tree-ssa-ccp.c (visit_assignment): Verify that result of VIEW_CONVERT_EXPR is_gimple_min_invariant.

	* tree-ssa-ccp.c (visit_assignment): Verify that result of
	VIEW_CONVERT_EXPR is_gimple_min_invariant.

From-SVN: r95510

gcc/ChangeLog

 2005-02-24  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
 
+	* tree-ssa-ccp.c (visit_assignment): Verify that result of
+	VIEW_CONVERT_EXPR is_gimple_min_invariant.
+
 	* print-tree.c (print_node_brief): Print LABEL_DECL_UID.
 	(print_node): Likewise.
 	Print TYPE_SIZES_GIMPLIFIED.

gcc/tree-ssa-ccp.c

@@ -1060,9 +1060,7 @@ visit_assignment (tree stmt, tree *output_p)
       val = evaluate_stmt (stmt);
 
   /* If the original LHS was a VIEW_CONVERT_EXPR, modify the constant
-     value to be a VIEW_CONVERT_EXPR of the old constant value.  This is
-     valid because a VIEW_CONVERT_EXPR is valid everywhere an operand of
-     aggregate type is valid.
+     value to be a VIEW_CONVERT_EXPR of the old constant value.
 
      ??? Also, if this was a definition of a bitfield, we need to widen
      the constant value into the type of the destination variable.  This
@@ -1073,10 +1071,18 @@ visit_assignment (tree stmt, tree *output_p)
     if (TREE_CODE (orig_lhs) == VIEW_CONVERT_EXPR
 	&& val.lattice_val == CONSTANT)
       {
-	val.const_val = build1 (VIEW_CONVERT_EXPR,
-				TREE_TYPE (TREE_OPERAND (orig_lhs, 0)),
-				val.const_val);
+	tree w = fold (build1 (VIEW_CONVERT_EXPR,
+			       TREE_TYPE (TREE_OPERAND (orig_lhs, 0)),
+			       val.const_val));
+
 	orig_lhs = TREE_OPERAND (orig_lhs, 1);
+	if (w && is_gimple_min_invariant (w))
+	  val.const_val = w;
+	else
+	  {
+	    val.lattice_val = VARYING;
+	    val.const_val = NULL;
+	  }
       }
 
     if (val.lattice_val == CONSTANT