src/v8/src/heap/heap-inl.h

   1 // Copyright 2012 the V8 project authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef V8_HEAP_HEAP_INL_H_
   6 #define V8_HEAP_HEAP_INL_H_
   7
   8 #include <cmath>
   9
  10 #include "src/base/platform/platform.h"
  11 #include "src/cpu-profiler.h"
  12 #include "src/heap/heap.h"
  13 #include "src/heap/store-buffer.h"
  14 #include "src/heap/store-buffer-inl.h"
  15 #include "src/heap-profiler.h"
  16 #include "src/isolate.h"
  17 #include "src/list-inl.h"
  18 #include "src/msan.h"
  19 #include "src/objects.h"
  20
  21 namespace v8 {
  22 namespace internal {
  23
  24 void PromotionQueue::insert(HeapObject* target, int size) {
  25   if (emergency_stack_ != NULL) {
  26     emergency_stack_->Add(Entry(target, size));
  27     return;
  28   }
  29
  30   if (NewSpacePage::IsAtStart(reinterpret_cast<Address>(rear_))) {
  31     NewSpacePage* rear_page =
  32         NewSpacePage::FromAddress(reinterpret_cast<Address>(rear_));
  33     DCHECK(!rear_page->prev_page()->is_anchor());
  34     rear_ = reinterpret_cast<intptr_t*>(rear_page->prev_page()->area_end());
  35   }
  36
  37   if ((rear_ - 2) < limit_) {
  38     RelocateQueueHead();
  39     emergency_stack_->Add(Entry(target, size));
  40     return;
  41   }
  42
  43   *(--rear_) = reinterpret_cast<intptr_t>(target);
  44   *(--rear_) = size;
  45 // Assert no overflow into live objects.
  46 #ifdef DEBUG
  47   SemiSpace::AssertValidRange(target->GetIsolate()->heap()->new_space()->top(),
  48                               reinterpret_cast<Address>(rear_));
  49 #endif
  50 }
  51
  52
  53 template <>
  54 bool inline Heap::IsOneByte(Vector<const char> str, int chars) {
  55   // TODO(dcarney): incorporate Latin-1 check when Latin-1 is supported?
  56   return chars == str.length();
  57 }
  58
  59
  60 template <>
  61 bool inline Heap::IsOneByte(String* str, int chars) {
  62   return str->IsOneByteRepresentation();
  63 }
  64
  65
  66 AllocationResult Heap::AllocateInternalizedStringFromUtf8(
  67     Vector<const char> str, int chars, uint32_t hash_field) {
  68   if (IsOneByte(str, chars)) {
  69     return AllocateOneByteInternalizedString(Vector<const uint8_t>::cast(str),
  70                                              hash_field);
  71   }
  72   return AllocateInternalizedStringImpl<false>(str, chars, hash_field);
  73 }
  74
  75
  76 template <typename T>
  77 AllocationResult Heap::AllocateInternalizedStringImpl(T t, int chars,
  78                                                       uint32_t hash_field) {
  79   if (IsOneByte(t, chars)) {
  80     return AllocateInternalizedStringImpl<true>(t, chars, hash_field);
  81   }
  82   return AllocateInternalizedStringImpl<false>(t, chars, hash_field);
  83 }
  84
  85
  86 AllocationResult Heap::AllocateOneByteInternalizedString(
  87     Vector<const uint8_t> str, uint32_t hash_field) {
  88   CHECK_GE(String::kMaxLength, str.length());
  89   // Compute map and object size.
  90   Map* map = one_byte_internalized_string_map();
  91   int size = SeqOneByteString::SizeFor(str.length());
  92   AllocationSpace space = SelectSpace(size, OLD_DATA_SPACE, TENURED);
  93
  94   // Allocate string.
  95   HeapObject* result;
  96   {
  97     AllocationResult allocation = AllocateRaw(size, space, OLD_DATA_SPACE);
  98     if (!allocation.To(&result)) return allocation;
  99   }
 100
 101   // String maps are all immortal immovable objects.
 102   result->set_map_no_write_barrier(map);
 103   // Set length and hash fields of the allocated string.
