dfg/DFGAdjacencyList.h

   1 /*
   2  * Copyright (C) 2011, 2013 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 DFGAdjacencyList_h
  27 #define DFGAdjacencyList_h
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "DFGCommon.h"
  32 #include "DFGEdge.h"
  33
  34 namespace JSC { namespace DFG {
  35
  36 class AdjacencyList {
  37 public:
  38     enum Kind {
  39         Fixed,
  40         Variable
  41     };
  42
  43     enum { Size = 3 };
  44
  45     AdjacencyList() { }
  46
  47     AdjacencyList(Kind kind)
  48     {
  49         if (kind == Variable) {
  50             m_words[0].m_encodedWord = UINT_MAX;
  51             m_words[1].m_encodedWord = UINT_MAX;
  52         }
  53     }
  54
  55     AdjacencyList(Kind kind, Edge child1, Edge child2, Edge child3)
  56     {
  57         ASSERT_UNUSED(kind, kind == Fixed);
  58         initialize(child1, child2, child3);
  59     }
  60
  61     AdjacencyList(Kind kind, unsigned firstChild, unsigned numChildren)
  62     {
  63         ASSERT_UNUSED(kind, kind == Variable);
  64         setFirstChild(firstChild);
  65         setNumChildren(numChildren);
  66     }
  67
  68     const Edge& child(unsigned i) const
  69     {
  70         ASSERT(i < Size);
  71         return m_words[i];
  72     }
  73
  74     Edge& child(unsigned i)
  75     {
  76         ASSERT(i < Size);
  77         return m_words[i];
  78     }
  79
  80     void setChild(unsigned i, Edge nodeUse)
  81     {
  82         ASSERT(i < Size);
  83         m_words[i] = nodeUse;
  84     }
  85
  86     Edge child1() const { return child(0); }
  87     Edge child2() const { return child(1); }
  88     Edge child3() const { return child(2); }
  89
  90     Edge& child1() { return child(0); }
  91     Edge& child2() { return child(1); }
  92     Edge& child3() { return child(2); }
  93
  94     void setChild1(Edge nodeUse) { setChild(0, nodeUse); }
  95     void setChild2(Edge nodeUse) { setChild(1, nodeUse); }
  96     void setChild3(Edge nodeUse) { setChild(2, nodeUse); }
  97
  98     Edge child1Unchecked() const { return m_words[0]; }
  99
 100     Edge justOneChild() const
 101     {
 102         if (!!child1() && !child2()) {
 103             ASSERT(!child3());
 104             return child1();
 105         }
 106         return Edge();
 107     }
 108
 109     void initialize(Edge child1, Edge child2, Edge child3)
 110     {
 111         child(0) = child1;
 112         child(1) = child2;
 113         child(2) = child3;
 114     }
 115
 116     void initialize(Node* child1 = 0, Node* child2 = 0, Node* child3 = 0)
 117     {
 118         initialize(Edge(child1), Edge(child2), Edge(child3));
 119     }
 120
 121     void reset()
 122     {
 123         initialize();
 124     }
 125
 126     // Call this if you wish to remove an edge and the node treats the list of children.
 127     void removeEdge(unsigned edgeIndex)
 128     {
 129         for (unsigned i = edgeIndex; i < Size - 1; ++i)
 130             setChild(i, child(i + 1));
 131         setChild(Size - 1, Edge());
 132     }
 133
 134     unsigned firstChild() const
 135     {
 136         return m_words[0].m_encodedWord;
 137     }
 138     void setFirstChild(unsigned firstChild)
 139     {
 140         m_words[0].m_encodedWord = firstChild;
 141     }
 142
 143     unsigned numChildren() const
 144     {
 145         return m_words[1].m_encodedWord;
 146     }
 147     void setNumChildren(unsigned numChildren)
 148     {
 149         m_words[1].m_encodedWord = numChildren;
 150     }
 151
 152 private:
 153     Edge m_words[Size];
 154 };
 155
 156 } } // namespace JSC::DFG
 157
 158 #endif // ENABLE(DFG_JIT)
 159
 160 #endif // DFGAdjacencyList_h