gcc/testsuite/gcc.dg/strlenopt-1.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -fdump-tree-strlen" } */
   3
   4 #include "strlenopt.h"
   5
   6 __attribute__((noinline, noclone)) char *
   7 foo (char *p, char *r)
   8 {
   9   char *q = malloc (strlen (p) + strlen (r) + 64);
  10   if (q == NULL) return NULL;
  11   /* This strcpy can be optimized into memcpy, using the remembered
  12      strlen (p).  */
  13   strcpy (q, p);
  14   /* These two strcat can be optimized into memcpy.  The first one
  15      could be even optimized into a *ptr = '/'; store as the '\0'
  16      is immediately overwritten.  */
  17   strcat (q, "/");
  18   strcat (q, "abcde");
  19   /* This can also be optimized into memcpy.  */
  20   strcat (q, r);
  21   return q;
  22 }
  23
  24 int
  25 main ()
  26 {
  27   char *volatile p = "string1";
  28   char *volatile r = "string2";
  29   char *q = foo (p, r);
  30   if (q != NULL)
  31     {
  32       if (strcmp (q, "string1/abcdestring2"))
  33         abort ();
  34       free (q);
  35     }
  36   return 0;
  37 }
  38
  39 /* { dg-final { scan-tree-dump-times "strlen \\(" 2 "strlen" } } */
  40 /* { dg-final { scan-tree-dump-times "memcpy \\(" 4 "strlen" } } */
  41 /* { dg-final { scan-tree-dump-times "strcpy \\(" 0 "strlen" } } */
  42 /* { dg-final { scan-tree-dump-times "strcat \\(" 0 "strlen" } } */
  43 /* { dg-final { scan-tree-dump-times "strchr \\(" 0 "strlen" } } */
  44 /* { dg-final { scan-tree-dump-times "stpcpy \\(" 0 "strlen" } } */