 104   String* answer = String::cast(result);
 105   answer->set_length(str.length());
 106   answer->set_hash_field(hash_field);
 107
 108   DCHECK_EQ(size, answer->Size());
 109
 110   // Fill in the characters.
 111   MemCopy(answer->address() + SeqOneByteString::kHeaderSize, str.start(),
 112           str.length());
 113
 114   return answer;
 115 }
 116
 117
 118 AllocationResult Heap::AllocateTwoByteInternalizedString(Vector<const uc16> str,
 119                                                          uint32_t hash_field) {
 120   CHECK_GE(String::kMaxLength, str.length());
 121   // Compute map and object size.
 122   Map* map = internalized_string_map();
 123   int size = SeqTwoByteString::SizeFor(str.length());
 124   AllocationSpace space = SelectSpace(size, OLD_DATA_SPACE, TENURED);
 125
 126   // Allocate string.
 127   HeapObject* result;
 128   {
 129     AllocationResult allocation = AllocateRaw(size, space, OLD_DATA_SPACE);
 130     if (!allocation.To(&result)) return allocation;
 131   }
 132
 133   result->set_map(map);
 134   // Set length and hash fields of the allocated string.
 135   String* answer = String::cast(result);
 136   answer->set_length(str.length());
 137   answer->set_hash_field(hash_field);
 138
 139   DCHECK_EQ(size, answer->Size());
 140
 141   // Fill in the characters.
 142   MemCopy(answer->address() + SeqTwoByteString::kHeaderSize, str.start(),
 143           str.length() * kUC16Size);
 144
 145   return answer;
 146 }
 147
 148 AllocationResult Heap::CopyFixedArray(FixedArray* src) {
 149   if (src->length() == 0) return src;
 150   return CopyFixedArrayWithMap(src, src->map());
 151 }
 152
 153
 154 AllocationResult Heap::CopyFixedDoubleArray(FixedDoubleArray* src) {
 155   if (src->length() == 0) return src;
 156   return CopyFixedDoubleArrayWithMap(src, src->map());
 157 }
 158
 159
 160 AllocationResult Heap::CopyConstantPoolArray(ConstantPoolArray* src) {
 161   if (src->length() == 0) return src;
 162   return CopyConstantPoolArrayWithMap(src, src->map());
 163 }
 164
 165
 166 AllocationResult Heap::AllocateRaw(int size_in_bytes, AllocationSpace space,
 167                                    AllocationSpace retry_space) {
 168   DCHECK(AllowHandleAllocation::IsAllowed());
 169   DCHECK(AllowHeapAllocation::IsAllowed());
 170   DCHECK(gc_state_ == NOT_IN_GC);
 171 #ifdef DEBUG
 172   if (FLAG_gc_interval >= 0 && AllowAllocationFailure::IsAllowed(isolate_) &&
 173       Heap::allocation_timeout_-- <= 0) {
 174     return AllocationResult::Retry(space);
 175   }
 176   isolate_->counters()->objs_since_last_full()->Increment();
 177   isolate_->counters()->objs_since_last_young()->Increment();
 178 #endif
 179
 180   HeapObject* object;
 181   AllocationResult allocation;
 182   if (NEW_SPACE == space) {
 183     allocation = new_space_.AllocateRaw(size_in_bytes);
 184     if (always_allocate() && allocation.IsRetry() && retry_space != NEW_SPACE) {
 185       space = retry_space;
 186     } else {
 187       if (allocation.To(&object)) {
 188         OnAllocationEvent(object, size_in_bytes);
 189       }
 190       return allocation;
 191     }
 192   }
 193
 194   if (OLD_POINTER_SPACE == space) {
 195     allocation = old_pointer_space_->AllocateRaw(size_in_bytes);
 196   } else if (OLD_DATA_SPACE == space) {
 197     allocation = old_data_space_->AllocateRaw(size_in_bytes);
 198   } else if (CODE_SPACE == space) {
 199     if (size_in_bytes <= code_space()->AreaSize()) {
 200       allocation = code_space_->AllocateRaw(size_in_bytes);
 201     } else {
 202       // Large code objects are allocated in large object space.
