1 /*
   2  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.nashorn.internal.runtime;
  27 
  28 import static jdk.nashorn.internal.codegen.CompilerConstants.staticCallNoLookup;
  29 import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCall;
  30 import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup;
  31 import static jdk.nashorn.internal.codegen.ObjectClassGenerator.OBJECT_FIELDS_ONLY;
  32 import static jdk.nashorn.internal.lookup.Lookup.MH;
  33 import static jdk.nashorn.internal.runtime.ECMAErrors.referenceError;
  34 import static jdk.nashorn.internal.runtime.ECMAErrors.typeError;
  35 import static jdk.nashorn.internal.runtime.JSType.UNDEFINED_DOUBLE;
  36 import static jdk.nashorn.internal.runtime.JSType.UNDEFINED_INT;
  37 import static jdk.nashorn.internal.runtime.JSType.UNDEFINED_LONG;
  38 import static jdk.nashorn.internal.runtime.PropertyDescriptor.CONFIGURABLE;
  39 import static jdk.nashorn.internal.runtime.PropertyDescriptor.ENUMERABLE;
  40 import static jdk.nashorn.internal.runtime.PropertyDescriptor.GET;
  41 import static jdk.nashorn.internal.runtime.PropertyDescriptor.SET;
  42 import static jdk.nashorn.internal.runtime.PropertyDescriptor.VALUE;
  43 import static jdk.nashorn.internal.runtime.PropertyDescriptor.WRITABLE;
  44 import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED;
  45 import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.INVALID_PROGRAM_POINT;
  46 import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.isValid;
  47 import static jdk.nashorn.internal.runtime.arrays.ArrayIndex.getArrayIndex;
  48 import static jdk.nashorn.internal.runtime.arrays.ArrayIndex.isValidArrayIndex;
  49 import static jdk.nashorn.internal.runtime.linker.NashornGuards.explicitInstanceOfCheck;
  50 
  51 import java.lang.invoke.MethodHandle;
  52 import java.lang.invoke.MethodHandles;
  53 import java.lang.invoke.MethodType;
  54 import java.lang.invoke.SwitchPoint;
  55 import java.util.AbstractMap;
  56 import java.util.ArrayList;
  57 import java.util.Arrays;
  58 import java.util.Collection;
  59 import java.util.Collections;
  60 import java.util.HashSet;
  61 import java.util.Iterator;
  62 import java.util.LinkedHashSet;
  63 import java.util.List;
  64 import java.util.Map;
  65 import java.util.Set;
  66 import jdk.internal.dynalink.CallSiteDescriptor;
  67 import jdk.internal.dynalink.linker.GuardedInvocation;
  68 import jdk.internal.dynalink.linker.LinkRequest;
  69 import jdk.internal.dynalink.support.CallSiteDescriptorFactory;
  70 import jdk.nashorn.internal.codegen.CompilerConstants.Call;
  71 import jdk.nashorn.internal.codegen.ObjectClassGenerator;
  72 import jdk.nashorn.internal.codegen.types.Type;
  73 import jdk.nashorn.internal.lookup.Lookup;
  74 import jdk.nashorn.internal.objects.AccessorPropertyDescriptor;
  75 import jdk.nashorn.internal.objects.DataPropertyDescriptor;
  76 import jdk.nashorn.internal.objects.Global;
  77 import jdk.nashorn.internal.objects.NativeArray;
  78 import jdk.nashorn.internal.runtime.arrays.ArrayData;
  79 import jdk.nashorn.internal.runtime.arrays.ArrayIndex;
  80 import jdk.nashorn.internal.runtime.linker.Bootstrap;
  81 import jdk.nashorn.internal.runtime.linker.LinkerCallSite;
  82 import jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor;
  83 import jdk.nashorn.internal.runtime.linker.NashornGuards;
  84 
  85 /**
  86  * Base class for generic JavaScript objects.
  87  * <p>
  88  * Notes:
  89  * <ul>
  90  * <li>The map is used to identify properties in the object.</li>
  91  * <li>If the map is modified then it must be cloned and replaced.  This notifies
  92  *     any code that made assumptions about the object that things have changed.
  93  *     Ex. CallSites that have been validated must check to see if the map has
  94  *     changed (or a map from a different object type) and hence relink the method
  95  *     to call.</li>
  96  * <li>Modifications of the map include adding/deleting attributes or changing a
  97  *     function field value.</li>
  98  * </ul>
  99  */
 100 
 101 public abstract class ScriptObject implements PropertyAccess {
 102     /** __proto__ special property name inside object literals. ES6 draft. */
 103     public static final String PROTO_PROPERTY_NAME   = "__proto__";
 104 
 105     /** Search fall back routine name for "no such method" */
 106     static final String NO_SUCH_METHOD_NAME   = "__noSuchMethod__";
 107 
 108     /** Search fall back routine name for "no such property" */
 109     static final String NO_SUCH_PROPERTY_NAME = "__noSuchProperty__";
 110 
 111     /** Per ScriptObject flag - is this a scope object? */
 112     public static final int IS_SCOPE       = 1 << 0;
 113 
 114     /** Per ScriptObject flag - is this an array object? */
 115     public static final int IS_ARRAY       = 1 << 1;
 116 
 117     /** Per ScriptObject flag - is this an arguments object? */
 118     public static final int IS_ARGUMENTS   = 1 << 2;
 119 
 120     /** Is length property not-writable? */
 121     public static final int IS_LENGTH_NOT_WRITABLE = 1 << 3;
 122 
 123     /** Is this a builtin object? */
 124     public static final int IS_BUILTIN = 1 << 4;
 125 
 126     /**
 127      * Spill growth rate - by how many elements does {@link ScriptObject#primitiveSpill} and
 128      * {@link ScriptObject#objectSpill} when full
 129      */
 130     public static final int SPILL_RATE = 8;
 131 
 132     /** Map to property information and accessor functions. Ordered by insertion. */
 133     private PropertyMap map;
 134 
 135     /** objects proto. */
 136     private ScriptObject proto;
 137 
 138     /** Object flags. */
 139     private int flags;
 140 
 141     /** Area for primitive properties added to object after instantiation, see {@link AccessorProperty} */
 142     protected long[]   primitiveSpill;
 143 
 144     /** Area for reference properties added to object after instantiation, see {@link AccessorProperty} */
 145     protected Object[] objectSpill;
 146 
 147     /**
 148      * Number of elements in the spill. This may be less than the spill array lengths, if not all of
 149      * the allocated memory is in use
 150      */
 151     private int spillLength;
 152 
 153     /** Indexed array data. */
 154     private ArrayData arrayData;
 155 
 156     /** Method handle to retrieve prototype of this object */
 157     public static final MethodHandle GETPROTO      = findOwnMH_V("getProto", ScriptObject.class);
 158 
 159     static final MethodHandle MEGAMORPHIC_GET    = findOwnMH_V("megamorphicGet", Object.class, String.class, boolean.class);
 160     static final MethodHandle GLOBALFILTER       = findOwnMH_S("globalFilter", Object.class, Object.class);
 161 
 162     private static final MethodHandle TRUNCATINGFILTER   = findOwnMH_S("truncatingFilter", Object[].class, int.class, Object[].class);
 163     private static final MethodHandle KNOWNFUNCPROPGUARD = findOwnMH_S("knownFunctionPropertyGuard", boolean.class, Object.class, PropertyMap.class, MethodHandle.class, Object.class, ScriptFunction.class);
 164 
 165     private static final ArrayList<MethodHandle> PROTO_FILTERS = new ArrayList<>();
 166 
 167     /** Method handle for getting the array data */
 168     public static final Call GET_ARRAY          = virtualCall(MethodHandles.lookup(), ScriptObject.class, "getArray", ArrayData.class);
 169 
 170     /** Method handle for getting the property map - debugging purposes */
 171     public static final Call GET_MAP            = virtualCall(MethodHandles.lookup(), ScriptObject.class, "getMap", PropertyMap.class);
 172 
 173     /** Method handle for setting the array data */
 174     public static final Call SET_ARRAY          = virtualCall(MethodHandles.lookup(), ScriptObject.class, "setArray", void.class, ArrayData.class);
 175 
 176     /** Method handle for getting a function argument at a given index. Used from MapCreator */
 177     public static final Call GET_ARGUMENT       = virtualCall(MethodHandles.lookup(), ScriptObject.class, "getArgument", Object.class, int.class);
 178 
 179     /** Method handle for setting a function argument at a given index. Used from MapCreator */
 180     public static final Call SET_ARGUMENT       = virtualCall(MethodHandles.lookup(), ScriptObject.class, "setArgument", void.class, int.class, Object.class);
 181 
 182     /** Method handle for getting the proto of a ScriptObject */
 183     public static final Call GET_PROTO          = virtualCallNoLookup(ScriptObject.class, "getProto", ScriptObject.class);
 184 
 185     /** Method handle for getting the proto of a ScriptObject */
 186     public static final Call GET_PROTO_DEPTH    = virtualCallNoLookup(ScriptObject.class, "getProto", ScriptObject.class, int.class);
 187 
 188     /** Method handle for setting the proto of a ScriptObject */
 189     public static final Call SET_GLOBAL_OBJECT_PROTO = staticCallNoLookup(ScriptObject.class, "setGlobalObjectProto", void.class, ScriptObject.class);
 190 
 191     /** Method handle for setting the proto of a ScriptObject after checking argument */
 192     public static final Call SET_PROTO_FROM_LITERAL    = virtualCallNoLookup(ScriptObject.class, "setProtoFromLiteral", void.class, Object.class);
 193 
 194     /** Method handle for setting the user accessors of a ScriptObject */
 195     //TODO fastpath this
 196     public static final Call SET_USER_ACCESSORS = virtualCall(MethodHandles.lookup(), ScriptObject.class, "setUserAccessors", void.class, String.class, ScriptFunction.class, ScriptFunction.class);
 197 
 198     static final MethodHandle[] SET_SLOW = new MethodHandle[] {
 199         findOwnMH_V("set", void.class, Object.class, int.class, boolean.class),
 200         findOwnMH_V("set", void.class, Object.class, long.class, boolean.class),
 201         findOwnMH_V("set", void.class, Object.class, double.class, boolean.class),
 202         findOwnMH_V("set", void.class, Object.class, Object.class, boolean.class)
 203     };
 204 
 205     /** Method handle to reset the map of this ScriptObject */
 206     public static final Call SET_MAP = virtualCallNoLookup(ScriptObject.class, "setMap", void.class, PropertyMap.class);
 207 
 208     static final MethodHandle CAS_MAP           = findOwnMH_V("compareAndSetMap", boolean.class, PropertyMap.class, PropertyMap.class);
 209     static final MethodHandle EXTENSION_CHECK   = findOwnMH_V("extensionCheck", boolean.class, boolean.class, String.class);
 210     static final MethodHandle ENSURE_SPILL_SIZE = findOwnMH_V("ensureSpillSize", Object.class, int.class);
 211 
 212     /**
 213      * Constructor
 214      */
 215     public ScriptObject() {
 216         this(null);
 217     }
 218 
 219     /**
 220     * Constructor
 221     *
 222     * @param map {@link PropertyMap} used to create the initial object
 223     */
 224     public ScriptObject(final PropertyMap map) {
 225         if (Context.DEBUG) {
 226             ScriptObject.count++;
 227         }
 228         this.arrayData = ArrayData.EMPTY_ARRAY;
 229         this.setMap(map == null ? PropertyMap.newMap() : map);
 230     }
 231 
 232     /**
 233      * Constructor that directly sets the prototype to {@code proto} and property map to
 234      * {@code map} without invalidating the map as calling {@link #setProto(ScriptObject)}
 235      * would do. This should only be used for objects that are always constructed with the
 236      * same combination of prototype and property map.
 237      *
 238      * @param proto the prototype object
 239      * @param map intial {@link PropertyMap}
 240      */
 241     protected ScriptObject(final ScriptObject proto, final PropertyMap map) {
 242         this(map);
 243         this.proto = proto;
 244     }
 245 
 246     /**
 247      * Constructor used to instantiate spill properties directly. Used from
 248      * SpillObjectCreator.
 249      *
 250      * @param map            property maps
 251      * @param primitiveSpill primitive spills
 252      * @param objectSpill    reference spills
 253      */
 254     public ScriptObject(final PropertyMap map, final long[] primitiveSpill, final Object[] objectSpill) {
 255         this(map);
 256         this.primitiveSpill = primitiveSpill;
 257         this.objectSpill    = objectSpill;
 258         assert primitiveSpill.length == objectSpill.length : " primitive spill pool size is not the same length as object spill pool size";
 259         this.spillLength = spillAllocationLength(primitiveSpill.length);
 260     }
 261 
 262     /**
 263      * Check whether this is a global object
 264      * @return true if global
 265      */
 266     protected boolean isGlobal() {
 267         return false;
 268     }
 269 
 270     private static int alignUp(final int size, final int alignment) {
 271         return size + alignment - 1 & ~(alignment - 1);
 272     }
 273 
 274     /**
 275      * Given a number of properties, return the aligned to SPILL_RATE
 276      * buffer size required for the smallest spill pool needed to
 277      * house them
 278      * @param nProperties number of properties
 279      * @return property buffer length, a multiple of SPILL_RATE
 280      */
 281     public static int spillAllocationLength(final int nProperties) {
 282         return alignUp(nProperties, SPILL_RATE);
 283     }
 284 
 285     /**
 286      * Copy all properties from the source object with their receiver bound to the source.
 287      * This function was known as mergeMap
 288      *
 289      * @param source The source object to copy from.
 290      */
 291     public void addBoundProperties(final ScriptObject source) {
 292         addBoundProperties(source, source.getMap().getProperties());
 293     }
 294 
 295     /**
 296      * Copy all properties from the array with their receiver bound to the source.
 297      *
 298      * @param source The source object to copy from.
 299      * @param properties The array of properties to copy.
 300      */
 301     public void addBoundProperties(final ScriptObject source, final Property[] properties) {
 302         PropertyMap newMap = this.getMap();
 303 
 304         for (final Property property : properties) {
 305             final String key = property.getKey();
 306             final Property oldProp = newMap.findProperty(key);
 307             if (oldProp == null) {
 308                 if (property instanceof UserAccessorProperty) {
 309                     // Note: we copy accessor functions to this object which is semantically different from binding.
 310                     final UserAccessorProperty prop = this.newUserAccessors(key, property.getFlags(), property.getGetterFunction(source), property.getSetterFunction(source));
 311                     newMap = newMap.addPropertyNoHistory(prop);
 312                 } else {
 313                     newMap = newMap.addPropertyBind((AccessorProperty)property, source);
 314                 }
 315             } else {
 316                 // See ECMA section 10.5 Declaration Binding Instantiation
 317                 // step 5 processing each function declaration.
 318                 if (property.isFunctionDeclaration() && !oldProp.isConfigurable()) {
 319                      if (oldProp instanceof UserAccessorProperty ||
 320                          !(oldProp.isWritable() && oldProp.isEnumerable())) {
 321                          throw typeError("cant.redefine.property", key, ScriptRuntime.safeToString(this));
 322                      }
 323                 }
 324             }
 325         }
 326 
 327         this.setMap(newMap);
 328     }
 329 
 330     /**
 331      * Copy all properties from the array with their receiver bound to the source.
 332      *
 333      * @param source The source object to copy from.
 334      * @param properties The collection of accessor properties to copy.
 335      */
 336     public void addBoundProperties(final Object source, final AccessorProperty[] properties) {
 337         PropertyMap newMap = this.getMap();
 338 
 339         for (final AccessorProperty property : properties) {
 340             final String key = property.getKey();
 341 
 342             if (newMap.findProperty(key) == null) {
 343                 newMap = newMap.addPropertyBind(property, source);
 344             }
 345         }
 346 
 347         this.setMap(newMap);
 348     }
 349 
 350     /**
 351      * Bind the method handle to the specified receiver, while preserving its original type (it will just ignore the
 352      * first argument in lieu of the bound argument).
 353      * @param methodHandle Method handle to bind to.
 354      * @param receiver     Object to bind.
 355      * @return Bound method handle.
 356      */
 357     static MethodHandle bindTo(final MethodHandle methodHandle, final Object receiver) {
 358         return MH.dropArguments(MH.bindTo(methodHandle, receiver), 0, methodHandle.type().parameterType(0));
 359     }
 360 
 361     /**
 362      * Return a property iterator.
 363      * @return Property iterator.
 364      */
 365     public Iterator<String> propertyIterator() {
 366         return new KeyIterator(this);
 367     }
 368 
 369     /**
 370      * Return a property value iterator.
 371      * @return Property value iterator.
