Better typing and type verification

src/compiler/node-properties-inl.h

Index: src/compiler/node-properties-inl.h
diff --git a/src/compiler/node-properties-inl.h b/src/compiler/node-properties-inl.h
index bc52dfdb7519d6470a658e2729ab49ca7d32652c..72e031bb3b93e1b7f9cd33ea9f6ddd93dcd9d06b 100644
--- a/src/compiler/node-properties-inl.h
+++ b/src/compiler/node-properties-inl.h
@@ -192,7 +192,16 @@ inline void NodeProperties::ReplaceWithValue(Node* node, Node* 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);