1010 * We use a normal (not "reflected", in Williams' terms) CRC, using initial
1111 * all-ones register contents and a final bit inversion.
1212 *
13- * The 64-bit variant is not used as of PostgreSQL 8.1, but we retain the
14- * code for possible future use.
15- *
1613 *
1714 * Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group
1815 * Portions Copyright (c) 1994, Regents of the University of California
@@ -56,97 +53,4 @@ do { \
5653/* Constant table for CRC calculation */
5754extern CRCDLLIMPORT const uint32 pg_crc32_table [];
5855
59-
60- #ifdef PROVIDE_64BIT_CRC
61-
62- /*
63- * If we use a 64-bit integer type, then a 64-bit CRC looks just like the
64- * usual sort of implementation. However, we can also fake it with two
65- * 32-bit registers. Experience has shown that the two-32-bit-registers code
66- * is as fast as, or even much faster than, the 64-bit code on all but true
67- * 64-bit machines. We use SIZEOF_VOID_P to check the native word width.
68- */
69-
70- #if SIZEOF_VOID_P < 8
71-
72- /*
73- * crc0 represents the LSBs of the 64-bit value, crc1 the MSBs. Note that
74- * with crc0 placed first, the output of 32-bit and 64-bit implementations
75- * will be bit-compatible only on little-endian architectures. If it were
76- * important to make the two possible implementations bit-compatible on
77- * all machines, we could do a configure test to decide how to order the
78- * two fields, but it seems not worth the trouble.
79- */
80- typedef struct pg_crc64
81- {
82- uint32 crc0 ;
83- uint32 crc1 ;
84- } pg_crc64 ;
85-
86- /* Initialize a CRC accumulator */
87- #define INIT_CRC64 (crc ) ((crc).crc0 = 0xffffffff, (crc).crc1 = 0xffffffff)
88-
89- /* Finish a CRC calculation */
90- #define FIN_CRC64 (crc ) ((crc).crc0 ^= 0xffffffff, (crc).crc1 ^= 0xffffffff)
91-
92- /* Accumulate some (more) bytes into a CRC */
93- #define COMP_CRC64 (crc , data , len ) \
94- do { \
95- uint32 __crc0 = (crc).crc0; \
96- uint32 __crc1 = (crc).crc1; \
97- unsigned char *__data = (unsigned char *) (data); \
98- uint32 __len = (len); \
99- \
100- while (__len-- > 0) \
101- { \
102- int __tab_index = ((int) (__crc1 >> 24) ^ *__data++) & 0xFF; \
103- __crc1 = pg_crc64_table1[__tab_index] ^ ((__crc1 << 8) | (__crc0 >> 24)); \
104- __crc0 = pg_crc64_table0[__tab_index] ^ (__crc0 << 8); \
105- } \
106- (crc).crc0 = __crc0; \
107- (crc).crc1 = __crc1; \
108- } while (0)
109-
110- /* Check for equality of two CRCs */
111- #define EQ_CRC64 (c1 ,c2 ) ((c1).crc0 == (c2).crc0 && (c1).crc1 == (c2).crc1)
112-
113- /* Constant table for CRC calculation */
114- extern CRCDLLIMPORT const uint32 pg_crc64_table0 [];
115- extern CRCDLLIMPORT const uint32 pg_crc64_table1 [];
116- #else /* use int64 implementation */
117-
118- typedef struct pg_crc64
119- {
120- uint64 crc0 ;
121- } pg_crc64 ;
122-
123- /* Initialize a CRC accumulator */
124- #define INIT_CRC64 (crc ) ((crc).crc0 = UINT64CONST(0xffffffffffffffff))
125-
126- /* Finish a CRC calculation */
127- #define FIN_CRC64 (crc ) ((crc).crc0 ^= UINT64CONST(0xffffffffffffffff))
128-
129- /* Accumulate some (more) bytes into a CRC */
130- #define COMP_CRC64 (crc , data , len ) \
131- do { \
132- uint64 __crc0 = (crc).crc0; \
133- unsigned char *__data = (unsigned char *) (data); \
134- uint32 __len = (len); \
135- \
136- while (__len-- > 0) \
137- { \
138- int __tab_index = ((int) (__crc0 >> 56) ^ *__data++) & 0xFF; \
139- __crc0 = pg_crc64_table[__tab_index] ^ (__crc0 << 8); \
140- } \
141- (crc).crc0 = __crc0; \
142- } while (0)
143-
144- /* Check for equality of two CRCs */
145- #define EQ_CRC64 (c1 ,c2 ) ((c1).crc0 == (c2).crc0)
146-
147- /* Constant table for CRC calculation */
148- extern CRCDLLIMPORT const uint64 pg_crc64_table [];
149- #endif /* SIZEOF_VOID_P < 8 */
150- #endif /* PROVIDE_64BIT_CRC */
151-
15256#endif /* PG_CRC_H */
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