// Copyright 2012 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #include "src/v8.h" #include "src/accessors.h" #include "src/api.h" #include "src/base/platform/platform.h" #include "src/bootstrapper.h" #include "src/code-stubs.h" #include "src/deoptimizer.h" #include "src/execution.h" #include "src/global-handles.h" #include "src/ic/ic.h" #include "src/ic/stub-cache.h" #include "src/natives.h" #include "src/objects.h" #include "src/runtime.h" #include "src/serialize.h" #include "src/snapshot.h" #include "src/snapshot-source-sink.h" #include "src/v8threads.h" #include "src/version.h" namespace v8 { namespace internal { // ----------------------------------------------------------------------------- // Coding of external references. // The encoding of an external reference. The type is in the high word. // The id is in the low word. static uint32_t EncodeExternal(TypeCode type, uint16_t id) { return static_cast<uint32_t>(type) << 16 | id; } static int* GetInternalPointer(StatsCounter* counter) { // All counters refer to dummy_counter, if deserializing happens without // setting up counters. static int dummy_counter = 0; return counter->Enabled() ? counter->GetInternalPointer() : &dummy_counter; } ExternalReferenceTable* ExternalReferenceTable::instance(Isolate* isolate) { ExternalReferenceTable* external_reference_table = isolate->external_reference_table(); if (external_reference_table == NULL) { external_reference_table = new ExternalReferenceTable(isolate); isolate->set_external_reference_table(external_reference_table); } return external_reference_table; } void ExternalReferenceTable::AddFromId(TypeCode type, uint16_t id, const char* name, Isolate* isolate) { Address address; switch (type) { case C_BUILTIN: { ExternalReference ref(static_cast<Builtins::CFunctionId>(id), isolate); address = ref.address(); break; } case BUILTIN: { ExternalReference ref(static_cast<Builtins::Name>(id), isolate); address = ref.address(); break; } case RUNTIME_FUNCTION: { ExternalReference ref(static_cast<Runtime::FunctionId>(id), isolate); address = ref.address(); break; } case IC_UTILITY: { ExternalReference ref(IC_Utility(static_cast<IC::UtilityId>(id)), isolate); address = ref.address(); break; } default: UNREACHABLE(); return; } Add(address, type, id, name); } void ExternalReferenceTable::Add(Address address, TypeCode type, uint16_t id, const char* name) { DCHECK_NE(NULL, address); ExternalReferenceEntry entry; entry.address = address; entry.code = EncodeExternal(type, id); entry.name = name; DCHECK_NE(0, entry.code); // Assert that the code is added in ascending order to rule out duplicates. DCHECK((size() == 0) || (code(size() - 1) < entry.code)); refs_.Add(entry); if (id > max_id_[type]) max_id_[type] = id; } void ExternalReferenceTable::PopulateTable(Isolate* isolate) { for (int type_code = 0; type_code < kTypeCodeCount; type_code++) { max_id_[type_code] = 0; } // Miscellaneous Add(ExternalReference::roots_array_start(isolate).address(), "Heap::roots_array_start()"); Add(ExternalReference::address_of_stack_limit(isolate).address(), "StackGuard::address_of_jslimit()"); Add(ExternalReference::address_of_real_stack_limit(isolate).address(), "StackGuard::address_of_real_jslimit()"); Add(ExternalReference::new_space_start(isolate).address(), "Heap::NewSpaceStart()"); Add(ExternalReference::new_space_mask(isolate).address(), "Heap::NewSpaceMask()"); Add(ExternalReference::new_space_allocation_limit_address(isolate).address(), "Heap::NewSpaceAllocationLimitAddress()"); Add(ExternalReference::new_space_allocation_top_address(isolate).address(), "Heap::NewSpaceAllocationTopAddress()"); Add(ExternalReference::debug_break(isolate).address(), "Debug::Break()"); Add(ExternalReference::debug_step_in_fp_address(isolate).address(), "Debug::step_in_fp_addr()"); Add(ExternalReference::mod_two_doubles_operation(isolate).address(), "mod_two_doubles"); // Keyed lookup cache. Add(ExternalReference::keyed_lookup_cache_keys(isolate).address(), "KeyedLookupCache::keys()"); Add(ExternalReference::keyed_lookup_cache_field_offsets(isolate).address(), "KeyedLookupCache::field_offsets()"); Add(ExternalReference::handle_scope_next_address(isolate).address(), "HandleScope::next"); Add(ExternalReference::handle_scope_limit_address(isolate).address(), "HandleScope::limit"); Add(ExternalReference::handle_scope_level_address(isolate).address(), "HandleScope::level"); Add(ExternalReference::new_deoptimizer_function(isolate).address(), "Deoptimizer::New()"); Add(ExternalReference::compute_output_frames_function(isolate).address(), "Deoptimizer::ComputeOutputFrames()"); Add(ExternalReference::address_of_min_int().address(), "LDoubleConstant::min_int"); Add(ExternalReference::address_of_one_half().address(), "LDoubleConstant::one_half"); Add(ExternalReference::isolate_address(isolate).address(), "isolate"); Add(ExternalReference::address_of_negative_infinity().address(), "LDoubleConstant::negative_infinity"); Add(ExternalReference::power_double_double_function(isolate).address(), "power_double_double_function"); Add(ExternalReference::power_double_int_function(isolate).address(), "power_double_int_function"); Add(ExternalReference::math_log_double_function(isolate).address(), "std::log"); Add(ExternalReference::store_buffer_top(isolate).address(), "store_buffer_top"); Add(ExternalReference::address_of_canonical_non_hole_nan().address(), "canonical_nan"); Add(ExternalReference::address_of_the_hole_nan().address(), "the_hole_nan"); Add(ExternalReference::get_date_field_function(isolate).address(), "JSDate::GetField"); Add(ExternalReference::date_cache_stamp(isolate).address(), "date_cache_stamp"); Add(ExternalReference::address_of_pending_message_obj(isolate).address(), "address_of_pending_message_obj"); Add(ExternalReference::address_of_has_pending_message(isolate).address(), "address_of_has_pending_message"); Add(ExternalReference::address_of_pending_message_script(isolate).address(), "pending_message_script"); Add(ExternalReference::get_make_code_young_function(isolate).address(), "Code::MakeCodeYoung"); Add(ExternalReference::cpu_features().address(), "cpu_features"); Add(ExternalReference(Runtime::kAllocateInNewSpace, isolate).address(), "Runtime::AllocateInNewSpace"); Add(ExternalReference(Runtime::kAllocateInTargetSpace, isolate).address(), "Runtime::AllocateInTargetSpace"); Add(ExternalReference::old_pointer_space_allocation_top_address(isolate) .address(), "Heap::OldPointerSpaceAllocationTopAddress"); Add(ExternalReference::old_pointer_space_allocation_limit_address(isolate) .address(), "Heap::OldPointerSpaceAllocationLimitAddress"); Add(ExternalReference::old_data_space_allocation_top_address(isolate) .address(), "Heap::OldDataSpaceAllocationTopAddress"); Add(ExternalReference::old_data_space_allocation_limit_address(isolate) .address(), "Heap::OldDataSpaceAllocationLimitAddress"); Add(ExternalReference::allocation_sites_list_address(isolate).address(), "Heap::allocation_sites_list_address()"); Add(ExternalReference::address_of_uint32_bias().address(), "uint32_bias"); Add(ExternalReference::get_mark_code_as_executed_function(isolate).address(), "Code::MarkCodeAsExecuted"); Add(ExternalReference::is_profiling_address(isolate).address(), "CpuProfiler::is_profiling"); Add(ExternalReference::scheduled_exception_address(isolate).address(), "Isolate::scheduled_exception"); Add(ExternalReference::invoke_function_callback(isolate).address(), "InvokeFunctionCallback"); Add(ExternalReference::invoke_accessor_getter_callback(isolate).address(), "InvokeAccessorGetterCallback"); Add(ExternalReference::flush_icache_function(isolate).address(), "CpuFeatures::FlushICache"); Add(ExternalReference::log_enter_external_function(isolate).address(), "Logger::EnterExternal"); Add(ExternalReference::log_leave_external_function(isolate).address(), "Logger::LeaveExternal"); Add(ExternalReference::address_of_minus_one_half().address(), "double_constants.minus_one_half"); Add(ExternalReference::stress_deopt_count(isolate).address(), "Isolate::stress_deopt_count_address()"); Add(ExternalReference::incremental_marking_record_write_function(isolate) .address(), "IncrementalMarking::RecordWriteFromCode"); // Debug addresses Add(ExternalReference::debug_after_break_target_address(isolate).address(), "Debug::after_break_target_address()"); Add(ExternalReference::debug_restarter_frame_function_pointer_address(isolate) .address(), "Debug::restarter_frame_function_pointer_address()"); Add(ExternalReference::debug_is_active_address(isolate).address(), "Debug::is_active_address()"); #ifndef V8_INTERPRETED_REGEXP Add(ExternalReference::re_case_insensitive_compare_uc16(isolate).address(), "NativeRegExpMacroAssembler::CaseInsensitiveCompareUC16()"); Add(ExternalReference::re_check_stack_guard_state(isolate).address(), "RegExpMacroAssembler*::CheckStackGuardState()"); Add(ExternalReference::re_grow_stack(isolate).address(), "NativeRegExpMacroAssembler::GrowStack()"); Add(ExternalReference::re_word_character_map().address(), "NativeRegExpMacroAssembler::word_character_map"); Add(ExternalReference::address_of_regexp_stack_limit(isolate).address(), "RegExpStack::limit_address()"); Add(ExternalReference::address_of_regexp_stack_memory_address(isolate) .address(), "RegExpStack::memory_address()"); Add(ExternalReference::address_of_regexp_stack_memory_size(isolate).address(), "RegExpStack::memory_size()"); Add(ExternalReference::address_of_static_offsets_vector(isolate).address(), "OffsetsVector::static_offsets_vector"); #endif // V8_INTERPRETED_REGEXP // The following populates all of the different type of external references // into the ExternalReferenceTable. // // NOTE: This function was originally 100k of code. It has since been // rewritten to be mostly table driven, as the callback macro style tends to // very easily cause code bloat. Please be careful in the future when adding // new references. struct RefTableEntry { TypeCode type; uint16_t id; const char* name; }; static const RefTableEntry ref_table[] = { // Builtins #define DEF_ENTRY_C(name, ignored) \ { C_BUILTIN, \ Builtins::c_##name, \ "Builtins::" #name }, BUILTIN_LIST_C(DEF_ENTRY_C) #undef DEF_ENTRY_C #define DEF_ENTRY_C(name, ignored) \ { BUILTIN, \ Builtins::k##name, \ "Builtins::" #name }, #define DEF_ENTRY_A(name, kind, state, extra) DEF_ENTRY_C(name, ignored) BUILTIN_LIST_C(DEF_ENTRY_C) BUILTIN_LIST_A(DEF_ENTRY_A) BUILTIN_LIST_DEBUG_A(DEF_ENTRY_A) #undef DEF_ENTRY_C #undef DEF_ENTRY_A // Runtime functions #define RUNTIME_ENTRY(name, nargs, ressize) \ { RUNTIME_FUNCTION, \ Runtime::k##name, \ "Runtime::" #name }, RUNTIME_FUNCTION_LIST(RUNTIME_ENTRY) INLINE_OPTIMIZED_FUNCTION_LIST(RUNTIME_ENTRY) #undef RUNTIME_ENTRY #define INLINE_OPTIMIZED_ENTRY(name, nargs, ressize) \ { RUNTIME_FUNCTION, \ Runtime::kInlineOptimized##name, \ "Runtime::" #name }, INLINE_OPTIMIZED_FUNCTION_LIST(INLINE_OPTIMIZED_ENTRY) #undef INLINE_OPTIMIZED_ENTRY // IC utilities #define IC_ENTRY(name) \ { IC_UTILITY, \ IC::k##name, \ "IC::" #name }, IC_UTIL_LIST(IC_ENTRY) #undef IC_ENTRY }; // end of ref_table[]. for (size_t i = 0; i < arraysize(ref_table); ++i) { AddFromId(ref_table[i].type, ref_table[i].id, ref_table[i].name, isolate); } // Stat counters struct StatsRefTableEntry { StatsCounter* (Counters::*counter)(); uint16_t id; const char* name; }; const StatsRefTableEntry stats_ref_table[] = { #define COUNTER_ENTRY(name, caption) \ { &Counters::name, \ Counters::k_##name, \ "Counters::" #name }, STATS_COUNTER_LIST_1(COUNTER_ENTRY) STATS_COUNTER_LIST_2(COUNTER_ENTRY) #undef COUNTER_ENTRY }; // end of stats_ref_table[]. Counters* counters = isolate->counters(); for (size_t i = 0; i < arraysize(stats_ref_table); ++i) { Add(reinterpret_cast<Address>(GetInternalPointer( (counters->*(stats_ref_table[i].counter))())), STATS_COUNTER, stats_ref_table[i].id, stats_ref_table[i].name); } // Top addresses const char* AddressNames[] = { #define BUILD_NAME_LITERAL(CamelName, hacker_name) \ "Isolate::" #hacker_name "_address", FOR_EACH_ISOLATE_ADDRESS_NAME(BUILD_NAME_LITERAL) NULL #undef BUILD_NAME_LITERAL }; for (uint16_t i = 0; i < Isolate::kIsolateAddressCount; ++i) { Add(isolate->get_address_from_id((Isolate::AddressId)i), TOP_ADDRESS, i, AddressNames[i]); } // Accessors #define ACCESSOR_INFO_DECLARATION(name) \ Add(FUNCTION_ADDR(&Accessors::name##Getter), \ ACCESSOR, \ Accessors::k##name##Getter, \ "Accessors::" #name "Getter"); \ Add(FUNCTION_ADDR(&Accessors::name##Setter), \ ACCESSOR, \ Accessors::k##name##Setter, \ "Accessors::" #name "Setter"); ACCESSOR_INFO_LIST(ACCESSOR_INFO_DECLARATION) #undef ACCESSOR_INFO_DECLARATION StubCache* stub_cache = isolate->stub_cache(); // Stub cache tables Add(stub_cache->key_reference(StubCache::kPrimary).address(), STUB_CACHE_TABLE, 1, "StubCache::primary_->key"); Add(stub_cache->value_reference(StubCache::kPrimary).address(), STUB_CACHE_TABLE, 2, "StubCache::primary_->value"); Add(stub_cache->map_reference(StubCache::kPrimary).address(), STUB_CACHE_TABLE, 3, "StubCache::primary_->map"); Add(stub_cache->key_reference(StubCache::kSecondary).address(), STUB_CACHE_TABLE, 4, "StubCache::secondary_->key"); Add(stub_cache->value_reference(StubCache::kSecondary).address(), STUB_CACHE_TABLE, 5, "StubCache::secondary_->value"); Add(stub_cache->map_reference(StubCache::kSecondary).address(), STUB_CACHE_TABLE, 6, "StubCache::secondary_->map"); // Runtime entries Add(ExternalReference::delete_handle_scope_extensions(isolate).address(), RUNTIME_ENTRY, 1, "HandleScope::DeleteExtensions"); Add(ExternalReference::incremental_marking_record_write_function(isolate) .address(), RUNTIME_ENTRY, 