 372      */
 373     public Iterator<Object> valueIterator() {
 374         return new ValueIterator(this);
 375     }
 376 
 377     /**
 378      * ECMA 8.10.1 IsAccessorDescriptor ( Desc )
 379      * @return true if this has a {@link AccessorPropertyDescriptor} with a getter or a setter
 380      */
 381     public final boolean isAccessorDescriptor() {
 382         return has(GET) || has(SET);
 383     }
 384 
 385     /**
 386      * ECMA 8.10.2 IsDataDescriptor ( Desc )
 387      * @return true if this has a {@link DataPropertyDescriptor}, i.e. the object has a property value and is writable
 388      */
 389     public final boolean isDataDescriptor() {
 390         return has(VALUE) || has(WRITABLE);
 391     }
 392 
 393     /**
 394      * ECMA 8.10.3 IsGenericDescriptor ( Desc )
 395      * @return true if this has a descriptor describing an {@link AccessorPropertyDescriptor} or {@link DataPropertyDescriptor}
 396      */
 397     public final boolean isGenericDescriptor() {
 398         return isAccessorDescriptor() || isDataDescriptor();
 399     }
 400 
 401     /**
 402       * ECMA 8.10.5 ToPropertyDescriptor ( Obj )
 403       *
 404       * @return property descriptor
 405       */
 406     public final PropertyDescriptor toPropertyDescriptor() {
 407         final Global global = Context.getGlobal();
 408 
 409         final PropertyDescriptor desc;
 410         if (isDataDescriptor()) {
 411             if (has(SET) || has(GET)) {
 412                 throw typeError(global, "inconsistent.property.descriptor");
 413             }
 414 
 415             desc = global.newDataDescriptor(UNDEFINED, false, false, false);
 416         } else if (isAccessorDescriptor()) {
 417             if (has(VALUE) || has(WRITABLE)) {
 418                 throw typeError(global, "inconsistent.property.descriptor");
 419             }
 420 
 421             desc = global.newAccessorDescriptor(UNDEFINED, UNDEFINED, false, false);
 422         } else {
 423             desc = global.newGenericDescriptor(false, false);
 424         }
 425 
 426         return desc.fillFrom(this);
 427     }
 428 
 429     /**
 430      * ECMA 8.10.5 ToPropertyDescriptor ( Obj )
 431      *
 432      * @param global  global scope object
 433      * @param obj object to create property descriptor from
 434      *
 435      * @return property descriptor
 436      */
 437     public static PropertyDescriptor toPropertyDescriptor(final Global global, final Object obj) {
 438         if (obj instanceof ScriptObject) {
 439             return ((ScriptObject)obj).toPropertyDescriptor();
 440         }
 441 
 442         throw typeError(global, "not.an.object", ScriptRuntime.safeToString(obj));
 443     }
 444 
 445     /**
 446      * ECMA 8.12.1 [[GetOwnProperty]] (P)
 447      *
 448      * @param key property key
 449      *
 450      * @return Returns the Property Descriptor of the named own property of this
 451      * object, or undefined if absent.
 452      */
 453     public Object getOwnPropertyDescriptor(final String key) {
 454         final Property property = getMap().findProperty(key);
 455 
 456         final Global global = Context.getGlobal();
 457 
 458         if (property != null) {
 459             final ScriptFunction get   = property.getGetterFunction(this);
 460             final ScriptFunction set   = property.getSetterFunction(this);
 461 
 462             final boolean configurable = property.isConfigurable();
 463             final boolean enumerable   = property.isEnumerable();
 464             final boolean writable     = property.isWritable();
 465 
 466             if (property instanceof UserAccessorProperty) {
 467                 return global.newAccessorDescriptor(
 468                     get != null ?
 469                         get :
 470                         UNDEFINED,
 471                     set != null ?
 472                         set :
 473                         UNDEFINED,
 474                     configurable,
 475                     enumerable);
 476             }
 477 
 478             return global.newDataDescriptor(getWithProperty(property), configurable, enumerable, writable);
 479         }
 480 
 481         final int index = getArrayIndex(key);
 482         final ArrayData array = getArray();
 483 
 484         if (array.has(index)) {
 485             return array.getDescriptor(global, index);
 486         }
 487 
 488         return UNDEFINED;
 489     }
 490 
 491     /**
 492      * ECMA 8.12.2 [[GetProperty]] (P)
 493      *
 494      * @param key property key
 495      *
 496      * @return Returns the fully populated Property Descriptor of the named property
 497      * of this object, or undefined if absent.
 498      */
 499     public Object getPropertyDescriptor(final String key) {
 500         final Object res = getOwnPropertyDescriptor(key);
 501 
 502         if (res != UNDEFINED) {
 503             return res;
 504         } else if (getProto() != null) {
 505             return getProto().getOwnPropertyDescriptor(key);
 506         } else {
 507             return UNDEFINED;
 508         }
 509     }
 510 
 511     /**
 512      * ECMA 8.12.9 [[DefineOwnProperty]] (P, Desc, Throw)
 513      *
 514      * @param key the property key
 515      * @param propertyDesc the property descriptor
 516      * @param reject is the property extensible - true means new definitions are rejected
 517      *
 518      * @return true if property was successfully defined
 519      */
 520     public boolean defineOwnProperty(final String key, final Object propertyDesc, final boolean reject) {
 521         final Global             global  = Context.getGlobal();
 522         final PropertyDescriptor desc    = toPropertyDescriptor(global, propertyDesc);
 523         final Object             current = getOwnPropertyDescriptor(key);
 524         final String             name    = JSType.toString(key);
 525 
 526         if (current == UNDEFINED) {
 527             if (isExtensible()) {
 528                 // add a new own property
 529                 addOwnProperty(key, desc);
 530                 return true;
 531             }
 532             // new property added to non-extensible object
 533             if (reject) {
 534                 throw typeError(global, "object.non.extensible", name, ScriptRuntime.safeToString(this));
 535             }
 536             return false;
 537         }
 538 
 539         // modifying an existing property
 540         final PropertyDescriptor currentDesc = (PropertyDescriptor)current;
 541         final PropertyDescriptor newDesc     = desc;
 542 
 543         if (newDesc.type() == PropertyDescriptor.GENERIC && !newDesc.has(CONFIGURABLE) && !newDesc.has(ENUMERABLE)) {
 544             // every descriptor field is absent
 545             return true;
 546         }
 547 
 548         if (newDesc.hasAndEquals(currentDesc)) {
 549             // every descriptor field of the new is same as the current
 550             return true;
 551         }
 552 
 553         if (!currentDesc.isConfigurable()) {
 554             if (newDesc.has(CONFIGURABLE) && newDesc.isConfigurable()) {
 555                 // not configurable can not be made configurable
 556                 if (reject) {
 557                     throw typeError(global, "cant.redefine.property", name, ScriptRuntime.safeToString(this));
 558                 }
 559                 return false;
 560             }
 561 
 562             if (newDesc.has(ENUMERABLE) &&
 563                 currentDesc.isEnumerable() != newDesc.isEnumerable()) {
 564                 // cannot make non-enumerable as enumerable or vice-versa
 565                 if (reject) {
 566                     throw typeError(global, "cant.redefine.property", name, ScriptRuntime.safeToString(this));
 567                 }
 568                 return false;
 569             }
 570         }
 571 
 572         int propFlags = Property.mergeFlags(currentDesc, newDesc);
 573         Property property = getMap().findProperty(key);
 574 
 575         if (currentDesc.type() == PropertyDescriptor.DATA &&
 576                 (newDesc.type() == PropertyDescriptor.DATA ||
 577                  newDesc.type() == PropertyDescriptor.GENERIC)) {
 578             if (!currentDesc.isConfigurable() && !currentDesc.isWritable()) {
 579                 if (newDesc.has(WRITABLE) && newDesc.isWritable() ||
 580                     newDesc.has(VALUE) && !ScriptRuntime.sameValue(currentDesc.getValue(), newDesc.getValue())) {
 581                     if (reject) {
 582                         throw typeError(global, "cant.redefine.property", name, ScriptRuntime.safeToString(this));
 583                     }
 584                     return false;
 585                 }
 586             }
 587 
 588             final boolean newValue = newDesc.has(VALUE);
 589             final Object value     = newValue ? newDesc.getValue() : currentDesc.getValue();
 590 
 591             if (newValue && property != null) {
 592                 // Temporarily clear flags.
 593                 property = modifyOwnProperty(property, 0);
 594                 set(key, value, false);
 595                 //this might change the map if we change types of the property
 596                 //hence we need to read it again. note that we should probably
 597                 //have the setter return the new property throughout and in
 598                 //general respect Property return values from modify and add
 599                 //functions - which we don't seem to do at all here :-(
 600                 //There is already a bug filed to generify PropertyAccess so we
 601                 //can have the setter return e.g. a Property
 602                 property = getMap().findProperty(key);
 603             }
 604 
 605             if (property == null) {
 606                 // promoting an arrayData value to actual property
 607                 addOwnProperty(key, propFlags, value);
 608                 checkIntegerKey(key);
 609             } else {
 610                 // Now set the new flags
 611                 modifyOwnProperty(property, propFlags);
 612             }
 613         } else if (currentDesc.type() == PropertyDescriptor.ACCESSOR &&
 614                    (newDesc.type() == PropertyDescriptor.ACCESSOR ||
 615                     newDesc.type() == PropertyDescriptor.GENERIC)) {
 616             if (!currentDesc.isConfigurable()) {
 617                 if (newDesc.has(PropertyDescriptor.GET) && !ScriptRuntime.sameValue(currentDesc.getGetter(), newDesc.getGetter()) ||
 618                     newDesc.has(PropertyDescriptor.SET) && !ScriptRuntime.sameValue(currentDesc.getSetter(), newDesc.getSetter())) {
 619                     if (reject) {
 620                         throw typeError(global, "cant.redefine.property", name, ScriptRuntime.safeToString(this));
 621                     }
 622                     return false;
 623                 }
 624             }
 625             // New set the new features.
 626             modifyOwnProperty(property, propFlags,
 627                                       newDesc.has(GET) ? newDesc.getGetter() : currentDesc.getGetter(),
 628                                       newDesc.has(SET) ? newDesc.getSetter() : currentDesc.getSetter());
 629         } else {
 630             // changing descriptor type
 631             if (!currentDesc.isConfigurable()) {
 632                 // not configurable can not be made configurable
 633                 if (reject) {
 634                     throw typeError(global, "cant.redefine.property", name, ScriptRuntime.safeToString(this));
 635                 }
 636                 return false;
 637             }
 638 
 639             propFlags = 0;
 640 
 641             // Preserve only configurable and enumerable from current desc
 642             // if those are not overridden in the new property descriptor.
 643             boolean value = newDesc.has(CONFIGURABLE) ? newDesc.isConfigurable() : currentDesc.isConfigurable();
 644             if (!value) {
 645                 propFlags |= Property.NOT_CONFIGURABLE;
 646             }
 647             value = newDesc.has(ENUMERABLE)? newDesc.isEnumerable() : currentDesc.isEnumerable();
 648             if (!value) {
 649                 propFlags |= Property.NOT_ENUMERABLE;
 650             }
 651 
 652             final int type = newDesc.type();
 653             if (type == PropertyDescriptor.DATA) {
 654                 // get writable from the new descriptor
 655                 value = newDesc.has(WRITABLE) && newDesc.isWritable();
 656                 if (!value) {
 657                     propFlags |= Property.NOT_WRITABLE;
 658                 }
 659 
 660                 // delete the old property
 661                 deleteOwnProperty(property);
 662                 // add new data property
 663                 addOwnProperty(key, propFlags, newDesc.getValue());
 664             } else if (type == PropertyDescriptor.ACCESSOR) {
 665                 if (property == null) {
 666                     addOwnProperty(key, propFlags,
 667                                      newDesc.has(GET) ? newDesc.getGetter() : null,
 668                                      newDesc.has(SET) ? newDesc.getSetter() : null);
 669                 } else {
 670                     // Modify old property with the new features.
 671                     modifyOwnProperty(property, propFlags,
 672                                         newDesc.has(GET) ? newDesc.getGetter() : null,
 673                                         newDesc.has(SET) ? newDesc.getSetter() : null);
 674                 }
 675             }
 676         }
 677 
 678         checkIntegerKey(key);
 679 
 680         return true;
 681     }
 682 
 683     /**
 684      * Almost like defineOwnProperty(int,Object) for arrays this one does
 685      * not add 'gap' elements (like the array one does).
 686      *
 687      * @param index key for property
 688      * @param value value to define
 689      */
 690     public void defineOwnProperty(final int index, final Object value) {
 691         assert isValidArrayIndex(index) : "invalid array index";
 692         final long longIndex = ArrayIndex.toLongIndex(index);
 693         doesNotHaveEnsureDelete(longIndex, getArray().length(), false);
 694         setArray(getArray().set(index, value, false));
 695     }
 696 
 697     private void checkIntegerKey(final String key) {
 698         final int index = getArrayIndex(key);
 699 
 700         if (isValidArrayIndex(index)) {
 701             final ArrayData data = getArray();
 702 
 703             if (data.has(index)) {
 704                 setArray(data.delete(index));
 705             }
 706         }
 707     }
 708 
 709     /**
 710       * Add a new property to the object.
 711       *
 712       * @param key          property key
 713       * @param propertyDesc property descriptor for property
 714       */
 715     public final void addOwnProperty(final String key, final PropertyDescriptor propertyDesc) {
 716         // Already checked that there is no own property with that key.
 717         PropertyDescriptor pdesc = propertyDesc;
 718 
 719         final int propFlags = Property.toFlags(pdesc);
 720 
 721         if (pdesc.type() == PropertyDescriptor.GENERIC) {
 722             final Global global = Context.getGlobal();
 723             final PropertyDescriptor dDesc = global.newDataDescriptor(UNDEFINED, false, false, false);
 724 
 725             dDesc.fillFrom((ScriptObject)pdesc);
 726             pdesc = dDesc;
 727         }
 728 
 729         final int type = pdesc.type();
 730         if (type == PropertyDescriptor.DATA) {
 731             addOwnProperty(key, propFlags, pdesc.getValue());
 732         } else if (type == PropertyDescriptor.ACCESSOR) {
 733             addOwnProperty(key, propFlags,
 734                     pdesc.has(GET) ? pdesc.getGetter() : null,
 735                     pdesc.has(SET) ? pdesc.getSetter() : null);
 736         }
 737 
 738         checkIntegerKey(key);
 739     }
 740 
 741     /**
 742      * Low level property API (not using property descriptors)
 743      * <p>
 744      * Find a property in the prototype hierarchy. Note: this is final and not
 745      * a good idea to override. If you have to, use
 746      * {jdk.nashorn.internal.objects.NativeArray{@link #getProperty(String)} or
 747      * {jdk.nashorn.internal.objects.NativeArray{@link #getPropertyDescriptor(String)} as the
 748      * overriding way to find array properties
 749      *
 750      * @see jdk.nashorn.internal.objects.NativeArray
 751      *
 752      * @param key  Property key.
 753      * @param deep Whether the search should look up proto chain.
 754      *
 755      * @return FindPropertyData or null if not found.
 756      */
 757     public final FindProperty findProperty(final String key, final boolean deep) {
 758         return findProperty(key, deep, false, this);
 759     }
 760 
 761     /**
 762      * Low level property API (not using property descriptors)
 763      * <p>
 764      * Find a property in the prototype hierarchy. Note: this is not a good idea
 765      * to override except as it was done in {@link WithObject}.
 766      * If you have to, use
 767      * {jdk.nashorn.internal.objects.NativeArray{@link #getProperty(String)} or
 768      * {jdk.nashorn.internal.objects.NativeArray{@link #getPropertyDescriptor(String)} as the
 769      * overriding way to find array properties
 770      *
 771      * @see jdk.nashorn.internal.objects.NativeArray
 772      *
 773      * @param key  Property key.
 774      * @param deep Whether the search should look up proto chain.
 775      * @param stopOnNonScope should a deep search stop on the first non-scope object?
 776      * @param start the object on which the lookup was originally initiated
 777      *
 778      * @return FindPropertyData or null if not found.
 779      */
 780     FindProperty findProperty(final String key, final boolean deep, final boolean stopOnNonScope, final ScriptObject start) {
 781         // if doing deep search, stop search on the first non-scope object if asked to do so
 782         if (stopOnNonScope && start != this && !isScope()) {
 783             return null;
 784         }
 785 
 786         final PropertyMap selfMap  = getMap();
 787         final Property    property = selfMap.findProperty(key);
 788 
 789         if (property != null) {
 790             return new FindProperty(start, this, property);
 791         }
 792 
 793         if (deep) {
 794             final ScriptObject myProto = getProto();
 795             if (myProto != null) {
 796                 return myProto.findProperty(key, deep, stopOnNonScope, start);
 797             }
 798         }
 799 
 800         return null;
 801     }
 802 
 803     /**
 804      * Low level property API. This is similar to {@link #findProperty(String, boolean)} but returns a
 805      * {@code boolean} value instead of a {@link FindProperty} object.
