Revert "In-object double fields unboxing (for 64-bit only)."

src/heap/store-buffer.cc

Index: src/heap/store-buffer.cc
diff --git a/src/heap/store-buffer.cc b/src/heap/store-buffer.cc
index 4b94a95761774a05d3b44affed0b510caec4bbcd..278e9f2f6ee11a6835d93e6b942e26ab5e16b98d 100644
--- a/src/heap/store-buffer.cc
+++ b/src/heap/store-buffer.cc
@@ -507,33 +507,11 @@ void StoreBuffer::IteratePointersToNewSpace(ObjectSlotCallback slot_callback,
             for (HeapObject* heap_object = iterator.Next(); heap_object != NULL;
                  heap_object = iterator.Next()) {
               // We iterate over objects that contain new space pointers only.
-              bool may_contain_raw_values = heap_object->MayContainRawValues();
-              if (!may_contain_raw_values) {
-                Address obj_address = heap_object->address();
-                Address start_address = obj_address + HeapObject::kHeaderSize;
-                Address end_address = obj_address + heap_object->Size();
-#if V8_DOUBLE_FIELDS_UNBOXING
-                InobjectPropertiesHelper helper(heap_object->map());
-                bool has_only_tagged_fields = helper.all_fields_tagged();
-
-                if (!has_only_tagged_fields) {
-                  for (Address slot = start_address; slot < end_address;
-                       slot += kPointerSize) {
-                    if (helper.IsTagged(slot - obj_address)) {
-                      // TODO(ishell): call this once for contiguous region
-                      // of tagged fields.
-                      FindPointersToNewSpaceInRegion(slot, slot + kPointerSize,
-                                                     slot_callback, clear_maps);
-                    }
-                  }
-                } else {
-#endif
-                  // Object has only tagged fields.
-                  FindPointersToNewSpaceInRegion(start_address, end_address,
-                                                 slot_callback, clear_maps);
-#if V8_DOUBLE_FIELDS_UNBOXING
-                }
-#endif
+              if (!heap_object->MayContainRawValues()) {
+                FindPointersToNewSpaceInRegion(
+                    heap_object->address() + HeapObject::kHeaderSize,
+                    heap_object->address() + heap_object->Size(), slot_callback,
+                    clear_maps);
               }
             }
           }