 203       allocation = lo_space_->AllocateRaw(size_in_bytes, EXECUTABLE);
 204     }
 205   } else if (LO_SPACE == space) {
 206     allocation = lo_space_->AllocateRaw(size_in_bytes, NOT_EXECUTABLE);
 207   } else if (CELL_SPACE == space) {
 208     allocation = cell_space_->AllocateRaw(size_in_bytes);
 209   } else if (PROPERTY_CELL_SPACE == space) {
 210     allocation = property_cell_space_->AllocateRaw(size_in_bytes);
 211   } else {
 212     DCHECK(MAP_SPACE == space);
 213     allocation = map_space_->AllocateRaw(size_in_bytes);
 214   }
 215   if (allocation.To(&object)) {
 216     OnAllocationEvent(object, size_in_bytes);
 217   } else {
 218     old_gen_exhausted_ = true;
 219   }
 220   return allocation;
 221 }
 222
 223
 224 void Heap::OnAllocationEvent(HeapObject* object, int size_in_bytes) {
 225   HeapProfiler* profiler = isolate_->heap_profiler();
 226   if (profiler->is_tracking_allocations()) {
 227     profiler->AllocationEvent(object->address(), size_in_bytes);
 228   }
 229
 230   if (FLAG_verify_predictable) {
 231     ++allocations_count_;
 232
 233     UpdateAllocationsHash(object);
 234     UpdateAllocationsHash(size_in_bytes);
 235
 236     if ((FLAG_dump_allocations_digest_at_alloc > 0) &&
 237         (--dump_allocations_hash_countdown_ == 0)) {
 238       dump_allocations_hash_countdown_ = FLAG_dump_allocations_digest_at_alloc;
 239       PrintAlloctionsHash();
 240     }
 241   }
 242 }
 243
 244
 245 void Heap::OnMoveEvent(HeapObject* target, HeapObject* source,
 246                        int size_in_bytes) {
 247   HeapProfiler* heap_profiler = isolate_->heap_profiler();
 248   if (heap_profiler->is_tracking_object_moves()) {
 249     heap_profiler->ObjectMoveEvent(source->address(), target->address(),
 250                                    size_in_bytes);
 251   }
 252
 253   if (isolate_->logger()->is_logging_code_events() ||
 254       isolate_->cpu_profiler()->is_profiling()) {
 255     if (target->IsSharedFunctionInfo()) {
 256       PROFILE(isolate_, SharedFunctionInfoMoveEvent(source->address(),
 257                                                     target->address()));
 258     }
 259   }
 260
 261   if (FLAG_verify_predictable) {
 262     ++allocations_count_;
 263
 264     UpdateAllocationsHash(source);
 265     UpdateAllocationsHash(target);
 266     UpdateAllocationsHash(size_in_bytes);
 267
 268     if ((FLAG_dump_allocations_digest_at_alloc > 0) &&
 269         (--dump_allocations_hash_countdown_ == 0)) {
 270       dump_allocations_hash_countdown_ = FLAG_dump_allocations_digest_at_alloc;
 271       PrintAlloctionsHash();
 272     }
 273   }
 274 }
 275
 276
 277 void Heap::UpdateAllocationsHash(HeapObject* object) {
 278   Address object_address = object->address();
 279   MemoryChunk* memory_chunk = MemoryChunk::FromAddress(object_address);
 280   AllocationSpace allocation_space = memory_chunk->owner()->identity();
 281
 282   STATIC_ASSERT(kSpaceTagSize + kPageSizeBits <= 32);
 283   uint32_t value =
 284       static_cast<uint32_t>(object_address - memory_chunk->address()) |
 285       (static_cast<uint32_t>(allocation_space) << kPageSizeBits);
 286
 287   UpdateAllocationsHash(value);
 288 }
 289
 290
 291 void Heap::UpdateAllocationsHash(uint32_t value) {
 292   uint16_t c1 = static_cast<uint16_t>(value);
 293   uint16_t c2 = static_cast<uint16_t>(value >> 16);
 294   raw_allocations_hash_ =
 295       StringHasher::AddCharacterCore(raw_allocations_hash_, c1);
 296   raw_allocations_hash_ =
 297       StringHasher::AddCharacterCore(raw_allocations_hash_, c2);
 298 }
 299
 300
 301 void Heap::PrintAlloctionsHash() {
 302   uint32_t hash = StringHasher::GetHashCore(raw_allocations_hash_);
 303   PrintF("\n### Allocations = %u, hash = 0x%08x\n", allocations_count_, hash);
 304 }
 305
 306
 307 void Heap::FinalizeExternalString(String* string) {
 308   DCHECK(string->IsExternalString());
 309   v8::String::ExternalStringResourceBase** resource_addr =
 310       reinterpret_cast<v8::String::ExternalStringResourceBase**>(
 311           reinterpret_cast<byte*>(string) + ExternalString::kResourceOffset -
 312           kHeapObjectTag);
 313
 314   // Dispose of the C++ object if it has not already been disposed.