 806      * @param key  Property key.
 807      * @param deep Whether the search should look up proto chain.
 808      * @return true if the property was found.
 809      */
 810     boolean hasProperty(final String key, final boolean deep) {
 811         if (getMap().findProperty(key) != null) {
 812             return true;
 813         }
 814 
 815         if (deep) {
 816             final ScriptObject myProto = getProto();
 817             if (myProto != null) {
 818                 return myProto.hasProperty(key, deep);
 819             }
 820         }
 821 
 822         return false;
 823     }
 824 
 825     /**
 826      * Add a new property to the object.
 827      * <p>
 828      * This a more "low level" way that doesn't involve {@link PropertyDescriptor}s
 829      *
 830      * @param key             Property key.
 831      * @param propertyFlags   Property flags.
 832      * @param getter          Property getter, or null if not defined
 833      * @param setter          Property setter, or null if not defined
 834      *
 835      * @return New property.
 836      */
 837     public final Property addOwnProperty(final String key, final int propertyFlags, final ScriptFunction getter, final ScriptFunction setter) {
 838         return addOwnProperty(newUserAccessors(key, propertyFlags, getter, setter));
 839     }
 840 
 841     /**
 842      * Add a new property to the object.
 843      * <p>
 844      * This a more "low level" way that doesn't involve {@link PropertyDescriptor}s
 845      *
 846      * @param key             Property key.
 847      * @param propertyFlags   Property flags.
 848      * @param value           Value of property
 849      *
 850      * @return New property.
 851      */
 852     public final Property addOwnProperty(final String key, final int propertyFlags, final Object value) {
 853         return addSpillProperty(key, propertyFlags, value, true);
 854     }
 855 
 856     /**
 857      * Add a new property to the object.
 858      * <p>
 859      * This a more "low level" way that doesn't involve {@link PropertyDescriptor}s
 860      *
 861      * @param newProperty property to add
 862      *
 863      * @return New property.
 864      */
 865     public final Property addOwnProperty(final Property newProperty) {
 866         PropertyMap oldMap = getMap();
 867         while (true) {
 868             final PropertyMap newMap = oldMap.addProperty(newProperty);
 869             if (!compareAndSetMap(oldMap, newMap)) {
 870                 oldMap = getMap();
 871                 final Property oldProperty = oldMap.findProperty(newProperty.getKey());
 872 
 873                 if (oldProperty != null) {
 874                     return oldProperty;
 875                 }
 876             } else {
 877                 return newProperty;
 878             }
 879         }
 880     }
 881 
 882     private void erasePropertyValue(final Property property) {
 883         // Erase the property field value with undefined. If the property is defined
 884         // by user-defined accessors, we don't want to call the setter!!
 885         if (!(property instanceof UserAccessorProperty)) {
 886             assert property != null;
 887             property.setValue(this, this, UNDEFINED, false);
 888         }
 889     }
 890 
 891     /**
 892      * Delete a property from the object.
 893      *
 894      * @param property Property to delete.
 895      *
 896      * @return true if deleted.
 897      */
 898     public final boolean deleteOwnProperty(final Property property) {
 899         erasePropertyValue(property);
 900         PropertyMap oldMap = getMap();
 901 
 902         while (true) {
 903             final PropertyMap newMap = oldMap.deleteProperty(property);
 904 
 905             if (newMap == null) {
 906                 return false;
 907             }
 908 
 909             if (!compareAndSetMap(oldMap, newMap)) {
 910                 oldMap = getMap();
 911             } else {
 912                 // delete getter and setter function references so that we don't leak
 913                 if (property instanceof UserAccessorProperty) {
 914                     ((UserAccessorProperty)property).setAccessors(this, getMap(), null);
 915                 }
 916                 Global.getConstants().delete(property.getKey());
 917                 return true;
 918             }
 919         }
 920 
 921     }
 922 
 923     /**
 924      * Fast initialization functions for ScriptFunctions that are strict, to avoid
 925      * creating setters that probably aren't used. Inject directly into the spill pool
 926      * the defaults for "arguments" and "caller"
 927      *
 928      * @param key
 929      * @param propertyFlags
 930      * @param getter
 931      * @param setter
 932      */
 933     protected final void initUserAccessors(final String key, final int propertyFlags, final ScriptFunction getter, final ScriptFunction setter) {
 934         final int slot = spillLength;
 935         ensureSpillSize(spillLength); //arguments=slot0, caller=slot0
 936         objectSpill[slot] = new UserAccessorProperty.Accessors(getter, setter);
 937         final PropertyMap oldMap = getMap();
 938         Property    newProperty;
 939         PropertyMap newMap;
 940         do {
 941             newProperty = new UserAccessorProperty(key, propertyFlags, slot);
 942             newMap = oldMap.addProperty(newProperty);
 943         } while (!compareAndSetMap(oldMap, newMap));
 944     }
 945 
 946     /**
 947      * Modify a property in the object
 948      *
 949      * @param oldProperty    property to modify
 950      * @param propertyFlags  new property flags
 951      * @param getter         getter for {@link UserAccessorProperty}, null if not present or N/A
 952      * @param setter         setter for {@link UserAccessorProperty}, null if not present or N/A
 953      *
 954      * @return new property
 955      */
 956     public final Property modifyOwnProperty(final Property oldProperty, final int propertyFlags, final ScriptFunction getter, final ScriptFunction setter) {
 957         Property newProperty;
 958 
 959         if (oldProperty instanceof UserAccessorProperty) {
 960             final UserAccessorProperty uc = (UserAccessorProperty)oldProperty;
 961             final int slot = uc.getSlot();
 962 
 963             assert uc.getCurrentType() == Object.class;
 964             if (slot >= spillLength) {
 965                 uc.setAccessors(this, getMap(), new UserAccessorProperty.Accessors(getter, setter));
 966             } else {
 967                 final UserAccessorProperty.Accessors gs = uc.getAccessors(this); //this crashes
 968                 if (gs == null) {
 969                     uc.setAccessors(this, getMap(), new UserAccessorProperty.Accessors(getter, setter));
 970                 } else {
 971                     //reuse existing getter setter for speed
 972                     gs.set(getter, setter);
 973                     if (uc.getFlags() == propertyFlags) {
 974                         return oldProperty;
 975                     }
 976                 }
 977             }
 978             newProperty = new UserAccessorProperty(uc.getKey(), propertyFlags, slot);
 979         } else {
 980             // erase old property value and create new user accessor property
 981             erasePropertyValue(oldProperty);
 982             newProperty = newUserAccessors(oldProperty.getKey(), propertyFlags, getter, setter);
 983         }
 984 
 985         return modifyOwnProperty(oldProperty, newProperty);
 986     }
 987 
 988     /**
 989       * Modify a property in the object
 990       *
 991       * @param oldProperty    property to modify
 992       * @param propertyFlags  new property flags
 993       *
 994       * @return new property
 995       */
 996     public final Property modifyOwnProperty(final Property oldProperty, final int propertyFlags) {
 997         return modifyOwnProperty(oldProperty, oldProperty.setFlags(propertyFlags));
 998     }
 999 
1000     /**
1001      * Modify a property in the object, replacing a property with a new one
1002      *
1003      * @param oldProperty   property to replace
1004      * @param newProperty   property to replace it with
1005      *
1006      * @return new property
1007      */
1008     private Property modifyOwnProperty(final Property oldProperty, final Property newProperty) {
1009         if (oldProperty == newProperty) {
1010             return newProperty; //nop
1011         }
1012 
1013         assert newProperty.getKey().equals(oldProperty.getKey()) : "replacing property with different key";
1014 
1015         PropertyMap oldMap = getMap();
1016 
1017         while (true) {
1018             final PropertyMap newMap = oldMap.replaceProperty(oldProperty, newProperty);
1019 
1020             if (!compareAndSetMap(oldMap, newMap)) {
1021                 oldMap = getMap();
1022                 final Property oldPropertyLookup = oldMap.findProperty(oldProperty.getKey());
1023 
1024                 if (oldPropertyLookup != null && oldPropertyLookup.equals(newProperty)) {
1025                     return oldPropertyLookup;
1026                 }
1027             } else {
1028                 return newProperty;
1029             }
1030         }
1031     }
1032 
1033     /**
1034      * Update getter and setter in an object literal.
1035      *
1036      * @param key    Property key.
1037      * @param getter {@link UserAccessorProperty} defined getter, or null if none
1038      * @param setter {@link UserAccessorProperty} defined setter, or null if none
1039      */
1040     public final void setUserAccessors(final String key, final ScriptFunction getter, final ScriptFunction setter) {
1041         final Property oldProperty = getMap().findProperty(key);
1042         if (oldProperty instanceof UserAccessorProperty) {
1043             modifyOwnProperty(oldProperty, oldProperty.getFlags(), getter, setter);
1044         } else {
1045             addOwnProperty(newUserAccessors(key, oldProperty != null ? oldProperty.getFlags() : 0, getter, setter));
1046         }
1047     }
1048 
1049     private static int getIntValue(final FindProperty find, final int programPoint) {
1050         final MethodHandle getter = find.getGetter(int.class, programPoint);
1051         if (getter != null) {
1052             try {
1053                 return (int)getter.invokeExact((Object)find.getGetterReceiver());
1054             } catch (final Error|RuntimeException e) {
1055                 throw e;
1056             } catch (final Throwable e) {
1057                 throw new RuntimeException(e);
1058             }
1059         }
1060 
1061         return UNDEFINED_INT;
1062     }
1063 
1064     private static long getLongValue(final FindProperty find, final int programPoint) {
1065         final MethodHandle getter = find.getGetter(long.class, programPoint);
1066         if (getter != null) {
1067             try {
1068                 return (long)getter.invokeExact((Object)find.getGetterReceiver());
1069             } catch (final Error|RuntimeException e) {
1070                 throw e;
1071             } catch (final Throwable e) {
1072                 throw new RuntimeException(e);
1073             }
1074         }
1075 
1076         return UNDEFINED_LONG;
1077     }
1078 
1079     private static double getDoubleValue(final FindProperty find, final int programPoint) {
1080         final MethodHandle getter = find.getGetter(double.class, programPoint);
1081         if (getter != null) {
1082             try {
1083                 return (double)getter.invokeExact((Object)find.getGetterReceiver());
1084             } catch (final Error|RuntimeException e) {
1085                 throw e;
1086             } catch (final Throwable e) {
1087                 throw new RuntimeException(e);
1088             }
1089         }
1090 
1091         return UNDEFINED_DOUBLE;
1092     }
1093 
1094     /**
1095      * Return methodHandle of value function for call.
1096      *
1097      * @param find      data from find property.
1098      * @param type      method type of function.
1099      * @param bindName  null or name to bind to second argument (property not found method.)
1100      *
1101      * @return value of property as a MethodHandle or null.
1102      */
1103     protected MethodHandle getCallMethodHandle(final FindProperty find, final MethodType type, final String bindName) {
1104         return getCallMethodHandle(find.getObjectValue(), type, bindName);
1105     }
1106 
1107     /**
1108      * Return methodHandle of value function for call.
1109      *
1110      * @param value     value of receiver, it not a {@link ScriptFunction} this will return null.
1111      * @param type      method type of function.
1112      * @param bindName  null or name to bind to second argument (property not found method.)
1113      *
1114      * @return value of property as a MethodHandle or null.
1115      */
1116     protected static MethodHandle getCallMethodHandle(final Object value, final MethodType type, final String bindName) {
1117         return value instanceof ScriptFunction ? ((ScriptFunction)value).getCallMethodHandle(type, bindName) : null;
1118     }
1119 
1120     /**
1121      * Get value using found property.
1122      *
1123      * @param property Found property.
1124      *
1125      * @return Value of property.
1126      */
1127     public final Object getWithProperty(final Property property) {
1128         return new FindProperty(this, this, property).getObjectValue();
1129     }
1130 
1131     /**
1132      * Get a property given a key
1133      *
1134      * @param key property key
1135      *
1136      * @return property for key
1137      */
1138     public final Property getProperty(final String key) {
1139         return getMap().findProperty(key);
1140     }
1141 
1142     /**
1143      * Overridden by {@link jdk.nashorn.internal.objects.NativeArguments} class (internal use.)
1144      * Used for argument access in a vararg function using parameter name.
1145      * Returns the argument at a given key (index)
1146      *
1147      * @param key argument index
1148      *
1149      * @return the argument at the given position, or undefined if not present
1150      */
1151     public Object getArgument(final int key) {
1152         return get(key);
1153     }
1154 
1155     /**
1156      * Overridden by {@link jdk.nashorn.internal.objects.NativeArguments} class (internal use.)
1157      * Used for argument access in a vararg function using parameter name.
1158      * Returns the argument at a given key (index)
1159      *
1160      * @param key   argument index
1161      * @param value the value to write at the given index
1162      */
1163     public void setArgument(final int key, final Object value) {
1164         set(key, value, false);
1165     }
1166 
1167     /**
1168      * Return the current context from the object's map.
1169      * @return Current context.
1170      */
1171     protected Context getContext() {
1172         return Context.fromClass(getClass());
1173     }
1174 
1175     /**
1176      * Return the map of an object.
1177      * @return PropertyMap object.
1178      */
1179     public final PropertyMap getMap() {
1180         return map;
1181     }
1182 
1183     /**
1184      * Set the initial map.
1185      * @param map Initial map.
1186      */
1187     public final void setMap(final PropertyMap map) {
1188         this.map = map;
1189     }
1190 
1191     /**
1192      * Conditionally set the new map if the old map is the same.
1193      * @param oldMap Map prior to manipulation.
1194      * @param newMap Replacement map.
1195      * @return true if the operation succeeded.
1196      */
1197     protected final boolean compareAndSetMap(final PropertyMap oldMap, final PropertyMap newMap) {
1198         if (oldMap == this.map) {
1199             this.map = newMap;
1200             return true;
1201         }
1202         return false;
1203      }
1204 
1205     /**
1206      * Return the __proto__ of an object.
1207      * @return __proto__ object.
1208      */
1209     public final ScriptObject getProto() {
1210         return proto;
1211     }
1212 
1213     /**
1214      * Get the proto of a specific depth
1215      * @param n depth
1216      * @return proto at given depth
1217      */
1218     public final ScriptObject getProto(final int n) {
1219         assert n > 0;
1220         ScriptObject p = getProto();
1221         for (int i = n; i-- > 0;) {
1222             p = p.getProto();
1223         }
1224         return p;
1225     }
1226 
1227     /**
1228      * Set the __proto__ of an object.
1229      * @param newProto new __proto__ to set.
1230      */
1231     public final void setProto(final ScriptObject newProto) {
1232         final ScriptObject oldProto = proto;
1233 
1234         if (oldProto != newProto) {
1235             proto = newProto;
1236 
1237             // Let current listeners know that the protototype has changed and set our map
1238             final PropertyListeners listeners = getMap().getListeners();
1239             if (listeners != null) {
1240                 listeners.protoChanged();
1241             }
1242             // Replace our current allocator map with one that is associated with the new prototype.
1243             setMap(getMap().changeProto(newProto));
1244         }
1245     }
1246 
1247     /**
1248      * Set the initial __proto__ of this object. This should be used instead of
1249      * {@link #setProto} if it is known that the current property map will not be
1250      * used on a new object with any other parent property map, so we can pass over
1251      * property map invalidation/evolution.
1252      *
1253      * @param initialProto the initial __proto__ to set.
1254      */
1255     public void setInitialProto(final ScriptObject initialProto) {
1256         this.proto = initialProto;
1257     }
1258 
1259     /**
1260      * Invoked from generated bytecode to initialize the prototype of object literals to the global Object prototype.
1261      * @param obj the object literal that needs to have its prototype initialized to the global Object prototype.
1262      */
1263     public static void setGlobalObjectProto(final ScriptObject obj) {
1264         obj.setInitialProto(Global.objectPrototype());
1265     }
1266 
1267     /**
1268      * Set the __proto__ of an object with checks.
1269      * This is the built-in operation [[SetPrototypeOf]]
1270      * See ES6 draft spec: 9.1.2 [[SetPrototypeOf]] (V)
1271      *
1272      * @param newProto Prototype to set.
1273      */
1274     public final void setPrototypeOf(final Object newProto) {
1275         if (newProto == null || newProto instanceof ScriptObject) {
1276             if (! isExtensible()) {
1277                 // okay to set same proto again - even if non-extensible
1278 
1279                 if (newProto == getProto()) {
1280                     return;
1281                 }
1282                 throw typeError("__proto__.set.non.extensible", ScriptRuntime.safeToString(this));
1283             }
1284 
1285             // check for circularity
1286             ScriptObject p = (ScriptObject)newProto;
1287             while (p != null) {
1288                 if (p == this) {
1289                     throw typeError("circular.__proto__.set", ScriptRuntime.safeToString(this));
1290                 }
1291                 p = p.getProto();
1292             }
1293             setProto((ScriptObject)newProto);
1294         } else {
1295             throw typeError("cant.set.proto.to.non.object", ScriptRuntime.safeToString(this), ScriptRuntime.safeToString(newProto));
1296         }
1297     }
1298 
1299     /**
1300      * Set the __proto__ of an object from an object literal.
