da55c0191e40c00cf5990b014f3119f84dff3e62
[WebKit-https.git] / Source / JavaScriptCore / runtime / JSGlobalObject.cpp
1 /*
2  * Copyright (C) 2007, 2008, 2009 Apple Inc. All rights reserved.
3  * Copyright (C) 2008 Cameron Zwarich (cwzwarich@uwaterloo.ca)
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1.  Redistributions of source code must retain the above copyright
10  *     notice, this list of conditions and the following disclaimer. 
11  * 2.  Redistributions in binary form must reproduce the above copyright
12  *     notice, this list of conditions and the following disclaimer in the
13  *     documentation and/or other materials provided with the distribution. 
14  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
15  *     its contributors may be used to endorse or promote products derived
16  *     from this software without specific prior written permission. 
17  *
18  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29
30 #include "config.h"
31 #include "JSGlobalObject.h"
32
33 #include "JSCallbackConstructor.h"
34 #include "JSCallbackFunction.h"
35 #include "JSCallbackObject.h"
36
37 #include "Arguments.h"
38 #include "ArrayConstructor.h"
39 #include "ArrayPrototype.h"
40 #include "BooleanConstructor.h"
41 #include "BooleanPrototype.h"
42 #include "CodeBlock.h"
43 #include "DateConstructor.h"
44 #include "DatePrototype.h"
45 #include "Error.h"
46 #include "ErrorConstructor.h"
47 #include "ErrorPrototype.h"
48 #include "FunctionConstructor.h"
49 #include "FunctionPrototype.h"
50 #include "GetterSetter.h"
51 #include "JSBoundFunction.h"
52 #include "JSFunction.h"
53 #include "JSGlobalObjectFunctions.h"
54 #include "JSLock.h"
55 #include "JSONObject.h"
56 #include "Interpreter.h"
57 #include "Lookup.h"
58 #include "MathObject.h"
59 #include "NativeErrorConstructor.h"
60 #include "NativeErrorPrototype.h"
61 #include "NumberConstructor.h"
62 #include "NumberPrototype.h"
63 #include "ObjectConstructor.h"
64 #include "ObjectPrototype.h"
65 #include "Profiler.h"
66 #include "RegExpConstructor.h"
67 #include "RegExpMatchesArray.h"
68 #include "RegExpObject.h"
69 #include "RegExpPrototype.h"
70 #include "ScopeChainMark.h"
71 #include "StringConstructor.h"
72 #include "StringPrototype.h"
73 #include "Debugger.h"
74
75 #include "JSGlobalObject.lut.h"
76
77 namespace JSC {
78
79 const ClassInfo JSGlobalObject::s_info = { "GlobalObject", &JSVariableObject::s_info, 0, ExecState::globalObjectTable, CREATE_METHOD_TABLE(JSGlobalObject) };
80
81 const GlobalObjectMethodTable JSGlobalObject::s_globalObjectMethodTable = { &allowsAccessFrom, &supportsProfiling, &supportsRichSourceInfo, &shouldInterruptScript };
82
83 /* Source for JSGlobalObject.lut.h
84 @begin globalObjectTable
85   parseInt              globalFuncParseInt              DontEnum|Function 2
86   parseFloat            globalFuncParseFloat            DontEnum|Function 1
87   isNaN                 globalFuncIsNaN                 DontEnum|Function 1
88   isFinite              globalFuncIsFinite              DontEnum|Function 1
89   escape                globalFuncEscape                DontEnum|Function 1
90   unescape              globalFuncUnescape              DontEnum|Function 1
91   decodeURI             globalFuncDecodeURI             DontEnum|Function 1
92   decodeURIComponent    globalFuncDecodeURIComponent    DontEnum|Function 1
93   encodeURI             globalFuncEncodeURI             DontEnum|Function 1
94   encodeURIComponent    globalFuncEncodeURIComponent    DontEnum|Function 1
95 @end
96 */
97
98 ASSERT_CLASS_FITS_IN_CELL(JSGlobalObject);
99
100 // Default number of ticks before a timeout check should be done.
