v8.h

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// 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
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#ifndef V8_H_
#define V8_H_

#include "v8stdint.h"

// We reserve the V8_* prefix for macros defined in V8 public API and
// assume there are no name conflicts with the embedder's code.

#ifdef V8_OS_WIN

// Setup for Windows DLL export/import. When building the V8 DLL the
// BUILDING_V8_SHARED needs to be defined. When building a program which uses
// the V8 DLL USING_V8_SHARED needs to be defined. When either building the V8
// static library or building a program which uses the V8 static library neither
// BUILDING_V8_SHARED nor USING_V8_SHARED should be defined.
#if defined(BUILDING_V8_SHARED) && defined(USING_V8_SHARED)
#error both BUILDING_V8_SHARED and USING_V8_SHARED are set - please check the\
  build configuration to ensure that at most one of these is set
#endif

#ifdef BUILDING_V8_SHARED
# define V8_EXPORT __declspec(dllexport)
#elif USING_V8_SHARED
# define V8_EXPORT __declspec(dllimport)
#else
# define V8_EXPORT
#endif  // BUILDING_V8_SHARED

#else  // V8_OS_WIN

// Setup for Linux shared library export.
#if V8_HAS_ATTRIBUTE_VISIBILITY && defined(V8_SHARED)
# ifdef BUILDING_V8_SHARED
#  define V8_EXPORT __attribute__ ((visibility("default")))
# else
#  define V8_EXPORT
# endif
#else
# define V8_EXPORT
#endif

#endif  // V8_OS_WIN

namespace v8 {

class AccessorSignature;
class Array;
class Boolean;
class BooleanObject;
class Context;
class CpuProfiler;
class Data;
class Date;
class DeclaredAccessorDescriptor;
class External;
class Function;
class FunctionTemplate;
class HeapProfiler;
class ImplementationUtilities;
class Int32;
class Integer;
class Isolate;
class Number;
class NumberObject;
class Object;
class ObjectOperationDescriptor;
class ObjectTemplate;
class Platform;
class Primitive;
class RawOperationDescriptor;
class Script;
class Signature;
class StackFrame;
class StackTrace;
class String;
class StringObject;
class Symbol;
class SymbolObject;
class Private;
class Uint32;
class Utils;
class Value;
template <class T> class Handle;
template <class T> class Local;
template <class T> class Eternal;
template<class T> class NonCopyablePersistentTraits;
template<class T> class PersistentBase;
template<class T,
         class M = NonCopyablePersistentTraits<T> > class Persistent;
template<class T> class UniquePersistent;
template<class K, class V, class T> class PersistentValueMap;
template<class T, class P> class WeakCallbackObject;
class FunctionTemplate;
class ObjectTemplate;
class Data;
template<typename T> class FunctionCallbackInfo;
template<typename T> class PropertyCallbackInfo;
class StackTrace;
class StackFrame;
class Isolate;
class DeclaredAccessorDescriptor;
class ObjectOperationDescriptor;
class RawOperationDescriptor;
class CallHandlerHelper;
class EscapableHandleScope;
template<typename T> class ReturnValue;

namespace internal {
class Arguments;
class Heap;
class HeapObject;
class Isolate;
class Object;
template<typename T> class CustomArguments;
class PropertyCallbackArguments;
class FunctionCallbackArguments;
class GlobalHandles;
}


class UniqueId {
 public:
  explicit UniqueId(intptr_t data)
      : data_(data) {}

  bool operator==(const UniqueId& other) const {
    return data_ == other.data_;
  }

  bool operator!=(const UniqueId& other) const {
    return data_ != other.data_;
  }

  bool operator<(const UniqueId& other) const {
    return data_ < other.data_;
  }

 private:
  intptr_t data_;
};

// --- Handles ---

#define TYPE_CHECK(T, S)                                       \
  while (false) {                                              \
    *(static_cast<T* volatile*>(0)) = static_cast<S*>(0);      \
  }


template <class T> class Handle {
 public:
  V8_INLINE Handle() : val_(0) {}

  template <class S> V8_INLINE Handle(Handle<S> that)
      : val_(reinterpret_cast<T*>(*that)) {
    TYPE_CHECK(T, S);
  }

  V8_INLINE bool IsEmpty() const { return val_ == 0; }

  V8_INLINE void Clear() { val_ = 0; }

  V8_INLINE T* operator->() const { return val_; }

  V8_INLINE T* operator*() const { return val_; }

  template <class S> V8_INLINE bool operator==(const Handle<S>& that) const {
    internal::Object** a = reinterpret_cast<internal::Object**>(this->val_);
    internal::Object** b = reinterpret_cast<internal::Object**>(that.val_);
    if (a == 0) return b == 0;
    if (b == 0) return false;
    return *a == *b;
  }

  template <class S> V8_INLINE bool operator==(
      const PersistentBase<S>& that) const {
    internal::Object** a = reinterpret_cast<internal::Object**>(this->val_);
    internal::Object** b = reinterpret_cast<internal::Object**>(that.val_);
    if (a == 0) return b == 0;
    if (b == 0) return false;
    return *a == *b;
  }

  template <class S> V8_INLINE bool operator!=(const Handle<S>& that) const {
    return !operator==(that);
  }

  template <class S> V8_INLINE bool operator!=(
      const Persistent<S>& that) const {
    return !operator==(that);
  }

  template <class S> V8_INLINE static Handle<T> Cast(Handle<S> that) {
#ifdef V8_ENABLE_CHECKS
    // If we're going to perform the type check then we have to check
    // that the handle isn't empty before doing the checked cast.
    if (that.IsEmpty()) return Handle<T>();
#endif
    return Handle<T>(T::Cast(*that));
  }

  template <class S> V8_INLINE Handle<S> As() {
    return Handle<S>::Cast(*this);
  }

  V8_INLINE static Handle<T> New(Isolate* isolate, Handle<T> that) {
    return New(isolate, that.val_);
  }
  V8_INLINE static Handle<T> New(Isolate* isolate,
                                 const PersistentBase<T>& that) {
    return New(isolate, that.val_);
  }

#ifndef V8_ALLOW_ACCESS_TO_RAW_HANDLE_CONSTRUCTOR

 private:
#endif

  V8_INLINE explicit Handle(T* val) : val_(val) {}

 private:
  friend class Utils;
  template<class F, class M> friend class Persistent;
  template<class F> friend class PersistentBase;
  template<class F> friend class Handle;
  template<class F> friend class Local;
  template<class F> friend class FunctionCallbackInfo;
  template<class F> friend class PropertyCallbackInfo;
  template<class F> friend class internal::CustomArguments;
  friend Handle<Primitive> Undefined(Isolate* isolate);
  friend Handle<Primitive> Null(Isolate* isolate);
  friend Handle<Boolean> True(Isolate* isolate);
  friend Handle<Boolean> False(Isolate* isolate);
  friend class Context;
  friend class HandleScope;
  friend class Object;
  friend class Private;

  V8_INLINE static Handle<T> New(Isolate* isolate, T* that);

  T* val_;
};


template <class T> class Local : public Handle<T> {
 public:
  V8_INLINE Local();
  template <class S> V8_INLINE Local(Local<S> that)
      : Handle<T>(reinterpret_cast<T*>(*that)) {
    TYPE_CHECK(T, S);
  }


  template <class S> V8_INLINE static Local<T> Cast(Local<S> that) {
#ifdef V8_ENABLE_CHECKS
    // If we're going to perform the type check then we have to check
    // that the handle isn't empty before doing the checked cast.
    if (that.IsEmpty()) return Local<T>();
#endif
    return Local<T>(T::Cast(*that));
  }
  template <class S> V8_INLINE Local(Handle<S> that)
      : Handle<T>(reinterpret_cast<T*>(*that)) {
    TYPE_CHECK(T, S);
  }

  template <class S> V8_INLINE Local<S> As() {
    return Local<S>::Cast(*this);
  }

  V8_INLINE static Local<T> New(Isolate* isolate, Handle<T> that);
  V8_INLINE static Local<T> New(Isolate* isolate,
                                const PersistentBase<T>& that);

#ifndef V8_ALLOW_ACCESS_TO_RAW_HANDLE_CONSTRUCTOR

 private:
#endif
  template <class S> V8_INLINE Local(S* that) : Handle<T>(that) { }

 private:
  friend class Utils;
  template<class F> friend class Eternal;
  template<class F> friend class PersistentBase;
  template<class F, class M> friend class Persistent;
  template<class F> friend class Handle;
  template<class F> friend class Local;
  template<class F> friend class FunctionCallbackInfo;
  template<class F> friend class PropertyCallbackInfo;
  friend class String;
  friend class Object;
  friend class Context;
  template<class F> friend class internal::CustomArguments;
  friend class HandleScope;
  friend class EscapableHandleScope;
  template<class F1, class F2, class F3> friend class PersistentValueMap;

  V8_INLINE static Local<T> New(Isolate* isolate, T* that);
};


// Eternal handles are set-once handles that live for the life of the isolate.
template <class T> class Eternal {
 public:
  V8_INLINE Eternal() : index_(kInitialValue) { }
  template<class S>
  V8_INLINE Eternal(Isolate* isolate, Local<S> handle) : index_(kInitialValue) {
    Set(isolate, handle);
  }
  // Can only be safely called if already set.
  V8_INLINE Local<T> Get(Isolate* isolate);
  V8_INLINE bool IsEmpty() { return index_ == kInitialValue; }
  template<class S> V8_INLINE void Set(Isolate* isolate, Local<S> handle);

 private:
  static const int kInitialValue = -1;
  int index_;
};


template<class T, class P>
class WeakCallbackData {
 public:
  typedef void (*Callback)(const WeakCallbackData<T, P>& data);

  V8_INLINE Isolate* GetIsolate() const { return isolate_; }
  V8_INLINE Local<T> GetValue() const { return handle_; }
  V8_INLINE P* GetParameter() const { return parameter_; }

 private:
  friend class internal::GlobalHandles;
  WeakCallbackData(Isolate* isolate, Local<T> handle, P* parameter)
    : isolate_(isolate), handle_(handle), parameter_(parameter) { }
  Isolate* isolate_;
  Local<T> handle_;
  P* parameter_;
};


template <class T> class PersistentBase {
 public:
  V8_INLINE void Reset();
  template <class S>
  V8_INLINE void Reset(Isolate* isolate, const Handle<S>& other);

  template <class S>
  V8_INLINE void Reset(Isolate* isolate, const PersistentBase<S>& other);

  V8_INLINE bool IsEmpty() const { return val_ == 0; }

  template <class S>
  V8_INLINE bool operator==(const PersistentBase<S>& that) const {
    internal::Object** a = reinterpret_cast<internal::Object**>(this->val_);
    internal::Object** b = reinterpret_cast<internal::Object**>(that.val_);
    if (a == 0) return b == 0;
    if (b == 0) return false;
    return *a == *b;
  }

  template <class S> V8_INLINE bool operator==(const Handle<S>& that) const {
    internal::Object** a = reinterpret_cast<internal::Object**>(this->val_);
    internal::Object** b = reinterpret_cast<internal::Object**>(that.val_);
    if (a == 0) return b == 0;
    if (b == 0) return false;
    return *a == *b;
  }

  template <class S>
  V8_INLINE bool operator!=(const PersistentBase<S>& that) const {
    return !operator==(that);
  }

  template <class S> V8_INLINE bool operator!=(const Handle<S>& that) const {
    return !operator==(that);
  }

  template<typename P>
  V8_INLINE void SetWeak(
      P* parameter,
      typename WeakCallbackData<T, P>::Callback callback);

  template<typename S, typename P>
  V8_INLINE void SetWeak(
      P* parameter,
      typename WeakCallbackData<S, P>::Callback callback);

  template<typename P>
  V8_INLINE P* ClearWeak();

  // TODO(dcarney): remove this.
  V8_INLINE void ClearWeak() { ClearWeak<void>(); }

  V8_INLINE void MarkIndependent();

  V8_INLINE void MarkPartiallyDependent();

  V8_INLINE bool IsIndependent() const;

  V8_INLINE bool IsNearDeath() const;

  V8_INLINE bool IsWeak() const;

  V8_INLINE void SetWrapperClassId(uint16_t class_id);

  V8_INLINE uint16_t WrapperClassId() const;

 private:
  friend class Isolate;
  friend class Utils;
  template<class F> friend class Handle;
  template<class F> friend class Local;
  template<class F1, class F2> friend class Persistent;
  template<class F> friend class UniquePersistent;
  template<class F> friend class PersistentBase;
  template<class F> friend class ReturnValue;
  template<class F1, class F2, class F3> friend class PersistentValueMap;
  friend class Object;

  explicit V8_INLINE PersistentBase(T* val) : val_(val) {}
  PersistentBase(PersistentBase& other); // NOLINT
  void operator=(PersistentBase&);
  V8_INLINE static T* New(Isolate* isolate, T* that);

  T* val_;
};


template<class T>
class NonCopyablePersistentTraits {
 public:
  typedef Persistent<T, NonCopyablePersistentTraits<T> > NonCopyablePersistent;
  static const bool kResetInDestructor = false;
  template<class S, class M>
  V8_INLINE static void Copy(const Persistent<S, M>& source,
                             NonCopyablePersistent* dest) {
    Uncompilable<Object>();
  }
  // TODO(dcarney): come up with a good compile error here.
  template<class O> V8_INLINE static void Uncompilable() {
    TYPE_CHECK(O, Primitive);
  }
};


template<class T>
struct CopyablePersistentTraits {
  typedef Persistent<T, CopyablePersistentTraits<T> > CopyablePersistent;
  static const bool kResetInDestructor = true;
  template<class S, class M>
  static V8_INLINE void Copy(const Persistent<S, M>& source,
                             CopyablePersistent* dest) {
    // do nothing, just allow copy
  }
};


template <class T, class M> class Persistent : public PersistentBase<T> {
 public:
  V8_INLINE Persistent() : PersistentBase<T>(0) { }
  template <class S> V8_INLINE Persistent(Isolate* isolate, Handle<S> that)
      : PersistentBase<T>(PersistentBase<T>::New(isolate, *that)) {
    TYPE_CHECK(T, S);
  }
  template <class S, class M2>
  V8_INLINE Persistent(Isolate* isolate, const Persistent<S, M2>& that)
    : PersistentBase<T>(PersistentBase<T>::New(isolate, *that)) {
    TYPE_CHECK(T, S);
  }
  V8_INLINE Persistent(const Persistent& that) : PersistentBase<T>(0) {
    Copy(that);
  }
  template <class S, class M2>
  V8_INLINE Persistent(const Persistent<S, M2>& that) : PersistentBase<T>(0) {
    Copy(that);
  }
  V8_INLINE Persistent& operator=(const Persistent& that) { // NOLINT
    Copy(that);
    return *this;
  }
  template <class S, class M2>
  V8_INLINE Persistent& operator=(const Persistent<S, M2>& that) { // NOLINT
    Copy(that);
    return *this;
  }
  V8_INLINE ~Persistent() {
    if (M::kResetInDestructor) this->Reset();
  }