1301      * See ES6 draft spec: B.3.1 __proto__ Property Names in
1302      * Object Initializers. Step 6 handling of "__proto__".
1303      *
1304      * @param newProto Prototype to set.
1305      */
1306     public final void setProtoFromLiteral(final Object newProto) {
1307         if (newProto == null || newProto instanceof ScriptObject) {
1308             setPrototypeOf(newProto);
1309         } else {
1310             // Some non-object, non-null. Then, we need to set
1311             // Object.prototype as the new __proto__
1312             //
1313             // var obj = { __proto__ : 34 };
1314             // print(obj.__proto__ === Object.prototype); // => true
1315             setPrototypeOf(Global.objectPrototype());
1316         }
1317     }
1318 
1319     /**
1320      * return an array of own property keys associated with the object.
1321      *
1322      * @param all True if to include non-enumerable keys.
1323      * @return Array of keys.
1324      */
1325     public String[] getOwnKeys(final boolean all) {
1326         final List<Object> keys    = new ArrayList<>();
1327         final PropertyMap  selfMap = this.getMap();
1328 
1329         final ArrayData array  = getArray();
1330         final long length      = array.length();
1331 
1332         for (long i = 0; i < length; i = array.nextIndex(i)) {
1333             if (array.has((int)i)) {
1334                 keys.add(JSType.toString(i));
1335             }
1336         }
1337 
1338         for (final Property property : selfMap.getProperties()) {
1339             if (all || property.isEnumerable()) {
1340                 keys.add(property.getKey());
1341             }
1342         }
1343 
1344         return keys.toArray(new String[keys.size()]);
1345     }
1346 
1347     /**
1348      * Check if this ScriptObject has array entries. This means that someone has
1349      * set values with numeric keys in the object.
1350      *
1351      * @return true if array entries exists.
1352      */
1353     public boolean hasArrayEntries() {
1354         return getArray().length() > 0 || getMap().containsArrayKeys();
1355     }
1356 
1357     /**
1358      * Return the valid JavaScript type name descriptor
1359      *
1360      * @return "Object"
1361      */
1362     public String getClassName() {
1363         return "Object";
1364     }
1365 
1366     /**
1367      * {@code length} is a well known property. This is its getter.
1368      * Note that this *may* be optimized by other classes
1369      *
1370      * @return length property value for this ScriptObject
1371      */
1372     public Object getLength() {
1373         return get("length");
1374     }
1375 
1376     /**
1377      * Stateless toString for ScriptObjects.
1378      *
1379      * @return string description of this object, e.g. {@code [object Object]}
1380      */
1381     public String safeToString() {
1382         return "[object " + getClassName() + "]";
1383     }
1384 
1385     /**
1386      * Return the default value of the object with a given preferred type hint.
1387      * The preferred type hints are String.class for type String, Number.class
1388      * for type Number. <p>
1389      *
1390      * A <code>hint</code> of null means "no hint".
1391      *
1392      * ECMA 8.12.8 [[DefaultValue]](hint)
1393      *
1394      * @param typeHint the preferred type hint
1395      * @return the default value
1396      */
1397     public Object getDefaultValue(final Class<?> typeHint) {
1398         // We delegate to Global, as the implementation uses dynamic call sites to invoke object's "toString" and
1399         // "valueOf" methods, and in order to avoid those call sites from becoming megamorphic when multiple contexts
1400         // are being executed in a long-running program, we move the code and their associated dynamic call sites
1401         // (Global.TO_STRING and Global.VALUE_OF) into per-context code.
1402         return Context.getGlobal().getDefaultValue(this, typeHint);
1403     }
1404 
1405     /**
1406      * Checking whether a script object is an instance of another. Used
1407      * in {@link ScriptFunction} for hasInstance implementation, walks
1408      * the proto chain
1409      *
1410      * @param instance instace to check
1411      * @return true if 'instance' is an instance of this object
1412      */
1413     public boolean isInstance(final ScriptObject instance) {
1414         return false;
1415     }
1416 
1417     /**
1418      * Flag this ScriptObject as non extensible
1419      *
1420      * @return the object after being made non extensible
1421      */
1422     public ScriptObject preventExtensions() {
1423         PropertyMap oldMap = getMap();
1424         while (!compareAndSetMap(oldMap,  getMap().preventExtensions())) {
1425             oldMap = getMap();
1426         }
1427 
1428         //invalidate any fast array setters
1429         final ArrayData array = getArray();
1430         if (array != null) {
1431             array.invalidateSetters();
1432         }
1433         return this;
1434     }
1435 
1436     /**
1437      * Check whether if an Object (not just a ScriptObject) represents JavaScript array
1438      *
1439      * @param obj object to check
1440      *
1441      * @return true if array
1442      */
1443     public static boolean isArray(final Object obj) {
1444         return obj instanceof ScriptObject && ((ScriptObject)obj).isArray();
1445     }
1446 
1447     /**
1448      * Check if this ScriptObject is an array
1449      * @return true if array
1450      */
1451     public final boolean isArray() {
1452         return (flags & IS_ARRAY) != 0;
1453     }
1454 
1455     /**
1456      * Flag this ScriptObject as being an array
1457      */
1458     public final void setIsArray() {
1459         flags |= IS_ARRAY;
1460     }
1461 
1462     /**
1463      * Check if this ScriptObject is an {@code arguments} vector
1464      * @return true if arguments vector
1465      */
1466     public final boolean isArguments() {
1467         return (flags & IS_ARGUMENTS) != 0;
1468     }
1469 
1470     /**
1471      * Flag this ScriptObject as being an {@code arguments} vector
1472      */
1473     public final void setIsArguments() {
1474         flags |= IS_ARGUMENTS;
1475     }
1476 
1477     /**
1478      * Check if this object has non-writable length property
1479      *
1480      * @return {@code true} if 'length' property is non-writable
1481      */
1482     public final boolean isLengthNotWritable() {
1483         return (flags & IS_LENGTH_NOT_WRITABLE) != 0;
1484     }
1485 
1486     /**
1487      * Flag this object as having non-writable length property
1488      */
1489     public void setIsLengthNotWritable() {
1490         flags |= IS_LENGTH_NOT_WRITABLE;
1491     }
1492 
1493     /**
1494      * Get the {@link ArrayData} for this ScriptObject if it is an array
1495      * @return array data
1496      */
1497     public final ArrayData getArray() {
1498         return arrayData;
1499     }
1500 
1501     /**
1502      * Set the {@link ArrayData} for this ScriptObject if it is to be an array
1503      * @param arrayData the array data
1504      */
1505     public final void setArray(final ArrayData arrayData) {
1506         this.arrayData = arrayData;
1507     }
1508 
1509     /**
1510      * Check if this ScriptObject is extensible
1511      * @return true if extensible
1512      */
1513     public boolean isExtensible() {
1514         return getMap().isExtensible();
1515     }
1516 
1517     /**
1518      * ECMAScript 15.2.3.8 - seal implementation
1519      * @return the sealed ScriptObject
1520      */
1521     public ScriptObject seal() {
1522         PropertyMap oldMap = getMap();
1523 
1524         while (true) {
1525             final PropertyMap newMap = getMap().seal();
1526 
1527             if (!compareAndSetMap(oldMap, newMap)) {
1528                 oldMap = getMap();
1529             } else {
1530                 setArray(ArrayData.seal(getArray()));
1531                 return this;
1532             }
1533         }
1534     }
1535 
1536     /**
1537      * Check whether this ScriptObject is sealed
1538      * @return true if sealed
1539      */
1540     public boolean isSealed() {
1541         return getMap().isSealed();
1542     }
1543 
1544     /**
1545      * ECMA 15.2.39 - freeze implementation. Freeze this ScriptObject
1546      * @return the frozen ScriptObject
1547      */
1548     public ScriptObject freeze() {
1549         PropertyMap oldMap = getMap();
1550 
1551         while (true) {
1552             final PropertyMap newMap = getMap().freeze();
1553 
1554             if (!compareAndSetMap(oldMap, newMap)) {
1555                 oldMap = getMap();
1556             } else {
1557                 setArray(ArrayData.freeze(getArray()));
1558                 return this;
1559             }
1560         }
1561     }
1562 
1563     /**
1564      * Check whether this ScriptObject is frozen
1565      * @return true if frozen
1566      */
1567     public boolean isFrozen() {
1568         return getMap().isFrozen();
1569     }
1570 
1571 
1572     /**
1573      * Flag this ScriptObject as scope
1574      */
1575     public final void setIsScope() {
1576         if (Context.DEBUG) {
1577             scopeCount++;
1578         }
1579         flags |= IS_SCOPE;
1580     }
1581 
1582     /**
1583      * Check whether this ScriptObject is scope
1584      * @return true if scope
1585      */
1586     public final boolean isScope() {
1587         return (flags & IS_SCOPE) != 0;
1588     }
1589 
1590     /**
1591      * Tag this script object as built in
1592      */
1593     public final void setIsBuiltin() {
1594         flags |= IS_BUILTIN;
1595     }
1596 
1597     /**
1598      * Check if this script object is built in
1599      * @return true if build in
1600      */
1601     public final boolean isBuiltin() {
1602         return (flags & IS_BUILTIN) != 0;
1603     }
1604 
1605     /**
1606      * Clears the properties from a ScriptObject
1607      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1608      *
1609      * @param strict strict mode or not
1610      */
1611     public void clear(final boolean strict) {
1612         final Iterator<String> iter = propertyIterator();
1613         while (iter.hasNext()) {
1614             delete(iter.next(), strict);
1615         }
1616     }
1617 
1618     /**
1619      * Checks if a property with a given key is present in a ScriptObject
1620      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1621      *
1622      * @param key the key to check for
1623      * @return true if a property with the given key exists, false otherwise
1624      */
1625     public boolean containsKey(final Object key) {
1626         return has(key);
1627     }
1628 
1629     /**
1630      * Checks if a property with a given value is present in a ScriptObject
1631      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1632      *
1633      * @param value value to check for
1634      * @return true if a property with the given value exists, false otherwise
1635      */
1636     public boolean containsValue(final Object value) {
1637         final Iterator<Object> iter = valueIterator();
1638         while (iter.hasNext()) {
1639             if (iter.next().equals(value)) {
1640                 return true;
1641             }
1642         }
1643         return false;
1644     }
1645 
1646     /**
1647      * Returns the set of {@literal <property, value>} entries that make up this
1648      * ScriptObject's properties
1649      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1650      *
1651      * @return an entry set of all the properties in this object
1652      */
1653     public Set<Map.Entry<Object, Object>> entrySet() {
1654         final Iterator<String> iter = propertyIterator();
1655         final Set<Map.Entry<Object, Object>> entries = new HashSet<>();
1656         while (iter.hasNext()) {
1657             final Object key = iter.next();
1658             entries.add(new AbstractMap.SimpleImmutableEntry<>(key, get(key)));
1659         }
1660         return Collections.unmodifiableSet(entries);
1661     }
1662 
1663     /**
1664      * Check whether a ScriptObject contains no properties
1665      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1666      *
1667      * @return true if object has no properties
1668      */
1669     public boolean isEmpty() {
1670         return !propertyIterator().hasNext();
1671     }
1672 
1673     /**
1674      * Return the set of keys (property names) for all properties
1675      * in this ScriptObject
1676      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1677      *
1678      * @return keySet of this ScriptObject
1679      */
1680     public Set<Object> keySet() {
1681         final Iterator<String> iter = propertyIterator();
1682         final Set<Object> keySet = new HashSet<>();
1683         while (iter.hasNext()) {
1684             keySet.add(iter.next());
1685         }
1686         return Collections.unmodifiableSet(keySet);
1687     }
1688 
1689     /**
1690      * Put a property in the ScriptObject
1691      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1692      *
1693      * @param key property key
1694      * @param value property value
1695      * @param strict strict mode or not
1696      * @return oldValue if property with same key existed already
1697      */
1698     public Object put(final Object key, final Object value, final boolean strict) {
1699         final Object oldValue = get(key);
1700         set(key, value, strict);
1701         return oldValue;
1702     }
1703 
1704     /**
1705      * Put several properties in the ScriptObject given a mapping
1706      * of their keys to their values
1707      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1708      *
1709      * @param otherMap a {@literal <key,value>} map of properties to add
1710      * @param strict strict mode or not
1711      */
1712     public void putAll(final Map<?, ?> otherMap, final boolean strict) {
1713         for (final Map.Entry<?, ?> entry : otherMap.entrySet()) {
1714             set(entry.getKey(), entry.getValue(), strict);
1715         }
1716     }
1717 
1718     /**
1719      * Remove a property from the ScriptObject.
1720      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1721      *
1722      * @param key the key of the property
1723      * @param strict strict mode or not
1724      * @return the oldValue of the removed property
1725      */
1726     public Object remove(final Object key, final boolean strict) {
1727         final Object oldValue = get(key);
1728         delete(key, strict);
1729         return oldValue;
1730     }
1731 
1732     /**
1733      * Return the size of the ScriptObject - i.e. the number of properties
1734      * it contains
1735      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1736      *
1737      * @return number of properties in ScriptObject
1738      */
1739     public int size() {
1740         int n = 0;
1741         for (final Iterator<String> iter = propertyIterator(); iter.hasNext(); iter.next()) {
1742             n++;
1743         }
1744         return n;
1745     }
1746 
1747     /**
1748      * Return the values of the properties in the ScriptObject
1749      * (java.util.Map-like method to help ScriptObjectMirror implementation)
1750      *
1751      * @return collection of values for the properties in this ScriptObject
1752      */
1753     public Collection<Object> values() {
1754         final List<Object>     values = new ArrayList<>(size());
1755         final Iterator<Object> iter   = valueIterator();
1756         while (iter.hasNext()) {
1757             values.add(iter.next());
1758         }
1759         return Collections.unmodifiableList(values);
1760     }
1761 
1762     /**
1763      * Lookup method that, given a CallSiteDescriptor, looks up the target
1764      * MethodHandle and creates a GuardedInvocation
1765      * with the appropriate guard(s).
1766      *
1767      * @param desc call site descriptor
1768      * @param request the link request
1769      *
1770      * @return GuardedInvocation for the callsite
1771      */
1772     public GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request) {
1773         final int c = desc.getNameTokenCount();
1774         // JavaScript is "immune" to all currently defined Dynalink composite operation - getProp is the same as getElem
1775         // is the same as getMethod as JavaScript objects have a single namespace for all three. Therefore, we don't
1776         // care about them, and just link to whatever is the first operation.
1777         final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
1778         // NOTE: we support getElem and setItem as JavaScript doesn't distinguish items from properties. Nashorn itself
1779         // emits "dyn:getProp:identifier" for "<expr>.<identifier>" and "dyn:getElem" for "<expr>[<expr>]", but we are
1780         // more flexible here and dispatch not on operation name (getProp vs. getElem), but rather on whether the
1781         // operation has an associated name or not.
1782         switch (operator) {
1783         case "getProp":
1784         case "getElem":
1785         case "getMethod":
1786             return c > 2 ? findGetMethod(desc, request, operator) : findGetIndexMethod(desc, request);
1787         case "setProp":
1788         case "setElem":
1789             return c > 2 ? findSetMethod(desc, request) : findSetIndexMethod(desc, request);
1790         case "call":
1791             return findCallMethod(desc, request);
1792         case "new":
1793             return findNewMethod(desc, request);
1794         case "callMethod":
1795             return findCallMethodMethod(desc, request);
1796         default:
1797             return null;
1798         }
1799     }
1800 
1801     /**
1802      * Find the appropriate New method for an invoke dynamic call.
1803      *
1804      * @param desc The invoke dynamic call site descriptor.
1805      * @param request The link request
1806      *
1807      * @return GuardedInvocation to be invoked at call site.
1808      */
1809     protected GuardedInvocation findNewMethod(final CallSiteDescriptor desc, final LinkRequest request) {
1810         return notAFunction();
1811     }
1812 
1813     /**
1814      * Find the appropriate CALL method for an invoke dynamic call.
1815      * This generates "not a function" always
1816      *
1817      * @param desc    the call site descriptor.
1818      * @param request the link request
1819      *
1820      * @return GuardedInvocation to be invoed at call site.
