runtime/StructureInlines.h

   1 /*
   2  * Copyright (C) 2013, 2014 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 #ifndef StructureInlines_h
  27 #define StructureInlines_h
  28
  29 #include "JSArrayBufferView.h"
  30 #include "PropertyMapHashTable.h"
  31 #include "Structure.h"
  32
  33 namespace JSC {
  34
  35 inline Structure* Structure::create(VM& vm, JSGlobalObject* globalObject, JSValue prototype, const TypeInfo& typeInfo, const ClassInfo* classInfo, IndexingType indexingType, unsigned inlineCapacity)
  36 {
  37     ASSERT(vm.structureStructure);
  38     ASSERT(classInfo);
  39     Structure* structure = new (NotNull, allocateCell<Structure>(vm.heap)) Structure(vm, globalObject, prototype, typeInfo, classInfo, indexingType, inlineCapacity);
  40     structure->finishCreation(vm);
  41     return structure;
  42 }
  43
  44 inline Structure* Structure::createStructure(VM& vm)
  45 {
  46     ASSERT(!vm.structureStructure);
  47     Structure* structure = new (NotNull, allocateCell<Structure>(vm.heap)) Structure(vm);
  48     structure->finishCreation(vm, CreatingEarlyCell);
  49     return structure;
  50 }
  51
  52 inline Structure* Structure::create(VM& vm, Structure* structure)
  53 {
  54     ASSERT(vm.structureStructure);
  55     Structure* newStructure = new (NotNull, allocateCell<Structure>(vm.heap)) Structure(vm, structure);
  56     newStructure->finishCreation(vm);
  57     return newStructure;
  58 }
  59
  60 inline JSObject* Structure::storedPrototypeObject() const
  61 {
  62     JSValue value = m_prototype.get();
  63     if (value.isNull())
  64         return nullptr;
  65     return asObject(value);
  66 }
  67
  68 inline Structure* Structure::storedPrototypeStructure() const
  69 {
  70     JSObject* object = storedPrototypeObject();
  71     if (!object)
  72         return nullptr;
  73     return object->structure();
  74 }
  75
  76 ALWAYS_INLINE PropertyOffset Structure::get(VM& vm, PropertyName propertyName)
  77 {
  78     ASSERT(!isCompilationThread());
  79     ASSERT(structure()->classInfo() == info());
  80     PropertyTable* propertyTable;
  81     materializePropertyMapIfNecessary(vm, propertyTable);
  82     if (!propertyTable)
  83         return invalidOffset;
  84
  85     PropertyMapEntry* entry = propertyTable->get(propertyName.uid());
  86     return entry ? entry->offset : invalidOffset;
  87 }
  88
  89 ALWAYS_INLINE PropertyOffset Structure::get(VM& vm, PropertyName propertyName, unsigned& attributes)
  90 {
  91     ASSERT(!isCompilationThread());
  92     ASSERT(structure()->classInfo() == info());
  93
  94     PropertyTable* propertyTable;
  95     materializePropertyMapIfNecessary(vm, propertyTable);
  96     if (!propertyTable)
  97         return invalidOffset;
  98
  99     PropertyMapEntry* entry = propertyTable->get(propertyName.uid());
 100     if (!entry)
 101         return invalidOffset;
 102
 103     attributes = entry->attributes;
 104     return entry->offset;
 105 }
 106
 107 template<typename Functor>
 108 void Structure::forEachPropertyConcurrently(const Functor& functor)
 109 {
 110     Vector<Structure*, 8> structures;
 111     Structure* structure;
 112     PropertyTable* table;
 113
 114     findStructuresAndMapForMaterialization(structures, structure, table);
 115
 116     if (table) {
 117         for (auto& entry : *table) {
 118             if (!functor(entry)) {
 119                 structure->m_lock.unlock();
 120                 return;
 121             }
 122         }
 123         structure->m_lock.unlock();
 124     }
 125
 126     for (unsigned i = structures.size(); i--;) {
 127         structure = structures[i];
 128         if (!structure->m_nameInPrevious)
 129             continue;
 130
 131         if (!functor(PropertyMapEntry(structure->m_nameInPrevious.get(), structure->m_offset, structure->attributesInPrevious())))
 132             return;
 133     }
 134 }
 135
 136 inline PropertyOffset Structure::getConcurrently(UniquedStringImpl* uid)
 137 {
 138     unsigned attributesIgnored;
 139     return getConcurrently(uid, attributesIgnored);
 140 }
 141
 142 inline bool Structure::hasIndexingHeader(const JSCell* cell) const
 143 {
 144     if (hasIndexedProperties(indexingType()))
 145         return true;
 146
 147     if (!isTypedView(m_classInfo->typedArrayStorageType))
 148         return false;
 149
 150     return jsCast<const JSArrayBufferView*>(cell)->mode() == WastefulTypedArray;
 151 }
 152
 153 inline bool Structure::masqueradesAsUndefined(JSGlobalObject* lexicalGlobalObject)
 154 {
 155     return typeInfo().masqueradesAsUndefined() && globalObject() == lexicalGlobalObject;
 156 }
 157
 158 inline bool Structure::transitivelyTransitionedFrom(Structure* structureToFind)
 159 {
 160     for (Structure* current = this; current; current = current->previousID()) {
 161         if (current == structureToFind)
 162             return true;
 163     }
 164     return false;
 165 }
 166
 167 inline JSValue Structure::prototypeForLookup(JSGlobalObject* globalObject) const
 168 {
 169     if (isObject())
 170         return m_prototype.get();
 171     if (typeInfo().type() == SymbolType)
 172         return globalObject->symbolPrototype();
 173
 174     ASSERT(typeInfo().type() == StringType);
 175     return globalObject->stringPrototype();
 176 }
 177
 178 inline JSValue Structure::prototypeForLookup(ExecState* exec) const
 179 {
 180     return prototypeForLookup(exec->lexicalGlobalObject());
 181 }
 182
 183 inline StructureChain* Structure::prototypeChain(VM& vm, JSGlobalObject* globalObject) const
 184 {
 185     // We cache our prototype chain so our clients can share it.