  // TODO(dcarney): this is pretty useless, fix or remove
  template <class S>
  V8_INLINE static Persistent<T>& Cast(Persistent<S>& that) { // NOLINT
#ifdef V8_ENABLE_CHECKS
    // If we're going to perform the type check then we have to check
    // that the handle isn't empty before doing the checked cast.
    if (!that.IsEmpty()) T::Cast(*that);
#endif
    return reinterpret_cast<Persistent<T>&>(that);
  }

  // TODO(dcarney): this is pretty useless, fix or remove
  template <class S> V8_INLINE Persistent<S>& As() { // NOLINT
    return Persistent<S>::Cast(*this);
  }

  // This will be removed.
  V8_INLINE T* ClearAndLeak();

  // TODO(dcarney): remove
#ifndef V8_ALLOW_ACCESS_TO_RAW_HANDLE_CONSTRUCTOR

 private:
#endif
  template <class S> V8_INLINE Persistent(S* that) : PersistentBase<T>(that) { }

  V8_INLINE T* operator*() const { return this->val_; }

 private:
  friend class Isolate;
  friend class Utils;
  template<class F> friend class Handle;
  template<class F> friend class Local;
  template<class F1, class F2> friend class Persistent;
  template<class F> friend class ReturnValue;

  template<class S, class M2>
  V8_INLINE void Copy(const Persistent<S, M2>& that);
};


template<class T>
class UniquePersistent : public PersistentBase<T> {
  struct RValue {
    V8_INLINE explicit RValue(UniquePersistent* obj) : object(obj) {}
    UniquePersistent* object;
  };

 public:
  V8_INLINE UniquePersistent() : PersistentBase<T>(0) { }
  template <class S>
  V8_INLINE UniquePersistent(Isolate* isolate, Handle<S> that)
      : PersistentBase<T>(PersistentBase<T>::New(isolate, *that)) {
    TYPE_CHECK(T, S);
  }
  template <class S>
  V8_INLINE UniquePersistent(Isolate* isolate, const PersistentBase<S>& that)
    : PersistentBase<T>(PersistentBase<T>::New(isolate, that.val_)) {
    TYPE_CHECK(T, S);
  }
  V8_INLINE UniquePersistent(RValue rvalue)
    : PersistentBase<T>(rvalue.object->val_) {
    rvalue.object->val_ = 0;
  }
  V8_INLINE ~UniquePersistent() { this->Reset(); }
  template<class S>
  V8_INLINE UniquePersistent& operator=(UniquePersistent<S> rhs) {
    TYPE_CHECK(T, S);
    this->Reset();
    this->val_ = rhs.val_;
    rhs.val_ = 0;
    return *this;
  }
  V8_INLINE operator RValue() { return RValue(this); }
  V8_INLINE UniquePersistent Pass() { return UniquePersistent(RValue(this)); }

 private:
  UniquePersistent(UniquePersistent&);
  void operator=(UniquePersistent&);
};


class V8_EXPORT HandleScope {
 public:
  HandleScope(Isolate* isolate);

  ~HandleScope();

  static int NumberOfHandles(Isolate* isolate);

  V8_INLINE Isolate* GetIsolate() const {
    return reinterpret_cast<Isolate*>(isolate_);
  }

 protected:
  V8_INLINE HandleScope() {}

  void Initialize(Isolate* isolate);

  static internal::Object** CreateHandle(internal::Isolate* isolate,
                                         internal::Object* value);

 private:
  // Uses heap_object to obtain the current Isolate.
  static internal::Object** CreateHandle(internal::HeapObject* heap_object,
                                         internal::Object* value);

  // Make it hard to create heap-allocated or illegal handle scopes by
  // disallowing certain operations.
  HandleScope(const HandleScope&);
  void operator=(const HandleScope&);
  void* operator new(size_t size);
  void operator delete(void*, size_t);

  internal::Isolate* isolate_;
  internal::Object** prev_next_;
  internal::Object** prev_limit_;

  // Local::New uses CreateHandle with an Isolate* parameter.
  template<class F> friend class Local;

  // Object::GetInternalField and Context::GetEmbedderData use CreateHandle with
  // a HeapObject* in their shortcuts.
  friend class Object;
  friend class Context;
};


class V8_EXPORT EscapableHandleScope : public HandleScope {
 public:
  EscapableHandleScope(Isolate* isolate);
  V8_INLINE ~EscapableHandleScope() {}

  template <class T>
  V8_INLINE Local<T> Escape(Local<T> value) {
    internal::Object** slot =
        Escape(reinterpret_cast<internal::Object**>(*value));
    return Local<T>(reinterpret_cast<T*>(slot));
  }

 private:
  internal::Object** Escape(internal::Object** escape_value);

  // Make it hard to create heap-allocated or illegal handle scopes by
  // disallowing certain operations.
  EscapableHandleScope(const EscapableHandleScope&);
  void operator=(const EscapableHandleScope&);
  void* operator new(size_t size);
  void operator delete(void*, size_t);

  internal::Object** escape_slot_;
};


template<class T>
struct Maybe {
  Maybe() : has_value(false) {}
  explicit Maybe(T t) : has_value(true), value(t) {}
  Maybe(bool has, T t) : has_value(has), value(t) {}

  bool has_value;
  T value;
};


// --- Special objects ---


class V8_EXPORT Data {
 private:
  Data();
};


class V8_EXPORT ScriptData {  // NOLINT
 public:
  virtual ~ScriptData() { }

  static ScriptData* PreCompile(Handle<String> source);

  static ScriptData* New(const char* data, int length);

  virtual int Length() = 0;

  virtual const char* Data() = 0;

  virtual bool HasError() = 0;
};


class ScriptOrigin {
 public:
  V8_INLINE ScriptOrigin(
      Handle<Value> resource_name,
      Handle<Integer> resource_line_offset = Handle<Integer>(),
      Handle<Integer> resource_column_offset = Handle<Integer>(),
      Handle<Boolean> resource_is_shared_cross_origin = Handle<Boolean>())
      : resource_name_(resource_name),
        resource_line_offset_(resource_line_offset),
        resource_column_offset_(resource_column_offset),
        resource_is_shared_cross_origin_(resource_is_shared_cross_origin) { }
  V8_INLINE Handle<Value> ResourceName() const;
  V8_INLINE Handle<Integer> ResourceLineOffset() const;
  V8_INLINE Handle<Integer> ResourceColumnOffset() const;
  V8_INLINE Handle<Boolean> ResourceIsSharedCrossOrigin() const;
 private:
  Handle<Value> resource_name_;
  Handle<Integer> resource_line_offset_;
  Handle<Integer> resource_column_offset_;
  Handle<Boolean> resource_is_shared_cross_origin_;
};


class V8_EXPORT UnboundScript {
 public:
  Local<Script> BindToCurrentContext();

  int GetId();
  Handle<Value> GetScriptName();

  int GetLineNumber(int code_pos);

  static const int kNoScriptId = 0;
};


class V8_EXPORT Script {
 public:
  static Local<Script> Compile(Handle<String> source,
                               ScriptOrigin* origin = NULL,
                               ScriptData* script_data = NULL);

  // To be decprecated, use the Compile above.
  static Local<Script> Compile(Handle<String> source,
                               Handle<String> file_name);

  Local<Value> Run();

  Local<UnboundScript> GetUnboundScript();

  // To be deprecated; use GetUnboundScript()->GetId();
  int GetId() {
    return GetUnboundScript()->GetId();
  }

  // Use GetUnboundScript()->GetId();
  V8_DEPRECATED("Use GetUnboundScript()->GetId()",
                Handle<Value> GetScriptName()) {
    return GetUnboundScript()->GetScriptName();
  }

  V8_DEPRECATED("Use GetUnboundScript()->GetLineNumber()",
                int GetLineNumber(int code_pos)) {
    return GetUnboundScript()->GetLineNumber(code_pos);
  }
};


class V8_EXPORT ScriptCompiler {
 public:
  struct V8_EXPORT CachedData {
    enum BufferPolicy {
      BufferNotOwned,
      BufferOwned
    };

    CachedData() : data(NULL), length(0), buffer_policy(BufferNotOwned) {}

    // If buffer_policy is BufferNotOwned, the caller keeps the ownership of
    // data and guarantees that it stays alive until the CachedData object is
    // destroyed. If the policy is BufferOwned, the given data will be deleted
    // (with delete[]) when the CachedData object is destroyed.
    CachedData(const uint8_t* data, int length,
               BufferPolicy buffer_policy = BufferNotOwned);
    ~CachedData();
    // TODO(marja): Async compilation; add constructors which take a callback
    // which will be called when V8 no longer needs the data.
    const uint8_t* data;
    int length;
    BufferPolicy buffer_policy;

  private:
     // Prevent copying. Not implemented.
     CachedData(const CachedData&);
     CachedData& operator=(const CachedData&);
  };

  class Source {
   public:
    // Source takes ownership of CachedData.
    V8_INLINE Source(Local<String> source_string, const ScriptOrigin& origin,
           CachedData* cached_data = NULL);
    V8_INLINE Source(Local<String> source_string,
                     CachedData* cached_data = NULL);
    V8_INLINE ~Source();

    // Ownership of the CachedData or its buffers is *not* transferred to the
    // caller. The CachedData object is alive as long as the Source object is
    // alive.
    V8_INLINE const CachedData* GetCachedData() const;

   private:
    friend class ScriptCompiler;
     // Prevent copying. Not implemented.
    Source(const Source&);
    Source& operator=(const Source&);

    Local<String> source_string;

    // Origin information
    Handle<Value> resource_name;
    Handle<Integer> resource_line_offset;
    Handle<Integer> resource_column_offset;
    Handle<Boolean> resource_is_shared_cross_origin;

    // Cached data from previous compilation (if any), or generated during
    // compilation (if the generate_cached_data flag is passed to
    // ScriptCompiler).
    CachedData* cached_data;
  };

  enum CompileOptions {
    kNoCompileOptions,
    kProduceDataToCache = 1 << 0
  };

  static Local<UnboundScript> CompileUnbound(
      Isolate* isolate, Source* source,
      CompileOptions options = kNoCompileOptions);

  static Local<Script> Compile(
      Isolate* isolate, Source* source,
      CompileOptions options = kNoCompileOptions);
};


class V8_EXPORT Message {
 public:
  Local<String> Get() const;
  Local<String> GetSourceLine() const;

  Handle<Value> GetScriptResourceName() const;

  Handle<Value> GetScriptData() const;

  Handle<StackTrace> GetStackTrace() const;

  int GetLineNumber() const;

  int GetStartPosition() const;

  int GetEndPosition() const;

  int GetStartColumn() const;

  int GetEndColumn() const;

  bool IsSharedCrossOrigin() const;

  // TODO(1245381): Print to a string instead of on a FILE.
  static void PrintCurrentStackTrace(Isolate* isolate, FILE* out);

  static const int kNoLineNumberInfo = 0;
  static const int kNoColumnInfo = 0;
  static const int kNoScriptIdInfo = 0;
};


class V8_EXPORT StackTrace {
 public:
  enum StackTraceOptions {
    kLineNumber = 1,
    kColumnOffset = 1 << 1 | kLineNumber,
    kScriptName = 1 << 2,
    kFunctionName = 1 << 3,
    kIsEval = 1 << 4,
    kIsConstructor = 1 << 5,
    kScriptNameOrSourceURL = 1 << 6,
    kScriptId = 1 << 7,
    kOverview = kLineNumber | kColumnOffset | kScriptName | kFunctionName,
    kDetailed = kOverview | kIsEval | kIsConstructor | kScriptNameOrSourceURL
  };

  Local<StackFrame> GetFrame(uint32_t index) const;

  int GetFrameCount() const;

  Local<Array> AsArray();

  static Local<StackTrace> CurrentStackTrace(
      Isolate* isolate,
      int frame_limit,
      StackTraceOptions options = kOverview);
};


class V8_EXPORT StackFrame {
 public:
  int GetLineNumber() const;

  int GetColumn() const;

  int GetScriptId() const;

  Local<String> GetScriptName() const;

  Local<String> GetScriptNameOrSourceURL() const;

  Local<String> GetFunctionName() const;

  bool IsEval() const;

  bool IsConstructor() const;
};


class V8_EXPORT JSON {
 public:
  static Local<Value> Parse(Local<String> json_string);
};


// --- Value ---


class V8_EXPORT Value : public Data {
 public:
  V8_INLINE bool IsUndefined() const;

  V8_INLINE bool IsNull() const;

  bool IsTrue() const;

  bool IsFalse() const;

  V8_INLINE bool IsString() const;

  bool IsSymbol() const;

  bool IsFunction() const;

  bool IsArray() const;

  bool IsObject() const;

  bool IsBoolean() const;

  bool IsNumber() const;

  bool IsExternal() const;

  bool IsInt32() const;

  bool IsUint32() const;

  bool IsDate() const;

  bool IsBooleanObject() const;

  bool IsNumberObject() const;

  bool IsStringObject() const;

  bool IsSymbolObject() const;

  bool IsNativeError() const;

  bool IsRegExp() const;

  bool IsPromise() const;

  bool IsArrayBuffer() const;

  bool IsArrayBufferView() const;

  bool IsTypedArray() const;

  bool IsUint8Array() const;

  bool IsUint8ClampedArray() const;

  bool IsInt8Array() const;

  bool IsUint16Array() const;

  bool IsInt16Array() const;

  bool IsUint32Array() const;

  bool IsInt32Array() const;

  bool IsFloat32Array() const;

  bool IsFloat64Array() const;

  bool IsDataView() const;

  Local<Boolean> ToBoolean() const;
  Local<Number> ToNumber() const;
  Local<String> ToString() const;
  Local<String> ToDetailString() const;
  Local<Object> ToObject() const;
  Local<Integer> ToInteger() const;
  Local<Uint32> ToUint32() const;
  Local<Int32> ToInt32() const;

  Local<Uint32> ToArrayIndex() const;

  bool BooleanValue() const;
  double NumberValue() const;
  int64_t IntegerValue() const;
  uint32_t Uint32Value() const;
  int32_t Int32Value() const;

  bool Equals(Handle<Value> that) const;
  bool StrictEquals(Handle<Value> that) const;
  bool SameValue(Handle<Value> that) const;

  template <class T> V8_INLINE static Value* Cast(T* value);

 private:
  V8_INLINE bool QuickIsUndefined() const;
  V8_INLINE bool QuickIsNull() const;
  V8_INLINE bool QuickIsString() const;
  bool FullIsUndefined() const;
  bool FullIsNull() const;
  bool FullIsString() const;
};


class V8_EXPORT Primitive : public Value { };


class V8_EXPORT Boolean : public Primitive {
 public:
  bool Value() const;
  V8_INLINE static Handle<Boolean> New(Isolate* isolate, bool value);
};


class V8_EXPORT String : public Primitive {
 public:
  enum Encoding {
    UNKNOWN_ENCODING = 0x1,
    TWO_BYTE_ENCODING = 0x0,
    ASCII_ENCODING = 0x4,
    ONE_BYTE_ENCODING = 0x4
  };
  int Length() const;

  int Utf8Length() const;

  bool IsOneByte() const;

  bool ContainsOnlyOneByte() const;

  enum WriteOptions {
    NO_OPTIONS = 0,
    HINT_MANY_WRITES_EXPECTED = 1,
    NO_NULL_TERMINATION = 2,
    PRESERVE_ASCII_NULL = 4,
    // Used by WriteUtf8 to replace orphan surrogate code units with the
    // unicode replacement character. Needs to be set to guarantee valid UTF-8
    // output.
    REPLACE_INVALID_UTF8 = 8
  };

