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 "ErrorConstructor.h"
46#include "ErrorPrototype.h"
47#include "FunctionConstructor.h"
48#include "FunctionPrototype.h"
49#include "JSFunction.h"
50#include "JSGlobalObjectFunctions.h"
51#include "JSLock.h"
52#include "JSONObject.h"
53#include "Interpreter.h"
54#include "MathObject.h"
55#include "NativeErrorConstructor.h"
56#include "NativeErrorPrototype.h"
57#include "NumberConstructor.h"
58#include "NumberPrototype.h"
59#include "ObjectConstructor.h"
60#include "ObjectPrototype.h"
61#include "Profiler.h"
62#include "RegExpConstructor.h"
63#include "RegExpMatchesArray.h"
64#include "RegExpObject.h"
65#include "RegExpPrototype.h"
66#include "ScopeChainMark.h"
67#include "StringConstructor.h"
68#include "StringPrototype.h"
69#include "Debugger.h"
70
71namespace JSC {
72
73ASSERT_CLASS_FITS_IN_CELL(JSGlobalObject);
74
75// Default number of ticks before a timeout check should be done.
76static const int initialTickCountThreshold = 255;
77
78// Preferred number of milliseconds between each timeout check
79static const int preferredScriptCheckTimeInterval = 1000;
80
81template <typename T> static inline void markIfNeeded(MarkStack& markStack, WriteBarrier<T>* v)
82{
83    if (*v)
84        markStack.append(v);
85}
86
87JSGlobalObject::~JSGlobalObject()
88{
89    ASSERT(JSLock::currentThreadIsHoldingLock());
90
91    if (m_debugger)
92        m_debugger->detach(this);
93
94    Profiler** profiler = Profiler::enabledProfilerReference();
95    if (UNLIKELY(*profiler != 0)) {
96        (*profiler)->stopProfiling(this);
97    }
98}
99
100void JSGlobalObject::init(JSObject* thisValue)
101{
102    ASSERT(JSLock::currentThreadIsHoldingLock());
103
104    structure()->disableSpecificFunctionTracking();
105
106    m_globalData = Heap::heap(this)->globalData();
107    m_globalScopeChain.set(*m_globalData, this, new (m_globalData.get()) ScopeChainNode(0, this, m_globalData.get(), this, thisValue));
108
109    JSGlobalObject::globalExec()->init(0, 0, m_globalScopeChain.get(), CallFrame::noCaller(), 0, 0);
110
111    m_debugger = 0;
112
113    m_profileGroup = 0;
114
115    reset(prototype());
116}
117
118void JSGlobalObject::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
119{
120    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));
121
122    if (symbolTablePut(exec->globalData(), propertyName, value))
123        return;
124    JSVariableObject::put(exec, propertyName, value, slot);
125}
126
127void JSGlobalObject::putWithAttributes(ExecState* exec, const Identifier& propertyName, JSValue value, unsigned attributes)
128{
129    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));
130
131    if (symbolTablePutWithAttributes(exec->globalData(), propertyName, value, attributes))
132        return;
133
134    JSValue valueBefore = getDirect(exec->globalData(), propertyName);
135    PutPropertySlot slot;
136    JSVariableObject::put(exec, propertyName, value, slot);
137    if (!valueBefore) {
138        JSValue valueAfter = getDirect(exec->globalData(), propertyName);
139        if (valueAfter)
140            JSObject::putWithAttributes(exec, propertyName, valueAfter, attributes);
141    }
142}
143
144void JSGlobalObject::defineGetter(ExecState* exec, const Identifier& propertyName, JSObject* getterFunc, unsigned attributes)
145{
146    PropertySlot slot;
147    if (!symbolTableGet(propertyName, slot))
148        JSVariableObject::defineGetter(exec, propertyName, getterFunc, attributes);
149}
150
151void JSGlobalObject::defineSetter(ExecState* exec, const Identifier& propertyName, JSObject* setterFunc, unsigned attributes)
152{
153    PropertySlot slot;
154    if (!symbolTableGet(propertyName, slot))
155        JSVariableObject::defineSetter(exec, propertyName, setterFunc, attributes);
156}
157
158static inline JSObject* lastInPrototypeChain(JSObject* object)
159{
160    JSObject* o = object;
161    while (o->prototype().isObject())
162        o = asObject(o->prototype());
163    return o;
164}
165
166void JSGlobalObject::reset(JSValue prototype)
167{
168    ExecState* exec = JSGlobalObject::globalExec();
169
170    // Prototypes
171
172    m_functionPrototype.set(exec->globalData(), this, new (exec) FunctionPrototype(exec, this, FunctionPrototype::createStructure(exec->globalData(), jsNull()))); // The real prototype will be set once ObjectPrototype is created.
