gnu/dist/gcc4/gcc/testsuite/gcc.target/i386/pr20204.c

   1 /* { dg-do run { target i?86-*-* x86_64-*-* } } */
   2 /* { dg-options "-O2" } */
   3
   4 void *x (void *pdst, const void *psrc, unsigned int pn)
   5 {
   6   register void *return_dst = pdst;
   7   register unsigned char *dst = pdst;
   8   register unsigned const char *src = psrc;
   9   register int n __asm__ ("ebx") = pn;
  10
  11   if (src < dst && dst < src + n)
  12     {
  13       src += n;
  14       dst += n;
  15       while (n--)
  16         *--dst = *--src;
  17       return return_dst;
  18     }
  19
  20   while (n >= 16) n--;
  21
  22   return return_dst;
  23 }
  24 extern void abort ();
  25 extern void exit (int);
  26 char xx[30] = "abc";
  27 int main (void)
  28 {
  29   char yy[30] = "aab";
  30
  31   if (x (xx + 1, xx, 2) != xx + 1 || memcmp (xx, yy, sizeof (yy)) != 0)
  32     abort ();
  33   exit (0);
  34 }