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diff --git a/Source/JavaScriptCore/dfg/DFGGraph.h b/Source/JavaScriptCore/dfg/DFGGraph.h
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+++ b/Source/JavaScriptCore/dfg/DFGGraph.h
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+/*
+ * Copyright (C) 2011 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef DFGGraph_h
+#define DFGGraph_h
+
+#if ENABLE(DFG_JIT)
+
+#include "CodeBlock.h"
+#include "DFGBasicBlock.h"
+#include "DFGNode.h"
+#include "PredictionTracker.h"
+#include "RegisterFile.h"
+#include <wtf/BitVector.h>
+#include <wtf/HashMap.h>
+#include <wtf/Vector.h>
+#include <wtf/StdLibExtras.h>
+
+namespace JSC {
+
+class CodeBlock;
+class ExecState;
+
+namespace DFG {
+
+struct StorageAccessData {
+    size_t offset;
+    unsigned identifierNumber;
+    
+    // NOTE: the offset and identifierNumber do not by themselves
+    // uniquely identify a property. The identifierNumber and a
+    // Structure* do. If those two match, then the offset should
+    // be the same, as well. For any Node that has a StorageAccessData,
+    // it is possible to retrieve the Structure* by looking at the
+    // first child. It should be a CheckStructure, which has the
+    // Structure*.
+};
+
+struct ResolveGlobalData {
+    unsigned identifierNumber;
+    unsigned resolveInfoIndex;
+};
+
+// 
+// === Graph ===
+//
+// The dataflow graph is an ordered vector of nodes.
+// The order may be significant for nodes with side-effects (property accesses, value conversions).
+// Nodes that are 'dead' remain in the vector with refCount 0.
+class Graph : public Vector<Node, 64> {
+public:
+    // Mark a node as being referenced.
+    void ref(NodeIndex nodeIndex)
+    {
+        Node& node = at(nodeIndex);
+        // If the value (before incrementing) was at refCount zero then we need to ref its children.
+        if (node.ref())
+            refChildren(nodeIndex);
+    }
+    
+    void deref(NodeIndex nodeIndex)
+    {
+        if (at(nodeIndex).deref())
+            derefChildren(nodeIndex);
+    }
+    
+    void clearAndDerefChild1(Node& node)
+    {
+        if (node.children.fixed.child1 == NoNode)
+            return;
+        deref(node.children.fixed.child1);
+        node.children.fixed.child1 = NoNode;
+    }
+
+    void clearAndDerefChild2(Node& node)
+    {
+        if (node.children.fixed.child2 == NoNode)
+            return;
+        deref(node.children.fixed.child2);
+        node.children.fixed.child2 = NoNode;
+    }
+
+    void clearAndDerefChild3(Node& node)
+    {
+        if (node.children.fixed.child3 == NoNode)
+            return;
+        deref(node.children.fixed.child3);
+        node.children.fixed.child3 = NoNode;
+    }
+
+#ifndef NDEBUG
+    // CodeBlock is optional, but may allow additional information to be dumped (e.g. Identifier names).
+    void dump(CodeBlock* = 0);
+    void dump(NodeIndex, CodeBlock* = 0);
+
+    // Dump the code origin of the given node as a diff from the code origin of the
+    // preceding node.
+    void dumpCodeOrigin(NodeIndex);
+#endif
+
+    BlockIndex blockIndexForBytecodeOffset(Vector<BlockIndex>& blocks, unsigned bytecodeBegin);
+
+    bool predictGlobalVar(unsigned varNumber, PredictedType prediction)
+    {
+        return m_predictions.predictGlobalVar(varNumber, prediction);
+    }
+    
+    PredictedType getGlobalVarPrediction(unsigned varNumber)
+    {
+        return m_predictions.getGlobalVarPrediction(varNumber);
+    }
+    
+    PredictedType getJSConstantPrediction(Node& node, CodeBlock* codeBlock)
+    {
+        return predictionFromValue(node.valueOfJSConstant(codeBlock));
+    }
+    
+    // Helper methods to check nodes for constants.
+    bool isConstant(NodeIndex nodeIndex)
+    {
+        return at(nodeIndex).hasConstant();
+    }
+    bool isJSConstant(NodeIndex nodeIndex)
+    {
+        return at(nodeIndex).hasConstant();
+    }
+    bool isInt32Constant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return at(nodeIndex).isInt32Constant(codeBlock);
+    }
+    bool isDoubleConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return at(nodeIndex).isDoubleConstant(codeBlock);
+    }
+    bool isNumberConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return at(nodeIndex).isNumberConstant(codeBlock);
+    }
+    bool isBooleanConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return at(nodeIndex).isBooleanConstant(codeBlock);
+    }
+    bool isFunctionConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        if (!isJSConstant(nodeIndex))
+            return false;
+        if (!getJSFunction(valueOfJSConstant(codeBlock, nodeIndex)))
+            return false;
+        return true;
+    }
+    // Helper methods get constant values from nodes.
