1 /* XzCrc64Opt.c -- CRC64 calculation
2 2021-02-09 : Igor Pavlov : Public domain */
3
4 #include "Precomp.h"
5
6 #include "CpuArch.h"
7
8 #ifndef MY_CPU_BE
9
10 #define CRC64_UPDATE_BYTE_2(crc, b) (table[((crc) ^ (b)) & 0xFF] ^ ((crc) >> 8))
11
12 UInt64 MY_FAST_CALL XzCrc64UpdateT4(UInt64 v, const void *data, size_t size, const UInt64 *table);
XzCrc64UpdateT4(UInt64 v,const void * data,size_t size,const UInt64 * table)13 UInt64 MY_FAST_CALL XzCrc64UpdateT4(UInt64 v, const void *data, size_t size, const UInt64 *table)
14 {
15 const Byte *p = (const Byte *)data;
16 for (; size > 0 && ((unsigned)(ptrdiff_t)p & 3) != 0; size--, p++)
17 v = CRC64_UPDATE_BYTE_2(v, *p);
18 for (; size >= 4; size -= 4, p += 4)
19 {
20 UInt32 d = (UInt32)v ^ *(const UInt32 *)(const void *)p;
21 v = (v >> 32)
22 ^ (table + 0x300)[((d ) & 0xFF)]
23 ^ (table + 0x200)[((d >> 8) & 0xFF)]
24 ^ (table + 0x100)[((d >> 16) & 0xFF)]
25 ^ (table + 0x000)[((d >> 24))];
26 }
27 for (; size > 0; size--, p++)
28 v = CRC64_UPDATE_BYTE_2(v, *p);
29 return v;
30 }
31
32 #endif
33
34
35 #ifndef MY_CPU_LE
36
37 #define CRC_UINT64_SWAP(v) \
38 ((v >> 56) \
39 | ((v >> 40) & ((UInt64)0xFF << 8)) \
40 | ((v >> 24) & ((UInt64)0xFF << 16)) \
41 | ((v >> 8) & ((UInt64)0xFF << 24)) \
42 | ((v << 8) & ((UInt64)0xFF << 32)) \
43 | ((v << 24) & ((UInt64)0xFF << 40)) \
44 | ((v << 40) & ((UInt64)0xFF << 48)) \
45 | ((v << 56)))
46
47 #define CRC64_UPDATE_BYTE_2_BE(crc, b) (table[(Byte)((crc) >> 56) ^ (b)] ^ ((crc) << 8))
48
49 UInt64 MY_FAST_CALL XzCrc64UpdateT1_BeT4(UInt64 v, const void *data, size_t size, const UInt64 *table);
XzCrc64UpdateT1_BeT4(UInt64 v,const void * data,size_t size,const UInt64 * table)50 UInt64 MY_FAST_CALL XzCrc64UpdateT1_BeT4(UInt64 v, const void *data, size_t size, const UInt64 *table)
51 {
52 const Byte *p = (const Byte *)data;
53 table += 0x100;
54 v = CRC_UINT64_SWAP(v);
55 for (; size > 0 && ((unsigned)(ptrdiff_t)p & 3) != 0; size--, p++)
56 v = CRC64_UPDATE_BYTE_2_BE(v, *p);
57 for (; size >= 4; size -= 4, p += 4)
58 {
59 UInt32 d = (UInt32)(v >> 32) ^ *(const UInt32 *)(const void *)p;
60 v = (v << 32)
61 ^ (table + 0x000)[((d ) & 0xFF)]
62 ^ (table + 0x100)[((d >> 8) & 0xFF)]
63 ^ (table + 0x200)[((d >> 16) & 0xFF)]
64 ^ (table + 0x300)[((d >> 24))];
65 }
66 for (; size > 0; size--, p++)
67 v = CRC64_UPDATE_BYTE_2_BE(v, *p);
68 return CRC_UINT64_SWAP(v);
69 }
70
71 #endif
72