173    m_functionStructure.set(exec->globalData(), this, JSFunction::createStructure(exec->globalData(), m_functionPrototype.get()));
174    m_internalFunctionStructure.set(exec->globalData(), this, InternalFunction::createStructure(exec->globalData(), m_functionPrototype.get()));
175    JSFunction* callFunction = 0;
176    JSFunction* applyFunction = 0;
177    m_functionPrototype->addFunctionProperties(exec, this, m_functionStructure.get(), &callFunction, &applyFunction);
178    m_callFunction.set(exec->globalData(), this, callFunction);
179    m_applyFunction.set(exec->globalData(), this, applyFunction);
180    m_objectPrototype.set(exec->globalData(), this, new (exec) ObjectPrototype(exec, this, ObjectPrototype::createStructure(exec->globalData(), jsNull()), m_functionStructure.get()));
181    m_functionPrototype->structure()->setPrototypeWithoutTransition(exec->globalData(), m_objectPrototype.get());
182
183    m_emptyObjectStructure.set(exec->globalData(), this, m_objectPrototype->inheritorID(exec->globalData()));
184
185    m_callbackFunctionStructure.set(exec->globalData(), this, JSCallbackFunction::createStructure(exec->globalData(), m_functionPrototype.get()));
186    m_argumentsStructure.set(exec->globalData(), this, Arguments::createStructure(exec->globalData(), m_objectPrototype.get()));
187    m_callbackConstructorStructure.set(exec->globalData(), this, JSCallbackConstructor::createStructure(exec->globalData(), m_objectPrototype.get()));
188    m_callbackObjectStructure.set(exec->globalData(), this, JSCallbackObject<JSObjectWithGlobalObject>::createStructure(exec->globalData(), m_objectPrototype.get()));
189
190    m_arrayPrototype.set(exec->globalData(), this, new (exec) ArrayPrototype(this, ArrayPrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
191    m_arrayStructure.set(exec->globalData(), this, JSArray::createStructure(exec->globalData(), m_arrayPrototype.get()));
192    m_regExpMatchesArrayStructure.set(exec->globalData(), this, RegExpMatchesArray::createStructure(exec->globalData(), m_arrayPrototype.get()));
193
194    m_stringPrototype.set(exec->globalData(), this, new (exec) StringPrototype(exec, this, StringPrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
195    m_stringObjectStructure.set(exec->globalData(), this, StringObject::createStructure(exec->globalData(), m_stringPrototype.get()));
196
197    m_booleanPrototype.set(exec->globalData(), this, new (exec) BooleanPrototype(exec, this, BooleanPrototype::createStructure(exec->globalData(), m_objectPrototype.get()), m_functionStructure.get()));
198    m_booleanObjectStructure.set(exec->globalData(), this, BooleanObject::createStructure(exec->globalData(), m_booleanPrototype.get()));
199
200    m_numberPrototype.set(exec->globalData(), this, new (exec) NumberPrototype(exec, this, NumberPrototype::createStructure(exec->globalData(), m_objectPrototype.get()), m_functionStructure.get()));
201    m_numberObjectStructure.set(exec->globalData(), this, NumberObject::createStructure(exec->globalData(), m_numberPrototype.get()));
202
203    m_datePrototype.set(exec->globalData(), this, new (exec) DatePrototype(exec, this, DatePrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
204    m_dateStructure.set(exec->globalData(), this, DateInstance::createStructure(exec->globalData(), m_datePrototype.get()));
205
206    m_regExpPrototype.set(exec->globalData(), this, new (exec) RegExpPrototype(exec, this, RegExpPrototype::createStructure(exec->globalData(), m_objectPrototype.get()), m_functionStructure.get()));
207    m_regExpStructure.set(exec->globalData(), this, RegExpObject::createStructure(exec->globalData(), m_regExpPrototype.get()));
208
209    m_methodCallDummy.set(exec->globalData(), this, constructEmptyObject(exec));
210
211    ErrorPrototype* errorPrototype = new (exec) ErrorPrototype(exec, this, ErrorPrototype::createStructure(exec->globalData(), m_objectPrototype.get()), m_functionStructure.get());
212    m_errorStructure.set(exec->globalData(), this, ErrorInstance::createStructure(exec->globalData(), errorPrototype));
213
214    // Constructors
215
216    JSCell* objectConstructor = new (exec) ObjectConstructor(exec, this, ObjectConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_objectPrototype.get());
217    JSCell* functionConstructor = new (exec) FunctionConstructor(exec, this, FunctionConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_functionPrototype.get());
218    JSCell* arrayConstructor = new (exec) ArrayConstructor(exec, this, ArrayConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_arrayPrototype.get(), m_functionStructure.get());
219    JSCell* stringConstructor = new (exec) StringConstructor(exec, this, StringConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_functionStructure.get(), m_stringPrototype.get());
220    JSCell* booleanConstructor = new (exec) BooleanConstructor(exec, this, BooleanConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_booleanPrototype.get());
