runtime/JSFunction.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 "JSFunction.h"
  27
  28 #include "CodeBlock.h"
  29 #include "CommonIdentifiers.h"
  30 #include "CallFrame.h"
  31 #include "FunctionPrototype.h"
  32 #include "JSGlobalObject.h"
  33 #include "Interpreter.h"
  34 #include "ObjectPrototype.h"
  35 #include "Parser.h"
  36 #include "PropertyNameArray.h"
  37 #include "ScopeChainMark.h"
  38
  39 using namespace WTF;
  40 using namespace Unicode;
  41
  42 namespace JSC {
  43
  44 ASSERT_CLASS_FITS_IN_CELL(JSFunction);
  45
  46 const ClassInfo JSFunction::info = { "Function", &InternalFunction::info, 0, 0 };
  47
  48 JSFunction::JSFunction(ExecState* exec, PassRefPtr<Structure> structure, int length, const Identifier& name, NativeFunction func)
  49     : Base(&exec->globalData(), structure, name)
  50 #if ENABLE(JIT)
  51     , m_body(FunctionBodyNode::createNativeThunk(&exec->globalData()))
  52 #else
  53     , m_body(0)
  54 #endif
  55 {
  56 #if ENABLE(JIT)
  57     setNativeFunction(func);
  58     putDirect(exec->propertyNames().length, jsNumber(exec, length), DontDelete | ReadOnly | DontEnum);
  59 #else
  60     UNUSED_PARAM(length);
  61     UNUSED_PARAM(func);
  62     ASSERT_NOT_REACHED();
  63 #endif
  64 }
  65
  66 JSFunction::JSFunction(ExecState* exec, const Identifier& name, FunctionBodyNode* body, ScopeChainNode* scopeChainNode)
  67     : Base(&exec->globalData(), exec->lexicalGlobalObject()->functionStructure(), name)
  68     , m_body(body)
  69 {
  70     setScopeChain(scopeChainNode);
  71 }
  72
  73 JSFunction::~JSFunction()
  74 {
  75     // JIT code for other functions may have had calls linked directly to the code for this function; these links
  76     // are based on a check for the this pointer value for this JSFunction - which will no longer be valid once
  77     // this memory is freed and may be reused (potentially for another, different JSFunction).
  78 #if ENABLE(JIT_OPTIMIZE_CALL)
  79     if (m_body && m_body->isGenerated())
  80         m_body->generatedBytecode().unlinkCallers();
  81 #endif
  82     if (!isHostFunction())
  83         scopeChain().~ScopeChain(); // FIXME: Don't we need to do this in the interpreter too?
  84 }
  85
  86 void JSFunction::mark()
  87 {
  88     Base::mark();
  89     m_body->mark();
  90     if (!isHostFunction())
  91         scopeChain().mark();
  92 }
  93
  94 CallType JSFunction::getCallData(CallData& callData)
  95 {
  96     if (isHostFunction()) {
  97         callData.native.function = nativeFunction();
  98         return CallTypeHost;
  99     }
 100     callData.js.functionBody = m_body.get();
 101     callData.js.scopeChain = scopeChain().node();
 102     return CallTypeJS;
 103 }
 104
 105 JSValue JSFunction::call(ExecState* exec, JSValue thisValue, const ArgList& args)
 106 {
 107     ASSERT(!isHostFunction());
 108     return exec->interpreter()->execute(m_body.get(), exec, this, thisValue.toThisObject(exec), args, scopeChain().node(), exec->exceptionSlot());
 109 }
 110
 111 JSValue JSFunction::argumentsGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
 112 {
 113     JSFunction* thisObj = asFunction(slot.slotBase());
 114     ASSERT(!thisObj->isHostFunction());
 115     return exec->interpreter()->retrieveArguments(exec, thisObj);
 116 }
 117
 118 JSValue JSFunction::callerGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
 119 {
 120     JSFunction* thisObj = asFunction(slot.slotBase());
 121     ASSERT(!thisObj->isHostFunction());
 122     return exec->interpreter()->retrieveCaller(exec, thisObj);
 123 }
 124
 125 JSValue JSFunction::lengthGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
 126 {
 127     JSFunction* thisObj = asFunction(slot.slotBase());
 128     ASSERT(!thisObj->isHostFunction());
 129     return jsNumber(exec, thisObj->m_body->parameterCount());
 130 }
 131
 132 bool JSFunction::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
 133 {
 134     if (isHostFunction())
 135         return Base::getOwnPropertySlot(exec, propertyName, slot);
 136
 137     if (propertyName == exec->propertyNames().prototype) {
 138         JSValue* location = getDirectLocation(propertyName);
 139
 140         if (!location) {
 141             JSObject* prototype = new (exec) JSObject(scopeChain().globalObject()->emptyObjectStructure());
 142             prototype->putDirect(exec->propertyNames().constructor, this, DontEnum);
 143             putDirect(exec->propertyNames().prototype, prototype, DontDelete);
 144             location = getDirectLocation(propertyName);
 145         }
 146
 147         slot.setValueSlot(this, location, offsetForLocation(location));
 148     }
 149
 150     if (propertyName == exec->propertyNames().arguments) {
 151         slot.setCustom(this, argumentsGetter);
 152         return true;
 153     }
 154
 155     if (propertyName == exec->propertyNames().length) {
 156         slot.setCustom(this, lengthGetter);
 157         return true;
 158     }
 159
 160     if (propertyName == exec->propertyNames().caller) {
 161         slot.setCustom(this, callerGetter);
 162         return true;
 163     }
 164
 165     return Base::getOwnPropertySlot(exec, propertyName, slot);
 166 }
 167
 168 void JSFunction::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
 169 {
 170     if (isHostFunction()) {
 171         Base::put(exec, propertyName, value, slot);
 172         return;
 173     }
 174     if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
 175         return;
 176     Base::put(exec, propertyName, value, slot);
 177 }
 178
 179 bool JSFunction::deleteProperty(ExecState* exec, const Identifier& propertyName)
 180 {
 181     if (isHostFunction())
 182         return Base::deleteProperty(exec, propertyName);
 183     if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
 184         return false;
 185     return Base::deleteProperty(exec, propertyName);
 186 }
 187
 188 // ECMA 13.2.2 [[Construct]]
 189 ConstructType JSFunction::getConstructData(ConstructData& constructData)
 190 {
 191     if (isHostFunction())
 192         return ConstructTypeNone;
 193     constructData.js.functionBody = m_body.get();
 194     constructData.js.scopeChain = scopeChain().node();
 195     return ConstructTypeJS;
 196 }
 197
 198 JSObject* JSFunction::construct(ExecState* exec, const ArgList& args)
 199 {
 200     ASSERT(!isHostFunction());
 201     Structure* structure;
 202     JSValue prototype = get(exec, exec->propertyNames().prototype);
 203     if (prototype.isObject())
 204         structure = asObject(prototype)->inheritorID();
 205     else
 206         structure = exec->lexicalGlobalObject()->emptyObjectStructure();
 207     JSObject* thisObj = new (exec) JSObject(structure);
 208
 209     JSValue result = exec->interpreter()->execute(m_body.get(), exec, this, thisObj, args, scopeChain().node(), exec->exceptionSlot());
 210     if (exec->hadException() || !result.isObject())
 211         return thisObj;
 212     return asObject(result);
 213 }
 214
 215 } // namespace JSC