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| | #include <string.h>
#include <stdint.h>
#include <limits.h>
#include "libc.h"
#define ALIGN (sizeof(size_t))
#define ONES ((size_t)-1/UCHAR_MAX)
#define HIGHS (ONES * (UCHAR_MAX/2+1))
#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)
char *__stpcpy(char *restrict d, const char *restrict s)
{
#ifdef __GNUC__
size_t __attribute__((__may_alias__)) *wd;
const size_t __attribute__((__may_alias__)) *ws;
if ((uintptr_t)s % ALIGN == (uintptr_t)d % ALIGN) {
for (; (uintptr_t)s % ALIGN; s++, d++)
if (!(*d=*s)) return d;
wd=(void *)d; ws=(const void *)s;
for (; !HASZERO(*ws); *wd++ = *ws++);
d=(void *)wd; s=(const void *)ws;
}
#endif
for (; (*d=*s); s++, d++);
return d;
}
weak_alias(__stpcpy, stpcpy);
|