DataView implementation.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index c256a7cd9c6cb30c2f435cb93285103d96be3758..ceffd83a8022647a148236fcc59e69d533d22ab3 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -408,6 +408,7 @@ const int kStubMinorKeyBits = kBitsPerInt - kSmiTagSize - kStubMajorKeyBits;
   V(JS_ARRAY_TYPE)                                                             \
   V(JS_ARRAY_BUFFER_TYPE)                                                      \
   V(JS_TYPED_ARRAY_TYPE)                                                       \
+  V(JS_DATA_VIEW_TYPE)                                                         \
   V(JS_PROXY_TYPE)                                                             \
   V(JS_WEAK_MAP_TYPE)                                                          \
   V(JS_REGEXP_TYPE)                                                            \
@@ -744,6 +745,7 @@ enum InstanceType {
   JS_ARRAY_TYPE,
   JS_ARRAY_BUFFER_TYPE,
   JS_TYPED_ARRAY_TYPE,
+  JS_DATA_VIEW_TYPE,
   JS_SET_TYPE,
   JS_MAP_TYPE,
   JS_WEAK_MAP_TYPE,
@@ -993,7 +995,9 @@ class MaybeObject BASE_EMBEDDED {
   V(Boolean)                                   \
   V(JSArray)                                   \
   V(JSArrayBuffer)                             \
+  V(JSArrayBufferView)                         \

[rossberg, 2013/06/21 08:44:01]

Please add the new classes to the hierarchy comment near the top of the file

[Dmitry Lomov (no reviews), 2013/06/21 11:32:10]

Done.

   V(JSTypedArray)                              \
+  V(JSDataView)                                \
   V(JSProxy)                                   \
   V(JSFunctionProxy)                           \
   V(JSSet)                                     \
@@ -8841,7 +8845,7 @@ class JSArrayBuffer: public JSObject {
 };
 
 
-class JSTypedArray: public JSObject {
+class JSArrayBufferView: public JSObject {
  public:
   // [buffer]: ArrayBuffer that this typed array views.
   DECL_ACCESSORS(buffer, Object)
@@ -8852,12 +8856,33 @@ class JSTypedArray: public JSObject {
   // [byte_length]: length of typed array in bytes.
   DECL_ACCESSORS(byte_length, Object)
 
-  // [length]: length of typed array in elements.
-  DECL_ACCESSORS(length, Object)
-
   // [weak_next]: linked list of typed arrays over the same array buffer.
   DECL_ACCESSORS(weak_next, Object)
 
+  // Casting.
+  static inline JSArrayBufferView* cast(Object* obj);
+
+  DECLARE_VERIFIER(JSArrayBufferView);
+
+  static const int kBufferOffset = JSObject::kHeaderSize;
+  static const int kByteOffsetOffset = kBufferOffset + kPointerSize;
+  static const int kByteLengthOffset = kByteOffsetOffset + kPointerSize;
+  static const int kWeakNextOffset = kByteLengthOffset + kPointerSize;
+  static const int kViewSize = kWeakNextOffset + kPointerSize;
+
+ protected:
+  void NeuterView();
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(JSArrayBufferView);
+};
+
+
+class JSTypedArray: public JSArrayBufferView {
+ public:
+  // [length]: length of typed array in elements.
+  DECL_ACCESSORS(length, Object)
+
   // Neutering. Only neuters this typed array.
   void Neuter();
 
@@ -8871,18 +8896,33 @@ class JSTypedArray: public JSObject {
   DECLARE_PRINTER(JSTypedArray)
   DECLARE_VERIFIER(JSTypedArray)
 
-  static const int kBufferOffset = JSObject::kHeaderSize;
-  static const int kByteOffsetOffset = kBufferOffset + kPointerSize;
-  static const int kByteLengthOffset = kByteOffsetOffset + kPointerSize;
-  static const int kLengthOffset = kByteLengthOffset + kPointerSize;
-  static const int kWeakNextOffset = kLengthOffset + kPointerSize;
-  static const int kSize = kWeakNextOffset + kPointerSize;
+  static const int kLengthOffset = kViewSize + kPointerSize;
+  static const int kSize = kLengthOffset + kPointerSize;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSTypedArray);
 };
 
 
+class JSDataView: public JSArrayBufferView {
+ public:
+  // Only neuters this DataView
+  void Neuter();
+
+  // Casting.
+  static inline JSDataView* cast(Object* obj);
+
+  // Dispatched behavior.
+  DECLARE_PRINTER(JSDataView)
+  DECLARE_VERIFIER(JSDataView)
+
+  static const int kSize = kViewSize;
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(JSDataView);
+};
+
+
 // Foreign describes objects pointing from JavaScript to C structures.
 // Since they cannot contain references to JS HeapObjects they can be
 // placed in old_data_space.