runtime/SparseArrayValueMap.cpp

   1 /*
   2  * Copyright (C) 2011, 2012 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 "SparseArrayValueMap.h"
  28
  29 #include "ClassInfo.h"
  30 #include "GetterSetter.h"
  31 #include "JSObject.h"
  32 #include "JSCInlines.h"
  33 #include "PropertySlot.h"
  34 #include "Reject.h"
  35 #include "SlotVisitor.h"
  36 #include "Structure.h"
  37
  38 namespace JSC {
  39
  40 const ClassInfo SparseArrayValueMap::s_info = { "SparseArrayValueMap", 0, 0, 0, CREATE_METHOD_TABLE(SparseArrayValueMap) };
  41
  42 SparseArrayValueMap::SparseArrayValueMap(VM& vm)
  43     : Base(vm, vm.sparseArrayValueMapStructure.get())
  44     , m_flags(Normal)
  45     , m_reportedCapacity(0)
  46 {
  47 }
  48
  49 SparseArrayValueMap::~SparseArrayValueMap()
  50 {
  51 }
  52
  53 void SparseArrayValueMap::finishCreation(VM& vm)
  54 {
  55     Base::finishCreation(vm);
  56 }
  57
  58 SparseArrayValueMap* SparseArrayValueMap::create(VM& vm)
  59 {
  60     SparseArrayValueMap* result = new (NotNull, allocateCell<SparseArrayValueMap>(vm.heap)) SparseArrayValueMap(vm);
  61     result->finishCreation(vm);
  62     return result;
  63 }
  64
  65 void SparseArrayValueMap::destroy(JSCell* cell)
  66 {
  67     static_cast<SparseArrayValueMap*>(cell)->SparseArrayValueMap::~SparseArrayValueMap();
  68 }
  69
  70 Structure* SparseArrayValueMap::createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
  71 {
  72     return Structure::create(vm, globalObject, prototype, TypeInfo(CompoundType, StructureFlags), info());
  73 }
  74
  75 SparseArrayValueMap::AddResult SparseArrayValueMap::add(JSObject* array, unsigned i)
  76 {
  77     SparseArrayEntry entry;
  78     entry.setWithoutWriteBarrier(jsUndefined());
  79
  80     AddResult result = m_map.add(i, entry);
  81     size_t capacity = m_map.capacity();
  82     if (capacity != m_reportedCapacity) {
  83         Heap::heap(array)->reportExtraMemoryCost((capacity - m_reportedCapacity) * (sizeof(unsigned) + sizeof(WriteBarrier<Unknown>)));
  84         m_reportedCapacity = capacity;
  85     }
  86     return result;
  87 }
  88
  89 void SparseArrayValueMap::putEntry(ExecState* exec, JSObject* array, unsigned i, JSValue value, bool shouldThrow)
  90 {
  91     AddResult result = add(array, i);
  92     SparseArrayEntry& entry = result.iterator->value;
  93
  94     // To save a separate find & add, we first always add to the sparse map.
  95     // In the uncommon case that this is a new property, and the array is not
  96     // extensible, this is not the right thing to have done - so remove again.
  97     if (result.isNewEntry && !array->isExtensible()) {
  98         remove(result.iterator);
  99         if (shouldThrow)
 100             throwTypeError(exec, StrictModeReadonlyPropertyWriteError);
 101         return;
 102     }
 103
 104     entry.put(exec, array, this, value, shouldThrow);
 105 }
 106
 107 bool SparseArrayValueMap::putDirect(ExecState* exec, JSObject* array, unsigned i, JSValue value, unsigned attributes, PutDirectIndexMode mode)
 108 {
 109     AddResult result = add(array, i);
 110     SparseArrayEntry& entry = result.iterator->value;
 111
 112     // To save a separate find & add, we first always add to the sparse map.
 113     // In the uncommon case that this is a new property, and the array is not
 114     // extensible, this is not the right thing to have done - so remove again.
 115     if (mode != PutDirectIndexLikePutDirect && result.isNewEntry && !array->isExtensible()) {
 116         remove(result.iterator);
 117         return reject(exec, mode == PutDirectIndexShouldThrow, "Attempting to define property on object that is not extensible.");
 118     }
 119
 120     entry.attributes = attributes;
 121     entry.set(exec->vm(), this, value);
 122     return true;
 123 }
 124
 125 void SparseArrayEntry::get(JSObject* thisObject, PropertySlot& slot) const
 126 {
 127     JSValue value = Base::get();
 128     ASSERT(value);
 129
 130     if (LIKELY(!value.isGetterSetter())) {
 131         slot.setValue(thisObject, attributes, value);
 132         return;
 133     }
 134
 135     slot.setGetterSlot(thisObject, attributes, jsCast<GetterSetter*>(value));
 136 }
 137
 138 void SparseArrayEntry::get(PropertyDescriptor& descriptor) const
 139 {
 140     descriptor.setDescriptor(Base::get(), attributes);
 141 }
 142
 143 JSValue SparseArrayEntry::get(ExecState* exec, JSObject* array) const
 144 {
 145     JSValue value = Base::get();
 146     ASSERT(value);
 147
 148     if (LIKELY(!value.isGetterSetter()))
 149         return value;
 150
 151     return callGetter(exec, array, jsCast<GetterSetter*>(value));
 152 }
 153
 154 void SparseArrayEntry::put(ExecState* exec, JSValue thisValue, SparseArrayValueMap* map, JSValue value, bool shouldThrow)
 155 {
 156     if (!(attributes & Accessor)) {
 157         if (attributes & ReadOnly) {
 158             if (shouldThrow)
 159                 throwTypeError(exec, StrictModeReadonlyPropertyWriteError);
 160             return;
 161         }
 162
 163         set(exec->vm(), map, value);
 164         return;
 165     }
 166
 167     callSetter(exec, thisValue, Base::get(), value, shouldThrow ? StrictMode : NotStrictMode);
 168 }
 169
 170 JSValue SparseArrayEntry::getNonSparseMode() const
 171 {
 172     ASSERT(!attributes);
 173     return Base::get();
 174 }
 175
 176 void SparseArrayValueMap::visitChildren(JSCell* thisObject, SlotVisitor& visitor)
 177 {
 178     Base::visitChildren(thisObject, visitor);
 179
 180     SparseArrayValueMap* thisMap = jsCast<SparseArrayValueMap*>(thisObject);
 181     iterator end = thisMap->m_map.end();
 182     for (iterator it = thisMap->m_map.begin(); it != end; ++it)
 183         visitor.append(&it->value);
 184 }
 185
 186 } // namespace JSC
 187