Store offset between fixed typed array base and data start in object

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index 3340a0fd384a3cdf8bb9e11a90b00f9f00b3b249..a799eb524a347de49c36ef83e47e6aea27855468 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -4007,6 +4007,10 @@ AllocationResult Heap::AllocateFixedTypedArray(int length,
   object->set_map(MapForFixedTypedArray(array_type));
   FixedTypedArrayBase* elements = FixedTypedArrayBase::cast(object);
   elements->set_base_pointer(elements, SKIP_WRITE_BARRIER);
+  elements->set_external_pointer(
+      reinterpret_cast<void*>(FixedTypedArrayBase::kDataOffset -
+                              kHeapObjectTag),

[Jarin, 2015/07/22 09:00:20]

Can't you say ExternalReference::fixed_typed_array_base_data_offset().address()
here?

[jochen (gone - plz use gerrit), 2015/07/22 09:08:13]

done

+      SKIP_WRITE_BARRIER);
   elements->set_length(length);
   if (initialize) memset(elements->DataPtr(), 0, elements->DataSize());
   return elements;