Track field types.

src/property.h

Index: src/property.h
diff --git a/src/property.h b/src/property.h
index baa5a0f993c7e13be91b281e07d2d20659607eb2..53ce4539e566b35962aba6038f157fefe887a4bd 100644
--- a/src/property.h
+++ b/src/property.h
@@ -101,9 +101,12 @@ class FieldDescriptor: public Descriptor {
   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);
 };
 
 
@@ -205,11 +208,7 @@ class LookupResult BASE_EMBEDDED {
     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;
@@ -454,9 +453,13 @@ class LookupResult BASE_EMBEDDED {
   }
 
   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 {
@@ -465,6 +468,22 @@ class LookupResult BASE_EMBEDDED {
     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: