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 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::mark()
  47 {
  48     JSObject::mark();
  49
  50     if (d->registerArray) {
  51         for (unsigned i = 0; i < d->numParameters; ++i) {
  52             if (!d->registerArray[i].marked())
  53                 d->registerArray[i].mark();
  54         }
  55     }
  56
  57     if (d->extraArguments) {
  58         unsigned numExtraArguments = d->numArguments - d->numParameters;
  59         for (unsigned i = 0; i < numExtraArguments; ++i) {
  60             if (!d->extraArguments[i].marked())
  61                 d->extraArguments[i].mark();
  62         }
  63     }
  64
  65     if (!d->callee->marked())
  66         d->callee->mark();
  67
  68     if (d->activation && !d->activation->marked())
  69         d->activation->mark();
  70 }
  71
  72 void Arguments::copyToRegisters(ExecState* exec, Register* buffer, uint32_t maxSize)
  73 {
  74     if (UNLIKELY(d->overrodeLength)) {
  75         unsigned length = min(get(exec, exec->propertyNames().length).toUInt32(exec), maxSize);
  76         for (unsigned i = 0; i < length; i++)
  77             buffer[i] = get(exec, i);
  78         return;
  79     }
  80
  81     if (LIKELY(!d->deletedArguments)) {
  82         unsigned parametersLength = min(min(d->numParameters, d->numArguments), maxSize);
  83         unsigned i = 0;
  84         for (; i < parametersLength; ++i)
  85             buffer[i] = d->registers[d->firstParameterIndex + i].jsValue();
  86         for (; i < d->numArguments; ++i)
  87             buffer[i] = d->extraArguments[i - d->numParameters].jsValue();
  88         return;
  89     }
  90
  91     unsigned parametersLength = min(min(d->numParameters, d->numArguments), maxSize);
  92     unsigned i = 0;
  93     for (; i < parametersLength; ++i) {
  94         if (!d->deletedArguments[i])
  95             buffer[i] = d->registers[d->firstParameterIndex + i].jsValue();
  96         else
  97             buffer[i] = get(exec, i);
  98     }
  99     for (; i < d->numArguments; ++i) {
 100         if (!d->deletedArguments[i])
 101             buffer[i] = d->extraArguments[i - d->numParameters].jsValue();
 102         else
 103             buffer[i] = get(exec, i);
 104     }
 105 }
 106
 107 void Arguments::fillArgList(ExecState* exec, MarkedArgumentBuffer& args)
 108 {
 109     if (UNLIKELY(d->overrodeLength)) {
 110         unsigned length = get(exec, exec->propertyNames().length).toUInt32(exec);
 111         for (unsigned i = 0; i < length; i++)
 112             args.append(get(exec, i));
 113         return;
 114     }
 115
 116     if (LIKELY(!d->deletedArguments)) {
 117         if (LIKELY(!d->numParameters)) {
 118             args.initialize(d->extraArguments, d->numArguments);
 119             return;
 120         }
 121
 122         if (d->numParameters == d->numArguments) {
 123             args.initialize(&d->registers[d->firstParameterIndex], d->numArguments);
 124             return;
 125         }
 126
 127         unsigned parametersLength = min(d->numParameters, d->numArguments);
 128         unsigned i = 0;
 129         for (; i < parametersLength; ++i)
 130             args.append(d->registers[d->firstParameterIndex + i].jsValue());
 131         for (; i < d->numArguments; ++i)
 132             args.append(d->extraArguments[i - d->numParameters].jsValue());
 133         return;
 134     }
 135
 136     unsigned parametersLength = min(d->numParameters, d->numArguments);
 137     unsigned i = 0;
 138     for (; i < parametersLength; ++i) {
 139         if (!d->deletedArguments[i])
 140             args.append(d->registers[d->firstParameterIndex + i].jsValue());
 141         else
 142             args.append(get(exec, i));
 143     }
 144     for (; i < d->numArguments; ++i) {
 145         if (!d->deletedArguments[i])
 146             args.append(d->extraArguments[i - d->numParameters].jsValue());
 147         else
 148             args.append(get(exec, i));
 149     }
 150 }
 151
 152 bool Arguments::getOwnPropertySlot(ExecState* exec, unsigned i, PropertySlot& slot)
 153 {
 154     if (i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 155         if (i < d->numParameters) {
 156             slot.setRegisterSlot(&d->registers[d->firstParameterIndex + i]);