101 static const int initialTickCountThreshold = 255;
102
103 // Preferred number of milliseconds between each timeout check
104 static const int preferredScriptCheckTimeInterval = 1000;
105
106 template <typename T> static inline void visitIfNeeded(SlotVisitor& visitor, WriteBarrier<T>* v)
107 {
108     if (*v)
109         visitor.append(v);
110 }
111
112 JSGlobalObject::~JSGlobalObject()
113 {
114     ASSERT(JSLock::currentThreadIsHoldingLock());
115
116     if (m_debugger)
117         m_debugger->detach(this);
118
119     Profiler** profiler = Profiler::enabledProfilerReference();
120     if (UNLIKELY(*profiler != 0)) {
121         (*profiler)->stopProfiling(this);
122     }
123 }
124
125 void JSGlobalObject::destroy(JSCell* cell)
126 {
127     jsCast<JSGlobalObject*>(cell)->JSGlobalObject::~JSGlobalObject();
128 }
129
130 void JSGlobalObject::init(JSObject* thisValue)
131 {
132     ASSERT(JSLock::currentThreadIsHoldingLock());
133     
134     structure()->disableSpecificFunctionTracking();
135
136     m_globalScopeChain.set(globalData(), this, ScopeChainNode::create(0, this, &globalData(), this, thisValue));
137
138     JSGlobalObject::globalExec()->init(0, 0, m_globalScopeChain.get(), CallFrame::noCaller(), 0, 0);
139
140     m_debugger = 0;
141
142     reset(prototype());
143 }
144
145 void JSGlobalObject::put(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
146 {
147     JSGlobalObject* thisObject = jsCast<JSGlobalObject*>(cell);
148     ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(thisObject));
149
150     if (thisObject->symbolTablePut(exec, propertyName, value, slot.isStrictMode()))
151         return;
152     JSVariableObject::put(thisObject, exec, propertyName, value, slot);
153 }
154
155 void JSGlobalObject::putDirectVirtual(JSObject* object, ExecState* exec, PropertyName propertyName, JSValue value, unsigned attributes)
156 {
157     JSGlobalObject* thisObject = jsCast<JSGlobalObject*>(object);
158     ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(thisObject));
159
160     if (thisObject->symbolTablePutWithAttributes(exec->globalData(), propertyName, value, attributes))
161         return;
162
163     JSValue valueBefore = thisObject->getDirect(exec->globalData(), propertyName);
164     PutPropertySlot slot;
165     JSVariableObject::put(thisObject, exec, propertyName, value, slot);
166     if (!valueBefore) {
167         JSValue valueAfter = thisObject->getDirect(exec->globalData(), propertyName);
168         if (valueAfter)
169             JSObject::putDirectVirtual(thisObject, exec, propertyName, valueAfter, attributes);
170     }
171 }
172
173 bool JSGlobalObject::defineOwnProperty(JSObject* object, ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor, bool shouldThrow)
174 {
175     JSGlobalObject* thisObject = jsCast<JSGlobalObject*>(object);
176     PropertySlot slot;
177     // silently ignore attempts to add accessors aliasing vars.
178     if (descriptor.isAccessorDescriptor() && thisObject->symbolTableGet(propertyName, slot))
179         return false;
180     return Base::defineOwnProperty(thisObject, exec, propertyName, descriptor, shouldThrow);
181 }
182
183
184 static inline JSObject* lastInPrototypeChain(JSObject* object)
185 {
186     JSObject* o = object;
187     while (o->prototype().isObject())
188         o = asObject(o->prototype());
189     return o;
190 }
191
192 void JSGlobalObject::reset(JSValue prototype)
193 {
194     ExecState* exec = JSGlobalObject::globalExec();
195
196     m_functionPrototype.set(exec->globalData(), this, FunctionPrototype::create(exec, this, FunctionPrototype::createStructure(exec->globalData(), this, jsNull()))); // The real prototype will be set once ObjectPrototype is created.
