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/* Normally compiler builtins are used, but sometimes the compiler calls out
of line code. Based on asm-i386/string.h.
*/
#define _STRING_C
#include <linux/string.h>
#include <linux/module.h>
#undef memmove
void *memmove(void *dest, const void *src, size_t count)
{
unsigned long d0, d1, d2, d3;
if (dest < src) {
if ((dest + count) < src)
return memcpy(dest, src, count);
else
__asm__ __volatile__(
"movq %0, %3\n\t"
"shr $3, %0\n\t"
"andq $7, %3\n\t"
"rep\n\t"
"movsq\n\t"
"movq %3, %0\n\t"
"rep\n\t"
"movsb"
: "=&c" (d0), "=&S" (d1), "=&D" (d2), "=r" (d3)
:"0" (count),
"1" (src),
"2" (dest)
:"memory");
} else {
if((src + count) < dest)
return memcpy(dest, src, count);
else
__asm__ __volatile__(
"movq %0, %3\n\t"
"lea -8(%1, %0), %1\n\t"
"lea -8(%2, %0), %2\n\t"
"shr $3, %0\n\t"
"andq $7, %3\n\t"
"std\n\t"
"rep\n\t"
"movsq\n\t"
"lea 7(%1), %1\n\t"
"lea 7(%2), %2\n\t"
"movq %3, %0\n\t"
"rep\n\t"
"movsb\n\t"
"cld"
: "=&c" (d0), "=&S" (d1), "=&D" (d2), "=r" (d3)
:"0" (count),
"1" (src),
"2" (dest)
:"memory");
}
return dest;
}
EXPORT_SYMBOL(memmove);
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