text: /*
   * Copyright (C) 2008 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1.  Redistributions of source code must retain the above copyright
   *     notice, this list of conditions and the following disclaimer.
   * 2.  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 with the distribution.
   * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
   *     its contributors may be used to endorse or promote products derived
   *     from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
   * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef RegisterID_h
  #define RegisterID_h
  
  #include <wtf/Assertions.h>
  #include <wtf/Noncopyable.h>
  #include <wtf/VectorTraits.h>
  
  namespace JSC {
  
      class RegisterID : public Noncopyable {
      public:
          RegisterID()
              : m_refCount(0)
              , m_isTemporary(false)
  #ifndef NDEBUG
              , m_didSetIndex(false)
  #endif
          {
          }
  
          explicit RegisterID(int index)
              : m_refCount(0)
              , m_index(index)
              , m_isTemporary(false)
  #ifndef NDEBUG
              , m_didSetIndex(true)
  #endif
          {
          }
  
          void setIndex(int index)
          {
              ASSERT(!m_refCount);
  #ifndef NDEBUG
              m_didSetIndex = true;
  #endif
              m_index = index;
          }
  
          void setTemporary()
          {
              m_isTemporary = true;
          }
  
          int index() const
          {
              ASSERT(m_didSetIndex);
              return m_index;
          }
  
          bool isTemporary()
          {
              return m_isTemporary;
          }
  
          void ref()
          {
              ++m_refCount;
          }
  
          void deref()
          {
              --m_refCount;
              ASSERT(m_refCount >= 0);
          }
  
          int refCount() const
          {
              return m_refCount;
          }
  
      private:
  
          int m_refCount;
          int m_index;
          bool m_isTemporary;
  #ifndef NDEBUG
          bool m_didSetIndex;
  #endif
      };
  
  } // namespace JSC
  
  namespace WTF {
  
      template<> struct VectorTraits<JSC::RegisterID> : VectorTraitsBase<true, JSC::RegisterID> {
          static const bool needsInitialization = true;
          static const bool canInitializeWithMemset = true; // Default initialization just sets everything to 0 or false, so this is safe.
      };
  
  } // namespace WTF
  
  #endif // RegisterID_h
  