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1 #include <string.h>
2 #include <stdint.h>
3 #include <endian.h>
4 
5 #ifdef LOSCFG_KERNEL_LMS
__memcpy(void * restrict dest,const void * restrict src,size_t n)6 __attribute__((no_sanitize_address)) void *__memcpy(void *restrict dest, const void *restrict src, size_t n)
7 #else
8 void *memcpy(void *restrict dest, const void *restrict src, size_t n)
9 #endif
10 {
11 	unsigned char *d = dest;
12 	const unsigned char *s = src;
13 
14 #ifdef __GNUC__
15 
16 #if __BYTE_ORDER == __LITTLE_ENDIAN
17 #define LS >>
18 #define RS <<
19 #else
20 #define LS <<
21 #define RS >>
22 #endif
23 
24 	typedef uint32_t __attribute__((__may_alias__)) u32;
25 	uint32_t w, x;
26 
27 	for (; (uintptr_t)s % 4 && n; n--) *d++ = *s++;
28 
29 	if ((uintptr_t)d % 4 == 0) {
30 		for (; n>=16; s+=16, d+=16, n-=16) {
31 			*(u32 *)(d+0) = *(u32 *)(s+0);
32 			*(u32 *)(d+4) = *(u32 *)(s+4);
33 			*(u32 *)(d+8) = *(u32 *)(s+8);
34 			*(u32 *)(d+12) = *(u32 *)(s+12);
35 		}
36 		if (n&8) {
37 			*(u32 *)(d+0) = *(u32 *)(s+0);
38 			*(u32 *)(d+4) = *(u32 *)(s+4);
39 			d += 8; s += 8;
40 		}
41 		if (n&4) {
42 			*(u32 *)(d+0) = *(u32 *)(s+0);
43 			d += 4; s += 4;
44 		}
45 		if (n&2) {
46 			*d++ = *s++; *d++ = *s++;
47 		}
48 		if (n&1) {
49 			*d = *s;
50 		}
51 		return dest;
52 	}
53 
54 	if (n >= 32) switch ((uintptr_t)d % 4) {
55 	case 1:
56 		w = *(u32 *)s;
57 		*d++ = *s++;
58 		*d++ = *s++;
59 		*d++ = *s++;
60 		n -= 3;
61 		for (; n>=17; s+=16, d+=16, n-=16) {
62 			x = *(u32 *)(s+1);
63 			*(u32 *)(d+0) = (w LS 24) | (x RS 8);
64 			w = *(u32 *)(s+5);
65 			*(u32 *)(d+4) = (x LS 24) | (w RS 8);
66 			x = *(u32 *)(s+9);
67 			*(u32 *)(d+8) = (w LS 24) | (x RS 8);
68 			w = *(u32 *)(s+13);
69 			*(u32 *)(d+12) = (x LS 24) | (w RS 8);
70 		}
71 		break;
72 	case 2:
73 		w = *(u32 *)s;
74 		*d++ = *s++;
75 		*d++ = *s++;
76 		n -= 2;
77 		for (; n>=18; s+=16, d+=16, n-=16) {
78 			x = *(u32 *)(s+2);
79 			*(u32 *)(d+0) = (w LS 16) | (x RS 16);
80 			w = *(u32 *)(s+6);
81 			*(u32 *)(d+4) = (x LS 16) | (w RS 16);
82 			x = *(u32 *)(s+10);
83 			*(u32 *)(d+8) = (w LS 16) | (x RS 16);
84 			w = *(u32 *)(s+14);
85 			*(u32 *)(d+12) = (x LS 16) | (w RS 16);
86 		}
87 		break;
88 	case 3:
89 		w = *(u32 *)s;
90 		*d++ = *s++;
91 		n -= 1;
92 		for (; n>=19; s+=16, d+=16, n-=16) {
93 			x = *(u32 *)(s+3);
94 			*(u32 *)(d+0) = (w LS 8) | (x RS 24);
95 			w = *(u32 *)(s+7);
96 			*(u32 *)(d+4) = (x LS 8) | (w RS 24);
97 			x = *(u32 *)(s+11);
98 			*(u32 *)(d+8) = (w LS 8) | (x RS 24);
99 			w = *(u32 *)(s+15);
100 			*(u32 *)(d+12) = (x LS 8) | (w RS 24);
101 		}
102 		break;
103 	}
104 	if (n&16) {
105 		*d++ = *s++; *d++ = *s++; *d++ = *s++; *d++ = *s++;
106 		*d++ = *s++; *d++ = *s++; *d++ = *s++; *d++ = *s++;
107 		*d++ = *s++; *d++ = *s++; *d++ = *s++; *d++ = *s++;
108 		*d++ = *s++; *d++ = *s++; *d++ = *s++; *d++ = *s++;
109 	}
110 	if (n&8) {
111 		*d++ = *s++; *d++ = *s++; *d++ = *s++; *d++ = *s++;
112 		*d++ = *s++; *d++ = *s++; *d++ = *s++; *d++ = *s++;
113 	}
114 	if (n&4) {
115 		*d++ = *s++; *d++ = *s++; *d++ = *s++; *d++ = *s++;
116 	}
117 	if (n&2) {
118 		*d++ = *s++; *d++ = *s++;
119 	}
120 	if (n&1) {
121 		*d = *s;
122 	}
123 	return dest;
124 #endif
125 
126 	for (; n; n--) *d++ = *s++;
127 	return dest;
128 }
129