2, "IncrementalMarking::RecordWrite"); Add(ExternalReference::store_buffer_overflow_function(isolate).address(), RUNTIME_ENTRY, 3, "StoreBuffer::StoreBufferOverflow"); // Add a small set of deopt entry addresses to encoder without generating the // deopt table code, which isn't possible at deserialization time. HandleScope scope(isolate); for (int entry = 0; entry < kDeoptTableSerializeEntryCount; ++entry) { Address address = Deoptimizer::GetDeoptimizationEntry( isolate, entry, Deoptimizer::LAZY, Deoptimizer::CALCULATE_ENTRY_ADDRESS); Add(address, LAZY_DEOPTIMIZATION, entry, "lazy_deopt"); } } ExternalReferenceEncoder::ExternalReferenceEncoder(Isolate* isolate) : encodings_(HashMap::PointersMatch), isolate_(isolate) { ExternalReferenceTable* external_references = ExternalReferenceTable::instance(isolate_); for (int i = 0; i < external_references->size(); ++i) { Put(external_references->address(i), i); } } uint32_t ExternalReferenceEncoder::Encode(Address key) const { int index = IndexOf(key); DCHECK(key == NULL || index >= 0); return index >= 0 ? ExternalReferenceTable::instance(isolate_)->code(index) : 0; } const char* ExternalReferenceEncoder::NameOfAddress(Address key) const { int index = IndexOf(key); return index >= 0 ? ExternalReferenceTable::instance(isolate_)->name(index) : "<unknown>"; } int ExternalReferenceEncoder::IndexOf(Address key) const { if (key == NULL) return -1; HashMap::Entry* entry = const_cast<HashMap&>(encodings_).Lookup(key, Hash(key), false); return entry == NULL ? -1 : static_cast<int>(reinterpret_cast<intptr_t>(entry->value)); } void ExternalReferenceEncoder::Put(Address key, int index) { HashMap::Entry* entry = encodings_.Lookup(key, Hash(key), true); entry->value = reinterpret_cast<void*>(index); } ExternalReferenceDecoder::ExternalReferenceDecoder(Isolate* isolate) : encodings_(NewArray<Address*>(kTypeCodeCount)), isolate_(isolate) { ExternalReferenceTable* external_references = ExternalReferenceTable::instance(isolate_); for (int type = kFirstTypeCode; type < kTypeCodeCount; ++type) { int max = external_references->max_id(type) + 1; encodings_[type] = NewArray<Address>(max + 1); } for (int i = 0; i < external_references->size(); ++i) { Put(external_references->code(i), external_references->address(i)); } } ExternalReferenceDecoder::~ExternalReferenceDecoder() { for (int type = kFirstTypeCode; type < kTypeCodeCount; ++type) { DeleteArray(encodings_[type]); } DeleteArray(encodings_); } class CodeAddressMap: public CodeEventLogger { public: explicit CodeAddressMap(Isolate* isolate) : isolate_(isolate) { isolate->logger()->addCodeEventListener(this); } virtual ~CodeAddressMap() { isolate_->logger()->removeCodeEventListener(this); } virtual void CodeMoveEvent(Address from, Address to) { address_to_name_map_.Move(from, to); } virtual void CodeDisableOptEvent(Code* code, SharedFunctionInfo* shared) { } virtual void CodeDeleteEvent(Address from) { address_to_name_map_.Remove(from); } const char* Lookup(Address address) { return address_to_name_map_.Lookup(address); } private: class NameMap { public: NameMap() : impl_(HashMap::PointersMatch) {} ~NameMap() { for (HashMap::Entry* p = impl_.Start(); p != NULL; p = impl_.Next(p)) { DeleteArray(static_cast<const char*>(p->value)); } } void Insert(Address code_address, const char* name, int name_size) { HashMap::Entry* entry = FindOrCreateEntry(code_address); if (entry->value == NULL) { entry->value = CopyName(name, name_size); } } const char* Lookup(Address code_address) { HashMap::Entry* entry = FindEntry(code_address); return (entry != NULL) ? static_cast<const char*>(entry->value) : NULL; } void Remove(Address code_address) { HashMap::Entry* entry = FindEntry(code_address); if (entry != NULL) { DeleteArray(static_cast<char*>(entry->value)); RemoveEntry(entry); } } void Move(Address from, Address to) { if (from == to) return; HashMap::Entry* from_entry = FindEntry(from); DCHECK(from_entry != NULL); void* value = from_entry->value; RemoveEntry(from_entry); HashMap::Entry* to_entry = FindOrCreateEntry(to); DCHECK(to_entry->value == NULL); to_entry->value = value; } private: static char* CopyName(const char* name, int name_size) { char* result = NewArray<char>(name_size + 1); for (int i = 0; i < name_size; ++i) { char c = name[i]; if (c == '\0') c = ' '; result[i] = c; } result[name_size] = '\0'; return result; } HashMap::Entry* FindOrCreateEntry(Address code_address) { return impl_.Lookup(code_address, ComputePointerHash(code_address), true); } HashMap::Entry* FindEntry(Address code_address) { return impl_.Lookup(code_address, ComputePointerHash(code_address), false); } void RemoveEntry(HashMap::Entry* entry) { impl_.Remove(entry->key, entry->hash); } HashMap impl_; DISALLOW_COPY_AND_ASSIGN(NameMap); }; virtual void LogRecordedBuffer(Code* code, SharedFunctionInfo*, const char* name, int length) { address_to_name_map_.Insert(code->address(), name, length); } NameMap address_to_name_map_; Isolate* isolate_; }; Deserializer::Deserializer(SnapshotByteSource* source) : isolate_(NULL), attached_objects_(NULL), source_(source), external_reference_decoder_(NULL) { for (int i = 0; i < LAST_SPACE + 1; i++) { reservations_[i] = kUninitializedReservation; } } void Deserializer::FlushICacheForNewCodeObjects() { PageIterator it(isolate_->heap()->code_space()); while (it.has_next()) { Page* p = it.next(); CpuFeatures::FlushICache(p->area_start(), p->area_end() - p->area_start()); } } void Deserializer::Deserialize(Isolate* isolate) { isolate_ = isolate; DCHECK(isolate_ != NULL); isolate_->heap()->ReserveSpace(reservations_, &high_water_[0]); // No active threads. DCHECK_EQ(NULL, isolate_->thread_manager()->FirstThreadStateInUse()); // No active handles. DCHECK(isolate_->handle_scope_implementer()->blocks()->is_empty()); DCHECK_EQ(NULL, external_reference_decoder_); external_reference_decoder_ = new ExternalReferenceDecoder(isolate); isolate_->heap()->IterateSmiRoots(this); isolate_->heap()->IterateStrongRoots(this, VISIT_ONLY_STRONG); isolate_->heap()->RepairFreeListsAfterBoot(); isolate_->heap()->IterateWeakRoots(this, VISIT_ALL); isolate_->heap()->set_native_contexts_list( isolate_->heap()->undefined_value()); isolate_->heap()->set_array_buffers_list( isolate_->heap()->undefined_value()); // The allocation site list is build during root iteration, but if no sites // were encountered then it needs to be initialized to undefined. if (isolate_->heap()->allocation_sites_list() == Smi::FromInt(0)) { isolate_->heap()->set_allocation_sites_list( isolate_->heap()->undefined_value()); } isolate_->heap()->InitializeWeakObjectToCodeTable(); // Update data pointers to the external strings containing natives sources. for (int i = 0; i < Natives::GetBuiltinsCount(); i++) { Object* source = isolate_->heap()->natives_source_cache()->get(i); if (!source->IsUndefined()) { ExternalOneByteString::cast(source)->update_data_cache(); } } FlushICacheForNewCodeObjects(); // Issue code events for newly deserialized code objects. LOG_CODE_EVENT(isolate_, LogCodeObjects()); LOG_CODE_EVENT(isolate_, LogCompiledFunctions()); } void Deserializer::DeserializePartial(Isolate* isolate, Object** root) { isolate_ = isolate; for (int i = NEW_SPACE; i < kNumberOfSpaces; i++) { DCHECK(reservations_[i] != kUninitializedReservation); } isolate_->heap()->ReserveSpace(reservations_, &high_water_[0]); if (external_reference_decoder_ == NULL) { external_reference_decoder_ = new ExternalReferenceDecoder(isolate); } DisallowHeapAllocation no_gc; // Keep track of the code space start and end pointers in case new // code objects were unserialized OldSpace* code_space = isolate_->heap()->code_space(); Address start_address = code_space->top(); VisitPointer(root); // There's no code deserialized here. If this assert fires // then that's changed and logging should be added to notify // the profiler et al of the new code. CHECK_EQ(start_address, code_space->top()); } Deserializer::~Deserializer() { // TODO(svenpanne) Re-enable this assertion when v8 initialization is fixed. // DCHECK(source_->AtEOF()); if (external_reference_decoder_) { delete external_reference_decoder_; external_reference_decoder_ = NULL; } if (attached_objects_) attached_objects_->Dispose(); } // This is called on the roots. It is the driver of the deserialization // process. It is also called on the body of each function. void Deserializer::VisitPointers(Object** start, Object** end) { // The space must be new space. Any other space would cause ReadChunk to try // to update the remembered using NULL as the address. ReadChunk(start, end, NEW_SPACE, NULL); } void Deserializer::RelinkAllocationSite(AllocationSite* site) { if (isolate_->heap()->allocation_sites_list() == Smi::FromInt(0)) { site->set_weak_next(isolate_->heap()->undefined_value()); } else { site->set_weak_next(isolate_->heap()->allocation_sites_list()); } isolate_->heap()->set_allocation_sites_list(site); } // Used to insert a deserialized internalized string into the string table. class StringTableInsertionKey : public HashTableKey { public: explicit StringTableInsertionKey(String* string) : string_(string), hash_(HashForObject(string)) { DCHECK(string->IsInternalizedString()); } virtual bool IsMatch(Object* string) { // We know that all entries in a hash table had their hash keys created. // Use that knowledge to have fast failure. if (hash_ != HashForObject(string)) return false; // We want to compare the content of two internalized strings here. return string_->SlowEquals(String::cast(string)); } virtual uint32_t Hash() OVERRIDE { return hash_; } virtual uint32_t HashForObject(Object* key) OVERRIDE { return String::cast(key)->Hash(); } MUST_USE_RESULT virtual Handle<Object> AsHandle(Isolate* isolate) OVERRIDE { return handle(string_, isolate); } String* string_; uint32_t hash_; }; HeapObject* Deserializer::ProcessNewObjectFromSerializedCode(HeapObject* obj) { if (obj->IsString()) { String* string = String::cast(obj); // Uninitialize hash field as the hash seed may have changed. string->set_hash_field(String::kEmptyHashField); if (string->IsInternalizedString()) { DisallowHeapAllocation no_gc; HandleScope scope(isolate_); StringTableInsertionKey key(string); String* canonical = *StringTable::LookupKey(isolate_, &key); string->SetForwardedInternalizedString(canonical); return canonical; } } return obj; } Object* Deserializer::ProcessBackRefInSerializedCode(Object* obj) { if (obj->IsInternalizedString()) { return String::cast(obj)->GetForwardedInternalizedString(); } return obj; } // This routine writes the new object into the pointer provided and then // returns true if the new object was in young space and false otherwise. // The reason for this strange interface is that otherwise the object is // written very late, which means the FreeSpace map is not set up by the // time we need to use it to mark the space at the end of a page free. void Deserializer::ReadObject(int space_number, Object** write_back) { int size = source_->GetInt() << kObjectAlignmentBits; Address address = Allocate(space_number, size); HeapObject* obj = HeapObject::FromAddress(address); isolate_->heap()->OnAllocationEvent(obj, size); Object** current = reinterpret_cast<Object**>(address); Object** limit = current + (size >> kPointerSizeLog2); if (FLAG_log_snapshot_positions) { LOG(isolate_, SnapshotPositionEvent(address, source_->position())); } ReadChunk(current, limit, space_number, address); // TODO(mvstanton): consider treating the heap()->allocation_sites_list() // as a (weak) root. If this root is relocated correctly, // RelinkAllocationSite() isn't necessary. if (obj->IsAllocationSite()) RelinkAllocationSite(AllocationSite::cast(obj)); // Fix up strings from serialized user code. if (deserializing_user_code()) obj = ProcessNewObjectFromSerializedCode(obj); *write_back = obj; #ifdef DEBUG bool is_codespace = (space_number == CODE_SPACE); DCHECK(obj->IsCode() == is_codespace); #endif } void Deserializer::ReadChunk(Object** current, Object** limit, int source_space, Address current_object_address) { Isolate* const isolate = isolate_; // Write barrier support costs around 1% in startup time. In fact there // are no new space objects in current boot snapshots, so it's not needed, // but that may change. bool write_barrier_needed = (current_object_address != NULL && source_space != NEW_SPACE && source_space != CELL_SPACE && source_space != PROPERTY_CELL_SPACE && source_space != CODE_SPACE && source_space != OLD_DATA_SPACE); while (current < limit) { int data = source_->Get(); switch (data) { #define CASE_STATEMENT(where, how, within, space_number) \ case where + how + within + space_number: \ STATIC_ASSERT((where & ~kPointedToMask) == 0); \ STATIC_ASSERT((how & ~kHowToCodeMask) == 0); \ STATIC_ASSERT((within & ~kWhereToPointMask) == 0); \ STATIC_ASSERT((space_number & ~kSpaceMask) == 0); #define CASE_BODY(where, how, within, space_number_if_any) \ { \ bool emit_write_barrier = false; \ bool current_was_incremented = false; \ int space_number = space_number_if_any == kAnyOldSpace \ ? (data & kSpaceMask) \ : space_number_if_any; \ if (where == kNewObject && how == kPlain && within == kStartOfObject) { \ ReadObject(space_number, current); \ emit_write_barrier = (space_number == NEW_SPACE); \ } else { \ Object* new_object = NULL; /* May not be a real Object pointer. */ \ if (where == kNewObject) { \ ReadObject(space_number, &new_object); \ } else if (where == kRootArray) { \ int root_id = source_->GetInt(); \ new_object = isolate->heap()->roots_array_start()[root_id]; \ emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ } else if (where == kPartialSnapshotCache) { \ int cache_index = source_->GetInt(); \ new_object = isolate->serialize_partial_snapshot_cache()[cache_index]; \ emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ } else if (where == kExternalReference) { \ int skip = source_->GetInt(); \ current = reinterpret_cast<Object**>( \ reinterpret_cast<Address>(current) + skip); \ int reference_id = source_->GetInt(); \ Address address = external_reference_decoder_->Decode(reference_id); \ new_object = reinterpret_cast<Object*>(address); \ } else if (where == kBackref) { \ emit_write_barrier = (space_number == NEW_SPACE); \ new_object = GetAddressFromEnd(data & kSpaceMask); \ if (deserializing_user_code()) { \ new_object = ProcessBackRefInSerializedCode(new_object); \ } \ } else if (where == kBuiltin) { \ DCHECK(deserializing_user_code()); \ int builtin_id = source_->GetInt(); \ DCHECK_LE(0, builtin_id); \ DCHECK_LT(builtin_id, Builtins::builtin_count); \ Builtins::Name name = static_cast<Builtins::Name>(builtin_id); \ new_object = isolate->builtins()->builtin(name); \ emit_write_barrier = false; \ } else if (where == kAttachedReference) { \ DCHECK(deserializing_user_code()); \ int index = source_->GetInt(); \ new_object = *attached_objects_->at(index); \ emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ } else { \ DCHECK(where == kBackrefWithSkip); \ int skip = source_->GetInt(); \ current = reinterpret_cast<Object**>( \ reinterpret_cast<Address>(current) + skip); \ emit_write_barrier = (space_number == NEW_SPACE); \ new_object = GetAddressFromEnd(data & kSpaceMask); \ if (deserializing_user_code()) { \ new_object = ProcessBackRefInSerializedCode(new_object); \ } \ } \ if (within == kInnerPointer) { \ if (space_number != CODE_SPACE || new_object->IsCode()) { \ Code* new_code_object = reinterpret_cast<Code*>(new_object); \ new_object = \ reinterpret_cast<Object*>(new_code_object->instruction_start()); \ } else { \ DCHECK(space_number == CODE_SPACE); \ Cell* cell = Cell::cast(new_object); \ new_object = reinterpret_cast<Object*>(cell->ValueAddress()); \ } \ } \ if (how == kFromCode) { \ Address location_of_branch_data = reinterpret_cast<Address>(current); \ Assembler::deserialization_set_special_target_at( \ location_of_branch_data, \ Code::cast(HeapObject::FromAddress(current_object_address)), \ reinterpret_cast<Address>(new_object)); \ location_of_branch_data += Assembler::kSpecialTargetSize; \ current = reinterpret_cast<Object**>(location_of_branch_data); \ current_was_incremented = true; \ } else { \ *current = new_object; \ } \ } \ if (emit_write_barrier && write_barrier_needed) { \ Address current_address = reinterpret_cast<Address>(current); \ isolate->heap()->RecordWrite( \ current_object_address, \ static_cast<int>(current_address - current_object_address)); \ } \ if (!current_was_incremented) { \ current++; \ } \ break; \ } // This generates a case and a body for the new space (which has to do extra // write barrier handling) and handles the other spaces with 8 fall-through // cases and one body. #define ALL_SPACES(where, how, within) \ CASE_STATEMENT(where, how, within, NEW_SPACE) \ CASE_BODY(where, how, within, NEW_SPACE) \ CASE_STATEMENT(where, how, within, OLD_DATA_SPACE) \ CASE_STATEMENT(where, how, within, OLD_POINTER_SPACE) \ CASE_STATEMENT(where, how, within, CODE_SPACE) \ CASE_STATEMENT(where, how, within, CELL_SPACE) \ CASE_STATEMENT(where, how, within, PROPERTY_CELL_SPACE) \ CASE_STATEMENT(where, how, within, MAP_SPACE) \ CASE_BODY(where, how, within, kAnyOldSpace) #define FOUR_CASES(byte_code) \ case byte_code: \ case byte_code + 1: \ case byte_code + 2: \ case byte_code + 3: #define SIXTEEN_CASES(byte_code) \ FOUR_CASES(byte_code) \ FOUR_CASES(byte_code + 4) \ FOUR_CASES(byte_code + 8) \ FOUR_CASES(byte_code + 12) #define COMMON_RAW_LENGTHS(f) \ f(1) \ f(2) \ f(3) \ f(4) \ f(5) \ f(6) \ f(7) \ f(8) \ f(9) \ f(10) \ f(11) \ f(12) \ f(13) \ f(14) \ f(15) \ f(16) \ f(17) \ f(18) \ f(19) \ f(20) \ f(21) \ f(22) \ f(23) \ f(24) \ f(25) \ f(26) \ f(27) \ f(28) \ f(29) \ f(30) \ f(31) // We generate 15 cases and bodies that process special tags that combine // the raw data tag and the length into one byte. #define RAW_CASE(index) \ case kRawData + index: { \ byte* raw_data_out = reinterpret_cast<byte*>(current); \ source_->CopyRaw(raw_data_out, index * kPointerSize); \ current = \ reinterpret_cast<Object**>(raw_data_out + index * kPointerSize); \ break; \ } COMMON_RAW_LENGTHS(RAW_CASE) #undef RAW_CASE // Deserialize a chunk of raw data that doesn't have one of the popular // lengths. case kRawData: { int size = source_->GetInt(); byte* raw_data_out = reinterpret_cast<byte*>(current); source_->CopyRaw(raw_data_out, size); break; } SIXTEEN_CASES(kRootArrayConstants + kNoSkipDistance) SIXTEEN_CASES(kRootArrayConstants + kNoSkipDistance + 16) { int root_id = RootArrayConstantFromByteCode(data); Object* object = isolate->heap()->roots_array_start()[root_id]; DCHECK(!isolate->heap()->InNewSpace(object)); *current++ = object; break; } SIXTEEN_CASES(kRootArrayConstants + kHasSkipDistance) SIXTEEN_CASES(kRootArrayConstants + kHasSkipDistance + 16) { int root_id = RootArrayConstantFromByteCode(data); int skip = source_->GetInt(); current = reinterpret_cast<Object**>( reinterpret_cast<intptr_t>(current) + skip); Object* object = isolate->heap()->roots_array_start()[root_id]; DCHECK(!isolate->heap()->InNewSpace(object)); *current++ = object; break; } case kRepeat: { int repeats = source_->GetInt(); Object* object = current[-1]; DCHECK(!isolate->heap()->InNewSpace(object)); for (int i = 0; i < repeats; i++) current[i] = object; current += repeats; break; } STATIC_ASSERT(kRootArrayNumberOfConstantEncodings == Heap::kOldSpaceRoots); STATIC_ASSERT(kMaxRepeats == 13); case kConstantRepeat: FOUR_CASES(kConstantRepeat + 1) FOUR_CASES(kConstantRepeat + 5) FOUR_CASES(kConstantRepeat + 9) { int repeats = RepeatsForCode(data); Object* object = current[-1]; DCHECK(!isolate->heap()->InNewSpace(object)); for (int i = 0; i < repeats; i++) current[i] = object; current += repeats; break; } // Deserialize a new object and write a pointer to it to the current // object. ALL_SPACES(kNewObject, kPlain, kStartOfObject) // Support for direct instruction pointers in functions. It's an inner // pointer because it points at the entry point, not at the start of the // code object. CASE_STATEMENT(kNewObject, kPlain, kInnerPointer, CODE_SPACE) CASE_BODY(kNewObject, kPlain, kInnerPointer, CODE_SPACE) // Deserialize a new code object and write a pointer to its first // instruction to the current code object. ALL_SPACES(kNewObject, kFromCode, kInnerPointer) // Find a recently deserialized object using its offset from the current // allocation point and write a pointer to it to the current