 315   if (*resource_addr != NULL) {
 316     (*resource_addr)->Dispose();
 317     *resource_addr = NULL;
 318   }
 319 }
 320
 321
 322 bool Heap::InNewSpace(Object* object) {
 323   bool result = new_space_.Contains(object);
 324   DCHECK(!result ||                 // Either not in new space
 325          gc_state_ != NOT_IN_GC ||  // ... or in the middle of GC
 326          InToSpace(object));        // ... or in to-space (where we allocate).
 327   return result;
 328 }
 329
 330
 331 bool Heap::InNewSpace(Address address) { return new_space_.Contains(address); }
 332
 333
 334 bool Heap::InFromSpace(Object* object) {
 335   return new_space_.FromSpaceContains(object);
 336 }
 337
 338
 339 bool Heap::InToSpace(Object* object) {
 340   return new_space_.ToSpaceContains(object);
 341 }
 342
 343
 344 bool Heap::InOldPointerSpace(Address address) {
 345   return old_pointer_space_->Contains(address);
 346 }
 347
 348
 349 bool Heap::InOldPointerSpace(Object* object) {
 350   return InOldPointerSpace(reinterpret_cast<Address>(object));
 351 }
 352
 353
 354 bool Heap::InOldDataSpace(Address address) {
 355   return old_data_space_->Contains(address);
 356 }
 357
 358
 359 bool Heap::InOldDataSpace(Object* object) {
 360   return InOldDataSpace(reinterpret_cast<Address>(object));
 361 }
 362
 363
 364 bool Heap::OldGenerationAllocationLimitReached() {
 365   if (!incremental_marking()->IsStopped()) return false;
 366   return OldGenerationSpaceAvailable() < 0;
 367 }
 368
 369
 370 bool Heap::ShouldBePromoted(Address old_address, int object_size) {
 371   NewSpacePage* page = NewSpacePage::FromAddress(old_address);
 372   Address age_mark = new_space_.age_mark();
 373   return page->IsFlagSet(MemoryChunk::NEW_SPACE_BELOW_AGE_MARK) &&
 374          (!page->ContainsLimit(age_mark) || old_address < age_mark);
 375 }
 376
 377
 378 void Heap::RecordWrite(Address address, int offset) {
 379   if (!InNewSpace(address)) store_buffer_.Mark(address + offset);
 380 }
 381
 382
 383 void Heap::RecordWrites(Address address, int start, int len) {
 384   if (!InNewSpace(address)) {
 385     for (int i = 0; i < len; i++) {
 386       store_buffer_.Mark(address + start + i * kPointerSize);
 387     }
 388   }
 389 }
 390
 391
 392 OldSpace* Heap::TargetSpace(HeapObject* object) {
 393   InstanceType type = object->map()->instance_type();
 394   AllocationSpace space = TargetSpaceId(type);
 395   return (space == OLD_POINTER_SPACE) ? old_pointer_space_ : old_data_space_;
 396 }
 397
 398
 399 AllocationSpace Heap::TargetSpaceId(InstanceType type) {
 400   // Heap numbers and sequential strings are promoted to old data space, all
 401   // other object types are promoted to old pointer space.  We do not use
 402   // object->IsHeapNumber() and object->IsSeqString() because we already
 403   // know that object has the heap object tag.
