- Optimized copying of FixedArray.

src/objects.cc

 // Copyright 2006-2008 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 871 matching lines @@
   // print that using vsnprintf (which may truncate but never allocate if
   // there is no more space in the buffer).
   EmbeddedVector<char, 100> buffer;
   OS::SNPrintF(buffer, "%.16g", Number());
   accumulator->Add("%s", buffer.start());
 }
 
 
 String* JSObject::class_name() {
   if (IsJSFunction()) return Heap::function_class_symbol();
-  // If the constructor is not present "Object" is returned.
-  String* result = Heap::Object_symbol();
   if (map()->constructor()->IsJSFunction()) {
     JSFunction* constructor = JSFunction::cast(map()->constructor());
     return String::cast(constructor->shared()->instance_class_name());
   }
-  return result;
+  // If the constructor is not present, return "Object".
+  return Heap::Object_symbol();
 }
 
 
 void JSObject::JSObjectIterateBody(int object_size, ObjectVisitor* v) {
   // Iterate over all fields in the body. Assumes all are Object*.
   IteratePointers(v, kPropertiesOffset, object_size);
 }
 
 
 Object* JSObject::Copy(PretenureFlag pretenure) {
@@ skipping 1622 matching lines @@
     if (!HasKey(this, other->get(y))) {
       result->set(len0 + index, other->get(y));
       index++;
     }
   }
   ASSERT(extra == index);
   return result;
 }
 
 
-Object* FixedArray::Copy() {
-  int len = length();
-  if (len == 0) return this;
-  Object* obj = Heap::AllocateFixedArray(len);
-  if (obj->IsFailure()) return obj;
-  FixedArray* result = FixedArray::cast(obj);
-  WriteBarrierMode mode = result->GetWriteBarrierMode();
-  // Copy the content
-  for (int i = 0; i < len; i++) {
-    result->set(i, get(i), mode);
-  }
-  result->set_map(map());
-  return result;
-}
-
 Object* FixedArray::CopySize(int new_length) {
   if (new_length == 0) return Heap::empty_fixed_array();
   Object* obj = Heap::AllocateFixedArray(new_length);
   if (obj->IsFailure()) return obj;
   FixedArray* result = FixedArray::cast(obj);
   WriteBarrierMode mode = result->GetWriteBarrierMode();
   // Copy the content
   int len = length();
   if (new_length < len) len = new_length;
   for (int i = 0; i < len; i++) {
@@ skipping 3858 matching lines @@
   // No break point.
   if (break_point_objects()->IsUndefined()) return 0;
   // Single beak point.
   if (!break_point_objects()->IsFixedArray()) return 1;
   // Multiple break points.
   return FixedArray::cast(break_point_objects())->length();
 }
 
 
 } }  // namespace v8::internal