197     m_functionStructure.set(exec->globalData(), this, JSFunction::createStructure(exec->globalData(), this, m_functionPrototype.get()));
198     m_boundFunctionStructure.set(exec->globalData(), this, JSBoundFunction::createStructure(exec->globalData(), this, m_functionPrototype.get()));
199     m_namedFunctionStructure.set(exec->globalData(), this, Structure::addPropertyTransition(exec->globalData(), m_functionStructure.get(), exec->globalData().propertyNames->name, DontDelete | ReadOnly | DontEnum, 0, m_functionNameOffset));
200     m_internalFunctionStructure.set(exec->globalData(), this, InternalFunction::createStructure(exec->globalData(), this, m_functionPrototype.get()));
201     JSFunction* callFunction = 0;
202     JSFunction* applyFunction = 0;
203     m_functionPrototype->addFunctionProperties(exec, this, &callFunction, &applyFunction);
204     m_callFunction.set(exec->globalData(), this, callFunction);
205     m_applyFunction.set(exec->globalData(), this, applyFunction);
206     m_objectPrototype.set(exec->globalData(), this, ObjectPrototype::create(exec, this, ObjectPrototype::createStructure(exec->globalData(), this, jsNull())));
207     GetterSetter* protoAccessor = GetterSetter::create(exec);
208     protoAccessor->setGetter(exec->globalData(), JSFunction::create(exec, this, 0, "", globalFuncProtoGetter));
209     protoAccessor->setSetter(exec->globalData(), JSFunction::create(exec, this, 0, "", globalFuncProtoSetter));
210     m_objectPrototype->putDirectAccessor(exec->globalData(), exec->propertyNames().underscoreProto, protoAccessor, Accessor | DontEnum);
211     m_functionPrototype->structure()->setPrototypeWithoutTransition(exec->globalData(), m_objectPrototype.get());
212
213     m_emptyObjectStructure.set(exec->globalData(), this, m_objectPrototype->inheritorID(exec->globalData()));
214     m_nullPrototypeObjectStructure.set(exec->globalData(), this, createEmptyObjectStructure(exec->globalData(), this, jsNull()));
215
216     m_callbackFunctionStructure.set(exec->globalData(), this, JSCallbackFunction::createStructure(exec->globalData(), this, m_functionPrototype.get()));
217     m_argumentsStructure.set(exec->globalData(), this, Arguments::createStructure(exec->globalData(), this, m_objectPrototype.get()));
218     m_callbackConstructorStructure.set(exec->globalData(), this, JSCallbackConstructor::createStructure(exec->globalData(), this, m_objectPrototype.get()));
219     m_callbackObjectStructure.set(exec->globalData(), this, JSCallbackObject<JSNonFinalObject>::createStructure(exec->globalData(), this, m_objectPrototype.get()));
220
221     m_arrayPrototype.set(exec->globalData(), this, ArrayPrototype::create(exec, this, ArrayPrototype::createStructure(exec->globalData(), this, m_objectPrototype.get())));
222     m_arrayStructure.set(exec->globalData(), this, JSArray::createStructure(exec->globalData(), this, m_arrayPrototype.get()));
223     m_regExpMatchesArrayStructure.set(exec->globalData(), this, RegExpMatchesArray::createStructure(exec->globalData(), this, m_arrayPrototype.get()));
224
225     m_stringPrototype.set(exec->globalData(), this, StringPrototype::create(exec, this, StringPrototype::createStructure(exec->globalData(), this, m_objectPrototype.get())));
226     m_stringObjectStructure.set(exec->globalData(), this, StringObject::createStructure(exec->globalData(), this, m_stringPrototype.get()));
227
228     m_booleanPrototype.set(exec->globalData(), this, BooleanPrototype::create(exec, this, BooleanPrototype::createStructure(exec->globalData(), this, m_objectPrototype.get())));
229     m_booleanObjectStructure.set(exec->globalData(), this, BooleanObject::createStructure(exec->globalData(), this, m_booleanPrototype.get()));
230
231     m_numberPrototype.set(exec->globalData(), this, NumberPrototype::create(exec, this, NumberPrototype::createStructure(exec->globalData(), this, m_objectPrototype.get())));
232     m_numberObjectStructure.set(exec->globalData(), this, NumberObject::createStructure(exec->globalData(), this, m_numberPrototype.get()));
233
