Store weak cell cache for map in the map itself.

src/heap/heap.cc

 // Copyright 2012 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/accessors.h"
 #include "src/api.h"
 #include "src/base/bits.h"
 #include "src/base/once.h"
@@ skipping 2431 matching lines @@
   }
   reinterpret_cast<Map*>(result)->set_inobject_properties(0);
   reinterpret_cast<Map*>(result)->set_pre_allocated_property_fields(0);
   reinterpret_cast<Map*>(result)->set_unused_property_fields(0);
   reinterpret_cast<Map*>(result)->set_bit_field(0);
   reinterpret_cast<Map*>(result)->set_bit_field2(0);
   int bit_field3 = Map::EnumLengthBits::encode(kInvalidEnumCacheSentinel) |
                    Map::OwnsDescriptors::encode(true) |
                    Map::Counter::encode(Map::kRetainingCounterStart);
   reinterpret_cast<Map*>(result)->set_bit_field3(bit_field3);
+  reinterpret_cast<Map*>(result)->set_weak_cell_cache(Smi::FromInt(0));
   return result;
 }
 
 
 AllocationResult Heap::AllocateMap(InstanceType instance_type,
                                    int instance_size,
                                    ElementsKind elements_kind) {
   HeapObject* result;
   AllocationResult allocation = AllocateRaw(Map::kSize, MAP_SPACE, MAP_SPACE);
   if (!allocation.To(&result)) return allocation;
 
   result->set_map_no_write_barrier(meta_map());
   Map* map = Map::cast(result);
   map->set_instance_type(instance_type);
   map->set_prototype(null_value(), SKIP_WRITE_BARRIER);
   map->set_constructor_or_backpointer(null_value(), SKIP_WRITE_BARRIER);
   map->set_instance_size(instance_size);
   map->set_inobject_properties(0);
   map->set_pre_allocated_property_fields(0);
   map->set_code_cache(empty_fixed_array(), SKIP_WRITE_BARRIER);
   map->set_dependent_code(DependentCode::cast(empty_fixed_array()),
                           SKIP_WRITE_BARRIER);
+  map->set_weak_cell_cache(Smi::FromInt(0));
   map->init_transitions(undefined_value());
   map->set_unused_property_fields(0);
   map->set_instance_descriptors(empty_descriptor_array());
   if (FLAG_unbox_double_fields) {
     map->set_layout_descriptor(LayoutDescriptor::FastPointerLayout());
   }
   // Must be called only after |instance_type|, |instance_size| and
   // |layout_descriptor| are set.
   map->set_visitor_id(StaticVisitorBase::GetVisitorId(map));
   map->set_bit_field(0);
@@ skipping 4038 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 }
 }  // namespace v8::internal