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 "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 "Lookup.h"
  55 #include "MathObject.h"
  56 #include "NativeErrorConstructor.h"
  57 #include "NativeErrorPrototype.h"
  58 #include "NumberConstructor.h"
  59 #include "NumberPrototype.h"
  60 #include "ObjectConstructor.h"
  61 #include "ObjectPrototype.h"
  62 #include "Profiler.h"
  63 #include "RegExpConstructor.h"
  64 #include "RegExpMatchesArray.h"
  65 #include "RegExpObject.h"
  66 #include "RegExpPrototype.h"
  67 #include "ScopeChainMark.h"
  68 #include "StringConstructor.h"
  69 #include "StringPrototype.h"
  70 #include "Debugger.h"
  71
  72 #include "JSGlobalObject.lut.h"
  73
  74 namespace JSC {
  75
  76 const ClassInfo JSGlobalObject::s_info = { "GlobalObject", &JSVariableObject::s_info, 0, ExecState::globalObjectTable };
  77
  78 /* Source for JSGlobalObject.lut.h
  79 @begin globalObjectTable
  80   parseInt              globalFuncParseInt              DontEnum|Function 2
  81   parseFloat            globalFuncParseFloat            DontEnum|Function 1
  82   isNaN                 globalFuncIsNaN                 DontEnum|Function 1
  83   isFinite              globalFuncIsFinite              DontEnum|Function 1
  84   escape                globalFuncEscape                DontEnum|Function 1
  85   unescape              globalFuncUnescape              DontEnum|Function 1
  86   decodeURI             globalFuncDecodeURI             DontEnum|Function 1
  87   decodeURIComponent    globalFuncDecodeURIComponent    DontEnum|Function 1
  88   encodeURI             globalFuncEncodeURI             DontEnum|Function 1
  89   encodeURIComponent    globalFuncEncodeURIComponent    DontEnum|Function 1
  90 @end
  91 */
  92
  93 ASSERT_CLASS_FITS_IN_CELL(JSGlobalObject);
  94
  95 // Default number of ticks before a timeout check should be done.
  96 static const int initialTickCountThreshold = 255;
  97
  98 // Preferred number of milliseconds between each timeout check
  99 static const int preferredScriptCheckTimeInterval = 1000;
 100
 101 template <typename T> static inline void visitIfNeeded(SlotVisitor& visitor, WriteBarrier<T>* v)
 102 {
 103     if (*v)
 104         visitor.append(v);
 105 }
 106
 107 JSGlobalObject::~JSGlobalObject()
 108 {
 109     ASSERT(JSLock::currentThreadIsHoldingLock());
 110
 111     if (m_debugger)
 112         m_debugger->detach(this);
 113
 114     Profiler** profiler = Profiler::enabledProfilerReference();
 115     if (UNLIKELY(*profiler != 0)) {
 116         (*profiler)->stopProfiling(this);
 117     }
 118 }
 119
 120 void JSGlobalObject::init(JSObject* thisValue)
 121 {
 122     ASSERT(JSLock::currentThreadIsHoldingLock());
 123
 124     structure()->disableSpecificFunctionTracking();
 125
 126     m_globalData = Heap::heap(this)->globalData();
 127     m_globalScopeChain.set(*m_globalData, this, new (m_globalData.get()) ScopeChainNode(0, this, m_globalData.get(), this, thisValue));
 128
 129     JSGlobalObject::globalExec()->init(0, 0, m_globalScopeChain.get(), CallFrame::noCaller(), 0, 0);
 130
 131     m_debugger = 0;
 132
 133     m_profileGroup = 0;
 134
 135     reset(prototype());
 136 }
 137
 138 void JSGlobalObject::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
 139 {
 140     ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));
 141
 142     if (symbolTablePut(exec->globalData(), propertyName, value))
 143         return;
 144     JSVariableObject::put(exec, propertyName, value, slot);
 145 }
 146
 147 void JSGlobalObject::putWithAttributes(ExecState* exec, const Identifier& propertyName, JSValue value, unsigned attributes)
 148 {
 149     ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));
 150
 151     if (symbolTablePutWithAttributes(exec->globalData(), propertyName, value, attributes))
 152         return;
 153
 154     JSValue valueBefore = getDirect(exec->globalData(), propertyName);
 155     PutPropertySlot slot;
 156     JSVariableObject::put(exec, propertyName, value, slot);
 157     if (!valueBefore) {
 158         JSValue valueAfter = getDirect(exec->globalData(), propertyName);
 159         if (valueAfter)
 160             JSObject::putWithAttributes(exec, propertyName, valueAfter, attributes);
 161     }
 162 }
 163
 164 void JSGlobalObject::defineGetter(ExecState* exec, const Identifier& propertyName, JSObject* getterFunc, unsigned attributes)
 165 {
 166     PropertySlot slot;
 167     if (!symbolTableGet(propertyName, slot))
 168         JSVariableObject::defineGetter(exec, propertyName, getterFunc, attributes);
 169 }
 170
