Track field types.

src/property.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 83 matching lines @@
 
   friend class DescriptorArray;
 };
 
 
 class FieldDescriptor: public Descriptor {
  public:
   FieldDescriptor(Name* key,
                   int field_index,
                   PropertyAttributes attributes,
-                  Representation representation)
-      : Descriptor(key, Smi::FromInt(0), attributes,
-                   FIELD, representation, field_index) {}
+                  Representation representation);
+  FieldDescriptor(Name* key,
+                  int field_index,
+                  HeapType* field_type,
+                  PropertyAttributes attributes,
+                  Representation representation);
 };
 
 
 class ConstantDescriptor: public Descriptor {
  public:
   ConstantDescriptor(Name* key,
                      Object* value,
                      PropertyAttributes attributes)
       : Descriptor(key, value, attributes, CONSTANT,
                    value->OptimalRepresentation()) {}
@@ skipping 81 matching lines @@
   Isolate* isolate() const { return isolate_; }
 
   void DescriptorResult(JSObject* holder, PropertyDetails details, int number) {
     lookup_type_ = DESCRIPTOR_TYPE;
     holder_ = holder;
     transition_ = NULL;
     details_ = details;
     number_ = number;
   }
 
-  bool CanHoldValue(Handle<Object> value) {
-    if (IsNormal()) return true;
-    ASSERT(!IsTransition());
-    return value->FitsRepresentation(details_.representation());
-  }
+  bool CanHoldValue(Handle<Object> value) const;
 
   void TransitionResult(JSObject* holder, Map* target) {
     lookup_type_ = TRANSITION_TYPE;
     details_ = PropertyDetails(NONE, TRANSITION, Representation::None());
     holder_ = holder;
     transition_ = target;
     number_ = 0xAAAA;
   }
 
   void DictionaryResult(JSObject* holder, int entry) {
@@ skipping 224 matching lines @@
   Object* GetValue() const {
     if (lookup_type_ == DESCRIPTOR_TYPE) {
       return GetValueFromMap(holder()->map());
     }
     // In the dictionary case, the data is held in the value field.
     ASSERT(lookup_type_ == DICTIONARY_TYPE);
     return holder()->GetNormalizedProperty(this);
   }
 
   Object* GetValueFromMap(Map* map) const {
-    ASSERT(lookup_type_ == DESCRIPTOR_TYPE);
-    ASSERT(number_ < map->NumberOfOwnDescriptors());
-    return map->instance_descriptors()->GetValue(number_);
+    if (lookup_type_ == DESCRIPTOR_TYPE) {
+      ASSERT(number_ < map->NumberOfOwnDescriptors());
+      return map->instance_descriptors()->GetValue(number_);
+    }
+    ASSERT(lookup_type_ == TRANSITION_TYPE);
+    return transition_->instance_descriptors()->GetValue(
+        transition_->LastAdded());
   }
 
   int GetFieldIndexFromMap(Map* map) const {
     ASSERT(lookup_type_ == DESCRIPTOR_TYPE);
     ASSERT(number_ < map->NumberOfOwnDescriptors());
     return map->instance_descriptors()->GetFieldIndex(number_);
   }
 
+  HeapType* GetFieldType() const {
+    return GetFieldTypeFromMap(holder()->map());

[Toon Verwaest, 2014/03/21 14:33:37]

Aarg, this is ugly. We really need to cache holder()->map() rather than
holder(). Future CL I guess.

[Benedikt Meurer, 2014/04/11 11:12:00]

ACK.

+  }
+
+  HeapType* GetFieldTypeFromMap(Map* map) const;
+
+  Map* GetFieldOwner() const {
+    return GetFieldOwnerFromMap(holder()->map());
+  }
+
+  Map* GetFieldOwnerFromMap(Map* map) const {
+    ASSERT(lookup_type_ == DESCRIPTOR_TYPE);
+    ASSERT(number_ < map->NumberOfOwnDescriptors());
+    return map->FindFieldOwner(number_);
+  }
+
   void Iterate(ObjectVisitor* visitor);
 
  private:
   Isolate* isolate_;
   LookupResult* next_;
 
   // Where did we find the result;
   enum {
     NOT_FOUND,
     DESCRIPTOR_TYPE,
     TRANSITION_TYPE,
     DICTIONARY_TYPE,
     HANDLER_TYPE,
     INTERCEPTOR_TYPE
   } lookup_type_;
 
   JSReceiver* holder_;
   Map* transition_;
   int number_;
   bool cacheable_;
   PropertyDetails details_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROPERTY_H_