1821      */
1822     protected GuardedInvocation findCallMethod(final CallSiteDescriptor desc, final LinkRequest request) {
1823         return notAFunction();
1824     }
1825 
1826     private GuardedInvocation notAFunction() {
1827         throw typeError("not.a.function", ScriptRuntime.safeToString(this));
1828     }
1829 
1830     /**
1831      * Find an implementation for a "dyn:callMethod" operation. Note that Nashorn internally never uses
1832      * "dyn:callMethod", but instead always emits two call sites in bytecode, one for "dyn:getMethod", and then another
1833      * one for "dyn:call". Explicit support for "dyn:callMethod" is provided for the benefit of potential external
1834      * callers. The implementation itself actually folds a "dyn:getMethod" method handle into a "dyn:call" method handle.
1835      *
1836      * @param desc    the call site descriptor.
1837      * @param request the link request
1838      *
1839      * @return GuardedInvocation to be invoked at call site.
1840      */
1841     protected GuardedInvocation findCallMethodMethod(final CallSiteDescriptor desc, final LinkRequest request) {
1842         // R(P0, P1, ...)
1843         final MethodType callType = desc.getMethodType();
1844         // use type Object(P0) for the getter
1845         final CallSiteDescriptor getterType = desc.changeMethodType(MethodType.methodType(Object.class, callType.parameterType(0)));
1846         final GuardedInvocation getter = findGetMethod(getterType, request, "getMethod");
1847 
1848         // Object(P0) => Object(P0, P1, ...)
1849         final MethodHandle argDroppingGetter = MH.dropArguments(getter.getInvocation(), 1, callType.parameterList().subList(1, callType.parameterCount()));
1850         // R(Object, P0, P1, ...)
1851         final MethodHandle invoker = Bootstrap.createDynamicInvoker("dyn:call", callType.insertParameterTypes(0, argDroppingGetter.type().returnType()));
1852         // Fold Object(P0, P1, ...) into R(Object, P0, P1, ...) => R(P0, P1, ...)
1853         return getter.replaceMethods(MH.foldArguments(invoker, argDroppingGetter), getter.getGuard());
1854     }
1855 
1856     /**
1857      * Test whether this object contains in its prototype chain or is itself a with-object.
1858      * @return true if a with-object was found
1859      */
1860     final boolean hasWithScope() {
1861         if (isScope()) {
1862             for (ScriptObject obj = this; obj != null; obj = obj.getProto()) {
1863                 if (obj instanceof WithObject) {
1864                     return true;
1865                 }
1866             }
1867         }
1868         return false;
1869     }
1870 
1871     /**
1872      * Add a filter to the first argument of {@code methodHandle} that calls its {@link #getProto()} method
1873      * {@code depth} times.
1874      * @param methodHandle a method handle
1875      * @param depth        distance to target prototype
1876      * @return the filtered method handle
1877      */
1878     static MethodHandle addProtoFilter(final MethodHandle methodHandle, final int depth) {
1879         if (depth == 0) {
1880             return methodHandle;
1881         }
1882         final int listIndex = depth - 1; // We don't need 0-deep walker
1883         MethodHandle filter = listIndex < PROTO_FILTERS.size() ? PROTO_FILTERS.get(listIndex) : null;
1884 
1885         if (filter == null) {
1886             filter = addProtoFilter(GETPROTO, depth - 1);
1887             PROTO_FILTERS.add(null);
1888             PROTO_FILTERS.set(listIndex, filter);
1889         }
1890 
1891         return MH.filterArguments(methodHandle, 0, filter.asType(filter.type().changeReturnType(methodHandle.type().parameterType(0))));
1892     }
1893 
1894     //this will only return true if apply is still builtin
1895     private static SwitchPoint checkReservedName(final CallSiteDescriptor desc, final LinkRequest request) {
1896         final boolean isApplyToCall = NashornCallSiteDescriptor.isApplyToCall(desc);
1897         final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
1898         if ("apply".equals(name) && isApplyToCall && Global.instance().isSpecialNameValid(name)) {
1899             assert Global.instance().getChangeCallback("apply") == Global.instance().getChangeCallback("call");
1900             return Global.instance().getChangeCallback("apply");
1901         }
1902         return null;
1903     }
1904 
1905     /**
1906      * Find the appropriate GET method for an invoke dynamic call.
1907      *
1908      * @param desc     the call site descriptor
1909      * @param request  the link request
1910      * @param operator operator for get: getProp, getMethod, getElem etc
1911      *
1912      * @return GuardedInvocation to be invoked at call site.
1913      */
1914     protected GuardedInvocation findGetMethod(final CallSiteDescriptor desc, final LinkRequest request, final String operator) {
1915         final boolean explicitInstanceOfCheck = explicitInstanceOfCheck(desc, request);
1916         final String name;
1917         final SwitchPoint reservedNameSwitchPoint;
1918 
1919         reservedNameSwitchPoint = checkReservedName(desc, request);
1920         if (reservedNameSwitchPoint != null) {
1921             name = "call"; //turn apply into call, it is the builtin apply and has been modified to explode args
1922         } else {
1923             name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
1924         }
1925 
1926         if (request.isCallSiteUnstable() || hasWithScope()) {
1927             return findMegaMorphicGetMethod(desc, name, "getMethod".equals(operator));
1928         }
1929 
1930         final FindProperty find = findProperty(name, true);
1931         MethodHandle mh;
1932 
1933         if (find == null) {
1934             switch (operator) {
1935             case "getProp":
1936                 return noSuchProperty(desc, request);
1937             case "getMethod":
1938                 return noSuchMethod(desc, request);
1939             case "getElem":
1940                 return createEmptyGetter(desc, explicitInstanceOfCheck, name);
1941             default:
1942                 throw new AssertionError(operator); // never invoked with any other operation
1943             }
1944         }
1945 
1946         final GuardedInvocation cinv = Global.getConstants().findGetMethod(find, this, desc, request, operator);
1947         if (cinv != null) {
1948             return cinv;
1949         }
1950 
1951         final Class<?> returnType = desc.getMethodType().returnType();
1952         final Property property   = find.getProperty();
1953 
1954         final int programPoint = NashornCallSiteDescriptor.isOptimistic(desc) ?
1955                 NashornCallSiteDescriptor.getProgramPoint(desc) :
1956                 UnwarrantedOptimismException.INVALID_PROGRAM_POINT;
1957 
1958         mh = find.getGetter(returnType, programPoint);
1959         // Get the appropriate guard for this callsite and property.
1960         final MethodHandle guard = NashornGuards.getGuard(this, property, desc, explicitInstanceOfCheck);
1961         final ScriptObject owner = find.getOwner();
1962         final Class<ClassCastException> exception = explicitInstanceOfCheck ? null : ClassCastException.class;
1963 
1964         final SwitchPoint protoSwitchPoint;
1965 
1966         if (mh == null) {
1967             mh = Lookup.emptyGetter(returnType);
1968             protoSwitchPoint = getProtoSwitchPoint(name, owner);
1969         } else if (!find.isSelf()) {
1970             assert mh.type().returnType().equals(returnType) : "returntype mismatch for getter " + mh.type().returnType() + " != " + returnType;
1971             if (!property.hasGetterFunction(owner)) {
1972                 // Add a filter that replaces the self object with the prototype owning the property.
1973                 mh = addProtoFilter(mh, find.getProtoChainLength());
1974             }
1975             protoSwitchPoint = getProtoSwitchPoint(name, owner);
1976         } else {
1977             protoSwitchPoint = null;
1978         }
1979 
1980         assert OBJECT_FIELDS_ONLY || guard != null : "we always need a map guard here";
1981 
1982         final GuardedInvocation inv = new GuardedInvocation(mh, guard, protoSwitchPoint, exception);
1983         return inv.addSwitchPoint(reservedNameSwitchPoint);
1984     }
1985 
1986     private static GuardedInvocation findMegaMorphicGetMethod(final CallSiteDescriptor desc, final String name, final boolean isMethod) {
1987         Context.getContextTrusted().getLogger(ObjectClassGenerator.class).warning("Megamorphic getter: " + desc + " " + name + " " +isMethod);
1988         final MethodHandle invoker = MH.insertArguments(MEGAMORPHIC_GET, 1, name, isMethod);
1989         final MethodHandle guard   = getScriptObjectGuard(desc.getMethodType(), true);
1990         return new GuardedInvocation(invoker, guard);
1991     }
1992 
1993     @SuppressWarnings("unused")
1994     private Object megamorphicGet(final String key, final boolean isMethod) {
1995         final FindProperty find = findProperty(key, true);
1996         if (find != null) {
1997             return find.getObjectValue();
1998         }
1999 
2000         return isMethod ? getNoSuchMethod(key, INVALID_PROGRAM_POINT) : invokeNoSuchProperty(key, INVALID_PROGRAM_POINT);
2001     }
2002 
2003     /**
2004      * Find the appropriate GETINDEX method for an invoke dynamic call.
2005      *
2006      * @param desc    the call site descriptor
2007      * @param request the link request
2008      *
2009      * @return GuardedInvocation to be invoked at call site.
2010      */
2011     protected GuardedInvocation findGetIndexMethod(final CallSiteDescriptor desc, final LinkRequest request) {
2012         final MethodType callType                = desc.getMethodType();
2013         final Class<?>   returnType              = callType.returnType();
2014         final Class<?>   returnClass             = returnType.isPrimitive() ? returnType : Object.class;
2015         final Class<?>   keyClass                = callType.parameterType(1);
2016         final boolean    explicitInstanceOfCheck = explicitInstanceOfCheck(desc, request);
2017 
2018         final String name;
2019         if (returnClass.isPrimitive()) {
2020             //turn e.g. get with a double into getDouble
2021             final String returnTypeName = returnClass.getName();
2022             name = "get" + Character.toUpperCase(returnTypeName.charAt(0)) + returnTypeName.substring(1, returnTypeName.length());
2023         } else {
2024             name = "get";
2025         }
2026 
2027         final MethodHandle mh = findGetIndexMethodHandle(returnClass, name, keyClass, desc);
2028         return new GuardedInvocation(mh, getScriptObjectGuard(callType, explicitInstanceOfCheck), (SwitchPoint)null, explicitInstanceOfCheck ? null : ClassCastException.class);
2029     }
2030 
2031     private static MethodHandle getScriptObjectGuard(final MethodType type, final boolean explicitInstanceOfCheck) {
2032         return ScriptObject.class.isAssignableFrom(type.parameterType(0)) ? null : NashornGuards.getScriptObjectGuard(explicitInstanceOfCheck);
2033     }
2034 
2035     /**
2036      * Find a handle for a getIndex method
2037      * @param returnType     return type for getter
2038      * @param name           name
2039      * @param elementType    index type for getter
2040      * @param desc           call site descriptor
2041      * @return method handle for getter
2042      */
2043     protected MethodHandle findGetIndexMethodHandle(final Class<?> returnType, final String name, final Class<?> elementType, final CallSiteDescriptor desc) {
2044         if (!returnType.isPrimitive()) {
2045             return findOwnMH_V(getClass(), name, returnType, elementType);
2046         }
2047 
2048         return MH.insertArguments(
2049                 findOwnMH_V(getClass(), name, returnType, elementType, int.class),
2050                 2,
2051                 NashornCallSiteDescriptor.isOptimistic(desc) ?
2052                         NashornCallSiteDescriptor.getProgramPoint(desc) :
2053                         INVALID_PROGRAM_POINT);
2054     }
2055 
2056     /**
2057      * Get a switch point for a property with the given {@code name} that will be invalidated when
2058      * the property definition is changed in this object's prototype chain. Returns {@code null} if
2059      * the property is defined in this object itself.
2060      *
2061      * @param name the property name
2062      * @param owner the property owner, null if property is not defined
2063      * @return a SwitchPoint or null
2064      */
2065     public final SwitchPoint getProtoSwitchPoint(final String name, final ScriptObject owner) {
2066         if (owner == this || getProto() == null) {
2067             return null;
2068         }
2069 
2070         for (ScriptObject obj = this; obj != owner && obj.getProto() != null; obj = obj.getProto()) {
2071             final ScriptObject parent = obj.getProto();
2072             parent.getMap().addListener(name, obj.getMap());
2073         }
2074 
2075         return getMap().getSwitchPoint(name);
2076     }
2077 
2078     /**
2079      * Find the appropriate SET method for an invoke dynamic call.
2080      *
2081      * @param desc    the call site descriptor
2082      * @param request the link request
2083      *
2084      * @return GuardedInvocation to be invoked at call site.
2085      */
2086     protected GuardedInvocation findSetMethod(final CallSiteDescriptor desc, final LinkRequest request) {
2087         final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
2088 
2089         if (request.isCallSiteUnstable() || hasWithScope()) {
2090             return findMegaMorphicSetMethod(desc, name);
2091         }
2092 
2093         final boolean scope                   = isScope();
2094         final boolean explicitInstanceOfCheck = explicitInstanceOfCheck(desc, request);
2095 
2096         /*
2097          * If doing property set on a scope object, we should stop proto search on the first
2098          * non-scope object. Without this, for example, when assigning "toString" on global scope,
2099          * we'll end up assigning it on it's proto - which is Object.prototype.toString !!
2100          *
2101          * toString = function() { print("global toString"); } // don't affect Object.prototype.toString
2102          */
2103         FindProperty find = findProperty(name, true, scope, this);
2104 
2105         // If it's not a scope search, then we don't want any inherited properties except those with user defined accessors.
2106         if (!scope && find != null && find.isInherited() && !(find.getProperty() instanceof UserAccessorProperty)) {
2107             // We should still check if inherited data property is not writable
2108             if (isExtensible() && !find.getProperty().isWritable()) {
2109                 return createEmptySetMethod(desc, explicitInstanceOfCheck, "property.not.writable", false);
2110             }
2111             // Otherwise, forget the found property
2112             find = null;
2113         }
2114 
2115         if (find != null) {
2116             if (!find.getProperty().isWritable()) {
2117                 // Existing, non-writable property
2118                 return createEmptySetMethod(desc, explicitInstanceOfCheck, "property.not.writable", true);
2119             }
2120         } else {
2121             if (!isExtensible()) {
2122                 return createEmptySetMethod(desc, explicitInstanceOfCheck, "object.non.extensible", false);
2123             }
2124         }
2125 
2126         final GuardedInvocation inv = new SetMethodCreator(this, find, desc, explicitInstanceOfCheck).createGuardedInvocation();
2127 
2128         final GuardedInvocation cinv = Global.getConstants().findSetMethod(find, this, inv, desc, request);
2129         if (cinv != null) {
2130             return cinv;
2131         }
2132 
2133         return inv;
2134     }
2135 
2136     private GuardedInvocation createEmptySetMethod(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String strictErrorMessage, final boolean canBeFastScope) {
2137         final String  name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
2138          if (NashornCallSiteDescriptor.isStrict(desc)) {
2139            throw typeError(strictErrorMessage, name, ScriptRuntime.safeToString(this));
2140         }
2141         assert canBeFastScope || !NashornCallSiteDescriptor.isFastScope(desc);
2142         return new GuardedInvocation(
2143                 Lookup.EMPTY_SETTER,
2144                 NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck),
2145                 getProtoSwitchPoint(name, null),
2146                 explicitInstanceOfCheck ? null : ClassCastException.class);
2147     }
2148 
2149     @SuppressWarnings("unused")
2150     private boolean extensionCheck(final boolean isStrict, final String name) {
2151         if (isExtensible()) {
2152             return true; //go on and do the set. this is our guard
2153         } else if (isStrict) {
2154             //throw an error for attempting to do the set in strict mode
2155             throw typeError("object.non.extensible", name, ScriptRuntime.safeToString(this));
2156         } else {
2157             //not extensible, non strict - this is a nop
2158             return false;
2159         }
2160     }
2161 
2162     private GuardedInvocation findMegaMorphicSetMethod(final CallSiteDescriptor desc, final String name) {
2163         final MethodType        type = desc.getMethodType().insertParameterTypes(1, Object.class);
2164         //never bother with ClassCastExceptionGuard for megamorphic callsites
2165         final GuardedInvocation inv = findSetIndexMethod(getClass(), false, type, NashornCallSiteDescriptor.isStrict(desc));
2166         return inv.replaceMethods(MH.insertArguments(inv.getInvocation(), 1, name), inv.getGuard());
2167     }
2168 
2169     @SuppressWarnings("unused")
2170     private static Object globalFilter(final Object object) {
2171         ScriptObject sobj = (ScriptObject) object;
2172         while (sobj != null && !(sobj instanceof Global)) {
2173             sobj = sobj.getProto();
2174         }
2175         return sobj;
2176     }
2177 
2178     /**
2179      * Lookup function for the set index method, available for subclasses as well, e.g. {@link NativeArray}
2180      * provides special quick accessor linkage for continuous arrays that are represented as Java arrays
2181      *
2182      * @param desc    call site descriptor
2183      * @param request link request
2184      *
2185      * @return GuardedInvocation to be invoked at call site.