 171 void JSGlobalObject::defineSetter(ExecState* exec, const Identifier& propertyName, JSObject* setterFunc, unsigned attributes)
 172 {
 173     PropertySlot slot;
 174     if (!symbolTableGet(propertyName, slot))
 175         JSVariableObject::defineSetter(exec, propertyName, setterFunc, attributes);
 176 }
 177
 178 static inline JSObject* lastInPrototypeChain(JSObject* object)
 179 {
 180     JSObject* o = object;
 181     while (o->prototype().isObject())
 182         o = asObject(o->prototype());
 183     return o;
 184 }
 185
 186 void JSGlobalObject::reset(JSValue prototype)
 187 {
 188     ExecState* exec = JSGlobalObject::globalExec();
 189
 190     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.
 191     m_functionStructure.set(exec->globalData(), this, JSFunction::createStructure(exec->globalData(), m_functionPrototype.get()));
 192     m_internalFunctionStructure.set(exec->globalData(), this, InternalFunction::createStructure(exec->globalData(), m_functionPrototype.get()));
 193     JSFunction* callFunction = 0;
 194     JSFunction* applyFunction = 0;
 195     m_functionPrototype->addFunctionProperties(exec, this, m_functionStructure.get(), &callFunction, &applyFunction);
 196     m_callFunction.set(exec->globalData(), this, callFunction);
 197     m_applyFunction.set(exec->globalData(), this, applyFunction);
 198     m_objectPrototype.set(exec->globalData(), this, new (exec) ObjectPrototype(exec, this, ObjectPrototype::createStructure(exec->globalData(), jsNull())));
 199     m_functionPrototype->structure()->setPrototypeWithoutTransition(exec->globalData(), m_objectPrototype.get());
 200
 201     m_emptyObjectStructure.set(exec->globalData(), this, m_objectPrototype->inheritorID(exec->globalData()));
 202     m_nullPrototypeObjectStructure.set(exec->globalData(), this, createEmptyObjectStructure(exec->globalData(), jsNull()));
 203
 204     m_callbackFunctionStructure.set(exec->globalData(), this, JSCallbackFunction::createStructure(exec->globalData(), m_functionPrototype.get()));
 205     m_argumentsStructure.set(exec->globalData(), this, Arguments::createStructure(exec->globalData(), m_objectPrototype.get()));
 206     m_callbackConstructorStructure.set(exec->globalData(), this, JSCallbackConstructor::createStructure(exec->globalData(), m_objectPrototype.get()));
 207     m_callbackObjectStructure.set(exec->globalData(), this, JSCallbackObject<JSObjectWithGlobalObject>::createStructure(exec->globalData(), m_objectPrototype.get()));
 208
 209     m_arrayPrototype.set(exec->globalData(), this, new (exec) ArrayPrototype(this, ArrayPrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
 210     m_arrayStructure.set(exec->globalData(), this, JSArray::createStructure(exec->globalData(), m_arrayPrototype.get()));
 211     m_regExpMatchesArrayStructure.set(exec->globalData(), this, RegExpMatchesArray::createStructure(exec->globalData(), m_arrayPrototype.get()));
 212
 213     m_stringPrototype.set(exec->globalData(), this, new (exec) StringPrototype(exec, this, StringPrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
 214     m_stringObjectStructure.set(exec->globalData(), this, StringObject::createStructure(exec->globalData(), m_stringPrototype.get()));
 215
 216     m_booleanPrototype.set(exec->globalData(), this, new (exec) BooleanPrototype(exec, this, BooleanPrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
 217     m_booleanObjectStructure.set(exec->globalData(), this, BooleanObject::createStructure(exec->globalData(), m_booleanPrototype.get()));
 218
 219     m_numberPrototype.set(exec->globalData(), this, new (exec) NumberPrototype(exec, this, NumberPrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
 220     m_numberObjectStructure.set(exec->globalData(), this, NumberObject::createStructure(exec->globalData(), m_numberPrototype.get()));
 221
 222     m_datePrototype.set(exec->globalData(), this, new (exec) DatePrototype(exec, this, DatePrototype::createStructure(exec->globalData(), m_objectPrototype.get())));
 223     m_dateStructure.set(exec->globalData(), this, DateInstance::createStructure(exec->globalData(), m_datePrototype.get()));
 224
 225     RegExp* emptyRegex = RegExp::create(&exec->globalData(), "", NoFlags);
 226
 227     m_regExpPrototype.set(exec->globalData(), this, new (exec) RegExpPrototype(exec, this, RegExpPrototype::createStructure(exec->globalData(), m_objectPrototype.get()), emptyRegex));
 228     m_regExpStructure.set(exec->globalData(), this, RegExpObject::createStructure(exec->globalData(), m_regExpPrototype.get()));
 229
 230     m_methodCallDummy.set(exec->globalData(), this, constructEmptyObject(exec));
 231
