gcc/testsuite/gcc.dg/strcmpopt_10.c

   1 /* Verify that strncmp equalities aren't eliminated when the trailing array
   2    type referenced by a member pointer is smaller than the string in cases
   3    when the pointer pointed to by the enclosing object references an object
   4    sufficiently large to store a string of equal length.
   5   { dg-do compile }
   6   { dg-options "-O2 -Wall -Wextra -Wno-stringop-overread -fdump-tree-optimized" } */
   7
   8 void init (void*);
   9
  10 struct A1 { char i, a[1]; };
  11
  12 void f1_arr (void)
  13 {
  14   char a[9];
  15   init (a);
  16
  17   struct A1 *p = (struct A1*)a;
  18
  19   if (__builtin_strncmp (p->a, "01234567", 8) == 0)
  20     {
  21       extern void array_test (void);
  22       array_test ();
  23     }
  24 }
  25
  26 void f1_ptr (void)
  27 {
  28   void *p;
  29   init (&p);
  30
  31   struct A1 *q = (struct A1*)p;
  32
  33   if (__builtin_strncmp (q->a, "0123456789", 10) == 0)
  34     {
  35       extern void pointer_test (void);
  36       pointer_test ();
  37     }
  38 }
  39
  40 void f1_struct (void)
  41 {
  42   struct { char a[9]; } b;
  43   init (&b);
  44
  45   struct A1 *p = (struct A1*)&b;
  46
  47   if (__builtin_strncmp (p->a, "01234567", 8) == 0)
  48     {
  49       extern void struct_test (void);
  50       struct_test ();
  51     }
  52 }
  53
  54 void f1_memptr (void)
  55 {
  56   struct { void *p; } b;
  57   init (&b);
  58
  59   struct A1 *p = (struct A1*)b.p;
  60
  61   if (__builtin_strncmp (p->a, "0123456789", 10) == 0)
  62     {
  63       extern void memptr_test (void);
  64       memptr_test ();
  65     }
  66 }
  67
  68
  69 struct A2 { char i, a[2]; };
  70
  71 void f2_arr (void)
  72 {
  73   char a[8];
  74   init (a);
  75
  76   struct A2 *p = (struct A2*)a;
  77
  78   if (__builtin_strncmp (p->a, "0123456", 7) == 0)
  79     {
  80       extern void array_test (void);
  81       array_test ();
  82     }
  83 }
  84
  85 void f2_ptr (void)
  86 {
  87   void *p;
  88   init (&p);
  89
  90   struct A2 *q = (struct A2*)p;
  91
  92   if (__builtin_strncmp (q->a, "0123456789", 10) == 0)
  93     {
  94       extern void pointer_test (void);
  95       pointer_test ();
  96     }
  97 }
  98
  99 void f2_struct (void)
 100 {
 101   struct { char a[8]; } b;
 102   init (&b);
 103
 104   struct A2 *p = (struct A2*)&b;
 105
 106   if (__builtin_strncmp (p->a, "0123456", 7) == 0)
 107     {
 108       extern void struct_test (void);
 109       struct_test ();
 110     }
 111 }
 112
 113 void f2_memptr (void)
 114 {
 115   struct { void *p; } b;
 116   init (&b);
 117
 118   struct A2 *p = (struct A2*)b.p;
 119
 120   if (__builtin_strncmp (p->a, "0123456789", 10) == 0)
 121     {
 122       extern void memptr_test (void);
 123       memptr_test ();
 124     }
 125 }
 126
 127 /* { dg-final { scan-tree-dump-times "array_test" 2 "optimized" } }
 128    { dg-final { scan-tree-dump-times "pointer_test" 2 "optimized" } }
 129    { dg-final { scan-tree-dump-times "struct_test" 2 "optimized" } }
 130    { dg-final { scan-tree-dump-times "memptr_test" 2 "optimized" } } */