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 #include "src/v8.h" 6 7 #include "src/accessors.h" 8 #include "src/api.h" 9 #include "src/base/platform/platform.h" 10 #include "src/bootstrapper.h" 11 #include "src/code-stubs.h" 12 #include "src/deoptimizer.h" 13 #include "src/execution.h" 14 #include "src/global-handles.h" 15 #include "src/ic/ic.h" 16 #include "src/ic/stub-cache.h" 17 #include "src/natives.h" 18 #include "src/objects.h" 19 #include "src/runtime.h" 20 #include "src/serialize.h" 21 #include "src/snapshot.h" 22 #include "src/snapshot-source-sink.h" 23 #include "src/v8threads.h" 24 #include "src/version.h" 25 26 namespace v8 { 27 namespace internal { 28 29 30 // ----------------------------------------------------------------------------- 31 // Coding of external references. 32 33 // The encoding of an external reference. The type is in the high word. 34 // The id is in the low word. 35 static uint32_t EncodeExternal(TypeCode type, uint16_t id) { 36 return static_cast<uint32_t>(type) << 16 | id; 37 } 38 39 40 static int* GetInternalPointer(StatsCounter* counter) { 41 // All counters refer to dummy_counter, if deserializing happens without 42 // setting up counters. 43 static int dummy_counter = 0; 44 return counter->Enabled() ? counter->GetInternalPointer() : &dummy_counter; 45 } 46 47 48 ExternalReferenceTable* ExternalReferenceTable::instance(Isolate* isolate) { 49 ExternalReferenceTable* external_reference_table = 50 isolate->external_reference_table(); 51 if (external_reference_table == NULL) { 52 external_reference_table = new ExternalReferenceTable(isolate); 53 isolate->set_external_reference_table(external_reference_table); 54 } 55 return external_reference_table; 56 } 57 58 59 void ExternalReferenceTable::AddFromId(TypeCode type, 60 uint16_t id, 61 const char* name, 62 Isolate* isolate) { 63 Address address; 64 switch (type) { 65 case C_BUILTIN: { 66 ExternalReference ref(static_cast<Builtins::CFunctionId>(id), isolate); 67 address = ref.address(); 68 break; 69 } 70 case BUILTIN: { 71 ExternalReference ref(static_cast<Builtins::Name>(id), isolate); 72 address = ref.address(); 73 break; 74 } 75 case RUNTIME_FUNCTION: { 76 ExternalReference ref(static_cast<Runtime::FunctionId>(id), isolate); 77 address = ref.address(); 78 break; 79 } 80 case IC_UTILITY: { 81 ExternalReference ref(IC_Utility(static_cast<IC::UtilityId>(id)), 82 isolate); 83 address = ref.address(); 84 break; 85 } 86 default: 87 UNREACHABLE(); 88 return; 89 } 90 Add(address, type, id, name); 91 } 92 93 94 void ExternalReferenceTable::Add(Address address, 95 TypeCode type, 96 uint16_t id, 97 const char* name) { 98 DCHECK_NE(NULL, address); 99 ExternalReferenceEntry entry; 100 entry.address = address; 101 entry.code = EncodeExternal(type, id); 102 entry.name = name; 103 DCHECK_NE(0, entry.code); 104 // Assert that the code is added in ascending order to rule out duplicates. 105 DCHECK((size() == 0) || (code(size() - 1) < entry.code)); 106 refs_.Add(entry); 107 if (id > max_id_[type]) max_id_[type] = id; 108 } 109 110 111 void ExternalReferenceTable::PopulateTable(Isolate* isolate) { 112 for (int type_code = 0; type_code < kTypeCodeCount; type_code++) { 113 max_id_[type_code] = 0; 114 } 115 116 // Miscellaneous 117 Add(ExternalReference::roots_array_start(isolate).address(), 118 "Heap::roots_array_start()"); 119 Add(ExternalReference::address_of_stack_limit(isolate).address(), 120 "StackGuard::address_of_jslimit()"); 121 Add(ExternalReference::address_of_real_stack_limit(isolate).address(), 122 "StackGuard::address_of_real_jslimit()"); 123 Add(ExternalReference::new_space_start(isolate).address(), 124 "Heap::NewSpaceStart()"); 125 Add(ExternalReference::new_space_mask(isolate).address(), 126 "Heap::NewSpaceMask()"); 127 Add(ExternalReference::new_space_allocation_limit_address(isolate).address(), 128 "Heap::NewSpaceAllocationLimitAddress()"); 129 Add(ExternalReference::new_space_allocation_top_address(isolate).address(), 130 "Heap::NewSpaceAllocationTopAddress()"); 131 Add(ExternalReference::debug_break(isolate).address(), "Debug::Break()"); 132 Add(ExternalReference::debug_step_in_fp_address(isolate).address(), 133 "Debug::step_in_fp_addr()"); 134 Add(ExternalReference::mod_two_doubles_operation(isolate).address(), 135 "mod_two_doubles"); 136 // Keyed lookup cache. 137 Add(ExternalReference::keyed_lookup_cache_keys(isolate).address(), 138 "KeyedLookupCache::keys()"); 139 Add(ExternalReference::keyed_lookup_cache_field_offsets(isolate).address(), 140 "KeyedLookupCache::field_offsets()"); 141 Add(ExternalReference::handle_scope_next_address(isolate).address(), 142 "HandleScope::next"); 143 Add(ExternalReference::handle_scope_limit_address(isolate).address(), 144 "HandleScope::limit"); 145 Add(ExternalReference::handle_scope_level_address(isolate).address(), 146 "HandleScope::level"); 147 Add(ExternalReference::new_deoptimizer_function(isolate).address(), 148 "Deoptimizer::New()"); 149 Add(ExternalReference::compute_output_frames_function(isolate).address(), 150 "Deoptimizer::ComputeOutputFrames()"); 151 Add(ExternalReference::address_of_min_int().address(), 152 "LDoubleConstant::min_int"); 153 Add(ExternalReference::address_of_one_half().address(), 154 "LDoubleConstant::one_half"); 155 Add(ExternalReference::isolate_address(isolate).address(), "isolate"); 156 Add(ExternalReference::address_of_negative_infinity().address(), 157 "LDoubleConstant::negative_infinity"); 158 Add(ExternalReference::power_double_double_function(isolate).address(), 159 "power_double_double_function"); 160 Add(ExternalReference::power_double_int_function(isolate).address(), 161 "power_double_int_function"); 162 Add(ExternalReference::math_log_double_function(isolate).address(), 163 "std::log"); 164 Add(ExternalReference::store_buffer_top(isolate).address(), 165 "store_buffer_top"); 166 Add(ExternalReference::address_of_canonical_non_hole_nan().address(), 167 "canonical_nan"); 168 Add(ExternalReference::address_of_the_hole_nan().address(), "the_hole_nan"); 169 Add(ExternalReference::get_date_field_function(isolate).address(), 170 "JSDate::GetField"); 171 Add(ExternalReference::date_cache_stamp(isolate).address(), 172 "date_cache_stamp"); 173 Add(ExternalReference::address_of_pending_message_obj(isolate).address(), 174 "address_of_pending_message_obj"); 175 Add(ExternalReference::address_of_has_pending_message(isolate).address(), 176 "address_of_has_pending_message"); 177 Add(ExternalReference::address_of_pending_message_script(isolate).address(), 178 "pending_message_script"); 179 Add(ExternalReference::get_make_code_young_function(isolate).address(), 180 "Code::MakeCodeYoung"); 181 Add(ExternalReference::cpu_features().address(), "cpu_features"); 182 Add(ExternalReference(Runtime::kAllocateInNewSpace, isolate).address(), 183 "Runtime::AllocateInNewSpace"); 184 Add(ExternalReference(Runtime::kAllocateInTargetSpace, isolate).address(), 185 "Runtime::AllocateInTargetSpace"); 186 Add(ExternalReference::old_pointer_space_allocation_top_address(isolate) 187 .address(), 188 "Heap::OldPointerSpaceAllocationTopAddress"); 189 Add(ExternalReference::old_pointer_space_allocation_limit_address(isolate) 190 .address(), 191 "Heap::OldPointerSpaceAllocationLimitAddress"); 192 Add(ExternalReference::old_data_space_allocation_top_address(isolate) 193 .address(), 194 "Heap::OldDataSpaceAllocationTopAddress"); 195 Add(ExternalReference::old_data_space_allocation_limit_address(isolate) 196 .address(), 197 "Heap::OldDataSpaceAllocationLimitAddress"); 198 Add(ExternalReference::allocation_sites_list_address(isolate).address(), 199 "Heap::allocation_sites_list_address()"); 200 Add(ExternalReference::address_of_uint32_bias().address(), "uint32_bias"); 201 Add(ExternalReference::get_mark_code_as_executed_function(isolate).address(), 202 "Code::MarkCodeAsExecuted"); 203 Add(ExternalReference::is_profiling_address(isolate).address(), 204 "CpuProfiler::is_profiling"); 205 Add(ExternalReference::scheduled_exception_address(isolate).address(), 206 "Isolate::scheduled_exception"); 207 Add(ExternalReference::invoke_function_callback(isolate).address(), 208 "InvokeFunctionCallback"); 209 Add(ExternalReference::invoke_accessor_getter_callback(isolate).address(), 210 "InvokeAccessorGetterCallback"); 211 Add(ExternalReference::flush_icache_function(isolate).address(), 212 "CpuFeatures::FlushICache"); 213 Add(ExternalReference::log_enter_external_function(isolate).address(), 214 "Logger::EnterExternal"); 215 Add(ExternalReference::log_leave_external_function(isolate).address(), 216 "Logger::LeaveExternal"); 217 Add(ExternalReference::address_of_minus_one_half().address(), 218 "double_constants.minus_one_half"); 219 Add(ExternalReference::stress_deopt_count(isolate).address(), 220 "Isolate::stress_deopt_count_address()"); 221 Add(ExternalReference::incremental_marking_record_write_function(isolate) 222 .address(), 223 "IncrementalMarking::RecordWriteFromCode"); 224 225 // Debug addresses 226 Add(ExternalReference::debug_after_break_target_address(isolate).address(), 227 "Debug::after_break_target_address()"); 228 Add(ExternalReference::debug_restarter_frame_function_pointer_address(isolate) 229 .address(), 230 "Debug::restarter_frame_function_pointer_address()"); 231 Add(ExternalReference::debug_is_active_address(isolate).address(), 232 "Debug::is_active_address()"); 233 234 #ifndef V8_INTERPRETED_REGEXP 235 Add(ExternalReference::re_case_insensitive_compare_uc16(isolate).address(), 236 "NativeRegExpMacroAssembler::CaseInsensitiveCompareUC16()"); 237 Add(ExternalReference::re_check_stack_guard_state(isolate).address(), 238 "RegExpMacroAssembler*::CheckStackGuardState()"); 239 Add(ExternalReference::re_grow_stack(isolate).address(), 240 "NativeRegExpMacroAssembler::GrowStack()"); 241 Add(ExternalReference::re_word_character_map().address(), 242 "NativeRegExpMacroAssembler::word_character_map"); 243 Add(ExternalReference::address_of_regexp_stack_limit(isolate).address(), 244 "RegExpStack::limit_address()"); 245 Add(ExternalReference::address_of_regexp_stack_memory_address(isolate) 246 .address(), 247 "RegExpStack::memory_address()"); 248 Add(ExternalReference::address_of_regexp_stack_memory_size(isolate).address(), 249 "RegExpStack::memory_size()"); 250 Add(ExternalReference::address_of_static_offsets_vector(isolate).address(), 251 "OffsetsVector::static_offsets_vector"); 252 #endif // V8_INTERPRETED_REGEXP 253 254 // The following populates all of the different type of external references 255 // into the ExternalReferenceTable. 