1 // Copyright 2012 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #ifndef V8_HEAP_INL_H_ 29 #define V8_HEAP_INL_H_ 30 31 #include "heap.h" 32 #include "isolate.h" 33 #include "list-inl.h" 34 #include "objects.h" 35 #include "platform.h" 36 #include "v8-counters.h" 37 #include "store-buffer.h" 38 #include "store-buffer-inl.h" 39 40 namespace v8 { 41 namespace internal { 42 43 void PromotionQueue::insert(HeapObject* target, int size) { 44 if (emergency_stack_ != NULL) { 45 emergency_stack_->Add(Entry(target, size)); 46 return; 47 } 48 49 if (NewSpacePage::IsAtStart(reinterpret_cast<Address>(rear_))) { 50 NewSpacePage* rear_page = 51 NewSpacePage::FromAddress(reinterpret_cast<Address>(rear_)); 52 ASSERT(!rear_page->prev_page()->is_anchor()); 53 rear_ = reinterpret_cast<intptr_t*>(rear_page->prev_page()->area_end()); 54 ActivateGuardIfOnTheSamePage(); 55 } 56 57 if (guard_) { 58 ASSERT(GetHeadPage() == 59 Page::FromAllocationTop(reinterpret_cast<Address>(limit_))); 60 61 if ((rear_ - 2) < limit_) { 62 RelocateQueueHead(); 63 emergency_stack_->Add(Entry(target, size)); 64 return; 65 } 66 } 67 68 *(--rear_) = reinterpret_cast<intptr_t>(target); 69 *(--rear_) = size; 70 // Assert no overflow into live objects. 71 #ifdef DEBUG 72 SemiSpace::AssertValidRange(HEAP->new_space()->top(), 73 reinterpret_cast<Address>(rear_)); 74 #endif 75 } 76 77 78 void PromotionQueue::ActivateGuardIfOnTheSamePage() { 79 guard_ = guard_ || 80 heap_->new_space()->active_space()->current_page()->address() == 81 GetHeadPage()->address(); 82 } 83 84 85 MaybeObject* Heap::AllocateStringFromUtf8(Vector<const char> str, 86 PretenureFlag pretenure) { 87 // Check for ASCII first since this is the common case. 88 const char* start = str.start(); 89 int length = str.length(); 90 int non_ascii_start = String::NonAsciiStart(start, length); 91 if (non_ascii_start >= length) { 92 // If the string is ASCII, we do not need to convert the characters 93 // since UTF8 is backwards compatible with ASCII. 94 return AllocateStringFromOneByte(str, pretenure); 95 } 96 // Non-ASCII and we need to decode. 97 return AllocateStringFromUtf8Slow(str, non_ascii_start, pretenure); 98 } 99 100 101 template<> 102 bool inline Heap::IsOneByte(Vector<const char> str, int chars) { 103 // TODO(dcarney): incorporate Latin-1 check when Latin-1 is supported? 104 // ASCII only check. 105 return chars == str.length(); 106 } 107 108 109 template<> 110 bool inline Heap::IsOneByte(String* str, int chars) { 111 return str->IsOneByteRepresentation(); 112 } 113 114 115 MaybeObject* Heap::AllocateInternalizedStringFromUtf8( 116 Vector<const char> str, int chars, uint32_t hash_field) { 117 if (IsOneByte(str, chars)) { 118 return AllocateOneByteInternalizedString( 119 Vector<const uint8_t>::cast(str), hash_field); 120 } 121 return AllocateInternalizedStringImpl<false>(str, chars, hash_field); 122 } 123 124 125 template<typename T> 126 MaybeObject* Heap::AllocateInternalizedStringImpl( 127 T t, int chars, uint32_t hash_field) { 128 if (IsOneByte(t, chars)) { 129 return AllocateInternalizedStringImpl<true>(t, chars, hash_field); 130 } 131 return AllocateInternalizedStringImpl<false>(t, chars, hash_field); 132 } 133 134 135 MaybeObject* Heap::AllocateOneByteInternalizedString(Vector<const uint8_t> str, 136 uint32_t hash_field) { 137 if (str.length() > SeqOneByteString::kMaxLength) { 138 return Failure::OutOfMemoryException(0x2); 139 } 140 // Compute map and object size. 141 Map* map = ascii_internalized_string_map(); 142 int size = SeqOneByteString::SizeFor(str.length()); 143 144 // Allocate string. 145 Object* result; 146 { MaybeObject* maybe_result = (size > Page::kMaxNonCodeHeapObjectSize) 147 ? lo_space_->AllocateRaw(size, NOT_EXECUTABLE) 148 : old_data_space_->AllocateRaw(size); 149 if (!maybe_result->ToObject(&result)) return maybe_result; 150 } 151 152 // String maps are all immortal immovable objects. 153 reinterpret_cast<HeapObject*>(result)->set_map_no_write_barrier(map); 154 // Set length and hash fields of the allocated string. 155 String* answer = String::cast(result); 156 answer->set_length(str.length()); 157 answer->set_hash_field(hash_field); 158 159 ASSERT_EQ(size, answer->Size()); 160 161 // Fill in the characters. 162 OS::MemCopy(answer->address() + SeqOneByteString::kHeaderSize, 163 str.start(), str.length()); 164 165 return answer; 166 } 167 168 169 MaybeObject* Heap::AllocateTwoByteInternalizedString(Vector<const uc16> str, 170 uint32_t hash_field) { 171 if (str.length() > SeqTwoByteString::kMaxLength) { 172 return Failure::OutOfMemoryException(0x3); 173 } 174 // Compute map and object size. 175 Map* map = internalized_string_map(); 176 int size = SeqTwoByteString::SizeFor(str.length()); 177 178 // Allocate string. 179 Object* result; 180 { MaybeObject* maybe_result = (size > Page::kMaxNonCodeHeapObjectSize) 181 ? lo_space_->AllocateRaw(size, NOT_EXECUTABLE) 182 : old_data_space_->AllocateRaw(size); 183 if (!maybe_result->ToObject(&result)) return maybe_result; 184 } 185 186 reinterpret_cast<HeapObject*>(result)->set_map(map); 187 // Set length and hash fields of the allocated string. 188 String* answer = String::cast(result); 189 answer->set_length(str.length()); 190 answer->set_hash_field(hash_field); 191 192 ASSERT_EQ(size, answer->Size()); 193 194 // Fill in the characters. 195 OS::MemCopy(answer->address() + SeqTwoByteString::kHeaderSize, 196 str.start(), str.length() * kUC16Size); 197 198 return answer; 199 } 200 201 MaybeObject* Heap::CopyFixedArray(FixedArray* src) { 202 return CopyFixedArrayWithMap(src, src->map()); 203 } 204 205 206 MaybeObject* Heap::CopyFixedDoubleArray(FixedDoubleArray* src) { 207 return CopyFixedDoubleArrayWithMap(src, src->map()); 208 } 209 210 211 MaybeObject* Heap::AllocateRaw(int size_in_bytes, 212 AllocationSpace space, 213 AllocationSpace retry_space) { 214 ASSERT(AllowHandleAllocation::IsAllowed() && gc_state_ == NOT_IN_GC); 215 ASSERT(space != NEW_SPACE || 216 retry_space == OLD_POINTER_SPACE || 217 retry_space == OLD_DATA_SPACE || 218 retry_space == LO_SPACE); 219 #ifdef DEBUG 220 if (FLAG_gc_interval >= 0 && 221 !disallow_allocation_failure_ && 222 Heap::allocation_timeout_-- <= 0) { 223 return Failure::RetryAfterGC(space); 224 } 225 isolate_->counters()->objs_since_last_full()->Increment(); 226 isolate_->counters()->objs_since_last_young()->Increment(); 227 #endif 228 MaybeObject* result; 229 if (NEW_SPACE == space) { 230 result = new_space_.AllocateRaw(size_in_bytes); 231 if (always_allocate() && result->IsFailure()) { 232 space = retry_space; 233 } else { 234 return result; 235 } 236 } 237 238 if (OLD_POINTER_SPACE == space) { 239 result = old_pointer_space_->AllocateRaw(size_in_bytes); 240 } else if (OLD_DATA_SPACE == space) { 241 result = old_data_space_->AllocateRaw(size_in_bytes); 242 } else if (CODE_SPACE == space) { 243 result = code_space_->AllocateRaw(size_in_bytes); 244 } else if (LO_SPACE == space) { 245 result = lo_space_->AllocateRaw(size_in_bytes, NOT_EXECUTABLE); 246 } else if (CELL_SPACE == space) { 247 result = cell_space_->AllocateRaw(size_in_bytes); 248 } else if (PROPERTY_CELL_SPACE == space) { 249 result = property_cell_space_->AllocateRaw(size_in_bytes); 250 } else { 251 ASSERT(MAP_SPACE == space); 252 result = map_space_->AllocateRaw(size_in_bytes); 253 } 254 if (result->IsFailure()) old_gen_exhausted_ = true; 255 return result; 256 } 257 258 259 MaybeObject* Heap::NumberFromInt32( 260 int32_t value, PretenureFlag pretenure) { 261 if (Smi::IsValid(value)) return Smi::FromInt(value); 262 // Bypass NumberFromDouble to avoid various redundant checks. 263 return AllocateHeapNumber(FastI2D(value), pretenure); 264 } 265 266 267 MaybeObject* Heap::NumberFromUint32( 268 uint32_t value, PretenureFlag pretenure) { 269 if (static_cast<int32_t>(value) >= 0 && 270 Smi::IsValid(static_cast<int32_t>(value))) { 271 return Smi::FromInt(static_cast<int32_t>(value)); 272 } 273 // Bypass NumberFromDouble to avoid various redundant checks. 274 return AllocateHeapNumber(FastUI2D(value), pretenure); 275 } 276 277 278 void Heap::FinalizeExternalString(String* string) { 279 ASSERT(string->IsExternalString()); 280 v8::String::ExternalStringResourceBase** resource_addr = 281 reinterpret_cast<v8::String::ExternalStringResourceBase**>( 282 reinterpret_cast<byte*>(string) + 283 ExternalString::kResourceOffset - 284 kHeapObjectTag); 285 286 // Dispose of the C++ object if it has not already been disposed. 287 if (*resource_addr != NULL) { 288 (*resource_addr)->Dispose(); 289 *resource_addr = NULL; 290 } 291 } 292 293 294 MaybeObject* Heap::AllocateRawMap() { 295 #ifdef DEBUG 296 isolate_->counters()->objs_since_last_full()->Increment(); 297 isolate_->counters()->objs_since_last_young()->Increment(); 298 #endif 299 MaybeObject* result = map_space_->AllocateRaw(Map::kSize); 300 if (result->IsFailure()) old_gen_exhausted_ = true; 301 return result; 302 } 303 304 305 MaybeObject* Heap::AllocateRawCell() { 306 #ifdef DEBUG 307 isolate_->counters()->objs_since_last_full()->Increment(); 308 isolate_->counters()->objs_since_last_young()->Increment(); 309 #endif 310 MaybeObject* result = cell_space_->AllocateRaw(Cell::kSize); 311 if (result->IsFailure()) old_gen_exhausted_ = true; 312 return result; 313 } 314 315 316 MaybeObject* Heap::AllocateRawPropertyCell() { 317 #ifdef DEBUG 318 isolate_->counters()->objs_since_last_full()->Increment(); 319 isolate_->counters()->objs_since_last_young()->Increment(); 320 #endif 321 MaybeObject* result = 322 property_cell_space_->AllocateRaw(PropertyCell::kSize); 323 if (result->IsFailure()) old_gen_exhausted_ = true; 324 return result; 325 } 326 327 328 bool Heap::InNewSpace(Object* object) { 329 bool result = new_space_.Contains(object); 330 ASSERT(!result || // Either not in new space 331 gc_state_ != NOT_IN_GC || // ... or in the middle of GC 332 InToSpace(object)); // ... or in to-space (where we allocate). 333 return result; 334 } 335 336 337 bool Heap::InNewSpace(Address address) { 338 return new_space_.Contains(address); 339 } 340 341 342 bool Heap::InFromSpace(Object* object) { 343 return new_space_.FromSpaceContains(object); 344 } 345 346 347 bool Heap::InToSpace(Object* object) { 348 return new_space_.ToSpaceContains(object); 349 } 350 351 352 bool Heap::InOldPointerSpace(Address address) { 353 return old_pointer_space_->Contains(address); 354 } 355 356 357 bool Heap::InOldPointerSpace(Object* object) { 358 return InOldPointerSpace(reinterpret_cast<Address>(object)); 359 } 360 361 362 bool Heap::InOldDataSpace(Address address) { 363 return old_data_space_->Contains(address); 364 } 365 366 367 bool Heap::InOldDataSpace(Object* object) { 368 return InOldDataSpace(reinterpret_cast<Address>(object)); 369 } 370 371 372 bool Heap::OldGenerationAllocationLimitReached() { 373 if (!incremental_marking()->IsStopped()) return false; 374 return OldGenerationSpaceAvailable() < 0; 375 } 376 377 378 bool Heap::ShouldBePromoted(Address old_address, int object_size) { 379 // An object should be promoted if: 380 // - the object has survived a scavenge operation or 381 // - to space is already 25% full. 382 NewSpacePage* page = NewSpacePage::FromAddress(old_address); 383 Address age_mark = new_space_.age_mark(); 384 bool below_mark = page->IsFlagSet(MemoryChunk::NEW_SPACE_BELOW_AGE_MARK) && 385 (!page->ContainsLimit(age_mark) || old_address < age_mark); 386 return below_mark || (new_space_.Size() + object_size) >= 387 (new_space_.EffectiveCapacity() >> 2); 388 } 389 390 391 void Heap::RecordWrite(Address address, int offset) { 392 if (!InNewSpace(address)) store_buffer_.Mark(address + offset); 393 } 394 395 396 void Heap::RecordWrites(Address address, int start, int len) { 397 if (!InNewSpace(address)) { 398 for (int i = 0; i < len; i++) { 399 store_buffer_.Mark(address + start + i * kPointerSize); 400 } 401 } 402 } 403 404 405 OldSpace* Heap::TargetSpace(HeapObject* object) { 406 InstanceType type = object->map()->instance_type(); 407 AllocationSpace space = TargetSpaceId(type); 408 return (space == OLD_POINTER_SPACE) 409 ? old_pointer_space_ 410 : old_data_space_; 411 } 412 413 414 AllocationSpace Heap::TargetSpaceId(InstanceType type) { 415 // Heap numbers and sequential strings are promoted to old data space, all 416 // other object types are promoted to old pointer space. We do not use 417 // object->IsHeapNumber() and object->IsSeqString() because we already 418 // know that object has the heap object tag. 419 420 // These objects are never allocated in new space. 421 ASSERT(type != MAP_TYPE); 422 ASSERT(type != CODE_TYPE); 423 ASSERT(type != ODDBALL_TYPE); 424 ASSERT(type != CELL_TYPE); 425 ASSERT(type != PROPERTY_CELL_TYPE); 426 427 if (type <= LAST_NAME_TYPE) { 428 if (type == SYMBOL_TYPE) return OLD_POINTER_SPACE; 429 ASSERT(type < FIRST_NONSTRING_TYPE); 430 // There are four string representations: sequential strings, external 431 // strings, cons strings, and sliced strings. 432 // Only the latter two contain non-map-word pointers to heap objects. 433 return ((type & kIsIndirectStringMask) == kIsIndirectStringTag) 434 ? OLD_POINTER_SPACE 435 : OLD_DATA_SPACE; 436 } else { 437 return (type <= LAST_DATA_TYPE) ? OLD_DATA_SPACE : OLD_POINTER_SPACE; 438 } 439 } 440 441 442 bool Heap::AllowedToBeMigrated(HeapObject* object, AllocationSpace dst) { 443 // Object migration is governed by the following rules: 444 // 445 // 1) Objects in new-space can be migrated to one of the old spaces 446 // that matches their target space or they stay in new-space. 447 // 2) Objects in old-space stay in the same space when migrating. 448 // 3) Fillers (two or more words) can migrate due to left-trimming of 449 // fixed arrays in new-space, old-data-space and old-pointer-space. 450 // 4) Fillers (one word) can never migrate, they are skipped by 451 // incremental marking explicitly to prevent invalid pattern. 452 // 453 // Since this function is used for debugging only, we do not place 454 // asserts here, but check everything explicitly. 455 if (object->map() == one_pointer_filler_map()) return false; 456 InstanceType type = object->map()->instance_type(); 457 MemoryChunk* chunk = MemoryChunk::FromAddress(object->address()); 458 AllocationSpace src = chunk->owner()->identity(); 459 switch (src) { 460 case NEW_SPACE: 461 return dst == src || dst == TargetSpaceId(type); 462 case OLD_POINTER_SPACE: 463 return dst == src && (dst == TargetSpaceId(type) || object->IsFiller()); 464 case OLD_DATA_SPACE: 465 return dst == src && dst == TargetSpaceId(type); 466 case CODE_SPACE: 467 return dst == src && type == CODE_TYPE; 468 case MAP_SPACE: 469 case CELL_SPACE: 470 case PROPERTY_CELL_SPACE: 471 case LO_SPACE: 472 return false; 473 } 474 UNREACHABLE(); 475 return false; 476 } 477 478 479 void Heap::CopyBlock(Address dst, Address src, int byte_size) { 480 CopyWords(reinterpret_cast<Object**>(dst), 481 reinterpret_cast<Object**>(src), 482 static_cast<size_t>(byte_size / kPointerSize)); 483 } 484 485 486 void Heap::MoveBlock(Address dst, Address src, int byte_size) { 487 ASSERT(IsAligned(byte_size, kPointerSize)); 488 489 int size_in_words = byte_size / kPointerSize; 490 491 if ((dst < src) || (dst >= (src + byte_size))) { 492 Object** src_slot = reinterpret_cast<Object**>(src); 493 Object** dst_slot = reinterpret_cast<Object**>(dst); 494 Object** end_slot = src_slot + size_in_words; 495 496 while (src_slot != end_slot) { 497 *dst_slot++ = *src_slot++; 498 } 499 } else { 500 OS::MemMove(dst, src, static_cast<size_t>(byte_size)); 501 } 502 } 503 504 505 void Heap::ScavengePointer(HeapObject** p) { 506 ScavengeObject(p, *p); 507 } 508 509 510 void Heap::ScavengeObject(HeapObject** p, HeapObject* object) { 511 ASSERT(HEAP->InFromSpace(object)); 512 513 // We use the first word (where the map pointer usually is) of a heap 514 // object to record the forwarding pointer. A forwarding pointer can 515 // point to an old space, the code space, or the to space of the new 516 // generation. 517 MapWord first_word = object->map_word(); 518 519 // If the first word is a forwarding address, the object has already been 520 // copied. 521 if (first_word.IsForwardingAddress()) { 522 HeapObject* dest = first_word.ToForwardingAddress(); 523 ASSERT(HEAP->InFromSpace(*p)); 524 *p = dest; 525 return; 526 } 527 528 // Call the slow part of scavenge object. 529 return ScavengeObjectSlow(p, object); 530 } 531 532 533 MaybeObject* Heap::AllocateEmptyJSArrayWithAllocationSite( 534 ElementsKind elements_kind, 535 Handle<AllocationSite> allocation_site) { 536 return AllocateJSArrayAndStorageWithAllocationSite(elements_kind, 0, 0, 537 allocation_site, DONT_INITIALIZE_ARRAY_ELEMENTS); 538 } 539 540 541 bool Heap::CollectGarbage(AllocationSpace space, const char* gc_reason) { 542 const char* collector_reason = NULL; 543 GarbageCollector collector = SelectGarbageCollector(space, &collector_reason); 544 return CollectGarbage(space, collector, gc_reason, collector_reason); 545 } 546 547 548 MaybeObject* Heap::PrepareForCompare(String* str) { 549 // Always flatten small strings and force flattening of long strings 550 // after we have accumulated a certain amount we failed to flatten. 