bytecompiler/RegisterID.h

   1 /*
   2  * Copyright (C) 2008 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  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
  14  *     its contributors may be used to endorse or promote products derived
  15  *     from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #ifndef RegisterID_h
  30 #define RegisterID_h
  31
  32 #include "VirtualRegister.h"
  33
  34 #include <wtf/Assertions.h>
  35 #include <wtf/VectorTraits.h>
  36
  37 namespace JSC {
  38
  39     class RegisterID {
  40         WTF_MAKE_NONCOPYABLE(RegisterID);
  41     public:
  42         RegisterID()
  43             : m_refCount(0)
  44             , m_isTemporary(false)
  45 #ifndef NDEBUG
  46             , m_didSetIndex(false)
  47 #endif
  48         {
  49         }
  50
  51         RegisterID(VirtualRegister virtualRegister)
  52             : m_refCount(0)
  53             , m_virtualRegister(virtualRegister)
  54             , m_isTemporary(false)
  55 #ifndef NDEBUG
  56             , m_didSetIndex(true)
  57 #endif
  58         {
  59         }
  60
  61         explicit RegisterID(int index)
  62             : m_refCount(0)
  63             , m_virtualRegister(VirtualRegister(index))
  64             , m_isTemporary(false)
  65 #ifndef NDEBUG
  66             , m_didSetIndex(true)
  67 #endif
  68         {
  69         }
  70
  71         void setIndex(int index)
  72         {
  73             ASSERT(!m_refCount);
  74 #ifndef NDEBUG
  75             m_didSetIndex = true;
  76 #endif
  77             m_virtualRegister = VirtualRegister(index);
  78         }
  79
  80         void setTemporary()
  81         {
  82             m_isTemporary = true;
  83         }
  84
  85         int index() const
  86         {
  87             ASSERT(m_didSetIndex);
  88             return m_virtualRegister.offset();
  89         }
  90
  91         VirtualRegister virtualRegister() const
  92         {
  93             ASSERT(m_virtualRegister.isValid());
  94             return m_virtualRegister;
  95         }
  96
  97         bool isTemporary()
  98         {
  99             return m_isTemporary;
 100         }
 101
 102         void ref()
 103         {
 104             ++m_refCount;
 105         }
 106
 107         void deref()
 108         {
 109             --m_refCount;
 110             ASSERT(m_refCount >= 0);
 111         }
 112
 113         int refCount() const
 114         {
 115             return m_refCount;
 116         }
 117
 118     private:
 119
 120         int m_refCount;
 121         VirtualRegister m_virtualRegister;
 122         bool m_isTemporary;
 123 #ifndef NDEBUG
 124         bool m_didSetIndex;
 125 #endif
 126     };
 127
 128 } // namespace JSC
 129
 130 namespace WTF {
 131
 132     template<> struct VectorTraits<JSC::RegisterID> : VectorTraitsBase<true, JSC::RegisterID> {
 133         static const bool needsInitialization = true;
 134         static const bool canInitializeWithMemset = true; // Default initialization just sets everything to 0 or false, so this is safe.
 135     };
 136
 137 } // namespace WTF
 138
 139 #endif // RegisterID_h