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