2186      */
2187     protected GuardedInvocation findSetIndexMethod(final CallSiteDescriptor desc, final LinkRequest request) { // array, index, value
2188         return findSetIndexMethod(getClass(), explicitInstanceOfCheck(desc, request), desc.getMethodType(), NashornCallSiteDescriptor.isStrict(desc));
2189     }
2190 
2191     /**
2192      * Find the appropriate SETINDEX method for an invoke dynamic call.
2193      *
2194      * @param callType the method type at the call site
2195      * @param isStrict are we in strict mode?
2196      *
2197      * @return GuardedInvocation to be invoked at call site.
2198      */
2199     private static GuardedInvocation findSetIndexMethod(final Class<? extends ScriptObject> clazz, final boolean explicitInstanceOfCheck, final MethodType callType, final boolean isStrict) {
2200         assert callType.parameterCount() == 3;
2201         final Class<?> keyClass   = callType.parameterType(1);
2202         final Class<?> valueClass = callType.parameterType(2);
2203 
2204         MethodHandle methodHandle = findOwnMH_V(clazz, "set", void.class, keyClass, valueClass, boolean.class);
2205         methodHandle = MH.insertArguments(methodHandle, 3, isStrict);
2206 
2207         return new GuardedInvocation(methodHandle, getScriptObjectGuard(callType, explicitInstanceOfCheck), (SwitchPoint)null, explicitInstanceOfCheck ? null : ClassCastException.class);
2208     }
2209 
2210     /**
2211      * Fall back if a function property is not found.
2212      * @param desc The call site descriptor
2213      * @param request the link request
2214      * @return GuardedInvocation to be invoked at call site.
2215      */
2216     public GuardedInvocation noSuchMethod(final CallSiteDescriptor desc, final LinkRequest request) {
2217         final String       name      = desc.getNameToken(2);
2218         final FindProperty find      = findProperty(NO_SUCH_METHOD_NAME, true);
2219         final boolean      scopeCall = isScope() && NashornCallSiteDescriptor.isScope(desc);
2220 
2221         if (find == null) {
2222             return noSuchProperty(desc, request);
2223         }
2224 
2225         final boolean explicitInstanceOfCheck = explicitInstanceOfCheck(desc, request);
2226 
2227         final Object value = find.getObjectValue();
2228         if (!(value instanceof ScriptFunction)) {
2229             return createEmptyGetter(desc, explicitInstanceOfCheck, name);
2230         }
2231 
2232         final ScriptFunction func = (ScriptFunction)value;
2233         final Object         thiz = scopeCall && func.isStrict() ? ScriptRuntime.UNDEFINED : this;
2234         // TODO: It'd be awesome if we could bind "name" without binding "this".
2235         return new GuardedInvocation(
2236                 MH.dropArguments(
2237                         MH.constant(
2238                                 ScriptFunction.class,
2239                                 func.makeBoundFunction(thiz, new Object[] { name })),
2240                         0,
2241                         Object.class),
2242                 NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck),
2243                 (SwitchPoint)null,
2244                 explicitInstanceOfCheck ? null : ClassCastException.class);
2245     }
2246 
2247     /**
2248      * Fall back if a property is not found.
2249      * @param desc the call site descriptor.
2250      * @param request the link request
2251      * @return GuardedInvocation to be invoked at call site.
2252      */
2253     public GuardedInvocation noSuchProperty(final CallSiteDescriptor desc, final LinkRequest request) {
2254         final String       name        = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
2255         final FindProperty find        = findProperty(NO_SUCH_PROPERTY_NAME, true);
2256         final boolean      scopeAccess = isScope() && NashornCallSiteDescriptor.isScope(desc);
2257 
2258         if (find != null) {
2259             final Object   value = find.getObjectValue();
2260             ScriptFunction func  = null;
2261             MethodHandle   mh    = null;
2262 
2263             if (value instanceof ScriptFunction) {
2264                 func = (ScriptFunction)value;
2265                 mh   = getCallMethodHandle(func, desc.getMethodType(), name);
2266             }
2267 
2268             if (mh != null) {
2269                 assert func != null;
2270                 if (scopeAccess && func != null && func.isStrict()) {
2271                     mh = bindTo(mh, UNDEFINED);
2272                 }
2273                 return new GuardedInvocation(
2274                         mh,
2275                         //TODO this always does a scriptobject check
2276                         getKnownFunctionPropertyGuard(
2277                                 getMap(),
2278                                 find.getGetter(Object.class, INVALID_PROGRAM_POINT),
2279                                 find.getOwner(),
2280                                 func),
2281                         getProtoSwitchPoint(NO_SUCH_PROPERTY_NAME, find.getOwner()),
2282                         //TODO this doesn't need a ClassCastException as guard always checks script object
2283                         null);
2284             }
2285         }
2286 
2287         if (scopeAccess) {
2288             throw referenceError("not.defined", name);
2289         }
2290 
2291         return createEmptyGetter(desc, explicitInstanceOfCheck(desc, request), name);
2292     }
2293 
2294     /**
2295      * Invoke fall back if a property is not found.
2296      * @param name Name of property.
2297      * @param programPoint program point
2298      * @return Result from call.
2299      */
2300     protected Object invokeNoSuchProperty(final String name, final int programPoint) {
2301         final FindProperty find = findProperty(NO_SUCH_PROPERTY_NAME, true);
2302 
2303         Object ret = UNDEFINED;
2304 
2305         if (find != null) {
2306             final Object func = find.getObjectValue();
2307 
2308             if (func instanceof ScriptFunction) {
2309                 ret = ScriptRuntime.apply((ScriptFunction)func, this, name);
2310             }
2311         }
2312 
2313         if (isValid(programPoint)) {
2314             throw new UnwarrantedOptimismException(ret, programPoint);
2315         }
2316 
2317         return ret;
2318     }
2319 
2320 
2321     /**
2322      * Get __noSuchMethod__ as a function bound to this object and {@code name} if it is defined.
2323      * @param name the method name
2324      * @return the bound function, or undefined
2325      */
2326     private Object getNoSuchMethod(final String name, final int programPoint) {
2327         final FindProperty find = findProperty(NO_SUCH_METHOD_NAME, true);
2328 
2329         if (find == null) {
2330             return invokeNoSuchProperty(name, programPoint);
2331         }
2332 
2333         final Object value = find.getObjectValue();
2334         if (!(value instanceof ScriptFunction)) {
2335             return UNDEFINED;
2336         }
2337 
2338         return ((ScriptFunction)value).makeBoundFunction(this, new Object[] {name});
2339     }
2340 
2341     private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
2342         if (NashornCallSiteDescriptor.isOptimistic(desc)) {
2343             throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
2344         }
2345 
2346         return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
2347                 NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoint(name, null),
2348                 explicitInstanceOfCheck ? null : ClassCastException.class);
2349     }
2350 
2351     private abstract static class ScriptObjectIterator <T extends Object> implements Iterator<T> {
2352         protected T[] values;
2353         protected final ScriptObject object;
2354         private int index;
2355 
2356         ScriptObjectIterator(final ScriptObject object) {
2357             this.object = object;
2358         }
2359 
2360         protected abstract void init();
2361 
2362         @Override
2363         public boolean hasNext() {
2364             if (values == null) {
2365                 init();
2366             }
2367             return index < values.length;
2368         }
2369 
2370         @Override
2371         public T next() {
2372             if (values == null) {
2373                 init();
2374             }
2375             return values[index++];
2376         }
2377 
2378         @Override
2379         public void remove() {
2380             throw new UnsupportedOperationException();
2381         }
2382     }
2383 
2384     private static class KeyIterator extends ScriptObjectIterator<String> {
2385         KeyIterator(final ScriptObject object) {
2386             super(object);
2387         }
2388 
2389         @Override
2390         protected void init() {
2391             final Set<String> keys = new LinkedHashSet<>();
2392             for (ScriptObject self = object; self != null; self = self.getProto()) {
2393                 keys.addAll(Arrays.asList(self.getOwnKeys(false)));
2394             }
2395             this.values = keys.toArray(new String[keys.size()]);
2396         }
2397     }
2398 
2399     private static class ValueIterator extends ScriptObjectIterator<Object> {
2400         ValueIterator(final ScriptObject object) {
2401             super(object);
2402         }
2403 
2404         @Override
2405         protected void init() {
2406             final ArrayList<Object> valueList = new ArrayList<>();
2407             for (ScriptObject self = object; self != null; self = self.getProto()) {
2408                 for (final String key : self.getOwnKeys(false)) {
2409                     valueList.add(self.get(key));
2410                 }
2411             }
2412             this.values = valueList.toArray(new Object[valueList.size()]);
2413         }
2414     }
2415 
2416     /**
2417      * Add a spill property for the given key.
2418      * @param key           Property key.
2419      * @param propertyFlags Property flags.
2420      * @return Added property.
2421      */
2422     private Property addSpillProperty(final String key, final int propertyFlags, final Object value, final boolean hasInitialValue) {
2423         final PropertyMap propertyMap = getMap();
2424         final int         fieldCount  = propertyMap.getFieldCount();
2425         final int         fieldMax    = propertyMap.getFieldMaximum();
2426 
2427         Property property;
2428         if (fieldCount < fieldMax) {
2429             property = hasInitialValue ?
2430                 new AccessorProperty(key, propertyFlags, fieldCount, this, value) :
2431                 new AccessorProperty(key, propertyFlags, getClass(), fieldCount);
2432             property = addOwnProperty(property);
2433         } else {
2434             final int spillCount = propertyMap.getSpillLength();
2435             property = hasInitialValue ?
2436                 new SpillProperty(key, propertyFlags, spillCount, this, value) :
2437                 new SpillProperty(key, propertyFlags, spillCount);
2438             property = addOwnProperty(property);
2439             ensureSpillSize(property.getSlot());
2440         }
2441         return property;
2442     }
2443 
2444     /**
2445      * Add a spill entry for the given key.
2446      * @param key Property key.
2447      * @return Setter method handle.
2448      */
2449     MethodHandle addSpill(final Class<?> type, final String key) {
2450         return addSpillProperty(key, 0, null, false).getSetter(OBJECT_FIELDS_ONLY ? Object.class : type, getMap());
2451     }
2452 
2453     /**
2454      * Make sure arguments are paired correctly, with respect to more parameters than declared,
2455      * fewer parameters than declared and other things that JavaScript allows. This might involve
2456      * creating collectors.
2457      *
2458      * @param methodHandle method handle for invoke
2459      * @param callType     type of the call
2460      *
2461      * @return method handle with adjusted arguments
2462      */
2463     protected static MethodHandle pairArguments(final MethodHandle methodHandle, final MethodType callType) {
2464         return pairArguments(methodHandle, callType, null);
2465     }
2466 
2467     /**
2468      * Make sure arguments are paired correctly, with respect to more parameters than declared,
2469      * fewer parameters than declared and other things that JavaScript allows. This might involve
2470      * creating collectors.
2471      *
2472      * Make sure arguments are paired correctly.
2473      * @param methodHandle MethodHandle to adjust.
2474      * @param callType     MethodType of the call site.
2475      * @param callerVarArg true if the caller is vararg, false otherwise, null if it should be inferred from the
2476      * {@code callType}; basically, if the last parameter type of the call site is an array, it'll be considered a
2477      * variable arity call site. These are ordinarily rare; Nashorn code generator creates variable arity call sites
2478      * when the call has more than {@link LinkerCallSite#ARGLIMIT} parameters.
2479      *
2480      * @return method handle with adjusted arguments
2481      */
2482     public static MethodHandle pairArguments(final MethodHandle methodHandle, final MethodType callType, final Boolean callerVarArg) {
2483         final MethodType methodType = methodHandle.type();
2484         if (methodType.equals(callType.changeReturnType(methodType.returnType()))) {
2485             return methodHandle;
2486         }
2487 
2488         final int parameterCount = methodType.parameterCount();
2489         final int callCount      = callType.parameterCount();
2490 
2491         final boolean isCalleeVarArg = parameterCount > 0 && methodType.parameterType(parameterCount - 1).isArray();
2492         final boolean isCallerVarArg = callerVarArg != null ? callerVarArg.booleanValue() : callCount > 0 &&
2493                 callType.parameterType(callCount - 1).isArray();
2494 
2495         if (isCalleeVarArg) {
2496             return isCallerVarArg ?
2497                 methodHandle :
2498                 MH.asCollector(methodHandle, Object[].class, callCount - parameterCount + 1);
2499         }
2500 
2501         if (isCallerVarArg) {
2502             final int spreadArgs = parameterCount - callCount + 1;
2503             return MH.filterArguments(
2504                 MH.asSpreader(
2505                     methodHandle,
2506                     Object[].class,
2507                     spreadArgs),
2508                 callCount - 1,
2509                 MH.insertArguments(
2510                     TRUNCATINGFILTER,
2511                     0,
2512                     spreadArgs)
2513                 );
2514         }
2515 
2516         if (callCount < parameterCount) {
2517             final int      missingArgs = parameterCount - callCount;
2518             final Object[] fillers     = new Object[missingArgs];
2519 
2520             Arrays.fill(fillers, UNDEFINED);
2521 
2522             if (isCalleeVarArg) {
2523                 fillers[missingArgs - 1] = ScriptRuntime.EMPTY_ARRAY;
2524             }
2525 
2526             return MH.insertArguments(
2527                 methodHandle,
2528                 parameterCount - missingArgs,
2529                 fillers);
2530         }
2531 
2532         if (callCount > parameterCount) {
2533             final int discardedArgs = callCount - parameterCount;
2534 
2535             final Class<?>[] discards = new Class<?>[discardedArgs];
2536             Arrays.fill(discards, Object.class);
2537 
2538             return MH.dropArguments(methodHandle, callCount - discardedArgs, discards);
2539         }
2540 
2541         return methodHandle;
2542     }
2543 
2544     @SuppressWarnings("unused")
2545     private static Object[] truncatingFilter(final int n, final Object[] array) {
2546         final int length = array == null ? 0 : array.length;
2547         if (n == length) {
2548             return array == null ? ScriptRuntime.EMPTY_ARRAY : array;
2549         }
2550 
2551         final Object[] newArray = new Object[n];
2552 
2553         if (array != null) {
2554             System.arraycopy(array, 0, newArray, 0, Math.min(n, length));
2555         }
2556 
2557         if (length < n) {
2558             final Object fill = UNDEFINED;
2559 
2560             for (int i = length; i < n; i++) {
2561                 newArray[i] = fill;
2562             }
2563         }
2564 
2565         return newArray;
2566     }
2567 
2568     /**
2569       * Numeric length setter for length property
2570       *
2571       * @param newLength new length to set
2572       */
2573     public final void setLength(final long newLength) {
2574        final long arrayLength = getArray().length();
2575        if (newLength == arrayLength) {
2576            return;
2577        }
2578 
2579        if (newLength > arrayLength) {
2580            setArray(getArray().ensure(newLength - 1));
2581             if (getArray().canDelete(arrayLength, newLength - 1, false)) {
2582                setArray(getArray().delete(arrayLength, newLength - 1));
2583            }
2584            return;
2585        }
2586 
2587        if (newLength < arrayLength) {
2588            long actualLength = newLength;
2589 
2590            // Check for numeric keys in property map and delete them or adjust length, depending on whether
2591            // they're defined as configurable. See ES5 #15.4.5.2
2592            if (getMap().containsArrayKeys()) {
2593 
2594                for (long l = arrayLength - 1; l >= newLength; l--) {
2595                    final FindProperty find = findProperty(JSType.toString(l), false);
2596 
2597                    if (find != null) {
2598 
2599                        if (find.getProperty().isConfigurable()) {
2600                            deleteOwnProperty(find.getProperty());
2601                        } else {
2602                            actualLength = l + 1;
2603                            break;
2604                        }
2605                    }
2606                }
2607            }
2608 
2609            setArray(getArray().shrink(actualLength));
2610            getArray().setLength(actualLength);
2611        }
2612     }
2613 
2614     private int getInt(final int index, final String key, final int programPoint) {
2615         if (isValidArrayIndex(index)) {
2616             for (ScriptObject object = this; ; ) {
2617                 if (object.getMap().containsArrayKeys()) {
2618                     final FindProperty find = object.findProperty(key, false, false, this);
2619 
2620                     if (find != null) {
2621                         return getIntValue(find, programPoint);
2622                     }
2623                 }
2624 
2625                 if ((object = object.getProto()) == null) {
2626                     break;
2627                 }
2628 
2629                 final ArrayData array = object.getArray();
2630 
2631                 if (array.has(index)) {
2632                     return isValid(programPoint) ?