 186     if (!isValid(globalObject, m_cachedPrototypeChain.get())) {
 187         JSValue prototype = prototypeForLookup(globalObject);
 188         m_cachedPrototypeChain.set(vm, this, StructureChain::create(vm, prototype.isNull() ? 0 : asObject(prototype)->structure()));
 189     }
 190     return m_cachedPrototypeChain.get();
 191 }
 192
 193 inline StructureChain* Structure::prototypeChain(ExecState* exec) const
 194 {
 195     return prototypeChain(exec->vm(), exec->lexicalGlobalObject());
 196 }
 197
 198 inline bool Structure::isValid(JSGlobalObject* globalObject, StructureChain* cachedPrototypeChain) const
 199 {
 200     if (!cachedPrototypeChain)
 201         return false;
 202
 203     JSValue prototype = prototypeForLookup(globalObject);
 204     WriteBarrier<Structure>* cachedStructure = cachedPrototypeChain->head();
 205     while (*cachedStructure && !prototype.isNull()) {
 206         if (asObject(prototype)->structure() != cachedStructure->get())
 207             return false;
 208         ++cachedStructure;
 209         prototype = asObject(prototype)->prototype();
 210     }
 211     return prototype.isNull() && !*cachedStructure;
 212 }
 213
 214 inline bool Structure::isValid(ExecState* exec, StructureChain* cachedPrototypeChain) const
 215 {
 216     return isValid(exec->lexicalGlobalObject(), cachedPrototypeChain);
 217 }
 218
 219 inline bool Structure::putWillGrowOutOfLineStorage()
 220 {
 221     checkOffsetConsistency();
 222
 223     ASSERT(outOfLineCapacity() >= outOfLineSize());
 224
 225     if (!propertyTable()) {
 226         unsigned currentSize = numberOfOutOfLineSlotsForLastOffset(m_offset);
 227         ASSERT(outOfLineCapacity() >= currentSize);
 228         return currentSize == outOfLineCapacity();
 229     }
 230
 231     ASSERT(totalStorageCapacity() >= propertyTable()->propertyStorageSize());
 232     if (propertyTable()->hasDeletedOffset())
 233         return false;
 234
 235     ASSERT(totalStorageCapacity() >= propertyTable()->size());
 236     return propertyTable()->size() == totalStorageCapacity();
 237 }
 238
 239 ALWAYS_INLINE WriteBarrier<PropertyTable>& Structure::propertyTable()
 240 {
 241     ASSERT(!globalObject() || !globalObject()->vm().heap.isCollecting());
 242     return m_propertyTableUnsafe;
 243 }
 244
 245 inline void Structure::didReplaceProperty(PropertyOffset offset)
 246 {
 247     if (LIKELY(!hasRareData()))
 248         return;
 249     StructureRareData::PropertyWatchpointMap* map = rareData()->m_replacementWatchpointSets.get();
 250     if (LIKELY(!map))
 251         return;
 252     WatchpointSet* set = map->get(offset);
 253     if (LIKELY(!set))
 254         return;
 255     set->fireAll("Property did get replaced");
 256 }
 257
 258 inline WatchpointSet* Structure::propertyReplacementWatchpointSet(PropertyOffset offset)
 259 {
 260     ConcurrentJITLocker locker(m_lock);
 261     if (!hasRareData())
 262         return nullptr;
 263     WTF::loadLoadFence();
 264     StructureRareData::PropertyWatchpointMap* map = rareData()->m_replacementWatchpointSets.get();
 265     if (!map)
 266         return nullptr;
 267     return map->get(offset);
 268 }
 269
 270 ALWAYS_INLINE bool Structure::checkOffsetConsistency() const
 271 {
 272     PropertyTable* propertyTable = m_propertyTableUnsafe.get();
 273
 274     if (!propertyTable) {
 275         ASSERT(!isPinnedPropertyTable());
 276         return true;
 277     }
 278
 279     // We cannot reliably assert things about the property table in the concurrent
 280     // compilation thread. It is possible for the table to be stolen and then have
 281     // things added to it, which leads to the offsets being all messed up. We could
 282     // get around this by grabbing a lock here, but I think that would be overkill.
 283     if (isCompilationThread())
 284         return true;
 285
 286     RELEASE_ASSERT(numberOfSlotsForLastOffset(m_offset, m_inlineCapacity) == propertyTable->propertyStorageSize());
 287     unsigned totalSize = propertyTable->propertyStorageSize();
 288     RELEASE_ASSERT((totalSize < inlineCapacity() ? 0 : totalSize - inlineCapacity()) == numberOfOutOfLineSlotsForLastOffset(m_offset));
 289
 290     return true;
 291 }
 292
 293 inline size_t nextOutOfLineStorageCapacity(size_t currentCapacity)
 294 {
 295     if (!currentCapacity)
 296         return initialOutOfLineCapacity;
 297     return currentCapacity * outOfLineGrowthFactor;
 298 }
 299
 300 inline size_t Structure::suggestedNewOutOfLineStorageCapacity()
 301 {
 302     return nextOutOfLineStorageCapacity(outOfLineCapacity());
 303 }
 304
 305 } // namespace JSC
 306
 307 #endif // StructureInlines_h
 308