Separating transitions from descriptors.

src/property-details.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 37 matching lines @@
 namespace v8 {
 namespace internal {
 
 class Smi;
 
 // Type of properties.
 // Order of properties is significant.
 // Must fit in the BitField PropertyDetails::TypeField.
 // A copy of this is in mirror-debugger.js.
 enum PropertyType {
-  NORMAL                    = 0,  // only in slow mode
-  FIELD                     = 1,  // only in fast mode
-  CONSTANT_FUNCTION         = 2,  // only in fast mode
+  // Only in slow mode.
+  NORMAL                    = 0,
+  // Only in fast mode.
+  FIELD                     = 1,
+  CONSTANT_FUNCTION         = 2,
   CALLBACKS                 = 3,
-  HANDLER                   = 4,  // only in lookup results, not in descriptors
-  INTERCEPTOR               = 5,  // only in lookup results, not in descriptors
-  // All properties before MAP_TRANSITION are real.
-  MAP_TRANSITION            = 6,  // only in fast mode
-  CONSTANT_TRANSITION       = 7,  // only in fast mode
+  // Only in lookup results, not in descriptors.
+  HANDLER                   = 4,
+  INTERCEPTOR               = 5,
+  TRANSITION                = 6,
   // Only used as a marker in LookupResult.
-  NONEXISTENT               = 8
+  NONEXISTENT               = 7
 };
 
 
 // PropertyDetails captures type and attributes for a property.
 // They are used both in property dictionaries and instance descriptors.
 class PropertyDetails BASE_EMBEDDED {
  public:
   PropertyDetails(PropertyAttributes attributes,
                   PropertyType type,
                   int index = 0) {
@@ skipping 26 matching lines @@
     return StorageField::is_valid(index);
   }
 
   bool IsReadOnly() { return (attributes() & READ_ONLY) != 0; }
   bool IsDontDelete() { return (attributes() & DONT_DELETE) != 0; }
   bool IsDontEnum() { return (attributes() & DONT_ENUM) != 0; }
   bool IsDeleted() { 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, 4> {};
-  class AttributesField: public BitField<PropertyAttributes, 4, 3> {};
-  class DeletedField:    public BitField<uint32_t,           7, 1> {};
-  class StorageField:    public BitField<uint32_t,           8, 32-8> {};
+  class TypeField:       public BitField<PropertyType,       0, 3> {};
+  class AttributesField: public BitField<PropertyAttributes, 3, 3> {};
+  class DeletedField:    public BitField<uint32_t,           6, 1> {};
+  class StorageField:    public BitField<uint32_t,           7, 32-7> {};
 
   static const int kInitialIndex = 1;
 
  private:
   uint32_t value_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROPERTY_DETAILS_H_