234     m_datePrototype.set(exec->globalData(), this, DatePrototype::create(exec, this, DatePrototype::createStructure(exec->globalData(), this, m_objectPrototype.get())));
235     m_dateStructure.set(exec->globalData(), this, DateInstance::createStructure(exec->globalData(), this, m_datePrototype.get()));
236
237     RegExp* emptyRegex = RegExp::create(exec->globalData(), "", NoFlags);
238     
239     m_regExpPrototype.set(exec->globalData(), this, RegExpPrototype::create(exec, this, RegExpPrototype::createStructure(exec->globalData(), this, m_objectPrototype.get()), emptyRegex));
240     m_regExpStructure.set(exec->globalData(), this, RegExpObject::createStructure(exec->globalData(), this, m_regExpPrototype.get()));
241
242     m_methodCallDummy.set(exec->globalData(), this, constructEmptyObject(exec));
243
244     ErrorPrototype* errorPrototype = ErrorPrototype::create(exec, this, ErrorPrototype::createStructure(exec->globalData(), this, m_objectPrototype.get()));
245     m_errorStructure.set(exec->globalData(), this, ErrorInstance::createStructure(exec->globalData(), this, errorPrototype));
246
247     // Constructors
248
249     JSCell* objectConstructor = ObjectConstructor::create(exec, this, ObjectConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_objectPrototype.get());
250     JSCell* functionConstructor = FunctionConstructor::create(exec, this, FunctionConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_functionPrototype.get());
251     JSCell* arrayConstructor = ArrayConstructor::create(exec, this, ArrayConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_arrayPrototype.get());
252     JSCell* stringConstructor = StringConstructor::create(exec, this, StringConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_stringPrototype.get());
253     JSCell* booleanConstructor = BooleanConstructor::create(exec, this, BooleanConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_booleanPrototype.get());
254     JSCell* numberConstructor = NumberConstructor::create(exec, this, NumberConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_numberPrototype.get());
255     JSCell* dateConstructor = DateConstructor::create(exec, this, DateConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_datePrototype.get());
256
257     m_regExpConstructor.set(exec->globalData(), this, RegExpConstructor::create(exec, this, RegExpConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), m_regExpPrototype.get()));
258
259     m_errorConstructor.set(exec->globalData(), this, ErrorConstructor::create(exec, this, ErrorConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get()), errorPrototype));
260
261     Structure* nativeErrorPrototypeStructure = NativeErrorPrototype::createStructure(exec->globalData(), this, errorPrototype);
262     Structure* nativeErrorStructure = NativeErrorConstructor::createStructure(exec->globalData(), this, m_functionPrototype.get());
263     m_evalErrorConstructor.set(exec->globalData(), this, NativeErrorConstructor::create(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "EvalError"));
264     m_rangeErrorConstructor.set(exec->globalData(), this, NativeErrorConstructor::create(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "RangeError"));
265     m_referenceErrorConstructor.set(exec->globalData(), this, NativeErrorConstructor::create(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "ReferenceError"));
266     m_syntaxErrorConstructor.set(exec->globalData(), this, NativeErrorConstructor::create(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "SyntaxError"));
267     m_typeErrorConstructor.set(exec->globalData(), this, NativeErrorConstructor::create(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "TypeError"));
268     m_URIErrorConstructor.set(exec->globalData(), this, NativeErrorConstructor::create(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "URIError"));
269
270     m_objectPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, objectConstructor, DontEnum);
271     m_functionPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, functionConstructor, DontEnum);
272     m_arrayPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, arrayConstructor, DontEnum);