 404
 405   // These objects are never allocated in new space.
 406   DCHECK(type != MAP_TYPE);
 407   DCHECK(type != CODE_TYPE);
 408   DCHECK(type != ODDBALL_TYPE);
 409   DCHECK(type != CELL_TYPE);
 410   DCHECK(type != PROPERTY_CELL_TYPE);
 411
 412   if (type <= LAST_NAME_TYPE) {
 413     if (type == SYMBOL_TYPE) return OLD_POINTER_SPACE;
 414     DCHECK(type < FIRST_NONSTRING_TYPE);
 415     // There are four string representations: sequential strings, external
 416     // strings, cons strings, and sliced strings.
 417     // Only the latter two contain non-map-word pointers to heap objects.
 418     return ((type & kIsIndirectStringMask) == kIsIndirectStringTag)
 419                ? OLD_POINTER_SPACE
 420                : OLD_DATA_SPACE;
 421   } else {
 422     return (type <= LAST_DATA_TYPE) ? OLD_DATA_SPACE : OLD_POINTER_SPACE;
 423   }
 424 }
 425
 426
 427 bool Heap::AllowedToBeMigrated(HeapObject* obj, AllocationSpace dst) {
 428   // Object migration is governed by the following rules:
 429   //
 430   // 1) Objects in new-space can be migrated to one of the old spaces
 431   //    that matches their target space or they stay in new-space.
 432   // 2) Objects in old-space stay in the same space when migrating.
 433   // 3) Fillers (two or more words) can migrate due to left-trimming of
 434   //    fixed arrays in new-space, old-data-space and old-pointer-space.
 435   // 4) Fillers (one word) can never migrate, they are skipped by
 436   //    incremental marking explicitly to prevent invalid pattern.
 437   // 5) Short external strings can end up in old pointer space when a cons
 438   //    string in old pointer space is made external (String::MakeExternal).
 439   //
 440   // Since this function is used for debugging only, we do not place
 441   // asserts here, but check everything explicitly.
 442   if (obj->map() == one_pointer_filler_map()) return false;
 443   InstanceType type = obj->map()->instance_type();
 444   MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address());
 445   AllocationSpace src = chunk->owner()->identity();
 446   switch (src) {
 447     case NEW_SPACE:
 448       return dst == src || dst == TargetSpaceId(type);
 449     case OLD_POINTER_SPACE:
 450       return dst == src && (dst == TargetSpaceId(type) || obj->IsFiller() ||
 451                             obj->IsExternalString());
 452     case OLD_DATA_SPACE:
 453       return dst == src && dst == TargetSpaceId(type);
 454     case CODE_SPACE:
 455       return dst == src && type == CODE_TYPE;
 456     case MAP_SPACE:
 457     case CELL_SPACE:
 458     case PROPERTY_CELL_SPACE:
 459     case LO_SPACE:
 460       return false;
 461   }
 462   UNREACHABLE();
 463   return false;
 464 }
 465
 466
 467 void Heap::CopyBlock(Address dst, Address src, int byte_size) {
 468   CopyWords(reinterpret_cast<Object**>(dst), reinterpret_cast<Object**>(src),
 469             static_cast<size_t>(byte_size / kPointerSize));
 470 }
 471
 472
 473 void Heap::MoveBlock(Address dst, Address src, int byte_size) {
 474   DCHECK(IsAligned(byte_size, kPointerSize));
 475
 476   int size_in_words = byte_size / kPointerSize;
 477
 478   if ((dst < src) || (dst >= (src + byte_size))) {
 479     Object** src_slot = reinterpret_cast<Object**>(src);
 480     Object** dst_slot = reinterpret_cast<Object**>(dst);
 481     Object** end_slot = src_slot + size_in_words;
 482
 483     while (src_slot != end_slot) {
 484       *dst_slot++ = *src_slot++;
 485     }
 486   } else {
 487     MemMove(dst, src, static_cast<size_t>(byte_size));
 488   }
 489 }
 490
 491
 492 void Heap::ScavengePointer(HeapObject** p) { ScavengeObject(p, *p); }
 493
 494
 495 AllocationMemento* Heap::FindAllocationMemento(HeapObject* object) {
 496   // Check if there is potentially a memento behind the object. If
 497   // the last word of the memento is on another page we return
 498   // immediately.
