* Reapply revisions 1383, 1384, 1391, 1398, 1401, 1402,...

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 4870 matching lines @@
   } else {
     Object* obj = Heap::AllocateFixedArrayWithHoles(capacity);
     if (obj->IsFailure()) return obj;
     new_elements = FixedArray::cast(obj);
   }
   set_elements(new_elements);
   return this;
 }
 
 
+void JSArray::EnsureSize(int required_size) {
+  Handle<JSArray> self(this);
+  ASSERT(HasFastElements());
+  if (elements()->length() >= required_size) return;
+  Handle<FixedArray> old_backing(elements());
+  int old_size = old_backing->length();
+  // Doubling in size would be overkill, but leave some slack to avoid
+  // constantly growing.
+  int new_size = required_size + (required_size >> 3);
+  Handle<FixedArray> new_backing = Factory::NewFixedArray(new_size);
+  // Can't use this any more now because we may have had a GC!
+  for (int i = 0; i < old_size; i++) new_backing->set(i, old_backing->get(i));
+  self->SetContent(*new_backing);
+}
+
+
 // Computes the new capacity when expanding the elements of a JSObject.
 static int NewElementsCapacity(int old_capacity) {
   // (old_capacity + 50%) + 16
   return old_capacity + (old_capacity >> 1) + 16;
 }
 
 
 static Object* ArrayLengthRangeError() {
   HandleScope scope;
   return Top::Throw(*Factory::NewRangeError("invalid_array_length",
@@ skipping 2297 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