Handlify JSObject::MigrateInstance and friends.

src/objects.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2154 matching lines @@
   // return value indicates whether the transition was successful.
   static inline Handle<Map> FindTransitionToField(Handle<Map> map,
                                                   Handle<Name> key);
 
   inline int LastAddedFieldIndex();
 
   // Extend the receiver with a single fast property appeared first in the
   // passed map. This also extends the property backing store if necessary.
   static void AllocateStorageForMap(Handle<JSObject> object, Handle<Map> map);
 
+  // Migrates the given object to a map whose field representations are the
+  // lowest upper bound of all known representations for that field.
   static void MigrateInstance(Handle<JSObject> instance);
 
+  // Migrates the given object only if the target map is already available,
+  // or returns an empty handle if such a map is not yet available.
   static Handle<Object> TryMigrateInstance(Handle<JSObject> instance);
-  inline MUST_USE_RESULT MaybeObject* TryMigrateInstance();
 
   // Can cause GC.
   MUST_USE_RESULT MaybeObject* SetLocalPropertyIgnoreAttributesTrampoline(
       Name* key,
       Object* value,
       PropertyAttributes attributes,
       ValueType value_type = OPTIMAL_REPRESENTATION,
       StoreMode mode = ALLOW_AS_CONSTANT,
       ExtensibilityCheck extensibility_check = PERFORM_EXTENSIBILITY_CHECK);
 
@@ skipping 273 matching lines @@
       ElementsKind elements_kind);
   MUST_USE_RESULT MaybeObject* GetElementsTransitionMapSlow(
       ElementsKind elements_kind);
 
   static void TransitionElementsKind(Handle<JSObject> object,
                                      ElementsKind to_kind);
 
   MUST_USE_RESULT MaybeObject* TransitionElementsKind(ElementsKind to_kind);
   MUST_USE_RESULT MaybeObject* UpdateAllocationSite(ElementsKind to_kind);
 
+  // TODO(mstarzinger): Both public because of ConvertAnsSetLocalProperty().
   static void MigrateToMap(Handle<JSObject> object, Handle<Map> new_map);
-  MUST_USE_RESULT MaybeObject* MigrateToMap(Map* new_map);
   static void GeneralizeFieldRepresentation(Handle<JSObject> object,
                                             int modify_index,
                                             Representation new_representation,
                                             StoreMode store_mode);
 
   // Convert the object to use the canonical dictionary
   // representation. If the object is expected to have additional properties
   // added this number can be indicated to have the backing store allocated to
   // an initial capacity for holding these properties.
   static void NormalizeProperties(Handle<JSObject> object,
@@ skipping 7757 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_