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Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/lib/memcpy_32.c38
-rw-r--r--arch/x86/lib/memmove_64.c46
2 files changed, 68 insertions, 16 deletions
diff --git a/arch/x86/lib/memcpy_32.c b/arch/x86/lib/memcpy_32.c
index 5415a9d..be424df 100644
--- a/arch/x86/lib/memcpy_32.c
+++ b/arch/x86/lib/memcpy_32.c
@@ -25,19 +25,35 @@ void *memmove(void *dest, const void *src, size_t n)
int d0, d1, d2;
if (dest < src) {
- memcpy(dest, src, n);
+ if ((dest + n) < src)
+ return memcpy(dest, src, n);
+ else
+ __asm__ __volatile__(
+ "rep\n\t"
+ "movsb\n\t"
+ : "=&c" (d0), "=&S" (d1), "=&D" (d2)
+ :"0" (n),
+ "1" (src),
+ "2" (dest)
+ :"memory");
+
} else {
- __asm__ __volatile__(
- "std\n\t"
- "rep\n\t"
- "movsb\n\t"
- "cld"
- : "=&c" (d0), "=&S" (d1), "=&D" (d2)
- :"0" (n),
- "1" (n-1+src),
- "2" (n-1+dest)
- :"memory");
+
+ if((src + count) < dest)
+ return memcpy(dest, src, count);
+ else
+ __asm__ __volatile__(
+ "std\n\t"
+ "rep\n\t"
+ "movsb\n\t"
+ "cld"
+ : "=&c" (d0), "=&S" (d1), "=&D" (d2)
+ :"0" (n),
+ "1" (n-1+src),
+ "2" (n-1+dest)
+ :"memory");
}
+
return dest;
}
EXPORT_SYMBOL(memmove);
diff --git a/arch/x86/lib/memmove_64.c b/arch/x86/lib/memmove_64.c
index 0a33909..ecacc4b 100644
--- a/arch/x86/lib/memmove_64.c
+++ b/arch/x86/lib/memmove_64.c
@@ -8,13 +8,49 @@
#undef memmove
void *memmove(void *dest, const void *src, size_t count)
{
+ unsigned long d0, d1, d2, d3;
if (dest < src) {
- return memcpy(dest, src, count);
+ 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 {
- char *p = dest + count;
- const char *s = src + count;
- while (count--)
- *--p = *--s;
+ 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;
}