Source code
Revision control
Copy as Markdown
Other Tools
/* 7zCrcOpt.c -- CRC32 calculation↩
2017-04-03 : 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↩