221    JSCell* numberConstructor = new (exec) NumberConstructor(exec, this, NumberConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_numberPrototype.get());
222    JSCell* dateConstructor = new (exec) DateConstructor(exec, this, DateConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_functionStructure.get(), m_datePrototype.get());
223
224    m_regExpConstructor.set(exec->globalData(), this, new (exec) RegExpConstructor(exec, this, RegExpConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_regExpPrototype.get()));
225
226    m_errorConstructor.set(exec->globalData(), this, new (exec) ErrorConstructor(exec, this, ErrorConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), errorPrototype));
227
228    Structure* nativeErrorPrototypeStructure = NativeErrorPrototype::createStructure(exec->globalData(), errorPrototype);
229    Structure* nativeErrorStructure = NativeErrorConstructor::createStructure(exec->globalData(), m_functionPrototype.get());
230    m_evalErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "EvalError"));
231    m_rangeErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "RangeError"));
232    m_referenceErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "ReferenceError"));
233    m_syntaxErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "SyntaxError"));
234    m_typeErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "TypeError"));
235    m_URIErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "URIError"));
236
237    m_objectPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, objectConstructor, DontEnum);
238    m_functionPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, functionConstructor, DontEnum);
239    m_arrayPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, arrayConstructor, DontEnum);
240    m_booleanPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, booleanConstructor, DontEnum);
241    m_stringPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, stringConstructor, DontEnum);
242    m_numberPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, numberConstructor, DontEnum);
243    m_datePrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, dateConstructor, DontEnum);
244    m_regExpPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, m_regExpConstructor.get(), DontEnum);
245    errorPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, m_errorConstructor.get(), DontEnum);
246
247    // Set global constructors
248
249    // FIXME: These properties could be handled by a static hash table.
250
251    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Object"), objectConstructor, DontEnum);
252    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Function"), functionConstructor, DontEnum);
253    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Array"), arrayConstructor, DontEnum);
254    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Boolean"), booleanConstructor, DontEnum);
255    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "String"), stringConstructor, DontEnum);
256    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Number"), numberConstructor, DontEnum);
257    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Date"), dateConstructor, DontEnum);
258    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "RegExp"), m_regExpConstructor.get(), DontEnum);
259    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Error"), m_errorConstructor.get(), DontEnum);
260    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "EvalError"), m_evalErrorConstructor.get(), DontEnum);
261    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "RangeError"), m_rangeErrorConstructor.get(), DontEnum);
262    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "ReferenceError"), m_referenceErrorConstructor.get(), DontEnum);
263    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "SyntaxError"), m_syntaxErrorConstructor.get(), DontEnum);
264    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "TypeError"), m_typeErrorConstructor.get(), DontEnum);
265    putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "URIError"), m_URIErrorConstructor.get(), DontEnum);
266
267    // Set global values.
268    GlobalPropertyInfo staticGlobals[] = {
269        GlobalPropertyInfo(Identifier(exec, "Math"), new (exec) MathObject(exec, this, MathObject::createStructure(exec->globalData(), m_objectPrototype.get())), DontEnum | DontDelete),
270        GlobalPropertyInfo(Identifier(exec, "NaN"), jsNaN(), DontEnum | DontDelete | ReadOnly),
271        GlobalPropertyInfo(Identifier(exec, "Infinity"), jsNumber(Inf), DontEnum | DontDelete | ReadOnly),
272        GlobalPropertyInfo(Identifier(exec, "undefined"), jsUndefined(), DontEnum | DontDelete | ReadOnly),
273        GlobalPropertyInfo(Identifier(exec, "JSON"), new (exec) JSONObject(this, JSONObject::createStructure(exec->globalData(), m_objectPrototype.get())), DontEnum | DontDelete)
274    };
275
276    addStaticGlobals(staticGlobals, WTF_ARRAY_LENGTH(staticGlobals));
277
278    // Set global functions.
