Rollback of r12868, r12849 on bleeding_edge.

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 28bea2e3e4435b39a4b50a140513560b80b3fd85..cf9275d918ccadc9dda2735069f1182a206cd874 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -76,17 +76,6 @@
 
 #endif  // _WIN32
 
-// TODO(svenpanne) Remove this when the Chrome's v8 bindings have been adapted.
-#define V8_DISABLE_DEPRECATIONS 1
-
-#if defined(__GNUC__) && !defined(V8_DISABLE_DEPRECATIONS)
-#define V8_DEPRECATED(func) func __attribute__ ((deprecated))
-#elif defined(_MSC_VER) && !defined(V8_DISABLE_DEPRECATIONS)
-#define V8_DEPRECATED(func) __declspec(deprecated) func
-#else
-#define V8_DEPRECATED(func) func
-#endif
-
 /**
  * The v8 JavaScript engine.
  */
@@ -1612,41 +1601,16 @@ class Object : public Value {
 
   /** Gets the number of internal fields for this Object. */
   V8EXPORT int InternalFieldCount();
-
-  /** Gets the value from an internal field. */
+  /** Gets the value in an internal field. */
   inline Local<Value> GetInternalField(int index);
-
   /** Sets the value in an internal field. */
   V8EXPORT void SetInternalField(int index, Handle<Value> value);
 
-  /**
-   * Gets a native pointer from an internal field. Deprecated. If the pointer is
-   * always 2-byte-aligned, use GetAlignedPointerFromInternalField instead,
-   * otherwise use a combination of GetInternalField, External::Cast and
-   * External::Value.
-   */
-  V8EXPORT V8_DEPRECATED(void* GetPointerFromInternalField(int index));
-
-  /**
-   * Sets a native pointer in an internal field. Deprecated. If the pointer is
-   * always 2-byte aligned, use SetAlignedPointerInInternalField instead,
-   * otherwise use a combination of External::New and SetInternalField.
-   */
-  inline V8_DEPRECATED(void SetPointerInInternalField(int index, void* value));
+  /** Gets a native pointer from an internal field. */
+  inline void* GetPointerFromInternalField(int index);
 
-  /**
-   * Gets a 2-byte-aligned native pointer from an internal field. This field
-   * must have been set by SetAlignedPointerInInternalField, everything else
-   * leads to undefined behavior.
-   */
-  inline void* GetAlignedPointerFromInternalField(int index);
-
-  /**
-   * Sets a 2-byte-aligned native pointer in an internal field. To retrieve such
-   * a field, GetAlignedPointerFromInternalField must be used, everything else
-   * leads to undefined behavior.
-   */
-  V8EXPORT void SetAlignedPointerInInternalField(int index, void* value);
+  /** Sets a native pointer in an internal field. */
+  V8EXPORT void SetPointerInInternalField(int index, void* value);
 
   // Testers for local properties.
   V8EXPORT bool HasOwnProperty(Handle<String> key);
@@ -1777,8 +1741,14 @@ class Object : public Value {
  private:
   V8EXPORT Object();
   V8EXPORT static void CheckCast(Value* obj);
-  V8EXPORT Local<Value> SlowGetInternalField(int index);
-  V8EXPORT void* SlowGetAlignedPointerFromInternalField(int index);
+  V8EXPORT Local<Value> CheckedGetInternalField(int index);
+  V8EXPORT void* SlowGetPointerFromInternalField(int index);
+
+  /**
+   * If quick access to the internal field is possible this method
+   * returns the value.  Otherwise an empty handle is returned.
+   */
+  inline Local<Value> UncheckedGetInternalField(int index);
 };
 
 
@@ -1989,22 +1959,29 @@ class RegExp : public Object {
 
 
 /**
- * A JavaScript value that wraps a C++ void*. This type of value is mainly used
- * to associate C++ data structures with JavaScript objects.
+ * A JavaScript value that wraps a C++ void*.  This type of value is
+ * mainly used to associate C++ data structures with JavaScript
+ * objects.
+ *
+ * The Wrap function V8 will return the most optimal Value object wrapping the
+ * C++ void*. The type of the value is not guaranteed to be an External object
+ * and no assumptions about its type should be made. To access the wrapped
+ * value Unwrap should be used, all other operations on that object will lead
+ * to unpredictable results.
  */
 class External : public Value {
  public:
-  /** Deprecated, use New instead. */
-  V8_DEPRECATED(static inline Local<Value> Wrap(void* value));
-
-  /** Deprecated, use a combination of Cast and Value instead. */
-  V8_DEPRECATED(static inline void* Unwrap(Handle<Value> obj));
+  V8EXPORT static Local<Value> Wrap(void* data);
+  static inline void* Unwrap(Handle<Value> obj);
 
   V8EXPORT static Local<External> New(void* value);
   static inline External* Cast(Value* obj);
   V8EXPORT void* Value() const;
  private:
+  V8EXPORT External();
   V8EXPORT static void CheckCast(v8::Value* obj);
+  static inline void* QuickUnwrap(Handle<v8::Value> obj);
+  V8EXPORT static void* FullUnwrap(Handle<v8::Value> obj);
 };
 
