gcc/testsuite/gcc.dg/strlenopt-21.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -fdump-tree-strlen" } */
   3
   4 #include "strlenopt.h"
   5
   6 struct S { char *p; size_t l; };
   7
   8 __attribute__((noinline, noclone)) struct S
   9 foo (char *x, int n)
  10 {
  11   int i;
  12   char a[64];
  13   char *p = strchr (x, '\0');
  14   struct S s;
  15   /* strcpy here is optimized into memcpy, length computed as p - x + 1.  */
  16   strcpy (a, x);
  17   /* strcat here is optimized into memcpy.  */
  18   strcat (p, "abcd");
  19   for (i = 0; i < n; i++)
  20     if ((i % 123) == 53)
  21       /* strcat here is optimized into strlen and memcpy.  */
  22       strcat (a, "efg");
  23   s.p = strdup (a);
  24   /* The strlen should be optimized here into 4.  */
  25   s.l = strlen (p);
  26   return s;
  27 }
  28
  29 int
  30 main ()
  31 {
  32   char buf[32];
  33   struct S s;
  34   buf[0] = 'z';
  35   buf[1] = '\0';
  36   s = foo (buf, 0);
  37   if (s.l != 4 || memcmp (buf, "zabcd", 6) != 0)
  38     abort ();
  39   if (s.p == NULL)
  40     return 0;
  41   if (memcmp (s.p, "z", 2) != 0)
  42     abort ();
  43   s = foo (buf, 60);
  44   if (s.l != 4 || memcmp (buf, "zabcdabcd", 10) != 0)
  45     abort ();
  46   if (s.p == NULL)
  47     return 0;
  48   if (memcmp (s.p, "zabcdefg", 9) != 0)
  49     abort ();
  50   s = foo (buf, 240);
  51   if (s.l != 4 || memcmp (buf, "zabcdabcdabcd", 14) != 0)
  52     abort ();
  53   if (s.p == NULL)
  54     return 0;
  55   if (memcmp (s.p, "zabcdabcdefgefg", 16) != 0)
  56     abort ();
  57   return 0;
  58 }
  59
  60 /* { dg-final { scan-tree-dump-times "strlen \\(" 2 "strlen" } } */
  61 /* { dg-final { scan-tree-dump-times "memcpy \\(" 3 "strlen" } } */
  62 /* { dg-final { scan-tree-dump-times "strcpy \\(" 0 "strlen" } } */
  63 /* { dg-final { scan-tree-dump-times "strcat \\(" 0 "strlen" } } */
  64 /* { dg-final { scan-tree-dump-times "strchr \\(" 0 "strlen" } } */
  65 /* { dg-final { scan-tree-dump-times "stpcpy \\(" 0 "strlen" } } */