279
280    m_evalFunction.set(exec->globalData(), this, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, exec->propertyNames().eval, globalFuncEval));
281    putDirectFunctionWithoutTransition(exec, m_evalFunction.get(), DontEnum);
282    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 2, Identifier(exec, "parseInt"), globalFuncParseInt), DontEnum);
283    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "parseFloat"), globalFuncParseFloat), DontEnum);
284    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "isNaN"), globalFuncIsNaN), DontEnum);
285    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "isFinite"), globalFuncIsFinite), DontEnum);
286    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "escape"), globalFuncEscape), DontEnum);
287    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "unescape"), globalFuncUnescape), DontEnum);
288    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "decodeURI"), globalFuncDecodeURI), DontEnum);
289    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "decodeURIComponent"), globalFuncDecodeURIComponent), DontEnum);
290    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "encodeURI"), globalFuncEncodeURI), DontEnum);
291    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "encodeURIComponent"), globalFuncEncodeURIComponent), DontEnum);
292#ifndef NDEBUG
293    putDirectFunctionWithoutTransition(exec, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, Identifier(exec, "jscprint"), globalFuncJSCPrint), DontEnum);
294#endif
295
296    resetPrototype(exec->globalData(), prototype);
297}
298
299// Set prototype, and also insert the object prototype at the end of the chain.
300void JSGlobalObject::resetPrototype(JSGlobalData& globalData, JSValue prototype)
301{
302    setPrototype(globalData, prototype);
303
304    JSObject* oldLastInPrototypeChain = lastInPrototypeChain(this);
305    JSObject* objectPrototype = m_objectPrototype.get();
306    if (oldLastInPrototypeChain != objectPrototype)
307        oldLastInPrototypeChain->setPrototype(globalData, objectPrototype);
308}
309
310void JSGlobalObject::markChildren(MarkStack& markStack)
311{
312    JSVariableObject::markChildren(markStack);
313
314    markIfNeeded(markStack, &m_globalScopeChain);
315    markIfNeeded(markStack, &m_methodCallDummy);
316
317    markIfNeeded(markStack, &m_regExpConstructor);
318    markIfNeeded(markStack, &m_errorConstructor);
319    markIfNeeded(markStack, &m_evalErrorConstructor);
320    markIfNeeded(markStack, &m_rangeErrorConstructor);
321    markIfNeeded(markStack, &m_referenceErrorConstructor);
322    markIfNeeded(markStack, &m_syntaxErrorConstructor);
323    markIfNeeded(markStack, &m_typeErrorConstructor);
324    markIfNeeded(markStack, &m_URIErrorConstructor);
325
326    markIfNeeded(markStack, &m_evalFunction);
327    markIfNeeded(markStack, &m_callFunction);
328    markIfNeeded(markStack, &m_applyFunction);
329
330    markIfNeeded(markStack, &m_objectPrototype);
331    markIfNeeded(markStack, &m_functionPrototype);
332    markIfNeeded(markStack, &m_arrayPrototype);
333    markIfNeeded(markStack, &m_booleanPrototype);
334    markIfNeeded(markStack, &m_stringPrototype);
335    markIfNeeded(markStack, &m_numberPrototype);
336    markIfNeeded(markStack, &m_datePrototype);
337    markIfNeeded(markStack, &m_regExpPrototype);
338
339    markIfNeeded(markStack, &m_argumentsStructure);
340    markIfNeeded(markStack, &m_arrayStructure);
341    markIfNeeded(markStack, &m_booleanObjectStructure);
342    markIfNeeded(markStack, &m_callbackConstructorStructure);
343    markIfNeeded(markStack, &m_callbackFunctionStructure);
344    markIfNeeded(markStack, &m_callbackObjectStructure);
345    markIfNeeded(markStack, &m_dateStructure);
346    markIfNeeded(markStack, &m_emptyObjectStructure);
347    markIfNeeded(markStack, &m_errorStructure);
348    markIfNeeded(markStack, &m_functionStructure);
349    markIfNeeded(markStack, &m_numberObjectStructure);
350    markIfNeeded(markStack, &m_regExpMatchesArrayStructure);
351    markIfNeeded(markStack, &m_regExpStructure);
352    markIfNeeded(markStack, &m_stringObjectStructure);
353    markIfNeeded(markStack, &m_internalFunctionStructure);
354
355    if (m_registerArray) {
356        // Outside the execution of global code, when our variables are torn off,
357        // we can mark the torn-off array.
