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 DFGBasicBlock_h
27#define DFGBasicBlock_h
28
29#if ENABLE(DFG_JIT)
30
31#include "DFGAbstractValue.h"
32#include "DFGBranchDirection.h"
33#include "DFGNode.h"
34#include "DFGVariadicFunction.h"
35#include "Operands.h"
36#include <wtf/OwnPtr.h>
37#include <wtf/Vector.h>
38
39namespace JSC { namespace DFG {
40
41class Graph;
42
43typedef Vector <BlockIndex, 2> PredecessorList;
44
45struct BasicBlock : Vector<Node*, 8> {
46    BasicBlock(unsigned bytecodeBegin, unsigned numArguments, unsigned numLocals)
47        : bytecodeBegin(bytecodeBegin)
48        , isOSRTarget(false)
49        , cfaHasVisited(false)
50        , cfaShouldRevisit(false)
51        , cfaFoundConstants(false)
52        , cfaDidFinish(true)
53        , cfaBranchDirection(InvalidBranchDirection)
54#if !ASSERT_DISABLED
55        , isLinked(false)
56#endif
57        , isReachable(false)
58        , variablesAtHead(numArguments, numLocals)
59        , variablesAtTail(numArguments, numLocals)
60        , valuesAtHead(numArguments, numLocals)
61        , valuesAtTail(numArguments, numLocals)
62    {
63    }
64
65    ~BasicBlock()
66    {
67    }
68
69    void ensureLocals(unsigned newNumLocals)
70    {
71        variablesAtHead.ensureLocals(newNumLocals);
72        variablesAtTail.ensureLocals(newNumLocals);
73        valuesAtHead.ensureLocals(newNumLocals);
74        valuesAtTail.ensureLocals(newNumLocals);
75    }
76
77    size_t numNodes() const { return phis.size() + size(); }
78    Node* node(size_t i) const
79    {
80        if (i < phis.size())
81            return phis[i];
82        return at(i - phis.size());
83    }
84    bool isPhiIndex(size_t i) const { return i < phis.size(); }
85
86    bool isInPhis(Node* node) const
87    {
88        for (size_t i = 0; i < phis.size(); ++i) {
89            if (phis[i] == node)
90                return true;
91        }
92        return false;
93    }
94
95    bool isInBlock(Node* myNode) const
96    {
97        for (size_t i = 0; i < numNodes(); ++i) {
98            if (node(i) == myNode)
99                return true;
100        }
101        return false;
102    }
103
104#define DFG_DEFINE_APPEND_NODE(templatePre, templatePost, typeParams, valueParamsComma, valueParams, valueArgs) \
105    templatePre typeParams templatePost Node* appendNode(Graph&, SpeculatedType valueParamsComma valueParams);
106    DFG_VARIADIC_TEMPLATE_FUNCTION(DFG_DEFINE_APPEND_NODE)
107#undef DFG_DEFINE_APPEND_NODE
108
109    // This value is used internally for block linking and OSR entry. It is mostly meaningless
110    // for other purposes due to inlining.
111    unsigned bytecodeBegin;
112
113    bool isOSRTarget;
114    bool cfaHasVisited;
115    bool cfaShouldRevisit;
116    bool cfaFoundConstants;
117    bool cfaDidFinish;
118    BranchDirection cfaBranchDirection;
119#if !ASSERT_DISABLED
120    bool isLinked;
121#endif
122    bool isReachable;
123
124    Vector<Node*> phis;
125    PredecessorList m_predecessors;
126
127    Operands<Node*, NodePointerTraits> variablesAtHead;
128    Operands<Node*, NodePointerTraits> variablesAtTail;
129
130    Operands<AbstractValue> valuesAtHead;
131    Operands<AbstractValue> valuesAtTail;
132};
133
134struct UnlinkedBlock {
135    BlockIndex m_blockIndex;
136    bool m_needsNormalLinking;
137    bool m_needsEarlyReturnLinking;
138
139    UnlinkedBlock() { }
140
141    explicit UnlinkedBlock(BlockIndex blockIndex)
142        : m_blockIndex(blockIndex)
143        , m_needsNormalLinking(true)
144        , m_needsEarlyReturnLinking(false)
145    {
146    }
147};
148
149} } // namespace JSC::DFG
150
151#endif // ENABLE(DFG_JIT)
152
153#endif // DFGBasicBlock_h
154
155