2633                         array.getIntOptimistic(index, programPoint) :
2634                         array.getInt(index);
2635                 }
2636             }
2637         } else {
2638             final FindProperty find = findProperty(key, true);
2639 
2640             if (find != null) {
2641                 return getIntValue(find, programPoint);
2642             }
2643         }
2644 
2645         return JSType.toInt32(invokeNoSuchProperty(key, programPoint));
2646     }
2647 
2648     @Override
2649     public int getInt(final Object key, final int programPoint) {
2650         final Object    primitiveKey = JSType.toPrimitive(key, String.class);
2651         final int       index        = getArrayIndex(primitiveKey);
2652         final ArrayData array        = getArray();
2653 
2654         if (array.has(index)) {
2655             return isValid(programPoint) ? array.getIntOptimistic(index, programPoint) : array.getInt(index);
2656         }
2657 
2658         return getInt(index, JSType.toString(primitiveKey), programPoint);
2659     }
2660 
2661     @Override
2662     public int getInt(final double key, final int programPoint) {
2663         final int       index = getArrayIndex(key);
2664         final ArrayData array = getArray();
2665 
2666         if (array.has(index)) {
2667             return isValid(programPoint) ? array.getIntOptimistic(index, programPoint) : array.getInt(index);
2668         }
2669 
2670         return getInt(index, JSType.toString(key), programPoint);
2671     }
2672 
2673     @Override
2674     public int getInt(final long key, final int programPoint) {
2675         final int       index = getArrayIndex(key);
2676         final ArrayData array = getArray();
2677 
2678         if (array.has(index)) {
2679             return isValid(programPoint) ? array.getIntOptimistic(index, programPoint) : array.getInt(index);
2680         }
2681 
2682         return getInt(index, JSType.toString(key), programPoint);
2683     }
2684 
2685     @Override
2686     public int getInt(final int key, final int programPoint) {
2687         final int       index = getArrayIndex(key);
2688         final ArrayData array = getArray();
2689 
2690         if (array.has(index)) {
2691             return isValid(programPoint) ? array.getIntOptimistic(key, programPoint) : array.getInt(key);
2692         }
2693 
2694         return getInt(index, JSType.toString(key), programPoint);
2695     }
2696 
2697     private long getLong(final int index, final String key, final int programPoint) {
2698         if (isValidArrayIndex(index)) {
2699             for (ScriptObject object = this; ; ) {
2700                 if (object.getMap().containsArrayKeys()) {
2701                     final FindProperty find = object.findProperty(key, false, false, this);
2702                     if (find != null) {
2703                         return getLongValue(find, programPoint);
2704                     }
2705                 }
2706 
2707                 if ((object = object.getProto()) == null) {
2708                     break;
2709                 }
2710 
2711                 final ArrayData array = object.getArray();
2712 
2713                 if (array.has(index)) {
2714                     return isValid(programPoint) ?
2715                         array.getLongOptimistic(index, programPoint) :
2716                         array.getLong(index);
2717                 }
2718             }
2719         } else {
2720             final FindProperty find = findProperty(key, true);
2721 
2722             if (find != null) {
2723                 return getLongValue(find, programPoint);
2724             }
2725         }
2726 
2727         return JSType.toLong(invokeNoSuchProperty(key, programPoint));
2728     }
2729 
2730     @Override
2731     public long getLong(final Object key, final int programPoint) {
2732         final Object    primitiveKey = JSType.toPrimitive(key, String.class);
2733         final int       index        = getArrayIndex(primitiveKey);
2734         final ArrayData array        = getArray();
2735 
2736         if (array.has(index)) {
2737             return isValid(programPoint) ? array.getLongOptimistic(index, programPoint) : array.getLong(index);
2738         }
2739 
2740         return getLong(index, JSType.toString(primitiveKey), programPoint);
2741     }
2742 
2743     @Override
2744     public long getLong(final double key, final int programPoint) {
2745         final int       index = getArrayIndex(key);
2746         final ArrayData array = getArray();
2747 
2748         if (array.has(index)) {
2749             return isValid(programPoint) ? array.getLongOptimistic(index, programPoint) : array.getLong(index);
2750         }
2751 
2752         return getLong(index, JSType.toString(key), programPoint);
2753     }
2754 
2755     @Override
2756     public long getLong(final long key, final int programPoint) {
2757         final int       index = getArrayIndex(key);
2758         final ArrayData array = getArray();
2759 
2760         if (array.has(index)) {
2761             return isValid(programPoint) ? array.getLongOptimistic(index, programPoint) : array.getLong(index);
2762         }
2763 
2764         return getLong(index, JSType.toString(key), programPoint);
2765     }
2766 
2767     @Override
2768     public long getLong(final int key, final int programPoint) {
2769         final int       index = getArrayIndex(key);
2770         final ArrayData array = getArray();
2771 
2772         if (array.has(index)) {
2773             return isValid(programPoint) ? array.getLongOptimistic(key, programPoint) : array.getLong(key);
2774         }
2775 
2776         return getLong(index, JSType.toString(key), programPoint);
2777     }
2778 
2779     private double getDouble(final int index, final String key, final int programPoint) {
2780         if (isValidArrayIndex(index)) {
2781             for (ScriptObject object = this; ; ) {
2782                 if (object.getMap().containsArrayKeys()) {
2783                     final FindProperty find = object.findProperty(key, false, false, this);
2784                     if (find != null) {
2785                         return getDoubleValue(find, programPoint);
2786                     }
2787                 }
2788 
2789                 if ((object = object.getProto()) == null) {
2790                     break;
2791                 }
2792 
2793                 final ArrayData array = object.getArray();
2794 
2795                 if (array.has(index)) {
2796                     return isValid(programPoint) ?
2797                         array.getDoubleOptimistic(index, programPoint) :
2798                         array.getDouble(index);
2799                 }
2800             }
2801         } else {
2802             final FindProperty find = findProperty(key, true);
2803 
2804             if (find != null) {
2805                 return getDoubleValue(find, programPoint);
2806             }
2807         }
2808 
2809         return JSType.toNumber(invokeNoSuchProperty(key, INVALID_PROGRAM_POINT));
2810     }
2811 
2812     @Override
2813     public double getDouble(final Object key, final int programPoint) {
2814         final Object    primitiveKey = JSType.toPrimitive(key, String.class);
2815         final int       index        = getArrayIndex(primitiveKey);
2816         final ArrayData array        = getArray();
2817 
2818         if (array.has(index)) {
2819             return isValid(programPoint) ? array.getDoubleOptimistic(index, programPoint) : array.getDouble(index);
2820         }
2821 
2822         return getDouble(index, JSType.toString(primitiveKey), programPoint);
2823     }
2824 
2825     @Override
2826     public double getDouble(final double key, final int programPoint) {
2827         final int       index = getArrayIndex(key);
2828         final ArrayData array = getArray();
2829 
2830         if (array.has(index)) {
2831             return isValid(programPoint) ? array.getDoubleOptimistic(index, programPoint) : array.getDouble(index);
2832         }
2833 
2834         return getDouble(index, JSType.toString(key), programPoint);
2835     }
2836 
2837     @Override
2838     public double getDouble(final long key, final int programPoint) {
2839         final int       index = getArrayIndex(key);
2840         final ArrayData array = getArray();
2841 
2842         if (array.has(index)) {
2843             return isValid(programPoint) ? array.getDoubleOptimistic(index, programPoint) : array.getDouble(index);
2844         }
2845 
2846         return getDouble(index, JSType.toString(key), programPoint);
2847     }
2848 
2849     @Override
2850     public double getDouble(final int key, final int programPoint) {
2851         final int       index = getArrayIndex(key);
2852         final ArrayData array = getArray();
2853 
2854         if (array.has(index)) {
2855             return isValid(programPoint) ? array.getDoubleOptimistic(key, programPoint) : array.getDouble(key);
2856         }
2857 
2858         return getDouble(index, JSType.toString(key), programPoint);
2859     }
2860 
2861     private Object get(final int index, final String key) {
2862         if (isValidArrayIndex(index)) {
2863             for (ScriptObject object = this; ; ) {
2864                 if (object.getMap().containsArrayKeys()) {
2865                     final FindProperty find = object.findProperty(key, false, false, this);
2866 
2867                     if (find != null) {
2868                         return find.getObjectValue();
2869                     }
2870                 }
2871 
2872                 if ((object = object.getProto()) == null) {
2873                     break;
2874                 }
2875 
2876                 final ArrayData array = object.getArray();
2877 
2878                 if (array.has(index)) {
2879                     return array.getObject(index);
2880                 }
2881             }
2882         } else {
2883             final FindProperty find = findProperty(key, true);
2884 
2885             if (find != null) {
2886                 return find.getObjectValue();
2887             }
2888         }
2889 
2890         return invokeNoSuchProperty(key, INVALID_PROGRAM_POINT);
2891     }
2892 
2893     @Override
2894     public Object get(final Object key) {
2895         final Object    primitiveKey = JSType.toPrimitive(key, String.class);
2896         final int       index        = getArrayIndex(primitiveKey);
2897         final ArrayData array        = getArray();
2898 
2899         if (array.has(index)) {
2900             return array.getObject(index);
2901         }
2902 
2903         return get(index, JSType.toString(primitiveKey));
2904     }
2905 
2906     @Override
2907     public Object get(final double key) {
2908         final int index = getArrayIndex(key);
2909         final ArrayData array = getArray();
2910 
2911         if (array.has(index)) {
2912             return array.getObject(index);
2913         }
2914 
2915         return get(index, JSType.toString(key));
2916     }
2917 
2918     @Override
2919     public Object get(final long key) {
2920         final int index = getArrayIndex(key);
2921         final ArrayData array = getArray();
2922 
2923         if (array.has(index)) {
2924             return array.getObject(index);
2925         }
2926 
2927         return get(index, JSType.toString(key));
2928     }
2929 
2930     @Override
2931     public Object get(final int key) {
2932         final int index = getArrayIndex(key);
2933         final ArrayData array = getArray();
2934 
2935         if (array.has(index)) {
2936             return array.getObject(index);
2937         }
2938 
2939         return get(index, JSType.toString(key));
2940     }
2941 
2942     private boolean doesNotHaveCheckArrayKeys(final long longIndex, final int value, final boolean strict) {
2943         if (getMap().containsArrayKeys()) {
2944             final String       key  = JSType.toString(longIndex);
2945             final FindProperty find = findProperty(key, true);
2946             if (find != null) {
2947                 setObject(find, strict, key, value);
2948                 return true;
2949             }
2950         }
2951         return false;
2952     }
2953 
2954     private boolean doesNotHaveCheckArrayKeys(final long longIndex, final long value, final boolean strict) {
2955         if (getMap().containsArrayKeys()) {
2956             final String       key  = JSType.toString(longIndex);
2957             final FindProperty find = findProperty(key, true);
2958             if (find != null) {
2959                 setObject(find, strict, key, value);
2960                 return true;
2961             }
2962         }
2963         return false;
2964     }
2965 
2966     private boolean doesNotHaveCheckArrayKeys(final long longIndex, final double value, final boolean strict) {
2967          if (getMap().containsArrayKeys()) {
2968             final String       key  = JSType.toString(longIndex);
2969             final FindProperty find = findProperty(key, true);
2970             if (find != null) {
2971                 setObject(find, strict, key, value);
2972                 return true;
2973             }
2974         }
2975         return false;
2976     }
2977 
2978     private boolean doesNotHaveCheckArrayKeys(final long longIndex, final Object value, final boolean strict) {
2979         if (getMap().containsArrayKeys()) {
2980             final String       key  = JSType.toString(longIndex);
2981             final FindProperty find = findProperty(key, true);
2982             if (find != null) {
2983                 setObject(find, strict, key, value);
2984                 return true;
2985             }
2986         }
2987         return false;
2988     }
2989 
2990     //value agnostic
2991     private boolean doesNotHaveEnsureLength(final long longIndex, final long oldLength, final boolean strict) {
2992         if (longIndex >= oldLength) {
2993             if (!isExtensible()) {
2994                 if (strict) {
2995                     throw typeError("object.non.extensible", JSType.toString(longIndex), ScriptRuntime.safeToString(this));
2996                 }
2997                 return true;
2998             }
2999             setArray(getArray().ensure(longIndex));
3000         }
3001         return false;
3002     }
3003 
3004     private void doesNotHaveEnsureDelete(final long longIndex, final long oldLength, final boolean strict) {
3005         if (longIndex > oldLength) {
3006             ArrayData array = getArray();
3007             if (array.canDelete(oldLength, longIndex - 1, strict)) {
3008                 array = array.delete(oldLength, longIndex - 1);
3009             }
3010             setArray(array);
3011         }
3012     }
3013 
3014     private void doesNotHave(final int index, final int value, final boolean strict) {
3015         final long oldLength = getArray().length();
3016         final long longIndex = ArrayIndex.toLongIndex(index);
3017         if (!doesNotHaveCheckArrayKeys(longIndex, value, strict) && !doesNotHaveEnsureLength(longIndex, oldLength, strict)) {
3018             setArray(getArray().set(index, value, strict));
3019             doesNotHaveEnsureDelete(longIndex, oldLength, strict);
3020         }
3021     }
3022 
3023     private void doesNotHave(final int index, final long value, final boolean strict) {
3024         final long oldLength = getArray().length();
3025         final long longIndex = ArrayIndex.toLongIndex(index);
3026         if (!doesNotHaveCheckArrayKeys(longIndex, value, strict) && !doesNotHaveEnsureLength(longIndex, oldLength, strict)) {
3027             setArray(getArray().set(index, value, strict));
3028             doesNotHaveEnsureDelete(longIndex, oldLength, strict);
3029         }
3030     }
3031 
3032     private void doesNotHave(final int index, final double value, final boolean strict) {
3033         final long oldLength = getArray().length();
3034         final long longIndex = ArrayIndex.toLongIndex(index);
3035         if (!doesNotHaveCheckArrayKeys(longIndex, value, strict) && !doesNotHaveEnsureLength(longIndex, oldLength, strict)) {
3036             setArray(getArray().set(index, value, strict));
3037             doesNotHaveEnsureDelete(longIndex, oldLength, strict);
3038         }
3039     }
3040 
3041     private void doesNotHave(final int index, final Object value, final boolean strict) {
3042         final long oldLength = getArray().length();
3043         final long longIndex = ArrayIndex.toLongIndex(index);
3044         if (!doesNotHaveCheckArrayKeys(longIndex, value, strict) && !doesNotHaveEnsureLength(longIndex, oldLength, strict)) {
3045             setArray(getArray().set(index, value, strict));
3046             doesNotHaveEnsureDelete(longIndex, oldLength, strict);
3047         }
3048     }
3049 
3050     /**
3051      * This is the most generic of all Object setters. Most of the others use this in some form.
3052      * TODO: should be further specialized
3053      *
3054      * @param find    found property
3055      * @param strict  are we in strict mode
3056      * @param key     property key
3057      * @param value   property value
3058      */
3059     public final void setObject(final FindProperty find, final boolean strict, final String key, final Object value) {
3060         FindProperty f = find;
3061 
3062         if (f != null && f.isInherited() && !(f.getProperty() instanceof UserAccessorProperty) && !isScope()) {
3063             // Setting a property should not modify the property in prototype unless this is a scope object.
3064             f = null;
3065         }
3066 
3067         if (f != null) {
3068             if (!f.getProperty().isWritable()) {
3069                 if (strict) {
3070                     throw typeError("property.not.writable", key, ScriptRuntime.safeToString(this));
3071                 }
3072 
3073                 return;
3074             }
3075 
3076             f.setValue(value, strict);
3077 
3078         } else if (!isExtensible()) {
3079             if (strict) {
3080                 throw typeError("object.non.extensible", key, ScriptRuntime.safeToString(this));
3081             }
3082         } else {
3083             ScriptObject sobj = this;
3084             // undefined scope properties are set in the global object.
3085             if (isScope()) {
3086                 while (sobj != null && !(sobj instanceof Global)) {
3087                     sobj = sobj.getProto();
3088                 }
3089                 assert sobj != null : "no parent global object in scope";
3090             }
3091             //this will unbox any Number object to its primitive type in case the
3092             //property supports primitive types, so it doesn't matter that it comes
3093             //in as an Object.