273     m_booleanPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, booleanConstructor, DontEnum);
274     m_stringPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, stringConstructor, DontEnum);
275     m_numberPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, numberConstructor, DontEnum);
276     m_datePrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, dateConstructor, DontEnum);
277     m_regExpPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, m_regExpConstructor.get(), DontEnum);
278     errorPrototype->putDirectWithoutTransition(exec->globalData(), exec->propertyNames().constructor, m_errorConstructor.get(), DontEnum);
279
280     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "Object"), objectConstructor, DontEnum);
281     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "Function"), functionConstructor, DontEnum);
282     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "Array"), arrayConstructor, DontEnum);
283     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "Boolean"), booleanConstructor, DontEnum);
284     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "String"), stringConstructor, DontEnum);
285     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "Number"), numberConstructor, DontEnum);
286     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "Date"), dateConstructor, DontEnum);
287     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "RegExp"), m_regExpConstructor.get(), DontEnum);
288     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "Error"), m_errorConstructor.get(), DontEnum);
289     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "EvalError"), m_evalErrorConstructor.get(), DontEnum);
290     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "RangeError"), m_rangeErrorConstructor.get(), DontEnum);
291     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "ReferenceError"), m_referenceErrorConstructor.get(), DontEnum);
292     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "SyntaxError"), m_syntaxErrorConstructor.get(), DontEnum);
293     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "TypeError"), m_typeErrorConstructor.get(), DontEnum);
294     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "URIError"), m_URIErrorConstructor.get(), DontEnum);
295
296     m_evalFunction.set(exec->globalData(), this, JSFunction::create(exec, this, 1, exec->propertyNames().eval.ustring(), globalFuncEval));
297     putDirectWithoutTransition(exec->globalData(), exec->propertyNames().eval, m_evalFunction.get(), DontEnum);
298
299     putDirectWithoutTransition(exec->globalData(), Identifier(exec, "JSON"), JSONObject::create(exec, this, JSONObject::createStructure(exec->globalData(), this, m_objectPrototype.get())), DontEnum);
300
301     GlobalPropertyInfo staticGlobals[] = {
302         GlobalPropertyInfo(Identifier(exec, "Math"), MathObject::create(exec, this, MathObject::createStructure(exec->globalData(), this, m_objectPrototype.get())), DontEnum | DontDelete),
303         GlobalPropertyInfo(Identifier(exec, "NaN"), jsNaN(), DontEnum | DontDelete | ReadOnly),
304         GlobalPropertyInfo(Identifier(exec, "Infinity"), jsNumber(std::numeric_limits<double>::infinity()), DontEnum | DontDelete | ReadOnly),
305         GlobalPropertyInfo(Identifier(exec, "undefined"), jsUndefined(), DontEnum | DontDelete | ReadOnly)
306     };
307     addStaticGlobals(staticGlobals, WTF_ARRAY_LENGTH(staticGlobals));
308
309     resetPrototype(exec->globalData(), prototype);
310 }
311
312 void JSGlobalObject::createThrowTypeError(ExecState* exec)
313 {
314     JSFunction* thrower = JSFunction::create(exec, this, 0, "", globalFuncThrowTypeError);
315     GetterSetter* getterSetter = GetterSetter::create(exec);
316     getterSetter->setGetter(exec->globalData(), thrower);
317     getterSetter->setSetter(exec->globalData(), thrower);
318     m_throwTypeErrorGetterSetter.set(exec->globalData(), this, getterSetter);
319 }
320
321 // Set prototype, and also insert the object prototype at the end of the chain.
322 void JSGlobalObject::resetPrototype(JSGlobalData& globalData, JSValue prototype)
323 {
324     setPrototype(globalData, prototype);
325
326     JSObject* oldLastInPrototypeChain = lastInPrototypeChain(this);
327     JSObject* objectPrototype = m_objectPrototype.get();
328     if (oldLastInPrototypeChain != objectPrototype)
329         oldLastInPrototypeChain->setPrototype(globalData, objectPrototype);
330 }
331
332 void JSGlobalObject::visitChildren(JSCell* cell, SlotVisitor& visitor)
333
334     JSGlobalObject* thisObject = jsCast<JSGlobalObject*>(cell);
335     ASSERT_GC_OBJECT_INHERITS(thisObject, &s_info);
336     COMPILE_ASSERT(StructureFlags & OverridesVisitChildren, OverridesVisitChildrenWithoutSettingFlag);
337     ASSERT(thisObject->structure()->typeInfo().overridesVisitChildren());
338     JSVariableObject::visitChildren(thisObject, visitor);
339
340     visitIfNeeded(visitor, &thisObject->m_globalScopeChain);
341     visitIfNeeded(visitor, &thisObject->m_methodCallDummy);
342
343     visitIfNeeded(visitor, &thisObject->m_regExpConstructor);
344     visitIfNeeded(visitor, &thisObject->m_errorConstructor);
345     visitIfNeeded(visitor, &thisObject->m_evalErrorConstructor);
346     visitIfNeeded(visitor, &thisObject->m_rangeErrorConstructor);
347     visitIfNeeded(visitor, &thisObject->m_referenceErrorConstructor);
348     visitIfNeeded(visitor, &thisObject->m_syntaxErrorConstructor);
349     visitIfNeeded(visitor, &thisObject->m_typeErrorConstructor);
350     visitIfNeeded(visitor, &thisObject->m_URIErrorConstructor);
351
352     visitIfNeeded(visitor, &thisObject->m_evalFunction);
353     visitIfNeeded(visitor, &thisObject->m_callFunction);
354     visitIfNeeded(visitor, &thisObject->m_applyFunction);
355     visitIfNeeded(visitor, &thisObject->m_throwTypeErrorGetterSetter);
356
357     visitIfNeeded(visitor, &thisObject->m_objectPrototype);
358     visitIfNeeded(visitor, &thisObject->m_functionPrototype);
359     visitIfNeeded(visitor, &thisObject->m_arrayPrototype);
360     visitIfNeeded(visitor, &thisObject->m_booleanPrototype);
361     visitIfNeeded(visitor, &thisObject->m_stringPrototype);
362     visitIfNeeded(visitor, &thisObject->m_numberPrototype);
363     visitIfNeeded(visitor, &thisObject->m_datePrototype);
364     visitIfNeeded(visitor, &thisObject->m_regExpPrototype);
365
366     visitIfNeeded(visitor, &thisObject->m_argumentsStructure);
367     visitIfNeeded(visitor, &thisObject->m_arrayStructure);
368     visitIfNeeded(visitor, &thisObject->m_booleanObjectStructure);
369     visitIfNeeded(visitor, &thisObject->m_callbackConstructorStructure);
370     visitIfNeeded(visitor, &thisObject->m_callbackFunctionStructure);
371     visitIfNeeded(visitor, &thisObject->m_callbackObjectStructure);
372     visitIfNeeded(visitor, &thisObject->m_dateStructure);
373     visitIfNeeded(visitor, &thisObject->m_emptyObjectStructure);
374     visitIfNeeded(visitor, &thisObject->m_nullPrototypeObjectStructure);
375     visitIfNeeded(visitor, &thisObject->m_errorStructure);
376     visitIfNeeded(visitor, &thisObject->m_functionStructure);
377     visitIfNeeded(visitor, &thisObject->m_boundFunctionStructure);
378     visitIfNeeded(visitor, &thisObject->m_namedFunctionStructure);
379     visitIfNeeded(visitor, &thisObject->m_numberObjectStructure);
380     visitIfNeeded(visitor, &thisObject->m_regExpMatchesArrayStructure);
381     visitIfNeeded(visitor, &thisObject->m_regExpStructure);
382     visitIfNeeded(visitor, &thisObject->m_stringObjectStructure);
383     visitIfNeeded(visitor, &thisObject->m_internalFunctionStructure);
384
385     if (thisObject->m_registerArray) {
386         // Outside the execution of global code, when our variables are torn off,
387         // we can mark the torn-off array.
388         visitor.appendValues(thisObject->m_registerArray.get(), thisObject->m_registerArraySize);
389     } else if (thisObject->m_registers) {
390         // During execution of global code, when our variables are in the register file,
391         // the symbol table tells us how many variables there are, and registers
392         // points to where they end, and the registers used for execution begin.
