runtime/Arguments.cpp

   1 /*
   2  *  Copyright (C) 1999-2002 Harri Porten (porten@kde.org)
   3  *  Copyright (C) 2001 Peter Kelly (pmk@post.com)
   4  *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
   5  *  Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca)
   6  *  Copyright (C) 2007 Maks Orlovich
   7  *
   8  *  This library is free software; you can redistribute it and/or
   9  *  modify it under the terms of the GNU Library General Public
  10  *  License as published by the Free Software Foundation; either
  11  *  version 2 of the License, or (at your option) any later version.
  12  *
  13  *  This library is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *  Library General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU Library General Public License
  19  *  along with this library; see the file COPYING.LIB.  If not, write to
  20  *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  21  *  Boston, MA 02110-1301, USA.
  22  *
  23  */
  24
  25 #include "config.h"
  26 #include "Arguments.h"
  27
  28 #include "JSActivation.h"
  29 #include "JSFunction.h"
  30 #include "JSGlobalObject.h"
  31
  32 using namespace std;
  33
  34 namespace JSC {
  35
  36 ASSERT_CLASS_FITS_IN_CELL(Arguments);
  37
  38 const ClassInfo Arguments::info = { "Arguments", 0, 0, 0 };
  39
  40 Arguments::~Arguments()
  41 {
  42     if (d->extraArguments != d->extraArgumentsFixedBuffer)
  43         delete [] d->extraArguments;
  44 }
  45
  46 void Arguments::markChildren(MarkStack& markStack)
  47 {
  48     JSObject::markChildren(markStack);
  49
  50     if (d->registerArray)
  51         markStack.appendValues(reinterpret_cast<JSValue*>(d->registerArray.get()), d->numParameters);
  52
  53     if (d->extraArguments) {
  54         unsigned numExtraArguments = d->numArguments - d->numParameters;
  55         markStack.appendValues(reinterpret_cast<JSValue*>(d->extraArguments), numExtraArguments);
  56     }
  57
  58     markStack.append(d->callee);
  59
  60     if (d->activation)
  61         markStack.append(d->activation);
  62 }
  63
  64 void Arguments::copyToRegisters(ExecState* exec, Register* buffer, uint32_t maxSize)
  65 {
  66     if (UNLIKELY(d->overrodeLength)) {
  67         unsigned length = min(get(exec, exec->propertyNames().length).toUInt32(exec), maxSize);
  68         for (unsigned i = 0; i < length; i++)
  69             buffer[i] = get(exec, i);
  70         return;
  71     }
  72
  73     if (LIKELY(!d->deletedArguments)) {
  74         unsigned parametersLength = min(min(d->numParameters, d->numArguments), maxSize);
  75         unsigned i = 0;
  76         for (; i < parametersLength; ++i)
  77             buffer[i] = d->registers[d->firstParameterIndex + i].jsValue();
  78         for (; i < d->numArguments; ++i)
  79             buffer[i] = d->extraArguments[i - d->numParameters].jsValue();
  80         return;
  81     }
  82
  83     unsigned parametersLength = min(min(d->numParameters, d->numArguments), maxSize);
  84     unsigned i = 0;
  85     for (; i < parametersLength; ++i) {
  86         if (!d->deletedArguments[i])
  87             buffer[i] = d->registers[d->firstParameterIndex + i].jsValue();
  88         else
  89             buffer[i] = get(exec, i);
  90     }
  91     for (; i < d->numArguments; ++i) {
  92         if (!d->deletedArguments[i])
  93             buffer[i] = d->extraArguments[i - d->numParameters].jsValue();
  94         else
  95             buffer[i] = get(exec, i);
  96     }
  97 }
  98
  99 void Arguments::fillArgList(ExecState* exec, MarkedArgumentBuffer& args)
 100 {
 101     if (UNLIKELY(d->overrodeLength)) {
 102         unsigned length = get(exec, exec->propertyNames().length).toUInt32(exec);
 103         for (unsigned i = 0; i < length; i++)
 104             args.append(get(exec, i));
 105         return;
