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   /* Due to inefficient PTA (PR50262) the above calls invalidate
  20      string length of r, so it is optimized just into strcpy instead
  21      of memcpy.  */
  22   strcat (q, r);
  23   return q;
  24 }
  25
  26 int
  27 main ()
  28 {
  29   char *volatile p = "string1";
  30   char *volatile r = "string2";
  31   char *q = foo (p, r);
  32   if (q != NULL)
  33     {
  34       if (strcmp (q, "string1/abcdestring2"))
  35         abort ();
  36       free (q);
  37     }
  38   return 0;
  39 }
  40
  41 /* { dg-final { scan-tree-dump-times "strlen \\(" 2 "strlen" } } */
  42 /* { dg-final { scan-tree-dump-times "memcpy \\(" 3 "strlen" } } */
  43 /* { dg-final { scan-tree-dump-times "strcpy \\(" 1 "strlen" } } */
  44 /* { dg-final { scan-tree-dump-times "strcat \\(" 0 "strlen" } } */
  45 /* { dg-final { scan-tree-dump-times "strchr \\(" 0 "strlen" } } */
  46 /* { dg-final { scan-tree-dump-times "stpcpy \\(" 0 "strlen" } } */
  47 /* { dg-final { cleanup-tree-dump "strlen" } } */