 499   Address object_address = object->address();
 500   Address memento_address = object_address + object->Size();
 501   Address last_memento_word_address = memento_address + kPointerSize;
 502   if (!NewSpacePage::OnSamePage(object_address, last_memento_word_address)) {
 503     return NULL;
 504   }
 505
 506   HeapObject* candidate = HeapObject::FromAddress(memento_address);
 507   Map* candidate_map = candidate->map();
 508   // This fast check may peek at an uninitialized word. However, the slow check
 509   // below (memento_address == top) ensures that this is safe. Mark the word as
 510   // initialized to silence MemorySanitizer warnings.
 511   MSAN_MEMORY_IS_INITIALIZED(&candidate_map, sizeof(candidate_map));
 512   if (candidate_map != allocation_memento_map()) return NULL;
 513
 514   // Either the object is the last object in the new space, or there is another
 515   // object of at least word size (the header map word) following it, so
 516   // suffices to compare ptr and top here. Note that technically we do not have
 517   // to compare with the current top pointer of the from space page during GC,
 518   // since we always install filler objects above the top pointer of a from
 519   // space page when performing a garbage collection. However, always performing
 520   // the test makes it possible to have a single, unified version of
 521   // FindAllocationMemento that is used both by the GC and the mutator.
 522   Address top = NewSpaceTop();
 523   DCHECK(memento_address == top ||
 524          memento_address + HeapObject::kHeaderSize <= top ||
 525          !NewSpacePage::OnSamePage(memento_address, top));
 526   if (memento_address == top) return NULL;
 527
 528   AllocationMemento* memento = AllocationMemento::cast(candidate);
 529   if (!memento->IsValid()) return NULL;
 530   return memento;
 531 }
 532
 533
 534 void Heap::UpdateAllocationSiteFeedback(HeapObject* object,
 535                                         ScratchpadSlotMode mode) {
 536   Heap* heap = object->GetHeap();
 537   DCHECK(heap->InFromSpace(object));
 538
 539   if (!FLAG_allocation_site_pretenuring ||
 540       !AllocationSite::CanTrack(object->map()->instance_type()))
 541     return;
 542
 543   AllocationMemento* memento = heap->FindAllocationMemento(object);
 544   if (memento == NULL) return;
 545
 546   if (memento->GetAllocationSite()->IncrementMementoFoundCount()) {
 547     heap->AddAllocationSiteToScratchpad(memento->GetAllocationSite(), mode);
 548   }
 549 }
 550
 551
 552 void Heap::ScavengeObject(HeapObject** p, HeapObject* object) {
 553   DCHECK(object->GetIsolate()->heap()->InFromSpace(object));
 554
 555   // We use the first word (where the map pointer usually is) of a heap
 556   // object to record the forwarding pointer.  A forwarding pointer can
 557   // point to an old space, the code space, or the to space of the new
 558   // generation.
 559   MapWord first_word = object->map_word();
 560
 561   // If the first word is a forwarding address, the object has already been
 562   // copied.
 563   if (first_word.IsForwardingAddress()) {
 564     HeapObject* dest = first_word.ToForwardingAddress();
 565     DCHECK(object->GetIsolate()->heap()->InFromSpace(*p));
 566     *p = dest;
 567     return;
 568   }
 569
 570   UpdateAllocationSiteFeedback(object, IGNORE_SCRATCHPAD_SLOT);
 571
 572   // AllocationMementos are unrooted and shouldn't survive a scavenge
 573   DCHECK(object->map() != object->GetHeap()->allocation_memento_map());
 574   // Call the slow part of scavenge object.