256 // 257 // NOTE: This function was originally 100k of code. It has since been 258 // rewritten to be mostly table driven, as the callback macro style tends to 259 // very easily cause code bloat. Please be careful in the future when adding 260 // new references. 261 262 struct RefTableEntry { 263 TypeCode type; 264 uint16_t id; 265 const char* name; 266 }; 267 268 static const RefTableEntry ref_table[] = { 269 // Builtins 270 #define DEF_ENTRY_C(name, ignored) \ 271 { C_BUILTIN, \ 272 Builtins::c_##name, \ 273 "Builtins::" #name }, 274 275 BUILTIN_LIST_C(DEF_ENTRY_C) 276 #undef DEF_ENTRY_C 277 278 #define DEF_ENTRY_C(name, ignored) \ 279 { BUILTIN, \ 280 Builtins::k##name, \ 281 "Builtins::" #name }, 282 #define DEF_ENTRY_A(name, kind, state, extra) DEF_ENTRY_C(name, ignored) 283 284 BUILTIN_LIST_C(DEF_ENTRY_C) 285 BUILTIN_LIST_A(DEF_ENTRY_A) 286 BUILTIN_LIST_DEBUG_A(DEF_ENTRY_A) 287 #undef DEF_ENTRY_C 288 #undef DEF_ENTRY_A 289 290 // Runtime functions 291 #define RUNTIME_ENTRY(name, nargs, ressize) \ 292 { RUNTIME_FUNCTION, \ 293 Runtime::k##name, \ 294 "Runtime::" #name }, 295 296 RUNTIME_FUNCTION_LIST(RUNTIME_ENTRY) 297 INLINE_OPTIMIZED_FUNCTION_LIST(RUNTIME_ENTRY) 298 #undef RUNTIME_ENTRY 299 300 #define INLINE_OPTIMIZED_ENTRY(name, nargs, ressize) \ 301 { RUNTIME_FUNCTION, \ 302 Runtime::kInlineOptimized##name, \ 303 "Runtime::" #name }, 304 305 INLINE_OPTIMIZED_FUNCTION_LIST(INLINE_OPTIMIZED_ENTRY) 306 #undef INLINE_OPTIMIZED_ENTRY 307 308 // IC utilities 309 #define IC_ENTRY(name) \ 310 { IC_UTILITY, \ 311 IC::k##name, \ 312 "IC::" #name }, 313 314 IC_UTIL_LIST(IC_ENTRY) 315 #undef IC_ENTRY 316 }; // end of ref_table[]. 317 318 for (size_t i = 0; i < arraysize(ref_table); ++i) { 319 AddFromId(ref_table[i].type, 320 ref_table[i].id, 321 ref_table[i].name, 322 isolate); 323 } 324 325 // Stat counters 326 struct StatsRefTableEntry { 327 StatsCounter* (Counters::*counter)(); 328 uint16_t id; 329 const char* name; 330 }; 331 332 const StatsRefTableEntry stats_ref_table[] = { 333 #define COUNTER_ENTRY(name, caption) \ 334 { &Counters::name, \ 335 Counters::k_##name, \ 336 "Counters::" #name }, 337 338 STATS_COUNTER_LIST_1(COUNTER_ENTRY) 339 STATS_COUNTER_LIST_2(COUNTER_ENTRY) 340 #undef COUNTER_ENTRY 341 }; // end of stats_ref_table[]. 342 343 Counters* counters = isolate->counters(); 344 for (size_t i = 0; i < arraysize(stats_ref_table); ++i) { 345 Add(reinterpret_cast<Address>(GetInternalPointer( 346 (counters->*(stats_ref_table[i].counter))())), 347 STATS_COUNTER, 348 stats_ref_table[i].id, 349 stats_ref_table[i].name); 350 } 351 352 // Top addresses 353 354 const char* AddressNames[] = { 355 #define BUILD_NAME_LITERAL(CamelName, hacker_name) \ 356 "Isolate::" #hacker_name "_address", 357 FOR_EACH_ISOLATE_ADDRESS_NAME(BUILD_NAME_LITERAL) 358 NULL 359 #undef BUILD_NAME_LITERAL 360 }; 361 362 for (uint16_t i = 0; i < Isolate::kIsolateAddressCount; ++i) { 363 Add(isolate->get_address_from_id((Isolate::AddressId)i), 364 TOP_ADDRESS, i, AddressNames[i]); 365 } 366 367 // Accessors 368 #define ACCESSOR_INFO_DECLARATION(name) \ 369 Add(FUNCTION_ADDR(&Accessors::name##Getter), \ 370 ACCESSOR, \ 371 Accessors::k##name##Getter, \ 372 "Accessors::" #name "Getter"); \ 373 Add(FUNCTION_ADDR(&Accessors::name##Setter), \ 374 ACCESSOR, \ 375 Accessors::k##name##Setter, \ 376 "Accessors::" #name "Setter"); 377 ACCESSOR_INFO_LIST(ACCESSOR_INFO_DECLARATION) 378 #undef ACCESSOR_INFO_DECLARATION 379 380 StubCache* stub_cache = isolate->stub_cache(); 381 382 // Stub cache tables 383 Add(stub_cache->key_reference(StubCache::kPrimary).address(), 384 STUB_CACHE_TABLE, 1, "StubCache::primary_->key"); 385 Add(stub_cache->value_reference(StubCache::kPrimary).address(), 386 STUB_CACHE_TABLE, 2, "StubCache::primary_->value"); 387 Add(stub_cache->map_reference(StubCache::kPrimary).address(), 388 STUB_CACHE_TABLE, 3, "StubCache::primary_->map"); 389 Add(stub_cache->key_reference(StubCache::kSecondary).address(), 390 STUB_CACHE_TABLE, 4, "StubCache::secondary_->key"); 391 Add(stub_cache->value_reference(StubCache::kSecondary).address(), 392 STUB_CACHE_TABLE, 5, "StubCache::secondary_->value"); 393 Add(stub_cache->map_reference(StubCache::kSecondary).address(), 394 STUB_CACHE_TABLE, 6, "StubCache::secondary_->map"); 395 396 // Runtime entries 397 Add(ExternalReference::delete_handle_scope_extensions(isolate).address(), 398 RUNTIME_ENTRY, 1, "HandleScope::DeleteExtensions"); 399 Add(ExternalReference::incremental_marking_record_write_function(isolate) 400 .address(), 401 RUNTIME_ENTRY, 2, "IncrementalMarking::RecordWrite"); 402 Add(ExternalReference::store_buffer_overflow_function(isolate).address(), 403 RUNTIME_ENTRY, 3, "StoreBuffer::StoreBufferOverflow"); 404 405 // Add a small set of deopt entry addresses to encoder without generating the 406 // deopt table code, which isn't possible at deserialization time. 407 HandleScope scope(isolate); 408 for (int entry = 0; entry < kDeoptTableSerializeEntryCount; ++entry) { 409 Address address = Deoptimizer::GetDeoptimizationEntry( 410 isolate, 411 entry, 412 Deoptimizer::LAZY, 413 Deoptimizer::CALCULATE_ENTRY_ADDRESS); 414 Add(address, LAZY_DEOPTIMIZATION, entry, "lazy_deopt"); 415 } 416 } 417 418 419 ExternalReferenceEncoder::ExternalReferenceEncoder(Isolate* isolate) 420 : encodings_(HashMap::PointersMatch), 421 isolate_(isolate) { 422 ExternalReferenceTable* external_references = 423 ExternalReferenceTable::instance(isolate_); 424 for (int i = 0; i < external_references->size(); ++i) { 425 Put(external_references->address(i), i); 426 } 427 } 428 429 430 uint32_t ExternalReferenceEncoder::Encode(Address key) const { 431 int index = IndexOf(key); 432 DCHECK(key == NULL || index >= 0); 433 return index >= 0 ? 434 ExternalReferenceTable::instance(isolate_)->code(index) : 0; 435 } 436 437 438 const char* ExternalReferenceEncoder::NameOfAddress(Address key) const { 439 int index = IndexOf(key); 440 return index >= 0 ? ExternalReferenceTable::instance(isolate_)->name(index) 441 : "<unknown>"; 442 } 443 444 445 int ExternalReferenceEncoder::IndexOf(Address key) const { 446 if (key == NULL) return -1; 447 HashMap::Entry* entry = 448 const_cast<HashMap&>(encodings_).Lookup(key, Hash(key), false); 449 return entry == NULL 450 ? -1 451 : static_cast<int>(reinterpret_cast<intptr_t>(entry->value)); 452 } 453 454 455 void ExternalReferenceEncoder::Put(Address key, int index) { 456 HashMap::Entry* entry = encodings_.Lookup(key, Hash(key), true); 457 entry->value = reinterpret_cast<void*>(index); 458 } 459 460 461 ExternalReferenceDecoder::ExternalReferenceDecoder(Isolate* isolate) 462 : encodings_(NewArray<Address*>(kTypeCodeCount)), 463 isolate_(isolate) { 464 ExternalReferenceTable* external_references = 465 ExternalReferenceTable::instance(isolate_); 466 for (int type = kFirstTypeCode; type < kTypeCodeCount; ++type) { 467 int max = external_references->max_id(type) + 1; 468 encodings_[type] = NewArray<Address>(max + 1); 469 } 470 for (int i = 0; i < external_references->size(); ++i) { 471 Put(external_references->code(i), external_references->address(i)); 472 } 473 } 474 475 476 ExternalReferenceDecoder::~ExternalReferenceDecoder() { 477 for (int type = kFirstTypeCode; type < kTypeCodeCount; ++type) { 478 DeleteArray(encodings_[type]); 479 } 480 DeleteArray(encodings_); 481 } 482 483 484 class CodeAddressMap: public CodeEventLogger { 485 public: 486 explicit CodeAddressMap(Isolate* isolate) 487 : isolate_(isolate) { 488 isolate->logger()->addCodeEventListener(this); 489 } 490 491 virtual ~CodeAddressMap() { 492 isolate_->logger()->removeCodeEventListener(this); 493 } 494 495 virtual void CodeMoveEvent(Address from, Address to) { 496 address_to_name_map_.Move(from, to); 497 } 498 499 virtual void CodeDisableOptEvent(Code* code, SharedFunctionInfo* shared) { 500 } 501 502 virtual void CodeDeleteEvent(Address from) { 503 address_to_name_map_.Remove(from); 504 } 505 506 const char* Lookup(Address address) { 507 return address_to_name_map_.Lookup(address); 508 } 509 510 private: 511 class NameMap { 512 public: 513 NameMap() : impl_(HashMap::PointersMatch) {} 514 515 ~NameMap() { 516 for (HashMap::Entry* p = impl_.Start(); p != NULL; p = impl_.Next(p)) { 517 DeleteArray(static_cast<const char*>(p->value)); 518 } 519 } 520 521 void Insert(Address code_address, const char* name, int name_size) { 522 HashMap::Entry* entry = FindOrCreateEntry(code_address); 523 if (entry->value == NULL) { 524 entry->value = CopyName(name, name_size); 525 } 526 } 527 528 const char* Lookup(Address