551 static const int kMaxAlwaysFlattenLength = 32; 552 static const int kFlattenLongThreshold = 16*KB; 553 554 const int length = str->length(); 555 MaybeObject* obj = str->TryFlatten(); 556 if (length <= kMaxAlwaysFlattenLength || 557 unflattened_strings_length_ >= kFlattenLongThreshold) { 558 return obj; 559 } 560 if (obj->IsFailure()) { 561 unflattened_strings_length_ += length; 562 } 563 return str; 564 } 565 566 567 intptr_t Heap::AdjustAmountOfExternalAllocatedMemory( 568 intptr_t change_in_bytes) { 569 ASSERT(HasBeenSetUp()); 570 intptr_t amount = amount_of_external_allocated_memory_ + change_in_bytes; 571 if (change_in_bytes > 0) { 572 // Avoid overflow. 573 if (amount > amount_of_external_allocated_memory_) { 574 amount_of_external_allocated_memory_ = amount; 575 } else { 576 // Give up and reset the counters in case of an overflow. 577 amount_of_external_allocated_memory_ = 0; 578 amount_of_external_allocated_memory_at_last_global_gc_ = 0; 579 } 580 intptr_t amount_since_last_global_gc = PromotedExternalMemorySize(); 581 if (amount_since_last_global_gc > external_allocation_limit_) { 582 CollectAllGarbage(kNoGCFlags, "external memory allocation limit reached"); 583 } 584 } else { 585 // Avoid underflow. 586 if (amount >= 0) { 587 amount_of_external_allocated_memory_ = amount; 588 } else { 589 // Give up and reset the counters in case of an underflow. 590 amount_of_external_allocated_memory_ = 0; 591 amount_of_external_allocated_memory_at_last_global_gc_ = 0; 592 } 593 } 594 if (FLAG_trace_external_memory) { 595 PrintPID("%8.0f ms: ", isolate()->time_millis_since_init()); 596 PrintF("Adjust amount of external memory: delta=%6" V8_PTR_PREFIX "d KB, " 597 "amount=%6" V8_PTR_PREFIX "d KB, since_gc=%6" V8_PTR_PREFIX "d KB, " 598 "isolate=0x%08" V8PRIxPTR ".\n", 599 change_in_bytes / KB, 600 amount_of_external_allocated_memory_ / KB, 601 PromotedExternalMemorySize() / KB, 602 reinterpret_cast<intptr_t>(isolate())); 603 } 604 ASSERT(amount_of_external_allocated_memory_ >= 0); 605 return amount_of_external_allocated_memory_; 606 } 607 608 609 Isolate* Heap::isolate() { 610 return reinterpret_cast<Isolate*>(reinterpret_cast<intptr_t>(this) - 611 reinterpret_cast<size_t>(reinterpret_cast<Isolate*>(4)->heap()) + 4); 612 } 613 614 615 #ifdef DEBUG 616 #define GC_GREEDY_CHECK() \ 617 if (FLAG_gc_greedy) HEAP->GarbageCollectionGreedyCheck() 618 #else 619 #define GC_GREEDY_CHECK() { } 620 #endif 621 622 // Calls the FUNCTION_CALL function and retries it up to three times 623 // to guarantee that any allocations performed during the call will 624 // succeed if there's enough memory. 625 626 // Warning: Do not use the identifiers __object__, __maybe_object__ or 627 // __scope__ in a call to this macro. 628 629 #define CALL_AND_RETRY(ISOLATE, FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY, OOM)\ 630 do { \ 631 GC_GREEDY_CHECK(); \ 632 MaybeObject* __maybe_object__ = FUNCTION_CALL; \ 633 Object* __object__ = NULL; \ 634 if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \ 635 if (__maybe_object__->IsOutOfMemory()) { \ 636 OOM; \ 637 } \ 638 if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY; \ 639 ISOLATE->heap()->CollectGarbage(Failure::cast(__maybe_object__)-> \ 640 allocation_space(), \ 641 "allocation failure"); \ 642 __maybe_object__ = FUNCTION_CALL; \ 643 if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \ 644 if (__maybe_object__->IsOutOfMemory()) { \ 645 OOM; \ 646 } \ 647 if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY; \ 648 ISOLATE->counters()->gc_last_resort_from_handles()->Increment(); \ 