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

   1 Upstream-Status: Inappropriate [Backport]
   2 From d0c1a282504a0fa941a9ae22536c73f64d8c5762 Mon Sep 17 00:00:00 2001
   3 From: rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4>
   4 Date: Thu, 21 Apr 2011 14:40:53 +0000
   5 Subject: [PATCH 162/200] 2011-04-21  Richard Guenther  <rguenther@suse.de>
   6
   7         PR middle-end/48695
   8         * tree-ssa-alias.c (aliasing_component_refs_p): Compute base
   9         objects and types here.  Adjust for their offset before
  10         comparing.
  11
  12         * g++.dg/torture/pr48695.C: New testcase.
  13
  14
  15 git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_6-branch@172831 138bc75d-0d04-0410-961f-82ee72b054a4
  16
  17 index e26c75d..3b0e585 100644
  18 new file mode 100644
  19 index 0000000..44e6c77
  20 --- /dev/null
  21 +++ b/gcc/testsuite/g++.dg/torture/pr48695.C
  22 @@ -0,0 +1,38 @@
  23 +// { dg-do run }
  24 +
  25 +typedef __SIZE_TYPE__ size_t;
  26 +
  27 +inline void *operator new (size_t, void *__p) throw() { return __p; }
  28 +
  29 +struct _Vector_impl
  30 +{
  31 +  int *_M_start;
  32 +  int *_M_finish;
  33 +  _Vector_impl () :_M_start (0), _M_finish (0) {}
  34 +};
  35 +
  36 +struct vector
  37 +{
  38 +  _Vector_impl _M_impl;
  39 +  int *_M_allocate (size_t __n)
  40 +  {
  41 +    return __n != 0 ? new int[__n] : 0;
  42 +  }
  43 +  void push_back ()
  44 +  {
  45 +    new (this->_M_impl._M_finish) int ();
  46 +    this->_M_impl._M_finish =
  47 +      this->_M_allocate (this->_M_impl._M_finish - this->_M_impl._M_start) + 1;
  48 +  }
  49 +};
  50 +
  51 +int
  52 +main ()
  53 +{
  54 +  for (int i = 0; i <= 1; i++)
  55 +    for (int j = 0; j <= 1; j++)
  56 +      {
  57 +       vector a[2];
  58 +       a[i].push_back ();
  59 +      }
  60 +}
  61 diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
  62 index bd8953b..8434179 100644
  63 --- a/gcc/tree-ssa-alias.c
  64 +++ b/gcc/tree-ssa-alias.c
  65 @@ -594,11 +594,11 @@ same_type_for_tbaa (tree type1, tree type2)
  66     are the respective alias sets.  */
  67
  68  static bool
  69 -aliasing_component_refs_p (tree ref1, tree type1,
  70 +aliasing_component_refs_p (tree ref1,
  71                            alias_set_type ref1_alias_set,
  72                            alias_set_type base1_alias_set,
  73                            HOST_WIDE_INT offset1, HOST_WIDE_INT max_size1,
  74 -                          tree ref2, tree type2,
  75 +                          tree ref2,
  76                            alias_set_type ref2_alias_set,
  77                            alias_set_type base2_alias_set,
  78                            HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2,
  79 @@ -610,9 +610,21 @@ aliasing_component_refs_p (tree ref1, tree type1,
  80         struct A { int i; int j; } *q;
  81         struct B { struct A a; int k; } *p;
  82       disambiguating q->i and p->a.j.  */
  83 +  tree base1, base2;
  84 +  tree type1, type2;
  85    tree *refp;
  86    int same_p;
  87
  88 +  /* Choose bases and base types to search for.  */
  89 +  base1 = ref1;
  90 +  while (handled_component_p (base1))
  91 +    base1 = TREE_OPERAND (base1, 0);
  92 +  type1 = TREE_TYPE (base1);
  93 +  base2 = ref2;
  94 +  while (handled_component_p (base2))
  95 +    base2 = TREE_OPERAND (base2, 0);
  96 +  type2 = TREE_TYPE (base2);
  97 +
  98    /* Now search for the type1 in the access path of ref2.  This
  99       would be a common base for doing offset based disambiguation on.  */
 100    refp = &ref2;
 101 @@ -628,6 +640,8 @@ aliasing_component_refs_p (tree ref1, tree type1,
 102        HOST_WIDE_INT offadj, sztmp, msztmp;
 103        get_ref_base_and_extent (*refp, &offadj, &sztmp, &msztmp);
 104        offset2 -= offadj;
 105 +      get_ref_base_and_extent (base1, &offadj, &sztmp, &msztmp);
 106 +      offset1 -= offadj;
 107        return ranges_overlap_p (offset1, max_size1, offset2, max_size2);
 108      }
 109    /* If we didn't find a common base, try the other way around.  */
 110 @@ -644,6 +658,8 @@ aliasing_component_refs_p (tree ref1, tree type1,
 111        HOST_WIDE_INT offadj, sztmp, msztmp;
 112        get_ref_base_and_extent (*refp, &offadj, &sztmp, &msztmp);
 113        offset1 -= offadj;
 114 +      get_ref_base_and_extent (base2, &offadj, &sztmp, &msztmp);
 115 +      offset2 -= offadj;
 116        return ranges_overlap_p (offset1, max_size1, offset2, max_size2);
 117      }
 118
 119 @@ -805,11 +821,10 @@ indirect_ref_may_alias_decl_p (tree ref1 ATTRIBUTE_UNUSED, tree base1,
 120        && TREE_CODE (base1) != TARGET_MEM_REF
 121        && (TREE_CODE (base1) != MEM_REF
 122           || same_type_for_tbaa (TREE_TYPE (base1), TREE_TYPE (ptrtype1)) == 1))
 123 -    return aliasing_component_refs_p (ref1, TREE_TYPE (ptrtype1),
 124 +    return aliasing_component_refs_p (ref1,
 125                                       ref1_alias_set, base1_alias_set,
 126                                       offset1, max_size1,
 127 -                                     ref2, TREE_TYPE
 128 -                                             (reference_alias_ptr_type (ref2)),
 129 +                                     ref2,
 130                                       ref2_alias_set, base2_alias_set,
 131                                       offset2, max_size2, true);
 132
 133 @@ -952,10 +967,10 @@ indirect_refs_may_alias_p (tree ref1 ATTRIBUTE_UNUSED, tree base1,
 134           || same_type_for_tbaa (TREE_TYPE (base1), TREE_TYPE (ptrtype1)) == 1)
 135        && (TREE_CODE (base2) != MEM_REF
 136           || same_type_for_tbaa (TREE_TYPE (base2), TREE_TYPE (ptrtype2)) == 1))
 137 -    return aliasing_component_refs_p (ref1, TREE_TYPE (ptrtype1),
 138 +    return aliasing_component_refs_p (ref1,
 139                                       ref1_alias_set, base1_alias_set,
 140                                       offset1, max_size1,
 141 -                                     ref2, TREE_TYPE (ptrtype2),
 142 +                                     ref2,
 143                                       ref2_alias_set, base2_alias_set,
 144                                       offset2, max_size2, false);
 145
 146 --
 147 1.7.0.4
 148