code_address) { 529 HashMap::Entry* entry = FindEntry(code_address); 530 return (entry != NULL) ? static_cast<const char*>(entry->value) : NULL; 531 } 532 533 void Remove(Address code_address) { 534 HashMap::Entry* entry = FindEntry(code_address); 535 if (entry != NULL) { 536 DeleteArray(static_cast<char*>(entry->value)); 537 RemoveEntry(entry); 538 } 539 } 540 541 void Move(Address from, Address to) { 542 if (from == to) return; 543 HashMap::Entry* from_entry = FindEntry(from); 544 DCHECK(from_entry != NULL); 545 void* value = from_entry->value; 546 RemoveEntry(from_entry); 547 HashMap::Entry* to_entry = FindOrCreateEntry(to); 548 DCHECK(to_entry->value == NULL); 549 to_entry->value = value; 550 } 551 552 private: 553 static char* CopyName(const char* name, int name_size) { 554 char* result = NewArray<char>(name_size + 1); 555 for (int i = 0; i < name_size; ++i) { 556 char c = name[i]; 557 if (c == '\0') c = ' '; 558 result[i] = c; 559 } 560 result[name_size] = '\0'; 561 return result; 562 } 563 564 HashMap::Entry* FindOrCreateEntry(Address code_address) { 565 return impl_.Lookup(code_address, ComputePointerHash(code_address), true); 566 } 567 568 HashMap::Entry* FindEntry(Address code_address) { 569 return impl_.Lookup(code_address, 570 ComputePointerHash(code_address), 571 false); 572 } 573 574 void RemoveEntry(HashMap::Entry* entry) { 575 impl_.Remove(entry->key, entry->hash); 576 } 577 578 HashMap impl_; 579 580 DISALLOW_COPY_AND_ASSIGN(NameMap); 581 }; 582 583 virtual void LogRecordedBuffer(Code* code, 584 SharedFunctionInfo*, 585 const char* name, 586 int length) { 587 address_to_name_map_.Insert(code->address(), name, length); 588 } 589 590 NameMap address_to_name_map_; 591 Isolate* isolate_; 592 }; 593 594 595 Deserializer::Deserializer(SnapshotByteSource* source) 596 : isolate_(NULL), 597 attached_objects_(NULL), 598 source_(source), 599 external_reference_decoder_(NULL) { 600 for (int i = 0; i < LAST_SPACE + 1; i++) { 601 reservations_[i] = kUninitializedReservation; 602 } 603 } 604 605 606 void Deserializer::FlushICacheForNewCodeObjects() { 607 PageIterator it(isolate_->heap()->code_space()); 608 while (it.has_next()) { 609 Page* p = it.next(); 610 CpuFeatures::FlushICache(p->area_start(), p->area_end() - p->area_start()); 611 } 612 } 613 614 615 void Deserializer::Deserialize(Isolate* isolate) { 616 isolate_ = isolate; 617 DCHECK(isolate_ != NULL); 618 isolate_->heap()->ReserveSpace(reservations_, &high_water_[0]); 619 // No active threads. 620 DCHECK_EQ(NULL, isolate_->thread_manager()->FirstThreadStateInUse()); 621 // No active handles. 622 DCHECK(isolate_->handle_scope_implementer()->blocks()->is_empty()); 623 DCHECK_EQ(NULL, external_reference_decoder_); 624 external_reference_decoder_ = new ExternalReferenceDecoder(isolate); 625 isolate_->heap()->IterateSmiRoots(this); 626 isolate_->heap()->IterateStrongRoots(this, VISIT_ONLY_STRONG); 627 isolate_->heap()->RepairFreeListsAfterBoot(); 628 isolate_->heap()->IterateWeakRoots(this, VISIT_ALL); 629 630 isolate_->heap()->set_native_contexts_list( 631 isolate_->heap()->undefined_value()); 632 isolate_->heap()->set_array_buffers_list( 633 isolate_->heap()->undefined_value()); 634 635 // The allocation site list is build during root iteration, but if no sites 636 // were encountered then it needs to be initialized to undefined. 637 if (isolate_->heap()->allocation_sites_list() == Smi::FromInt(0)) { 638 isolate_->heap()->set_allocation_sites_list( 639 isolate_->heap()->undefined_value()); 640 } 641 642 isolate_->heap()->InitializeWeakObjectToCodeTable(); 643 644 // Update data pointers to the external strings containing natives sources. 645 for (int i = 0; i < Natives::GetBuiltinsCount(); i++) { 646 Object* source = isolate_->heap()->natives_source_cache()->get(i); 647 if (!source->IsUndefined()) { 648 ExternalOneByteString::cast(source)->update_data_cache(); 649 } 650 } 651 652 FlushICacheForNewCodeObjects(); 653 654 // Issue code events for newly deserialized code objects. 655 LOG_CODE_EVENT(isolate_, LogCodeObjects()); 656 LOG_CODE_EVENT(isolate_, LogCompiledFunctions()); 657 } 658 659 660 void Deserializer::DeserializePartial(Isolate* isolate, Object** root) { 661 isolate_ = isolate; 662 for (int i = NEW_SPACE; i < kNumberOfSpaces; i++) { 663 DCHECK(reservations_[i] != kUninitializedReservation); 664 } 665 isolate_->heap()->ReserveSpace(reservations_, &high_water_[0]); 666 if (external_reference_decoder_ == NULL) { 667 external_reference_decoder_ = new ExternalReferenceDecoder(isolate); 668 } 669 670 DisallowHeapAllocation no_gc; 671 672 // Keep track of the code space start and end pointers in case new 673 // code objects were unserialized 674 OldSpace* code_space = isolate_->heap()->code_space(); 675 Address start_address = code_space->top(); 676 VisitPointer(root); 677 678 // There's no code deserialized here. If this assert fires 679 // then that's changed and logging should be added to notify 680 // the profiler et al of the new code. 681 CHECK_EQ(start_address, code_space->top()); 682 } 683 684 685 Deserializer::~Deserializer() { 686 // TODO(svenpanne) Re-enable this assertion when v8 initialization is fixed. 687 // DCHECK(source_->AtEOF()); 688 if (external_reference_decoder_) { 689 delete external_reference_decoder_; 690 external_reference_decoder_ = NULL; 691 } 692 if (attached_objects_) attached_objects_->Dispose(); 693 } 694 695 696 // This is called on the roots. It is the driver of the deserialization 697 // process. It is also called on the body of each function. 698 void Deserializer::VisitPointers(Object** start, Object** end) { 699 // The space must be new space. Any other space would cause ReadChunk to try 700 // to update the remembered using NULL as the address. 701 ReadChunk(start, end, NEW_SPACE, NULL); 702 } 703 704 705 void Deserializer::RelinkAllocationSite(AllocationSite* site) { 706 if (isolate_->heap()->allocation_sites_list() == Smi::FromInt(0)) { 707 site->set_weak_next(isolate_->heap()->undefined_value()); 708 } else { 709 site->set_weak_next(isolate_->heap()->allocation_sites_list()); 710 } 711 isolate_->heap()->set_allocation_sites_list(site); 712 } 713 714 715 // Used to insert a deserialized internalized string into the string table. 716 class StringTableInsertionKey : public HashTableKey { 717 public: 718 explicit StringTableInsertionKey(String* string) 719 : string_(string), hash_(HashForObject(string)) { 720 DCHECK(string->IsInternalizedString()); 721 } 722 723 virtual bool IsMatch(Object* string) { 724 // We know that all entries in a hash table had their hash keys created. 725 // Use that knowledge to have fast failure. 726 if (hash_ != HashForObject(string)) return false; 727 // We want to compare the content of two internalized strings here. 728 return string_->SlowEquals(String::cast(string)); 729 } 730 731 virtual uint32_t Hash() OVERRIDE { return hash_; } 732 733 virtual uint32_t HashForObject(Object* key) OVERRIDE { 734 return String::cast(key)->Hash(); 735 } 736 737 MUST_USE_RESULT virtual Handle<Object> AsHandle(Isolate* isolate) 738 OVERRIDE { 739 return handle(string_, isolate); 740 } 741 742 String* string_; 743 uint32_t hash_; 744 }; 745 746 747 HeapObject* Deserializer::ProcessNewObjectFromSerializedCode(HeapObject* obj) { 748 if (obj->IsString()) { 749 String* string = String::cast(obj); 750 // Uninitialize hash field as the hash seed may have changed. 751 string->set_hash_field(String::kEmptyHashField); 752 if (string->IsInternalizedString()) { 753 DisallowHeapAllocation no_gc; 754 HandleScope scope(isolate_); 755 StringTableInsertionKey key(string); 756 String* canonical = *StringTable::LookupKey(isolate_, &key); 757 string->SetForwardedInternalizedString(canonical); 758 return canonical; 759 } 760 } 761 return obj; 762 } 763 764 765 Object* Deserializer::ProcessBackRefInSerializedCode(Object* obj) { 766 if (obj->IsInternalizedString()) { 767 return String::cast(obj)->GetForwardedInternalizedString(); 768 } 769 return obj; 770 } 771 772 773 // This routine writes the new object into the pointer provided and then 774 // returns true if the new object was in young space and false otherwise. 775 // The reason for this strange interface is that otherwise the object is 776 // written very late, which means the FreeSpace map is not set up by the 777 // time we need to use it to mark the space at the end of a page free. 778 void Deserializer::ReadObject(int space_number, 779 Object** write_back) { 780 int size = source_->GetInt() << kObjectAlignmentBits; 781 Address address = Allocate(space_number, size); 782 HeapObject* obj = HeapObject::FromAddress(address); 783 isolate_->heap()->OnAllocationEvent(obj, size); 784 Object** current = reinterpret_cast<Object**>(address); 785 Object** limit = current + (size >> kPointerSizeLog2); 786 if (FLAG_log_snapshot_positions) { 787 LOG(isolate_, SnapshotPositionEvent(address, source_->position())); 788 } 789 ReadChunk(current, limit, space_number, address); 790 791 // TODO(mvstanton): consider treating the heap()->allocation_sites_list() 792 // as a (weak) root. If this root is relocated correctly, 793 // RelinkAllocationSite() isn't necessary. 794 if (obj->IsAllocationSite()) RelinkAllocationSite(AllocationSite::cast(obj)); 795 796 // Fix up strings from serialized user code. 797 if (deserializing_user_code()) obj = ProcessNewObjectFromSerializedCode(obj); 798 799 *write_back = obj; 800 #ifdef DEBUG 801 bool is_codespace = (space_number == CODE_SPACE); 802 DCHECK(obj->IsCode() == is_codespace); 803 #endif 804 } 805 806 void Deserializer::ReadChunk(Object** current, 807 Object** limit, 808 int source_space, 809 Address current_object_address) { 810 Isolate* const isolate = isolate_; 811 // Write barrier support costs around 1% in startup time. In fact there 812 // are no new space objects in current boot snapshots, so it's not needed, 813 // but that may change. 