Actual source code: hashtable.h

  1: #ifndef PETSC_HASHTABLE_H
  2: #define PETSC_HASHTABLE_H

  4: #include <petsc/private/petscimpl.h>

  6: #define kh_inline   inline
  7: #define klib_unused PETSC_UNUSED
  8: #include <petsc/private/khash/khash.h>

 10: /* Required for khash <= 0.2.5 */
 11: #if !defined(kcalloc)
 12:   #define kcalloc(N, Z) calloc(N, Z)
 13: #endif
 14: #if !defined(kmalloc)
 15:   #define kmalloc(Z) malloc(Z)
 16: #endif
 17: #if !defined(krealloc)
 18:   #define krealloc(P, Z) realloc(P, Z)
 19: #endif
 20: #if !defined(kfree)
 21:   #define kfree(P) free(P)
 22: #endif

 24: /* --- Useful extensions to khash --- */

 26: #if !defined(kh_reset)
 27:   /*! @function
 28:   @abstract     Reset a hash table to initial state.
 29:   @param  name  Name of the hash table [symbol]
 30:   @param  h     Pointer to the hash table [khash_t(name)*]
 31:  */
 32:   #define kh_reset(name, h) \
 33:     { \
 34:       if (h) { \
 35:         kfree((h)->keys); \
 36:         kfree((h)->flags); \
 37:         kfree((h)->vals); \
 38:         memset((h), 0x00, sizeof(*(h))); \
 39:       } \
 40:     }
 41: #endif /*kh_reset*/

 43: #if !defined(kh_foreach)
 44:   /*! @function
 45:   @abstract     Iterate over the entries in the hash table
 46:   @param  h     Pointer to the hash table [khash_t(name)*]
 47:   @param  kvar  Variable to which key will be assigned
 48:   @param  vvar  Variable to which value will be assigned
 49:   @param  code  Block of code to execute
 50:  */
 51:   #define kh_foreach(h, kvar, vvar, code) \
 52:     { \
 53:       khint_t __i; \
 54:       for (__i = kh_begin(h); __i != kh_end(h); ++__i) { \
 55:         if (!kh_exist(h, __i)) continue; \
 56:         (kvar) = kh_key(h, __i); \
 57:         (vvar) = kh_val(h, __i); \
 58:         code; \
 59:       } \
 60:     }
 61: #endif /*kh_foreach*/

 63: #if !defined(kh_foreach_key)
 64:   /*! @function
 65:   @abstract     Iterate over the keys in the hash table
 66:   @param  h     Pointer to the hash table [khash_t(name)*]
 67:   @param  kvar  Variable to which key will be assigned
 68:   @param  code  Block of code to execute
 69:  */
 70:   #define kh_foreach_key(h, kvar, code) \
 71:     { \
 72:       khint_t __i; \
 73:       for (__i = kh_begin(h); __i != kh_end(h); ++__i) { \
 74:         if (!kh_exist(h, __i)) continue; \
 75:         (kvar) = kh_key(h, __i); \
 76:         code; \
 77:       } \
 78:     }
 79: #endif /*kh_foreach_key*/

 81: #if !defined(kh_foreach_value)
 82:   /*! @function
 83:   @abstract     Iterate over the values in the hash table
 84:   @param  h     Pointer to the hash table [khash_t(name)*]
 85:   @param  vvar  Variable to which value will be assigned
 86:   @param  code  Block of code to execute
 87:  */
 88:   #define kh_foreach_value(h, vvar, code) \
 89:     { \
 90:       khint_t __i; \
 91:       for (__i = kh_begin(h); __i != kh_end(h); ++__i) { \
 92:         if (!kh_exist(h, __i)) continue; \
 93:         (vvar) = kh_val(h, __i); \
 94:         code; \
 95:       } \
 96:     }
 97: #endif /*kh_foreach_value*/

 99: /* --- Helper macro for error checking --- */

101: #if defined(PETSC_USE_DEBUG)
103: #else
104:   #define PetscHashAssert(expr) ((void)(expr))
105: #endif

107: /* --- Low level iterator API --- */

109: typedef khiter_t PetscHashIter;

111: #define PetscHashIterBegin(ht, i) \
112:   do { \
113:     (i) = kh_begin((ht)); \
114:     if ((i) != kh_end((ht)) && !kh_exist((ht), (i))) PetscHashIterNext((ht), (i)); \
115:   } while (0)

