gcc/testsuite/gcc.dg/string-opt-1.c

   1 /* Ensure mempcpy is "optimized" into memcpy followed by addition.  */
   2 /* { dg-do compile } */
   3 /* { dg-options "-O2" } */
   4
   5 char *buffer;
   6 char *test;
   7
   8 #define SIZE 100
   9
  10 char *
  11 __attribute__((noinline))
  12 my_memcpy (char *d, char *s, unsigned l)
  13 {
  14   return __builtin_memcpy (d, s, l);
  15 }
  16
  17 char *
  18 __attribute__((noinline))
  19 my_mempcpy (char *d, char *s, unsigned l)
  20 {
  21   return __builtin_mempcpy (d, s, l);
  22 }
  23
  24 void
  25 run_test (char *d, char *s, unsigned l)
  26 {
  27   char *r = my_mempcpy (d, s, l);
  28   if (r != d + l)
  29     __builtin_abort ();
  30
  31   r = my_memcpy (d, s, l);
  32   if (r != d)
  33     __builtin_abort ();
  34 }
  35
  36 int
  37 main (void)
  38 {
  39   const char* const foo = "hello world";
  40   unsigned l = __builtin_strlen (foo) + 1;
  41
  42   buffer = __builtin_malloc (SIZE);
  43   __builtin_memcpy (buffer, foo, l);
  44   test = __builtin_malloc (SIZE);
  45
  46   run_test (test, buffer, l);
  47
  48   return 0;
  49 }
  50
  51 /* { dg-final { scan-assembler-not "\<mempcpy\>" } } */
  52 /* { dg-final { scan-assembler "memcpy" } } */