dfg/DFGBasicBlock.h

   1 /*
   2  * Copyright (C) 2011 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 DFGBasicBlock_h
  27 #define DFGBasicBlock_h
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "DFGAbstractValue.h"
  32 #include "DFGNode.h"
  33 #include "Operands.h"
  34 #include <wtf/OwnPtr.h>
  35 #include <wtf/Vector.h>
  36
  37 namespace JSC { namespace DFG {
  38
  39 typedef Vector <BlockIndex, 2> PredecessorList;
  40
  41 struct BasicBlock : Vector<NodeIndex, 8> {
  42     BasicBlock(unsigned bytecodeBegin, unsigned numArguments, unsigned numLocals)
  43         : bytecodeBegin(bytecodeBegin)
  44         , isOSRTarget(false)
  45         , cfaHasVisited(false)
  46         , cfaShouldRevisit(false)
  47 #if !ASSERT_DISABLED
  48         , isLinked(false)
  49 #endif
  50         , isReachable(false)
  51         , variablesAtHead(numArguments, numLocals)
  52         , variablesAtTail(numArguments, numLocals)
  53         , valuesAtHead(numArguments, numLocals)
  54         , valuesAtTail(numArguments, numLocals)
  55     {
  56     }
  57
  58     void ensureLocals(unsigned newNumLocals)
  59     {
  60         variablesAtHead.ensureLocals(newNumLocals);
  61         variablesAtTail.ensureLocals(newNumLocals);
  62         valuesAtHead.ensureLocals(newNumLocals);
  63         valuesAtTail.ensureLocals(newNumLocals);
  64     }
  65
  66     // This value is used internally for block linking and OSR entry. It is mostly meaningless
  67     // for other purposes due to inlining.
  68     unsigned bytecodeBegin;
  69
  70     bool isOSRTarget;
  71     bool cfaHasVisited;
  72     bool cfaShouldRevisit;
  73 #if !ASSERT_DISABLED
  74     bool isLinked;
  75 #endif
  76     bool isReachable;
  77
  78     Vector<NodeIndex> phis;
  79     PredecessorList m_predecessors;
  80
  81     Operands<NodeIndex, NodeIndexTraits> variablesAtHead;
  82     Operands<NodeIndex, NodeIndexTraits> variablesAtTail;
  83
  84     Operands<AbstractValue> valuesAtHead;
  85     Operands<AbstractValue> valuesAtTail;
  86 };
  87
  88 struct UnlinkedBlock {
  89     BlockIndex m_blockIndex;
  90     bool m_needsNormalLinking;
  91     bool m_needsEarlyReturnLinking;
  92
  93     UnlinkedBlock() { }
  94
  95     explicit UnlinkedBlock(BlockIndex blockIndex)
  96         : m_blockIndex(blockIndex)
  97         , m_needsNormalLinking(true)
  98         , m_needsEarlyReturnLinking(false)
  99     {
 100     }
 101 };
 102
 103 } } // namespace JSC::DFG
 104
 105 #endif // ENABLE(DFG_JIT)
 106
 107 #endif // DFGBasicBlock_h
 108