PropertyType is divided into PropertyKind and PropertyStoreMode.

src/property-details.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_PROPERTY_DETAILS_H_
 #define V8_PROPERTY_DETAILS_H_
 
 #include "include/v8.h"
 #include "src/allocation.h"
 #include "src/utils.h"
@@ skipping 23 matching lines @@
 namespace v8 {
 namespace internal {
 
 class Smi;
 template<class> class TypeImpl;
 struct ZoneTypeConfig;
 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 {
  public:
   enum Kind {
     kNone,
     kInteger8,
     kUInteger8,
     kInteger16,
     kUInteger16,
@@ skipping 157 matching lines @@
   inline Smi* AsSmi() const;
 
   static uint8_t EncodeRepresentation(Representation representation) {
     return representation.kind();
   }
 
   static Representation DecodeRepresentation(uint32_t bits) {
     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 {
     return AttributesField::decode(value_);
   }
 
   int dictionary_index() const {
     return DictionaryStorageField::decode(value_);
   }
 
@@ skipping 11 matching lines @@
     return DictionaryStorageField::is_valid(index);
   }
 
   bool IsReadOnly() const { return (attributes() & READ_ONLY) != 0; }
   bool IsConfigurable() const { return (attributes() & DONT_DELETE) == 0; }
   bool IsDontEnum() const { return (attributes() & DONT_ENUM) != 0; }
   bool IsDeleted() const { return DeletedField::decode(value_) != 0; }
 
   // 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.
   class DeletedField : public BitField<uint32_t, 5, 1> {};
   class DictionaryStorageField : public BitField<uint32_t, 6, 24> {};
 
   // Bit fields for fast objects.
   class RepresentationField : public BitField<uint32_t, 5, 4> {};
   class DescriptorPointer
       : public BitField<uint32_t, 9, kDescriptorIndexBitCount> {};  // NOLINT
   class FieldIndexField
       : 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);
 
   static const int kInitialIndex = 1;
 
 #ifdef OBJECT_PRINT
   // For our gdb macros, we should perhaps change these in the future.
   void Print(bool dictionary_mode);
 #endif
@@ skipping 13 matching lines @@
   uint32_t value_;
 };
 
 
 std::ostream& operator<<(std::ostream& os,
                          const PropertyAttributes& attributes);
 std::ostream& operator<<(std::ostream& os, const PropertyDetails& details);
 } }  // namespace v8::internal
 
 #endif  // V8_PROPERTY_DETAILS_H_