Better typing and type verification

src/types-inl.h

 // Copyright 2014 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_TYPES_INL_H_
 #define V8_TYPES_INL_H_
 
 #include "src/types.h"
 
 #include "src/factory.h"
@@ skipping 38 matching lines @@
   }
   return this->Contains(value);
 }
 
 
 // -----------------------------------------------------------------------------
 // ZoneTypeConfig
 
 // static
 template<class T>
+T* ZoneTypeConfig::null_handle() {
+  return NULL;
+}
+
+
+// static
+template<class T>
 T* ZoneTypeConfig::handle(T* type) {
   return type;
 }
 
 
 // static
 template<class T>
 T* ZoneTypeConfig::cast(Type* type) {
   return static_cast<T*>(type);
 }
@@ skipping 123 matching lines @@
   DCHECK(0 <= i && i <= struct_length(structure));
   structure[2 + i] = x.location();
 }
 
 
 // -----------------------------------------------------------------------------
 // HeapTypeConfig
 
 // static
 template<class T>
+i::Handle<T> HeapTypeConfig::null_handle() {
+  return i::Handle<T>();
+}
+
+
+// static
+template<class T>
 i::Handle<T> HeapTypeConfig::handle(T* type) {
   return i::handle(type, i::HeapObject::cast(type)->GetIsolate());
 }
 
 
 // static
 template<class T>
 i::Handle<T> HeapTypeConfig::cast(i::Handle<Type> type) {
   return i::Handle<T>::cast(type);
 }
@@ skipping 118 matching lines @@
 // static
 template<class V>
 void HeapTypeConfig::struct_set_value(
     i::Handle<Struct> structure, int i, i::Handle<V> x) {
   structure->set(i + 1, *x);
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_TYPES_INL_H_