bytecode/PutByIdVariant.h

   1 /*
   2  * Copyright (C) 2014 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. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef PutByIdVariant_h
  27 #define PutByIdVariant_h
  28
  29 #include "IntendedStructureChain.h"
  30 #include "PropertyOffset.h"
  31
  32 namespace JSC {
  33
  34 class PutByIdVariant {
  35 public:
  36     enum Kind {
  37         NotSet,
  38         Replace,
  39         Transition
  40     };
  41
  42     PutByIdVariant()
  43         : m_kind(NotSet)
  44         , m_oldStructure(0)
  45         , m_newStructure(0)
  46         , m_offset(invalidOffset)
  47     {
  48     }
  49
  50     static PutByIdVariant replace(Structure* structure, PropertyOffset offset)
  51     {
  52         PutByIdVariant result;
  53         result.m_kind = Replace;
  54         result.m_oldStructure = structure;
  55         result.m_offset = offset;
  56         return result;
  57     }
  58
  59     static PutByIdVariant transition(
  60         Structure* oldStructure, Structure* newStructure,
  61         PassRefPtr<IntendedStructureChain> structureChain, PropertyOffset offset)
  62     {
  63         PutByIdVariant result;
  64         result.m_kind = Transition;
  65         result.m_oldStructure = oldStructure;
  66         result.m_newStructure = newStructure;
  67         result.m_structureChain = structureChain;
  68         result.m_offset = offset;
  69         return result;
  70     }
  71
  72     Kind kind() const { return m_kind; }
  73
  74     bool isSet() const { return kind() != NotSet; }
  75     bool operator!() const { return !isSet(); }
  76
  77     Structure* structure() const
  78     {
  79         ASSERT(kind() == Replace);
  80         return m_oldStructure;
  81     }
  82
  83     Structure* oldStructure() const
  84     {
  85         ASSERT(kind() == Transition || kind() == Replace);
  86         return m_oldStructure;
  87     }
  88
  89     Structure* newStructure() const
  90     {
  91         ASSERT(kind() == Transition);
  92         return m_newStructure;
  93     }
  94
  95     IntendedStructureChain* structureChain() const
  96     {
  97         ASSERT(kind() == Transition);
  98         return m_structureChain.get();
  99     }
 100
 101     PropertyOffset offset() const
 102     {
 103         ASSERT(isSet());
 104         return m_offset;
 105     }
 106
 107     void dump(PrintStream&) const;
 108     void dumpInContext(PrintStream&, DumpContext*) const;
 109
 110 private:
 111     Kind m_kind;
 112     Structure* m_oldStructure;
 113     Structure* m_newStructure;
 114     RefPtr<IntendedStructureChain> m_structureChain;
 115     PropertyOffset m_offset;
 116 };
 117
 118 } // namespace JSC
 119
 120 #endif // PutByIdVariant_h
 121