ce188d4d |
1 | /* XzCrc64.c -- CRC64 calculation\r |
2 | 2015-03-01 : Igor Pavlov : Public domain */\r |
3 | \r |
4 | #include "Precomp.h"\r |
5 | \r |
6 | #include "XzCrc64.h"\r |
7 | #include "CpuArch.h"\r |
8 | \r |
9 | #define kCrc64Poly UINT64_CONST(0xC96C5795D7870F42)\r |
10 | \r |
11 | #ifdef MY_CPU_LE\r |
12 | #define CRC_NUM_TABLES 4\r |
13 | #else\r |
14 | #define CRC_NUM_TABLES 5\r |
15 | #define CRC_UINT64_SWAP(v) \\r |
16 | ((v >> 56) \\r |
17 | | ((v >> 40) & ((UInt64)0xFF << 8)) \\r |
18 | | ((v >> 24) & ((UInt64)0xFF << 16)) \\r |
19 | | ((v >> 8) & ((UInt64)0xFF << 24)) \\r |
20 | | ((v << 8) & ((UInt64)0xFF << 32)) \\r |
21 | | ((v << 24) & ((UInt64)0xFF << 40)) \\r |
22 | | ((v << 40) & ((UInt64)0xFF << 48)) \\r |
23 | | ((v << 56)))\r |
24 | \r |
25 | UInt64 MY_FAST_CALL XzCrc64UpdateT1_BeT4(UInt64 v, const void *data, size_t size, const UInt64 *table);\r |
26 | #endif\r |
27 | \r |
28 | #ifndef MY_CPU_BE\r |
29 | UInt64 MY_FAST_CALL XzCrc64UpdateT4(UInt64 v, const void *data, size_t size, const UInt64 *table);\r |
30 | #endif\r |
31 | \r |
32 | typedef UInt64 (MY_FAST_CALL *CRC_FUNC)(UInt64 v, const void *data, size_t size, const UInt64 *table);\r |
33 | \r |
34 | static CRC_FUNC g_Crc64Update;\r |
35 | UInt64 g_Crc64Table[256 * CRC_NUM_TABLES];\r |
36 | \r |
37 | UInt64 MY_FAST_CALL Crc64Update(UInt64 v, const void *data, size_t size)\r |
38 | {\r |
39 | return g_Crc64Update(v, data, size, g_Crc64Table);\r |
40 | }\r |
41 | \r |
42 | UInt64 MY_FAST_CALL Crc64Calc(const void *data, size_t size)\r |
43 | {\r |
44 | return g_Crc64Update(CRC64_INIT_VAL, data, size, g_Crc64Table) ^ CRC64_INIT_VAL;\r |
45 | }\r |
46 | \r |
47 | void MY_FAST_CALL Crc64GenerateTable()\r |
48 | {\r |
49 | UInt32 i;\r |
50 | for (i = 0; i < 256; i++)\r |
51 | {\r |
52 | UInt64 r = i;\r |
53 | unsigned j;\r |
54 | for (j = 0; j < 8; j++)\r |
55 | r = (r >> 1) ^ (kCrc64Poly & ~((r & 1) - 1));\r |
56 | g_Crc64Table[i] = r;\r |
57 | }\r |
58 | for (; i < 256 * CRC_NUM_TABLES; i++)\r |
59 | {\r |
60 | UInt64 r = g_Crc64Table[i - 256];\r |
61 | g_Crc64Table[i] = g_Crc64Table[r & 0xFF] ^ (r >> 8);\r |
62 | }\r |
63 | \r |
64 | #ifdef MY_CPU_LE\r |
65 | \r |
66 | g_Crc64Update = XzCrc64UpdateT4;\r |
67 | \r |
68 | #else\r |
69 | {\r |
70 | #ifndef MY_CPU_BE\r |
71 | UInt32 k = 1;\r |
72 | if (*(const Byte *)&k == 1)\r |
73 | g_Crc64Update = XzCrc64UpdateT4;\r |
74 | else\r |
75 | #endif\r |
76 | {\r |
77 | for (i = 256 * CRC_NUM_TABLES - 1; i >= 256; i--)\r |
78 | {\r |
79 | UInt64 x = g_Crc64Table[i - 256];\r |
80 | g_Crc64Table[i] = CRC_UINT64_SWAP(x);\r |
81 | }\r |
82 | g_Crc64Update = XzCrc64UpdateT1_BeT4;\r |
83 | }\r |
84 | }\r |
85 | #endif\r |
86 | }\r |