1
2
3
4
5
6
7#include <linux/module.h>
8#include <linux/string.h>
9
10void *memcpy(void *to, const void *from, size_t n)
11{
12 void *xto = to;
13 size_t temp;
14
15 if (!n)
16 return xto;
17 if ((long)to & 1) {
18 char *cto = to;
19 const char *cfrom = from;
20 *cto++ = *cfrom++;
21 to = cto;
22 from = cfrom;
23 n--;
24 }
25#if defined(CONFIG_M68000)
26 if ((long)from & 1) {
27 char *cto = to;
28 const char *cfrom = from;
29 for (; n; n--)
30 *cto++ = *cfrom++;
31 return xto;
32 }
33#endif
34 if (n > 2 && (long)to & 2) {
35 short *sto = to;
36 const short *sfrom = from;
37 *sto++ = *sfrom++;
38 to = sto;
39 from = sfrom;
40 n -= 2;
41 }
42 temp = n >> 2;
43 if (temp) {
44 long *lto = to;
45 const long *lfrom = from;
46#if defined(CONFIG_M68000) || defined(CONFIG_COLDFIRE)
47 for (; temp; temp--)
48 *lto++ = *lfrom++;
49#else
50 size_t temp1;
51 asm volatile (
52 " movel %2,%3\n"
53 " andw #7,%3\n"
54 " lsrl #3,%2\n"
55 " negw %3\n"
56 " jmp %%pc@(1f,%3:w:2)\n"
57 "4: movel %0@+,%1@+\n"
58 " movel %0@+,%1@+\n"
59 " movel %0@+,%1@+\n"
60 " movel %0@+,%1@+\n"
61 " movel %0@+,%1@+\n"
62 " movel %0@+,%1@+\n"
63 " movel %0@+,%1@+\n"
64 " movel %0@+,%1@+\n"
65 "1: dbra %2,4b\n"
66 " clrw %2\n"
67 " subql #1,%2\n"
68 " jpl 4b"
69 : "=a" (lfrom), "=a" (lto), "=d" (temp), "=&d" (temp1)
70 : "0" (lfrom), "1" (lto), "2" (temp));
71#endif
72 to = lto;
73 from = lfrom;
74 }
75 if (n & 2) {
76 short *sto = to;
77 const short *sfrom = from;
78 *sto++ = *sfrom++;
79 to = sto;
80 from = sfrom;
81 }
82 if (n & 1) {
83 char *cto = to;
84 const char *cfrom = from;
85 *cto = *cfrom;
86 }
87 return xto;
88}
89EXPORT_SYMBOL(memcpy);
90
