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     , &shouldInterruptScriptBeforeTimeout
  83 };
  84
  85 /* Source for JSGlobalObject.lut.h
  86 @begin globalObjectTable
  87   parseInt              globalFuncParseInt              DontEnum|Function 2
  88   parseFloat            globalFuncParseFloat            DontEnum|Function 1
  89   isNaN                 globalFuncIsNaN                 DontEnum|Function 1
  90   isFinite              globalFuncIsFinite              DontEnum|Function 1
  91   escape                globalFuncEscape                DontEnum|Function 1
  92   unescape              globalFuncUnescape              DontEnum|Function 1
  93   decodeURI             globalFuncDecodeURI             DontEnum|Function 1
  94   decodeURIComponent    globalFuncDecodeURIComponent    DontEnum|Function 1
  95   encodeURI             globalFuncEncodeURI             DontEnum|Function 1
  96   encodeURIComponent    globalFuncEncodeURIComponent    DontEnum|Function 1
  97 @end
  98 */
  99
 100 ASSERT_CLASS_FITS_IN_CELL(JSGlobalObject);
 101
 102 // Default number of ticks before a timeout check should be done.
 103 static const int initialTickCountThreshold = 255;
 104
 105 // Preferred number of milliseconds between each timeout check
 106 static const int preferredScriptCheckTimeInterval = 1000;
 107
 108 template <typename T> static inline void visitIfNeeded(SlotVisitor& visitor, WriteBarrier<T>* v)
 109 {
 110     if (*v)
 111         visitor.append(v);
 112 }
 113
 114 JSGlobalObject::~JSGlobalObject()
 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(globalData().apiLock().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, const Identifier& 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, const Identifier& 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, const Identifier& 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, Identifier(), globalFuncProtoGetter));
 209     protoAccessor->setSetter(exec->globalData(), JSFunction::create(exec, this, 0, Identifier(), 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, 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, Identifier(), 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, const Identifier& 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, const Identifier& 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