814 bool write_barrier_needed = (current_object_address != NULL && 815 source_space != NEW_SPACE && 816 source_space != CELL_SPACE && 817 source_space != PROPERTY_CELL_SPACE && 818 source_space != CODE_SPACE && 819 source_space != OLD_DATA_SPACE); 820 while (current < limit) { 821 int data = source_->Get(); 822 switch (data) { 823 #define CASE_STATEMENT(where, how, within, space_number) \ 824 case where + how + within + space_number: \ 825 STATIC_ASSERT((where & ~kPointedToMask) == 0); \ 826 STATIC_ASSERT((how & ~kHowToCodeMask) == 0); \ 827 STATIC_ASSERT((within & ~kWhereToPointMask) == 0); \ 828 STATIC_ASSERT((space_number & ~kSpaceMask) == 0); 829 830 #define CASE_BODY(where, how, within, space_number_if_any) \ 831 { \ 832 bool emit_write_barrier = false; \ 833 bool current_was_incremented = false; \ 834 int space_number = space_number_if_any == kAnyOldSpace \ 835 ? (data & kSpaceMask) \ 836 : space_number_if_any; \ 837 if (where == kNewObject && how == kPlain && within == kStartOfObject) { \ 838 ReadObject(space_number, current); \ 839 emit_write_barrier = (space_number == NEW_SPACE); \ 840 } else { \ 841 Object* new_object = NULL; /* May not be a real Object pointer. */ \ 842 if (where == kNewObject) { \ 843 ReadObject(space_number, &new_object); \ 844 } else if (where == kRootArray) { \ 845 int root_id = source_->GetInt(); \ 846 new_object = isolate->heap()->roots_array_start()[root_id]; \ 847 emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ 848 } else if (where == kPartialSnapshotCache) { \ 849 int cache_index = source_->GetInt(); \ 850 new_object = isolate->serialize_partial_snapshot_cache()[cache_index]; \ 851 emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ 852 } else if (where == kExternalReference) { \ 853 int skip = source_->GetInt(); \ 854 current = reinterpret_cast<Object**>( \ 855 reinterpret_cast<Address>(current) + skip); \ 856 int reference_id = source_->GetInt(); \ 857 Address address = external_reference_decoder_->Decode(reference_id); \ 858 new_object = reinterpret_cast<Object*>(address); \ 859 } else if (where == kBackref) { \ 860 emit_write_barrier = (space_number == NEW_SPACE); \ 861 new_object = GetAddressFromEnd(data & kSpaceMask); \ 862 if (deserializing_user_code()) { \ 863 new_object = ProcessBackRefInSerializedCode(new_object); \ 864 } \ 865 } else if (where == kBuiltin) { \ 866 DCHECK(deserializing_user_code()); \ 867 int builtin_id = source_->GetInt(); \ 868 DCHECK_LE(0, builtin_id); \ 869 DCHECK_LT(builtin_id, Builtins::builtin_count); \ 870 Builtins::Name name = static_cast<Builtins::Name>(builtin_id); \ 871 new_object = isolate->builtins()->builtin(name); \ 872 emit_write_barrier = false; \ 873 } else if (where == kAttachedReference) { \ 874 DCHECK(deserializing_user_code()); \ 875 int index = source_->GetInt(); \ 876 new_object = *attached_objects_->at(index); \ 877 emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ 878 } else { \ 879 DCHECK(where == kBackrefWithSkip); \ 880 int skip = source_->GetInt(); \ 881 current = reinterpret_cast<Object**>( \ 882 reinterpret_cast<Address>(current) + skip); \ 883 emit_write_barrier = (space_number == NEW_SPACE); \ 884 new_object = GetAddressFromEnd(data & kSpaceMask); \ 885 if (deserializing_user_code()) { \ 886 new_object = ProcessBackRefInSerializedCode(new_object); \ 887 } \ 888 } \ 889 if (within == kInnerPointer) { \ 890 if (space_number != CODE_SPACE || new_object->IsCode()) { \ 891 Code* new_code_object = reinterpret_cast<Code*>(new_object); \ 892 new_object = \ 893 reinterpret_cast<Object*>(new_code_object->instruction_start()); \ 894 } else { \ 895 DCHECK(space_number == CODE_SPACE); \ 896 Cell* cell = Cell::cast(new_object); \ 897 new_object = reinterpret_cast<Object*>(cell->ValueAddress()); \ 898 } \ 899 } \ 900 if (how == kFromCode) { \ 901 Address location_of_branch_data = reinterpret_cast<Address>(current); \ 902 Assembler::deserialization_set_special_target_at( \ 903 location_of_branch_data, \ 904 Code::cast(HeapObject::FromAddress(current_object_address)), \ 905 reinterpret_cast<Address>(new_object)); \ 906 location_of_branch_data += Assembler::kSpecialTargetSize; \ 907 current = reinterpret_cast<Object**>(location_of_branch_data); \ 908 current_was_incremented = true; \ 909 } else { \ 910 *current = new_object; \ 911 } \ 912 } \ 913 if (emit_write_barrier && write_barrier_needed) { \ 914 Address current_address = reinterpret_cast<Address>(current); \ 915 isolate->heap()->RecordWrite( \ 916 current_object_address, \ 917 static_cast<int>(current_address - current_object_address)); \ 918 } \ 919 if (!current_was_incremented) { \ 920 current++; \ 921 } \ 922 break; \ 923 } 924 925 // This generates a case and a body for the new space (which has to do extra 926 // write barrier handling) and handles the other spaces with 8 fall-through 927 // cases and one body. 928 #define ALL_SPACES(where, how, within) \ 929 CASE_STATEMENT(where, how, within, NEW_SPACE) \ 930 CASE_BODY(where, how, within, NEW_SPACE) \ 931 CASE_STATEMENT(where, how, within, OLD_DATA_SPACE) \ 932 CASE_STATEMENT(where, how, within, OLD_POINTER_SPACE) \ 933 CASE_STATEMENT(where, how, within, CODE_SPACE) \ 934 CASE_STATEMENT(where, how, within, CELL_SPACE) \ 935 CASE_STATEMENT(where, how, within, PROPERTY_CELL_SPACE) \ 936 CASE_STATEMENT(where, how, within, MAP_SPACE) \ 937 CASE_BODY(where, how, within, kAnyOldSpace) 938 939 #define FOUR_CASES(byte_code) \ 940 case byte_code: \ 941 case byte_code + 1: \ 942 case byte_code + 2: \ 943 case byte_code + 3: 944 945 #define SIXTEEN_CASES(byte_code) \ 946 FOUR_CASES(byte_code) \ 947 FOUR_CASES(byte_code + 4) \ 948 FOUR_CASES(byte_code + 8) \ 949 FOUR_CASES(byte_code + 12) 950 951 #define COMMON_RAW_LENGTHS(f) \ 952 f(1) \ 953 f(2) \ 954 f(3) \ 955 f(4) \ 956 f(5) \ 957 f(6) \ 958 f(7) \ 959 f(8) \ 960 f(9) \ 961 f(10) \ 962 f(11) \ 963 f(12) \ 964 f(13) \ 965 f(14) \ 966 f(15) \ 967 f(16) \ 968 f(17) \ 969 f(18) \ 970 f(19) \ 971 f(20) \ 972 f(21) \ 973 f(22) \ 974 f(23) \ 975 f(24) \ 976 f(25) \ 977 f(26) \ 978 f(27) \ 979 f(28) \ 980 f(29) \ 981 f(30) \ 982 f(31) 983 984 // We generate 15 cases and bodies that process special tags that combine 985 // the raw data tag and the length into one byte. 986 #define RAW_CASE(index) \ 987 case kRawData + index: { \ 988 byte* raw_data_out = reinterpret_cast<byte*>(current); \ 989 source_->CopyRaw(raw_data_out, index * kPointerSize); \ 990 current = \ 991 reinterpret_cast<Object**>(raw_data_out + index * kPointerSize); \ 992 break; \ 993 } 994 COMMON_RAW_LENGTHS(RAW_CASE) 995 #undef RAW_CASE 996 997 // Deserialize a chunk of raw data that doesn't have one of the popular 998 // lengths. 999 case kRawData: { 1000 int size = source_->GetInt(); 1001 byte* raw_data_out = reinterpret_cast<byte*>(current); 1002 source_->CopyRaw(raw_data_out, size); 1003 break; 1004 } 1005 1006 SIXTEEN_CASES(kRootArrayConstants + kNoSkipDistance) 1007 SIXTEEN_CASES(kRootArrayConstants + kNoSkipDistance + 16) { 1008 int root_id = RootArrayConstantFromByteCode(data); 1009 Object* object = isolate->heap()->roots_array_start()[root_id]; 1010 DCHECK(!isolate->heap()->InNewSpace(object)); 1011 *current++ = object; 1012 break; 1013 } 1014 1015 SIXTEEN_CASES(kRootArrayConstants + kHasSkipDistance) 1016 SIXTEEN_CASES(kRootArrayConstants + kHasSkipDistance + 16) { 1017 int root_id = RootArrayConstantFromByteCode(data); 1018 int skip = source_->GetInt(); 1019 current = reinterpret_cast<Object**>( 1020 reinterpret_cast<intptr_t>(current) + skip); 1021 Object* object = isolate->heap()->roots_array_start()[root_id]; 1022 DCHECK(!isolate->heap()->InNewSpace(object)); 1023 *current++ = object; 1024 break; 1025 } 1026 1027 case kRepeat: { 1028 int repeats = source_->GetInt(); 1029 Object* object = current[-1]; 1030 DCHECK(!isolate->heap()->InNewSpace(object)); 1031 for (int i = 0; i < repeats; i++) current[i] = object; 1032 current += repeats; 1033 break; 1034 } 1035 1036 STATIC_ASSERT(kRootArrayNumberOfConstantEncodings == 1037 Heap::kOldSpaceRoots); 1038 STATIC_ASSERT(kMaxRepeats == 13); 1039 case kConstantRepeat: 1040 FOUR_CASES(kConstantRepeat + 1) 1041 FOUR_CASES(kConstantRepeat + 5) 1042 FOUR_CASES(kConstantRepeat + 9) { 1043 int repeats = RepeatsForCode(data); 1044 Object* object = current[-1]; 1045 DCHECK(!isolate->heap()->InNewSpace(object)); 1046 for (int i = 0; i < repeats; i++) current[i] = object; 1047 current += repeats; 1048 break; 1049 } 1050 1051 // Deserialize a new object and write a pointer to it to the current 1052 // object. 1053 ALL_SPACES(kNewObject, kPlain, kStartOfObject) 1054 // Support for direct instruction pointers in functions. It's an inner 1055 // pointer because it points at the entry point, not at the start of the 1056 // code object. 1057 CASE_STATEMENT(kNewObject, kPlain, kInnerPointer, CODE_SPACE) 1058 CASE_BODY(kNewObject, kPlain, kInnerPointer, CODE_SPACE) 1059 // Deserialize a new code object and write a pointer to its first 1060 // instruction to the current code object. 1061 ALL_SPACES(kNewObject, kFromCode, kInnerPointer) 1062 // Find a recently deserialized object using its offset from the current 1063 // allocation point and write a pointer to it to the current object. 