// static
-MaybeHandle<Map> Map::CurrentMapForDeprecatedInternal(Handle<Map> map) {
- if (!map->is_deprecated()) return map;
-
+MaybeHandle<Map> Map::CurrentMapForDeprecatedInternal(Handle<Map> old_map) {
DisallowHeapAllocation no_allocation;
- DescriptorArray* old_descriptors = map->instance_descriptors();
- int descriptors = map->NumberOfOwnDescriptors();
- Map* root_map = map->FindRootMap();
+ if (!old_map->is_deprecated()) return old_map;
// Check the state of the root map.
- if (!map->EquivalentToForTransition(root_map)) return MaybeHandle<Map>();
- int verbatim = root_map->NumberOfOwnDescriptors();
+ Map* root_map = old_map->FindRootMap();
+ if (!old_map->EquivalentToForTransition(root_map)) return MaybeHandle<Map>();
+ int root_nof = root_map->NumberOfOwnDescriptors();
- Map* updated = root_map->FindUpdatedMap(
- verbatim, descriptors, old_descriptors);
- if (updated == NULL) return MaybeHandle<Map>();
+ int old_nof = old_map->NumberOfOwnDescriptors();
+ DescriptorArray* old_descriptors = old_map->instance_descriptors();
- DescriptorArray* updated_descriptors = updated->instance_descriptors();
- int valid = updated->NumberOfOwnDescriptors();
- if (!updated_descriptors->IsMoreGeneralThan(
- verbatim, valid, descriptors, old_descriptors)) {
- return MaybeHandle<Map>();
- }
+ Map* new_map = root_map;
+ for (int i = root_nof; i < old_nof; ++i) {
+ int j = new_map->SearchTransition(old_descriptors->GetKey(i));
+ if (j == TransitionArray::kNotFound) return MaybeHandle<Map>();
+ new_map = new_map->GetTransition(j);
+ DescriptorArray* new_descriptors = new_map->instance_descriptors();
- return handle(updated);
+ PropertyDetails new_details = new_descriptors->GetDetails(i);
+ PropertyDetails old_details = old_descriptors->GetDetails(i);
+ if (old_details.attributes() != new_details.attributes() ||
+ !old_details.representation().fits_into(new_details.representation())) {
+ return MaybeHandle<Map>();
+ }
+ PropertyType new_type = new_details.type();
+ PropertyType old_type = old_details.type();
+ Object* new_value = new_descriptors->GetValue(i);
+ Object* old_value = old_descriptors->GetValue(i);
+ switch (new_type) {
+ case FIELD:
+ if ((old_type == FIELD &&
+ !HeapType::cast(old_value)->NowIs(HeapType::cast(new_value))) ||
+ (old_type == CONSTANT &&
+ !HeapType::cast(new_value)->NowContains(old_value)) ||
+ (old_type == CALLBACKS &&
+ !HeapType::Any()->Is(HeapType::cast(new_value)))) {
+ return MaybeHandle<Map>();
+ }
+ break;
+
+ case CONSTANT:
+ case CALLBACKS:
+ if (old_type != new_type || old_value != new_value) {
+ return MaybeHandle<Map>();
+ }
+ break;
+
+ case NORMAL:
+ case HANDLER:
+ case INTERCEPTOR:
+ case NONEXISTENT:
+ UNREACHABLE();
+ }
+ }
+ if (new_map->NumberOfOwnDescriptors() != old_nof) return MaybeHandle<Map>();
+ return handle(new_map);
}