649 ISOLATE->heap()->CollectAllAvailableGarbage("last resort gc"); \ 650 { \ 651 AlwaysAllocateScope __scope__; \ 652 __maybe_object__ = FUNCTION_CALL; \ 653 } \ 654 if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \ 655 if (__maybe_object__->IsOutOfMemory()) { \ 656 OOM; \ 657 } \ 658 if (__maybe_object__->IsRetryAfterGC()) { \ 659 /* TODO(1181417): Fix this. */ \ 660 v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_LAST", true); \ 661 } \ 662 RETURN_EMPTY; \ 663 } while (false) 664 665 #define CALL_AND_RETRY_OR_DIE( \ 666 ISOLATE, FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY) \ 667 CALL_AND_RETRY( \ 668 ISOLATE, \ 669 FUNCTION_CALL, \ 670 RETURN_VALUE, \ 671 RETURN_EMPTY, \ 672 v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY", true)) 673 674 #define CALL_HEAP_FUNCTION(ISOLATE, FUNCTION_CALL, TYPE) \ 675 CALL_AND_RETRY_OR_DIE(ISOLATE, \ 676 FUNCTION_CALL, \ 677 return Handle<TYPE>(TYPE::cast(__object__), ISOLATE), \ 678 return Handle<TYPE>()) \ 679 680 681 #define CALL_HEAP_FUNCTION_VOID(ISOLATE, FUNCTION_CALL) \ 682 CALL_AND_RETRY_OR_DIE(ISOLATE, FUNCTION_CALL, return, return) 683 684 685 #define CALL_HEAP_FUNCTION_PASS_EXCEPTION(ISOLATE, FUNCTION_CALL) \ 686 CALL_AND_RETRY(ISOLATE, \ 687 FUNCTION_CALL, \ 688 return __object__, \ 689 return __maybe_object__, \ 690 return __maybe_object__) 691 692 693 void ExternalStringTable::AddString(String* string) { 694 ASSERT(string->IsExternalString()); 695 if (heap_->InNewSpace(string)) { 696 new_space_strings_.Add(string); 697 } else { 698 old_space_strings_.Add(string); 699 } 700 } 701 702 703 void ExternalStringTable::Iterate(ObjectVisitor* v) { 704 if (!new_space_strings_.is_empty()) { 705 Object** start = &new_space_strings_[0]; 706 v->VisitPointers(start, start + new_space_strings_.length()); 707 } 708 if (!old_space_strings_.is_empty()) { 709 Object** start = &old_space_strings_[0]; 710 v->VisitPointers(start, start + old_space_strings_.length()); 711 } 712 } 713 714 715 // Verify() is inline to avoid ifdef-s around its calls in release 716 // mode. 717 void ExternalStringTable::Verify() { 718 #ifdef DEBUG 719 for (int i = 0; i < new_space_strings_.length(); ++i) { 720 Object* obj = Object::cast(new_space_strings_[i]); 721 // TODO(yangguo): check that the object is indeed an external string. 722 ASSERT(heap_->InNewSpace(obj)); 723 ASSERT(obj != HEAP->the_hole_value()); 724 } 725 for (int i = 0; i < old_space_strings_.length(); ++i) { 726 Object* obj = Object::cast(old_space_strings_[i]); 727 // TODO(yangguo): check that the object is indeed an external string. 728 ASSERT(!heap_->InNewSpace(obj)); 729 ASSERT(obj != HEAP->the_hole_value()); 730 } 731 #endif 732 } 733 734 735 void ExternalStringTable::AddOldString(String* string) { 736 ASSERT(string->IsExternalString()); 737 ASSERT(!heap_->InNewSpace(string)); 738 old_space_strings_.Add(string); 739 } 740 741 742 void ExternalStringTable::ShrinkNewStrings(int position) { 743 new_space_strings_.Rewind(position); 744 #ifdef VERIFY_HEAP 745 if (FLAG_verify_heap) { 746 Verify(); 747 } 748 #endif 749 } 750 751 752 void Heap::ClearInstanceofCache() { 753 set_instanceof_cache_function(the_hole_value()); 754 } 755 756 757 Object* Heap::ToBoolean(bool condition) { 758 return condition ? true_value() : false_value(); 759 } 760 761 762 void Heap::CompletelyClearInstanceofCache() { 763 set_instanceof_cache_map(the_hole_value()); 764 