+    JSValue valueOfJSConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return at(nodeIndex).valueOfJSConstant(codeBlock);
+    }
+    int32_t valueOfInt32Constant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return valueOfJSConstant(codeBlock, nodeIndex).asInt32();
+    }
+    double valueOfNumberConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return valueOfJSConstant(codeBlock, nodeIndex).asNumber();
+    }
+    bool valueOfBooleanConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        return valueOfJSConstant(codeBlock, nodeIndex).asBoolean();
+    }
+    JSFunction* valueOfFunctionConstant(CodeBlock* codeBlock, NodeIndex nodeIndex)
+    {
+        JSCell* function = getJSFunction(valueOfJSConstant(codeBlock, nodeIndex));
+        ASSERT(function);
+        return asFunction(function);
+    }
+
+#ifndef NDEBUG
+    static const char *opName(NodeType);
+    
+    // This is O(n), and should only be used for verbose dumps.
+    const char* nameOfVariableAccessData(VariableAccessData*);
+#endif
+
+    void predictArgumentTypes(CodeBlock*);
+    
+    StructureSet* addStructureSet(const StructureSet& structureSet)
+    {
+        ASSERT(structureSet.size());
+        m_structureSet.append(structureSet);
+        return &m_structureSet.last();
+    }
+    
+    StructureTransitionData* addStructureTransitionData(const StructureTransitionData& structureTransitionData)
+    {
+        m_structureTransitionData.append(structureTransitionData);
+        return &m_structureTransitionData.last();
+    }
+    
+    ValueProfile* valueProfileFor(NodeIndex nodeIndex, CodeBlock* profiledBlock)
+    {
+        if (nodeIndex == NoNode)
+            return 0;
+        
+        Node& node = at(nodeIndex);
+        
+        switch (node.op) {
+        case GetLocal: {
+            if (!operandIsArgument(node.local()))
+                return 0;
+            int argument = operandToArgument(node.local());
+            if (node.variableAccessData() != at(m_arguments[argument]).variableAccessData())
+                return 0;
+            return profiledBlock->valueProfileForArgument(argument);
+        }
+        
+        // Nodes derives from calls need special handling because the value profile is
+        // associated with the op_call_put_result instruction.
+        case Call:
+        case Construct:
+        case ArrayPop:
+        case ArrayPush: {
+            ASSERT(OPCODE_LENGTH(op_call) == OPCODE_LENGTH(op_construct));
+            return profiledBlock->valueProfileForBytecodeOffset(node.codeOrigin.bytecodeIndex + OPCODE_LENGTH(op_call));
+        }
+
+        default:
+            if (node.hasHeapPrediction())
+                return profiledBlock->valueProfileForBytecodeOffset(node.codeOrigin.bytecodeIndex);
+            return 0;
+        }
+    }
+
+    Vector< OwnPtr<BasicBlock> , 8> m_blocks;
+    Vector<NodeIndex, 16> m_varArgChildren;
+    Vector<StorageAccessData> m_storageAccessData;
+    Vector<ResolveGlobalData> m_resolveGlobalData;
+    Vector<NodeIndex, 8> m_arguments;
+    SegmentedVector<VariableAccessData, 16> m_variableAccessData;
+    SegmentedVector<StructureSet, 16> m_structureSet;
+    SegmentedVector<StructureTransitionData, 8> m_structureTransitionData;
+    BitVector m_preservedVars;
+    unsigned m_localVars;
+    unsigned m_parameterSlots;
+private:
+    
+    // When a node's refCount goes from 0 to 1, it must (logically) recursively ref all of its children, and vice versa.
+    void refChildren(NodeIndex);
+    void derefChildren(NodeIndex);
+
+    PredictionTracker m_predictions;
+};
+
+class GetBytecodeBeginForBlock {
+public:
+    GetBytecodeBeginForBlock(Graph& graph)
+        : m_graph(graph)
+    {
+    }
+    
+    unsigned operator()(BlockIndex* blockIndex) const
+    {
+        return m_graph.m_blocks[*blockIndex]->bytecodeBegin;
+    }
+
+private:
+    Graph& m_graph;
+};
+
+inline BlockIndex Graph::blockIndexForBytecodeOffset(Vector<BlockIndex>& linkingTargets, unsigned bytecodeBegin)
+{
+    return *WTF::binarySearchWithFunctor<BlockIndex, unsigned>(linkingTargets.begin(), linkingTargets.size(), bytecodeBegin, WTF::KeyMustBePresentInArray, GetBytecodeBeginForBlock(*this));
+}
+
+} } // namespace JSC::DFG
+
+#endif
+#endif