1064 ALL_SPACES(kBackref, kPlain, kStartOfObject) 1065 ALL_SPACES(kBackrefWithSkip, kPlain, kStartOfObject) 1066 #if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL || \ 1067 defined(V8_TARGET_ARCH_MIPS64) 1068 // Deserialize a new object from pointer found in code and write 1069 // a pointer to it to the current object. Required only for MIPS or ARM 1070 // with ool constant pool, and omitted on the other architectures because 1071 // it is fully unrolled and would cause bloat. 1072 ALL_SPACES(kNewObject, kFromCode, kStartOfObject) 1073 // Find a recently deserialized code object using its offset from the 1074 // current allocation point and write a pointer to it to the current 1075 // object. Required only for MIPS or ARM with ool constant pool. 1076 ALL_SPACES(kBackref, kFromCode, kStartOfObject) 1077 ALL_SPACES(kBackrefWithSkip, kFromCode, kStartOfObject) 1078 #endif 1079 // Find a recently deserialized code object using its offset from the 1080 // current allocation point and write a pointer to its first instruction 1081 // to the current code object or the instruction pointer in a function 1082 // object. 1083 ALL_SPACES(kBackref, kFromCode, kInnerPointer) 1084 ALL_SPACES(kBackrefWithSkip, kFromCode, kInnerPointer) 1085 ALL_SPACES(kBackref, kPlain, kInnerPointer) 1086 ALL_SPACES(kBackrefWithSkip, kPlain, kInnerPointer) 1087 // Find an object in the roots array and write a pointer to it to the 1088 // current object. 1089 CASE_STATEMENT(kRootArray, kPlain, kStartOfObject, 0) 1090 CASE_BODY(kRootArray, kPlain, kStartOfObject, 0) 1091 #if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL || \ 1092 defined(V8_TARGET_ARCH_MIPS64) 1093 // Find an object in the roots array and write a pointer to it to in code. 1094 CASE_STATEMENT(kRootArray, kFromCode, kStartOfObject, 0) 1095 CASE_BODY(kRootArray, kFromCode, kStartOfObject, 0) 1096 #endif 1097 // Find an object in the partial snapshots cache and write a pointer to it 1098 // to the current object. 1099 CASE_STATEMENT(kPartialSnapshotCache, kPlain, kStartOfObject, 0) 1100 CASE_BODY(kPartialSnapshotCache, 1101 kPlain, 1102 kStartOfObject, 1103 0) 1104 // Find an code entry in the partial snapshots cache and 1105 // write a pointer to it to the current object. 1106 CASE_STATEMENT(kPartialSnapshotCache, kPlain, kInnerPointer, 0) 1107 CASE_BODY(kPartialSnapshotCache, 1108 kPlain, 1109 kInnerPointer, 1110 0) 1111 // Find an external reference and write a pointer to it to the current 1112 // object. 1113 CASE_STATEMENT(kExternalReference, kPlain, kStartOfObject, 0) 1114 CASE_BODY(kExternalReference, 1115 kPlain, 1116 kStartOfObject, 1117 0) 1118 // Find an external reference and write a pointer to it in the current 1119 // code object. 1120 CASE_STATEMENT(kExternalReference, kFromCode, kStartOfObject, 0) 1121 CASE_BODY(kExternalReference, 1122 kFromCode, 1123 kStartOfObject, 1124 0) 1125 // Find a builtin and write a pointer to it to the current object. 1126 CASE_STATEMENT(kBuiltin, kPlain, kStartOfObject, 0) 1127 CASE_BODY(kBuiltin, kPlain, kStartOfObject, 0) 1128 #if V8_OOL_CONSTANT_POOL 1129 // Find a builtin code entry and write a pointer to it to the current 1130 // object. 1131 CASE_STATEMENT(kBuiltin, kPlain, kInnerPointer, 0) 1132 CASE_BODY(kBuiltin, kPlain, kInnerPointer, 0) 1133 #endif 1134 // Find a builtin and write a pointer to it in the current code object. 1135 CASE_STATEMENT(kBuiltin, kFromCode, kInnerPointer, 0) 1136 CASE_BODY(kBuiltin, kFromCode, kInnerPointer, 0) 1137 // Find an object in the attached references and write a pointer to it to 1138 // the current object. 1139 CASE_STATEMENT(kAttachedReference, kPlain, kStartOfObject, 0) 1140 CASE_BODY(kAttachedReference, kPlain, kStartOfObject, 0) 1141 CASE_STATEMENT(kAttachedReference, kPlain, kInnerPointer, 0) 1142 CASE_BODY(kAttachedReference, kPlain, kInnerPointer, 0) 1143 CASE_STATEMENT(kAttachedReference, kFromCode, kInnerPointer, 0) 1144 CASE_BODY(kAttachedReference, kFromCode, kInnerPointer, 0) 1145 1146 #undef CASE_STATEMENT 1147 #undef CASE_BODY 1148 #undef ALL_SPACES 1149 1150 case kSkip: { 1151 int size = source_->GetInt(); 1152 current = reinterpret_cast<Object**>( 1153 reinterpret_cast<intptr_t>(current) + size); 1154 break; 1155 } 1156 1157 case kNativesStringResource: { 1158 int index = source_->Get(); 1159 Vector<const char> source_vector = Natives::GetRawScriptSource(index); 1160 NativesExternalStringResource* resource = 1161 new NativesExternalStringResource(isolate->bootstrapper(), 1162 source_vector.start(), 1163 source_vector.length()); 1164 *current++ = reinterpret_cast<Object*>(resource); 1165 break; 1166 } 1167 1168 case kSynchronize: { 1169 // If we get here then that indicates that you have a mismatch between 1170 // the number of GC roots when serializing and deserializing. 1171 UNREACHABLE(); 1172 } 1173 1174 default: 1175 UNREACHABLE(); 1176 } 1177 } 1178 DCHECK_EQ(limit, current); 1179 } 1180 1181 1182 Serializer::Serializer(Isolate* isolate, SnapshotByteSink* sink) 1183 : isolate_(isolate), 1184 sink_(sink), 1185 external_reference_encoder_(new ExternalReferenceEncoder(isolate)), 1186 root_index_wave_front_(0), 1187 code_address_map_(NULL) { 1188 // The serializer is meant to be used only to generate initial heap images 1189 // from a context in which there is only one isolate. 1190 for (int i = 0; i <= LAST_SPACE; i++) { 1191 fullness_[i] = 0; 1192 } 1193 } 1194 1195 1196 Serializer::~Serializer() { 1197 delete external_reference_encoder_; 1198 if (code_address_map_ != NULL) delete code_address_map_; 1199 } 1200 1201 1202 void StartupSerializer::SerializeStrongReferences() { 1203 Isolate* isolate = this->isolate(); 1204 // No active threads. 1205 CHECK_EQ(NULL, isolate->thread_manager()->FirstThreadStateInUse()); 1206 // No active or weak handles. 1207 CHECK(isolate->handle_scope_implementer()->blocks()->is_empty()); 1208 CHECK_EQ(0, isolate->global_handles()->NumberOfWeakHandles()); 1209 CHECK_EQ(0, isolate->eternal_handles()->NumberOfHandles()); 1210 // We don't support serializing installed extensions. 1211 CHECK(!isolate->has_installed_extensions()); 1212 isolate->heap()->IterateSmiRoots(this); 1213 isolate->heap()->IterateStrongRoots(this, VISIT_ONLY_STRONG); 1214 } 1215 1216 1217 void PartialSerializer::Serialize(Object** object) { 1218 this->VisitPointer(object); 1219 Pad(); 1220 } 1221 1222 1223 bool Serializer::ShouldBeSkipped(Object** current) { 1224 Object** roots = isolate()->heap()->roots_array_start(); 1225 return current == &roots[Heap::kStoreBufferTopRootIndex] 1226 || current == &roots[Heap::kStackLimitRootIndex] 1227 || current == &roots[Heap::kRealStackLimitRootIndex]; 1228 } 1229 1230 1231 void Serializer::VisitPointers(Object** start, Object** end) { 1232 Isolate* isolate = this->isolate();; 1233 1234 for (Object** current = start; current < end; current++) { 1235 if (start == isolate->heap()->roots_array_start()) { 1236 root_index_wave_front_ = 1237 Max(root_index_wave_front_, static_cast<intptr_t>(current - start)); 1238 } 1239 if (ShouldBeSkipped(current)) { 1240 sink_->Put(kSkip, "Skip"); 1241 sink_->PutInt(kPointerSize, "SkipOneWord"); 1242 } else if ((*current)->IsSmi()) { 1243 sink_->Put(kRawData + 1, "Smi"); 1244 for (int i = 0; i < kPointerSize; i++) { 1245 sink_->Put(reinterpret_cast<byte*>(current)[i], "Byte"); 1246 } 1247 } else { 1248 SerializeObject(*current, kPlain, kStartOfObject, 0); 1249 } 1250 } 1251 } 1252 1253 1254 // This ensures that the partial snapshot cache keeps things alive during GC and 1255 // tracks their movement. When it is called during serialization of the startup 1256 // snapshot nothing happens. When the partial (context) snapshot is created, 1257 // this array is populated with the pointers that the partial snapshot will 1258 // need. As that happens we emit serialized objects to the startup snapshot 1259 // that correspond to the elements of this cache array. On deserialization we 1260 // therefore need to visit the cache array. This fills it up with pointers to 1261 // deserialized objects. 1262 void SerializerDeserializer::Iterate(Isolate* isolate, 1263 ObjectVisitor* visitor) { 1264 if (isolate->serializer_enabled()) return; 1265 for (int i = 0; ; i++) { 1266 if (isolate->serialize_partial_snapshot_cache_length() <= i) { 1267 // Extend the array ready to get a value from the visitor when 1268 // deserializing. 1269 isolate->PushToPartialSnapshotCache(Smi::FromInt(0)); 1270 } 1271 Object** cache = isolate->serialize_partial_snapshot_cache(); 1272 visitor->VisitPointers(&cache[i], &cache[i + 1]); 1273 // Sentinel is the undefined object, which is a root so it will not normally 1274 // be found in the cache. 1275 if (cache[i] == isolate->heap()->undefined_value()) { 1276 break; 1277 } 1278 } 1279 } 1280 1281 1282 int PartialSerializer::PartialSnapshotCacheIndex(HeapObject* heap_object) { 1283 Isolate* isolate = this->isolate(); 1284 1285 for (int i = 0; 1286 i < isolate->serialize_partial_snapshot_cache_length(); 1287 i++) { 1288 Object* entry = isolate->serialize_partial_snapshot_cache()[i]; 1289 if (entry == heap_object) return i; 1290 } 1291 1292 // We didn't find the object in the cache. So we add it to the cache and 1293 // then visit the pointer so that it becomes part of the startup snapshot 1294 // and we can refer to it from the partial snapshot. 1295 int length = isolate->serialize_partial_snapshot_cache_length(); 1296 isolate->PushToPartialSnapshotCache(heap_object); 1297 startup_serializer_->VisitPointer(reinterpret_cast<Object**>(&heap_object)); 1298 // We don't recurse from the startup snapshot generator into the partial 1299 // snapshot generator. 