git.ipfire.org Git - thirdparty/openembedded/openembedded-core-contrib.git/blob

   1 From d0c1a282504a0fa941a9ae22536c73f64d8c5762 Mon Sep 17 00:00:00 2001
   2 From: rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4>
   3 Date: Thu, 21 Apr 2011 14:40:53 +0000
   4 Subject: [PATCH 162/200] 2011-04-21  Richard Guenther  <rguenther@suse.de>
   5
   6         PR middle-end/48695
   7         * tree-ssa-alias.c (aliasing_component_refs_p): Compute base
   8         objects and types here.  Adjust for their offset before
   9         comparing.
  10
  11         * g++.dg/torture/pr48695.C: New testcase.
  12
  13
  14 git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_6-branch@172831 138bc75d-0d04-0410-961f-82ee72b054a4
  15
  16 index e26c75d..3b0e585 100644
  17 new file mode 100644
  18 index 0000000..44e6c77
  19 --- /dev/null
  20 +++ b/gcc/testsuite/g++.dg/torture/pr48695.C
  21 @@ -0,0 +1,38 @@
  22 +// { dg-do run }
  23 +
  24 +typedef __SIZE_TYPE__ size_t;
  25 +
  26 +inline void *operator new (size_t, void *__p) throw() { return __p; }
  27 +
  28 +struct _Vector_impl
  29 +{
  30 +  int *_M_start;
  31 +  int *_M_finish;
  32 +  _Vector_impl () :_M_start (0), _M_finish (0) {}
  33 +};
  34 +
  35 +struct vector
  36 +{
  37 +  _Vector_impl _M_impl;
  38 +  int *_M_allocate (size_t __n)
  39 +  {
  40 +    return __n != 0 ? new int[__n] : 0;
  41 +  }
  42 +  void push_back ()
  43 +  {
  44 +    new (this->_M_impl._M_finish) int ();
  45 +    this->_M_impl._M_finish =
  46 +      this->_M_allocate (this->_M_impl._M_finish - this->_M_impl._M_start) + 1;
  47 +  }
  48 +};
  49 +
  50 +int
  51 +main ()
  52 +{
  53 +  for (int i = 0; i <= 1; i++)
  54 +    for (int j = 0; j <= 1; j++)
  55 +      {
  56 +       vector a[2];
  57 +       a[i].push_back ();
  58 +      }
  59 +}
  60 diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
  61 index bd8953b..8434179 100644
  62 --- a/gcc/tree-ssa-alias.c
  63 +++ b/gcc/tree-ssa-alias.c
  64 @@ -594,11 +594,11 @@ same_type_for_tbaa (tree type1, tree type2)
  65     are the respective alias sets.  */
  66
  67  static bool
  68 -aliasing_component_refs_p (tree ref1, tree type1,
  69 +aliasing_component_refs_p (tree ref1,
  70                            alias_set_type ref1_alias_set,
  71                            alias_set_type base1_alias_set,
  72                            HOST_WIDE_INT offset1, HOST_WIDE_INT max_size1,
  73 -                          tree ref2, tree type2,
  74 +                          tree ref2,
  75                            alias_set_type ref2_alias_set,
  76                            alias_set_type base2_alias_set,
  77                            HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2,
  78 @@ -610,9 +610,21 @@ aliasing_component_refs_p (tree ref1, tree type1,
  79         struct A { int i; int j; } *q;
  80         struct B { struct A a; int k; } *p;
  81       disambiguating q->i and p->a.j.  */
  82 +  tree base1, base2;
  83 +  tree type1, type2;
  84    tree *refp;
  85    int same_p;
  86
  87 +  /* Choose bases and base types to search for.  */
  88 +  base1 = ref1;
  89 +  while (handled_component_p (base1))
  90 +    base1 = TREE_OPERAND (base1, 0);
  91 +  type1 = TREE_TYPE (base1);
  92 +  base2 = ref2;
  93 +  while (handled_component_p (base2))
  94 +    base2 = TREE_OPERAND (base2, 0);
  95 +  type2 = TREE_TYPE (base2);
  96 +
  97    /* Now search for the type1 in the access path of ref2.  This
  98       would be a common base for doing offset based disambiguation on.  */
  99    refp = &ref2;
 100 @@ -628,6 +640,8 @@ aliasing_component_refs_p (tree ref1, tree type1,
 101        HOST_WIDE_INT offadj, sztmp, msztmp;
 102        get_ref_base_and_extent (*refp, &offadj, &sztmp, &msztmp);
 103        offset2 -= offadj;
 104 +      get_ref_base_and_extent (base1, &offadj, &sztmp, &msztmp);
 105 +      offset1 -= offadj;
 106        return ranges_overlap_p (offset1, max_size1, offset2, max_size2);
 107      }
 108    /* If we didn't find a common base, try the other way around.  */
 109 @@ -644,6 +658,8 @@ aliasing_component_refs_p (tree ref1, tree type1,
 110        HOST_WIDE_INT offadj, sztmp, msztmp;
 111        get_ref_base_and_extent (*refp, &offadj, &sztmp, &msztmp);
 112        offset1 -= offadj;
 113 +      get_ref_base_and_extent (base2, &offadj, &sztmp, &msztmp);
 114 +      offset2 -= offadj;
 115        return ranges_overlap_p (offset1, max_size1, offset2, max_size2);
 116      }
 117
 118 @@ -805,11 +821,10 @@ indirect_ref_may_alias_decl_p (tree ref1 ATTRIBUTE_UNUSED, tree base1,
 119        && TREE_CODE (base1) != TARGET_MEM_REF
 120        && (TREE_CODE (base1) != MEM_REF
 121           || same_type_for_tbaa (TREE_TYPE (base1), TREE_TYPE (ptrtype1)) == 1))
 122 -    return aliasing_component_refs_p (ref1, TREE_TYPE (ptrtype1),
 123 +    return aliasing_component_refs_p (ref1,
 124                                       ref1_alias_set, base1_alias_set,
 125                                       offset1, max_size1,
 126 -                                     ref2, TREE_TYPE
 127 -                                             (reference_alias_ptr_type (ref2)),
 128 +                                     ref2,
 129                                       ref2_alias_set, base2_alias_set,
 130                                       offset2, max_size2, true);
 131
 132 @@ -952,10 +967,10 @@ indirect_refs_may_alias_p (tree ref1 ATTRIBUTE_UNUSED, tree base1,
 133           || same_type_for_tbaa (TREE_TYPE (base1), TREE_TYPE (ptrtype1)) == 1)
 134        && (TREE_CODE (base2) != MEM_REF
 135           || same_type_for_tbaa (TREE_TYPE (base2), TREE_TYPE (ptrtype2)) == 1))
 136 -    return aliasing_component_refs_p (ref1, TREE_TYPE (ptrtype1),
 137 +    return aliasing_component_refs_p (ref1,
 138                                       ref1_alias_set, base1_alias_set,
 139                                       offset1, max_size1,
 140 -                                     ref2, TREE_TYPE (ptrtype2),
 141 +                                     ref2,
 142                                       ref2_alias_set, base2_alias_set,
 143                                       offset2, max_size2, false);
 144
 145 --
 146 1.7.0.4
 147