 575   return ScavengeObjectSlow(p, object);
 576 }
 577
 578
 579 bool Heap::CollectGarbage(AllocationSpace space, const char* gc_reason,
 580                           const v8::GCCallbackFlags callbackFlags) {
 581   const char* collector_reason = NULL;
 582   GarbageCollector collector = SelectGarbageCollector(space, &collector_reason);
 583   return CollectGarbage(collector, gc_reason, collector_reason, callbackFlags);
 584 }
 585
 586
 587 Isolate* Heap::isolate() {
 588   return reinterpret_cast<Isolate*>(
 589       reinterpret_cast<intptr_t>(this) -
 590       reinterpret_cast<size_t>(reinterpret_cast<Isolate*>(4)->heap()) + 4);
 591 }
 592
 593
 594 // Calls the FUNCTION_CALL function and retries it up to three times
 595 // to guarantee that any allocations performed during the call will
 596 // succeed if there's enough memory.
 597
 598 // Warning: Do not use the identifiers __object__, __maybe_object__ or
 599 // __scope__ in a call to this macro.
 600
 601 #define RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE) \
 602   if (__allocation__.To(&__object__)) {                   \
 603     DCHECK(__object__ != (ISOLATE)->heap()->exception()); \
 604     RETURN_VALUE;                                         \
 605   }
 606
 607 #define CALL_AND_RETRY(ISOLATE, FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY)    \
 608   do {                                                                        \
 609     AllocationResult __allocation__ = FUNCTION_CALL;                          \
 610     Object* __object__ = NULL;                                                \
 611     RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE)                         \
 612     (ISOLATE)->heap()->CollectGarbage(__allocation__.RetrySpace(),            \
 613                                       "allocation failure");                  \
 614     __allocation__ = FUNCTION_CALL;                                           \
 615     RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE)                         \
 616     (ISOLATE)->counters()->gc_last_resort_from_handles()->Increment();        \
 617     (ISOLATE)->heap()->CollectAllAvailableGarbage("last resort gc");          \
 618     {                                                                         \
 619       AlwaysAllocateScope __scope__(ISOLATE);                                 \
 620       __allocation__ = FUNCTION_CALL;                                         \
 621     }                                                                         \
 622     RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE)                         \
 623     /* TODO(1181417): Fix this. */                                            \
 624     v8::internal::Heap::FatalProcessOutOfMemory("CALL_AND_RETRY_LAST", true); \
 625     RETURN_EMPTY;                                                             \
 626   } while (false)
 627
 628 #define CALL_AND_RETRY_OR_DIE(ISOLATE, FUNCTION_CALL, RETURN_VALUE, \
 629                               RETURN_EMPTY)                         \
 630   CALL_AND_RETRY(ISOLATE, FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY)
 631
 632 #define CALL_HEAP_FUNCTION(ISOLATE, FUNCTION_CALL, TYPE)                      \
 633   CALL_AND_RETRY_OR_DIE(ISOLATE, FUNCTION_CALL,                               \
 634                         return Handle<TYPE>(TYPE::cast(__object__), ISOLATE), \
 635                         return Handle<TYPE>())
 636
 637
 638 #define CALL_HEAP_FUNCTION_VOID(ISOLATE, FUNCTION_CALL) \
 639   CALL_AND_RETRY_OR_DIE(ISOLATE, FUNCTION_CALL, return, return)
 640
 641
 642 void ExternalStringTable::AddString(String* string) {
 643   DCHECK(string->IsExternalString());
 644   if (heap_->InNewSpace(string)) {
 645     new_space_strings_.Add(string);
 646   } else {
 647     old_space_strings_.Add(string);
 648   }
 649 }
 650
 651
 652 void ExternalStringTable::Iterate(ObjectVisitor* v) {
 653   if (!new_space_strings_.is_empty()) {
 654     Object** start = &new_space_strings_[0];
 655     v->VisitPointers(start, start + new_space_strings_.length());
 656   }
 657   if (!old_space_strings_.is_empty()) {
 658     Object** start = &old_space_strings_[0];
 659     v->VisitPointers(start, start + old_space_strings_.length());
 660   }
 661 }
 662
 663
 664 // Verify() is inline to avoid ifdef-s around its calls in release
 665 // mode.
