runtime/PropertyNameArray.cpp

   1 /*
   2  *  Copyright (C) 2006, 2008 Apple Inc. All rights reserved.
   3  *
   4  *  This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Library General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2 of the License, or (at your option) any later version.
   8  *
   9  *  This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Library General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU Library General Public License
  15  *  along with this library; see the file COPYING.LIB.  If not, write to
  16  *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  *  Boston, MA 02110-1301, USA.
  18  *
  19  */
  20
  21 #include "config.h"
  22 #include "PropertyNameArray.h"
  23
  24 #include "JSObject.h"
  25 #include "ScopeChain.h"
  26 #include "Structure.h"
  27 #include "StructureChain.h"
  28
  29 namespace JSC {
  30
  31 static const size_t setThreshold = 20;
  32
  33 void PropertyNameArray::add(StringImpl* identifier)
  34 {
  35     ASSERT(!identifier || identifier == StringImpl::empty() || identifier->isIdentifier());
  36
  37     size_t size = m_data->propertyNameVector().size();
  38     if (size < setThreshold) {
  39         for (size_t i = 0; i < size; ++i) {
  40             if (identifier == m_data->propertyNameVector()[i].impl())
  41                 return;
  42         }
  43     } else {
  44         if (m_set.isEmpty()) {
  45             for (size_t i = 0; i < size; ++i)
  46                 m_set.add(m_data->propertyNameVector()[i].impl());
  47         }
  48         if (!m_set.add(identifier).isNewEntry)
  49             return;
  50     }
  51
  52     addKnownUnique(identifier);
  53 }
  54
  55 } // namespace JSC