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, const Identifier& name, FunctionBodyNode* body, ScopeChainNode* scopeChainNode)
  49     : Base(&exec->globalData(), exec->lexicalGlobalObject()->functionStructure(), name)
  50     , m_body(body)
  51     , m_scopeChain(scopeChainNode)
  52 {
  53 }
  54
  55 JSFunction::~JSFunction()
  56 {
  57 #if ENABLE(JIT)
  58     // JIT code for other functions may have had calls linked directly to the code for this function; these links
  59     // are based on a check for the this pointer value for this JSFunction - which will no longer be valid once
  60     // this memory is freed and may be reused (potentially for another, different JSFunction).
  61     if (m_body && m_body->isGenerated())
  62         m_body->generatedBytecode().unlinkCallers();
  63 #endif
  64 }
  65
  66 void JSFunction::mark()
  67 {
  68     Base::mark();
  69     m_body->mark();
  70     m_scopeChain.mark();
  71 }
  72
  73 CallType JSFunction::getCallData(CallData& callData)
  74 {
  75     callData.js.functionBody = m_body.get();
  76     callData.js.scopeChain = m_scopeChain.node();
  77     return CallTypeJS;
  78 }
  79
  80 JSValuePtr JSFunction::call(ExecState* exec, JSValuePtr thisValue, const ArgList& args)
  81 {
  82     return exec->interpreter()->execute(m_body.get(), exec, this, thisValue.toThisObject(exec), args, m_scopeChain.node(), exec->exceptionSlot());
  83 }
  84
  85 JSValuePtr JSFunction::argumentsGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
  86 {
  87     JSFunction* thisObj = asFunction(slot.slotBase());
  88     return exec->interpreter()->retrieveArguments(exec, thisObj);
  89 }
  90
  91 JSValuePtr JSFunction::callerGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
  92 {
  93     JSFunction* thisObj = asFunction(slot.slotBase());
  94     return exec->interpreter()->retrieveCaller(exec, thisObj);
  95 }
  96
  97 JSValuePtr JSFunction::lengthGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
  98 {
  99     JSFunction* thisObj = asFunction(slot.slotBase());
 100     return jsNumber(exec, thisObj->m_body->parameterCount());
 101 }
 102
 103 bool JSFunction::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
 104 {
 105     if (propertyName == exec->propertyNames().prototype) {
 106         JSValuePtr* location = getDirectLocation(propertyName);
 107
 108         if (!location) {
 109             JSObject* prototype = new (exec) JSObject(m_scopeChain.globalObject()->emptyObjectStructure());
 110             prototype->putDirect(exec->propertyNames().constructor, this, DontEnum);
 111             putDirect(exec->propertyNames().prototype, prototype, DontDelete);
 112             location = getDirectLocation(propertyName);
 113         }
 114
 115         slot.setValueSlot(this, location, offsetForLocation(location));
 116     }
 117
 118     if (propertyName == exec->propertyNames().arguments) {
 119         slot.setCustom(this, argumentsGetter);
 120         return true;
 121     }
 122
 123     if (propertyName == exec->propertyNames().length) {
 124         slot.setCustom(this, lengthGetter);
 125         return true;
 126     }
 127
 128     if (propertyName == exec->propertyNames().caller) {
 129         slot.setCustom(this, callerGetter);
 130         return true;
 131     }
 132
 133     return Base::getOwnPropertySlot(exec, propertyName, slot);
 134 }
 135
 136 void JSFunction::put(ExecState* exec, const Identifier& propertyName, JSValuePtr value, PutPropertySlot& slot)
 137 {
 138     if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
 139         return;
 140     Base::put(exec, propertyName, value, slot);
 141 }
 142
 143 bool JSFunction::deleteProperty(ExecState* exec, const Identifier& propertyName)
 144 {
 145     if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
 146         return false;
 147     return Base::deleteProperty(exec, propertyName);
 148 }
 149
 150 // ECMA 13.2.2 [[Construct]]
 151 ConstructType JSFunction::getConstructData(ConstructData& constructData)
 152 {
 153     constructData.js.functionBody = m_body.get();
 154     constructData.js.scopeChain = m_scopeChain.node();
 155     return ConstructTypeJS;
 156 }
 157
 158 JSObject* JSFunction::construct(ExecState* exec, const ArgList& args)
 159 {
 160     Structure* structure;
 161     JSValuePtr prototype = get(exec, exec->propertyNames().prototype);
 162     if (prototype.isObject())
 163         structure = asObject(prototype)->inheritorID();
 164     else
 165         structure = exec->lexicalGlobalObject()->emptyObjectStructure();
 166     JSObject* thisObj = new (exec) JSObject(structure);
 167
 168     JSValuePtr result = exec->interpreter()->execute(m_body.get(), exec, this, thisObj, args, m_scopeChain.node(), exec->exceptionSlot());
 169     if (exec->hadException() || !result.isObject())
 170         return thisObj;
 171     return asObject(result);
 172 }
 173
 174 } // namespace JSC