gcc/testsuite/gcc.dg/strlenopt-2.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 buf[26];
  10   if (strlen (p) + strlen (r) + 9 > 26)
  11     return NULL;
  12   /* This strcpy can be optimized into memcpy, using the remembered
  13      strlen (p).  */
  14   strcpy (buf, p);
  15   /* These two strcat can be optimized into memcpy.  The first one
  16      could be even optimized into a *ptr = '/'; store as the '\0'
  17      is immediately overwritten.  */
  18   strcat (buf, "/");
  19   strcat (buf, "abcde");
  20   /* This strcpy can be optimized into memcpy, using the remembered
  21      strlen (r).  */
  22   strcat (buf, r);
  23   /* And this can be optimized into memcpy too.  */
  24   strcat (buf, "fg");
  25   return strdup (buf);
  26 }
  27
  28 int
  29 main ()
  30 {
  31   char *volatile p = "string1";
  32   char *volatile r = "string2";
  33   char *q = foo (p, r);
  34   if (q != NULL)
  35     {
  36       if (strcmp (q, "string1/abcdestring2fg"))
  37         abort ();
  38       free (q);
  39     }
  40   return 0;
  41 }
  42
  43 /* { dg-final { scan-tree-dump-times "strlen \\(" 2 "strlen" } } */
  44 /* { dg-final { scan-tree-dump-times "memcpy \\(" 5 "strlen" } } */
  45 /* { dg-final { scan-tree-dump-times "strcpy \\(" 0 "strlen" } } */
  46 /* { dg-final { scan-tree-dump-times "strcat \\(" 0 "strlen" } } */
  47 /* { dg-final { scan-tree-dump-times "strchr \\(" 0 "strlen" } } */
  48 /* { dg-final { scan-tree-dump-times "stpcpy \\(" 0 "strlen" } } */