 157         } else
 158             slot.setValue(d->extraArguments[i - d->numParameters].jsValue());
 159         return true;
 160     }
 161
 162     return JSObject::getOwnPropertySlot(exec, Identifier(exec, UString::from(i)), slot);
 163 }
 164
 165 bool Arguments::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
 166 {
 167     bool isArrayIndex;
 168     unsigned i = propertyName.toArrayIndex(&isArrayIndex);
 169     if (isArrayIndex && i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 170         if (i < d->numParameters) {
 171             slot.setRegisterSlot(&d->registers[d->firstParameterIndex + i]);
 172         } else
 173             slot.setValue(d->extraArguments[i - d->numParameters].jsValue());
 174         return true;
 175     }
 176
 177     if (propertyName == exec->propertyNames().length && LIKELY(!d->overrodeLength)) {
 178         slot.setValue(jsNumber(exec, d->numArguments));
 179         return true;
 180     }
 181
 182     if (propertyName == exec->propertyNames().callee && LIKELY(!d->overrodeCallee)) {
 183         slot.setValue(d->callee);
 184         return true;
 185     }
 186
 187     return JSObject::getOwnPropertySlot(exec, propertyName, slot);
 188 }
 189
 190 void Arguments::put(ExecState* exec, unsigned i, JSValue value, PutPropertySlot& slot)
 191 {
 192     if (i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 193         if (i < d->numParameters)
 194             d->registers[d->firstParameterIndex + i] = JSValue(value);
 195         else
 196             d->extraArguments[i - d->numParameters] = JSValue(value);
 197         return;
 198     }
 199
 200     JSObject::put(exec, Identifier(exec, UString::from(i)), value, slot);
 201 }
 202
 203 void Arguments::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
 204 {
 205     bool isArrayIndex;
 206     unsigned i = propertyName.toArrayIndex(&isArrayIndex);
 207     if (isArrayIndex && i < d->numArguments && (!d->deletedArguments || !d->deletedArguments[i])) {
 208         if (i < d->numParameters)
 209             d->registers[d->firstParameterIndex + i] = JSValue(value);
 210         else
 211             d->extraArguments[i - d->numParameters] = JSValue(value);
 212         return;
 213     }
 214
 215     if (propertyName == exec->propertyNames().length && !d->overrodeLength) {
 216         d->overrodeLength = true;
 217         putDirect(propertyName, value, DontEnum);
 218         return;
 219     }
 220
 221     if (propertyName == exec->propertyNames().callee && !d->overrodeCallee) {
 222         d->overrodeCallee = true;
 223         putDirect(propertyName, value, DontEnum);
 224         return;
 225     }
 226
 227     JSObject::put(exec, propertyName, value, slot);
 228 }
 229
 230 bool Arguments::deleteProperty(ExecState* exec, unsigned i)
 231 {
 232     if (i < d->numArguments) {
 233         if (!d->deletedArguments) {
 234             d->deletedArguments.set(new bool[d->numArguments]);
 235             memset(d->deletedArguments.get(), 0, sizeof(bool) * d->numArguments);
 236         }
 237         if (!d->deletedArguments[i]) {
 238             d->deletedArguments[i] = true;
 239             return true;
 240         }
 241     }
 242
 243     return JSObject::deleteProperty(exec, Identifier(exec, UString::from(i)));
 244 }
 245
 246 bool Arguments::deleteProperty(ExecState* exec, const Identifier& propertyName)
 247 {
 248     bool isArrayIndex;
 249     unsigned i = propertyName.toArrayIndex(&isArrayIndex);
 250     if (isArrayIndex && i < d->numArguments) {
 251         if (!d->deletedArguments) {
 252             d->deletedArguments.set(new bool[d->numArguments]);
 253             memset(d->deletedArguments.get(), 0, sizeof(bool) * d->numArguments);
 254         }
 255         if (!d->deletedArguments[i]) {
 256             d->deletedArguments[i] = true;
 257             return true;
 258         }
 259     }
 260
 261     if (propertyName == exec->propertyNames().length && !d->overrodeLength) {
 262         d->overrodeLength = true;
 263         return true;
 264     }
 265
 266     if (propertyName == exec->propertyNames().callee && !d->overrodeCallee) {
 267         d->overrodeCallee = true;
 268         return true;
 269     }
 270
 271     return JSObject::deleteProperty(exec, propertyName);
 272 }
 273
 274 } // namespace JSC