 666 void ExternalStringTable::Verify() {
 667 #ifdef DEBUG
 668   for (int i = 0; i < new_space_strings_.length(); ++i) {
 669     Object* obj = Object::cast(new_space_strings_[i]);
 670     DCHECK(heap_->InNewSpace(obj));
 671     DCHECK(obj != heap_->the_hole_value());
 672   }
 673   for (int i = 0; i < old_space_strings_.length(); ++i) {
 674     Object* obj = Object::cast(old_space_strings_[i]);
 675     DCHECK(!heap_->InNewSpace(obj));
 676     DCHECK(obj != heap_->the_hole_value());
 677   }
 678 #endif
 679 }
 680
 681
 682 void ExternalStringTable::AddOldString(String* string) {
 683   DCHECK(string->IsExternalString());
 684   DCHECK(!heap_->InNewSpace(string));
 685   old_space_strings_.Add(string);
 686 }
 687
 688
 689 void ExternalStringTable::ShrinkNewStrings(int position) {
 690   new_space_strings_.Rewind(position);
 691 #ifdef VERIFY_HEAP
 692   if (FLAG_verify_heap) {
 693     Verify();
 694   }
 695 #endif
 696 }
 697
 698
 699 void Heap::ClearInstanceofCache() {
 700   set_instanceof_cache_function(Smi::FromInt(0));
 701 }
 702
 703
 704 Object* Heap::ToBoolean(bool condition) {
 705   return condition ? true_value() : false_value();
 706 }
 707
 708
 709 void Heap::CompletelyClearInstanceofCache() {
 710   set_instanceof_cache_map(Smi::FromInt(0));
 711   set_instanceof_cache_function(Smi::FromInt(0));
 712 }
 713
 714
 715 AlwaysAllocateScope::AlwaysAllocateScope(Isolate* isolate)
 716     : heap_(isolate->heap()), daf_(isolate) {
 717   // We shouldn't hit any nested scopes, because that requires
 718   // non-handle code to call handle code. The code still works but
 719   // performance will degrade, so we want to catch this situation
 720   // in debug mode.
 721   DCHECK(heap_->always_allocate_scope_depth_ == 0);
 722   heap_->always_allocate_scope_depth_++;
 723 }
 724
 725
 726 AlwaysAllocateScope::~AlwaysAllocateScope() {
 727   heap_->always_allocate_scope_depth_--;
 728   DCHECK(heap_->always_allocate_scope_depth_ == 0);
 729 }
 730
 731
 732 #ifdef VERIFY_HEAP
 733 NoWeakObjectVerificationScope::NoWeakObjectVerificationScope() {
 734   Isolate* isolate = Isolate::Current();
 735   isolate->heap()->no_weak_object_verification_scope_depth_++;
 736 }
 737
 738
 739 NoWeakObjectVerificationScope::~NoWeakObjectVerificationScope() {
 740   Isolate* isolate = Isolate::Current();
 741   isolate->heap()->no_weak_object_verification_scope_depth_--;
 742 }
 743 #endif
 744
 745
 746 GCCallbacksScope::GCCallbacksScope(Heap* heap) : heap_(heap) {
 747   heap_->gc_callbacks_depth_++;
 748 }
 749
 750
 751 GCCallbacksScope::~GCCallbacksScope() { heap_->gc_callbacks_depth_--; }
 752
 753
 754 bool GCCallbacksScope::CheckReenter() {
 755   return heap_->gc_callbacks_depth_ == 1;
 756 }
 757
 758
 759 void VerifyPointersVisitor::VisitPointers(Object** start, Object** end) {
 760   for (Object** current = start; current < end; current++) {
 761     if ((*current)->IsHeapObject()) {
 762       HeapObject* object = HeapObject::cast(*current);
 763       CHECK(object->GetIsolate()->heap()->Contains(object));
 764       CHECK(object->map()->IsMap());
 765     }
 766   }
 767 }
 768
 769
 770 void VerifySmisVisitor::VisitPointers(Object** start, Object** end) {
 771   for (Object** current = start; current < end; current++) {
 772     CHECK((*current)->IsSmi());
 773   }
 774 }
 775 }
 776 }  // namespace v8::internal
 777
 778 #endif  // V8_HEAP_HEAP_INL_H_