 
@@ -3793,45 +3770,12 @@ class V8EXPORT Context {
   static bool InContext();
 
   /**
-   * Gets embedder data with index 0. Deprecated, use GetEmbedderData with index
-   * 0 instead.
-   */
-  V8_DEPRECATED(inline Local<Value> GetData());
-
-  /**
-   * Sets embedder data with index 0. Deprecated, use SetEmbedderData with index
-   * 0 instead.
+   * Associate an additional data object with the context. This is mainly used
+   * with the debugger to provide additional information on the context through
+   * the debugger API.
    */
-  V8_DEPRECATED(inline void SetData(Handle<Value> value));
-
-  /**
-   * Gets the embedder data with the given index, which must have been set by a
-   * previous call to SetEmbedderData with the same index. Note that index 0
-   * currently has a special meaning for Chrome's debugger.
-   */
-  inline Local<Value> GetEmbedderData(int index);
-
-  /**
-   * Sets the embedder data with the given index, growing the data as
-   * needed. Note that index 0 currently has a special meaning for Chrome's
-   * debugger.
-   */
-  void SetEmbedderData(int index, Handle<Value> value);
-
-  /**
-   * Gets a 2-byte-aligned native pointer from the embedder data with the given
-   * index, which must have bees set by a previous call to
-   * SetAlignedPointerInEmbedderData with the same index. Note that index 0
-   * currently has a special meaning for Chrome's debugger.
-   */
-  inline void* GetAlignedPointerFromEmbedderData(int index);
-
-  /**
-   * Sets a 2-byte-aligned native pointer in the embedder data with the given
-   * index, growing the data as needed. Note that index 0 currently has a
-   * special meaning for Chrome's debugger.
-   */
-  void SetAlignedPointerInEmbedderData(int index, void* value);
+  void SetData(Handle<Value> data);
+  Local<Value> GetData();
 
   /**
    * Control whether code generation from strings is allowed. Calling
@@ -3880,9 +3824,6 @@ class V8EXPORT Context {
   friend class Script;
   friend class Object;
   friend class Function;
-
-  Local<Value> SlowGetEmbedderData(int index);
-  void* SlowGetAlignedPointerFromEmbedderData(int index);
 };
 
 
@@ -4116,6 +4057,11 @@ template <> struct SmiTagging<4> {
     // Throw away top 32 bits and shift down (requires >> to be sign extending).
     return static_cast<int>(reinterpret_cast<intptr_t>(value)) >> shift_bits;
   }
+
+  // For 32-bit systems any 2 bytes aligned pointer can be encoded as smi
+  // with a plain reinterpret_cast.
+  static const uintptr_t kEncodablePointerMask = 0x1;
+  static const int kPointerToSmiShift = 0;
 };
 
 // Smi constants for 64-bit systems.
@@ -4127,11 +4073,26 @@ template <> struct SmiTagging<8> {
     // Shift down and throw away top 32 bits.
     return static_cast<int>(reinterpret_cast<intptr_t>(value) >> shift_bits);
   }
+
+  // To maximize the range of pointers that can be encoded
+  // in the available 32 bits, we require them to be 8 bytes aligned.
+  // This gives 2 ^ (32 + 3) = 32G address space covered.
+  // It might be not enough to cover stack allocated objects on some platforms.
+  static const int kPointerAlignment = 3;
+
+  static const uintptr_t kEncodablePointerMask =
+      ~(uintptr_t(0xffffffff) << kPointerAlignment);
+
+  static const int kPointerToSmiShift =
+      kSmiTagSize + kSmiShiftSize - kPointerAlignment;
 };
 
 typedef SmiTagging<kApiPointerSize> PlatformSmiTagging;
 const int kSmiShiftSize = PlatformSmiTagging::kSmiShiftSize;
 const int kSmiValueSize = PlatformSmiTagging::kSmiValueSize;
+const uintptr_t kEncodablePointerMask =
+    PlatformSmiTagging::kEncodablePointerMask;
+const int kPointerToSmiShift = PlatformSmiTagging::kPointerToSmiShift;
 
 /**
  * This class exports constants and functionality from within v8 that
@@ -4149,9 +4110,6 @@ class Internals {
   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 = 54;
   static const int kFullStringRepresentationMask = 0x07;
   static const int kStringEncodingMask = 0x4;
   static const int kExternalTwoByteRepresentationTag = 0x02;
@@ -4164,7 +4122,7 @@ class Internals {
   static const int kNullValueRootIndex = 7;
   static const int kTrueValueRootIndex = 8;
   static const int kFalseValueRootIndex = 9;
-  static const int kEmptySymbolRootIndex = 119;
+  static const int kEmptySymbolRootIndex = 118;
 
   static const int kJSObjectType = 0xaa;
   static const int kFirstNonstringType = 0x80;
@@ -4179,6 +4137,10 @@ class Internals {
             kHeapObjectTag);
   }
 