object. ALL_SPACES(kBackref, kPlain, kStartOfObject) ALL_SPACES(kBackrefWithSkip, kPlain, kStartOfObject) #if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL || \ defined(V8_TARGET_ARCH_MIPS64) // Deserialize a new object from pointer found in code and write // a pointer to it to the current object. Required only for MIPS or ARM // with ool constant pool, and omitted on the other architectures because // it is fully unrolled and would cause bloat. ALL_SPACES(kNewObject, kFromCode, kStartOfObject) // Find a recently deserialized code object using its offset from the // current allocation point and write a pointer to it to the current // object. Required only for MIPS or ARM with ool constant pool. ALL_SPACES(kBackref, kFromCode, kStartOfObject) ALL_SPACES(kBackrefWithSkip, kFromCode, kStartOfObject) #endif // Find a recently deserialized code object using its offset from the // current allocation point and write a pointer to its first instruction // to the current code object or the instruction pointer in a function // object. ALL_SPACES(kBackref, kFromCode, kInnerPointer) ALL_SPACES(kBackrefWithSkip, kFromCode, kInnerPointer) ALL_SPACES(kBackref, kPlain, kInnerPointer) ALL_SPACES(kBackrefWithSkip, kPlain, kInnerPointer) // Find an object in the roots array and write a pointer to it to the // current object. CASE_STATEMENT(kRootArray, kPlain, kStartOfObject, 0) CASE_BODY(kRootArray, kPlain, kStartOfObject, 0) #if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL || \ defined(V8_TARGET_ARCH_MIPS64) // Find an object in the roots array and write a pointer to it to in code. CASE_STATEMENT(kRootArray, kFromCode, kStartOfObject, 0) CASE_BODY(kRootArray, kFromCode, kStartOfObject, 0) #endif // Find an object in the partial snapshots cache and write a pointer to it // to the current object. CASE_STATEMENT(kPartialSnapshotCache, kPlain, kStartOfObject, 0) CASE_BODY(kPartialSnapshotCache, kPlain, kStartOfObject, 0) // Find an code entry in the partial snapshots cache and // write a pointer to it to the current object. CASE_STATEMENT(kPartialSnapshotCache, kPlain, kInnerPointer, 0) CASE_BODY(kPartialSnapshotCache, kPlain, kInnerPointer, 0) // Find an external reference and write a pointer to it to the current // object. CASE_STATEMENT(kExternalReference, kPlain, kStartOfObject, 0) CASE_BODY(kExternalReference, kPlain, kStartOfObject, 0) // Find an external reference and write a pointer to it in the current // code object. CASE_STATEMENT(kExternalReference, kFromCode, kStartOfObject, 0) CASE_BODY(kExternalReference, kFromCode, kStartOfObject, 0) // Find a builtin and write a pointer to it to the current object. CASE_STATEMENT(kBuiltin, kPlain, kStartOfObject, 0) CASE_BODY(kBuiltin, kPlain, kStartOfObject, 0) #if V8_OOL_CONSTANT_POOL // Find a builtin code entry and write a pointer to it to the current // object. CASE_STATEMENT(kBuiltin, kPlain, kInnerPointer, 0) CASE_BODY(kBuiltin, kPlain, kInnerPointer, 0) #endif // Find a builtin and write a pointer to it in the current code object. CASE_STATEMENT(kBuiltin, kFromCode, kInnerPointer, 0) CASE_BODY(kBuiltin, kFromCode, kInnerPointer, 0) // Find an object in the attached references and write a pointer to it to // the current object. CASE_STATEMENT(kAttachedReference, kPlain, kStartOfObject, 0) CASE_BODY(kAttachedReference, kPlain, kStartOfObject, 0) CASE_STATEMENT(kAttachedReference, kPlain, kInnerPointer, 0) CASE_BODY(kAttachedReference, kPlain, kInnerPointer, 0) CASE_STATEMENT(kAttachedReference, kFromCode, kInnerPointer, 0) CASE_BODY(kAttachedReference, kFromCode, kInnerPointer, 0) #undef CASE_STATEMENT #undef CASE_BODY #undef ALL_SPACES case kSkip: { int size = source_->GetInt(); current = reinterpret_cast<Object**>( reinterpret_cast<intptr_t>(current) + size); break; } case kNativesStringResource: { int index = source_->Get(); Vector<const char> source_vector = Natives::GetRawScriptSource(index); NativesExternalStringResource* resource = new NativesExternalStringResource(isolate->bootstrapper(), source_vector.start(), source_vector.length()); *current++ = reinterpret_cast<Object*>(resource); break; } case kSynchronize: { // If we get here then that indicates that you have a mismatch between // the number of GC roots when serializing and deserializing. UNREACHABLE(); } default: UNREACHABLE(); } } DCHECK_EQ(limit, current); } Serializer::Serializer(Isolate* isolate, SnapshotByteSink* sink) : isolate_(isolate), sink_(sink), external_reference_encoder_(new ExternalReferenceEncoder(isolate)), root_index_wave_front_(0), code_address_map_(NULL) { // The serializer is meant to be used only to generate initial heap images // from a context in which there is only one isolate. for (int i = 0; i <= LAST_SPACE; i++) { fullness_[i] = 0; } } Serializer::~Serializer() { delete external_reference_encoder_; if (code_address_map_ != NULL) delete code_address_map_; } void StartupSerializer::SerializeStrongReferences() { Isolate* isolate = this->isolate(); // No active threads. CHECK_EQ(NULL, isolate->thread_manager()->FirstThreadStateInUse()); // No active or weak handles. CHECK(isolate->handle_scope_implementer()->blocks()->is_empty()); CHECK_EQ(0, isolate->global_handles()->NumberOfWeakHandles()); CHECK_EQ(0, isolate->eternal_handles()->NumberOfHandles()); // We don't support serializing installed extensions. CHECK(!isolate->has_installed_extensions()); isolate->heap()->IterateSmiRoots(this); isolate->heap()->IterateStrongRoots(this, VISIT_ONLY_STRONG); } void PartialSerializer::Serialize(Object** object) { this->VisitPointer(object); Pad(); } bool Serializer::ShouldBeSkipped(Object** current) { Object** roots = isolate()->heap()->roots_array_start(); return current == &roots[Heap::kStoreBufferTopRootIndex] || current == &roots[Heap::kStackLimitRootIndex] || current == &roots[Heap::kRealStackLimitRootIndex]; } void Serializer::VisitPointers(Object** start, Object** end) { Isolate* isolate = this->isolate();; for (Object** current = start; current < end; current++) { if (start == isolate->heap()->roots_array_start()) { root_index_wave_front_ = Max(root_index_wave_front_, static_cast<intptr_t>(current - start)); } if (ShouldBeSkipped(current)) { sink_->Put(kSkip, "Skip"); sink_->PutInt(kPointerSize, "SkipOneWord"); } else if ((*current)->IsSmi()) { sink_->Put(kRawData + 1, "Smi"); for (int i = 0; i < kPointerSize; i++) { sink_->Put(reinterpret_cast<byte*>(current)[i], "Byte"); } } else { SerializeObject(*current, kPlain, kStartOfObject, 0); } } } // This ensures that the partial snapshot cache keeps things alive during GC and // tracks their movement. When it is called during serialization of the startup // snapshot nothing happens. When the partial (context) snapshot is created, // this array is populated with the pointers that the partial snapshot will // need. As that happens we emit serialized objects to the