  // 16-bit character codes.
  int Write(uint16_t* buffer,
            int start = 0,
            int length = -1,
            int options = NO_OPTIONS) const;
  // One byte characters.
  int WriteOneByte(uint8_t* buffer,
                   int start = 0,
                   int length = -1,
                   int options = NO_OPTIONS) const;
  // UTF-8 encoded characters.
  int WriteUtf8(char* buffer,
                int length = -1,
                int* nchars_ref = NULL,
                int options = NO_OPTIONS) const;

  V8_INLINE static v8::Local<v8::String> Empty(Isolate* isolate);

  bool IsExternal() const;

  bool IsExternalAscii() const;

  class V8_EXPORT ExternalStringResourceBase {  // NOLINT
   public:
    virtual ~ExternalStringResourceBase() {}

   protected:
    ExternalStringResourceBase() {}

    virtual void Dispose() { delete this; }

   private:
    // Disallow copying and assigning.
    ExternalStringResourceBase(const ExternalStringResourceBase&);
    void operator=(const ExternalStringResourceBase&);

    friend class v8::internal::Heap;
  };

  class V8_EXPORT ExternalStringResource
      : public ExternalStringResourceBase {
   public:
    virtual ~ExternalStringResource() {}

    virtual const uint16_t* data() const = 0;

    virtual size_t length() const = 0;

   protected:
    ExternalStringResource() {}
  };

  class V8_EXPORT ExternalAsciiStringResource
      : public ExternalStringResourceBase {
   public:
    virtual ~ExternalAsciiStringResource() {}
    virtual const char* data() const = 0;
    virtual size_t length() const = 0;
   protected:
    ExternalAsciiStringResource() {}
  };

  typedef ExternalAsciiStringResource ExternalOneByteStringResource;

  V8_INLINE ExternalStringResourceBase* GetExternalStringResourceBase(
      Encoding* encoding_out) const;

  V8_INLINE ExternalStringResource* GetExternalStringResource() const;

  const ExternalAsciiStringResource* GetExternalAsciiStringResource() const;

  V8_INLINE static String* Cast(v8::Value* obj);

  enum NewStringType {
    kNormalString, kInternalizedString, kUndetectableString
  };

  static Local<String> NewFromUtf8(Isolate* isolate,
                                  const char* data,
                                  NewStringType type = kNormalString,
                                  int length = -1);

  static Local<String> NewFromOneByte(
      Isolate* isolate,
      const uint8_t* data,
      NewStringType type = kNormalString,
      int length = -1);

  static Local<String> NewFromTwoByte(
      Isolate* isolate,
      const uint16_t* data,
      NewStringType type = kNormalString,
      int length = -1);

  static Local<String> Concat(Handle<String> left, Handle<String> right);

  static Local<String> NewExternal(Isolate* isolate,
                                   ExternalStringResource* resource);

  bool MakeExternal(ExternalStringResource* resource);

  static Local<String> NewExternal(Isolate* isolate,
                                   ExternalAsciiStringResource* resource);

  bool MakeExternal(ExternalAsciiStringResource* resource);

  bool CanMakeExternal();

  class V8_EXPORT Utf8Value {
   public:
    explicit Utf8Value(Handle<v8::Value> obj);
    ~Utf8Value();
    char* operator*() { return str_; }
    const char* operator*() const { return str_; }
    int length() const { return length_; }
   private:
    char* str_;
    int length_;

    // Disallow copying and assigning.
    Utf8Value(const Utf8Value&);
    void operator=(const Utf8Value&);
  };

  class V8_EXPORT Value {
   public:
    explicit Value(Handle<v8::Value> obj);
    ~Value();
    uint16_t* operator*() { return str_; }
    const uint16_t* operator*() const { return str_; }
    int length() const { return length_; }
   private:
    uint16_t* str_;
    int length_;

    // Disallow copying and assigning.
    Value(const Value&);
    void operator=(const Value&);
  };

 private:
  void VerifyExternalStringResourceBase(ExternalStringResourceBase* v,
                                        Encoding encoding) const;
  void VerifyExternalStringResource(ExternalStringResource* val) const;
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT Symbol : public Primitive {
 public:
  // Returns the print name string of the symbol, or undefined if none.
  Local<Value> Name() const;

  // Create a symbol. If name is not empty, it will be used as the description.
  static Local<Symbol> New(
      Isolate *isolate, Local<String> name = Local<String>());

  // Access global symbol registry.
  // Note that symbols created this way are never collected, so
  // they should only be used for statically fixed properties.
  // Also, there is only one global name space for the names used as keys.
  // To minimize the potential for clashes, use qualified names as keys.
  static Local<Symbol> For(Isolate *isolate, Local<String> name);

  // Retrieve a global symbol. Similar to |For|, but using a separate
  // registry that is not accessible by (and cannot clash with) JavaScript code.
  static Local<Symbol> ForApi(Isolate *isolate, Local<String> name);

  V8_INLINE static Symbol* Cast(v8::Value* obj);
 private:
  Symbol();
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT Private : public Data {
 public:
  // Returns the print name string of the private symbol, or undefined if none.
  Local<Value> Name() const;

  // Create a private symbol. If name is not empty, it will be the description.
  static Local<Private> New(
      Isolate *isolate, Local<String> name = Local<String>());

  // Retrieve a global private symbol. If a symbol with this name has not
  // been retrieved in the same isolate before, it is created.
  // Note that private symbols created this way are never collected, so
  // they should only be used for statically fixed properties.
  // Also, there is only one global name space for the names used as keys.
  // To minimize the potential for clashes, use qualified names as keys,
  // e.g., "Class#property".
  static Local<Private> ForApi(Isolate *isolate, Local<String> name);

 private:
  Private();
};


class V8_EXPORT Number : public Primitive {
 public:
  double Value() const;
  static Local<Number> New(Isolate* isolate, double value);
  V8_INLINE static Number* Cast(v8::Value* obj);
 private:
  Number();
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT Integer : public Number {
 public:
  static Local<Integer> New(Isolate* isolate, int32_t value);
  static Local<Integer> NewFromUnsigned(Isolate* isolate, uint32_t value);
  int64_t Value() const;
  V8_INLINE static Integer* Cast(v8::Value* obj);
 private:
  Integer();
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT Int32 : public Integer {
 public:
  int32_t Value() const;
 private:
  Int32();
};


class V8_EXPORT Uint32 : public Integer {
 public:
  uint32_t Value() const;
 private:
  Uint32();
};


enum PropertyAttribute {
  None       = 0,
  ReadOnly   = 1 << 0,
  DontEnum   = 1 << 1,
  DontDelete = 1 << 2
};

enum ExternalArrayType {
  kExternalInt8Array = 1,
  kExternalUint8Array,
  kExternalInt16Array,
  kExternalUint16Array,
  kExternalInt32Array,
  kExternalUint32Array,
  kExternalFloat32Array,
  kExternalFloat64Array,
  kExternalUint8ClampedArray,

  // Legacy constant names
  kExternalByteArray = kExternalInt8Array,
  kExternalUnsignedByteArray = kExternalUint8Array,
  kExternalShortArray = kExternalInt16Array,
  kExternalUnsignedShortArray = kExternalUint16Array,
  kExternalIntArray = kExternalInt32Array,
  kExternalUnsignedIntArray = kExternalUint32Array,
  kExternalFloatArray = kExternalFloat32Array,
  kExternalDoubleArray = kExternalFloat64Array,
  kExternalPixelArray = kExternalUint8ClampedArray
};

typedef void (*AccessorGetterCallback)(
    Local<String> property,
    const PropertyCallbackInfo<Value>& info);


typedef void (*AccessorSetterCallback)(
    Local<String> property,
    Local<Value> value,
    const PropertyCallbackInfo<void>& info);


enum AccessControl {
  DEFAULT               = 0,
  ALL_CAN_READ          = 1,
  ALL_CAN_WRITE         = 1 << 1,
  PROHIBITS_OVERWRITING = 1 << 2
};


class V8_EXPORT Object : public Value {
 public:
  bool Set(Handle<Value> key,
           Handle<Value> value,
           PropertyAttribute attribs = None);

  bool Set(uint32_t index, Handle<Value> value);

  // Sets a local property on this object bypassing interceptors and
  // overriding accessors or read-only properties.
  //
  // Note that if the object has an interceptor the property will be set
  // locally, but since the interceptor takes precedence the local property
  // will only be returned if the interceptor doesn't return a value.
  //
  // Note also that this only works for named properties.
  bool ForceSet(Handle<Value> key,
                Handle<Value> value,
                PropertyAttribute attribs = None);

  Local<Value> Get(Handle<Value> key);

  Local<Value> Get(uint32_t index);

  PropertyAttribute GetPropertyAttributes(Handle<Value> key);

  bool Has(Handle<Value> key);

  bool Delete(Handle<Value> key);

  // Delete a property on this object bypassing interceptors and
  // ignoring dont-delete attributes.
  bool ForceDelete(Handle<Value> key);

  bool Has(uint32_t index);

  bool Delete(uint32_t index);

  bool SetAccessor(Handle<String> name,
                   AccessorGetterCallback getter,
                   AccessorSetterCallback setter = 0,
                   Handle<Value> data = Handle<Value>(),
                   AccessControl settings = DEFAULT,
                   PropertyAttribute attribute = None);

  // This function is not yet stable and should not be used at this time.
  bool SetDeclaredAccessor(Local<String> name,
                           Local<DeclaredAccessorDescriptor> descriptor,
                           PropertyAttribute attribute = None,
                           AccessControl settings = DEFAULT);

  void SetAccessorProperty(Local<String> name,
                           Local<Function> getter,
                           Handle<Function> setter = Handle<Function>(),
                           PropertyAttribute attribute = None,
                           AccessControl settings = DEFAULT);

  bool HasPrivate(Handle<Private> key);
  bool SetPrivate(Handle<Private> key, Handle<Value> value);
  bool DeletePrivate(Handle<Private> key);
  Local<Value> GetPrivate(Handle<Private> key);

  Local<Array> GetPropertyNames();

  Local<Array> GetOwnPropertyNames();

  Local<Value> GetPrototype();

  bool SetPrototype(Handle<Value> prototype);

  Local<Object> FindInstanceInPrototypeChain(Handle<FunctionTemplate> tmpl);

  Local<String> ObjectProtoToString();

  Local<Value> GetConstructor();

  Local<String> GetConstructorName();

  int InternalFieldCount();

  V8_INLINE static int InternalFieldCount(
      const PersistentBase<Object>& object) {
    return object.val_->InternalFieldCount();
  }

  V8_INLINE Local<Value> GetInternalField(int index);

  void SetInternalField(int index, Handle<Value> value);

  V8_INLINE void* GetAlignedPointerFromInternalField(int index);

  V8_INLINE static void* GetAlignedPointerFromInternalField(
      const PersistentBase<Object>& object, int index) {
    return object.val_->GetAlignedPointerFromInternalField(index);
  }

  void SetAlignedPointerInInternalField(int index, void* value);

  // Testers for local properties.
  bool HasOwnProperty(Handle<String> key);
  bool HasRealNamedProperty(Handle<String> key);
  bool HasRealIndexedProperty(uint32_t index);
  bool HasRealNamedCallbackProperty(Handle<String> key);

  Local<Value> GetRealNamedPropertyInPrototypeChain(Handle<String> key);

  Local<Value> GetRealNamedProperty(Handle<String> key);

  bool HasNamedLookupInterceptor();

  bool HasIndexedLookupInterceptor();

  void TurnOnAccessCheck();

  int GetIdentityHash();

  bool SetHiddenValue(Handle<String> key, Handle<Value> value);
  Local<Value> GetHiddenValue(Handle<String> key);
  bool DeleteHiddenValue(Handle<String> key);

  bool IsDirty();

  Local<Object> Clone();

  Local<Context> CreationContext();

  void SetIndexedPropertiesToPixelData(uint8_t* data, int length);
  bool HasIndexedPropertiesInPixelData();
  uint8_t* GetIndexedPropertiesPixelData();
  int GetIndexedPropertiesPixelDataLength();

  void SetIndexedPropertiesToExternalArrayData(void* data,
                                               ExternalArrayType array_type,
                                               int number_of_elements);
  bool HasIndexedPropertiesInExternalArrayData();
  void* GetIndexedPropertiesExternalArrayData();
  ExternalArrayType GetIndexedPropertiesExternalArrayDataType();
  int GetIndexedPropertiesExternalArrayDataLength();

  bool IsCallable();

  Local<Value> CallAsFunction(Handle<Value> recv,
                              int argc,
                              Handle<Value> argv[]);

  Local<Value> CallAsConstructor(int argc, Handle<Value> argv[]);

  static Local<Object> New(Isolate* isolate);

  V8_INLINE static Object* Cast(Value* obj);

 private:
  Object();
  static void CheckCast(Value* obj);
  Local<Value> SlowGetInternalField(int index);
  void* SlowGetAlignedPointerFromInternalField(int index);
};


class V8_EXPORT Array : public Object {
 public:
  uint32_t Length() const;

  Local<Object> CloneElementAt(uint32_t index);

  static Local<Array> New(Isolate* isolate, int length = 0);

  V8_INLINE static Array* Cast(Value* obj);
 private:
  Array();
  static void CheckCast(Value* obj);
};


template<typename T>
class ReturnValue {
 public:
  template <class S> V8_INLINE ReturnValue(const ReturnValue<S>& that)
      : value_(that.value_) {
    TYPE_CHECK(T, S);
  }
  // Handle setters
  template <typename S> V8_INLINE void Set(const Persistent<S>& handle);
  template <typename S> V8_INLINE void Set(const Handle<S> handle);
  // Fast primitive setters
  V8_INLINE void Set(bool value);
  V8_INLINE void Set(double i);
  V8_INLINE void Set(int32_t i);
  V8_INLINE void Set(uint32_t i);
  // Fast JS primitive setters
  V8_INLINE void SetNull();
  V8_INLINE void SetUndefined();
  V8_INLINE void SetEmptyString();
  // Convenience getter for Isolate
  V8_INLINE Isolate* GetIsolate();

 private:
  template<class F> friend class ReturnValue;
  template<class F> friend class FunctionCallbackInfo;
  template<class F> friend class PropertyCallbackInfo;
  template<class F, class G, class H> friend class PersistentValueMap;
  V8_INLINE void SetInternal(internal::Object* value) { *value_ = value; }
  V8_INLINE internal::Object* GetDefaultValue();
  V8_INLINE explicit ReturnValue(internal::Object** slot);
  internal::Object** value_;
};


template<typename T>
class FunctionCallbackInfo {
 public:
  V8_INLINE int Length() const;
  V8_INLINE Local<Value> operator[](int i) const;
  V8_INLINE Local<Function> Callee() const;
  V8_INLINE Local<Object> This() const;
  V8_INLINE Local<Object> Holder() const;
  V8_INLINE bool IsConstructCall() const;
  V8_INLINE Local<Value> Data() const;
  V8_INLINE Isolate* GetIsolate() const;
  V8_INLINE ReturnValue<T> GetReturnValue() const;
  // This shouldn't be public, but the arm compiler needs it.
  static const int kArgsLength = 7;

 protected:
  friend class internal::FunctionCallbackArguments;
  friend class internal::CustomArguments<FunctionCallbackInfo>;
  static const int kHolderIndex = 0;
  static const int kIsolateIndex = 1;
  static const int kReturnValueDefaultValueIndex = 2;
  static const int kReturnValueIndex = 3;
  static const int kDataIndex = 4;
  static const int kCalleeIndex = 5;
  static const int kContextSaveIndex = 6;

