TransitionArray now uses <is_data_property, name, attributes> tuple as a key, which allows to have …

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 6d0f8d4e61110b55e641ad0b02dcf5dab36e2853..ebc95b7cac016f2e496967ad6960b9f633c0582d 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -1884,11 +1884,10 @@ Handle<Map> Map::FindTransitionToField(Handle<Map> map, Handle<Name> key) {
   DisallowHeapAllocation no_allocation;
   if (!map->HasTransitionArray()) return Handle<Map>::null();
   TransitionArray* transitions = map->transitions();
-  int transition = transitions->Search(*key);
+  int transition = transitions->Search(FIELD, *key, NONE);
   if (transition == TransitionArray::kNotFound) return Handle<Map>::null();
-  PropertyDetails target_details = transitions->GetTargetDetails(transition);
-  if (target_details.type() != FIELD) return Handle<Map>::null();
-  if (target_details.attributes() != NONE) return Handle<Map>::null();
+  DCHECK_EQ(FIELD, transitions->GetTargetDetails(transition).type());
+  DCHECK_EQ(NONE, transitions->GetTargetDetails(transition).attributes());
   return Handle<Map>(transitions->GetTarget(transition));
 }
 
@@ -2943,10 +2942,10 @@ void Map::LookupDescriptor(JSObject* holder,
 }
 
 
-void Map::LookupTransition(JSObject* holder,
-                           Name* name,
+void Map::LookupTransition(JSObject* holder, Name* name,
+                           PropertyAttributes attributes,
                            LookupResult* result) {
-  int transition_index = this->SearchTransition(name);
+  int transition_index = this->SearchTransition(FIELD, name, attributes);
   if (transition_index == TransitionArray::kNotFound) return result->NotFound();
   result->TransitionResult(holder, this->GetTransition(transition_index));
 }
@@ -5217,7 +5216,8 @@ bool Map::HasTransitionArray() const {
 
 
 Map* Map::elements_transition_map() {
-  int index = transitions()->Search(GetHeap()->elements_transition_symbol());
+  int index =
+      transitions()->SearchSpecial(GetHeap()->elements_transition_symbol());
   return transitions()->GetTarget(index);
 }
 
@@ -5234,8 +5234,19 @@ Map* Map::GetTransition(int transition_index) {
 }
 
 
-int Map::SearchTransition(Name* name) {
-  if (HasTransitionArray()) return transitions()->Search(name);
+int Map::SearchSpecialTransition(Symbol* name) {
+  if (HasTransitionArray()) {
+    return transitions()->SearchSpecial(name);
+  }
+  return TransitionArray::kNotFound;
+}
+
+
+int Map::SearchTransition(PropertyType type, Name* name,
+                          PropertyAttributes attributes) {
+  if (HasTransitionArray()) {
+    return transitions()->Search(type, name, attributes);
+  }
   return TransitionArray::kNotFound;
 }
 
@@ -5288,9 +5299,17 @@ void Map::set_transitions(TransitionArray* transition_array,
       Map* target = transitions()->GetTarget(i);
       if (target->instance_descriptors() == instance_descriptors()) {
         Name* key = transitions()->GetKey(i);
-        int new_target_index = transition_array->Search(key);
-        DCHECK(new_target_index != TransitionArray::kNotFound);
-        DCHECK(transition_array->GetTarget(new_target_index) == target);
+        int new_target_index;
+        if (TransitionArray::IsSpecialTransition(key)) {
+          new_target_index = transition_array->SearchSpecial(Symbol::cast(key));
+        } else {
+          PropertyDetails details =
+              TransitionArray::GetTargetDetails(key, target);
+          new_target_index = transition_array->Search(details.type(), key,
+                                                      details.attributes());
+        }
+        DCHECK_NE(TransitionArray::kNotFound, new_target_index);
+        DCHECK_EQ(target, transition_array->GetTarget(new_target_index));
       }
     }
 #endif