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comparison crc32i.h @ 0:422835bc1aca

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*: checkin
author Paper <paper@tflc.us>
date Mon, 09 Feb 2026 01:15:00 -0500
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children 90cb48b87dcc
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-1:000000000000 0:422835bc1aca
1 /* internal crc32 definitions */
2
3 #include "crc32.h"
4
5 #define CRC32_API __attribute__((__visibility__("default")))
6
7 /* all LUTs etc. are generated at compile time.
8 * eventually, I'd like to have all internal info
9 * stored in one opaque pointer. this pointer will
10 * contain the LUTs (or maybe a pointer to one).
11 * We could also create these structures at compile
12 * time and have a flag that says whether it needs
13 * to be destroyed or if it can be cached. */
14 #define CRC32_POLYNOMIAL 0xedb88320
15
16 /* crc32b.c */
17 #ifdef __GNUC__
18 # define CRC32_PURE __attribute__((__pure__))
19 #else
20 # define CRC32_PURE
21 #endif
22
23 #define ALIGNOF(type) offsetof(struct { type a; char b; }, b)
24 #define ALIGNED(ptr, alignment) (((uintptr_t)(ptr) % (alignment)) == 0)
25 #define ALIGNED_TYPE(ptr, type) ALIGNED(ptr, ALIGNOF(type))
26
27 typedef uint32_t (*crc32_r_spec)(uint32_t, const unsigned char *, size_t);
28
29 /* shared by crc32c and crc32qw */
30 extern const uint32_t crc32_tab[256];
31
32 /* Calculates crc32 by bytes. Has no alignment requirement */
33 uint32_t crc32c_r(uint32_t crc, const unsigned char *message, size_t sz);
34 /* Calculates crc32 in dwords. Requires 4-byte alignment */
35 uint32_t crc32qw_r(uint32_t crc, const unsigned char *message, size_t sz);
36 /* Calculates crc32 using intel SIMD. Requires 16-byte alignment */
37 uint32_t crc32x86_vpclmulqdq_r(uint32_t crc, const unsigned char *msg, size_t sz);
38
39 /* Maximum alignment value for each impl to work */
40 #define MAX(x, y) ((x)>(y)?(x):(y))
41 #define MIN(x, y) ((x)<(y)?(x):(y))
42 #define CRC32_MAX_ALIGNMENT MAX(16, ALIGNOF(uint32_t))
43
44 #define ARRAY_SIZE(x) (sizeof(x)/sizeof((x)[0]))
45