  V8_INLINE FunctionCallbackInfo(internal::Object** implicit_args,
                   internal::Object** values,
                   int length,
                   bool is_construct_call);
  internal::Object** implicit_args_;
  internal::Object** values_;
  int length_;
  bool is_construct_call_;
};


template<typename T>
class PropertyCallbackInfo {
 public:
  V8_INLINE Isolate* GetIsolate() const;
  V8_INLINE Local<Value> Data() const;
  V8_INLINE Local<Object> This() const;
  V8_INLINE Local<Object> Holder() const;
  V8_INLINE ReturnValue<T> GetReturnValue() const;
  // This shouldn't be public, but the arm compiler needs it.
  static const int kArgsLength = 6;

 protected:
  friend class MacroAssembler;
  friend class internal::PropertyCallbackArguments;
  friend class internal::CustomArguments<PropertyCallbackInfo>;
  static const int kHolderIndex = 0;
  static const int kIsolateIndex = 1;
  static const int kReturnValueDefaultValueIndex = 2;
  static const int kReturnValueIndex = 3;
  static const int kDataIndex = 4;
  static const int kThisIndex = 5;

  V8_INLINE PropertyCallbackInfo(internal::Object** args) : args_(args) {}
  internal::Object** args_;
};


typedef void (*FunctionCallback)(const FunctionCallbackInfo<Value>& info);


class V8_EXPORT Function : public Object {
 public:
  static Local<Function> New(Isolate* isolate,
                             FunctionCallback callback,
                             Local<Value> data = Local<Value>(),
                             int length = 0);

  Local<Object> NewInstance() const;
  Local<Object> NewInstance(int argc, Handle<Value> argv[]) const;
  Local<Value> Call(Handle<Value> recv, int argc, Handle<Value> argv[]);
  void SetName(Handle<String> name);
  Handle<Value> GetName() const;

  Handle<Value> GetInferredName() const;

  Handle<Value> GetDisplayName() const;

  int GetScriptLineNumber() const;
  int GetScriptColumnNumber() const;

  bool IsBuiltin() const;

  int ScriptId() const;

  Local<Value> GetBoundFunction() const;

  ScriptOrigin GetScriptOrigin() const;
  V8_INLINE static Function* Cast(Value* obj);
  static const int kLineOffsetNotFound;

 private:
  Function();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Promise : public Object {
 public:
  class V8_EXPORT Resolver : public Object {
   public:
    static Local<Resolver> New(Isolate* isolate);

    Local<Promise> GetPromise();

    void Resolve(Handle<Value> value);
    void Reject(Handle<Value> value);

    V8_INLINE static Resolver* Cast(Value* obj);

   private:
    Resolver();
    static void CheckCast(Value* obj);
  };

  Local<Promise> Chain(Handle<Function> handler);
  Local<Promise> Catch(Handle<Function> handler);

  V8_INLINE static Promise* Cast(Value* obj);

 private:
  Promise();
  static void CheckCast(Value* obj);
};


#ifndef V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT
// The number of required internal fields can be defined by embedder.
#define V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT 2
#endif

class V8_EXPORT ArrayBuffer : public Object {
 public:
  class V8_EXPORT Allocator { // NOLINT
   public:
    virtual ~Allocator() {}

    virtual void* Allocate(size_t length) = 0;

    virtual void* AllocateUninitialized(size_t length) = 0;
    virtual void Free(void* data, size_t length) = 0;
  };

  class V8_EXPORT Contents { // NOLINT
   public:
    Contents() : data_(NULL), byte_length_(0) {}

    void* Data() const { return data_; }
    size_t ByteLength() const { return byte_length_; }

   private:
    void* data_;
    size_t byte_length_;

    friend class ArrayBuffer;
  };


  size_t ByteLength() const;

  static Local<ArrayBuffer> New(Isolate* isolate, size_t byte_length);

  static Local<ArrayBuffer> New(Isolate* isolate, void* data,
                                size_t byte_length);

  bool IsExternal() const;

  void Neuter();

  Contents Externalize();

  V8_INLINE static ArrayBuffer* Cast(Value* obj);

  static const int kInternalFieldCount = V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT;

 private:
  ArrayBuffer();
  static void CheckCast(Value* obj);
};


#ifndef V8_ARRAY_BUFFER_VIEW_INTERNAL_FIELD_COUNT
// The number of required internal fields can be defined by embedder.
#define V8_ARRAY_BUFFER_VIEW_INTERNAL_FIELD_COUNT 2
#endif


class V8_EXPORT ArrayBufferView : public Object {
 public:
  Local<ArrayBuffer> Buffer();
  size_t ByteOffset();
  size_t ByteLength();

  V8_INLINE static ArrayBufferView* Cast(Value* obj);

  static const int kInternalFieldCount =
      V8_ARRAY_BUFFER_VIEW_INTERNAL_FIELD_COUNT;

 private:
  ArrayBufferView();
  static void CheckCast(Value* obj);
};


class V8_EXPORT TypedArray : public ArrayBufferView {
 public:
  size_t Length();

  V8_INLINE static TypedArray* Cast(Value* obj);

 private:
  TypedArray();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Uint8Array : public TypedArray {
 public:
  static Local<Uint8Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Uint8Array* Cast(Value* obj);

 private:
  Uint8Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Uint8ClampedArray : public TypedArray {
 public:
  static Local<Uint8ClampedArray> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Uint8ClampedArray* Cast(Value* obj);

 private:
  Uint8ClampedArray();
  static void CheckCast(Value* obj);
};

class V8_EXPORT Int8Array : public TypedArray {
 public:
  static Local<Int8Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Int8Array* Cast(Value* obj);

 private:
  Int8Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Uint16Array : public TypedArray {
 public:
  static Local<Uint16Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Uint16Array* Cast(Value* obj);

 private:
  Uint16Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Int16Array : public TypedArray {
 public:
  static Local<Int16Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Int16Array* Cast(Value* obj);

 private:
  Int16Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Uint32Array : public TypedArray {
 public:
  static Local<Uint32Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Uint32Array* Cast(Value* obj);

 private:
  Uint32Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Int32Array : public TypedArray {
 public:
  static Local<Int32Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Int32Array* Cast(Value* obj);

 private:
  Int32Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Float32Array : public TypedArray {
 public:
  static Local<Float32Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Float32Array* Cast(Value* obj);

 private:
  Float32Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Float64Array : public TypedArray {
 public:
  static Local<Float64Array> New(Handle<ArrayBuffer> array_buffer,
                               size_t byte_offset, size_t length);
  V8_INLINE static Float64Array* Cast(Value* obj);

 private:
  Float64Array();
  static void CheckCast(Value* obj);
};


class V8_EXPORT DataView : public ArrayBufferView {
 public:
  static Local<DataView> New(Handle<ArrayBuffer> array_buffer,
                             size_t byte_offset, size_t length);
  V8_INLINE static DataView* Cast(Value* obj);

 private:
  DataView();
  static void CheckCast(Value* obj);
};


class V8_EXPORT Date : public Object {
 public:
  static Local<Value> New(Isolate* isolate, double time);

  double ValueOf() const;

  V8_INLINE static Date* Cast(v8::Value* obj);

  static void DateTimeConfigurationChangeNotification(Isolate* isolate);

 private:
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT NumberObject : public Object {
 public:
  static Local<Value> New(Isolate* isolate, double value);

  double ValueOf() const;

  V8_INLINE static NumberObject* Cast(v8::Value* obj);

 private:
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT BooleanObject : public Object {
 public:
  static Local<Value> New(bool value);

  bool ValueOf() const;

  V8_INLINE static BooleanObject* Cast(v8::Value* obj);

 private:
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT StringObject : public Object {
 public:
  static Local<Value> New(Handle<String> value);

  Local<String> ValueOf() const;

  V8_INLINE static StringObject* Cast(v8::Value* obj);

 private:
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT SymbolObject : public Object {
 public:
  static Local<Value> New(Isolate* isolate, Handle<Symbol> value);

  Local<Symbol> ValueOf() const;

  V8_INLINE static SymbolObject* Cast(v8::Value* obj);

 private:
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT RegExp : public Object {
 public:
  enum Flags {
    kNone = 0,
    kGlobal = 1,
    kIgnoreCase = 2,
    kMultiline = 4
  };

  static Local<RegExp> New(Handle<String> pattern, Flags flags);

  Local<String> GetSource() const;

  Flags GetFlags() const;

  V8_INLINE static RegExp* Cast(v8::Value* obj);

 private:
  static void CheckCast(v8::Value* obj);
};


class V8_EXPORT External : public Value {
 public:
  static Local<External> New(Isolate* isolate, void* value);
  V8_INLINE static External* Cast(Value* obj);
  void* Value() const;
 private:
  static void CheckCast(v8::Value* obj);
};


// --- Templates ---


class V8_EXPORT Template : public Data {
 public:
  void Set(Handle<String> name, Handle<Data> value,
           PropertyAttribute attributes = None);
  V8_INLINE void Set(Isolate* isolate, const char* name, Handle<Data> value);

  void SetAccessorProperty(
     Local<String> name,
     Local<FunctionTemplate> getter = Local<FunctionTemplate>(),
     Local<FunctionTemplate> setter = Local<FunctionTemplate>(),
     PropertyAttribute attribute = None,
     AccessControl settings = DEFAULT);

  void SetNativeDataProperty(Local<String> name,
                             AccessorGetterCallback getter,
                             AccessorSetterCallback setter = 0,
                             // TODO(dcarney): gcc can't handle Local below
                             Handle<Value> data = Handle<Value>(),
                             PropertyAttribute attribute = None,
                             Local<AccessorSignature> signature =
                                 Local<AccessorSignature>(),
                             AccessControl settings = DEFAULT);

  // This function is not yet stable and should not be used at this time.
  bool SetDeclaredAccessor(Local<String> name,
                           Local<DeclaredAccessorDescriptor> descriptor,
                           PropertyAttribute attribute = None,
                           Local<AccessorSignature> signature =
                               Local<AccessorSignature>(),
                           AccessControl settings = DEFAULT);

 private:
  Template();

  friend class ObjectTemplate;
  friend class FunctionTemplate;
};


typedef void (*NamedPropertyGetterCallback)(
    Local<String> property,
    const PropertyCallbackInfo<Value>& info);


typedef void (*NamedPropertySetterCallback)(
    Local<String> property,
    Local<Value> value,
    const PropertyCallbackInfo<Value>& info);


typedef void (*NamedPropertyQueryCallback)(
    Local<String> property,
    const PropertyCallbackInfo<Integer>& info);


typedef void (*NamedPropertyDeleterCallback)(
    Local<String> property,
    const PropertyCallbackInfo<Boolean>& info);


typedef void (*NamedPropertyEnumeratorCallback)(
    const PropertyCallbackInfo<Array>& info);


typedef void (*IndexedPropertyGetterCallback)(
    uint32_t index,
    const PropertyCallbackInfo<Value>& info);


typedef void (*IndexedPropertySetterCallback)(
    uint32_t index,
    Local<Value> value,
    const PropertyCallbackInfo<Value>& info);


typedef void (*IndexedPropertyQueryCallback)(
    uint32_t index,
    const PropertyCallbackInfo<Integer>& info);


typedef void (*IndexedPropertyDeleterCallback)(
    uint32_t index,
    const PropertyCallbackInfo<Boolean>& info);


typedef void (*IndexedPropertyEnumeratorCallback)(
    const PropertyCallbackInfo<Array>& info);


enum AccessType {
  ACCESS_GET,
  ACCESS_SET,
  ACCESS_HAS,
  ACCESS_DELETE,
  ACCESS_KEYS
};


typedef bool (*NamedSecurityCallback)(Local<Object> host,
                                      Local<Value> key,
                                      AccessType type,
                                      Local<Value> data);


typedef bool (*IndexedSecurityCallback)(Local<Object> host,
                                        uint32_t index,
                                        AccessType type,
                                        Local<Value> data);


class V8_EXPORT FunctionTemplate : public Template {
 public:
  static Local<FunctionTemplate> New(
      Isolate* isolate,
      FunctionCallback callback = 0,
      Handle<Value> data = Handle<Value>(),
      Handle<Signature> signature = Handle<Signature>(),
      int length = 0);

  Local<Function> GetFunction();

  void SetCallHandler(FunctionCallback callback,
                      Handle<Value> data = Handle<Value>());

  void SetLength(int length);

  Local<ObjectTemplate> InstanceTemplate();

  void Inherit(Handle<FunctionTemplate> parent);

  Local<ObjectTemplate> PrototypeTemplate();

  void SetClassName(Handle<String> name);

  void SetHiddenPrototype(bool value);

  void ReadOnlyPrototype();

  void RemovePrototype();

  bool HasInstance(Handle<Value> object);

 private:
  FunctionTemplate();
  friend class Context;
  friend class ObjectTemplate;
};


class V8_EXPORT ObjectTemplate : public Template {
 public:
  static Local<ObjectTemplate> New(Isolate* isolate);
  // Will be deprecated soon.
  static Local<ObjectTemplate> New();