startup snapshot // that correspond to the elements of this cache array. On deserialization we // therefore need to visit the cache array. This fills it up with pointers to // deserialized objects. void SerializerDeserializer::Iterate(Isolate* isolate, ObjectVisitor* visitor) { if (isolate->serializer_enabled()) return; for (int i = 0; ; i++) { if (isolate->serialize_partial_snapshot_cache_length() <= i) { // Extend the array ready to get a value from the visitor when // deserializing. isolate->PushToPartialSnapshotCache(Smi::FromInt(0)); } Object** cache = isolate->serialize_partial_snapshot_cache(); visitor->VisitPointers(&cache[i], &cache[i + 1]); // Sentinel is the undefined object, which is a root so it will not normally // be found in the cache. if (cache[i] == isolate->heap()->undefined_value()) { break; } } } int PartialSerializer::PartialSnapshotCacheIndex(HeapObject* heap_object) { Isolate* isolate = this->isolate(); for (int i = 0; i < isolate->serialize_partial_snapshot_cache_length(); i++) { Object* entry = isolate->serialize_partial_snapshot_cache()[i]; if (entry == heap_object) return i; } // We didn't find the object in the cache. So we add it to the cache and // then visit the pointer so that it becomes part of the startup snapshot // and we can refer to it from the partial snapshot. int length = isolate->serialize_partial_snapshot_cache_length(); isolate->PushToPartialSnapshotCache(heap_object); startup_serializer_->VisitPointer(reinterpret_cast<Object**>(&heap_object)); // We don't recurse from the startup snapshot generator into the partial // snapshot generator. DCHECK(length == isolate->serialize_partial_snapshot_cache_length() - 1); return length; } int Serializer::RootIndex(HeapObject* heap_object, HowToCode from) { Heap* heap = isolate()->heap(); if (heap->InNewSpace(heap_object)) return kInvalidRootIndex; for (int i = 0; i < root_index_wave_front_; i++) { Object* root = heap->roots_array_start()[i]; if (!root->IsSmi() && root == heap_object) { return i; } } return kInvalidRootIndex; } // Encode the location of an already deserialized object in order to write its // location into a later object. We can encode the location as an offset from // the start of the deserialized objects or as an offset backwards from the // current allocation pointer. void Serializer::SerializeReferenceToPreviousObject(HeapObject* heap_object, HowToCode how_to_code, WhereToPoint where_to_point, int skip) { int space = SpaceOfObject(heap_object); int address = address_mapper_.MappedTo(heap_object); int offset = CurrentAllocationAddress(space) - address; // Shift out the bits that are always 0. offset >>= kObjectAlignmentBits; if (skip == 0) { sink_->Put(kBackref + how_to_code + where_to_point + space, "BackRefSer"); } else { sink_->Put(kBackrefWithSkip + how_to_code + where_to_point + space, "BackRefSerWithSkip"); sink_->PutInt(skip, "BackRefSkipDistance"); } sink_->PutInt(offset, "offset"); } void StartupSerializer::SerializeObject( Object* o, HowToCode how_to_code, WhereToPoint where_to_point, int skip) { CHECK(o->IsHeapObject()); HeapObject* heap_object = HeapObject::cast(o); DCHECK(!heap_object->IsJSFunction()); int root_index; if ((root_index = RootIndex(heap_object, how_to_code)) != kInvalidRootIndex) { PutRoot(root_index, heap_object, how_to_code, where_to_point, skip); return; } if (address_mapper_.IsMapped(heap_object)) { SerializeReferenceToPreviousObject(heap_object, how_to_code, where_to_point, skip); } else { if (skip != 0) { sink_->Put(kSkip, "FlushPendingSkip"); sink_->PutInt(skip, "SkipDistance"); } // Object has not yet been serialized. Serialize it here. ObjectSerializer object_serializer(this, heap_object, sink_, how_to_code, where_to_point); object_serializer.Serialize(); } } void StartupSerializer::SerializeWeakReferences() { // This phase comes right after the partial serialization (of the snapshot). // After we have done the partial serialization the partial snapshot cache // will contain some references needed to decode the partial snapshot. We // add one entry with 'undefined' which is the sentinel that the deserializer // uses to know it is done deserializing the array. Object* undefined = isolate()->heap()->undefined_value(); VisitPointer(&undefined); isolate()->heap()->IterateWeakRoots(this, VISIT_ALL); Pad(); } void Serializer::PutRoot(int root_index, HeapObject* object, SerializerDeserializer::HowToCode how_to_code, SerializerDeserializer::WhereToPoint where_to_point, int skip) { if (how_to_code == kPlain && where_to_point == kStartOfObject && root_index < kRootArrayNumberOfConstantEncodings && !isolate()->heap()->InNewSpace(object)) { if (skip == 0) { sink_->Put(kRootArrayConstants + kNoSkipDistance + root_index, "RootConstant"); } else { sink_->Put(kRootArrayConstants + kHasSkipDistance + root_index, "RootConstant"); sink_->PutInt(skip, "SkipInPutRoot"); } } else { if (skip != 0) { sink_->Put(kSkip, "SkipFromPutRoot"); sink_->PutInt(skip, "SkipFromPutRootDistance"); } sink_->Put(kRootArray + how_to_code + where_to_point, "RootSerialization"); sink_->PutInt(root_index, "root_index"); } } void PartialSerializer::SerializeObject( Object* o, HowToCode how_to_code, WhereToPoint where_to_point, int skip) { CHECK(o->IsHeapObject()); HeapObject* heap_object = HeapObject::cast(o); if (heap_object->IsMap()) { // The code-caches link to context-specific code objects, which // the startup and context serializes cannot currently handle. DCHECK(Map::cast(heap_object)->code_cache() == heap_object->GetHeap()->empty_fixed_array()); } int root_index; if ((root_index = RootIndex(heap_object, how_to_code)) != kInvalidRootIndex) { PutRoot(root_index, heap_object, how_to_code, where_to_point, skip); return; } if (ShouldBeInThePartialSnapshotCache(heap_object)) { if (skip != 0) { sink_->Put(kSkip, "SkipFromSerializeObject"); sink_->PutInt(skip, "SkipDistanceFromSerializeObject"); } int cache_index = PartialSnapshotCacheIndex(heap_object); sink_->Put(kPartialSnapshotCache + how_to_code + where_to_point, "PartialSnapshotCache"); sink_->PutInt(cache_index, "partial_snapshot_cache_index"); return; } // Pointers from the partial snapshot to the objects in the startup snapshot // should go through the root array or through the partial snapshot cache. // If this is not the case you may have to add something to the root array. DCHECK(!startup_serializer_->address_mapper()->IsMapped(heap_object)); // All the internalized strings that the partial snapshot needs should be // either in the root table or in the partial snapshot cache. DCHECK(!heap_object->IsInternalizedString()); if (address_mapper_.IsMapped(heap_object)) { SerializeReferenceToPreviousObject(heap_object, how_to_code, where_to_point, skip); } else { if (skip != 0) { sink_->Put(kSkip, "SkipFromSerializeObject"); sink_->PutInt(skip, "SkipDistanceFromSerializeObject"); } // Object