Merge pull request #511 from negativeExponent/updates

[pcsx_rearmed.git] / deps / lzma-16.04 / C / XzCrc64.c

/* XzCrc64.c -- CRC64 calculation\r
2015-03-01 : Igor Pavlov : Public domain */\r
\r
#include "Precomp.h"\r
\r
#include "XzCrc64.h"\r
#include "CpuArch.h"\r
\r
#define kCrc64Poly UINT64_CONST(0xC96C5795D7870F42)\r
\r
#ifdef MY_CPU_LE\r
  #define CRC_NUM_TABLES 4\r
#else\r
  #define CRC_NUM_TABLES 5\r
  #define CRC_UINT64_SWAP(v) \\r
      ((v >> 56) \\r
    | ((v >> 40) & ((UInt64)0xFF <<  8)) \\r
    | ((v >> 24) & ((UInt64)0xFF << 16)) \\r
    | ((v >>  8) & ((UInt64)0xFF << 24)) \\r
    | ((v <<  8) & ((UInt64)0xFF << 32)) \\r
    | ((v << 24) & ((UInt64)0xFF << 40)) \\r
    | ((v << 40) & ((UInt64)0xFF << 48)) \\r
    | ((v << 56)))\r
\r
  UInt64 MY_FAST_CALL XzCrc64UpdateT1_BeT4(UInt64 v, const void *data, size_t size, const UInt64 *table);\r
#endif\r
\r
#ifndef MY_CPU_BE\r
  UInt64 MY_FAST_CALL XzCrc64UpdateT4(UInt64 v, const void *data, size_t size, const UInt64 *table);\r
#endif\r
\r
typedef UInt64 (MY_FAST_CALL *CRC_FUNC)(UInt64 v, const void *data, size_t size, const UInt64 *table);\r
\r
static CRC_FUNC g_Crc64Update;\r
UInt64 g_Crc64Table[256 * CRC_NUM_TABLES];\r
\r
UInt64 MY_FAST_CALL Crc64Update(UInt64 v, const void *data, size_t size)\r
{\r
  return g_Crc64Update(v, data, size, g_Crc64Table);\r
}\r
\r
UInt64 MY_FAST_CALL Crc64Calc(const void *data, size_t size)\r
{\r
  return g_Crc64Update(CRC64_INIT_VAL, data, size, g_Crc64Table) ^ CRC64_INIT_VAL;\r
}\r
\r
void MY_FAST_CALL Crc64GenerateTable()\r
{\r
  UInt32 i;\r
  for (i = 0; i < 256; i++)\r
  {\r
    UInt64 r = i;\r
    unsigned j;\r
    for (j = 0; j < 8; j++)\r
      r = (r >> 1) ^ (kCrc64Poly & ~((r & 1) - 1));\r
    g_Crc64Table[i] = r;\r
  }\r
  for (; i < 256 * CRC_NUM_TABLES; i++)\r
  {\r
    UInt64 r = g_Crc64Table[i - 256];\r
    g_Crc64Table[i] = g_Crc64Table[r & 0xFF] ^ (r >> 8);\r
  }\r
  \r
  #ifdef MY_CPU_LE\r
\r
  g_Crc64Update = XzCrc64UpdateT4;\r
\r
  #else\r
  {\r
    #ifndef MY_CPU_BE\r
    UInt32 k = 1;\r
    if (*(const Byte *)&k == 1)\r
      g_Crc64Update = XzCrc64UpdateT4;\r
    else\r
    #endif\r
    {\r
      for (i = 256 * CRC_NUM_TABLES - 1; i >= 256; i--)\r
      {\r
        UInt64 x = g_Crc64Table[i - 256];\r
        g_Crc64Table[i] = CRC_UINT64_SWAP(x);\r
      }\r
      g_Crc64Update = XzCrc64UpdateT1_BeT4;\r
    }\r
  }\r
  #endif\r
}\r