Date: 2022-03-31T04:49:13+00:00

Actual source code: hashtable.h

      1: #if !defined(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:         if (h) {                                                \
     34:                 kfree((h)->keys); kfree((h)->flags);            \
     35:                 kfree((h)->vals);                               \
     36:                 memset((h), 0x00, sizeof(*(h)));                \
     37:         } }
     38: #endif /*kh_reset*/

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

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

     72: #if !defined(kh_foreach_value)
     73: /*! @function
     74:   @abstract     Iterate over the values in the hash table
     75:   @param  h     Pointer to the hash table [khash_t(name)*]
     76:   @param  vvar  Variable to which value will be assigned
     77:   @param  code  Block of code to execute
     78:  */
     79: #define kh_foreach_value(h, vvar, code) { khint_t __i;          \
     80:         for (__i = kh_begin(h); __i != kh_end(h); ++__i) {      \
     81:                 if (!kh_exist(h,__i)) continue;                 \
     82:                 (vvar) = kh_val(h,__i);                         \
     83:                 code;                                           \
     84:         } }
     85: #endif /*kh_foreach_value*/

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

     89: #if defined(PETSC_USE_DEBUG)
     91: #else
     92: #define PetscHashAssert(expr) ((void)(expr))
     93: #endif

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

     97: typedef khiter_t PetscHashIter;

     99: #define PetscHashIterBegin(ht,i) do {              \
    100:   (i) = kh_begin((ht));                            \
    101:   if ((i) != kh_end((ht)) && !kh_exist((ht),(i)))  \
    102:     PetscHashIterNext((ht),(i));                   \
    103: } while (0)

    105: #define PetscHashIterNext(ht,i) \
    106:   do { ++(i); } while ((i) != kh_end((ht)) && !kh_exist((ht),(i)))

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

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

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

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

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

    118: typedef khint32_t PetscHash32_t;
    119: typedef khint64_t PetscHash64_t;
    120: typedef khint_t   PetscHash_t;

    122: /* Thomas Wang's first version for 32bit integers */
    123: static inline PetscHash_t PetscHash_UInt32_v0(PetscHash32_t key)
    124: {
    125:   key += ~(key << 15);
    126:   key ^=  (key >> 10);
    127:   key +=  (key <<  3);
    128:   key ^=  (key >>  6);
    129:   key += ~(key << 11);
    130:   key ^=  (key >> 16);
    131:   return key;
    132: }

    134: /* Thomas Wang's second version for 32bit integers */
    135: static inline PetscHash_t PetscHash_UInt32_v1(PetscHash32_t key)
    136: {
    137:   key = ~key + (key << 15); /* key = (key << 15) - key - 1; */
    138:   key =  key ^ (key >> 12);
    139:   key =  key + (key <<  2);
    140:   key =  key ^ (key >>  4);
    141:   key =  key * 2057;        /* key = (key + (key << 3)) + (key << 11); */
    142:   key =  key ^ (key >> 16);
    143:   return key;
    144: }

    146: static inline PetscHash_t PetscHash_UInt32(PetscHash32_t key)
    147: {
    148:   return PetscHash_UInt32_v1(key);
    149: }

    151: /* Thomas Wang's version for 64bit integer -> 32bit hash */
    152: static inline PetscHash32_t PetscHash_UInt64_32(PetscHash64_t key)
    153: {
    154:   key = ~key + (key << 18); /* key = (key << 18) - key - 1; */
    155:   key =  key ^ (key >> 31);
    156:   key =  key * 21;          /* key = (key + (key << 2)) + (key << 4);  */
    157:   key =  key ^ (key >> 11);
    158:   key =  key + (key <<  6);
    159:   key =  key ^ (key >> 22);
    160:   return (PetscHash32_t)key;
    161: }

    163: /* Thomas Wang's version for 64bit integer -> 64bit hash */
    164: static inline PetscHash64_t PetscHash_UInt64_64(PetscHash64_t key)
    165: {
    166:   key = ~key + (key << 21); /* key = (key << 21) - key - 1; */
    167:   key =  key ^ (key >> 24);
    168:   key =  key * 265;         /* key = (key + (key << 3)) + (key << 8);  */
    169:   key =  key ^ (key >> 14);
    170:   key =  key * 21;          /* key = (key + (key << 2)) + (key << 4); */
    171:   key =  key ^ (key >> 28);
    172:   key =  key + (key << 31);
    173:   return key;
    174: }

    176: static inline PetscHash_t PetscHash_UInt64(PetscHash64_t key)
    177: {
    178:   return sizeof(PetscHash_t) < sizeof(PetscHash64_t)
    179:     ? (PetscHash_t)PetscHash_UInt64_32(key)
    180:     : (PetscHash_t)PetscHash_UInt64_64(key);
    181: }

    183: static inline PetscHash_t PetscHashInt(PetscInt key)
    184: {
    185: #if defined(PETSC_USE_64BIT_INDICES)
    186:   return PetscHash_UInt64((PetscHash64_t)key);
    187: #else
    188:   return PetscHash_UInt32((PetscHash32_t)key);
    189: #endif
    190: }

    192: static inline PetscHash_t PetscHashPointer(void *key)
    193: {
    194: #if PETSC_SIZEOF_VOID_P == 8
    195:   return PetscHash_UInt64((PetscHash64_t)key);
    196: #else
    197:   return PetscHash_UInt32((PetscHash32_t)key);
    198: #endif
    199: }

    201: static inline PetscHash_t PetscHashCombine(PetscHash_t seed, PetscHash_t hash)
    202: {
    203:   /* https://doi.org/10.1002/asi.10170 */
    204:   /* https://dl.acm.org/citation.cfm?id=759509 */
    205:   return seed ^ (hash + (seed << 6) + (seed >> 2));
    206: }

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

    210: #endif /* PETSC_HASHTABLE_H */