Add flag to tracing element kind transitions

src/objects.h

 // Copyright 2011 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 155 matching lines @@
   // Derived constants from ElementsKind
   FIRST_EXTERNAL_ARRAY_ELEMENTS_KIND = EXTERNAL_BYTE_ELEMENTS,
   LAST_EXTERNAL_ARRAY_ELEMENTS_KIND = EXTERNAL_PIXEL_ELEMENTS,
   FIRST_ELEMENTS_KIND = FAST_SMI_ONLY_ELEMENTS,
   LAST_ELEMENTS_KIND = EXTERNAL_PIXEL_ELEMENTS
 };
 
 static const int kElementsKindCount =
     LAST_ELEMENTS_KIND - FIRST_ELEMENTS_KIND + 1;
 
+void PrintElementsKind(FILE* out, ElementsKind kind);
+
 // PropertyDetails captures type and attributes for a property.
 // They are used both in property dictionaries and instance descriptors.
 class PropertyDetails BASE_EMBEDDED {
  public:
   PropertyDetails(PropertyAttributes attributes,
                   PropertyType type,
                   int index = 0) {
     ASSERT(TypeField::is_valid(type));
     ASSERT(AttributesField::is_valid(attributes));
     ASSERT(StorageField::is_valid(index));
@@ skipping 664 matching lines @@
 // Since Smi and Failure are subclasses of Object no
 // data members can be present in Object.
 class Object : public MaybeObject {
  public:
   // Type testing.
 #define IS_TYPE_FUNCTION_DECL(type_)  inline bool Is##type_();
   OBJECT_TYPE_LIST(IS_TYPE_FUNCTION_DECL)
   HEAP_OBJECT_TYPE_LIST(IS_TYPE_FUNCTION_DECL)
 #undef IS_TYPE_FUNCTION_DECL
 
+  inline bool IsFixedArrayBase();
+
   // Returns true if this object is an instance of the specified
   // function template.
   inline bool IsInstanceOf(FunctionTemplateInfo* type);
 
   inline bool IsStruct();
 #define DECLARE_STRUCT_PREDICATE(NAME, Name, name) inline bool Is##Name();
   STRUCT_LIST(DECLARE_STRUCT_PREDICATE)
 #undef DECLARE_STRUCT_PREDICATE
 
   INLINE(bool IsSpecObject());
@@ skipping 1033 matching lines @@
     PrintProperties(stdout);
   }
   void PrintProperties(FILE* out);
 
   inline void PrintElements() {
     PrintElements(stdout);
   }
   void PrintElements(FILE* out);
 #endif
 
+  void PrintElementsTransition(
+      FILE* file, ElementsKind from_kind, FixedArrayBase* from_elements,
+      ElementsKind to_kind, FixedArrayBase* to_elements);
+
 #ifdef DEBUG
   // Structure for collecting spill information about JSObjects.
   class SpillInformation {
    public:
     void Clear();
     void Print();
     int number_of_objects_;
     int number_of_objects_with_fast_properties_;
     int number_of_objects_with_fast_elements_;
     int number_of_fast_used_fields_;
@@ skipping 5712 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_