| /* 7zCrcOpt.c -- CRC32 calculation |
| 2015-03-01 : Igor Pavlov : Public domain */ |
| |
| #include "Precomp.h" |
| |
| #include "CpuArch.h" |
| |
| #ifndef MY_CPU_BE |
| |
| #define CRC_UPDATE_BYTE_2(crc, b) (table[((crc) ^ (b)) & 0xFF] ^ ((crc) >> 8)) |
| |
| UInt32 MY_FAST_CALL CrcUpdateT4(UInt32 v, const void *data, size_t size, const UInt32 *table) |
| { |
| const Byte *p = (const Byte *)data; |
| for (; size > 0 && ((unsigned)(ptrdiff_t)p & 3) != 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2(v, *p); |
| for (; size >= 4; size -= 4, p += 4) |
| { |
| v ^= *(const UInt32 *)p; |
| v = |
| table[0x300 + ((v ) & 0xFF)] |
| ^ table[0x200 + ((v >> 8) & 0xFF)] |
| ^ table[0x100 + ((v >> 16) & 0xFF)] |
| ^ table[0x000 + ((v >> 24))]; |
| } |
| for (; size > 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2(v, *p); |
| return v; |
| } |
| |
| UInt32 MY_FAST_CALL CrcUpdateT8(UInt32 v, const void *data, size_t size, const UInt32 *table) |
| { |
| const Byte *p = (const Byte *)data; |
| for (; size > 0 && ((unsigned)(ptrdiff_t)p & 7) != 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2(v, *p); |
| for (; size >= 8; size -= 8, p += 8) |
| { |
| UInt32 d; |
| v ^= *(const UInt32 *)p; |
| v = |
| table[0x700 + ((v ) & 0xFF)] |
| ^ table[0x600 + ((v >> 8) & 0xFF)] |
| ^ table[0x500 + ((v >> 16) & 0xFF)] |
| ^ table[0x400 + ((v >> 24))]; |
| d = *((const UInt32 *)p + 1); |
| v ^= |
| table[0x300 + ((d ) & 0xFF)] |
| ^ table[0x200 + ((d >> 8) & 0xFF)] |
| ^ table[0x100 + ((d >> 16) & 0xFF)] |
| ^ table[0x000 + ((d >> 24))]; |
| } |
| for (; size > 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2(v, *p); |
| return v; |
| } |
| |
| #endif |
| |
| |
| #ifndef MY_CPU_LE |
| |
| #define CRC_UINT32_SWAP(v) ((v >> 24) | ((v >> 8) & 0xFF00) | ((v << 8) & 0xFF0000) | (v << 24)) |
| |
| #define CRC_UPDATE_BYTE_2_BE(crc, b) (table[(((crc) >> 24) ^ (b))] ^ ((crc) << 8)) |
| |
| UInt32 MY_FAST_CALL CrcUpdateT1_BeT4(UInt32 v, const void *data, size_t size, const UInt32 *table) |
| { |
| const Byte *p = (const Byte *)data; |
| table += 0x100; |
| v = CRC_UINT32_SWAP(v); |
| for (; size > 0 && ((unsigned)(ptrdiff_t)p & 3) != 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2_BE(v, *p); |
| for (; size >= 4; size -= 4, p += 4) |
| { |
| v ^= *(const UInt32 *)p; |
| v = |
| table[0x000 + ((v ) & 0xFF)] |
| ^ table[0x100 + ((v >> 8) & 0xFF)] |
| ^ table[0x200 + ((v >> 16) & 0xFF)] |
| ^ table[0x300 + ((v >> 24))]; |
| } |
| for (; size > 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2_BE(v, *p); |
| return CRC_UINT32_SWAP(v); |
| } |
| |
| UInt32 MY_FAST_CALL CrcUpdateT1_BeT8(UInt32 v, const void *data, size_t size, const UInt32 *table) |
| { |
| const Byte *p = (const Byte *)data; |
| table += 0x100; |
| v = CRC_UINT32_SWAP(v); |
| for (; size > 0 && ((unsigned)(ptrdiff_t)p & 7) != 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2_BE(v, *p); |
| for (; size >= 8; size -= 8, p += 8) |
| { |
| UInt32 d; |
| v ^= *(const UInt32 *)p; |
| v = |
| table[0x400 + ((v ) & 0xFF)] |
| ^ table[0x500 + ((v >> 8) & 0xFF)] |
| ^ table[0x600 + ((v >> 16) & 0xFF)] |
| ^ table[0x700 + ((v >> 24))]; |
| d = *((const UInt32 *)p + 1); |
| v ^= |
| table[0x000 + ((d ) & 0xFF)] |
| ^ table[0x100 + ((d >> 8) & 0xFF)] |
| ^ table[0x200 + ((d >> 16) & 0xFF)] |
| ^ table[0x300 + ((d >> 24))]; |
| } |
| for (; size > 0; size--, p++) |
| v = CRC_UPDATE_BYTE_2_BE(v, *p); |
| return CRC_UINT32_SWAP(v); |
| } |
| |
| #endif |