 232     ErrorPrototype* errorPrototype = new (exec) ErrorPrototype(exec, this, ErrorPrototype::createStructure(exec->globalData(), m_objectPrototype.get()));
 233     m_errorStructure.set(exec->globalData(), this, ErrorInstance::createStructure(exec->globalData(), errorPrototype));
 234
 235     // Constructors
 236
 237     JSCell* objectConstructor = new (exec) ObjectConstructor(exec, this, ObjectConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_objectPrototype.get());
 238     JSCell* functionConstructor = new (exec) FunctionConstructor(exec, this, FunctionConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_functionPrototype.get());
 239     JSCell* arrayConstructor = new (exec) ArrayConstructor(exec, this, ArrayConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_arrayPrototype.get());
 240     JSCell* stringConstructor = new (exec) StringConstructor(exec, this, StringConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_stringPrototype.get());
 241     JSCell* booleanConstructor = new (exec) BooleanConstructor(exec, this, BooleanConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_booleanPrototype.get());
 242     JSCell* numberConstructor = new (exec) NumberConstructor(exec, this, NumberConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_numberPrototype.get());
 243     JSCell* dateConstructor = new (exec) DateConstructor(exec, this, DateConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_datePrototype.get());
 244
 245     m_regExpConstructor.set(exec->globalData(), this, new (exec) RegExpConstructor(exec, this, RegExpConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), m_regExpPrototype.get()));
 246
 247     m_errorConstructor.set(exec->globalData(), this, new (exec) ErrorConstructor(exec, this, ErrorConstructor::createStructure(exec->globalData(), m_functionPrototype.get()), errorPrototype));
 248
 249     Structure* nativeErrorPrototypeStructure = NativeErrorPrototype::createStructure(exec->globalData(), errorPrototype);
 250     Structure* nativeErrorStructure = NativeErrorConstructor::createStructure(exec->globalData(), m_functionPrototype.get());
 251     m_evalErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "EvalError"));
 252     m_rangeErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "RangeError"));
 253     m_referenceErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "ReferenceError"));
 254     m_syntaxErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "SyntaxError"));
 255     m_typeErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "TypeError"));
 256     m_URIErrorConstructor.set(exec->globalData(), this, new (exec) NativeErrorConstructor(exec, this, nativeErrorStructure, nativeErrorPrototypeStructure, "URIError"));
 257
 258     m_objectPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, objectConstructor, DontEnum);
 259     m_functionPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, functionConstructor, DontEnum);
 260     m_arrayPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, arrayConstructor, DontEnum);
 261     m_booleanPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, booleanConstructor, DontEnum);
 262     m_stringPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, stringConstructor, DontEnum);
 263     m_numberPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, numberConstructor, DontEnum);
 264     m_datePrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, dateConstructor, DontEnum);
 265     m_regExpPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, m_regExpConstructor.get(), DontEnum);
 266     errorPrototype->putDirectFunctionWithoutTransition(exec->globalData(), exec->propertyNames().constructor, m_errorConstructor.get(), DontEnum);
 267
 268     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Object"), objectConstructor, DontEnum);
 269     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Function"), functionConstructor, DontEnum);
 270     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Array"), arrayConstructor, DontEnum);
 271     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Boolean"), booleanConstructor, DontEnum);
 272     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "String"), stringConstructor, DontEnum);
 273     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Number"), numberConstructor, DontEnum);
 274     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Date"), dateConstructor, DontEnum);
 275     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "RegExp"), m_regExpConstructor.get(), DontEnum);
 276     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "Error"), m_errorConstructor.get(), DontEnum);
