Always fix up the enumeration indices when turning to fast mode.

src/objects.cc

 // 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 12456 matching lines @@
   return heap->undefined_value();
 }
 
 
 MaybeObject* StringDictionary::TransformPropertiesToFastFor(
     JSObject* obj, int unused_property_fields) {
   // Make sure we preserve dictionary representation if there are too many
   // descriptors.
   if (NumberOfElements() > DescriptorArray::kMaxNumberOfDescriptors) return obj;
 
-  // Figure out if it is necessary to generate new enumeration indices.
-  int max_enumeration_index =
-      NextEnumerationIndex() +

[danno, 2012/07/17 09:55:02]

nit: put this on previous line, adjust spacing below as appropriate.

-          (DescriptorArray::kMaxNumberOfDescriptors -
-           NumberOfElements());
-  if (!PropertyDetails::IsValidIndex(max_enumeration_index)) {
-    Object* result;
-    { MaybeObject* maybe_result = GenerateNewEnumerationIndices();
-      if (!maybe_result->ToObject(&result)) return maybe_result;
-    }
-  }
+  MaybeObject* maybe_result = GenerateNewEnumerationIndices();
+  if (maybe_result->IsFailure()) return maybe_result;
 
   int instance_descriptor_length = 0;
   int number_of_fields = 0;
 
   Heap* heap = GetHeap();
 
   // Compute the length of the instance descriptor.
   int capacity = Capacity();
   for (int i = 0; i < capacity; i++) {
     Object* k = KeyAt(i);
     if (IsKey(k)) {
       Object* value = ValueAt(i);
       PropertyType type = DetailsAt(i).type();
       ASSERT(type != FIELD);
       instance_descriptor_length++;
       if (type == NORMAL &&
           (!value->IsJSFunction() || heap->InNewSpace(value))) {
         number_of_fields += 1;
       }
     }
   }
 
   // Allocate the instance descriptor.
   DescriptorArray* descriptors;
-  { MaybeObject* maybe_descriptors =
-        DescriptorArray::Allocate(instance_descriptor_length,
-                                  DescriptorArray::MAY_BE_SHARED);
-    if (!maybe_descriptors->To<DescriptorArray>(&descriptors)) {
-      return maybe_descriptors;
-    }
+  MaybeObject* maybe_descriptors =
+      DescriptorArray::Allocate(instance_descriptor_length,
+                                DescriptorArray::MAY_BE_SHARED);
+  if (!maybe_descriptors->To(&descriptors)) {
+    return maybe_descriptors;
   }
 
   FixedArray::WhitenessWitness witness(descriptors);
 
   int inobject_props = obj->map()->inobject_properties();
   int number_of_allocated_fields =
       number_of_fields + unused_property_fields - inobject_props;
   if (number_of_allocated_fields < 0) {
     // There is enough inobject space for all fields (including unused).
     number_of_allocated_fields = 0;
     unused_property_fields = inobject_props - number_of_fields;
   }
 
   // Allocate the fixed array for the fields.
-  Object* fields;
+  FixedArray* fields;
   MaybeObject* maybe_fields =
       heap->AllocateFixedArray(number_of_allocated_fields);
-  if (!maybe_fields->ToObject(&fields)) return maybe_fields;
+  if (!maybe_fields->To(&fields)) return maybe_fields;
 
   // Fill in the instance descriptor and the fields.
   int next_descriptor = 0;
   int current_offset = 0;
   for (int i = 0; i < capacity; i++) {
     Object* k = KeyAt(i);
     if (IsKey(k)) {
       Object* value = ValueAt(i);
       // Ensure the key is a symbol before writing into the instance descriptor.
       String* key;
       MaybeObject* maybe_key = heap->LookupSymbol(String::cast(k));
       if (!maybe_key->To(&key)) return maybe_key;
 
       PropertyDetails details = DetailsAt(i);
       PropertyType type = details.type();
 
       if (value->IsJSFunction() && !heap->InNewSpace(value)) {
         ConstantFunctionDescriptor d(key,
                                      JSFunction::cast(value),
                                      details.attributes(),
                                      details.index());
         descriptors->Set(next_descriptor, &d, witness);
       } else if (type == NORMAL) {
         if (current_offset < inobject_props) {
           obj->InObjectPropertyAtPut(current_offset,
                                      value,
                                      UPDATE_WRITE_BARRIER);
         } else {
           int offset = current_offset - inobject_props;
-          FixedArray::cast(fields)->set(offset, value);
+          fields->set(offset, value);
         }
         FieldDescriptor d(key,
                           current_offset++,
                           details.attributes(),
                           details.index());
         descriptors->Set(next_descriptor, &d, witness);
       } else if (type == CALLBACKS) {
         CallbacksDescriptor d(key,
                               value,
                               details.attributes(),
@@ skipping 11 matching lines @@
   // Allocate new map.
   Map* new_map;
   MaybeObject* maybe_new_map = obj->map()->CopyReplaceDescriptors(descriptors);
   if (!maybe_new_map->To(&new_map)) return maybe_new_map;
 
   new_map->set_unused_property_fields(unused_property_fields);
 
   // Transform the object.
   obj->set_map(new_map);
 
-  obj->set_properties(FixedArray::cast(fields));
+  obj->set_properties(fields);
   ASSERT(obj->IsJSObject());
 
   // Check that it really works.
   ASSERT(obj->HasFastProperties());
 
   return obj;
 }
 
 
 bool ObjectHashSet::Contains(Object* key) {
@@ skipping 493 matching lines @@
   set_year(Smi::FromInt(year), SKIP_WRITE_BARRIER);
   set_month(Smi::FromInt(month), SKIP_WRITE_BARRIER);
   set_day(Smi::FromInt(day), SKIP_WRITE_BARRIER);
   set_weekday(Smi::FromInt(weekday), SKIP_WRITE_BARRIER);
   set_hour(Smi::FromInt(hour), SKIP_WRITE_BARRIER);
   set_min(Smi::FromInt(min), SKIP_WRITE_BARRIER);
   set_sec(Smi::FromInt(sec), SKIP_WRITE_BARRIER);
 }
 
 } }  // namespace v8::internal