tree-ssa-alias.c (aliasing_component_refs_p): Consider only the access path from...

	* tree-ssa-alias.c (aliasing_component_refs_p): Consider only
	the access path from base to first VIEW_CONVERT_EXPR or
	BIT_FIELD_REF.

From-SVN: r272383

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 43519721ee6e47823291d3b0efaaeae2916149cc..f11854438aa8442457a19c9f5eef2536c7826ef8 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2019-06-17  Jan Hubicka  <hubicka@ucw.cz>
+
+       * tree-ssa-alias.c (aliasing_component_refs_p): Consider only
+       the access path from base to first VIEW_CONVERT_EXPR or
+       BIT_FIELD_REF.
+
 2019-06-17  Jan Hubicka  <hubicka@ucw.cz>
 
        * tree-ssa-alias.c (nonoverlapping_component_refs_p): Also truncate

diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
index 399e06c3825b6d926cd066127194481e85642608..867b4cb53f2804aaf72d640992c0d2781708adca 100644 (file)
--- a/gcc/tree-ssa-alias.c
+++ b/gcc/tree-ssa-alias.c
@@ -874,7 +874,6 @@ aliasing_component_refs_p (tree ref1,
      disambiguating q->i and p->a.j.  */
   tree base1, base2;
   tree type1, type2;
-  tree *refp;
   int same_p1 = 0, same_p2 = 0;
   bool maybe_match = false;
   tree end_struct_ref1 = NULL, end_struct_ref2 = NULL;
@@ -903,6 +902,9 @@ aliasing_component_refs_p (tree ref1,
          gcc_checking_assert (!end_struct_ref1);
           end_struct_ref1 = base1;
        }
+      if (TREE_CODE (base1) == VIEW_CONVERT_EXPR
+         || TREE_CODE (base1) == BIT_FIELD_REF)
+       ref1 = TREE_OPERAND (base1, 0);
       base1 = TREE_OPERAND (base1, 0);
     }
   type1 = TREE_TYPE (base1);
@@ -918,6 +920,9 @@ aliasing_component_refs_p (tree ref1,
          gcc_checking_assert (!end_struct_ref2);
          end_struct_ref2 = base2;
        }
+      if (TREE_CODE (base2) == VIEW_CONVERT_EXPR
+         || TREE_CODE (base2) == BIT_FIELD_REF)
+       ref2 = TREE_OPERAND (base2, 0);
       base2 = TREE_OPERAND (base2, 0);
     }
   type2 = TREE_TYPE (base2);
@@ -934,23 +939,23 @@ aliasing_component_refs_p (tree ref1,
       || (end_struct_ref2
          && compare_type_sizes (TREE_TYPE (end_struct_ref2), type1) >= 0))
     {
-      refp = &ref2;
+      tree ref = ref2;
       while (true)
        {
          /* We walk from inner type to the outer types. If type we see is
             already too large to be part of type1, terminate the search.  */
-         int cmp = compare_type_sizes (type1, TREE_TYPE (*refp));
+         int cmp = compare_type_sizes (type1, TREE_TYPE (ref));
 
          if (cmp < 0
              && (!end_struct_ref1
                  || compare_type_sizes (TREE_TYPE (end_struct_ref1),
-                                        TREE_TYPE (*refp)) < 0))
+                                        TREE_TYPE (ref)) < 0))
            break;
          /* If types may be of same size, see if we can decide about their
             equality.  */
          if (cmp == 0)
            {
-             same_p2 = same_type_for_tbaa (TREE_TYPE (*refp), type1);
+             same_p2 = same_type_for_tbaa (TREE_TYPE (ref), type1);
              if (same_p2 == 1)
                break;
              /* In case we can't decide whether types are same try to
@@ -960,9 +965,9 @@ aliasing_component_refs_p (tree ref1,
              if (same_p2 == -1)
                maybe_match = true;
            }
-         if (!handled_component_p (*refp))
+         if (!handled_component_p (ref))
            break;
-         refp = &TREE_OPERAND (*refp, 0);
+         ref = TREE_OPERAND (ref, 0);
        }
       if (same_p2 == 1)
        {
@@ -977,13 +982,13 @@ aliasing_component_refs_p (tree ref1,
          if (TREE_CODE (TREE_TYPE (base1)) == ARRAY_TYPE
              && (!TYPE_SIZE (TREE_TYPE (base1))
                  || TREE_CODE (TYPE_SIZE (TREE_TYPE (base1))) != INTEGER_CST
-                 || (*refp == base2 && !ref2_is_decl)))
+                 || (ref == base2 && !ref2_is_decl)))
            {
              ++alias_stats.aliasing_component_refs_p_may_alias;
              return true;
            }
 
-         get_ref_base_and_extent (*refp, &offadj, &sztmp, &msztmp, &reverse);
+         get_ref_base_and_extent (ref, &offadj, &sztmp, &msztmp, &reverse);
          offset2 -= offadj;
          get_ref_base_and_extent (base1, &offadj, &sztmp, &msztmp, &reverse);
          offset1 -= offadj;
@@ -1005,28 +1010,28 @@ aliasing_component_refs_p (tree ref1,
       || (end_struct_ref1
          && compare_type_sizes (TREE_TYPE (end_struct_ref1), type1) <= 0))
     {
-      refp = &ref1;
+      tree ref = ref1;
       while (true)
        {
-         int cmp = compare_type_sizes (type2, TREE_TYPE (*refp));
+         int cmp = compare_type_sizes (type2, TREE_TYPE (ref));
          if (cmp < 0
              && (!end_struct_ref2
                  || compare_type_sizes (TREE_TYPE (end_struct_ref2),
-                                        TREE_TYPE (*refp)) < 0))
+                                        TREE_TYPE (ref)) < 0))
            break;
          /* If types may be of same size, see if we can decide about their
             equality.  */
          if (cmp == 0)
            {
-             same_p1 = same_type_for_tbaa (TREE_TYPE (*refp), type2);
+             same_p1 = same_type_for_tbaa (TREE_TYPE (ref), type2);
              if (same_p1 == 1)
                break;
              if (same_p1 == -1)
                maybe_match = true;
            }
-         if (!handled_component_p (*refp))
+         if (!handled_component_p (ref))
            break;
-         refp = &TREE_OPERAND (*refp, 0);
+         ref = TREE_OPERAND (ref, 0);
        }
       if (same_p1 == 1)
        {
@@ -1036,13 +1041,13 @@ aliasing_component_refs_p (tree ref1,
          if (TREE_CODE (TREE_TYPE (base2)) == ARRAY_TYPE
              && (!TYPE_SIZE (TREE_TYPE (base2))
                  || TREE_CODE (TYPE_SIZE (TREE_TYPE (base2))) != INTEGER_CST
-                 || (*refp == base1 && !ref2_is_decl)))
+                 || (ref == base1 && !ref2_is_decl)))
            {
              ++alias_stats.aliasing_component_refs_p_may_alias;
              return true;
            }
 
-         get_ref_base_and_extent (*refp, &offadj, &sztmp, &msztmp, &reverse);
+         get_ref_base_and_extent (ref, &offadj, &sztmp, &msztmp, &reverse);
          offset1 -= offadj;
          get_ref_base_and_extent (base2, &offadj, &sztmp, &msztmp, &reverse);
          offset2 -= offadj;