393         visitor.appendValues(thisObject->m_registers - thisObject->symbolTable().size(), thisObject->symbolTable().size());
394     }
395 }
396
397 ExecState* JSGlobalObject::globalExec()
398 {
399     return CallFrame::create(m_globalCallFrame + RegisterFile::CallFrameHeaderSize);
400 }
401
402 void JSGlobalObject::resizeRegisters(size_t newSize)
403 {
404     // Previous duplicate symbols may have created spare capacity in m_registerArray.
405     if (newSize <= m_registerArraySize)
406         return;
407
408     size_t oldSize = m_registerArraySize;
409     OwnArrayPtr<WriteBarrier<Unknown> > registerArray = adoptArrayPtr(new WriteBarrier<Unknown>[newSize]);
410     for (size_t i = 0; i < oldSize; ++i)
411         registerArray[i].set(globalData(), this, m_registerArray[i].get());
412     for (size_t i = oldSize; i < newSize; ++i)
413         registerArray[i].setUndefined();
414
415     WriteBarrier<Unknown>* registers = registerArray.get();
416     setRegisters(registers, registerArray.release(), newSize);
417 }
418
419 void JSGlobalObject::addStaticGlobals(GlobalPropertyInfo* globals, int count)
420 {
421     resizeRegisters(symbolTable().size() + count);
422
423     for (int i = 0; i < count; ++i) {
424         GlobalPropertyInfo& global = globals[i];
425         ASSERT(global.attributes & DontDelete);
426         
427         int index = symbolTable().size();
428         SymbolTableEntry newEntry(index, global.attributes);
429         symbolTable().add(global.identifier.impl(), newEntry);
430         registerAt(index).set(globalData(), this, global.value);
431     }
432 }
433
434 bool JSGlobalObject::getOwnPropertySlot(JSCell* cell, ExecState* exec, PropertyName propertyName, PropertySlot& slot)
435 {
436     JSGlobalObject* thisObject = jsCast<JSGlobalObject*>(cell);
437     if (getStaticFunctionSlot<JSVariableObject>(exec, ExecState::globalObjectTable(exec), thisObject, propertyName, slot))
438         return true;
439     return thisObject->symbolTableGet(propertyName, slot);
440 }
441
442 bool JSGlobalObject::getOwnPropertyDescriptor(JSObject* object, ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor)
443 {
444     JSGlobalObject* thisObject = jsCast<JSGlobalObject*>(object);
445     if (getStaticFunctionDescriptor<JSVariableObject>(exec, ExecState::globalObjectTable(exec), thisObject, propertyName, descriptor))
446         return true;
447     return thisObject->symbolTableGet(propertyName, descriptor);
448 }
449
450 void JSGlobalObject::clearRareData(JSCell* cell)
451 {
452     jsCast<JSGlobalObject*>(cell)->m_rareData.clear();
453 }
454
455 DynamicGlobalObjectScope::DynamicGlobalObjectScope(JSGlobalData& globalData, JSGlobalObject* dynamicGlobalObject)
456     : m_dynamicGlobalObjectSlot(globalData.dynamicGlobalObject)
457     , m_savedDynamicGlobalObject(m_dynamicGlobalObjectSlot)
458 {
459     if (!m_dynamicGlobalObjectSlot) {
460 #if ENABLE(ASSEMBLER)
461         if (ExecutableAllocator::underMemoryPressure())
462             globalData.heap.discardAllCompiledCode();
463 #endif
464
465         m_dynamicGlobalObjectSlot = dynamicGlobalObject;
466
467         // Reset the date cache between JS invocations to force the VM
468         // to observe time zone changes.
469         globalData.resetDateCache();
470     }
471 }
472
473 void slowValidateCell(JSGlobalObject* globalObject)
474 {
475     if (!globalObject->isGlobalObject())
476         CRASH();
477     ASSERT_GC_OBJECT_INHERITS(globalObject, &JSGlobalObject::s_info);
478 }
479
480 } // namespace JSC