;
191 else {
192 memcpy(&k, data, sizeof(k));
193 data++;
194 }
195
196 k *= m;
197 k ^= k >> r;
198 k *= m;
199
200 h ^= k;
201 h *= m;
202 }
203
204 const unsigned char * data2 = (const unsigned char*)data;
205
206 switch(len & 7)
207 {
208 case 7: h ^= (uint64_t)(data2[6]) << 48;
209 /* fall through */
210 case 6: h ^= (uint64_t)(data2[5]) << 40;
211 /* fall through */
212 case 5: h ^= (uint64_t)(data2[4]) << 32;
213 /* fall through */
214 case 4: h ^= (uint64_t)(data2[3]) << 24;
215 /* fall through */
216 case 3: h ^= (uint64_t)(data2[2]) << 16;
217 /* fall through */
218 case 2: h ^= (uint64_t)(data2[1]) << 8;
219 /* fall through */
220 case 1: h ^= (uint64_t)(data2[0]);
221 h *= m;
222 };
223
224 h ^= h >> r;
225 h *= m;
226 h ^= h >> r;
227
228 return h;
229 }
230
231
232 // 64-bit hash for 32-bit platforms
233
MurmurHash64B(const void * key,int len,uint64_t seed)234 static inline uint64_t MurmurHash64B ( const void * key, int len, uint64_t seed )
235 {
236 const uint32_t m = 0x5bd1e995;
237 const int r = 24;
238
239 uint32_t h1 = (uint32_t)(seed) ^ len;
240 uint32_t h2 = (uint32_t)(seed >> 32);
241
242 const uint32_t * data = (const uint32_t *)key;
243
244 while(len >= 8)
245 {
246 uint32_t k1 = *data++;
247 k1 *= m; k1 ^= k1 >> r; k1 *= m;
248 h1 *= m; h1 ^= k1;
249 len -= 4;
250
251 uint32_t k2 = *data++;
252 k2 *= m; k2 ^= k2 >> r; k2 *= m;
253 h2 *= m; h2 ^= k2;
254 len -= 4;
255 }
256
257 if(len >= 4)
258 {
259 uint32_t k1 = *data++;
260 k1 *= m; k1 ^= k1 >> r; k1 *= m;
261 h1 *= m; h1 ^= k1;
262 len -= 4;
263 }
264
265 switch(len)
266 {
267 case 3: h2 ^= ((const unsigned char*)data)[2] << 16;
268 /* fall through */
269 case 2: h2 ^= ((const unsigned char*)data)[1] << 8;
270 /* fall through */
271 case 1: h2 ^= ((const unsigned char*)data)[0];
272 h2 *= m;
273 };
274
275 h1 ^= h2 >> 18; h1 *= m;
276 h2 ^= h1 >> 22; h2 *= m;
277 h1 ^= h2 >> 17; h1 *= m;
278 h2 ^= h1 >> 19; h2 *= m;
279
280 uint64_t h = h1;
281
282 h = (h << 32) | h2;
283
284 return h;
285 }
286
287 #endif /* CK_HT_HASH_H */
288