gcc/testsuite/gcc.dg/strlenopt-10.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -fdump-tree-strlen" } */
   3
   4 #include "strlenopt.h"
   5
   6 __attribute__((noinline, noclone)) size_t
   7 fn1 (char *p)
   8 {
   9   char *q;
  10   /* This can be optimized into memcpy and the size can be decreased to one,
  11      as it is immediately overwritten.  */
  12   strcpy (p, "z");
  13   q = strchr (p, '\0');
  14   *q = 32;
  15   /* This strlen can't be optimized away, string length is unknown here.  */
  16   return strlen (p);
  17 }
  18
  19 __attribute__((noinline, noclone)) void
  20 fn2 (char *p, const char *z, size_t *lp)
  21 {
  22   char *q, *r;
  23   char buf[64];
  24   size_t l[10];
  25   /* The first strlen stays, all the strcpy calls can be optimized
  26      into memcpy and all other strlen calls and all strchr calls
  27      optimized away.  */
  28   l[0] = strlen (z);
  29   strcpy (buf, z);
  30   strcpy (p, "abcde");
  31   q = strchr (p, '\0');
  32   strcpy (q, "efghi");
  33   r = strchr (q, '\0');
  34   strcpy (r, "jkl");
  35   l[1] = strlen (p);
  36   l[2] = strlen (q);
  37   l[3] = strlen (r);
  38   strcpy (r, buf);
  39   l[4] = strlen (p);
  40   l[5] = strlen (q);
  41   l[6] = strlen (r);
  42   strcpy (r, "mnopqr");
  43   l[7] = strlen (p);
  44   l[8] = strlen (q);
  45   l[9] = strlen (r);
  46   memcpy (lp, l, sizeof l);
  47 }
  48
  49 int
  50 main ()
  51 {
  52   char buf[64];
  53   size_t l[10];
  54   const char *volatile z = "ABCDEFG";
  55   memset (buf, '\0', sizeof buf);
  56   if (fn1 (buf) != 2 || buf[0] != 'z' || buf[1] != 32 || buf[2] != '\0')
  57     abort ();
  58   fn2 (buf, z, l);
  59   if (memcmp (buf, "abcdeefghimnopqr", 17) != 0)
  60     abort ();
  61   if (l[0] != 7)
  62     abort ();
  63   if (l[1] != 13 || l[2] != 8 || l[3] != 3)
  64     abort ();
  65   if (l[4] != 17 || l[5] != 12 || l[6] != 7)
  66     abort ();
  67   if (l[7] != 16 || l[8] != 11 || l[9] != 6)
  68     abort ();
  69   return 0;
  70 }
  71
  72 /* { dg-final { scan-tree-dump-times "strlen \\(" 2 "strlen" } } */
  73 /* avr has BIGGEST_ALIGNMENT 8, allowing fold_builtin_memory_op
  74    to expand the memcpy call at the end of fn2.  */
  75 /* { dg-final { scan-tree-dump-times "memcpy \\(" 8 "strlen" { target { ! avr-*-* } } } } */
  76 /* { dg-final { scan-tree-dump-times "memcpy \\(" 7 "strlen" { target { avr-*-* } } } } */
  77 /* { dg-final { scan-tree-dump-times "strcpy \\(" 0 "strlen" } } */
  78 /* { dg-final { scan-tree-dump-times "strcat \\(" 0 "strlen" } } */
  79 /* { dg-final { scan-tree-dump-times "strchr \\(" 0 "strlen" } } */
  80 /* { dg-final { scan-tree-dump-times "stpcpy \\(" 0 "strlen" } } */
  81 /* { dg-final { scan-tree-dump-times "\\*q_\[0-9\]* = 32;" 1 "strlen" } } */
  82 /* { dg-final { scan-tree-dump-times "memcpy \\(\[^\n\r\]*, 1\\)" 1 "strlen" } } */