Better typing and type verification

src/compiler/node-properties-inl.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_NODE_PROPERTIES_INL_H_
 #define V8_COMPILER_NODE_PROPERTIES_INL_H_
 
 #include "src/v8.h"
 
 #include "src/compiler/common-operator.h"
@@ skipping 174 matching lines @@
     } else {
       iter = iter.UpdateToAndIncrement(value);
     }
   }
 }
 
 
 // -----------------------------------------------------------------------------
 // Type Bounds.
 
-inline Bounds NodeProperties::GetBounds(Node* node) { return node->bounds(); }
+inline bool NodeProperties::IsTyped(Node* node) {
+  Bounds bounds = node->bounds();
+  DCHECK((bounds.lower == NULL) == (bounds.upper == NULL));
+  return bounds.upper != NULL;
+}
+
+inline Bounds NodeProperties::GetBounds(Node* node) {
+  DCHECK(IsTyped(node));
+  return node->bounds();
+}
 
 inline void NodeProperties::SetBounds(Node* node, Bounds b) {
   node->set_bounds(b);
 }
 
 
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_NODE_PROPERTIES_INL_H_