First cut at impementing ES6 TypedArrays in V8.

src/objects.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 39 matching lines @@
 // Inheritance hierarchy:
 // - MaybeObject    (an object or a failure)
 //   - Failure      (immediate for marking failed operation)
 //   - Object
 //     - Smi          (immediate small integer)
 //     - HeapObject   (superclass for everything allocated in the heap)
 //       - JSReceiver  (suitable for property access)
 //         - JSObject
 //           - JSArray
 //           - JSArrayBuffer
+//           - JSTypedArray
 //           - JSSet
 //           - JSMap
 //           - JSWeakMap
 //           - JSRegExp
 //           - JSFunction
 //           - JSModule
 //           - GlobalObject
 //             - JSGlobalObject
 //             - JSBuiltinsObject
 //           - JSGlobalProxy
@@ skipping 324 matching lines @@
   V(JS_VALUE_TYPE)                                                             \
   V(JS_DATE_TYPE)                                                              \
   V(JS_OBJECT_TYPE)                                                            \
   V(JS_CONTEXT_EXTENSION_OBJECT_TYPE)                                          \
   V(JS_MODULE_TYPE)                                                            \
   V(JS_GLOBAL_OBJECT_TYPE)                                                     \
   V(JS_BUILTINS_OBJECT_TYPE)                                                   \
   V(JS_GLOBAL_PROXY_TYPE)                                                      \
   V(JS_ARRAY_TYPE)                                                             \
   V(JS_ARRAY_BUFFER_TYPE)                                                      \
+  V(JS_TYPED_ARRAY_TYPE)                                                       \
   V(JS_PROXY_TYPE)                                                             \
   V(JS_WEAK_MAP_TYPE)                                                          \
   V(JS_REGEXP_TYPE)                                                            \
                                                                                \
   V(JS_FUNCTION_TYPE)                                                          \
   V(JS_FUNCTION_PROXY_TYPE)                                                    \
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
 #define INSTANCE_TYPE_LIST_DEBUGGER(V)                                         \
   V(DEBUG_INFO_TYPE)                                                           \
@@ skipping 311 matching lines @@
   JS_VALUE_TYPE,  // FIRST_JS_OBJECT_TYPE
   JS_DATE_TYPE,
   JS_OBJECT_TYPE,
   JS_CONTEXT_EXTENSION_OBJECT_TYPE,
   JS_MODULE_TYPE,
   JS_GLOBAL_OBJECT_TYPE,
   JS_BUILTINS_OBJECT_TYPE,
   JS_GLOBAL_PROXY_TYPE,
   JS_ARRAY_TYPE,
   JS_ARRAY_BUFFER_TYPE,
+  JS_TYPED_ARRAY_TYPE,
   JS_SET_TYPE,
   JS_MAP_TYPE,
   JS_WEAK_MAP_TYPE,
 
   JS_REGEXP_TYPE,
 
   JS_FUNCTION_TYPE,  // LAST_JS_OBJECT_TYPE, LAST_JS_RECEIVER_TYPE
 
   // Pseudo-types
   FIRST_TYPE = 0x0,
@@ skipping 226 matching lines @@
   V(Oddball)                                   \
   V(SharedFunctionInfo)                        \
   V(JSValue)                                   \
   V(JSDate)                                    \
   V(JSMessageObject)                           \
   V(StringWrapper)                             \
   V(Foreign)                                   \
   V(Boolean)                                   \
   V(JSArray)                                   \
   V(JSArrayBuffer)                             \
+  V(JSTypedArray)                              \
   V(JSProxy)                                   \
   V(JSFunctionProxy)                           \
   V(JSSet)                                     \
   V(JSMap)                                     \
   V(JSWeakMap)                                 \
   V(JSRegExp)                                  \
   V(HashTable)                                 \
   V(Dictionary)                                \
   V(StringTable)                               \
   V(JSFunctionResultCache)                     \
@@ skipping 7523 matching lines @@
 
   static const int kBackingStoreOffset = JSObject::kHeaderSize;
   static const int kByteLengthOffset = kBackingStoreOffset + kPointerSize;
   static const int kSize = kByteLengthOffset + kPointerSize;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSArrayBuffer);
 };
 
 
+class JSTypedArray: public JSObject {
+ public:
+  // [buffer]: ArrayBuffer that this typed array views.
+  DECL_ACCESSORS(buffer, Object)
+
+  // [byte_length]: offset of typed array in bytes.
+  DECL_ACCESSORS(byte_offset, Object)
+
+  // [byte_length]: length of typed array in bytes.
+  DECL_ACCESSORS(byte_length, Object)
+
+  // [length]: length of typed array in elements.
+  DECL_ACCESSORS(length, Object)
+
+  // Casting.
+  static inline JSTypedArray* cast(Object* obj);
+
+  // Dispatched behavior.
+  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 kSize = kLengthOffset + kPointerSize;
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(JSTypedArray);
+};
+
+
 // 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.
 class Foreign: public HeapObject {
  public:
   // [address]: field containing the address.
   inline Address foreign_address();
   inline void set_foreign_address(Address value);
 
   // Casting.
@@ skipping 784 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_