third_party/lzma_sdk/LzHash.h

   1 /* LzHash.h -- HASH functions for LZ algorithms
   2 2009-02-07 : Igor Pavlov : Public domain */
   3
   4 #ifndef __LZ_HASH_H
   5 #define __LZ_HASH_H
   6
   7 #define kHash2Size (1 << 10)
   8 #define kHash3Size (1 << 16)
   9 #define kHash4Size (1 << 20)
  10
  11 #define kFix3HashSize (kHash2Size)
  12 #define kFix4HashSize (kHash2Size + kHash3Size)
  13 #define kFix5HashSize (kHash2Size + kHash3Size + kHash4Size)
  14
  15 #define HASH2_CALC hashValue = cur[0] | ((UInt32)cur[1] << 8);
  16
  17 #define HASH3_CALC { \
  18   UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
  19   hash2Value = temp & (kHash2Size - 1); \
  20   hashValue = (temp ^ ((UInt32)cur[2] << 8)) & p->hashMask; }
  21
  22 #define HASH4_CALC { \
  23   UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
  24   hash2Value = temp & (kHash2Size - 1); \
  25   hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \
  26   hashValue = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & p->hashMask; }
  27
  28 #define HASH5_CALC { \
  29   UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
  30   hash2Value = temp & (kHash2Size - 1); \
  31   hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \
  32   hash4Value = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)); \
  33   hashValue = (hash4Value ^ (p->crc[cur[4]] << 3)) & p->hashMask; \
  34   hash4Value &= (kHash4Size - 1); }
  35
  36 /* #define HASH_ZIP_CALC hashValue = ((cur[0] | ((UInt32)cur[1] << 8)) ^ p->crc[cur[2]]) & 0xFFFF; */
  37 #define HASH_ZIP_CALC hashValue = ((cur[2] | ((UInt32)cur[0] << 8)) ^ p->crc[cur[1]]) & 0xFFFF;
  38
  39
  40 #define MT_HASH2_CALC \
  41   hash2Value = (p->crc[cur[0]] ^ cur[1]) & (kHash2Size - 1);
  42
  43 #define MT_HASH3_CALC { \
  44   UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
  45   hash2Value = temp & (kHash2Size - 1); \
  46   hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); }
  47
  48 #define MT_HASH4_CALC { \
  49   UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
  50   hash2Value = temp & (kHash2Size - 1); \
  51   hash3Value = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); \
  52   hash4Value = (temp ^ ((UInt32)cur[2] << 8) ^ (p->crc[cur[3]] << 5)) & (kHash4Size - 1); }
  53
  54 #endif