  Local<Object> NewInstance();

  void SetAccessor(Handle<String> name,
                   AccessorGetterCallback getter,
                   AccessorSetterCallback setter = 0,
                   Handle<Value> data = Handle<Value>(),
                   AccessControl settings = DEFAULT,
                   PropertyAttribute attribute = None,
                   Handle<AccessorSignature> signature =
                       Handle<AccessorSignature>());

  void SetNamedPropertyHandler(
      NamedPropertyGetterCallback getter,
      NamedPropertySetterCallback setter = 0,
      NamedPropertyQueryCallback query = 0,
      NamedPropertyDeleterCallback deleter = 0,
      NamedPropertyEnumeratorCallback enumerator = 0,
      Handle<Value> data = Handle<Value>());

  void SetIndexedPropertyHandler(
      IndexedPropertyGetterCallback getter,
      IndexedPropertySetterCallback setter = 0,
      IndexedPropertyQueryCallback query = 0,
      IndexedPropertyDeleterCallback deleter = 0,
      IndexedPropertyEnumeratorCallback enumerator = 0,
      Handle<Value> data = Handle<Value>());

  void SetCallAsFunctionHandler(FunctionCallback callback,
                                Handle<Value> data = Handle<Value>());

  void MarkAsUndetectable();

  void SetAccessCheckCallbacks(NamedSecurityCallback named_handler,
                               IndexedSecurityCallback indexed_handler,
                               Handle<Value> data = Handle<Value>(),
                               bool turned_on_by_default = true);

  int InternalFieldCount();

  void SetInternalFieldCount(int value);

 private:
  ObjectTemplate();
  static Local<ObjectTemplate> New(internal::Isolate* isolate,
                                   Handle<FunctionTemplate> constructor);
  friend class FunctionTemplate;
};


class V8_EXPORT Signature : public Data {
 public:
  static Local<Signature> New(Isolate* isolate,
                              Handle<FunctionTemplate> receiver =
                                  Handle<FunctionTemplate>(),
                              int argc = 0,
                              Handle<FunctionTemplate> argv[] = 0);

 private:
  Signature();
};


class V8_EXPORT AccessorSignature : public Data {
 public:
  static Local<AccessorSignature> New(Isolate* isolate,
                                      Handle<FunctionTemplate> receiver =
                                          Handle<FunctionTemplate>());

 private:
  AccessorSignature();
};


class V8_EXPORT DeclaredAccessorDescriptor : public Data {
 private:
  DeclaredAccessorDescriptor();
};


class V8_EXPORT ObjectOperationDescriptor : public Data {
 public:
  // This function is not yet stable and should not be used at this time.
  static Local<RawOperationDescriptor> NewInternalFieldDereference(
      Isolate* isolate,
      int internal_field);
 private:
  ObjectOperationDescriptor();
};


enum DeclaredAccessorDescriptorDataType {
    kDescriptorBoolType,
    kDescriptorInt8Type, kDescriptorUint8Type,
    kDescriptorInt16Type, kDescriptorUint16Type,
    kDescriptorInt32Type, kDescriptorUint32Type,
    kDescriptorFloatType, kDescriptorDoubleType
};


class V8_EXPORT RawOperationDescriptor : public Data {
 public:
  Local<DeclaredAccessorDescriptor> NewHandleDereference(Isolate* isolate);
  Local<RawOperationDescriptor> NewRawDereference(Isolate* isolate);
  Local<RawOperationDescriptor> NewRawShift(Isolate* isolate,
                                            int16_t byte_offset);
  Local<DeclaredAccessorDescriptor> NewPointerCompare(Isolate* isolate,
                                                      void* compare_value);
  Local<DeclaredAccessorDescriptor> NewPrimitiveValue(
      Isolate* isolate,
      DeclaredAccessorDescriptorDataType data_type,
      uint8_t bool_offset = 0);
  Local<DeclaredAccessorDescriptor> NewBitmaskCompare8(Isolate* isolate,
                                                       uint8_t bitmask,
                                                       uint8_t compare_value);
  Local<DeclaredAccessorDescriptor> NewBitmaskCompare16(
      Isolate* isolate,
      uint16_t bitmask,
      uint16_t compare_value);
  Local<DeclaredAccessorDescriptor> NewBitmaskCompare32(
      Isolate* isolate,
      uint32_t bitmask,
      uint32_t compare_value);

 private:
  RawOperationDescriptor();
};


class V8_EXPORT TypeSwitch : public Data {
 public:
  static Local<TypeSwitch> New(Handle<FunctionTemplate> type);
  static Local<TypeSwitch> New(int argc, Handle<FunctionTemplate> types[]);
  int match(Handle<Value> value);
 private:
  TypeSwitch();
};


// --- Extensions ---

class V8_EXPORT ExternalAsciiStringResourceImpl
    : public String::ExternalAsciiStringResource {
 public:
  ExternalAsciiStringResourceImpl() : data_(0), length_(0) {}
  ExternalAsciiStringResourceImpl(const char* data, size_t length)
      : data_(data), length_(length) {}
  const char* data() const { return data_; }
  size_t length() const { return length_; }

 private:
  const char* data_;
  size_t length_;
};

class V8_EXPORT Extension {  // NOLINT
 public:
  // Note that the strings passed into this constructor must live as long
  // as the Extension itself.
  Extension(const char* name,
            const char* source = 0,
            int dep_count = 0,
            const char** deps = 0,
            int source_length = -1);
  virtual ~Extension() { }
  virtual v8::Handle<v8::FunctionTemplate> GetNativeFunctionTemplate(
      v8::Isolate* isolate, v8::Handle<v8::String> name) {
    return v8::Handle<v8::FunctionTemplate>();
  }

  const char* name() const { return name_; }
  size_t source_length() const { return source_length_; }
  const String::ExternalAsciiStringResource* source() const {
    return &source_; }
  int dependency_count() { return dep_count_; }
  const char** dependencies() { return deps_; }
  void set_auto_enable(bool value) { auto_enable_ = value; }
  bool auto_enable() { return auto_enable_; }

 private:
  const char* name_;
  size_t source_length_;  // expected to initialize before source_
  ExternalAsciiStringResourceImpl source_;
  int dep_count_;
  const char** deps_;
  bool auto_enable_;

  // Disallow copying and assigning.
  Extension(const Extension&);
  void operator=(const Extension&);
};


void V8_EXPORT RegisterExtension(Extension* extension);


// --- Statics ---

V8_INLINE Handle<Primitive> Undefined(Isolate* isolate);
V8_INLINE Handle<Primitive> Null(Isolate* isolate);
V8_INLINE Handle<Boolean> True(Isolate* isolate);
V8_INLINE Handle<Boolean> False(Isolate* isolate);


class V8_EXPORT ResourceConstraints {
 public:
  ResourceConstraints();

  void ConfigureDefaults(uint64_t physical_memory,
                         uint32_t number_of_processors);

  int max_young_space_size() const { return max_young_space_size_; }
  void set_max_young_space_size(int value) { max_young_space_size_ = value; }
  int max_old_space_size() const { return max_old_space_size_; }
  void set_max_old_space_size(int value) { max_old_space_size_ = value; }
  int max_executable_size() const { return max_executable_size_; }
  void set_max_executable_size(int value) { max_executable_size_ = value; }
  uint32_t* stack_limit() const { return stack_limit_; }
  // Sets an address beyond which the VM's stack may not grow.
  void set_stack_limit(uint32_t* value) { stack_limit_ = value; }
  int max_available_threads() const { return max_available_threads_; }
  // Set the number of threads available to V8, assuming at least 1.
  void set_max_available_threads(int value) {
    max_available_threads_ = value;
  }

 private:
  int max_young_space_size_;
  int max_old_space_size_;
  int max_executable_size_;
  uint32_t* stack_limit_;
  int max_available_threads_;
};


bool V8_EXPORT SetResourceConstraints(Isolate* isolate,
                                      ResourceConstraints* constraints);


// --- Exceptions ---


typedef void (*FatalErrorCallback)(const char* location, const char* message);


typedef void (*MessageCallback)(Handle<Message> message, Handle<Value> error);

// --- Tracing ---

typedef void (*LogEventCallback)(const char* name, int event);

class V8_EXPORT Exception {
 public:
  static Local<Value> RangeError(Handle<String> message);
  static Local<Value> ReferenceError(Handle<String> message);
  static Local<Value> SyntaxError(Handle<String> message);
  static Local<Value> TypeError(Handle<String> message);
  static Local<Value> Error(Handle<String> message);
};


// --- Counters Callbacks ---

typedef int* (*CounterLookupCallback)(const char* name);

typedef void* (*CreateHistogramCallback)(const char* name,
                                         int min,
                                         int max,
                                         size_t buckets);

typedef void (*AddHistogramSampleCallback)(void* histogram, int sample);

// --- Memory Allocation Callback ---
  enum ObjectSpace {
    kObjectSpaceNewSpace = 1 << 0,
    kObjectSpaceOldPointerSpace = 1 << 1,
    kObjectSpaceOldDataSpace = 1 << 2,
    kObjectSpaceCodeSpace = 1 << 3,
    kObjectSpaceMapSpace = 1 << 4,
    kObjectSpaceLoSpace = 1 << 5,

    kObjectSpaceAll = kObjectSpaceNewSpace | kObjectSpaceOldPointerSpace |
      kObjectSpaceOldDataSpace | kObjectSpaceCodeSpace | kObjectSpaceMapSpace |
      kObjectSpaceLoSpace
  };

  enum AllocationAction {
    kAllocationActionAllocate = 1 << 0,
    kAllocationActionFree = 1 << 1,
    kAllocationActionAll = kAllocationActionAllocate | kAllocationActionFree
  };

typedef void (*MemoryAllocationCallback)(ObjectSpace space,
                                         AllocationAction action,
                                         int size);

// --- Leave Script Callback ---
typedef void (*CallCompletedCallback)();

// --- Failed Access Check Callback ---
typedef void (*FailedAccessCheckCallback)(Local<Object> target,
                                          AccessType type,
                                          Local<Value> data);

// --- AllowCodeGenerationFromStrings callbacks ---

typedef bool (*AllowCodeGenerationFromStringsCallback)(Local<Context> context);

// --- Garbage Collection Callbacks ---

enum GCType {
  kGCTypeScavenge = 1 << 0,
  kGCTypeMarkSweepCompact = 1 << 1,
  kGCTypeAll = kGCTypeScavenge | kGCTypeMarkSweepCompact
};

enum GCCallbackFlags {
  kNoGCCallbackFlags = 0,
  kGCCallbackFlagCompacted = 1 << 0,
  kGCCallbackFlagConstructRetainedObjectInfos = 1 << 1,
  kGCCallbackFlagForced = 1 << 2
};

typedef void (*GCPrologueCallback)(GCType type, GCCallbackFlags flags);
typedef void (*GCEpilogueCallback)(GCType type, GCCallbackFlags flags);

typedef void (*InterruptCallback)(Isolate* isolate, void* data);


class V8_EXPORT HeapStatistics {
 public:
  HeapStatistics();
  size_t total_heap_size() { return total_heap_size_; }
  size_t total_heap_size_executable() { return total_heap_size_executable_; }
  size_t total_physical_size() { return total_physical_size_; }
  size_t used_heap_size() { return used_heap_size_; }
  size_t heap_size_limit() { return heap_size_limit_; }

 private:
  size_t total_heap_size_;
  size_t total_heap_size_executable_;
  size_t total_physical_size_;
  size_t used_heap_size_;
  size_t heap_size_limit_;

  friend class V8;
  friend class Isolate;
};


class RetainedObjectInfo;

class V8_EXPORT Isolate {
 public:
  class V8_EXPORT Scope {
   public:
    explicit Scope(Isolate* isolate) : isolate_(isolate) {
      isolate->Enter();
    }

    ~Scope() { isolate_->Exit(); }

   private:
    Isolate* const isolate_;

    // Prevent copying of Scope objects.
    Scope(const Scope&);
    Scope& operator=(const Scope&);
  };


  class DisallowJavascriptExecutionScope {
   public:
    enum OnFailure { CRASH_ON_FAILURE, THROW_ON_FAILURE };

    DisallowJavascriptExecutionScope(Isolate* isolate, OnFailure on_failure);
    ~DisallowJavascriptExecutionScope();

   private:
    bool on_failure_;
    void* internal_;

    // Prevent copying of Scope objects.
    DisallowJavascriptExecutionScope(const DisallowJavascriptExecutionScope&);
    DisallowJavascriptExecutionScope& operator=(
        const DisallowJavascriptExecutionScope&);
  };


  class AllowJavascriptExecutionScope {
   public:
    explicit AllowJavascriptExecutionScope(Isolate* isolate);
    ~AllowJavascriptExecutionScope();

   private:
    void* internal_throws_;
    void* internal_assert_;

    // Prevent copying of Scope objects.
    AllowJavascriptExecutionScope(const AllowJavascriptExecutionScope&);
    AllowJavascriptExecutionScope& operator=(
        const AllowJavascriptExecutionScope&);
  };

  enum GarbageCollectionType {
    kFullGarbageCollection,
    kMinorGarbageCollection
  };

  static Isolate* New();

  static Isolate* GetCurrent();

  void Enter();

  void Exit();

  void Dispose();

  V8_INLINE void SetData(uint32_t slot, void* data);

  V8_INLINE void* GetData(uint32_t slot);

  V8_INLINE static uint32_t GetNumberOfDataSlots();

  void GetHeapStatistics(HeapStatistics* heap_statistics);

  int64_t AdjustAmountOfExternalAllocatedMemory(int64_t change_in_bytes);

  HeapProfiler* GetHeapProfiler();

  CpuProfiler* GetCpuProfiler();

  bool InContext();

  Local<Context> GetCurrentContext();

  Local<Context> GetCallingContext();

  Local<Context> GetEnteredContext();

  Local<Value> ThrowException(Local<Value> exception);

  template<typename T> void SetObjectGroupId(const Persistent<T>& object,
                                             UniqueId id);

  template<typename T> void SetReferenceFromGroup(UniqueId id,
                                                  const Persistent<T>& child);

  template<typename T, typename S>
  void SetReference(const Persistent<T>& parent, const Persistent<S>& child);

  typedef void (*GCPrologueCallback)(Isolate* isolate,
                                     GCType type,
                                     GCCallbackFlags flags);
  typedef void (*GCEpilogueCallback)(Isolate* isolate,
                                     GCType type,
                                     GCCallbackFlags flags);

  void AddGCPrologueCallback(
      GCPrologueCallback callback, GCType gc_type_filter = kGCTypeAll);

  void RemoveGCPrologueCallback(GCPrologueCallback callback);

  void AddGCEpilogueCallback(
      GCEpilogueCallback callback, GCType gc_type_filter = kGCTypeAll);

  void RemoveGCEpilogueCallback(GCEpilogueCallback callback);

  void RequestInterrupt(InterruptCallback callback, void* data);

  void ClearInterrupt();

  void RequestGarbageCollectionForTesting(GarbageCollectionType type);

  void SetEventLogger(LogEventCallback that);

 private:
  template<class K, class V, class Traits> friend class PersistentValueMap;

  Isolate();
  Isolate(const Isolate&);
  ~Isolate();
  Isolate& operator=(const Isolate&);
  void* operator new(size_t size);
  void operator delete(void*, size_t);

  void SetObjectGroupId(internal::Object** object, UniqueId id);
  void SetReferenceFromGroup(UniqueId id, internal::Object** object);
  void SetReference(internal::Object** parent, internal::Object** child);
};

class V8_EXPORT StartupData {
 public:
  enum CompressionAlgorithm {
    kUncompressed,
    kBZip2
  };

  const char* data;
  int compressed_size;
  int raw_size;
};


class V8_EXPORT StartupDataDecompressor {  // NOLINT
 public:
  StartupDataDecompressor();
  virtual ~StartupDataDecompressor();
  int Decompress();

 protected:
  virtual int DecompressData(char* raw_data,
                             int* raw_data_size,
                             const char* compressed_data,
                             int compressed_data_size) = 0;

 private:
  char** raw_data;
};


typedef bool (*EntropySource)(unsigned char* buffer, size_t length);


typedef uintptr_t (*ReturnAddressLocationResolver)(
    uintptr_t return_addr_location);


typedef void (*FunctionEntryHook)(uintptr_t function,
                                  uintptr_t return_addr_location);


struct JitCodeEvent {
  enum EventType {
    CODE_ADDED,
    CODE_MOVED,
    CODE_REMOVED,
    CODE_ADD_LINE_POS_INFO,
    CODE_START_LINE_INFO_RECORDING,
    CODE_END_LINE_INFO_RECORDING
  };
  // Definition of the code position type. The "POSITION" type means the place
  // in the source code which are of interest when making stack traces to
  // pin-point the source location of a stack frame as close as possible.
  // The "STATEMENT_POSITION" means the place at the beginning of each
  // statement, and is used to indicate possible break locations.
  enum PositionType {
    POSITION,
    STATEMENT_POSITION
  };