+  static inline bool HasSmiTag(internal::Object* value) {
+    return ((reinterpret_cast<intptr_t>(value) & kSmiTagMask) == kSmiTag);
+  }
+
   static inline int SmiValue(internal::Object* value) {
     return PlatformSmiTagging::SmiToInt(value);
   }
@@ -4194,6 +4156,21 @@ class Internals {
     return SmiValue(ReadField<O*>(obj, kOddballKindOffset));
   }
 
+  static inline void* GetExternalPointerFromSmi(internal::Object* value) {
+    const uintptr_t address = reinterpret_cast<uintptr_t>(value);
+    return reinterpret_cast<void*>(address >> kPointerToSmiShift);
+  }
+
+  static inline void* GetExternalPointer(internal::Object* obj) {
+    if (HasSmiTag(obj)) {
+      return GetExternalPointerFromSmi(obj);
+    } else if (GetInstanceType(obj) == kForeignType) {
+      return ReadField<void*>(obj, kForeignAddressOffset);
+    } else {
+      return NULL;
+    }
+  }
+
   static inline bool IsExternalTwoByteString(int instance_type) {
     int representation = (instance_type & kFullStringRepresentationMask);
     return representation == kExternalTwoByteRepresentationTag;
@@ -4227,19 +4204,6 @@ class Internals {
     return *reinterpret_cast<T*>(addr);
   }
 
-  template <typename T>
-  static inline 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);
-  }
-
   static inline bool CanCastToHeapObject(void* o) { return false; }
   static inline bool CanCastToHeapObject(Context* o) { return true; }
   static inline bool CanCastToHeapObject(String* o) { return true; }
@@ -4454,40 +4418,63 @@ void Template::Set(const char* name, v8::Handle<Data> value) {
 
 Local<Value> Object::GetInternalField(int index) {
 #ifndef V8_ENABLE_CHECKS
+  Local<Value> quick_result = UncheckedGetInternalField(index);
+  if (!quick_result.IsEmpty()) return quick_result;
+#endif
+  return CheckedGetInternalField(index);
+}
+
+
+Local<Value> Object::UncheckedGetInternalField(int index) {
   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 (I::GetInstanceType(obj) == I::kJSObjectType) {
+    // 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.
     int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
     O* value = I::ReadField<O*>(obj, offset);
     O** result = HandleScope::CreateHandle(value);
     return Local<Value>(reinterpret_cast<Value*>(result));
+  } else {
+    return Local<Value>();
   }
+}
+
+
+void* External::Unwrap(Handle<v8::Value> obj) {
+#ifdef V8_ENABLE_CHECKS
+  return FullUnwrap(obj);
+#else
+  return QuickUnwrap(obj);
 #endif
-  return SlowGetInternalField(index);
 }
 
 
-void Object::SetPointerInInternalField(int index, void* value) {
-  SetInternalField(index, External::New(value));
+void* External::QuickUnwrap(Handle<v8::Value> wrapper) {
+  typedef internal::Object O;
+  O* obj = *reinterpret_cast<O**>(const_cast<v8::Value*>(*wrapper));
+  return internal::Internals::GetExternalPointer(obj);
 }
 
 
-void* Object::GetAlignedPointerFromInternalField(int index) {
-#ifndef V8_ENABLE_CHECKS
+void* Object::GetPointerFromInternalField(int index) {
   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 (I::GetInstanceType(obj) == I::kJSObjectType) {
+    // 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.
     int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
-    return I::ReadField<void*>(obj, offset);
+    O* value = I::ReadField<O*>(obj, offset);
+    return I::GetExternalPointer(value);
   }
-#endif
-  return SlowGetAlignedPointerFromInternalField(index);
+
+  return SlowGetPointerFromInternalField(index);
 }
 
 
@@ -4679,16 +4666,6 @@ Function* Function::Cast(v8::Value* value) {
 }
 
 
-Local<Value> External::Wrap(void* value) {
-  return External::New(value);
-}
-
-
-void* External::Unwrap(Handle<v8::Value> obj) {
-  return External::Cast(*obj)->Value();
-}
-
-
 External* External::Cast(v8::Value* value) {
 #ifdef V8_ENABLE_CHECKS
   CheckCast(value);
@@ -4765,37 +4742,6 @@ void* Isolate::GetData() {
 }
 
 
-Local<Value> Context::GetData() {
-  return GetEmbedderData(0);
-}
-
-void Context::SetData(Handle<Value> data) {
-  SetEmbedderData(0, data);
-}
-
-
-Local<Value> Context::GetEmbedderData(int index) {
-#ifndef V8_ENABLE_CHECKS
-  typedef internal::Object O;
-  typedef internal::Internals I;
-  O** result = HandleScope::CreateHandle(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
-}
-
-
 /**
  * \example shell.cc
  * A simple shell that takes a list of expressions on the