1/////////////////////////////////////////////////////////////////////////////// 2// 3/// \file lz_encoder_hash.h 4/// \brief Hash macros for match finders 5// 6// Author: Igor Pavlov 7// 8// This file has been put into the public domain. 9// You can do whatever you want with this file. 10// 11/////////////////////////////////////////////////////////////////////////////// 12 13#ifndef LZMA_LZ_ENCODER_HASH_H 14#define LZMA_LZ_ENCODER_HASH_H 15 16#if defined(WORDS_BIGENDIAN) && !defined(HAVE_SMALL) 17 // This is to make liblzma produce the same output on big endian 18 // systems that it does on little endian systems. lz_encoder.c 19 // takes care of including the actual table. 20 extern const uint32_t lzma_lz_hash_table[256]; 21# define hash_table lzma_lz_hash_table 22#else 23# include "check.h" 24# define hash_table lzma_crc32_table[0] 25#endif 26 27#define HASH_2_SIZE (UINT32_C(1) << 10) 28#define HASH_3_SIZE (UINT32_C(1) << 16) 29#define HASH_4_SIZE (UINT32_C(1) << 20) 30 31#define HASH_2_MASK (HASH_2_SIZE - 1) 32#define HASH_3_MASK (HASH_3_SIZE - 1) 33#define HASH_4_MASK (HASH_4_SIZE - 1) 34 35#define FIX_3_HASH_SIZE (HASH_2_SIZE) 36#define FIX_4_HASH_SIZE (HASH_2_SIZE + HASH_3_SIZE) 37#define FIX_5_HASH_SIZE (HASH_2_SIZE + HASH_3_SIZE + HASH_4_SIZE) 38 39// Endianness doesn't matter in hash_2_calc() (no effect on the output). 40#ifdef TUKLIB_FAST_UNALIGNED_ACCESS 41# define hash_2_calc() \ 42 const uint32_t hash_value = *(const uint16_t *)(cur); 43#else 44# define hash_2_calc() \ 45 const uint32_t hash_value \ 46 = (uint32_t)(cur[0]) | ((uint32_t)(cur[1]) << 8) 47#endif 48 49#define hash_3_calc() \ 50 const uint32_t temp = hash_table[cur[0]] ^ cur[1]; \ 51 const uint32_t hash_2_value = temp & HASH_2_MASK; \ 52 const uint32_t hash_value \ 53 = (temp ^ ((uint32_t)(cur[2]) << 8)) & mf->hash_mask 54 55#define hash_4_calc() \ 56 const uint32_t temp = hash_table[cur[0]] ^ cur[1]; \ 57 const uint32_t hash_2_value = temp & HASH_2_MASK; \ 58 const uint32_t hash_3_value \ 59 = (temp ^ ((uint32_t)(cur[2]) << 8)) & HASH_3_MASK; \ 60 const uint32_t hash_value = (temp ^ ((uint32_t)(cur[2]) << 8) \ 61 ^ (hash_table[cur[3]] << 5)) & mf->hash_mask 62 63 64// The following are not currently used. 65 66#define hash_5_calc() \ 67 const uint32_t temp = hash_table[cur[0]] ^ cur[1]; \ 68 const uint32_t hash_2_value = temp & HASH_2_MASK; \ 69 const uint32_t hash_3_value \ 70 = (temp ^ ((uint32_t)(cur[2]) << 8)) & HASH_3_MASK; \ 71 uint32_t hash_4_value = (temp ^ ((uint32_t)(cur[2]) << 8) ^ \ 72 ^ hash_table[cur[3]] << 5); \ 73 const uint32_t hash_value \ 74 = (hash_4_value ^ (hash_table[cur[4]] << 3)) \ 75 & mf->hash_mask; \ 76 hash_4_value &= HASH_4_MASK 77 78/* 79#define hash_zip_calc() \ 80 const uint32_t hash_value \ 81 = (((uint32_t)(cur[0]) | ((uint32_t)(cur[1]) << 8)) \ 82 ^ hash_table[cur[2]]) & 0xFFFF 83*/ 84 85#define hash_zip_calc() \ 86 const uint32_t hash_value \ 87 = (((uint32_t)(cur[2]) | ((uint32_t)(cur[0]) << 8)) \ 88 ^ hash_table[cur[1]]) & 0xFFFF 89 90#define mt_hash_2_calc() \ 91 const uint32_t hash_2_value \ 92 = (hash_table[cur[0]] ^ cur[1]) & HASH_2_MASK 93 94#define mt_hash_3_calc() \ 95 const uint32_t temp = hash_table[cur[0]] ^ cur[1]; \ 96 const uint32_t hash_2_value = temp & HASH_2_MASK; \ 97 const uint32_t hash_3_value \ 98 = (temp ^ ((uint32_t)(cur[2]) << 8)) & HASH_3_MASK 99 100#define mt_hash_4_calc() \ 101 const uint32_t temp = hash_table[cur[0]] ^ cur[1]; \ 102 const uint32_t hash_2_value = temp & HASH_2_MASK; \ 103 const uint32_t hash_3_value \ 104 = (temp ^ ((uint32_t)(cur[2]) << 8)) & HASH_3_MASK; \ 105 const uint32_t hash_4_value = (temp ^ ((uint32_t)(cur[2]) << 8) ^ \ 106 (hash_table[cur[3]] << 5)) & HASH_4_MASK 107 108#endif 109