heap/SlotVisitorInlines.h

   1 /*
   2  * Copyright (C) 2012, 2013 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. AND ITS CONTRIBUTORS ``AS IS''
  14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  23  * THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef SlotVisitorInlines_h
  27 #define SlotVisitorInlines_h
  28
  29 #include "CopiedBlockInlines.h"
  30 #include "CopiedSpaceInlines.h"
  31 #include "Options.h"
  32 #include "SlotVisitor.h"
  33 #include "Weak.h"
  34 #include "WeakInlines.h"
  35
  36 namespace JSC {
  37
  38 ALWAYS_INLINE void SlotVisitor::append(JSValue* slot, size_t count)
  39 {
  40     for (size_t i = 0; i < count; ++i) {
  41         JSValue& value = slot[i];
  42         internalAppend(&value, value);
  43     }
  44 }
  45
  46 template<typename T>
  47 inline void SlotVisitor::appendUnbarrieredPointer(T** slot)
  48 {
  49     ASSERT(slot);
  50     JSCell* cell = *slot;
  51     internalAppend(slot, cell);
  52 }
  53
  54 template<typename T>
  55 inline void SlotVisitor::appendUnbarrieredReadOnlyPointer(T* cell)
  56 {
  57     internalAppend(0, cell);
  58 }
  59
  60 ALWAYS_INLINE void SlotVisitor::append(JSValue* slot)
  61 {
  62     ASSERT(slot);
  63     internalAppend(slot, *slot);
  64 }
  65
  66 ALWAYS_INLINE void SlotVisitor::appendUnbarrieredValue(JSValue* slot)
  67 {
  68     ASSERT(slot);
  69     internalAppend(slot, *slot);
  70 }
  71
  72 ALWAYS_INLINE void SlotVisitor::appendUnbarrieredReadOnlyValue(JSValue value)
  73 {
  74     internalAppend(0, value);
  75 }
  76
  77 ALWAYS_INLINE void SlotVisitor::append(JSCell** slot)
  78 {
  79     ASSERT(slot);
  80     internalAppend(slot, *slot);
  81 }
  82
  83 template<typename T>
  84 ALWAYS_INLINE void SlotVisitor::appendUnbarrieredWeak(Weak<T>* weak)
  85 {
  86     ASSERT(weak);
  87     if (weak->get())
  88         internalAppend(0, weak->get());
  89 }
  90
  91 ALWAYS_INLINE void SlotVisitor::internalAppend(void* from, JSValue value)
  92 {
  93     if (!value || !value.isCell())
  94         return;
  95     internalAppend(from, value.asCell());
  96 }
  97
  98 ALWAYS_INLINE void SlotVisitor::internalAppend(void* from, JSCell* cell)
  99 {
 100     ASSERT(!m_isCheckingForDefaultMarkViolation);
 101     if (!cell)
 102         return;
 103 #if ENABLE(ALLOCATION_LOGGING)
 104     dataLogF("JSC GC noticing reference from %p to %p.\n", from, cell);
 105 #else
 106     UNUSED_PARAM(from);
 107 #endif
 108 #if ENABLE(GC_VALIDATION)
 109     validate(cell);
 110 #endif
 111     if (Heap::testAndSetMarked(cell) || !cell->structure()) {
 112         ASSERT(cell->structure());
 113         return;
 114     }
 115
 116     cell->setMarked();
 117     m_bytesVisited += MarkedBlock::blockFor(cell)->cellSize();
 118
 119     unconditionallyAppend(cell);
 120 }
 121
 122 ALWAYS_INLINE void SlotVisitor::unconditionallyAppend(JSCell* cell)
 123 {
 124     ASSERT(Heap::isMarked(cell));
 125     m_visitCount++;
 126
 127     // Should never attempt to mark something that is zapped.
 128     ASSERT(!cell->isZapped());
 129
 130     m_stack.append(cell);
 131 }
 132
 133 template<typename T> inline void SlotVisitor::append(WriteBarrierBase<T>* slot)
 134 {
 135     internalAppend(slot, *slot->slot());
 136 }
 137
 138 template<typename Iterator> inline void SlotVisitor::append(Iterator begin, Iterator end)
 139 {
 140     for (auto it = begin; it != end; ++it)
 141         append(&*it);
 142 }
 143
 144 ALWAYS_INLINE void SlotVisitor::appendValues(WriteBarrierBase<Unknown>* barriers, size_t count)
 145 {
 146     append(barriers->slot(), count);
 147 }
 148
 149 inline void SlotVisitor::addWeakReferenceHarvester(WeakReferenceHarvester* weakReferenceHarvester)
 150 {
 151     m_shared.m_weakReferenceHarvesters.addThreadSafe(weakReferenceHarvester);
 152 }
 153
 154 inline void SlotVisitor::addUnconditionalFinalizer(UnconditionalFinalizer* unconditionalFinalizer)
 155 {
 156     m_shared.m_unconditionalFinalizers.addThreadSafe(unconditionalFinalizer);
 157 }
 158
 159 inline void SlotVisitor::addOpaqueRoot(void* root)
 160 {
 161 #if ENABLE(PARALLEL_GC)
 162     if (Options::numberOfGCMarkers() == 1) {
 163         // Put directly into the shared HashSet.
