1 | /* |
2 | * Copyright (C) 2007, 2008 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 | * |
8 | * 1. Redistributions of source code must retain the above copyright |
9 | * notice, this list of conditions and the following disclaimer. |
10 | * 2. Redistributions in binary form must reproduce the above copyright |
11 | * notice, this list of conditions and the following disclaimer in the |
12 | * documentation and/or other materials provided with the distribution. |
13 | * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of |
14 | * its contributors may be used to endorse or promote products derived |
15 | * from this software without specific prior written permission. |
16 | * |
17 | * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
18 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
19 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
20 | * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
21 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
22 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
23 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
24 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
27 | */ |
28 | |
29 | #ifndef JSVariableObject_h |
30 | #define JSVariableObject_h |
31 | |
32 | #include "JSObject.h" |
33 | #include "Register.h" |
34 | #include "SymbolTable.h" |
35 | #include "UnusedParam.h" |
36 | #include <wtf/OwnArrayPtr.h> |
37 | #include <wtf/UnusedParam.h> |
38 | |
39 | namespace JSC { |
40 | |
41 | class Register; |
42 | |
43 | class JSVariableObject : public JSObject { |
44 | friend class JIT; |
45 | |
46 | public: |
47 | SymbolTable& symbolTable() const { return *d->symbolTable; } |
48 | |
49 | virtual void putWithAttributes(ExecState*, const Identifier&, JSValue, unsigned attributes) = 0; |
50 | |
51 | virtual bool deleteProperty(ExecState*, const Identifier&); |
52 | virtual void getOwnPropertyNames(ExecState*, PropertyNameArray&, EnumerationMode mode = ExcludeDontEnumProperties); |
53 | |
54 | virtual bool isVariableObject() const; |
55 | virtual bool isDynamicScope() const = 0; |
56 | |
57 | Register& registerAt(int index) const { return d->registers[index]; } |
58 | |
59 | static PassRefPtr<Structure> createStructure(JSValue prototype) |
60 | { |
61 | return Structure::create(prototype, typeInfo: TypeInfo(ObjectType, StructureFlags)); |
62 | } |
63 | |
64 | protected: |
65 | static const unsigned StructureFlags = OverridesGetPropertyNames | JSObject::StructureFlags; |
66 | // Subclasses of JSVariableObject can subclass this struct to add data |
67 | // without increasing their own size (since there's a hard limit on the |
68 | // size of a JSCell). |
69 | struct JSVariableObjectData { |
70 | JSVariableObjectData(SymbolTable* symbolTable, Register* registers) |
71 | : symbolTable(symbolTable) |
72 | , registers(registers) |
73 | { |
74 | ASSERT(symbolTable); |
75 | } |
76 | |
77 | SymbolTable* symbolTable; // Maps name -> offset from "r" in register file. |
78 | Register* registers; // "r" in the register file. |
79 | OwnArrayPtr<Register> registerArray; // Independent copy of registers, used when a variable object copies its registers out of the register file. |
80 | |
81 | private: |
82 | JSVariableObjectData(const JSVariableObjectData&); |
83 | JSVariableObjectData& operator=(const JSVariableObjectData&); |
84 | }; |
85 | |
86 | JSVariableObject(NonNullPassRefPtr<Structure> structure, JSVariableObjectData* data) |
87 | : JSObject(structure) |
88 | , d(data) // Subclass owns this pointer. |
89 | { |
90 | } |
91 | |
92 | Register* copyRegisterArray(Register* src, size_t count); |
93 | void setRegisters(Register* r, Register* registerArray); |
94 | |
95 | bool symbolTableGet(const Identifier&, PropertySlot&); |
96 | bool symbolTableGet(const Identifier&, PropertyDescriptor&); |
97 | bool symbolTableGet(const Identifier&, PropertySlot&, bool& slotIsWriteable); |
98 | bool symbolTablePut(const Identifier&, JSValue); |
99 | bool symbolTablePutWithAttributes(const Identifier&, JSValue, unsigned attributes); |
100 | |
101 | JSVariableObjectData* d; |
102 | }; |
103 | |
104 | inline bool JSVariableObject::symbolTableGet(const Identifier& propertyName, PropertySlot& slot) |
105 | { |
106 | SymbolTableEntry entry = symbolTable().inlineGet(key: propertyName.ustring().rep()); |
107 | if (!entry.isNull()) { |
108 | slot.setRegisterSlot(®isterAt(index: entry.getIndex())); |
109 | return true; |
110 | } |
111 | return false; |
112 | } |
113 | |
114 | inline bool JSVariableObject::symbolTableGet(const Identifier& propertyName, PropertySlot& slot, bool& slotIsWriteable) |
115 | { |
116 | SymbolTableEntry entry = symbolTable().inlineGet(key: propertyName.ustring().rep()); |
117 | if (!entry.isNull()) { |
118 | slot.setRegisterSlot(®isterAt(index: entry.getIndex())); |
119 | slotIsWriteable = !entry.isReadOnly(); |
120 | return true; |
121 | } |
122 | return false; |
123 | } |
124 | |
125 | inline bool JSVariableObject::symbolTablePut(const Identifier& propertyName, JSValue value) |
126 | { |
127 | ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this)); |
128 | |
129 | SymbolTableEntry entry = symbolTable().inlineGet(key: propertyName.ustring().rep()); |
130 | if (entry.isNull()) |
131 | return false; |
132 | if (entry.isReadOnly()) |
133 | return true; |
134 | registerAt(index: entry.getIndex()) = value; |
135 | return true; |
136 | } |
137 | |
138 | inline bool JSVariableObject::symbolTablePutWithAttributes(const Identifier& propertyName, JSValue value, unsigned attributes) |
139 | { |
140 | ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this)); |
141 | |
142 | SymbolTable::iterator iter = symbolTable().find(key: propertyName.ustring().rep()); |
143 | if (iter == symbolTable().end()) |
144 | return false; |
145 | SymbolTableEntry& entry = iter->second; |
146 | ASSERT(!entry.isNull()); |
147 | entry.setAttributes(attributes); |
148 | registerAt(index: entry.getIndex()) = value; |
149 | return true; |
150 | } |
151 | |
152 | inline Register* JSVariableObject::copyRegisterArray(Register* src, size_t count) |
153 | { |
154 | Register* registerArray = new Register[count]; |
155 | memcpy(dest: registerArray, src: src, n: count * sizeof(Register)); |
156 | |
157 | return registerArray; |
158 | } |
159 | |
160 | inline void JSVariableObject::setRegisters(Register* registers, Register* registerArray) |
161 | { |
162 | ASSERT(registerArray != d->registerArray.get()); |
163 | d->registerArray.set(registerArray); |
164 | d->registers = registers; |
165 | } |
166 | |
167 | } // namespace JSC |
168 | |
169 | #endif // JSVariableObject_h |
170 | |