  // Type of event.
  EventType type;
  // Start of the instructions.
  void* code_start;
  // Size of the instructions.
  size_t code_len;
  // Script info for CODE_ADDED event.
  Handle<Script> script;
  // User-defined data for *_LINE_INFO_* event. It's used to hold the source
  // code line information which is returned from the
  // CODE_START_LINE_INFO_RECORDING event. And it's passed to subsequent
  // CODE_ADD_LINE_POS_INFO and CODE_END_LINE_INFO_RECORDING events.
  void* user_data;

  struct name_t {
    // Name of the object associated with the code, note that the string is not
    // zero-terminated.
    const char* str;
    // Number of chars in str.
    size_t len;
  };

  struct line_info_t {
    // PC offset
    size_t offset;
    // Code postion
    size_t pos;
    // The position type.
    PositionType position_type;
  };

  union {
    // Only valid for CODE_ADDED.
    struct name_t name;

    // Only valid for CODE_ADD_LINE_POS_INFO
    struct line_info_t line_info;

    // New location of instructions. Only valid for CODE_MOVED.
    void* new_code_start;
  };
};

enum JitCodeEventOptions {
  kJitCodeEventDefault = 0,
  // Generate callbacks for already existent code.
  kJitCodeEventEnumExisting = 1
};


typedef void (*JitCodeEventHandler)(const JitCodeEvent* event);


class V8_EXPORT ExternalResourceVisitor {  // NOLINT
 public:
  virtual ~ExternalResourceVisitor() {}
  virtual void VisitExternalString(Handle<String> string) {}
};


class V8_EXPORT PersistentHandleVisitor {  // NOLINT
 public:
  virtual ~PersistentHandleVisitor() {}
  virtual void VisitPersistentHandle(Persistent<Value>* value,
                                     uint16_t class_id) {}
};


class V8_EXPORT V8 {
 public:
  static void SetFatalErrorHandler(FatalErrorCallback that);

  static void SetAllowCodeGenerationFromStringsCallback(
      AllowCodeGenerationFromStringsCallback that);

  static void SetArrayBufferAllocator(ArrayBuffer::Allocator* allocator);

  static bool IsDead();

  static StartupData::CompressionAlgorithm GetCompressedStartupDataAlgorithm();
  static int GetCompressedStartupDataCount();
  static void GetCompressedStartupData(StartupData* compressed_data);
  static void SetDecompressedStartupData(StartupData* decompressed_data);

  static bool AddMessageListener(MessageCallback that,
                                 Handle<Value> data = Handle<Value>());

  static void RemoveMessageListeners(MessageCallback that);

  static void SetCaptureStackTraceForUncaughtExceptions(
      bool capture,
      int frame_limit = 10,
      StackTrace::StackTraceOptions options = StackTrace::kOverview);

  static void SetFlagsFromString(const char* str, int length);

  static void SetFlagsFromCommandLine(int* argc,
                                      char** argv,
                                      bool remove_flags);

  static const char* GetVersion();

  static void SetCounterFunction(CounterLookupCallback);

  static void SetCreateHistogramFunction(CreateHistogramCallback);
  static void SetAddHistogramSampleFunction(AddHistogramSampleCallback);

  static void SetFailedAccessCheckCallbackFunction(FailedAccessCheckCallback);

  static void AddGCPrologueCallback(
      GCPrologueCallback callback, GCType gc_type_filter = kGCTypeAll);

  static void RemoveGCPrologueCallback(GCPrologueCallback callback);

  static void AddGCEpilogueCallback(
      GCEpilogueCallback callback, GCType gc_type_filter = kGCTypeAll);

  static void RemoveGCEpilogueCallback(GCEpilogueCallback callback);

  static void AddMemoryAllocationCallback(MemoryAllocationCallback callback,
                                          ObjectSpace space,
                                          AllocationAction action);

  static void RemoveMemoryAllocationCallback(MemoryAllocationCallback callback);

  static void AddCallCompletedCallback(CallCompletedCallback callback);

  static void RemoveCallCompletedCallback(CallCompletedCallback callback);

  static void RunMicrotasks(Isolate* isolate);

  static void EnqueueMicrotask(Isolate* isolate, Handle<Function> microtask);

  static void SetAutorunMicrotasks(Isolate *source, bool autorun);

  static bool Initialize();

  static void SetEntropySource(EntropySource source);

  static void SetReturnAddressLocationResolver(
      ReturnAddressLocationResolver return_address_resolver);

  static bool SetFunctionEntryHook(Isolate* isolate,
                                   FunctionEntryHook entry_hook);

  static void SetJitCodeEventHandler(JitCodeEventOptions options,
                                     JitCodeEventHandler event_handler);

  static void TerminateExecution(Isolate* isolate = NULL);

  static bool IsExecutionTerminating(Isolate* isolate = NULL);

  static void CancelTerminateExecution(Isolate* isolate);

  static bool Dispose();

  static void VisitExternalResources(ExternalResourceVisitor* visitor);

  static void VisitHandlesWithClassIds(PersistentHandleVisitor* visitor);

  static void VisitHandlesForPartialDependence(
      Isolate* isolate, PersistentHandleVisitor* visitor);

  static bool IdleNotification(int hint = 1000);

  static void LowMemoryNotification();

  static int ContextDisposedNotification();

  static bool InitializeICU(const char* icu_data_file = NULL);

  static void InitializePlatform(Platform* platform);

  static void ShutdownPlatform();

 private:
  V8();

  static internal::Object** GlobalizeReference(internal::Isolate* isolate,
                                               internal::Object** handle);
  static internal::Object** CopyPersistent(internal::Object** handle);
  static void DisposeGlobal(internal::Object** global_handle);
  typedef WeakCallbackData<Value, void>::Callback WeakCallback;
  static void MakeWeak(internal::Object** global_handle,
                       void* data,
                       WeakCallback weak_callback);
  static void* ClearWeak(internal::Object** global_handle);
  static void Eternalize(Isolate* isolate,
                         Value* handle,
                         int* index);
  static Local<Value> GetEternal(Isolate* isolate, int index);

  template <class T> friend class Handle;
  template <class T> friend class Local;
  template <class T> friend class Eternal;
  template <class T> friend class PersistentBase;
  template <class T, class M> friend class Persistent;
  friend class Context;
};


class V8_EXPORT TryCatch {
 public:
  TryCatch();

  ~TryCatch();

  bool HasCaught() const;

  bool CanContinue() const;

  bool HasTerminated() const;

  Handle<Value> ReThrow();

  Local<Value> Exception() const;

  Local<Value> StackTrace() const;

  Local<v8::Message> Message() const;

  void Reset();

  void SetVerbose(bool value);

  void SetCaptureMessage(bool value);

 private:
  // Make it hard to create heap-allocated TryCatch blocks.
  TryCatch(const TryCatch&);
  void operator=(const TryCatch&);
  void* operator new(size_t size);
  void operator delete(void*, size_t);

  v8::internal::Isolate* isolate_;
  void* next_;
  void* exception_;
  void* message_obj_;
  void* message_script_;
  int message_start_pos_;
  int message_end_pos_;
  bool is_verbose_ : 1;
  bool can_continue_ : 1;
  bool capture_message_ : 1;
  bool rethrow_ : 1;
  bool has_terminated_ : 1;

  friend class v8::internal::Isolate;
};


// --- Context ---


class V8_EXPORT ExtensionConfiguration {
 public:
  ExtensionConfiguration() : name_count_(0), names_(NULL) { }
  ExtensionConfiguration(int name_count, const char* names[])
      : name_count_(name_count), names_(names) { }

  const char** begin() const { return &names_[0]; }
  const char** end()  const { return &names_[name_count_]; }

 private:
  const int name_count_;
  const char** names_;
};


class V8_EXPORT Context {
 public:
  Local<Object> Global();

  void DetachGlobal();

  static Local<Context> New(
      Isolate* isolate,
      ExtensionConfiguration* extensions = NULL,
      Handle<ObjectTemplate> global_template = Handle<ObjectTemplate>(),
      Handle<Value> global_object = Handle<Value>());

  void SetSecurityToken(Handle<Value> token);

  void UseDefaultSecurityToken();

  Handle<Value> GetSecurityToken();

  void Enter();

  void Exit();

  bool HasOutOfMemoryException() { return false; }

  v8::Isolate* GetIsolate();

  V8_INLINE Local<Value> GetEmbedderData(int index);

  void SetEmbedderData(int index, Handle<Value> value);

  V8_INLINE void* GetAlignedPointerFromEmbedderData(int index);

  void SetAlignedPointerInEmbedderData(int index, void* value);

  void AllowCodeGenerationFromStrings(bool allow);

  bool IsCodeGenerationFromStringsAllowed();

  void SetErrorMessageForCodeGenerationFromStrings(Handle<String> message);

  class Scope {
   public:
    explicit V8_INLINE Scope(Handle<Context> context) : context_(context) {
      context_->Enter();
    }
    V8_INLINE ~Scope() { context_->Exit(); }

   private:
    Handle<Context> context_;
  };

 private:
  friend class Value;
  friend class Script;
  friend class Object;
  friend class Function;

  Local<Value> SlowGetEmbedderData(int index);
  void* SlowGetAlignedPointerFromEmbedderData(int index);
};


class V8_EXPORT Unlocker {
 public:
  V8_INLINE explicit Unlocker(Isolate* isolate) { Initialize(isolate); }

  ~Unlocker();
 private:
  void Initialize(Isolate* isolate);

  internal::Isolate* isolate_;
};


class V8_EXPORT Locker {
 public:
  V8_INLINE explicit Locker(Isolate* isolate) { Initialize(isolate); }

  ~Locker();

  static bool IsLocked(Isolate* isolate);

  static bool IsActive();

 private:
  void Initialize(Isolate* isolate);

  bool has_lock_;
  bool top_level_;
  internal::Isolate* isolate_;

  static bool active_;

  // Disallow copying and assigning.
  Locker(const Locker&);
  void operator=(const Locker&);
};


// --- Implementation ---


namespace internal {

const int kApiPointerSize = sizeof(void*);  // NOLINT
const int kApiIntSize = sizeof(int);  // NOLINT

// Tag information for HeapObject.
const int kHeapObjectTag = 1;
const int kHeapObjectTagSize = 2;
const intptr_t kHeapObjectTagMask = (1 << kHeapObjectTagSize) - 1;

// Tag information for Smi.
const int kSmiTag = 0;
const int kSmiTagSize = 1;
const intptr_t kSmiTagMask = (1 << kSmiTagSize) - 1;

template <size_t ptr_size> struct SmiTagging;

template<int kSmiShiftSize>
V8_INLINE internal::Object* IntToSmi(int value) {
  int smi_shift_bits = kSmiTagSize + kSmiShiftSize;
  intptr_t tagged_value =
      (static_cast<intptr_t>(value) << smi_shift_bits) | kSmiTag;
  return reinterpret_cast<internal::Object*>(tagged_value);
}

// Smi constants for 32-bit systems.
template <> struct SmiTagging<4> {
  static const int kSmiShiftSize = 0;
  static const int kSmiValueSize = 31;
  V8_INLINE static int SmiToInt(internal::Object* value) {
    int shift_bits = kSmiTagSize + kSmiShiftSize;
    // Throw away top 32 bits and shift down (requires >> to be sign extending).
    return static_cast<int>(reinterpret_cast<intptr_t>(value)) >> shift_bits;
  }
  V8_INLINE static internal::Object* IntToSmi(int value) {
    return internal::IntToSmi<kSmiShiftSize>(value);
  }
  V8_INLINE static bool IsValidSmi(intptr_t value) {
    // To be representable as an tagged small integer, the two
    // most-significant bits of 'value' must be either 00 or 11 due to
    // sign-extension. To check this we add 01 to the two
    // most-significant bits, and check if the most-significant bit is 0
    //
    // CAUTION: The original code below:
    // bool result = ((value + 0x40000000) & 0x80000000) == 0;
    // may lead to incorrect results according to the C language spec, and
    // in fact doesn't work correctly with gcc4.1.1 in some cases: The
    // compiler may produce undefined results in case of signed integer
    // overflow. The computation must be done w/ unsigned ints.
    return static_cast<uintptr_t>(value + 0x40000000U) < 0x80000000U;
  }
};

// Smi constants for 64-bit systems.
template <> struct SmiTagging<8> {
  static const int kSmiShiftSize = 31;
  static const int kSmiValueSize = 32;
  V8_INLINE static int SmiToInt(internal::Object* value) {
    int shift_bits = kSmiTagSize + kSmiShiftSize;
    // Shift down and throw away top 32 bits.
    return static_cast<int>(reinterpret_cast<intptr_t>(value) >> shift_bits);
  }
  V8_INLINE static internal::Object* IntToSmi(int value) {
    return internal::IntToSmi<kSmiShiftSize>(value);
  }
  V8_INLINE static bool IsValidSmi(intptr_t value) {
    // To be representable as a long smi, the value must be a 32-bit integer.
    return (value == static_cast<int32_t>(value));
  }
};

typedef SmiTagging<kApiPointerSize> PlatformSmiTagging;
const int kSmiShiftSize = PlatformSmiTagging::kSmiShiftSize;
const int kSmiValueSize = PlatformSmiTagging::kSmiValueSize;
V8_INLINE static bool SmiValuesAre31Bits() { return kSmiValueSize == 31; }
V8_INLINE static bool SmiValuesAre32Bits() { return kSmiValueSize == 32; }

class Internals {
 public:
  // These values match non-compiler-dependent values defined within
  // the implementation of v8.
  static const int kHeapObjectMapOffset = 0;
  static const int kMapInstanceTypeOffset = 1 * kApiPointerSize + kApiIntSize;
  static const int kStringResourceOffset = 3 * kApiPointerSize;

  static const int kOddballKindOffset = 3 * kApiPointerSize;
  static const int kForeignAddressOffset = kApiPointerSize;
  static const int kJSObjectHeaderSize = 3 * kApiPointerSize;
  static const int kFixedArrayHeaderSize = 2 * kApiPointerSize;
  static const int kContextHeaderSize = 2 * kApiPointerSize;
  static const int kContextEmbedderDataIndex = 65;
  static const int kFullStringRepresentationMask = 0x07;
  static const int kStringEncodingMask = 0x4;
  static const int kExternalTwoByteRepresentationTag = 0x02;
  static const int kExternalAsciiRepresentationTag = 0x06;

  static const int kIsolateEmbedderDataOffset = 0 * kApiPointerSize;
  static const int kIsolateRootsOffset = 5 * kApiPointerSize;
  static const int kUndefinedValueRootIndex = 5;
  static const int kNullValueRootIndex = 7;
  static const int kTrueValueRootIndex = 8;
  static const int kFalseValueRootIndex = 9;
  static const int kEmptyStringRootIndex = 154;

  static const int kNodeClassIdOffset = 1 * kApiPointerSize;
  static const int kNodeFlagsOffset = 1 * kApiPointerSize + 3;
  static const int kNodeStateMask = 0xf;
  static const int kNodeStateIsWeakValue = 2;
  static const int kNodeStateIsPendingValue = 3;
  static const int kNodeStateIsNearDeathValue = 4;
  static const int kNodeIsIndependentShift = 4;
  static const int kNodeIsPartiallyDependentShift = 5;

  static const int kJSObjectType = 0xbb;
  static const int kFirstNonstringType = 0x80;
  static const int kOddballType = 0x83;
  static const int kForeignType = 0x87;

  static const int kUndefinedOddballKind = 5;
  static const int kNullOddballKind = 3;

  static const uint32_t kNumIsolateDataSlots = 4;

