lib/lz4/lz4defs.h

   1 /*
   2  * lz4defs.h -- architecture specific defines
   3  *
   4  * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 /*
  12  * Detects 64 bits mode
  13  */
  14 #if defined(CONFIG_64BIT)
  15 #define LZ4_ARCH64 1
  16 #else
  17 #define LZ4_ARCH64 0
  18 #endif
  19
  20 /*
  21  * Architecture-specific macros
  22  */
  23 #define BYTE    u8
  24 typedef struct _U16_S { u16 v; } U16_S;
  25 typedef struct _U32_S { u32 v; } U32_S;
  26 typedef struct _U64_S { u64 v; } U64_S;
  27 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
  28
  29 #define A16(x) (((U16_S *)(x))->v)
  30 #define A32(x) (((U32_S *)(x))->v)
  31 #define A64(x) (((U64_S *)(x))->v)
  32
  33 #define PUT4(s, d) (A32(d) = A32(s))
  34 #define PUT8(s, d) (A64(d) = A64(s))
  35
  36 #define LZ4_READ_LITTLEENDIAN_16(d, s, p)       \
  37         (d = s - A16(p))
  38
  39 #define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
  40         do {    \
  41                 A16(p) = v; \
  42                 p += 2; \
  43         } while (0)
  44 #else /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
  45
  46 #define A64(x) get_unaligned((u64 *)&(((U16_S *)(x))->v))
  47 #define A32(x) get_unaligned((u32 *)&(((U16_S *)(x))->v))
  48 #define A16(x) get_unaligned((u16 *)&(((U16_S *)(x))->v))
  49
  50 #define PUT4(s, d) \
  51         put_unaligned(get_unaligned((const u32 *) s), (u32 *) d)
  52 #define PUT8(s, d) \
  53         put_unaligned(get_unaligned((const u64 *) s), (u64 *) d)
  54
  55 #define LZ4_READ_LITTLEENDIAN_16(d, s, p)       \
  56         (d = s - get_unaligned_le16(p))
  57
  58 #define LZ4_WRITE_LITTLEENDIAN_16(p, v)                 \
  59         do {                                            \
  60                 put_unaligned_le16(v, (u16 *)(p));      \
  61                 p += 2;                                 \
  62         } while (0)
  63 #endif
  64
  65 #define COPYLENGTH 8
  66 #define ML_BITS  4
  67 #define ML_MASK  ((1U << ML_BITS) - 1)
  68 #define RUN_BITS (8 - ML_BITS)
  69 #define RUN_MASK ((1U << RUN_BITS) - 1)
  70 #define MEMORY_USAGE    14
  71 #define MINMATCH        4
  72 #define SKIPSTRENGTH    6
  73 #define LASTLITERALS    5
  74 #define MFLIMIT         (COPYLENGTH + MINMATCH)
  75 #define MINLENGTH       (MFLIMIT + 1)
  76 #define MAXD_LOG        16
  77 #define MAXD            (1 << MAXD_LOG)
  78 #define MAXD_MASK       (u32)(MAXD - 1)
  79 #define MAX_DISTANCE    (MAXD - 1)
  80 #define HASH_LOG        (MAXD_LOG - 1)
  81 #define HASHTABLESIZE   (1 << HASH_LOG)
  82 #define MAX_NB_ATTEMPTS 256
  83 #define OPTIMAL_ML      (int)((ML_MASK-1)+MINMATCH)
  84 #define LZ4_64KLIMIT    ((1<<16) + (MFLIMIT - 1))
  85 #define HASHLOG64K      ((MEMORY_USAGE - 2) + 1)
  86 #define HASH64KTABLESIZE        (1U << HASHLOG64K)
  87 #define LZ4_HASH_VALUE(p)       (((A32(p)) * 2654435761U) >> \
  88                                 ((MINMATCH * 8) - (MEMORY_USAGE-2)))
  89 #define LZ4_HASH64K_VALUE(p)    (((A32(p)) * 2654435761U) >> \
  90                                 ((MINMATCH * 8) - HASHLOG64K))
  91 #define HASH_VALUE(p)           (((A32(p)) * 2654435761U) >> \
  92                                 ((MINMATCH * 8) - HASH_LOG))
  93
  94 #if LZ4_ARCH64/* 64-bit */
  95 #define STEPSIZE 8
  96
  97 #define LZ4_COPYSTEP(s, d)      \
  98         do {                    \
  99                 PUT8(s, d);     \
 100                 d += 8;         \
 101                 s += 8;         \
 102         } while (0)
 103
 104 #define LZ4_COPYPACKET(s, d)    LZ4_COPYSTEP(s, d)
 105
 106 #define LZ4_SECURECOPY(s, d, e)                 \
 107         do {                                    \
 108                 if (d < e) {                    \
 109                         LZ4_WILDCOPY(s, d, e);  \
 110                 }                               \
 111         } while (0)
 112 #define HTYPE u32
 113
 114 #ifdef __BIG_ENDIAN
 115 #define LZ4_NBCOMMONBYTES(val) (__builtin_clzll(val) >> 3)
 116 #else
 117 #define LZ4_NBCOMMONBYTES(val) (__builtin_ctzll(val) >> 3)
 118 #endif
 119
 120 #else   /* 32-bit */
 121 #define STEPSIZE 4
 122
 123 #define LZ4_COPYSTEP(s, d)      \
 124         do {                    \
 125                 PUT4(s, d);     \
 126                 d += 4;         \
 127                 s += 4;         \
 128         } while (0)
 129
 130 #define LZ4_COPYPACKET(s, d)            \
 131         do {                            \
 132                 LZ4_COPYSTEP(s, d);     \
 133                 LZ4_COPYSTEP(s, d);     \
 134         } while (0)
 135
 136 #define LZ4_SECURECOPY  LZ4_WILDCOPY
 137 #define HTYPE const u8*
 138
 139 #ifdef __BIG_ENDIAN
 140 #define LZ4_NBCOMMONBYTES(val) (__builtin_clz(val) >> 3)
 141 #else
 142 #define LZ4_NBCOMMONBYTES(val) (__builtin_ctz(val) >> 3)
 143 #endif
 144
 145 #endif
 146
 147 #define LZ4_WILDCOPY(s, d, e)           \
 148         do {                            \
 149                 LZ4_COPYPACKET(s, d);   \
 150         } while (d < e)
 151
 152 #define LZ4_BLINDCOPY(s, d, l)  \
 153         do {    \
 154                 u8 *e = (d) + l;        \
 155                 LZ4_WILDCOPY(s, d, e);  \
 156                 d = e;  \
 157         } while (0)