tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#include "misc.h"
2#include "../string.c"
3
4/* misc.h might pull in string_32.h which has a macro for memcpy. undef that */
5#undef memcpy
6
7#ifdef CONFIG_X86_32
8void *memcpy(void *dest, const void *src, size_t n)
9{
10 int d0, d1, d2;
11 asm volatile(
12 "rep ; movsl\n\t"
13 "movl %4,%%ecx\n\t"
14 "rep ; movsb\n\t"
15 : "=&c" (d0), "=&D" (d1), "=&S" (d2)
16 : "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
17 : "memory");
18
19 return dest;
20}
21#else
22void *memcpy(void *dest, const void *src, size_t n)
23{
24 long d0, d1, d2;
25 asm volatile(
26 "rep ; movsq\n\t"
27 "movq %4,%%rcx\n\t"
28 "rep ; movsb\n\t"
29 : "=&c" (d0), "=&D" (d1), "=&S" (d2)
30 : "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
31 : "memory");
32
33 return dest;
34}
35#endif
36
37void *memset(void *s, int c, size_t n)
38{
39 int i;
40 char *ss = s;
41
42 for (i = 0; i < n; i++)
43 ss[i] = c;
44 return s;
45}