 164         m_shared.m_opaqueRoots.add(root);
 165         return;
 166     }
 167     // Put into the local set, but merge with the shared one every once in
 168     // a while to make sure that the local sets don't grow too large.
 169     mergeOpaqueRootsIfProfitable();
 170     m_opaqueRoots.add(root);
 171 #else
 172     m_opaqueRoots.add(root);
 173 #endif
 174 }
 175
 176 inline bool SlotVisitor::containsOpaqueRoot(void* root) const
 177 {
 178     ASSERT(!m_isInParallelMode);
 179 #if ENABLE(PARALLEL_GC)
 180     ASSERT(m_opaqueRoots.isEmpty());
 181     return m_shared.m_opaqueRoots.contains(root);
 182 #else
 183     return m_opaqueRoots.contains(root);
 184 #endif
 185 }
 186
 187 inline TriState SlotVisitor::containsOpaqueRootTriState(void* root) const
 188 {
 189     if (m_opaqueRoots.contains(root))
 190         return TrueTriState;
 191     std::lock_guard<std::mutex> lock(m_shared.m_opaqueRootsMutex);
 192     if (m_shared.m_opaqueRoots.contains(root))
 193         return TrueTriState;
 194     return MixedTriState;
 195 }
 196
 197 inline int SlotVisitor::opaqueRootCount()
 198 {
 199     ASSERT(!m_isInParallelMode);
 200 #if ENABLE(PARALLEL_GC)
 201     ASSERT(m_opaqueRoots.isEmpty());
 202     return m_shared.m_opaqueRoots.size();
 203 #else
 204     return m_opaqueRoots.size();
 205 #endif
 206 }
 207
 208 inline void SlotVisitor::mergeOpaqueRootsIfNecessary()
 209 {
 210     if (m_opaqueRoots.isEmpty())
 211         return;
 212     mergeOpaqueRoots();
 213 }
 214
 215 inline void SlotVisitor::mergeOpaqueRootsIfProfitable()
 216 {
 217     if (static_cast<unsigned>(m_opaqueRoots.size()) < Options::opaqueRootMergeThreshold())
 218         return;
 219     mergeOpaqueRoots();
 220 }
 221
 222 inline void SlotVisitor::donate()
 223 {
 224     ASSERT(m_isInParallelMode);
 225     if (Options::numberOfGCMarkers() == 1)
 226         return;
 227
 228     donateKnownParallel();
 229 }
 230
 231 inline void SlotVisitor::donateAndDrain()
 232 {
 233     donate();
 234     drain();
 235 }
 236
 237 inline void SlotVisitor::copyLater(JSCell* owner, CopyToken token, void* ptr, size_t bytes)
 238 {
 239     ASSERT(bytes);
 240     CopiedBlock* block = CopiedSpace::blockFor(ptr);
 241     if (block->isOversize()) {
 242         m_shared.m_copiedSpace->pin(block);
 243         return;
 244     }
 245
 246     ASSERT(heap()->m_storageSpace.contains(block));
 247
 248     SpinLockHolder locker(&block->workListLock());
 249     if (heap()->operationInProgress() == FullCollection || block->shouldReportLiveBytes(locker, owner)) {
 250         m_bytesCopied += bytes;
 251         block->reportLiveBytes(locker, owner, token, bytes);
 252     }
 253 }
 254
 255 inline void SlotVisitor::reportExtraMemoryUsage(JSCell* owner, size_t size)
 256 {
 257 #if ENABLE(GGC)
 258     // We don't want to double-count the extra memory that was reported in previous collections.
 259     if (heap()->operationInProgress() == EdenCollection && Heap::isRemembered(owner))
 260         return;
 261 #else
 262     UNUSED_PARAM(owner);
 263 #endif
 264
 265     size_t* counter = &m_shared.m_vm->heap.m_extraMemoryUsage;
 266
 267 #if ENABLE(COMPARE_AND_SWAP)
 268     for (;;) {
 269         size_t oldSize = *counter;
 270         if (WTF::weakCompareAndSwapSize(counter, oldSize, oldSize + size))
 271             return;
 272     }
 273 #else
 274     (*counter) += size;
 275 #endif
 276 }
 277
 278 inline Heap* SlotVisitor::heap() const
 279 {
 280     return &sharedData().m_vm->heap;
 281 }
 282
 283 inline VM& SlotVisitor::vm()
 284 {
 285     return *sharedData().m_vm;
 286 }
 287
 288 inline const VM& SlotVisitor::vm() const
 289 {
 290     return *sharedData().m_vm;
 291 }
 292
 293 } // namespace JSC
 294
 295 #endif // SlotVisitorInlines_h
 296