1  /*
 2   * Copyright (C) 2013, 2016 Apple Inc. All rights reserved.
 3   *
 4   * Redistribution and use in source and binary forms, with or without
 5   * modification, are permitted provided that the following conditions
 6   * are met:
 7   * 1. Redistributions of source code must retain the above copyright
 8   *    notice, this list of conditions and the following disclaimer.
 9   * 2. Redistributions in binary form must reproduce the above copyright
10   *    notice, this list of conditions and the following disclaimer in the
11   *    documentation and/or other materials provided with the distribution.
12   *
13   * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24   */
25  
26  #include "config.h"
27  #include "JSSet.h"
28  
29  #include "JSCInlines.h"
30  
31  namespace JSC {
32  
33  const ClassInfo JSSet::s_info = { "Set", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSSet) };
34  
35  JSSet* JSSet::clone(JSGlobalObject* globalObject, VM& vm, Structure* structure)
36  {
37      JSSet* instance = new (NotNull, allocateCell<JSSet>(vm.heap)) JSSet(vm, structure);
38      instance->finishCreation(globalObject, vm, this);
39      return instance;
40  }
41  
42  bool JSSet::isIteratorProtocolFastAndNonObservable()
43  {
44      JSGlobalObject* globalObject = this->globalObject();
45      if (!globalObject->isSetPrototypeIteratorProtocolFastAndNonObservable())
46          return false;
47  
48      VM& vm = globalObject->vm();
49      Structure* structure = this->structure(vm);
50      // This is the fast case. Many sets will be an original set.
51      if (structure == globalObject->setStructure())
52          return true;
53  
54      if (getPrototypeDirect(vm) != globalObject->jsSetPrototype())
55          return false;
56  
57      if (getDirectOffset(vm, vm.propertyNames->iteratorSymbol) != invalidOffset)
58          return false;
59  
60      return true;
61  }
62  
63  bool JSSet::canCloneFastAndNonObservable(Structure* structure)
64  {
65      auto addFastAndNonObservable = [&] (Structure* structure) {
66          JSGlobalObject* globalObject = structure->globalObject();
67          if (!globalObject->isSetPrototypeAddFastAndNonObservable())
68              return false;
69  
70          if (structure->hasPolyProto())
71              return false;
72  
73          if (structure->storedPrototype() != globalObject->jsSetPrototype())
74              return false;
75  
76          return true;
77      };
78  
79      return isIteratorProtocolFastAndNonObservable() && addFastAndNonObservable(structure);
80  }
81  
82  }