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 JSNonFinalObject { 44 friend class JIT; 45 46 public: 47 SymbolTable& symbolTable() const { return *m_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(bool& requiresDynamicChecks) const = 0; 56 57 WriteBarrier<Unknown>& registerAt(int index) const { return m_registers[index]; } 58 59 WriteBarrier<Unknown>* const * addressOfRegisters() const { return &m_registers; } 60 61 static Structure* createStructure(JSGlobalData& globalData, JSValue prototype) 62 { 63 return Structure::create(globalData, prototype, TypeInfo(ObjectType, StructureFlags), AnonymousSlotCount, &s_info); 64 } 65 66 protected: 67 static const unsigned StructureFlags = OverridesGetPropertyNames | JSObject::StructureFlags; 68 69 JSVariableObject(JSGlobalData& globalData, Structure* structure, SymbolTable* symbolTable, Register* registers) 70 : JSNonFinalObject(globalData, structure) 71 , m_symbolTable(symbolTable) 72 , m_registers(reinterpret_cast<WriteBarrier<Unknown>*>(registers)) 73 { 74 ASSERT(m_symbolTable); 75 COMPILE_ASSERT(sizeof(WriteBarrier<Unknown>) == sizeof(Register), Register_should_be_same_size_as_WriteBarrier); 76 } 77 78 PassOwnArrayPtr<WriteBarrier<Unknown> > copyRegisterArray(JSGlobalData&, WriteBarrier<Unknown>* src, size_t count, size_t callframeStarts); 79 void setRegisters(WriteBarrier<Unknown>* registers, PassOwnArrayPtr<WriteBarrier<Unknown> > registerArray); 80 81 bool symbolTableGet(const Identifier&, PropertySlot&); 82 bool symbolTableGet(const Identifier&, PropertyDescriptor&); 83 bool symbolTableGet(const Identifier&, PropertySlot&, bool& slotIsWriteable); 84 bool symbolTablePut(JSGlobalData&, const Identifier&, JSValue); 85 bool symbolTablePutWithAttributes(JSGlobalData&, const Identifier&, JSValue, unsigned attributes); 86 87 SymbolTable* m_symbolTable; // Maps name -> offset from "r" in register file. 88 WriteBarrier<Unknown>* m_registers; // "r" in the register file. 89 OwnArrayPtr<WriteBarrier<Unknown> > m_registerArray; // Independent copy of registers, used when a variable object copies its registers out of the register file. 90 }; 91 92 inline bool JSVariableObject::symbolTableGet(const Identifier& propertyName, PropertySlot& slot) 93 { 94 SymbolTableEntry entry = symbolTable().inlineGet(propertyName.impl()); 95 if (!entry.isNull()) { 96 slot.setValue(registerAt(entry.getIndex()).get()); 97 return true; 98 } 99 return false; 100 } 101 102 inline bool JSVariableObject::symbolTableGet(const Identifier& propertyName, PropertySlot& slot, bool& slotIsWriteable) 103 { 104 SymbolTableEntry entry = symbolTable().inlineGet(propertyName.impl()); 105 if (!entry.isNull()) { 106 slot.setValue(registerAt(entry.getIndex()).get()); 107 slotIsWriteable = !entry.isReadOnly(); 108 return true; 109 } 110 return false; 111 } 112 113 inline bool JSVariableObject::symbolTablePut(JSGlobalData& globalData, const Identifier& propertyName, JSValue value) 114 { 115 ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this)); 116 117 SymbolTableEntry entry = symbolTable().inlineGet(propertyName.impl()); 118 if (entry.isNull()) 119 return false; 120 if (entry.isReadOnly()) 121 return true; 122 registerAt(entry.getIndex()).set(globalData, this, value); 123 return true; 124 } 125 126 inline bool JSVariableObject::symbolTablePutWithAttributes(JSGlobalData& globalData, const Identifier& propertyName, JSValue value, unsigned attributes) 127 { 128 ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this)); 129 130 SymbolTable::iterator iter = symbolTable().find(propertyName.impl()); 131 if (iter == symbolTable().end()) 132 return false; 133 SymbolTableEntry& entry = iter->second; 134 ASSERT(!entry.isNull()); 135 entry.setAttributes(attributes); 136 registerAt(entry.getIndex()).set(globalData, this, value); 137 return true; 138 } 139 140 inline PassOwnArrayPtr<WriteBarrier<Unknown> > JSVariableObject::copyRegisterArray(JSGlobalData& globalData, WriteBarrier<Unknown>* src, size_t count, size_t callframeStarts) 141 { 142 OwnArrayPtr<WriteBarrier<Unknown> > registerArray = adoptArrayPtr(new WriteBarrier<Unknown>[count]); 143 for (size_t i = 0; i < callframeStarts; i++) 144 registerArray[i].set(globalData, this, src[i].get()); 145 for (size_t i = callframeStarts + RegisterFile::CallFrameHeaderSize; i < count; i++) 146 registerArray[i].set(globalData, this, src[i].get()); 147 148 return registerArray.release(); 149 } 150 151 inline void JSVariableObject::setRegisters(WriteBarrier<Unknown>* registers, PassOwnArrayPtr<WriteBarrier<Unknown> > registerArray) 152 { 153 ASSERT(registerArray != m_registerArray); 154 m_registerArray = registerArray; 155 m_registers = registers; 156 } 157 158 } // namespace JSC 159 160 #endif // JSVariableObject_h 161