PropertyType is divided into PropertyKind and PropertyStoreMode.

src/property-details.h

Index: src/property-details.h
diff --git a/src/property-details.h b/src/property-details.h
index 4a3152d94d2e17e920f807614ae1ac054f047eba..dd29b1fa97580b731f91e4b1e07a15a3261cb7f2 100644
--- a/src/property-details.h
+++ b/src/property-details.h
@@ -41,10 +41,24 @@ typedef TypeImpl<ZoneTypeConfig> Type;
 class TypeInfo;
 
 // Type of properties.
+// Order of kinds is significant.
+// Must fit in the BitField PropertyDetails::KindField.
+enum PropertyKind { DATA = 0, ACCESSOR = 1 };
+
+
+// Order of modes is significant.
+// Must fit in the BitField PropertyDetails::StoreModeField.
+enum PropertyStoreMode { IN_OBJECT = 0, IN_DESCRIPTOR = 1 };

[Jakob Kummerow, 2014/12/12 12:19:04]

nit: we already have two enums called StoreMode. Can we call this one
PropertyStoreLocation?

[Igor Sheludko, 2014/12/12 12:38:30]

Renamed to PropertyLocation.

+
+
 // Order of properties is significant.
 // Must fit in the BitField PropertyDetails::TypeField.
 // A copy of this is in mirror-debugger.js.
-enum PropertyType { FIELD = 0, CONSTANT = 1, CALLBACKS = 2 };
+enum PropertyType {
+  FIELD = (IN_OBJECT << 1) | DATA,
+  CONSTANT = (IN_DESCRIPTOR << 1) | DATA,
+  CALLBACKS = (IN_DESCRIPTOR << 1) | ACCESSOR
+};
 
 
 class Representation {
@@ -222,6 +236,11 @@ class PropertyDetails BASE_EMBEDDED {
     return Representation::FromKind(static_cast<Representation::Kind>(bits));
   }
 
+  PropertyKind kind() const { return KindField::decode(value_); }
+  PropertyStoreMode store_mode() const {
+    return StoreModeField::decode(value_);
+  }
+
   PropertyType type() const { return TypeField::decode(value_); }
 
   PropertyAttributes attributes() const {
@@ -253,7 +272,8 @@ class PropertyDetails BASE_EMBEDDED {
 
   // Bit fields in value_ (type, shift, size). Must be public so the
   // constants can be embedded in generated code.
-  class TypeField : public BitField<PropertyType, 0, 2> {};
+  class KindField : public BitField<PropertyKind, 0, 1> {};
+  class StoreModeField : public BitField<PropertyStoreMode, 1, 1> {};
   class AttributesField : public BitField<PropertyAttributes, 2, 3> {};
 
   // Bit fields for normalized objects.
@@ -268,6 +288,12 @@ class PropertyDetails BASE_EMBEDDED {
       : public BitField<uint32_t, 9 + kDescriptorIndexBitCount,
                         kDescriptorIndexBitCount> {};  // NOLINT
 
+  // NOTE: TypeField overlaps with KindField and StoreModeField.
+  class TypeField : public BitField<PropertyType, 0, 2> {};
+  STATIC_ASSERT(KindField::kNext == StoreModeField::kShift);
+  STATIC_ASSERT(TypeField::kShift == KindField::kShift);
+  STATIC_ASSERT(TypeField::kNext == StoreModeField::kNext);
+
   // All bits for both fast and slow objects must fit in a smi.
   STATIC_ASSERT(DictionaryStorageField::kNext <= 31);
   STATIC_ASSERT(FieldIndexField::kNext <= 31);