2006-01-18 Andrew Pinski <pinskia@physics.uc.edu>

[pf3gnuchains/gcc-fork.git] / gcc / cfgexpand.c

diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index 7c58e55..f3a340a 100644 (file)
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -285,14 +285,14 @@ add_alias_set_conflicts (void)
 
   for (i = 0; i < n; ++i)
     {
-      bool aggr_i = AGGREGATE_TYPE_P (TREE_TYPE (stack_vars[i].decl));
-      HOST_WIDE_INT set_i = get_alias_set (stack_vars[i].decl);
+      tree type_i = TREE_TYPE (stack_vars[i].decl);
+      bool aggr_i = AGGREGATE_TYPE_P (type_i);
 
       for (j = 0; j < i; ++j)
        {
-         bool aggr_j = AGGREGATE_TYPE_P (TREE_TYPE (stack_vars[j].decl));
-         HOST_WIDE_INT set_j = get_alias_set (stack_vars[j].decl);
-         if (aggr_i != aggr_j || !alias_sets_conflict_p (set_i, set_j))
+         tree type_j = TREE_TYPE (stack_vars[j].decl);
+         bool aggr_j = AGGREGATE_TYPE_P (type_j);
+         if (aggr_i != aggr_j || !objects_must_conflict_p (type_i, type_j))
            add_stack_var_conflict (i, j);
        }
     }
@@ -1463,6 +1463,67 @@ construct_exit_block (void)
   update_bb_for_insn (exit_block);
 }
 
+/* Helper function for discover_nonconstant_array_refs. 
+   Look for ARRAY_REF nodes with non-constant indexes and mark them
+   addressable.  */
+
+static tree
+discover_nonconstant_array_refs_r (tree * tp, int *walk_subtrees,
+                                  void *data ATTRIBUTE_UNUSED)
+{
+  tree t = *tp;
+
+  if (IS_TYPE_OR_DECL_P (t))
+    *walk_subtrees = 0;
+  else if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
+    {
+      while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
+             && is_gimple_min_invariant (TREE_OPERAND (t, 1))
+             && (!TREE_OPERAND (t, 2)
+                 || is_gimple_min_invariant (TREE_OPERAND (t, 2))))
+            || (TREE_CODE (t) == COMPONENT_REF
+                && (!TREE_OPERAND (t,2)
+                    || is_gimple_min_invariant (TREE_OPERAND (t, 2))))
+            || TREE_CODE (t) == BIT_FIELD_REF
+            || TREE_CODE (t) == REALPART_EXPR
+            || TREE_CODE (t) == IMAGPART_EXPR
+            || TREE_CODE (t) == VIEW_CONVERT_EXPR
+            || TREE_CODE (t) == NOP_EXPR
+            || TREE_CODE (t) == CONVERT_EXPR)
+       t = TREE_OPERAND (t, 0);
+
+      if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
+       {
+         t = get_base_address (t);
+         if (t && DECL_P (t))
+           TREE_ADDRESSABLE (t) = 1;
+       }
+
+      *walk_subtrees = 0;
+    }
+
+  return NULL_TREE;
+}
+
+/* RTL expansion is not able to compile array references with variable
+   offsets for arrays stored in single register.  Discover such
+   expressions and mark variables as addressable to avoid this
+   scenario.  */
+
+static void
+discover_nonconstant_array_refs (void)
+{
+  basic_block bb;
+  block_stmt_iterator bsi;
+
+  FOR_EACH_BB (bb)
+    {
+      for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+       walk_tree (bsi_stmt_ptr (bsi), discover_nonconstant_array_refs_r,
+                  NULL , NULL);
+    }
+}
+
 /* Translate the intermediate representation contained in the CFG
    from GIMPLE trees to RTL.
 
@@ -1484,6 +1545,9 @@ tree_expand_cfg (void)
   /* Prepare the rtl middle end to start recording block changes.  */
   reset_block_changes ();
 
+  /* Mark arrays indexed with non-constant indices with TREE_ADDRESSABLE.  */
+  discover_nonconstant_array_refs ();
+
   /* Expand the variables recorded during gimple lowering.  */
   expand_used_vars ();