 106     }
 107
 108     if (LIKELY(!d->deletedArguments)) {
 109         if (LIKELY(!d->numParameters)) {
 110             args.initialize(d->extraArguments, d->numArguments);
 111             return;
 112         }
 113
 114         if (d->numParameters == d->numArguments) {
 115             args.initialize(&d->registers[d->firstParameterIndex], d->numArguments);
 116             return;
 117         }
 118
 119         unsigned parametersLength = min(d->numParameters, d->numArguments);
 120         unsigned i = 0;
 121         for (; i < parametersLength; ++i)
 122             args.append(d->registers[d->firstParameterIndex + i].jsValue());
 123         for (; i < d->numArguments; ++i)
 124             args.append(d->extraArguments[i - d->numParameters].jsValue());
 125         return;
 126     }
 127
 128     unsigned parametersLength = min(d->numParameters, d->numArguments);
 129     unsigned i = 0;
 130     for (; i < parametersLength; ++i) {
 131         if (!d->deletedArguments[i])
 132             args.append(d->registers[d->firstParameterIndex + i].jsValue());
 133         else
 134             args.append(get(exec, i));
 135     }
 136     for (; i < d->numArguments; ++i) {
 137         if (!d->deletedArguments[i])
 138             args.append(d->extraArguments[i - d->numParameters].jsValue());
 139         else
 140             args.append(get(exec, i));
 141     }
 142 }
 143
 144 bool Arguments::getOwnPropertySlot(ExecState* exec, unsigned i, PropertySlot& slot)
 145 {
 146     if (i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 147         if (i < d->numParameters) {
 148             slot.setRegisterSlot(&d->registers[d->firstParameterIndex + i]);
 149         } else
 150             slot.setValue(d->extraArguments[i - d->numParameters].jsValue());
 151         return true;
 152     }
 153
 154     return JSObject::getOwnPropertySlot(exec, Identifier(exec, UString::from(i)), slot);
 155 }
 156
 157 bool Arguments::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
 158 {
 159     bool isArrayIndex;
 160     unsigned i = propertyName.toArrayIndex(&isArrayIndex);
 161     if (isArrayIndex && i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 162         if (i < d->numParameters) {
 163             slot.setRegisterSlot(&d->registers[d->firstParameterIndex + i]);
 164         } else
 165             slot.setValue(d->extraArguments[i - d->numParameters].jsValue());
 166         return true;
 167     }
 168
 169     if (propertyName == exec->propertyNames().length && LIKELY(!d->overrodeLength)) {
 170         slot.setValue(jsNumber(exec, d->numArguments));
 171         return true;
 172     }
 173
 174     if (propertyName == exec->propertyNames().callee && LIKELY(!d->overrodeCallee)) {
 175         slot.setValue(d->callee);
 176         return true;
 177     }
 178
 179     return JSObject::getOwnPropertySlot(exec, propertyName, slot);
 180 }
 181
 182 bool Arguments::getOwnPropertyDescriptor(ExecState* exec, const Identifier& propertyName, PropertyDescriptor& descriptor)
 183 {
 184     bool isArrayIndex;
 185     unsigned i = propertyName.toArrayIndex(&isArrayIndex);
 186     if (isArrayIndex && i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 187         if (i < d->numParameters) {
 188             descriptor.setDescriptor(d->registers[d->firstParameterIndex + i].jsValue(), DontEnum);
 189         } else
 190             descriptor.setDescriptor(d->extraArguments[i - d->numParameters].jsValue(), DontEnum);
 191         return true;
 192     }
 193
 194     if (propertyName == exec->propertyNames().length && LIKELY(!d->overrodeLength)) {
 195         descriptor.setDescriptor(jsNumber(exec, d->numArguments), DontEnum);
 196         return true;
 197     }
 198
 199     if (propertyName == exec->propertyNames().callee && LIKELY(!d->overrodeCallee)) {