 277     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "EvalError"), m_evalErrorConstructor.get(), DontEnum);
 278     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "RangeError"), m_rangeErrorConstructor.get(), DontEnum);
 279     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "ReferenceError"), m_referenceErrorConstructor.get(), DontEnum);
 280     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "SyntaxError"), m_syntaxErrorConstructor.get(), DontEnum);
 281     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "TypeError"), m_typeErrorConstructor.get(), DontEnum);
 282     putDirectFunctionWithoutTransition(exec->globalData(), Identifier(exec, "URIError"), m_URIErrorConstructor.get(), DontEnum);
 283
 284     m_evalFunction.set(exec->globalData(), this, new (exec) JSFunction(exec, this, m_functionStructure.get(), 1, exec->propertyNames().eval, globalFuncEval));
 285     putDirectFunctionWithoutTransition(exec, m_evalFunction.get(), DontEnum);
 286
 287     GlobalPropertyInfo staticGlobals[] = {
 288         GlobalPropertyInfo(Identifier(exec, "Math"), new (exec) MathObject(exec, this, MathObject::createStructure(exec->globalData(), m_objectPrototype.get())), DontEnum | DontDelete),
 289         GlobalPropertyInfo(Identifier(exec, "NaN"), jsNaN(), DontEnum | DontDelete | ReadOnly),
 290         GlobalPropertyInfo(Identifier(exec, "Infinity"), jsNumber(Inf), DontEnum | DontDelete | ReadOnly),
 291         GlobalPropertyInfo(Identifier(exec, "undefined"), jsUndefined(), DontEnum | DontDelete | ReadOnly),
 292         GlobalPropertyInfo(Identifier(exec, "JSON"), new (exec) JSONObject(this, JSONObject::createStructure(exec->globalData(), m_objectPrototype.get())), DontEnum | DontDelete)
 293     };
 294     addStaticGlobals(staticGlobals, WTF_ARRAY_LENGTH(staticGlobals));
 295
 296     resetPrototype(exec->globalData(), prototype);
 297 }
 298
 299 // Set prototype, and also insert the object prototype at the end of the chain.
 300 void 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
 310 void JSGlobalObject::visitChildren(SlotVisitor& visitor)
 311 {
 312     ASSERT_GC_OBJECT_INHERITS(this, &s_info);
 313     COMPILE_ASSERT(StructureFlags & OverridesVisitChildren, OverridesVisitChildrenWithoutSettingFlag);
 314     ASSERT(structure()->typeInfo().overridesVisitChildren());
 315     JSVariableObject::visitChildren(visitor);
 316
 317     visitIfNeeded(visitor, &m_globalScopeChain);
 318     visitIfNeeded(visitor, &m_methodCallDummy);
 319
 320     visitIfNeeded(visitor, &m_regExpConstructor);
 321     visitIfNeeded(visitor, &m_errorConstructor);
 322     visitIfNeeded(visitor, &m_evalErrorConstructor);
 323     visitIfNeeded(visitor, &m_rangeErrorConstructor);
 324     visitIfNeeded(visitor, &m_referenceErrorConstructor);
 325     visitIfNeeded(visitor, &m_syntaxErrorConstructor);
 326     visitIfNeeded(visitor, &m_typeErrorConstructor);
 327     visitIfNeeded(visitor, &m_URIErrorConstructor);
 328
 329     visitIfNeeded(visitor, &m_evalFunction);
 330     visitIfNeeded(visitor, &m_callFunction);
 331     visitIfNeeded(visitor, &m_applyFunction);
 332
 333     visitIfNeeded(visitor, &m_objectPrototype);
 334     visitIfNeeded(visitor, &m_functionPrototype);
 335     visitIfNeeded(visitor, &m_arrayPrototype);
 336     visitIfNeeded(visitor, &m_booleanPrototype);
 337     visitIfNeeded(visitor, &m_stringPrototype);
 338     visitIfNeeded(visitor, &m_numberPrototype);
 339     visitIfNeeded(visitor, &m_datePrototype);
 340     visitIfNeeded(visitor, &m_regExpPrototype);
 341
 342     visitIfNeeded(visitor, &m_argumentsStructure);
 343     visitIfNeeded(visitor, &m_arrayStructure);
 344     visitIfNeeded(visitor, &m_booleanObjectStructure);
 345     visitIfNeeded(visitor, &m_callbackConstructorStructure);
 346     visitIfNeeded(visitor, &m_callbackFunctionStructure);
 347     visitIfNeeded(visitor, &m_callbackObjectStructure);
 348     visitIfNeeded(visitor, &m_dateStructure);
 349     visitIfNeeded(visitor, &m_emptyObjectStructure);
 350     visitIfNeeded(visitor, &m_nullPrototypeObjectStructure);
 351     visitIfNeeded(visitor, &m_errorStructure);
 352     visitIfNeeded(visitor, &m_functionStructure);
 353     visitIfNeeded(visitor, &m_numberObjectStructure);
 354     visitIfNeeded(visitor, &m_regExpMatchesArrayStructure);
 355     visitIfNeeded(visitor, &m_regExpStructure);
 356     visitIfNeeded(visitor, &m_stringObjectStructure);
 357     visitIfNeeded(visitor, &m_internalFunctionStructure);
 358
 359     if (m_registerArray) {
 360         // Outside the execution of global code, when our variables are torn off,
 361         // we can mark the torn-off array.
