Use GetProperty for getting elements.

src/runtime/runtime-typedarray.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/arguments.h"
 #include "src/messages.h"
 #include "src/runtime/runtime.h"
 #include "src/runtime/runtime-utils.h"
@@ skipping 260 matching lines @@
   size_t element_size = 1;                            // Bogus initialization.
   ElementsKind external_elements_kind =
       EXTERNAL_INT8_ELEMENTS;                        // Bogus intialization.
   ElementsKind fixed_elements_kind = INT8_ELEMENTS;  // Bogus initialization.
   Runtime::ArrayIdToTypeAndSize(arrayId, &array_type, &external_elements_kind,
                                 &fixed_elements_kind, &element_size);
 
   RUNTIME_ASSERT(holder->map()->elements_kind() == fixed_elements_kind);
 
   Handle<JSArrayBuffer> buffer = isolate->factory()->NewJSArrayBuffer();
+  size_t length = 0;
   if (source->IsJSTypedArray() &&
       JSTypedArray::cast(*source)->type() == array_type) {
-    length_obj = Handle<Object>(JSTypedArray::cast(*source)->length(), isolate);
+    length_obj = handle(JSTypedArray::cast(*source)->length(), isolate);
+    length = JSTypedArray::cast(*source)->length_value();
+  } else {
+    RUNTIME_ASSERT(TryNumberToSize(isolate, *length_obj, &length));
   }
-  size_t length = 0;
-  RUNTIME_ASSERT(TryNumberToSize(isolate, *length_obj, &length));
 
   if ((length > static_cast<unsigned>(Smi::kMaxValue)) ||
       (length > (kMaxInt / element_size))) {
     THROW_NEW_ERROR_RETURN_FAILURE(
         isolate, NewRangeError(MessageTemplate::kInvalidTypedArrayLength));
   }
   size_t byte_length = length * element_size;
 
   DCHECK(holder->GetInternalFieldCount() ==
          v8::ArrayBufferView::kInternalFieldCount);
@@ skipping 51 matching lines @@
     }
   }
 
   return isolate->heap()->false_value();
 }
 
 
 #define BUFFER_VIEW_GETTER(Type, getter, accessor)   \
   RUNTIME_FUNCTION(Runtime_##Type##Get##getter) {    \
     HandleScope scope(isolate);                      \
-    DCHECK(args.length() == 1);                      \
+    DCHECK_EQ(1, args.length());                     \
     CONVERT_ARG_HANDLE_CHECKED(JS##Type, holder, 0); \
     return holder->accessor();                       \
   }
 
 BUFFER_VIEW_GETTER(ArrayBufferView, ByteLength, byte_length)
 BUFFER_VIEW_GETTER(ArrayBufferView, ByteOffset, byte_offset)
 BUFFER_VIEW_GETTER(TypedArray, Length, length)
 BUFFER_VIEW_GETTER(DataView, Buffer, buffer)
 
 #undef BUFFER_VIEW_GETTER
 
 RUNTIME_FUNCTION(Runtime_TypedArrayGetBuffer) {
   HandleScope scope(isolate);
-  DCHECK(args.length() == 1);
+  DCHECK_EQ(1, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, holder, 0);
   return *holder->GetBuffer();
 }
 
 
 // Return codes for Runtime_TypedArraySetFastCases.
 // Should be synchronized with typedarray.js natives.
 enum TypedArraySetResultCodes {
   // Set from typed array of the same type.
   // This is processed by TypedArraySetFastCases
@@ skipping 19 matching lines @@
     return Smi::FromInt(TYPED_ARRAY_SET_NON_TYPED_ARRAY);
 
   CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, target_obj, 0);
   CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, source_obj, 1);
   CONVERT_NUMBER_ARG_HANDLE_CHECKED(offset_obj, 2);
 
   Handle<JSTypedArray> target(JSTypedArray::cast(*target_obj));
   Handle<JSTypedArray> source(JSTypedArray::cast(*source_obj));
   size_t offset = 0;
   RUNTIME_ASSERT(TryNumberToSize(isolate, *offset_obj, &offset));
-  size_t target_length = NumberToSize(isolate, target->length());
-  size_t source_length = NumberToSize(isolate, source->length());
+  size_t target_length = target->length_value();
+  size_t source_length = source->length_value();
   size_t target_byte_length = NumberToSize(isolate, target->byte_length());
   size_t source_byte_length = NumberToSize(isolate, source->byte_length());
   if (offset > target_length || offset + source_length > target_length ||
       offset + source_length < offset) {  // overflow
     THROW_NEW_ERROR_RETURN_FAILURE(
         isolate, NewRangeError(MessageTemplate::kTypedArraySetSourceTooLarge));
   }
 
   size_t target_offset = NumberToSize(isolate, target->byte_offset());
   size_t source_offset = NumberToSize(isolate, source->byte_offset());
@@ skipping 289 matching lines @@
 DATA_VIEW_SETTER(Uint16, uint16_t)
 DATA_VIEW_SETTER(Int16, int16_t)
 DATA_VIEW_SETTER(Uint32, uint32_t)
 DATA_VIEW_SETTER(Int32, int32_t)
 DATA_VIEW_SETTER(Float32, float)
 DATA_VIEW_SETTER(Float64, double)
 
 #undef DATA_VIEW_SETTER
 }  // namespace internal
 }  // namespace v8