  V8_EXPORT static void CheckInitializedImpl(v8::Isolate* isolate);
  V8_INLINE static void CheckInitialized(v8::Isolate* isolate) {
#ifdef V8_ENABLE_CHECKS
    CheckInitializedImpl(isolate);
#endif
  }

  V8_INLINE static bool HasHeapObjectTag(internal::Object* value) {
    return ((reinterpret_cast<intptr_t>(value) & kHeapObjectTagMask) ==
            kHeapObjectTag);
  }

  V8_INLINE static int SmiValue(internal::Object* value) {
    return PlatformSmiTagging::SmiToInt(value);
  }

  V8_INLINE static internal::Object* IntToSmi(int value) {
    return PlatformSmiTagging::IntToSmi(value);
  }

  V8_INLINE static bool IsValidSmi(intptr_t value) {
    return PlatformSmiTagging::IsValidSmi(value);
  }

  V8_INLINE static int GetInstanceType(internal::Object* obj) {
    typedef internal::Object O;
    O* map = ReadField<O*>(obj, kHeapObjectMapOffset);
    return ReadField<uint8_t>(map, kMapInstanceTypeOffset);
  }

  V8_INLINE static int GetOddballKind(internal::Object* obj) {
    typedef internal::Object O;
    return SmiValue(ReadField<O*>(obj, kOddballKindOffset));
  }

  V8_INLINE static bool IsExternalTwoByteString(int instance_type) {
    int representation = (instance_type & kFullStringRepresentationMask);
    return representation == kExternalTwoByteRepresentationTag;
  }

  V8_INLINE static uint8_t GetNodeFlag(internal::Object** obj, int shift) {
      uint8_t* addr = reinterpret_cast<uint8_t*>(obj) + kNodeFlagsOffset;
      return *addr & static_cast<uint8_t>(1U << shift);
  }

  V8_INLINE static void UpdateNodeFlag(internal::Object** obj,
                                       bool value, int shift) {
      uint8_t* addr = reinterpret_cast<uint8_t*>(obj) + kNodeFlagsOffset;
      uint8_t mask = static_cast<uint8_t>(1 << shift);
      *addr = static_cast<uint8_t>((*addr & ~mask) | (value << shift));
  }

  V8_INLINE static uint8_t GetNodeState(internal::Object** obj) {
    uint8_t* addr = reinterpret_cast<uint8_t*>(obj) + kNodeFlagsOffset;
    return *addr & kNodeStateMask;
  }

  V8_INLINE static void UpdateNodeState(internal::Object** obj,
                                        uint8_t value) {
    uint8_t* addr = reinterpret_cast<uint8_t*>(obj) + kNodeFlagsOffset;
    *addr = static_cast<uint8_t>((*addr & ~kNodeStateMask) | value);
  }

  V8_INLINE static void SetEmbedderData(v8::Isolate *isolate,
                                        uint32_t slot,
                                        void *data) {
    uint8_t *addr = reinterpret_cast<uint8_t *>(isolate) +
                    kIsolateEmbedderDataOffset + slot * kApiPointerSize;
    *reinterpret_cast<void**>(addr) = data;
  }

  V8_INLINE static void* GetEmbedderData(v8::Isolate* isolate, uint32_t slot) {
    uint8_t* addr = reinterpret_cast<uint8_t*>(isolate) +
        kIsolateEmbedderDataOffset + slot * kApiPointerSize;
    return *reinterpret_cast<void**>(addr);
  }

  V8_INLINE static internal::Object** GetRoot(v8::Isolate* isolate,
                                              int index) {
    uint8_t* addr = reinterpret_cast<uint8_t*>(isolate) + kIsolateRootsOffset;
    return reinterpret_cast<internal::Object**>(addr + index * kApiPointerSize);
  }

  template <typename T> V8_INLINE static T ReadField(Object* ptr, int offset) {
    uint8_t* addr = reinterpret_cast<uint8_t*>(ptr) + offset - kHeapObjectTag;
    return *reinterpret_cast<T*>(addr);
  }

  template <typename T>
  V8_INLINE static T ReadEmbedderData(Context* context, int index) {
    typedef internal::Object O;
    typedef internal::Internals I;
    O* ctx = *reinterpret_cast<O**>(context);
    int embedder_data_offset = I::kContextHeaderSize +
        (internal::kApiPointerSize * I::kContextEmbedderDataIndex);
    O* embedder_data = I::ReadField<O*>(ctx, embedder_data_offset);
    int value_offset =
        I::kFixedArrayHeaderSize + (internal::kApiPointerSize * index);
    return I::ReadField<T>(embedder_data, value_offset);
  }

  V8_INLINE static bool CanCastToHeapObject(void* o) { return false; }
  V8_INLINE static bool CanCastToHeapObject(Context* o) { return true; }
  V8_INLINE static bool CanCastToHeapObject(String* o) { return true; }
  V8_INLINE static bool CanCastToHeapObject(Object* o) { return true; }
  V8_INLINE static bool CanCastToHeapObject(Message* o) { return true; }
  V8_INLINE static bool CanCastToHeapObject(StackTrace* o) { return true; }
  V8_INLINE static bool CanCastToHeapObject(StackFrame* o) { return true; }
};

}  // namespace internal


template <class T>
Local<T>::Local() : Handle<T>() { }


template <class T>
Local<T> Local<T>::New(Isolate* isolate, Handle<T> that) {
  return New(isolate, that.val_);
}

template <class T>
Local<T> Local<T>::New(Isolate* isolate, const PersistentBase<T>& that) {
  return New(isolate, that.val_);
}

template <class T>
Handle<T> Handle<T>::New(Isolate* isolate, T* that) {
  if (that == NULL) return Handle<T>();
  T* that_ptr = that;
  internal::Object** p = reinterpret_cast<internal::Object**>(that_ptr);
  return Handle<T>(reinterpret_cast<T*>(HandleScope::CreateHandle(
      reinterpret_cast<internal::Isolate*>(isolate), *p)));
}


template <class T>
Local<T> Local<T>::New(Isolate* isolate, T* that) {
  if (that == NULL) return Local<T>();
  T* that_ptr = that;
  internal::Object** p = reinterpret_cast<internal::Object**>(that_ptr);
  return Local<T>(reinterpret_cast<T*>(HandleScope::CreateHandle(
      reinterpret_cast<internal::Isolate*>(isolate), *p)));
}


template<class T>
template<class S>
void Eternal<T>::Set(Isolate* isolate, Local<S> handle) {
  TYPE_CHECK(T, S);
  V8::Eternalize(isolate, reinterpret_cast<Value*>(*handle), &this->index_);
}


template<class T>
Local<T> Eternal<T>::Get(Isolate* isolate) {
  return Local<T>(reinterpret_cast<T*>(*V8::GetEternal(isolate, index_)));
}


template <class T>
T* PersistentBase<T>::New(Isolate* isolate, T* that) {
  if (that == NULL) return NULL;
  internal::Object** p = reinterpret_cast<internal::Object**>(that);
  return reinterpret_cast<T*>(
      V8::GlobalizeReference(reinterpret_cast<internal::Isolate*>(isolate),
                             p));
}


template <class T, class M>
template <class S, class M2>
void Persistent<T, M>::Copy(const Persistent<S, M2>& that) {
  TYPE_CHECK(T, S);
  this->Reset();
  if (that.IsEmpty()) return;
  internal::Object** p = reinterpret_cast<internal::Object**>(that.val_);
  this->val_ = reinterpret_cast<T*>(V8::CopyPersistent(p));
  M::Copy(that, this);
}


template <class T>
bool PersistentBase<T>::IsIndependent() const {
  typedef internal::Internals I;
  if (this->IsEmpty()) return false;
  return I::GetNodeFlag(reinterpret_cast<internal::Object**>(this->val_),
                        I::kNodeIsIndependentShift);
}


template <class T>
bool PersistentBase<T>::IsNearDeath() const {
  typedef internal::Internals I;
  if (this->IsEmpty()) return false;
  uint8_t node_state =
      I::GetNodeState(reinterpret_cast<internal::Object**>(this->val_));
  return node_state == I::kNodeStateIsNearDeathValue ||
      node_state == I::kNodeStateIsPendingValue;
}


template <class T>
bool PersistentBase<T>::IsWeak() const {
  typedef internal::Internals I;
  if (this->IsEmpty()) return false;
  return I::GetNodeState(reinterpret_cast<internal::Object**>(this->val_)) ==
      I::kNodeStateIsWeakValue;
}


template <class T>
void PersistentBase<T>::Reset() {
  if (this->IsEmpty()) return;
  V8::DisposeGlobal(reinterpret_cast<internal::Object**>(this->val_));
  val_ = 0;
}


template <class T>
template <class S>
void PersistentBase<T>::Reset(Isolate* isolate, const Handle<S>& other) {
  TYPE_CHECK(T, S);
  Reset();
  if (other.IsEmpty()) return;
  this->val_ = New(isolate, other.val_);
}


template <class T>
template <class S>
void PersistentBase<T>::Reset(Isolate* isolate,
                              const PersistentBase<S>& other) {
  TYPE_CHECK(T, S);
  Reset();
  if (other.IsEmpty()) return;
  this->val_ = New(isolate, other.val_);
}


template <class T>
template <typename S, typename P>
void PersistentBase<T>::SetWeak(
    P* parameter,
    typename WeakCallbackData<S, P>::Callback callback) {
  TYPE_CHECK(S, T);
  typedef typename WeakCallbackData<Value, void>::Callback Callback;
  V8::MakeWeak(reinterpret_cast<internal::Object**>(this->val_),
               parameter,
               reinterpret_cast<Callback>(callback));
}


template <class T>
template <typename P>
void PersistentBase<T>::SetWeak(
    P* parameter,
    typename WeakCallbackData<T, P>::Callback callback) {
  SetWeak<T, P>(parameter, callback);
}


template <class T>
template<typename P>
P* PersistentBase<T>::ClearWeak() {
  return reinterpret_cast<P*>(
    V8::ClearWeak(reinterpret_cast<internal::Object**>(this->val_)));
}


template <class T>
void PersistentBase<T>::MarkIndependent() {
  typedef internal::Internals I;
  if (this->IsEmpty()) return;
  I::UpdateNodeFlag(reinterpret_cast<internal::Object**>(this->val_),
                    true,
                    I::kNodeIsIndependentShift);
}


template <class T>
void PersistentBase<T>::MarkPartiallyDependent() {
  typedef internal::Internals I;
  if (this->IsEmpty()) return;
  I::UpdateNodeFlag(reinterpret_cast<internal::Object**>(this->val_),
                    true,
                    I::kNodeIsPartiallyDependentShift);
}


template <class T, class M>
T* Persistent<T, M>::ClearAndLeak() {
  T* old;
  old = this->val_;
  this->val_ = NULL;
  return old;
}


template <class T>
void PersistentBase<T>::SetWrapperClassId(uint16_t class_id) {
  typedef internal::Internals I;
  if (this->IsEmpty()) return;
  internal::Object** obj = reinterpret_cast<internal::Object**>(this->val_);
  uint8_t* addr = reinterpret_cast<uint8_t*>(obj) + I::kNodeClassIdOffset;
  *reinterpret_cast<uint16_t*>(addr) = class_id;
}


template <class T>
uint16_t PersistentBase<T>::WrapperClassId() const {
  typedef internal::Internals I;
  if (this->IsEmpty()) return 0;
  internal::Object** obj = reinterpret_cast<internal::Object**>(this->val_);
  uint8_t* addr = reinterpret_cast<uint8_t*>(obj) + I::kNodeClassIdOffset;
  return *reinterpret_cast<uint16_t*>(addr);
}


template<typename T>
ReturnValue<T>::ReturnValue(internal::Object** slot) : value_(slot) {}

template<typename T>
template<typename S>
void ReturnValue<T>::Set(const Persistent<S>& handle) {
  TYPE_CHECK(T, S);
  if (V8_UNLIKELY(handle.IsEmpty())) {
    *value_ = GetDefaultValue();
  } else {
    *value_ = *reinterpret_cast<internal::Object**>(*handle);
  }
}

template<typename T>
template<typename S>
void ReturnValue<T>::Set(const Handle<S> handle) {
  TYPE_CHECK(T, S);
  if (V8_UNLIKELY(handle.IsEmpty())) {
    *value_ = GetDefaultValue();
  } else {
    *value_ = *reinterpret_cast<internal::Object**>(*handle);
  }
}

template<typename T>
void ReturnValue<T>::Set(double i) {
  TYPE_CHECK(T, Number);
  Set(Number::New(GetIsolate(), i));
}

template<typename T>
void ReturnValue<T>::Set(int32_t i) {
  TYPE_CHECK(T, Integer);
  typedef internal::Internals I;
  if (V8_LIKELY(I::IsValidSmi(i))) {
    *value_ = I::IntToSmi(i);
    return;
  }
  Set(Integer::New(GetIsolate(), i));
}

template<typename T>
void ReturnValue<T>::Set(uint32_t i) {
  TYPE_CHECK(T, Integer);
  // Can't simply use INT32_MAX here for whatever reason.
  bool fits_into_int32_t = (i & (1U << 31)) == 0;
  if (V8_LIKELY(fits_into_int32_t)) {
    Set(static_cast<int32_t>(i));
    return;
  }
  Set(Integer::NewFromUnsigned(GetIsolate(), i));
}

template<typename T>
void ReturnValue<T>::Set(bool value) {
  TYPE_CHECK(T, Boolean);
  typedef internal::Internals I;
  int root_index;
  if (value) {
    root_index = I::kTrueValueRootIndex;
  } else {
    root_index = I::kFalseValueRootIndex;
  }
  *value_ = *I::GetRoot(GetIsolate(), root_index);
}

template<typename T>
void ReturnValue<T>::SetNull() {
  TYPE_CHECK(T, Primitive);
  typedef internal::Internals I;
  *value_ = *I::GetRoot(GetIsolate(), I::kNullValueRootIndex);
}