1300 DCHECK(length == isolate->serialize_partial_snapshot_cache_length() - 1); 1301 return length; 1302 } 1303 1304 1305 int Serializer::RootIndex(HeapObject* heap_object, HowToCode from) { 1306 Heap* heap = isolate()->heap(); 1307 if (heap->InNewSpace(heap_object)) return kInvalidRootIndex; 1308 for (int i = 0; i < root_index_wave_front_; i++) { 1309 Object* root = heap->roots_array_start()[i]; 1310 if (!root->IsSmi() && root == heap_object) { 1311 return i; 1312 } 1313 } 1314 return kInvalidRootIndex; 1315 } 1316 1317 1318 // Encode the location of an already deserialized object in order to write its 1319 // location into a later object. We can encode the location as an offset from 1320 // the start of the deserialized objects or as an offset backwards from the 1321 // current allocation pointer. 1322 void Serializer::SerializeReferenceToPreviousObject(HeapObject* heap_object, 1323 HowToCode how_to_code, 1324 WhereToPoint where_to_point, 1325 int skip) { 1326 int space = SpaceOfObject(heap_object); 1327 int address = address_mapper_.MappedTo(heap_object); 1328 int offset = CurrentAllocationAddress(space) - address; 1329 // Shift out the bits that are always 0. 1330 offset >>= kObjectAlignmentBits; 1331 if (skip == 0) { 1332 sink_->Put(kBackref + how_to_code + where_to_point + space, "BackRefSer"); 1333 } else { 1334 sink_->Put(kBackrefWithSkip + how_to_code + where_to_point + space, 1335 "BackRefSerWithSkip"); 1336 sink_->PutInt(skip, "BackRefSkipDistance"); 1337 } 1338 sink_->PutInt(offset, "offset"); 1339 } 1340 1341 1342 void StartupSerializer::SerializeObject( 1343 Object* o, 1344 HowToCode how_to_code, 1345 WhereToPoint where_to_point, 1346 int skip) { 1347 CHECK(o->IsHeapObject()); 1348 HeapObject* heap_object = HeapObject::cast(o); 1349 DCHECK(!heap_object->IsJSFunction()); 1350 1351 int root_index; 1352 if ((root_index = RootIndex(heap_object, how_to_code)) != kInvalidRootIndex) { 1353 PutRoot(root_index, heap_object, how_to_code, where_to_point, skip); 1354 return; 1355 } 1356 1357 if (address_mapper_.IsMapped(heap_object)) { 1358 SerializeReferenceToPreviousObject(heap_object, how_to_code, where_to_point, 1359 skip); 1360 } else { 1361 if (skip != 0) { 1362 sink_->Put(kSkip, "FlushPendingSkip"); 1363 sink_->PutInt(skip, "SkipDistance"); 1364 } 1365 1366 // Object has not yet been serialized. Serialize it here. 1367 ObjectSerializer object_serializer(this, 1368 heap_object, 1369 sink_, 1370 how_to_code, 1371 where_to_point); 1372 object_serializer.Serialize(); 1373 } 1374 } 1375 1376 1377 void StartupSerializer::SerializeWeakReferences() { 1378 // This phase comes right after the partial serialization (of the snapshot). 1379 // After we have done the partial serialization the partial snapshot cache 1380 // will contain some references needed to decode the partial snapshot. We 1381 // add one entry with 'undefined' which is the sentinel that the deserializer 1382 // uses to know it is done deserializing the array. 1383 Object* undefined = isolate()->heap()->undefined_value(); 1384 VisitPointer(&undefined); 1385 isolate()->heap()->IterateWeakRoots(this, VISIT_ALL); 1386 Pad(); 1387 } 1388 1389 1390 void Serializer::PutRoot(int root_index, 1391 HeapObject* object, 1392 SerializerDeserializer::HowToCode how_to_code, 1393 SerializerDeserializer::WhereToPoint where_to_point, 1394 int skip) { 1395 if (how_to_code == kPlain && 1396 where_to_point == kStartOfObject && 1397 root_index < kRootArrayNumberOfConstantEncodings && 1398 !isolate()->heap()->InNewSpace(object)) { 1399 if (skip == 0) { 1400 sink_->Put(kRootArrayConstants + kNoSkipDistance + root_index, 1401 "RootConstant"); 1402 } else { 1403 sink_->Put(kRootArrayConstants + kHasSkipDistance + root_index, 1404 "RootConstant"); 1405 sink_->PutInt(skip, "SkipInPutRoot"); 1406 } 1407 } else { 1408 if (skip != 0) { 1409 sink_->Put(kSkip, "SkipFromPutRoot"); 1410 sink_->PutInt(skip, "SkipFromPutRootDistance"); 1411 } 1412 sink_->Put(kRootArray + how_to_code + where_to_point, "RootSerialization"); 1413 sink_->PutInt(root_index, "root_index"); 1414 } 1415 } 1416 1417 1418 void PartialSerializer::SerializeObject( 1419 Object* o, 1420 HowToCode how_to_code, 1421 WhereToPoint where_to_point, 1422 int skip) { 1423 CHECK(o->IsHeapObject()); 1424 HeapObject* heap_object = HeapObject::cast(o); 1425 1426 if (heap_object->IsMap()) { 1427 // The code-caches link to context-specific code objects, which 1428 // the startup and context serializes cannot currently handle. 1429 DCHECK(Map::cast(heap_object)->code_cache() == 1430 heap_object->GetHeap()->empty_fixed_array()); 1431 } 1432 1433 int root_index; 1434 if ((root_index = RootIndex(heap_object, how_to_code)) != kInvalidRootIndex) { 1435 PutRoot(root_index, heap_object, how_to_code, where_to_point, skip); 1436 return; 1437 } 1438 1439 if (ShouldBeInThePartialSnapshotCache(heap_object)) { 1440 if (skip != 0) { 1441 sink_->Put(kSkip, "SkipFromSerializeObject"); 1442 sink_->PutInt(skip, "SkipDistanceFromSerializeObject"); 1443 } 1444 1445 int cache_index = PartialSnapshotCacheIndex(heap_object); 1446 sink_->Put(kPartialSnapshotCache + how_to_code + where_to_point, 1447 "PartialSnapshotCache"); 1448 sink_->PutInt(cache_index, "partial_snapshot_cache_index"); 1449 return; 1450 } 1451 1452 // Pointers from the partial snapshot to the objects in the startup snapshot 1453 // should go through the root array or through the partial snapshot cache. 1454 // If this is not the case you may have to add something to the root array. 1455 DCHECK(!startup_serializer_->address_mapper()->IsMapped(heap_object)); 1456 // All the internalized strings that the partial snapshot needs should be 1457 // either in the root table or in the partial snapshot cache. 1458 DCHECK(!heap_object->IsInternalizedString()); 1459 1460 if (address_mapper_.IsMapped(heap_object)) { 1461 SerializeReferenceToPreviousObject(heap_object, how_to_code, where_to_point, 1462 skip); 1463 } else { 1464 if (skip != 0) { 1465 sink_->Put(kSkip, "SkipFromSerializeObject"); 1466 sink_->PutInt(skip, "SkipDistanceFromSerializeObject"); 1467 } 1468 // Object has not yet been serialized. Serialize it here. 1469 ObjectSerializer serializer(this, 1470 heap_object, 1471 sink_, 1472 how_to_code, 1473 where_to_point); 1474 serializer.Serialize(); 1475 } 1476 } 1477 1478 1479 void Serializer::ObjectSerializer::Serialize() { 1480 int space = Serializer::SpaceOfObject(object_); 1481 int size = object_->Size(); 1482 1483 sink_->Put(kNewObject + reference_representation_ + space, 1484 "ObjectSerialization"); 1485 sink_->PutInt(size >> kObjectAlignmentBits, "Size in words"); 1486 1487 if (serializer_->code_address_map_) { 1488 const char* code_name = 1489 serializer_->code_address_map_->Lookup(object_->address()); 1490 LOG(serializer_->isolate_, 1491 CodeNameEvent(object_->address(), sink_->Position(), code_name)); 1492 LOG(serializer_->isolate_, 1493 SnapshotPositionEvent(object_->address(), sink_->Position())); 1494 } 1495 1496 // Mark this object as already serialized. 1497 int offset = serializer_->Allocate(space, size); 1498 serializer_->address_mapper()->AddMapping(object_, offset); 1499 1500 // Serialize the map (first word of the object). 1501 serializer_->SerializeObject(object_->map(), kPlain, kStartOfObject, 0); 1502 1503 // Serialize the rest of the object. 1504 CHECK_EQ(0, bytes_processed_so_far_); 1505 bytes_processed_so_far_ = kPointerSize; 1506 object_->IterateBody(object_->map()->instance_type(), size, this); 1507 OutputRawData(object_->address() + size); 1508 } 1509 1510 1511 void Serializer::ObjectSerializer::VisitPointers(Object** start, 1512 Object** end) { 1513 Object** current = start; 1514 while (current < end) { 1515 while (current < end && (*current)->IsSmi()) current++; 1516 if (current < end) OutputRawData(reinterpret_cast<Address>(current)); 1517 1518 while (current < end && !(*current)->IsSmi()) { 1519 HeapObject* current_contents = HeapObject::cast(*current); 1520 int root_index = serializer_->RootIndex(current_contents, kPlain); 1521 // Repeats are not subject to the write barrier so there are only some 1522 // objects that can be used in a repeat encoding. These are the early 1523 // ones in the root array that are never in new space. 1524 if (current != start && 1525 root_index != kInvalidRootIndex && 1526 root_index < kRootArrayNumberOfConstantEncodings && 1527 current_contents == current[-1]) { 1528 DCHECK(!serializer_->isolate()->heap()->InNewSpace(current_contents)); 1529 int repeat_count = 1; 1530 while (¤t[repeat_count] < end - 1 && 1531 current[repeat_count] == current_contents) { 1532 repeat_count++; 1533 } 1534 current += repeat_count; 1535 bytes_processed_so_far_ += repeat_count * kPointerSize; 1536 if (repeat_count > kMaxRepeats) { 1537 sink_->Put(kRepeat, "SerializeRepeats"); 1538 sink_->PutInt(repeat_count, "SerializeRepeats"); 1539 } else { 1540 sink_->Put(CodeForRepeats(repeat_count), "SerializeRepeats"); 1541 } 1542 } else { 1543 serializer_->SerializeObject( 1544 current_contents, kPlain, kStartOfObject, 0); 1545 bytes_processed_so_far_ += kPointerSize; 1546 current++; 1547 } 1548 } 1549 } 1550 } 1551 1552 1553 void Serializer::ObjectSerializer::VisitEmbeddedPointer(RelocInfo* rinfo) { 1554 // Out-of-line constant pool entries will be visited by the ConstantPoolArray. 