3094             sobj.addSpillProperty(key, 0, value, true);
3095         }
3096     }
3097 
3098     @Override
3099     public void set(final Object key, final int value, final boolean strict) {
3100         final Object primitiveKey = JSType.toPrimitive(key, String.class);
3101         final int    index        = getArrayIndex(primitiveKey);
3102 
3103         if (isValidArrayIndex(index)) {
3104             if (getArray().has(index)) {
3105                 setArray(getArray().set(index, value, strict));
3106             } else {
3107                 doesNotHave(index, value, strict);
3108             }
3109 
3110             return;
3111         }
3112 
3113         final String propName = JSType.toString(primitiveKey);
3114         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3115     }
3116 
3117     @Override
3118     public void set(final Object key, final long value, final boolean strict) {
3119         final Object primitiveKey = JSType.toPrimitive(key, String.class);
3120         final int    index        = getArrayIndex(primitiveKey);
3121 
3122         if (isValidArrayIndex(index)) {
3123             if (getArray().has(index)) {
3124                 setArray(getArray().set(index, value, strict));
3125             } else {
3126                 doesNotHave(index, value, strict);
3127             }
3128 
3129             return;
3130         }
3131 
3132         final String propName = JSType.toString(primitiveKey);
3133         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3134     }
3135 
3136     @Override
3137     public void set(final Object key, final double value, final boolean strict) {
3138         final Object primitiveKey = JSType.toPrimitive(key, String.class);
3139         final int    index        = getArrayIndex(primitiveKey);
3140 
3141         if (isValidArrayIndex(index)) {
3142             if (getArray().has(index)) {
3143                 setArray(getArray().set(index, value, strict));
3144             } else {
3145                 doesNotHave(index, value, strict);
3146             }
3147 
3148             return;
3149         }
3150 
3151         final String propName = JSType.toString(primitiveKey);
3152         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3153     }
3154 
3155     @Override
3156     public void set(final Object key, final Object value, final boolean strict) {
3157         final Object primitiveKey = JSType.toPrimitive(key, String.class);
3158         final int    index        = getArrayIndex(primitiveKey);
3159 
3160         if (isValidArrayIndex(index)) {
3161             if (getArray().has(index)) {
3162                 setArray(getArray().set(index, value, strict));
3163             } else {
3164                 doesNotHave(index, value, strict);
3165             }
3166 
3167             return;
3168         }
3169 
3170         final String propName = JSType.toString(primitiveKey);
3171         setObject(findProperty(propName, true), strict, propName, value);
3172     }
3173 
3174     @Override
3175     public void set(final double key, final int value, final boolean strict) {
3176         final int index = getArrayIndex(key);
3177 
3178         if (isValidArrayIndex(index)) {
3179             if (getArray().has(index)) {
3180                 setArray(getArray().set(index, value, strict));
3181             } else {
3182                 doesNotHave(index, value, strict);
3183             }
3184 
3185             return;
3186         }
3187 
3188         final String propName = JSType.toString(key);
3189         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3190     }
3191 
3192     @Override
3193     public void set(final double key, final long value, final boolean strict) {
3194         final int index = getArrayIndex(key);
3195 
3196         if (isValidArrayIndex(index)) {
3197             if (getArray().has(index)) {
3198                 setArray(getArray().set(index, value, strict));
3199             } else {
3200                 doesNotHave(index, value, strict);
3201             }
3202 
3203             return;
3204         }
3205 
3206         final String propName = JSType.toString(key);
3207         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3208     }
3209 
3210     @Override
3211     public void set(final double key, final double value, final boolean strict) {
3212         final int index = getArrayIndex(key);
3213 
3214         if (isValidArrayIndex(index)) {
3215             if (getArray().has(index)) {
3216                 setArray(getArray().set(index, value, strict));
3217             } else {
3218                 doesNotHave(index, value, strict);
3219             }
3220 
3221             return;
3222         }
3223 
3224         final String propName = JSType.toString(key);
3225         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3226     }
3227 
3228     @Override
3229     public void set(final double key, final Object value, final boolean strict) {
3230         final int index = getArrayIndex(key);
3231 
3232         if (isValidArrayIndex(index)) {
3233             if (getArray().has(index)) {
3234                 setArray(getArray().set(index, value, strict));
3235             } else {
3236                 doesNotHave(index, value, strict);
3237             }
3238 
3239             return;
3240         }
3241 
3242         final String propName = JSType.toString(key);
3243         setObject(findProperty(propName, true), strict, propName, value);
3244     }
3245 
3246     @Override
3247     public void set(final long key, final int value, final boolean strict) {
3248         final int index = getArrayIndex(key);
3249 
3250         if (isValidArrayIndex(index)) {
3251             if (getArray().has(index)) {
3252                 setArray(getArray().set(index, value, strict));
3253             } else {
3254                 doesNotHave(index, value, strict);
3255             }
3256 
3257             return;
3258         }
3259 
3260         final String propName = JSType.toString(key);
3261         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3262     }
3263 
3264     @Override
3265     public void set(final long key, final long value, final boolean strict) {
3266         final int index = getArrayIndex(key);
3267 
3268         if (isValidArrayIndex(index)) {
3269             if (getArray().has(index)) {
3270                 setArray(getArray().set(index, value, strict));
3271             } else {
3272                 doesNotHave(index, value, strict);
3273             }
3274 
3275             return;
3276         }
3277 
3278         final String propName = JSType.toString(key);
3279         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3280     }
3281 
3282     @Override
3283     public void set(final long key, final double value, final boolean strict) {
3284         final int index = getArrayIndex(key);
3285 
3286         if (isValidArrayIndex(index)) {
3287             if (getArray().has(index)) {
3288                 setArray(getArray().set(index, value, strict));
3289             } else {
3290                 doesNotHave(index, value, strict);
3291             }
3292 
3293             return;
3294         }
3295 
3296         final String propName = JSType.toString(key);
3297         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3298     }
3299 
3300     @Override
3301     public void set(final long key, final Object value, final boolean strict) {
3302         final int index = getArrayIndex(key);
3303 
3304         if (isValidArrayIndex(index)) {
3305             if (getArray().has(index)) {
3306                 setArray(getArray().set(index, value, strict));
3307             } else {
3308                 doesNotHave(index, value, strict);
3309             }
3310 
3311             return;
3312         }
3313 
3314         final String propName = JSType.toString(key);
3315         setObject(findProperty(propName, true), strict, propName, value);
3316     }
3317 
3318     @Override
3319     public void set(final int key, final int value, final boolean strict) {
3320         final int index = getArrayIndex(key);
3321         if (isValidArrayIndex(index)) {
3322             if (getArray().has(index)) {
3323                 setArray(getArray().set(index, value, strict));
3324             } else {
3325                 doesNotHave(index, value, strict);
3326             }
3327             return;
3328         }
3329 
3330         final String propName = JSType.toString(key);
3331         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3332     }
3333 
3334     @Override
3335     public void set(final int key, final long value, final boolean strict) {
3336         final int index = getArrayIndex(key);
3337 
3338         if (isValidArrayIndex(index)) {
3339             if (getArray().has(index)) {
3340                 setArray(getArray().set(index, value, strict));
3341             } else {
3342                 doesNotHave(index, value, strict);
3343             }
3344 
3345             return;
3346         }
3347 
3348         final String propName = JSType.toString(key);
3349         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3350     }
3351 
3352     @Override
3353     public void set(final int key, final double value, final boolean strict) {
3354         final int index = getArrayIndex(key);
3355 
3356         if (isValidArrayIndex(index)) {
3357             if (getArray().has(index)) {
3358                 setArray(getArray().set(index, value, strict));
3359             } else {
3360                 doesNotHave(index, value, strict);
3361             }
3362 
3363             return;
3364         }
3365 
3366         final String propName = JSType.toString(key);
3367         setObject(findProperty(propName, true), strict, propName, JSType.toObject(value));
3368     }
3369 
3370     @Override
3371     public void set(final int key, final Object value, final boolean strict) {
3372         final int index = getArrayIndex(key);
3373 
3374         if (isValidArrayIndex(index)) {
3375             if (getArray().has(index)) {
3376                 setArray(getArray().set(index, value, strict));
3377             } else {
3378                 doesNotHave(index, value, strict);
3379             }
3380 
3381             return;
3382         }
3383 
3384         final String propName = JSType.toString(key);
3385         setObject(findProperty(propName, true), strict, propName, value);
3386     }
3387 
3388     @Override
3389     public boolean has(final Object key) {
3390         final Object primitiveKey = JSType.toPrimitive(key);
3391         final int    index        = getArrayIndex(primitiveKey);
3392         return isValidArrayIndex(index) ? hasArrayProperty(index) : hasProperty(JSType.toString(primitiveKey), true);
3393     }
3394 
3395     @Override
3396     public boolean has(final double key) {
3397         final int index = getArrayIndex(key);
3398         return isValidArrayIndex(index) ? hasArrayProperty(index) : hasProperty(JSType.toString(key), true);
3399     }
3400 
3401     @Override
3402     public boolean has(final long key) {
3403         final int index = getArrayIndex(key);
3404         return isValidArrayIndex(index) ? hasArrayProperty(index) : hasProperty(JSType.toString(key), true);
3405     }
3406 
3407     @Override
3408     public boolean has(final int key) {
3409         final int index = getArrayIndex(key);
3410         return isValidArrayIndex(index) ? hasArrayProperty(index) : hasProperty(JSType.toString(key), true);
3411     }
3412 
3413     private boolean hasArrayProperty(final int index) {
3414         boolean hasArrayKeys = false;
3415 
3416         for (ScriptObject self = this; self != null; self = self.getProto()) {
3417             if (self.getArray().has(index)) {
3418                 return true;
3419             }
3420             hasArrayKeys = hasArrayKeys || self.getMap().containsArrayKeys();
3421         }
3422 
3423         return hasArrayKeys && hasProperty(ArrayIndex.toKey(index), true);
3424     }
3425 
3426     @Override
3427     public boolean hasOwnProperty(final Object key) {
3428         final Object primitiveKey = JSType.toPrimitive(key, String.class);
3429         final int    index        = getArrayIndex(primitiveKey);
3430         return isValidArrayIndex(index) ? hasOwnArrayProperty(index) : hasProperty(JSType.toString(primitiveKey), false);
3431     }
3432 
3433     @Override
3434     public boolean hasOwnProperty(final int key) {
3435         final int index = getArrayIndex(key);
3436         return isValidArrayIndex(index) ? hasOwnArrayProperty(index) : hasProperty(JSType.toString(key), false);
3437     }
3438 
3439     @Override
3440     public boolean hasOwnProperty(final long key) {
3441         final int index = getArrayIndex(key);
3442         return isValidArrayIndex(index) ? hasOwnArrayProperty(index) : hasProperty(JSType.toString(key), false);
3443     }
3444 
3445     @Override
3446     public boolean hasOwnProperty(final double key) {
3447         final int index = getArrayIndex(key);
3448         return isValidArrayIndex(index) ? hasOwnArrayProperty(index) : hasProperty(JSType.toString(key), false);
3449     }
3450 
3451     private boolean hasOwnArrayProperty(final int index) {
3452         return getArray().has(index) || getMap().containsArrayKeys() && hasProperty(ArrayIndex.toKey(index), false);
3453     }
3454 
3455     @Override
3456     public boolean delete(final int key, final boolean strict) {
3457         final int index = getArrayIndex(key);
3458         final ArrayData array = getArray();
3459 
3460         if (array.has(index)) {
3461             if (array.canDelete(index, strict)) {
3462                 setArray(array.delete(index));
3463                 return true;
3464             }
3465             return false;
3466         }
3467 
3468         return deleteObject(JSType.toObject(key), strict);
3469     }
3470 
3471     @Override
3472     public boolean delete(final long key, final boolean strict) {
3473         final int index = getArrayIndex(key);
3474         final ArrayData array = getArray();
3475 
3476         if (array.has(index)) {
3477             if (array.canDelete(index, strict)) {
3478                 setArray(array.delete(index));
3479                 return true;
3480             }
3481             return false;
3482         }
3483 
3484         return deleteObject(JSType.toObject(key), strict);
3485     }
3486 
3487     @Override
3488     public boolean delete(final double key, final boolean strict) {
3489         final int index = getArrayIndex(key);
3490         final ArrayData array = getArray();
3491 
3492         if (array.has(index)) {
3493             if (array.canDelete(index, strict)) {
3494                 setArray(array.delete(index));
3495                 return true;
3496             }
3497             return false;
3498         }
3499 
3500         return deleteObject(JSType.toObject(key), strict);
3501     }
3502 
3503     @Override
3504     public boolean delete(final Object key, final boolean strict) {
3505         final Object    primitiveKey = JSType.toPrimitive(key, String.class);
3506         final int       index        = getArrayIndex(primitiveKey);
3507         final ArrayData array        = getArray();
3508 
3509         if (array.has(index)) {
3510             if (array.canDelete(index, strict)) {
3511                 setArray(array.delete(index));
3512                 return true;
3513             }
3514             return false;
3515         }
3516 
3517         return deleteObject(primitiveKey, strict);
3518     }
3519 
3520     private boolean deleteObject(final Object key, final boolean strict) {
3521         final String propName = JSType.toString(key);
3522         final FindProperty find = findProperty(propName, false);
3523 
3524         if (find == null) {
3525             return true;
3526         }
3527 
3528         if (!find.getProperty().isConfigurable()) {
3529             if (strict) {
3530                 throw typeError("cant.delete.property", propName, ScriptRuntime.safeToString(this));
3531             }
3532             return false;
3533         }
3534 
3535         final Property prop = find.getProperty();
3536         deleteOwnProperty(prop);
3537 
3538         return true;
3539     }
3540 
3541     /**
3542      * Make a new UserAccessorProperty property. getter and setter functions are stored in
3543      * this ScriptObject and slot values are used in property object.
3544      *
3545      * @param key the property name
3546      * @param propertyFlags attribute flags of the property
3547      * @param getter getter function for the property
3548      * @param setter setter function for the property
3549      * @return the newly created UserAccessorProperty
3550      */
3551     protected final UserAccessorProperty newUserAccessors(final String key, final int propertyFlags, final ScriptFunction getter, final ScriptFunction setter) {
3552         final UserAccessorProperty uc = getMap().newUserAccessors(key, propertyFlags);
3553         //property.getSetter(Object.class, getMap());
3554         uc.setAccessors(this, getMap(), new UserAccessorProperty.Accessors(getter, setter));
3555         return uc;
3556     }
3557 
3558     Object ensureSpillSize(final int slot) {
3559         if (slot < spillLength) {
3560             return this;
3561         }
3562         final int newLength = alignUp(slot + 1, SPILL_RATE);
3563         final Object[] newObjectSpill    = new Object[newLength];
3564         final long[]   newPrimitiveSpill = OBJECT_FIELDS_ONLY ? null : new long[newLength];
3565 
3566         if (objectSpill != null) {
3567             System.arraycopy(objectSpill, 0, newObjectSpill, 0, spillLength);
3568             if (!OBJECT_FIELDS_ONLY) {
3569                 System.arraycopy(primitiveSpill, 0, newPrimitiveSpill, 0, spillLength);
3570             }
3571         }
3572 
3573         this.primitiveSpill = newPrimitiveSpill;
3574         this.objectSpill    = newObjectSpill;
3575         this.spillLength = newLength;
3576 
3577         return this;
3578     }
3579 
3580     private static MethodHandle findOwnMH_V(final Class<? extends ScriptObject> clazz, final String name, final Class<?> rtype, final Class<?>... types) {
3581         // TODO: figure out how can it work for NativeArray$Prototype etc.
3582         return MH.findVirtual(MethodHandles.lookup(), ScriptObject.class, name, MH.type(rtype, types));
3583     }
3584 
3585     private static MethodHandle findOwnMH_V(final String name, final Class<?> rtype, final Class<?>... types) {
3586         return findOwnMH_V(ScriptObject.class, name, rtype, types);
3587     }
3588 
3589     private static MethodHandle findOwnMH_S(final String name, final Class<?> rtype, final Class<?>... types) {
3590         return MH.findStatic(MethodHandles.lookup(), ScriptObject.class, name, MH.type(rtype, types));
3591     }
3592 
3593     private static MethodHandle getKnownFunctionPropertyGuard(final PropertyMap map, final MethodHandle getter, final Object where, final ScriptFunction func) {
3594         return MH.insertArguments(KNOWNFUNCPROPGUARD, 1, map, getter, where, func);
3595     }
3596 
3597     @SuppressWarnings("unused")
3598     private static boolean knownFunctionPropertyGuard(final Object self, final PropertyMap map, final MethodHandle getter, final Object where, final ScriptFunction func) {
3599         if (self instanceof ScriptObject && ((ScriptObject)self).getMap() == map) {
3600             try {
3601                 return getter.invokeExact(where) == func;
3602             } catch (final RuntimeException | Error e) {
3603                 throw e;
3604             } catch (final Throwable t) {
3605                 throw new RuntimeException(t);
3606             }
3607         }
3608 
3609         return false;
3610     }
3611 
3612     /** This is updated only in debug mode - counts number of {@code ScriptObject} instances created */
3613     private static int count;
3614 
3615     /** This is updated only in debug mode - counts number of {@code ScriptObject} instances created that are scope */
3616     private static int scopeCount;
3617 
3618     /**
3619      * Get number of {@code ScriptObject} instances created. If not running in debug
3620      * mode this is always 0
3621      *
3622      * @return number of ScriptObjects created
3623      */
3624     public static int getCount() {
3625         return count;
3626     }
3627 
3628     /**
3629      * Get number of scope {@code ScriptObject} instances created. If not running in debug
3630      * mode this is always 0
3631      *
3632      * @return number of scope ScriptObjects created
3633      */
3634     public static int getScopeCount() {
3635         return scopeCount;
3636     }
3637 
3638 }