template<typename T>
void ReturnValue<T>::SetUndefined() {
  TYPE_CHECK(T, Primitive);
  typedef internal::Internals I;
  *value_ = *I::GetRoot(GetIsolate(), I::kUndefinedValueRootIndex);
}

template<typename T>
void ReturnValue<T>::SetEmptyString() {
  TYPE_CHECK(T, String);
  typedef internal::Internals I;
  *value_ = *I::GetRoot(GetIsolate(), I::kEmptyStringRootIndex);
}

template<typename T>
Isolate* ReturnValue<T>::GetIsolate() {
  // Isolate is always the pointer below the default value on the stack.
  return *reinterpret_cast<Isolate**>(&value_[-2]);
}

template<typename T>
internal::Object* ReturnValue<T>::GetDefaultValue() {
  // Default value is always the pointer below value_ on the stack.
  return value_[-1];
}


template<typename T>
FunctionCallbackInfo<T>::FunctionCallbackInfo(internal::Object** implicit_args,
                                              internal::Object** values,
                                              int length,
                                              bool is_construct_call)
    : implicit_args_(implicit_args),
      values_(values),
      length_(length),
      is_construct_call_(is_construct_call) { }


template<typename T>
Local<Value> FunctionCallbackInfo<T>::operator[](int i) const {
  if (i < 0 || length_ <= i) return Local<Value>(*Undefined(GetIsolate()));
  return Local<Value>(reinterpret_cast<Value*>(values_ - i));
}


template<typename T>
Local<Function> FunctionCallbackInfo<T>::Callee() const {
  return Local<Function>(reinterpret_cast<Function*>(
      &implicit_args_[kCalleeIndex]));
}


template<typename T>
Local<Object> FunctionCallbackInfo<T>::This() const {
  return Local<Object>(reinterpret_cast<Object*>(values_ + 1));
}


template<typename T>
Local<Object> FunctionCallbackInfo<T>::Holder() const {
  return Local<Object>(reinterpret_cast<Object*>(
      &implicit_args_[kHolderIndex]));
}


template<typename T>
Local<Value> FunctionCallbackInfo<T>::Data() const {
  return Local<Value>(reinterpret_cast<Value*>(&implicit_args_[kDataIndex]));
}


template<typename T>
Isolate* FunctionCallbackInfo<T>::GetIsolate() const {
  return *reinterpret_cast<Isolate**>(&implicit_args_[kIsolateIndex]);
}


template<typename T>
ReturnValue<T> FunctionCallbackInfo<T>::GetReturnValue() const {
  return ReturnValue<T>(&implicit_args_[kReturnValueIndex]);
}


template<typename T>
bool FunctionCallbackInfo<T>::IsConstructCall() const {
  return is_construct_call_;
}


template<typename T>
int FunctionCallbackInfo<T>::Length() const {
  return length_;
}


Handle<Value> ScriptOrigin::ResourceName() const {
  return resource_name_;
}


Handle<Integer> ScriptOrigin::ResourceLineOffset() const {
  return resource_line_offset_;
}


Handle<Integer> ScriptOrigin::ResourceColumnOffset() const {
  return resource_column_offset_;
}

Handle<Boolean> ScriptOrigin::ResourceIsSharedCrossOrigin() const {
  return resource_is_shared_cross_origin_;
}


ScriptCompiler::Source::Source(Local<String> string, const ScriptOrigin& origin,
                               CachedData* data)
    : source_string(string),
      resource_name(origin.ResourceName()),
      resource_line_offset(origin.ResourceLineOffset()),
      resource_column_offset(origin.ResourceColumnOffset()),
      resource_is_shared_cross_origin(origin.ResourceIsSharedCrossOrigin()),
      cached_data(data) {}


ScriptCompiler::Source::Source(Local<String> string,
                               CachedData* data)
    : source_string(string), cached_data(data) {}


ScriptCompiler::Source::~Source() {
  delete cached_data;
}


const ScriptCompiler::CachedData* ScriptCompiler::Source::GetCachedData()
    const {
  return cached_data;
}


Handle<Boolean> Boolean::New(Isolate* isolate, bool value) {
  return value ? True(isolate) : False(isolate);
}


void Template::Set(Isolate* isolate, const char* name, v8::Handle<Data> value) {
  Set(v8::String::NewFromUtf8(isolate, name), value);
}


Local<Value> Object::GetInternalField(int index) {
#ifndef V8_ENABLE_CHECKS
  typedef internal::Object O;
  typedef internal::HeapObject HO;
  typedef internal::Internals I;
  O* obj = *reinterpret_cast<O**>(this);
  // Fast path: If the object is a plain JSObject, which is the common case, we
  // know where to find the internal fields and can return the value directly.
  if (I::GetInstanceType(obj) == I::kJSObjectType) {
    int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
    O* value = I::ReadField<O*>(obj, offset);
    O** result = HandleScope::CreateHandle(reinterpret_cast<HO*>(obj), value);
    return Local<Value>(reinterpret_cast<Value*>(result));
  }
#endif
  return SlowGetInternalField(index);
}


void* Object::GetAlignedPointerFromInternalField(int index) {
#ifndef V8_ENABLE_CHECKS
  typedef internal::Object O;
  typedef internal::Internals I;
  O* obj = *reinterpret_cast<O**>(this);
  // Fast path: If the object is a plain JSObject, which is the common case, we
  // know where to find the internal fields and can return the value directly.
  if (V8_LIKELY(I::GetInstanceType(obj) == I::kJSObjectType)) {
    int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
    return I::ReadField<void*>(obj, offset);
  }
#endif
  return SlowGetAlignedPointerFromInternalField(index);
}


String* String::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<String*>(value);
}


Local<String> String::Empty(Isolate* isolate) {
  typedef internal::Object* S;
  typedef internal::Internals I;
  I::CheckInitialized(isolate);
  S* slot = I::GetRoot(isolate, I::kEmptyStringRootIndex);
  return Local<String>(reinterpret_cast<String*>(slot));
}


String::ExternalStringResource* String::GetExternalStringResource() const {
  typedef internal::Object O;
  typedef internal::Internals I;
  O* obj = *reinterpret_cast<O**>(const_cast<String*>(this));
  String::ExternalStringResource* result;
  if (I::IsExternalTwoByteString(I::GetInstanceType(obj))) {
    void* value = I::ReadField<void*>(obj, I::kStringResourceOffset);
    result = reinterpret_cast<String::ExternalStringResource*>(value);
  } else {
    result = NULL;
  }
#ifdef V8_ENABLE_CHECKS
  VerifyExternalStringResource(result);
#endif
  return result;
}


String::ExternalStringResourceBase* String::GetExternalStringResourceBase(
    String::Encoding* encoding_out) const {
  typedef internal::Object O;
  typedef internal::Internals I;
  O* obj = *reinterpret_cast<O**>(const_cast<String*>(this));
  int type = I::GetInstanceType(obj) & I::kFullStringRepresentationMask;
  *encoding_out = static_cast<Encoding>(type & I::kStringEncodingMask);
  ExternalStringResourceBase* resource = NULL;
  if (type == I::kExternalAsciiRepresentationTag ||
      type == I::kExternalTwoByteRepresentationTag) {
    void* value = I::ReadField<void*>(obj, I::kStringResourceOffset);
    resource = static_cast<ExternalStringResourceBase*>(value);
  }
#ifdef V8_ENABLE_CHECKS
    VerifyExternalStringResourceBase(resource, *encoding_out);
#endif
  return resource;
}


bool Value::IsUndefined() const {
#ifdef V8_ENABLE_CHECKS
  return FullIsUndefined();
#else
  return QuickIsUndefined();
#endif
}

bool Value::QuickIsUndefined() const {
  typedef internal::Object O;
  typedef internal::Internals I;
  O* obj = *reinterpret_cast<O**>(const_cast<Value*>(this));
  if (!I::HasHeapObjectTag(obj)) return false;
  if (I::GetInstanceType(obj) != I::kOddballType) return false;
  return (I::GetOddballKind(obj) == I::kUndefinedOddballKind);
}


bool Value::IsNull() const {
#ifdef V8_ENABLE_CHECKS
  return FullIsNull();
#else
  return QuickIsNull();
#endif
}

bool Value::QuickIsNull() const {
  typedef internal::Object O;
  typedef internal::Internals I;
  O* obj = *reinterpret_cast<O**>(const_cast<Value*>(this));
  if (!I::HasHeapObjectTag(obj)) return false;
  if (I::GetInstanceType(obj) != I::kOddballType) return false;
  return (I::GetOddballKind(obj) == I::kNullOddballKind);
}


bool Value::IsString() const {
#ifdef V8_ENABLE_CHECKS
  return FullIsString();
#else
  return QuickIsString();
#endif
}

bool Value::QuickIsString() const {
  typedef internal::Object O;
  typedef internal::Internals I;
  O* obj = *reinterpret_cast<O**>(const_cast<Value*>(this));
  if (!I::HasHeapObjectTag(obj)) return false;
  return (I::GetInstanceType(obj) < I::kFirstNonstringType);
}


template <class T> Value* Value::Cast(T* value) {
  return static_cast<Value*>(value);
}


Symbol* Symbol::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Symbol*>(value);
}


Number* Number::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Number*>(value);
}


Integer* Integer::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Integer*>(value);
}


Date* Date::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Date*>(value);
}


StringObject* StringObject::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<StringObject*>(value);
}


SymbolObject* SymbolObject::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<SymbolObject*>(value);
}


NumberObject* NumberObject::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<NumberObject*>(value);
}


BooleanObject* BooleanObject::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<BooleanObject*>(value);
}


RegExp* RegExp::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<RegExp*>(value);
}


Object* Object::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Object*>(value);
}


Array* Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Array*>(value);
}


Promise* Promise::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Promise*>(value);
}


Promise::Resolver* Promise::Resolver::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Promise::Resolver*>(value);
}


ArrayBuffer* ArrayBuffer::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<ArrayBuffer*>(value);
}


ArrayBufferView* ArrayBufferView::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<ArrayBufferView*>(value);
}


TypedArray* TypedArray::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<TypedArray*>(value);
}


Uint8Array* Uint8Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Uint8Array*>(value);
}


Int8Array* Int8Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Int8Array*>(value);
}


Uint16Array* Uint16Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Uint16Array*>(value);
}


Int16Array* Int16Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Int16Array*>(value);
}


Uint32Array* Uint32Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Uint32Array*>(value);
}


Int32Array* Int32Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Int32Array*>(value);
}


Float32Array* Float32Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Float32Array*>(value);
}


Float64Array* Float64Array::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Float64Array*>(value);
}


Uint8ClampedArray* Uint8ClampedArray::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Uint8ClampedArray*>(value);
}


DataView* DataView::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<DataView*>(value);
}


Function* Function::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<Function*>(value);
}


External* External::Cast(v8::Value* value) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(value);
#endif
  return static_cast<External*>(value);
}


template<typename T>
Isolate* PropertyCallbackInfo<T>::GetIsolate() const {
  return *reinterpret_cast<Isolate**>(&args_[kIsolateIndex]);
}


template<typename T>
Local<Value> PropertyCallbackInfo<T>::Data() const {
  return Local<Value>(reinterpret_cast<Value*>(&args_[kDataIndex]));
}


template<typename T>
Local<Object> PropertyCallbackInfo<T>::This() const {
  return Local<Object>(reinterpret_cast<Object*>(&args_[kThisIndex]));
}


template<typename T>
Local<Object> PropertyCallbackInfo<T>::Holder() const {
  return Local<Object>(reinterpret_cast<Object*>(&args_[kHolderIndex]));
}


template<typename T>
ReturnValue<T> PropertyCallbackInfo<T>::GetReturnValue() const {
  return ReturnValue<T>(&args_[kReturnValueIndex]);
}


Handle<Primitive> Undefined(Isolate* isolate) {
  typedef internal::Object* S;
  typedef internal::Internals I;
  I::CheckInitialized(isolate);
  S* slot = I::GetRoot(isolate, I::kUndefinedValueRootIndex);
  return Handle<Primitive>(reinterpret_cast<Primitive*>(slot));
}


Handle<Primitive> Null(Isolate* isolate) {
  typedef internal::Object* S;
  typedef internal::Internals I;
  I::CheckInitialized(isolate);
  S* slot = I::GetRoot(isolate, I::kNullValueRootIndex);
  return Handle<Primitive>(reinterpret_cast<Primitive*>(slot));
}


Handle<Boolean> True(Isolate* isolate) {
  typedef internal::Object* S;
  typedef internal::Internals I;
  I::CheckInitialized(isolate);
  S* slot = I::GetRoot(isolate, I::kTrueValueRootIndex);
  return Handle<Boolean>(reinterpret_cast<Boolean*>(slot));
}


Handle<Boolean> False(Isolate* isolate) {
  typedef internal::Object* S;
  typedef internal::Internals I;
  I::CheckInitialized(isolate);
  S* slot = I::GetRoot(isolate, I::kFalseValueRootIndex);
  return Handle<Boolean>(reinterpret_cast<Boolean*>(slot));
}


void Isolate::SetData(uint32_t slot, void* data) {
  typedef internal::Internals I;
  I::SetEmbedderData(this, slot, data);
}


void* Isolate::GetData(uint32_t slot) {
  typedef internal::Internals I;
  return I::GetEmbedderData(this, slot);
}


uint32_t Isolate::GetNumberOfDataSlots() {
  typedef internal::Internals I;
  return I::kNumIsolateDataSlots;
}


template<typename T>
void Isolate::SetObjectGroupId(const Persistent<T>& object,
                               UniqueId id) {
  TYPE_CHECK(Value, T);
  SetObjectGroupId(reinterpret_cast<v8::internal::Object**>(object.val_), id);
}


template<typename T>
void Isolate::SetReferenceFromGroup(UniqueId id,
                                    const Persistent<T>& object) {
  TYPE_CHECK(Value, T);
  SetReferenceFromGroup(id,
                        reinterpret_cast<v8::internal::Object**>(object.val_));
}


template<typename T, typename S>
void Isolate::SetReference(const Persistent<T>& parent,
                           const Persistent<S>& child) {
  TYPE_CHECK(Object, T);
  TYPE_CHECK(Value, S);
  SetReference(reinterpret_cast<v8::internal::Object**>(parent.val_),
               reinterpret_cast<v8::internal::Object**>(child.val_));
}


Local<Value> Context::GetEmbedderData(int index) {
#ifndef V8_ENABLE_CHECKS
  typedef internal::Object O;
  typedef internal::HeapObject HO;
  typedef internal::Internals I;
  HO* context = *reinterpret_cast<HO**>(this);
  O** result =
      HandleScope::CreateHandle(context, I::ReadEmbedderData<O*>(this, index));
  return Local<Value>(reinterpret_cast<Value*>(result));
#else
  return SlowGetEmbedderData(index);
#endif
}


void* Context::GetAlignedPointerFromEmbedderData(int index) {
#ifndef V8_ENABLE_CHECKS
  typedef internal::Internals I;
  return I::ReadEmbedderData<void*>(this, index);
#else
  return SlowGetAlignedPointerFromEmbedderData(index);
#endif
}


}  // namespace v8


#undef TYPE_CHECK


#endif  // V8_H_