 200         descriptor.setDescriptor(d->callee, DontEnum);
 201         return true;
 202     }
 203
 204     return JSObject::getOwnPropertyDescriptor(exec, propertyName, descriptor);
 205 }
 206
 207 void Arguments::getOwnPropertyNames(ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
 208 {
 209     if (mode == IncludeDontEnumProperties) {
 210         for (unsigned i = 0; i < d->numArguments; ++i) {
 211             if (!d->deletedArguments || !d->deletedArguments[i])
 212                 propertyNames.add(Identifier(exec, UString::from(i)));
 213         }
 214         propertyNames.add(exec->propertyNames().callee);
 215         propertyNames.add(exec->propertyNames().length);
 216     }
 217     JSObject::getOwnPropertyNames(exec, propertyNames, mode);
 218 }
 219
 220 void Arguments::put(ExecState* exec, unsigned i, JSValue value, PutPropertySlot& slot)
 221 {
 222     if (i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 223         if (i < d->numParameters)
 224             d->registers[d->firstParameterIndex + i] = JSValue(value);
 225         else
 226             d->extraArguments[i - d->numParameters] = JSValue(value);
 227         return;
 228     }
 229
 230     JSObject::put(exec, Identifier(exec, UString::from(i)), value, slot);
 231 }
 232
 233 void Arguments::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
 234 {
 235     bool isArrayIndex;
 236     unsigned i = propertyName.toArrayIndex(&isArrayIndex);
 237     if (isArrayIndex && i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 238         if (i < d->numParameters)
 239             d->registers[d->firstParameterIndex + i] = JSValue(value);
 240         else
 241             d->extraArguments[i - d->numParameters] = JSValue(value);
 242         return;
 243     }
 244
 245     if (propertyName == exec->propertyNames().length && !d->overrodeLength) {
 246         d->overrodeLength = true;
 247         putDirect(propertyName, value, DontEnum);
 248         return;
 249     }
 250
 251     if (propertyName == exec->propertyNames().callee && !d->overrodeCallee) {
 252         d->overrodeCallee = true;
 253         putDirect(propertyName, value, DontEnum);
 254         return;
 255     }
 256
 257     JSObject::put(exec, propertyName, value, slot);
 258 }
 259
 260 bool Arguments::deleteProperty(ExecState* exec, unsigned i)
 261 {
 262     if (i < d->numArguments) {
 263         if (!d->deletedArguments) {
 264             d->deletedArguments.set(new bool[d->numArguments]);
 265             memset(d->deletedArguments.get(), 0, sizeof(bool) * d->numArguments);
 266         }
 267         if (!d->deletedArguments[i]) {
 268             d->deletedArguments[i] = true;
 269             return true;
 270         }
 271     }
 272
 273     return JSObject::deleteProperty(exec, Identifier(exec, UString::from(i)));
 274 }
 275
 276 bool Arguments::deleteProperty(ExecState* exec, const Identifier& propertyName)
 277 {
 278     bool isArrayIndex;
 279     unsigned i = propertyName.toArrayIndex(&isArrayIndex);
 280     if (isArrayIndex && i < d->numArguments) {
 281         if (!d->deletedArguments) {
 282             d->deletedArguments.set(new bool[d->numArguments]);
 283             memset(d->deletedArguments.get(), 0, sizeof(bool) * d->numArguments);
 284         }
 285         if (!d->deletedArguments[i]) {
 286             d->deletedArguments[i] = true;
 287             return true;
 288         }
 289     }
 290
 291     if (propertyName == exec->propertyNames().length && !d->overrodeLength) {
 292         d->overrodeLength = true;
 293         return true;
 294     }
 295
 296     if (propertyName == exec->propertyNames().callee && !d->overrodeCallee) {
 297         d->overrodeCallee = true;
 298         return true;
 299     }
 300
 301     return JSObject::deleteProperty(exec, propertyName);
 302 }
 303
 304 } // namespace JSC