heap/WriteBarrierBuffer.h

   1 /*
   2  * Copyright (C) 2013, 2015 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  23  * THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef WriteBarrierBuffer_h
  27 #define WriteBarrierBuffer_h
  28
  29 #include <wtf/FastMalloc.h>
  30
  31 namespace JSC {
  32
  33 class Heap;
  34 class JSCell;
  35
  36 class WriteBarrierBuffer {
  37 public:
  38     WriteBarrierBuffer(unsigned capacity);
  39     ~WriteBarrierBuffer();
  40
  41     void add(JSCell*);
  42     void flush(Heap&);
  43     void reset();
  44
  45     unsigned* currentIndexAddress()
  46     {
  47         return &m_currentIndex;
  48     }
  49
  50     unsigned capacity() const
  51     {
  52         return m_capacity;
  53     }
  54
  55     JSCell** buffer()
  56     {
  57         return m_buffer;
  58     }
  59
  60 private:
  61     unsigned m_currentIndex;
  62     const unsigned m_capacity;
  63     JSCell** const m_buffer;
  64 };
  65
  66 } // namespace JSC
  67
  68 #endif // WriteBarrierBuffer_h