set_instanceof_cache_function(the_hole_value()); 765 } 766 767 768 MaybeObject* TranscendentalCache::Get(Type type, double input) { 769 SubCache* cache = caches_[type]; 770 if (cache == NULL) { 771 caches_[type] = cache = new SubCache(type); 772 } 773 return cache->Get(input); 774 } 775 776 777 Address TranscendentalCache::cache_array_address() { 778 return reinterpret_cast<Address>(caches_); 779 } 780 781 782 double TranscendentalCache::SubCache::Calculate(double input) { 783 switch (type_) { 784 case ACOS: 785 return acos(input); 786 case ASIN: 787 return asin(input); 788 case ATAN: 789 return atan(input); 790 case COS: 791 return fast_cos(input); 792 case EXP: 793 return exp(input); 794 case LOG: 795 return fast_log(input); 796 case SIN: 797 return fast_sin(input); 798 case TAN: 799 return fast_tan(input); 800 default: 801 return 0.0; // Never happens. 802 } 803 } 804 805 806 MaybeObject* TranscendentalCache::SubCache::Get(double input) { 807 Converter c; 808 c.dbl = input; 809 int hash = Hash(c); 810 Element e = elements_[hash]; 811 if (e.in[0] == c.integers[0] && 812 e.in[1] == c.integers[1]) { 813 ASSERT(e.output != NULL); 814 isolate_->counters()->transcendental_cache_hit()->Increment(); 815 return e.output; 816 } 817 double answer = Calculate(input); 818 isolate_->counters()->transcendental_cache_miss()->Increment(); 819 Object* heap_number; 820 { MaybeObject* maybe_heap_number = 821 isolate_->heap()->AllocateHeapNumber(answer); 822 if (!maybe_heap_number->ToObject(&heap_number)) return maybe_heap_number; 823 } 824 elements_[hash].in[0] = c.integers[0]; 825 elements_[hash].in[1] = c.integers[1]; 826 elements_[hash].output = heap_number; 827 return heap_number; 828 } 829 830 831 AlwaysAllocateScope::AlwaysAllocateScope() { 832 // We shouldn't hit any nested scopes, because that requires 833 // non-handle code to call handle code. The code still works but 834 // performance will degrade, so we want to catch this situation 835 // in debug mode. 836 ASSERT(HEAP->always_allocate_scope_depth_ == 0); 837 HEAP->always_allocate_scope_depth_++; 838 } 839 840 841 AlwaysAllocateScope::~AlwaysAllocateScope() { 842 HEAP->always_allocate_scope_depth_--; 843 ASSERT(HEAP->always_allocate_scope_depth_ == 0); 844 } 845 846 847 #ifdef VERIFY_HEAP 848 NoWeakEmbeddedMapsVerificationScope::NoWeakEmbeddedMapsVerificationScope() { 849 HEAP->no_weak_embedded_maps_verification_scope_depth_++; 850 } 851 852 853 NoWeakEmbeddedMapsVerificationScope::~NoWeakEmbeddedMapsVerificationScope() { 854 HEAP->no_weak_embedded_maps_verification_scope_depth_--; 855 } 856 #endif 857 858 859 void VerifyPointersVisitor::VisitPointers(Object** start, Object** end) { 860 for (Object** current = start; current < end; current++) { 861 if ((*current)->IsHeapObject()) { 862 HeapObject* object = HeapObject::cast(*current); 863 CHECK(HEAP->Contains(object)); 864 CHECK(object->map()->IsMap()); 865 } 866 } 867 } 868 869 870 double GCTracer::SizeOfHeapObjects() { 871 return (static_cast<double>(HEAP->SizeOfObjects())) / MB; 872 } 873 874 875 DisallowAllocationFailure::DisallowAllocationFailure() { 876 #ifdef DEBUG 877 old_state_ = HEAP->disallow_allocation_failure_; 878 HEAP->disallow_allocation_failure_ = true; 879 #endif 880 } 881 882 883 DisallowAllocationFailure::~DisallowAllocationFailure() { 884 #ifdef DEBUG 885 HEAP->disallow_allocation_failure_ = old_state_; 886 #endif 887 } 888 889 890 } } // namespace v8::internal 891 892 #endif // V8_HEAP_INL_H_ 893