 362         visitor.appendValues(m_registerArray.get(), m_registerArraySize);
 363     } else if (m_registers) {
 364         // During execution of global code, when our variables are in the register file,
 365         // the symbol table tells us how many variables there are, and registers
 366         // points to where they end, and the registers used for execution begin.
 367         visitor.appendValues(m_registers - symbolTable().size(), symbolTable().size());
 368     }
 369 }
 370
 371 ExecState* JSGlobalObject::globalExec()
 372 {
 373     return CallFrame::create(m_globalCallFrame + RegisterFile::CallFrameHeaderSize);
 374 }
 375
 376 bool JSGlobalObject::isDynamicScope(bool&) const
 377 {
 378     return true;
 379 }
 380
 381 void JSGlobalObject::disableEval()
 382 {
 383     ASSERT(m_isEvalEnabled);
 384     m_isEvalEnabled = false;
 385 }
 386
 387 void JSGlobalObject::copyGlobalsFrom(RegisterFile& registerFile)
 388 {
 389     ASSERT(!m_registerArray);
 390     ASSERT(!m_registerArraySize);
 391
 392     int numGlobals = registerFile.numGlobals();
 393     if (!numGlobals) {
 394         m_registers = 0;
 395         return;
 396     }
 397
 398     OwnArrayPtr<WriteBarrier<Unknown> > registerArray = copyRegisterArray(globalData(), reinterpret_cast<WriteBarrier<Unknown>*>(registerFile.lastGlobal()), numGlobals, numGlobals);
 399     WriteBarrier<Unknown>* registers = registerArray.get() + numGlobals;
 400     setRegisters(registers, registerArray.release(), numGlobals);
 401 }
 402
 403 void JSGlobalObject::copyGlobalsTo(RegisterFile& registerFile)
 404 {
 405     JSGlobalObject* lastGlobalObject = registerFile.globalObject();
 406     if (lastGlobalObject && lastGlobalObject != this)
 407         lastGlobalObject->copyGlobalsFrom(registerFile);
 408
 409     registerFile.setGlobalObject(this);
 410     registerFile.setNumGlobals(symbolTable().size());
 411
 412     if (m_registerArray) {
 413         // The register file is always a gc root so no barrier is needed here
 414         memcpy(registerFile.start() - m_registerArraySize, m_registerArray.get(), m_registerArraySize * sizeof(WriteBarrier<Unknown>));
 415         setRegisters(reinterpret_cast<WriteBarrier<Unknown>*>(registerFile.start()), nullptr, 0);
 416     }
 417 }
 418
 419 void JSGlobalObject::resizeRegisters(int oldSize, int newSize)
 420 {
 421     ASSERT(oldSize <= newSize);
 422     if (newSize == oldSize)
 423         return;
 424     ASSERT(newSize && newSize > oldSize);
 425     if (m_registerArray || !m_registers) {
 426         ASSERT(static_cast<size_t>(oldSize) == m_registerArraySize);
 427         OwnArrayPtr<WriteBarrier<Unknown> > registerArray = adoptArrayPtr(new WriteBarrier<Unknown>[newSize]);
 428         for (int i = 0; i < oldSize; i++)
 429             registerArray[newSize - oldSize + i].set(globalData(), this, m_registerArray[i].get());
 430         WriteBarrier<Unknown>* registers = registerArray.get() + newSize;
 431         setRegisters(registers, registerArray.release(), newSize);
 432     } else {
 433         ASSERT(static_cast<size_t>(newSize) < globalData().interpreter->registerFile().maxGlobals());
 434         globalData().interpreter->registerFile().setNumGlobals(newSize);
 435     }
 436
 437     for (int i = -newSize; i < -oldSize; ++i)
