diff options
Diffstat (limited to 'arch/x86/boot/compressed/string.c')
| -rw-r--r-- | arch/x86/boot/compressed/string.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c index 212004ec787d..3b5a82fc6ad7 100644 --- a/arch/x86/boot/compressed/string.c +++ b/arch/x86/boot/compressed/string.c @@ -11,3 +11,36 @@ int memcmp(const void *s1, const void *s2, size_t len) } #include "../string.c" + +/* misc.h might pull in string_32.h which has a macro for memcpy. undef that */ +#undef memcpy + +#ifdef CONFIG_X86_32 +void *memcpy(void *dest, const void *src, size_t n) +{ + int d0, d1, d2; + asm volatile( + "rep ; movsl\n\t" + "movl %4,%%ecx\n\t" + "rep ; movsb\n\t" + : "=&c" (d0), "=&D" (d1), "=&S" (d2) + : "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src) + : "memory"); + + return dest; +} +#else +void *memcpy(void *dest, const void *src, size_t n) +{ + long d0, d1, d2; + asm volatile( + "rep ; movsq\n\t" + "movq %4,%%rcx\n\t" + "rep ; movsb\n\t" + : "=&c" (d0), "=&D" (d1), "=&S" (d2) + : "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src) + : "memory"); + + return dest; +} +#endif |