117: #define PetscHashIterNext(ht, i) \
118:   do { \
119:     ++(i); \
120:   } while ((i) != kh_end((ht)) && !kh_exist((ht), (i)))

122: #define PetscHashIterAtEnd(ht, i) ((i) == kh_end((ht)))

124: #define PetscHashIterGetKey(ht, i, k) ((k) = kh_key((ht), (i)))

126: #define PetscHashIterGetVal(ht, i, v) ((v) = kh_val((ht), (i)))

128: #define PetscHashIterSetVal(ht, i, v) (kh_val((ht), (i)) = (v))

130: /* --- Thomas Wang integer hash functions --- */

132: typedef khint32_t PetscHash32_t;
133: typedef khint64_t PetscHash64_t;
134: typedef khint_t   PetscHash_t;

136: /* Thomas Wang's first version for 32bit integers */
137: static inline PetscHash_t PetscHash_UInt32_v0(PetscHash32_t key)
138: {
139:   key += ~(key << 15);
140:   key ^= (key >> 10);
141:   key += (key << 3);
142:   key ^= (key >> 6);
143:   key += ~(key << 11);
144:   key ^= (key >> 16);
145:   return key;
146: }

148: /* Thomas Wang's second version for 32bit integers */
149: static inline PetscHash_t PetscHash_UInt32_v1(PetscHash32_t key)
150: {
151:   key = ~key + (key << 15); /* key = (key << 15) - key - 1; */
152:   key = key ^ (key >> 12);
153:   key = key + (key << 2);
154:   key = key ^ (key >> 4);
155:   key = key * 2057; /* key = (key + (key << 3)) + (key << 11); */
156:   key = key ^ (key >> 16);
157:   return key;
158: }

160: static inline PetscHash_t PetscHash_UInt32(PetscHash32_t key)
161: {
162:   return PetscHash_UInt32_v1(key);
163: }

165: /* Thomas Wang's version for 64bit integer -> 32bit hash */
166: static inline PetscHash32_t PetscHash_UInt64_32(PetscHash64_t key)
167: {
168:   key = ~key + (key << 18); /* key = (key << 18) - key - 1; */
169:   key = key ^ (key >> 31);
170:   key = key * 21; /* key = (key + (key << 2)) + (key << 4);  */
171:   key = key ^ (key >> 11);
172:   key = key + (key << 6);
173:   key = key ^ (key >> 22);
174:   return (PetscHash32_t)key;
175: }

177: /* Thomas Wang's version for 64bit integer -> 64bit hash */
178: static inline PetscHash64_t PetscHash_UInt64_64(PetscHash64_t key)
179: {
180:   key = ~key + (key << 21); /* key = (key << 21) - key - 1; */
181:   key = key ^ (key >> 24);
182:   key = key * 265; /* key = (key + (key << 3)) + (key << 8);  */
183:   key = key ^ (key >> 14);
184:   key = key * 21; /* key = (key + (key << 2)) + (key << 4); */
185:   key = key ^ (key >> 28);
186:   key = key + (key << 31);
187:   return key;
188: }

190: static inline PetscHash_t PetscHash_UInt64(PetscHash64_t key)
191: {
192:   return sizeof(PetscHash_t) < sizeof(PetscHash64_t) ? (PetscHash_t)PetscHash_UInt64_32(key) : (PetscHash_t)PetscHash_UInt64_64(key);
193: }

195: static inline PetscHash_t PetscHashInt(PetscInt key)
196: {
197: #if defined(PETSC_USE_64BIT_INDICES)
198:   return PetscHash_UInt64((PetscHash64_t)key);
199: #else
200:   return PetscHash_UInt32((PetscHash32_t)key);
201: #endif
202: }

204: static inline PetscHash_t PetscHashPointer(void *key)
205: {
206: #if PETSC_SIZEOF_VOID_P == 8
207:   return PetscHash_UInt64((PetscHash64_t)key);
208: #else
209:   return PetscHash_UInt32((PetscHash32_t)key);
210: #endif
211: }

213: static inline PetscHash_t PetscHashCombine(PetscHash_t seed, PetscHash_t hash)
214: {
215:   /* https://doi.org/10.1002/asi.10170 */
216:   /* https://dl.acm.org/citation.cfm?id=759509 */
217:   return seed ^ (hash + (seed << 6) + (seed >> 2));
218: }

220: #define PetscHashEqual(a, b) ((a) == (b))

222: #endif /* PETSC_HASHTABLE_H */