 438         m_registers[i].setUndefined();
 439 }
 440
 441 void* JSGlobalObject::operator new(size_t size, JSGlobalData* globalData)
 442 {
 443     return globalData->heap.allocate(size);
 444 }
 445
 446 void JSGlobalObject::addStaticGlobals(GlobalPropertyInfo* globals, int count)
 447 {
 448     size_t oldSize = m_registerArraySize;
 449     size_t newSize = oldSize + count;
 450     OwnArrayPtr<WriteBarrier<Unknown> > registerArray = adoptArrayPtr(new WriteBarrier<Unknown>[newSize]);
 451     if (m_registerArray) {
 452         // memcpy is safe here as we're copying barriers we already own from the existing array
 453         memcpy(registerArray.get() + count, m_registerArray.get(), oldSize * sizeof(Register));
 454     }
 455
 456     WriteBarrier<Unknown>* registers = registerArray.get() + newSize;
 457     setRegisters(registers, registerArray.release(), newSize);
 458
 459     for (int i = 0, index = -static_cast<int>(oldSize) - 1; i < count; ++i, --index) {
 460         GlobalPropertyInfo& global = globals[i];
 461         ASSERT(global.attributes & DontDelete);
 462         SymbolTableEntry newEntry(index, global.attributes);
 463         symbolTable().add(global.identifier.impl(), newEntry);
 464         registerAt(index).set(globalData(), this, global.value);
 465     }
 466 }
 467
 468 bool JSGlobalObject::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
 469 {
 470     if (getStaticFunctionSlot<JSVariableObject>(exec, ExecState::globalObjectTable(exec), this, propertyName, slot))
 471         return true;
 472     return symbolTableGet(propertyName, slot);
 473 }
 474
 475 bool JSGlobalObject::getOwnPropertyDescriptor(ExecState* exec, const Identifier& propertyName, PropertyDescriptor& descriptor)
 476 {
 477     if (getStaticFunctionDescriptor<JSVariableObject>(exec, ExecState::globalObjectTable(exec), this, propertyName, descriptor))
 478         return true;
 479     return symbolTableGet(propertyName, descriptor);
 480 }
 481
 482 void JSGlobalObject::WeakMapsFinalizer::finalize(Handle<Unknown> handle, void*)
 483 {
 484     JSGlobalObject* globalObject = asGlobalObject(handle.get());
 485     globalObject->m_weakMaps.clear();
 486 }
 487
 488 JSGlobalObject::WeakMapsFinalizer* JSGlobalObject::weakMapsFinalizer()
 489 {
 490     static WeakMapsFinalizer* finalizer = new WeakMapsFinalizer();
 491     return finalizer;
 492 }
 493
 494 DynamicGlobalObjectScope::DynamicGlobalObjectScope(JSGlobalData& globalData, JSGlobalObject* dynamicGlobalObject)
 495     : m_dynamicGlobalObjectSlot(globalData.dynamicGlobalObject)
 496     , m_savedDynamicGlobalObject(m_dynamicGlobalObjectSlot)
 497 {
 498     if (!m_dynamicGlobalObjectSlot) {
 499 #if ENABLE(ASSEMBLER)
 500         if (ExecutableAllocator::underMemoryPressure())
 501             globalData.recompileAllJSFunctions();
 502 #endif
 503
 504         m_dynamicGlobalObjectSlot = dynamicGlobalObject;
 505
 506         // Reset the date cache between JS invocations to force the VM
 507         // to observe time zone changes.
 508         globalData.resetDateCache();
 509     }
 510 }
 511
 512 void slowValidateCell(JSGlobalObject* globalObject)
 513 {
 514     if (!globalObject->isGlobalObject())
 515         CRASH();
 516     ASSERT_GC_OBJECT_INHERITS(globalObject, &JSGlobalObject::s_info);
 517 }
 518
 519 } // namespace JSC