gimplify.c (find_single_pointer_decl_1): New static function.

	* gimplify.c (find_single_pointer_decl_1): New static function.
	(find_single_pointer_decl): New static function.
	(internal_get_tmp_var): For a formal variable, set restrict base
	information if appropriate.
	* alias.c (find_base_decl): If a VAR_DECL has a restrict base,
	return it.
	* tree.h (DECL_BASED_ON_RESTRICT_P): Define.
	(DECL_GET_RESTRICT_BASE): Define.
	(SET_DECL_RESTRICT_BASE): Define.
	(decl_restrict_base_lookup): Declare.
	(decl_restrict_base_insert): Declare.
	(struct tree_decl_with_vis): Add based_on_restrict_p field.
	* tree.c (restrict_base_for_decl): New static variable.
	(init_ttree): Initialize restrict_base_for_decl.
	(copy_node_stat): Copy restrict base information.
	(decl_restrict_base_lookup): New function.
	(decl_restrict_base_insert): New function.
	(print_restrict_base_statistics): New static function.
	(dump_tree_statistics): Call print_restrict_base_statistics.

From-SVN: r104890

1 files changed, 60 insertions, 0 deletions

diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index e5d50e2..7047918 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -298,6 +298,48 @@ create_artificial_label (void)
   return lab;
 }
 
+/* Subroutine for find_single_pointer_decl.  */
+
+static tree
+find_single_pointer_decl_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
+			    void *data)
+{
+  tree *pdecl = (tree *) data;
+
+  if (DECL_P (*tp) && POINTER_TYPE_P (TREE_TYPE (*tp)))
+    {
+      if (*pdecl)
+	{
+	  /* We already found a pointer decl; return anything other
+	     than NULL_TREE to unwind from walk_tree signalling that
+	     we have a duplicate.  */
+	  return *tp;
+	}
+      *pdecl = *tp;
+    }
+
+  return NULL_TREE;
+}
+
+/* Find the single DECL of pointer type in the tree T and return it.
+   If there are zero or more than one such DECLs, return NULL.  */
+
+static tree
+find_single_pointer_decl (tree t)
+{
+  tree decl = NULL_TREE;
+
+  if (walk_tree (&t, find_single_pointer_decl_1, &decl, NULL))
+    {
+      /* find_single_pointer_decl_1 returns a non-zero value, causing
+	 walk_tree to return a non-zero value, to indicate that it
+	 found more than one pointer DECL.  */
+      return NULL_TREE;
+    }
+
+  return decl;
+}
+
 /* Create a new temporary name with PREFIX.  Returns an identifier.  */
 
 static GTY(()) unsigned int tmp_var_id_num;
@@ -470,6 +512,24 @@ internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
 
   t = lookup_tmp_var (val, is_formal);
 
+  if (is_formal)
+    {
+      tree u = find_single_pointer_decl (val);
+
+      if (u && TREE_CODE (u) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (u))
+	u = DECL_GET_RESTRICT_BASE (u);
+      if (u && TYPE_RESTRICT (TREE_TYPE (u)))
+	{
+	  if (DECL_BASED_ON_RESTRICT_P (t))
+	    gcc_assert (u == DECL_GET_RESTRICT_BASE (t));
+	  else
+	    {
+	      DECL_BASED_ON_RESTRICT_P (t) = 1;
+	      SET_DECL_RESTRICT_BASE (t, u);
+	    }
+	}
+    }
+
   if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE)
     DECL_COMPLEX_GIMPLE_REG_P (t) = 1;