1555 if (FLAG_enable_ool_constant_pool && rinfo->IsInConstantPool()) return; 1556 1557 int skip = OutputRawData(rinfo->target_address_address(), 1558 kCanReturnSkipInsteadOfSkipping); 1559 HowToCode how_to_code = rinfo->IsCodedSpecially() ? kFromCode : kPlain; 1560 Object* object = rinfo->target_object(); 1561 serializer_->SerializeObject(object, how_to_code, kStartOfObject, skip); 1562 bytes_processed_so_far_ += rinfo->target_address_size(); 1563 } 1564 1565 1566 void Serializer::ObjectSerializer::VisitExternalReference(Address* p) { 1567 int skip = OutputRawData(reinterpret_cast<Address>(p), 1568 kCanReturnSkipInsteadOfSkipping); 1569 sink_->Put(kExternalReference + kPlain + kStartOfObject, "ExternalRef"); 1570 sink_->PutInt(skip, "SkipB4ExternalRef"); 1571 Address target = *p; 1572 sink_->PutInt(serializer_->EncodeExternalReference(target), "reference id"); 1573 bytes_processed_so_far_ += kPointerSize; 1574 } 1575 1576 1577 void Serializer::ObjectSerializer::VisitExternalReference(RelocInfo* rinfo) { 1578 int skip = OutputRawData(rinfo->target_address_address(), 1579 kCanReturnSkipInsteadOfSkipping); 1580 HowToCode how_to_code = rinfo->IsCodedSpecially() ? kFromCode : kPlain; 1581 sink_->Put(kExternalReference + how_to_code + kStartOfObject, "ExternalRef"); 1582 sink_->PutInt(skip, "SkipB4ExternalRef"); 1583 Address target = rinfo->target_reference(); 1584 sink_->PutInt(serializer_->EncodeExternalReference(target), "reference id"); 1585 bytes_processed_so_far_ += rinfo->target_address_size(); 1586 } 1587 1588 1589 void Serializer::ObjectSerializer::VisitRuntimeEntry(RelocInfo* rinfo) { 1590 int skip = OutputRawData(rinfo->target_address_address(), 1591 kCanReturnSkipInsteadOfSkipping); 1592 HowToCode how_to_code = rinfo->IsCodedSpecially() ? kFromCode : kPlain; 1593 sink_->Put(kExternalReference + how_to_code + kStartOfObject, "ExternalRef"); 1594 sink_->PutInt(skip, "SkipB4ExternalRef"); 1595 Address target = rinfo->target_address(); 1596 sink_->PutInt(serializer_->EncodeExternalReference(target), "reference id"); 1597 bytes_processed_so_far_ += rinfo->target_address_size(); 1598 } 1599 1600 1601 void Serializer::ObjectSerializer::VisitCodeTarget(RelocInfo* rinfo) { 1602 // Out-of-line constant pool entries will be visited by the ConstantPoolArray. 1603 if (FLAG_enable_ool_constant_pool && rinfo->IsInConstantPool()) return; 1604 1605 int skip = OutputRawData(rinfo->target_address_address(), 1606 kCanReturnSkipInsteadOfSkipping); 1607 Code* object = Code::GetCodeFromTargetAddress(rinfo->target_address()); 1608 serializer_->SerializeObject(object, kFromCode, kInnerPointer, skip); 1609 bytes_processed_so_far_ += rinfo->target_address_size(); 1610 } 1611 1612 1613 void Serializer::ObjectSerializer::VisitCodeEntry(Address entry_address) { 1614 int skip = OutputRawData(entry_address, kCanReturnSkipInsteadOfSkipping); 1615 Code* object = Code::cast(Code::GetObjectFromEntryAddress(entry_address)); 1616 serializer_->SerializeObject(object, kPlain, kInnerPointer, skip); 1617 bytes_processed_so_far_ += kPointerSize; 1618 } 1619 1620 1621 void Serializer::ObjectSerializer::VisitCell(RelocInfo* rinfo) { 1622 // Out-of-line constant pool entries will be visited by the ConstantPoolArray. 1623 if (FLAG_enable_ool_constant_pool && rinfo->IsInConstantPool()) return; 1624 1625 int skip = OutputRawData(rinfo->pc(), kCanReturnSkipInsteadOfSkipping); 1626 Cell* object = Cell::cast(rinfo->target_cell()); 1627 serializer_->SerializeObject(object, kPlain, kInnerPointer, skip); 1628 bytes_processed_so_far_ += kPointerSize; 1629 } 1630 1631 1632 void Serializer::ObjectSerializer::VisitExternalOneByteString( 1633 v8::String::ExternalOneByteStringResource** resource_pointer) { 1634 Address references_start = reinterpret_cast<Address>(resource_pointer); 1635 OutputRawData(references_start); 1636 for (int i = 0; i < Natives::GetBuiltinsCount(); i++) { 1637 Object* source = 1638 serializer_->isolate()->heap()->natives_source_cache()->get(i); 1639 if (!source->IsUndefined()) { 1640 ExternalOneByteString* string = ExternalOneByteString::cast(source); 1641 typedef v8::String::ExternalOneByteStringResource Resource; 1642 const Resource* resource = string->resource(); 1643 if (resource == *resource_pointer) { 1644 sink_->Put(kNativesStringResource, "NativesStringResource"); 1645 sink_->PutSection(i, "NativesStringResourceEnd"); 1646 bytes_processed_so_far_ += sizeof(resource); 1647 return; 1648 } 1649 } 1650 } 1651 // One of the strings in the natives cache should match the resource. We 1652 // can't serialize any other kinds of external strings. 1653 UNREACHABLE(); 1654 } 1655 1656 1657 static Code* CloneCodeObject(HeapObject* code) { 1658 Address copy = new byte[code->Size()]; 1659 MemCopy(copy, code->address(), code->Size()); 1660 return Code::cast(HeapObject::FromAddress(copy)); 1661 } 1662 1663 1664 static void WipeOutRelocations(Code* code) { 1665 int mode_mask = 1666 RelocInfo::kCodeTargetMask | 1667 RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) | 1668 RelocInfo::ModeMask(RelocInfo::EXTERNAL_REFERENCE) | 1669 RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY); 1670 for (RelocIterator it(code, mode_mask); !it.done(); it.next()) { 1671 if (!(FLAG_enable_ool_constant_pool && it.rinfo()->IsInConstantPool())) { 1672 it.rinfo()->WipeOut(); 1673 } 1674 } 1675 } 1676 1677 1678 int Serializer::ObjectSerializer::OutputRawData( 1679 Address up_to, Serializer::ObjectSerializer::ReturnSkip return_skip) { 1680 Address object_start = object_->address(); 1681 int base = bytes_processed_so_far_; 1682 int up_to_offset = static_cast<int>(up_to - object_start); 1683 int to_skip = up_to_offset - bytes_processed_so_far_; 1684 int bytes_to_output = to_skip; 1685 bytes_processed_so_far_ += to_skip; 1686 // This assert will fail if the reloc info gives us the target_address_address 1687 // locations in a non-ascending order. Luckily that doesn't happen. 1688 DCHECK(to_skip >= 0); 1689 bool outputting_code = false; 1690 if (to_skip != 0 && code_object_ && !code_has_been_output_) { 1691 // Output the code all at once and fix later. 1692 bytes_to_output = object_->Size() + to_skip - bytes_processed_so_far_; 1693 outputting_code = true; 1694 code_has_been_output_ = true; 1695 } 1696 if (bytes_to_output != 0 && 1697 (!code_object_ || outputting_code)) { 1698 #define RAW_CASE(index) \ 1699 if (!outputting_code && bytes_to_output == index * kPointerSize && \ 1700 index * kPointerSize == to_skip) { \ 1701 sink_->PutSection(kRawData + index, "RawDataFixed"); \ 1702 to_skip = 0; /* This insn already skips. */ \ 1703 } else /* NOLINT */ 1704 COMMON_RAW_LENGTHS(RAW_CASE) 1705 #undef RAW_CASE 1706 { /* NOLINT */ 1707 // We always end up here if we are outputting the code of a code object. 1708 sink_->Put(kRawData, "RawData"); 1709 sink_->PutInt(bytes_to_output, "length"); 1710 } 1711 1712 // To make snapshots reproducible, we need to wipe out all pointers in code. 1713 if (code_object_) { 1714 Code* code = CloneCodeObject(object_); 1715 WipeOutRelocations(code); 1716 // We need to wipe out the header fields *after* wiping out the 1717 // relocations, because some of these fields are needed for the latter. 1718 code->WipeOutHeader(); 1719 object_start = code->address(); 1720 } 1721 1722 const char* description = code_object_ ? "Code" : "Byte"; 1723 for (int i = 0; i < bytes_to_output; i++) { 1724 sink_->PutSection(object_start[base + i], description); 1725 } 1726 if (code_object_) delete[] object_start; 1727 } 1728 if (to_skip != 0 && return_skip == kIgnoringReturn) { 1729 sink_->Put(kSkip, "Skip"); 1730 sink_->PutInt(to_skip, "SkipDistance"); 1731 to_skip = 0; 1732 } 1733 return to_skip; 1734 } 1735 1736 1737 int Serializer::SpaceOfObject(HeapObject* object) { 1738 for (int i = FIRST_SPACE; i <= LAST_SPACE; i++) { 1739 AllocationSpace s = static_cast<AllocationSpace>(i); 1740 if (object->GetHeap()->InSpace(object, s)) { 1741 DCHECK(i < kNumberOfSpaces); 1742 return i; 1743 } 1744 } 1745 UNREACHABLE(); 1746 return 0; 1747 } 1748 1749 1750 int Serializer::Allocate(int space, int size) { 1751 CHECK(space >= 0 && space < kNumberOfSpaces); 1752 int allocation_address = fullness_[space]; 1753 fullness_[space] = allocation_address + size; 1754 return allocation_address; 1755 } 1756 1757 1758 int Serializer::SpaceAreaSize(int space) { 1759 if (space == CODE_SPACE) { 1760 return isolate_->memory_allocator()->CodePageAreaSize(); 1761 } else { 1762 return Page::kPageSize - Page::kObjectStartOffset; 1763 } 1764 } 1765 1766 1767 void Serializer::Pad() { 1768 // The non-branching GetInt will read up to 3 bytes too far, so we need 1769 // to pad the snapshot to make sure we don't read over the end. 1770 for (unsigned i = 0; i < sizeof(int32_t) - 1; i++) { 1771 sink_->Put(kNop, "Padding"); 1772 } 1773 } 1774 1775 1776 void Serializer::InitializeCodeAddressMap() { 1777 isolate_->InitializeLoggingAndCounters(); 1778 code_address_map_ = new CodeAddressMap(isolate_); 1779 } 1780 1781 1782 ScriptData* CodeSerializer::Serialize(Isolate* isolate, 1783 Handle<SharedFunctionInfo> info, 1784 Handle<String> source) { 1785 base::ElapsedTimer timer; 1786 if (FLAG_profile_deserialization) timer.Start(); 1787 1788 // Serialize code object. 