358        markStack.appendValues(m_registerArray.get(), m_registerArraySize);
359    } else if (m_registers) {
360        // During execution of global code, when our variables are in the register file,
361        // the symbol table tells us how many variables there are, and registers
362        // points to where they end, and the registers used for execution begin.
363        markStack.appendValues(m_registers - symbolTable().size(), symbolTable().size());
364    }
365}
366
367ExecState* JSGlobalObject::globalExec()
368{
369    return CallFrame::create(m_globalCallFrame + RegisterFile::CallFrameHeaderSize);
370}
371
372bool JSGlobalObject::isDynamicScope(bool&) const
373{
374    return true;
375}
376
377void JSGlobalObject::copyGlobalsFrom(RegisterFile& registerFile)
378{
379    ASSERT(!m_registerArray);
380    ASSERT(!m_registerArraySize);
381
382    int numGlobals = registerFile.numGlobals();
383    if (!numGlobals) {
384        m_registers = 0;
385        return;
386    }
387
388    OwnArrayPtr<WriteBarrier<Unknown> > registerArray = copyRegisterArray(globalData(), reinterpret_cast<WriteBarrier<Unknown>*>(registerFile.lastGlobal()), numGlobals, numGlobals);
389    WriteBarrier<Unknown>* registers = registerArray.get() + numGlobals;
390    setRegisters(registers, registerArray.release(), numGlobals);
391}
392
393void JSGlobalObject::copyGlobalsTo(RegisterFile& registerFile)
394{
395    JSGlobalObject* lastGlobalObject = registerFile.globalObject();
396    if (lastGlobalObject && lastGlobalObject != this)
397        lastGlobalObject->copyGlobalsFrom(registerFile);
398
399    registerFile.setGlobalObject(this);
400    registerFile.setNumGlobals(symbolTable().size());
401
402    if (m_registerArray) {
403        // The register file is always a gc root so no barrier is needed here
404        memcpy(registerFile.start() - m_registerArraySize, m_registerArray.get(), m_registerArraySize * sizeof(WriteBarrier<Unknown>));
405        setRegisters(reinterpret_cast<WriteBarrier<Unknown>*>(registerFile.start()), nullptr, 0);
406    }
407}
408
409void JSGlobalObject::resizeRegisters(int oldSize, int newSize)
410{
411    ASSERT(oldSize <= newSize);
412    if (newSize == oldSize)
413        return;
414    ASSERT(newSize && newSize > oldSize);
415    if (m_registerArray || !m_registers) {
416        ASSERT(static_cast<size_t>(oldSize) == m_registerArraySize);
417        OwnArrayPtr<WriteBarrier<Unknown> > registerArray = adoptArrayPtr(new WriteBarrier<Unknown>[newSize]);
418        for (int i = 0; i < oldSize; i++)
419            registerArray[newSize - oldSize + i].set(globalData(), this, m_registerArray[i].get());
420        WriteBarrier<Unknown>* registers = registerArray.get() + newSize;
421        setRegisters(registers, registerArray.release(), newSize);
422    } else {
423        ASSERT(static_cast<size_t>(newSize) < globalData().interpreter->registerFile().maxGlobals());
424        globalData().interpreter->registerFile().setNumGlobals(newSize);
425    }
426
427    for (int i = -newSize; i < -oldSize; ++i)
428        m_registers[i].setUndefined();
429}
430
431void* JSGlobalObject::operator new(size_t size, JSGlobalData* globalData)
432{
433    return globalData->heap.allocate(size);
434}
435
436DynamicGlobalObjectScope::DynamicGlobalObjectScope(JSGlobalData& globalData, JSGlobalObject* dynamicGlobalObject)
437    : m_dynamicGlobalObjectSlot(globalData.dynamicGlobalObject)
438    , m_savedDynamicGlobalObject(m_dynamicGlobalObjectSlot)
439{
440    if (!m_dynamicGlobalObjectSlot) {
441#if ENABLE(ASSEMBLER)
442        if (ExecutableAllocator::underMemoryPressure())
443            globalData.recompileAllJSFunctions();
444#endif
445
446        m_dynamicGlobalObjectSlot = dynamicGlobalObject;
447
448        // Reset the date cache between JS invocations to force the VM
449        // to observe time zone changes.
450        globalData.resetDateCache();
451    }
452}
453
454} // namespace JSC
455