DescriptorArray::IsProperty-related cleanup.

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 3755 matching lines @@
 
 MaybeObject* JSObject::GetHiddenPropertiesDictionary(bool create_if_absent) {
   ASSERT(!IsJSGlobalProxy());
   if (HasFastProperties()) {
     // If the object has fast properties, check whether the first slot
     // in the descriptor array matches the hidden symbol. Since the
     // hidden symbols hash code is zero (and no other string has hash
     // code zero) it will always occupy the first entry if present.
     DescriptorArray* descriptors = this->map()->instance_descriptors();
     if ((descriptors->number_of_descriptors() > 0) &&
-        (descriptors->GetKey(0) == GetHeap()->hidden_symbol()) &&
-        descriptors->IsProperty(0)) {
-      ASSERT(descriptors->GetType(0) == FIELD);
-      Object* hidden_store =
-          this->FastPropertyAt(descriptors->GetFieldIndex(0));
-      return StringDictionary::cast(hidden_store);
+        (descriptors->GetKey(0) == GetHeap()->hidden_symbol())) {
+      if (descriptors->GetType(0) == FIELD) {
+        Object* hidden_store =
+            this->FastPropertyAt(descriptors->GetFieldIndex(0));
+        return StringDictionary::cast(hidden_store);
+      } else {
+        ASSERT(descriptors->GetType(0) == MAP_TRANSITION);
+      }
     }
   } else {
     PropertyAttributes attributes;
     // You can't install a getter on a property indexed by the hidden symbol,
     // so we can be sure that GetLocalPropertyPostInterceptor returns a real
     // object.
     Object* lookup =
         GetLocalPropertyPostInterceptor(this,
                                         GetHeap()->hidden_symbol(),
                                         &attributes)->ToObjectUnchecked();
@@ skipping 20 matching lines @@
     StringDictionary* dictionary) {
   ASSERT(!IsJSGlobalProxy());
   ASSERT(HasHiddenProperties());
   if (HasFastProperties()) {
     // If the object has fast properties, check whether the first slot
     // in the descriptor array matches the hidden symbol. Since the
     // hidden symbols hash code is zero (and no other string has hash
     // code zero) it will always occupy the first entry if present.
     DescriptorArray* descriptors = this->map()->instance_descriptors();
     if ((descriptors->number_of_descriptors() > 0) &&
-        (descriptors->GetKey(0) == GetHeap()->hidden_symbol()) &&
-        descriptors->IsProperty(0)) {
-      ASSERT(descriptors->GetType(0) == FIELD);
-      this->FastPropertyAtPut(descriptors->GetFieldIndex(0), dictionary);
-      return this;
+        (descriptors->GetKey(0) == GetHeap()->hidden_symbol())) {
+      if (descriptors->GetType(0) == FIELD) {
+        this->FastPropertyAtPut(descriptors->GetFieldIndex(0), dictionary);
+        return this;
+      } else {
+        ASSERT(descriptors->GetType(0) == MAP_TRANSITION);
+      }
     }
   }
   MaybeObject* store_result =
       SetPropertyPostInterceptor(GetHeap()->hidden_symbol(),
                                  dictionary,
                                  DONT_ENUM,
                                  kNonStrictMode);
   if (store_result->IsFailure()) return store_result;
   return this;
 }
@@ skipping 1988 matching lines @@
   return new_descriptors;
 }
 
 
 MaybeObject* DescriptorArray::RemoveTransitions() {
   // Remove all transitions and null descriptors. Return a copy of the array
   // with all transitions removed, or a Failure object if the new array could
   // not be allocated.
 
   // Compute the size of the map transition entries to be removed.
-  int num_removed = 0;
+  int new_number_of_descriptors = 0;
   for (int i = 0; i < number_of_descriptors(); i++) {
-    if (!IsProperty(i)) num_removed++;
+    if (IsProperty(i)) new_number_of_descriptors++;
   }
 
   // Allocate the new descriptor array.
   DescriptorArray* new_descriptors;
-  { MaybeObject* maybe_result = Allocate(number_of_descriptors() - num_removed);
+  { MaybeObject* maybe_result = Allocate(new_number_of_descriptors);
     if (!maybe_result->To<DescriptorArray>(&new_descriptors)) {
       return maybe_result;
     }
   }
 
   DescriptorArray::WhitenessWitness witness(new_descriptors);
 
   // Copy the content.
   int next_descriptor = 0;
   for (int i = 0; i < number_of_descriptors(); i++) {
@@ skipping 7174 matching lines @@
   if (break_point_objects()->IsUndefined()) return 0;
   // Single break point.
   if (!break_point_objects()->IsFixedArray()) return 1;
   // Multiple break points.
   return FixedArray::cast(break_point_objects())->length();
 }
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 
 } }  // namespace v8::internal