1789 List<byte> payload; 1790 ListSnapshotSink list_sink(&payload); 1791 DebugSnapshotSink debug_sink(&list_sink); 1792 SnapshotByteSink* sink = FLAG_trace_code_serializer 1793 ? static_cast<SnapshotByteSink*>(&debug_sink) 1794 : static_cast<SnapshotByteSink*>(&list_sink); 1795 CodeSerializer cs(isolate, sink, *source); 1796 DisallowHeapAllocation no_gc; 1797 Object** location = Handle<Object>::cast(info).location(); 1798 cs.VisitPointer(location); 1799 cs.Pad(); 1800 1801 SerializedCodeData data(&payload, &cs); 1802 ScriptData* script_data = data.GetScriptData(); 1803 1804 if (FLAG_profile_deserialization) { 1805 double ms = timer.Elapsed().InMillisecondsF(); 1806 int length = script_data->length(); 1807 PrintF("[Serializing to %d bytes took %0.3f ms]\n", length, ms); 1808 } 1809 1810 return script_data; 1811 } 1812 1813 1814 void CodeSerializer::SerializeObject(Object* o, HowToCode how_to_code, 1815 WhereToPoint where_to_point, int skip) { 1816 CHECK(o->IsHeapObject()); 1817 HeapObject* heap_object = HeapObject::cast(o); 1818 1819 // The code-caches link to context-specific code objects, which 1820 // the startup and context serializes cannot currently handle. 1821 DCHECK(!heap_object->IsMap() || 1822 Map::cast(heap_object)->code_cache() == 1823 heap_object->GetHeap()->empty_fixed_array()); 1824 1825 int root_index; 1826 if ((root_index = RootIndex(heap_object, how_to_code)) != kInvalidRootIndex) { 1827 PutRoot(root_index, heap_object, how_to_code, where_to_point, skip); 1828 return; 1829 } 1830 1831 // TODO(yangguo) wire up global object. 1832 // TODO(yangguo) We cannot deal with different hash seeds yet. 1833 DCHECK(!heap_object->IsHashTable()); 1834 1835 if (address_mapper_.IsMapped(heap_object)) { 1836 SerializeReferenceToPreviousObject(heap_object, how_to_code, where_to_point, 1837 skip); 1838 return; 1839 } 1840 1841 if (heap_object->IsCode()) { 1842 Code* code_object = Code::cast(heap_object); 1843 if (code_object->kind() == Code::BUILTIN) { 1844 SerializeBuiltin(code_object, how_to_code, where_to_point, skip); 1845 return; 1846 } 1847 if (code_object->IsCodeStubOrIC()) { 1848 SerializeCodeStub(code_object, how_to_code, where_to_point, skip); 1849 return; 1850 } 1851 code_object->ClearInlineCaches(); 1852 } 1853 1854 if (heap_object == source_) { 1855 SerializeSourceObject(how_to_code, where_to_point, skip); 1856 return; 1857 } 1858 1859 SerializeHeapObject(heap_object, how_to_code, where_to_point, skip); 1860 } 1861 1862 1863 void CodeSerializer::SerializeHeapObject(HeapObject* heap_object, 1864 HowToCode how_to_code, 1865 WhereToPoint where_to_point, 1866 int skip) { 1867 if (heap_object->IsScript()) { 1868 // The wrapper cache uses a Foreign object to point to a global handle. 1869 // However, the object visitor expects foreign objects to point to external 1870 // references. Clear the cache to avoid this issue. 1871 Script::cast(heap_object)->ClearWrapperCache(); 1872 } 1873 1874 if (skip != 0) { 1875 sink_->Put(kSkip, "SkipFromSerializeObject"); 1876 sink_->PutInt(skip, "SkipDistanceFromSerializeObject"); 1877 } 1878 1879 if (FLAG_trace_code_serializer) { 1880 PrintF("Encoding heap object: "); 1881 heap_object->ShortPrint(); 1882 PrintF("\n"); 1883 } 1884 1885 // Object has not yet been serialized. Serialize it here. 1886 ObjectSerializer serializer(this, heap_object, sink_, how_to_code, 1887 where_to_point); 1888 serializer.Serialize(); 1889 } 1890 1891 1892 void CodeSerializer::SerializeBuiltin(Code* builtin, HowToCode how_to_code, 1893 WhereToPoint where_to_point, int skip) { 1894 if (skip != 0) { 1895 sink_->Put(kSkip, "SkipFromSerializeBuiltin"); 1896 sink_->PutInt(skip, "SkipDistanceFromSerializeBuiltin"); 1897 } 1898 1899 DCHECK((how_to_code == kPlain && where_to_point == kStartOfObject) || 1900 (how_to_code == kPlain && where_to_point == kInnerPointer) || 1901 (how_to_code == kFromCode && where_to_point == kInnerPointer)); 1902 int builtin_index = builtin->builtin_index(); 1903 DCHECK_LT(builtin_index, Builtins::builtin_count); 1904 DCHECK_LE(0, builtin_index); 1905 1906 if (FLAG_trace_code_serializer) { 1907 PrintF("Encoding builtin: %s\n", 1908 isolate()->builtins()->name(builtin_index)); 1909 } 1910 1911 sink_->Put(kBuiltin + how_to_code + where_to_point, "Builtin"); 1912 sink_->PutInt(builtin_index, "builtin_index"); 1913 } 1914 1915 1916 void CodeSerializer::SerializeCodeStub(Code* code, HowToCode how_to_code, 1917 WhereToPoint where_to_point, int skip) { 1918 DCHECK((how_to_code == kPlain && where_to_point == kStartOfObject) || 1919 (how_to_code == kPlain && where_to_point == kInnerPointer) || 1920 (how_to_code == kFromCode && where_to_point == kInnerPointer)); 1921 uint32_t stub_key = code->stub_key(); 1922 1923 if (stub_key == CodeStub::NoCacheKey()) { 1924 if (FLAG_trace_code_serializer) { 1925 PrintF("Encoding uncacheable code stub as heap object\n"); 1926 } 1927 SerializeHeapObject(code, how_to_code, where_to_point, skip); 1928 return; 1929 } 1930 1931 if (skip != 0) { 1932 sink_->Put(kSkip, "SkipFromSerializeCodeStub"); 1933 sink_->PutInt(skip, "SkipDistanceFromSerializeCodeStub"); 1934 } 1935 1936 int index = AddCodeStubKey(stub_key) + kCodeStubsBaseIndex; 1937 1938 if (FLAG_trace_code_serializer) { 1939 PrintF("Encoding code stub %s as %d\n", 1940 CodeStub::MajorName(CodeStub::MajorKeyFromKey(stub_key), false), 1941 index); 1942 } 1943 1944 sink_->Put(kAttachedReference + how_to_code + where_to_point, "CodeStub"); 1945 sink_->PutInt(index, "CodeStub key"); 1946 } 1947 1948 1949 int CodeSerializer::AddCodeStubKey(uint32_t stub_key) { 1950 // TODO(yangguo) Maybe we need a hash table for a faster lookup than O(n^2). 1951 int index = 0; 1952 while (index < stub_keys_.length()) { 1953 if (stub_keys_[index] == stub_key) return index; 1954 index++; 1955 } 1956 stub_keys_.Add(stub_key); 1957 return index; 1958 } 1959 1960 1961 void CodeSerializer::SerializeSourceObject(HowToCode how_to_code, 1962 WhereToPoint where_to_point, 1963 int skip) { 1964 if (skip != 0) { 1965 sink_->Put(kSkip, "SkipFromSerializeSourceObject"); 1966 sink_->PutInt(skip, "SkipDistanceFromSerializeSourceObject"); 1967 } 1968 1969 if (FLAG_trace_code_serializer) { 1970 PrintF("Encoding source object\n"); 1971 } 1972 1973 DCHECK(how_to_code == kPlain && where_to_point == kStartOfObject); 1974 sink_->Put(kAttachedReference + how_to_code + where_to_point, "Source"); 1975 sink_->PutInt(kSourceObjectIndex, "kSourceObjectIndex"); 1976 } 1977 1978 1979 Handle<SharedFunctionInfo> CodeSerializer::Deserialize(Isolate* isolate, 1980 ScriptData* data, 1981 Handle<String> source) { 1982 base::ElapsedTimer timer; 1983 if (FLAG_profile_deserialization) timer.Start(); 1984 1985 Object* root; 1986 1987 { 1988 HandleScope scope(isolate); 1989 1990 SerializedCodeData scd(data, *source); 1991 SnapshotByteSource payload(scd.Payload(), scd.PayloadLength()); 1992 Deserializer deserializer(&payload); 1993 STATIC_ASSERT(NEW_SPACE == 0); 1994 for (int i = NEW_SPACE; i <= PROPERTY_CELL_SPACE; i++) { 1995 deserializer.set_reservation(i, scd.GetReservation(i)); 1996 } 1997 1998 // Prepare and register list of attached objects. 1999 Vector<const uint32_t> code_stub_keys = scd.CodeStubKeys(); 2000 Vector<Handle<Object> > attached_objects = Vector<Handle<Object> >::New( 2001 code_stub_keys.length() + kCodeStubsBaseIndex); 2002 attached_objects[kSourceObjectIndex] = source; 2003 for (int i = 0; i < code_stub_keys.length(); i++) { 2004 attached_objects[i + kCodeStubsBaseIndex] = 2005 CodeStub::GetCode(isolate, code_stub_keys[i]).ToHandleChecked(); 2006 } 2007 deserializer.SetAttachedObjects(&attached_objects); 2008 2009 // Deserialize. 2010 deserializer.DeserializePartial(isolate, &root); 2011 deserializer.FlushICacheForNewCodeObjects(); 2012 } 2013 2014 if (FLAG_profile_deserialization) { 2015 double ms = timer.Elapsed().InMillisecondsF(); 2016 int length = data->length(); 2017 PrintF("[Deserializing from %d bytes took %0.3f ms]\n", length, ms); 2018 } 2019 return Handle<SharedFunctionInfo>(SharedFunctionInfo::cast(root), isolate); 2020 } 2021 2022 2023 SerializedCodeData::SerializedCodeData(List<byte>* payload, CodeSerializer* cs) 2024 : owns_script_data_(true) { 2025 DisallowHeapAllocation no_gc; 2026 List<uint32_t>* stub_keys = cs->stub_keys(); 2027 2028 // Calculate sizes. 2029 int num_stub_keys = stub_keys->length(); 2030 int stub_keys_size = stub_keys->length() * kInt32Size; 2031 int data_length = kHeaderSize + stub_keys_size + payload->length(); 2032 2033 // Allocate backing store and create result data. 2034 byte* data = NewArray<byte>(data_length); 2035 DCHECK(IsAligned(reinterpret_cast<intptr_t>(data), kPointerAlignment)); 2036 script_data_ = new ScriptData(data, data_length); 2037 script_data_->AcquireDataOwnership(); 2038 2039 // Set header values. 2040 SetHeaderValue(kCheckSumOffset, CheckSum(cs->source())); 2041 SetHeaderValue(kNumCodeStubKeysOffset, num_stub_keys); 2042 SetHeaderValue(kPayloadLengthOffset, payload->length()); 2043 STATIC_ASSERT(NEW_SPACE == 0); 2044 for (int i = NEW_SPACE; i <= PROPERTY_CELL_SPACE; i++) { 2045 SetHeaderValue(kReservationsOffset + i, cs->CurrentAllocationAddress(i)); 2046 } 2047 2048 // Copy code stub keys. 2049 CopyBytes(data + kHeaderSize, reinterpret_cast<byte*>(stub_keys->begin()), 2050 stub_keys_size); 2051 2052 // Copy serialized data. 2053 CopyBytes(data + kHeaderSize + stub_keys_size, payload->begin(), 2054 static_cast<size_t>(payload->length())); 2055 } 2056 2057 2058 bool SerializedCodeData::IsSane(String* source) { 2059 return GetHeaderValue(kCheckSumOffset) == CheckSum(source) && 2060 PayloadLength() >= SharedFunctionInfo::kSize; 2061 } 2062 2063 2064 int SerializedCodeData::CheckSum(String* string) { 2065 int checksum = Version::Hash(); 2066 #ifdef DEBUG 2067 uint32_t seed = static_cast<uint32_t>(checksum); 2068 checksum = static_cast<int>(IteratingStringHasher::Hash(string, seed)); 2069 #endif // DEBUG 2070 return checksum; 2071 } 2072 } } // namespace v8::internal 2073
