Avoid manual object's body traversal in GC.

src/heap/objects-visiting-inl.h

Index: src/heap/objects-visiting-inl.h
diff --git a/src/heap/objects-visiting-inl.h b/src/heap/objects-visiting-inl.h
index d6a189a98d20f75a1008dcae492d6f2921411984..d109a8fa82990431457bf1b228c94874abcade1b 100644
--- a/src/heap/objects-visiting-inl.h
+++ b/src/heap/objects-visiting-inl.h
@@ -94,14 +94,14 @@ void StaticNewSpaceVisitor<StaticVisitor>::Initialize() {
 template <typename StaticVisitor>
 int StaticNewSpaceVisitor<StaticVisitor>::VisitJSArrayBuffer(
     Map* map, HeapObject* object) {
-  Heap* heap = map->GetHeap();
+  typedef FlexibleBodyVisitor<StaticVisitor, JSArrayBuffer::BodyDescriptor, int>
+      JSArrayBufferBodyVisitor;
 
-  JSArrayBuffer::JSArrayBufferIterateBody<
-      StaticNewSpaceVisitor<StaticVisitor> >(heap, object);
   if (!JSArrayBuffer::cast(object)->is_external()) {
+    Heap* heap = map->GetHeap();
     heap->array_buffer_tracker()->MarkLive(JSArrayBuffer::cast(object));
   }
-  return JSArrayBuffer::kSizeWithInternalFields;
+  return JSArrayBufferBodyVisitor::Visit(map, object);
 }
 
 
@@ -525,12 +525,9 @@ void StaticMarkingVisitor<StaticVisitor>::VisitJSFunction(Map* map,
 template <typename StaticVisitor>
 void StaticMarkingVisitor<StaticVisitor>::VisitJSRegExp(Map* map,
                                                         HeapObject* object) {
-  int last_property_offset =
-      JSRegExp::kSize + kPointerSize * map->GetInObjectProperties();
-  StaticVisitor::VisitPointers(
-      map->GetHeap(), object,
-      HeapObject::RawField(object, JSRegExp::kPropertiesOffset),
-      HeapObject::RawField(object, last_property_offset));
+  typedef FlexibleBodyVisitor<StaticVisitor, JSRegExp::BodyDescriptor, void>
+      JSRegExpBodyVisitor;
+  JSRegExpBodyVisitor::Visit(map, object);
 }
 
 
@@ -539,7 +536,11 @@ void StaticMarkingVisitor<StaticVisitor>::VisitJSArrayBuffer(
     Map* map, HeapObject* object) {
   Heap* heap = map->GetHeap();
 
-  JSArrayBuffer::JSArrayBufferIterateBody<StaticVisitor>(heap, object);
+  typedef FlexibleBodyVisitor<StaticVisitor, JSArrayBuffer::BodyDescriptor,
+                              void> JSArrayBufferBodyVisitor;
+
+  JSArrayBufferBodyVisitor::Visit(map, object);
+
   if (!JSArrayBuffer::cast(object)->is_external() &&
       !heap->InNewSpace(object)) {
     heap->array_buffer_tracker()->MarkLive(JSArrayBuffer::cast(object));
@@ -550,20 +551,18 @@ void StaticMarkingVisitor<StaticVisitor>::VisitJSArrayBuffer(
 template <typename StaticVisitor>
 void StaticMarkingVisitor<StaticVisitor>::VisitJSTypedArray(
     Map* map, HeapObject* object) {
-  StaticVisitor::VisitPointers(
-      map->GetHeap(), object,
-      HeapObject::RawField(object, JSTypedArray::BodyDescriptor::kStartOffset),
-      HeapObject::RawField(object, JSTypedArray::kSizeWithInternalFields));
+  typedef FlexibleBodyVisitor<StaticVisitor, JSTypedArray::BodyDescriptor, void>
+      JSTypedArrayBodyVisitor;
+  JSTypedArrayBodyVisitor::Visit(map, object);
 }
 
 
 template <typename StaticVisitor>
 void StaticMarkingVisitor<StaticVisitor>::VisitJSDataView(Map* map,
                                                           HeapObject* object) {
-  StaticVisitor::VisitPointers(
-      map->GetHeap(), object,
-      HeapObject::RawField(object, JSDataView::BodyDescriptor::kStartOffset),
-      HeapObject::RawField(object, JSDataView::kSizeWithInternalFields));
+  typedef FlexibleBodyVisitor<StaticVisitor, JSDataView::BodyDescriptor, void>
+      JSDataViewBodyVisitor;
+  JSDataViewBodyVisitor::Visit(map, object);
 }