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pg_crc32c_loongarch.c
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1/*-------------------------------------------------------------------------
2 *
3 * pg_crc32c_loongarch.c
4 * Compute CRC-32C checksum using LoongArch CRCC instructions
5 *
6 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 * Portions Copyright (c) 1994, Regents of the University of California
8 *
9 *
10 * IDENTIFICATION
11 * src/port/pg_crc32c_loongarch.c
12 *
13 *-------------------------------------------------------------------------
14 */
15#include "c.h"
16
17#include "port/pg_crc32c.h"
18
21{
22 const unsigned char *p = data;
23 const unsigned char *pend = p + len;
24
25 /*
26 * LoongArch doesn't require alignment, but aligned memory access is
27 * significantly faster. Process leading bytes so that the loop below
28 * starts with a pointer aligned to eight bytes.
29 */
30 if (!PointerIsAligned(p, uint16) &&
31 p + 1 <= pend)
32 {
33 crc = __builtin_loongarch_crcc_w_b_w(*p, crc);
34 p += 1;
35 }
36 if (!PointerIsAligned(p, uint32) &&
37 p + 2 <= pend)
38 {
39 crc = __builtin_loongarch_crcc_w_h_w(*(uint16 *) p, crc);
40 p += 2;
41 }
42 if (!PointerIsAligned(p, uint64) &&
43 p + 4 <= pend)
44 {
45 crc = __builtin_loongarch_crcc_w_w_w(*(uint32 *) p, crc);
46 p += 4;
47 }
48
49 /* Process eight bytes at a time, as far as we can. */
50 while (p + 8 <= pend)
51 {
52 crc = __builtin_loongarch_crcc_w_d_w(*(uint64 *) p, crc);
53 p += 8;
54 }
55
56 /* Process remaining 0-7 bytes. */
57 if (p + 4 <= pend)
58 {
59 crc = __builtin_loongarch_crcc_w_w_w(*(uint32 *) p, crc);
60 p += 4;
61 }
62 if (p + 2 <= pend)
63 {
64 crc = __builtin_loongarch_crcc_w_h_w(*(uint16 *) p, crc);
65 p += 2;
66 }
67 if (p < pend)
68 {
69 crc = __builtin_loongarch_crcc_w_b_w(*p, crc);
70 }
71
72 return crc;
73}
#define PointerIsAligned(pointer, type)
Definition: c.h:726
uint64_t uint64
Definition: c.h:489
uint16_t uint16
Definition: c.h:487
uint32_t uint32
Definition: c.h:488
uint32 pg_crc32c
Definition: pg_crc32c.h:38
pg_crc32c pg_comp_crc32c_loongarch(pg_crc32c crc, const void *data, size_t len)
const void size_t len
const void * data
return crc
const unsigned char * pend