has not yet been serialized. Serialize it here. ObjectSerializer serializer(this, heap_object, sink_, how_to_code, where_to_point); serializer.Serialize(); } } void Serializer::ObjectSerializer::Serialize() { int space = Serializer::SpaceOfObject(object_); int size = object_->Size(); sink_->Put(kNewObject + reference_representation_ + space, "ObjectSerialization"); sink_->PutInt(size >> kObjectAlignmentBits, "Size in words"); if (serializer_->code_address_map_) { const char* code_name = serializer_->code_address_map_->Lookup(object_->address()); LOG(serializer_->isolate_, CodeNameEvent(object_->address(), sink_->Position(), code_name)); LOG(serializer_->isolate_, SnapshotPositionEvent(object_->address(), sink_->Position())); } // Mark this object as already serialized. int offset = serializer_->Allocate(space, size); serializer_->address_mapper()->AddMapping(object_, offset); // Serialize the map (first word of the object). serializer_->SerializeObject(object_->map(), kPlain, kStartOfObject, 0); // Serialize the rest of the object. CHECK_EQ(0, bytes_processed_so_far_); bytes_processed_so_far_ = kPointerSize; object_->IterateBody(object_->map()->instance_type(), size, this); OutputRawData(object_->address() + size); } void Serializer::ObjectSerializer::VisitPointers(Object** start, Object** end) { Object** current = start; while (current < end) { while (current < end && (*current)->IsSmi()) current++; if (current < end) OutputRawData(reinterpret_cast<Address>(current)); while (current < end && !(*current)->IsSmi()) { HeapObject* current_contents = HeapObject::cast(*current); int root_index = serializer_->RootIndex(current_contents, kPlain); // Repeats are not subject to the write barrier so there are only some // objects that can be used in a repeat encoding. These are the early // ones in the root array that are never in new space. if (current != start && root_index != kInvalidRootIndex && root_index < kRootArrayNumberOfConstantEncodings && current_contents == current[-1]) { DCHECK(!serializer_->isolate()->heap()->InNewSpace(current_contents)); int repeat_count = 1; while (¤t[repeat_count] < end - 1 && current[repeat_count] == current_contents) { repeat_count++; } current += repeat_count; bytes_processed_so_far_ += repeat_count * kPointerSize; if (repeat_count > kMaxRepeats) { sink_->Put(kRepeat, "SerializeRepeats"); sink_->PutInt(repeat_count, "SerializeRepeats"); } else { sink_->Put(CodeForRepeats(repeat_count), "SerializeRepeats"); } } else { serializer_->SerializeObject( current_contents, kPlain, kStartOfObject, 0); bytes_processed_so_far_ += kPointerSize; current++; } } } } void Serializer::ObjectSerializer::VisitEmbeddedPointer(RelocInfo* rinfo) { // Out-of-line constant pool entries will be visited by the ConstantPoolArray. if (FLAG_enable_ool_constant_pool && rinfo->IsInConstantPool()) return; int skip = OutputRawData(rinfo->target_address_address(), kCanReturnSkipInsteadOfSkipping); HowToCode how_to_code = rinfo->IsCodedSpecially() ? kFromCode : kPlain; Object* object = rinfo->target_object(); serializer_->SerializeObject(object, how_to_code, kStartOfObject, skip); bytes_processed_so_far_ += rinfo->target_address_size(); } void Serializer::ObjectSerializer::VisitExternalReference(Address* p) { int skip = OutputRawData(reinterpret_cast<Address>(p), kCanReturnSkipInsteadOfSkipping); sink_->Put(kExternalReference + kPlain + kStartOfObject, "ExternalRef"); sink_->PutInt(skip, "SkipB4ExternalRef"); Address target = *p; sink_->PutInt(serializer_->EncodeExternalReference(target), "reference id"); bytes_processed_so_far_ += kPointerSize; } void Serializer::ObjectSerializer::VisitExternalReference(RelocInfo* rinfo) { int skip = OutputRawData(rinfo->target_address_address(), kCanReturnSkipInsteadOfSkipping); HowToCode how_to_code = rinfo->IsCodedSpecially() ? kFromCode : kPlain; sink_->Put(kExternalReference + how_to_code + kStartOfObject, "ExternalRef"); sink_->PutInt(skip, "SkipB4ExternalRef"); Address target = rinfo->target_reference(); sink_->PutInt(serializer_->EncodeExternalReference(target), "reference id"); bytes_processed_so_far_ += rinfo->target_address_size(); } void Serializer::ObjectSerializer::VisitRuntimeEntry(RelocInfo* rinfo) { int skip = OutputRawData(rinfo->target_address_address(), kCanReturnSkipInsteadOfSkipping); HowToCode how_to_code = rinfo->IsCodedSpecially() ? kFromCode : kPlain; sink_->Put(kExternalReference + how_to_code + kStartOfObject, "ExternalRef"); sink_->PutInt(skip, "SkipB4ExternalRef"); Address target = rinfo->target_address(); sink_->PutInt(serializer_->EncodeExternalReference(target), "reference id"); bytes_processed_so_far_ += rinfo->target_address_size(); } void Serializer::ObjectSerializer::VisitCodeTarget(RelocInfo* rinfo) { // Out-of-line constant pool entries will be visited by the ConstantPoolArray. if (FLAG_enable_ool_constant_pool && rinfo->IsInConstantPool()) return; int skip = OutputRawData(rinfo->target_address_address(), kCanReturnSkipInsteadOfSkipping); Code* object = Code::GetCodeFromTargetAddress(rinfo->target_address()); serializer_->SerializeObject(object, kFromCode, kInnerPointer, skip); bytes_processed_so_far_ += rinfo->target_address_size(); } void Serializer::ObjectSerializer::VisitCodeEntry(Address entry_address) { int skip = OutputRawData(entry_address, kCanReturnSkipInsteadOfSkipping); Code* object = Code::cast(Code::GetObjectFromEntryAddress(entry_address)); serializer_->SerializeObject(object, kPlain, kInnerPointer, skip); bytes_processed_so_far_ += kPointerSize; } void Serializer::ObjectSerializer::VisitCell(RelocInfo* rinfo) { // Out-of-line constant pool entries will be visited by the ConstantPoolArray. if (FLAG_enable_ool_constant_pool && rinfo->IsInConstantPool()) return; int skip = OutputRawData(rinfo->pc(), kCanReturnSkipInsteadOfSkipping); Cell* object = Cell::cast(rinfo->target_cell()); serializer_->SerializeObject(object, kPlain, kInnerPointer, skip); bytes_processed_so_far_ += kPointerSize; } void Serializer::ObjectSerializer::VisitExternalOneByteString( v8::String::ExternalOneByteStringResource** resource_pointer) { Address references_start = reinterpret_cast<Address>(resource_pointer); OutputRawData(references_start); for (int i = 0; i < Natives::GetBuiltinsCount(); i++) { Object* source = serializer_->isolate()->heap()->natives_source_cache()->get(i); if (!source->IsUndefined()) { ExternalOneByteString* string = ExternalOneByteString::cast(source); typedef v8::String::ExternalOneByteStringResource Resource; const Resource* resource = string->resource(); if (resource == *resource_pointer) { sink_->Put(kNativesStringResource, "NativesStringResource"); sink_->PutSection(i, "NativesStringResourceEnd"); bytes_processed_so_far_ += sizeof(resource); return; } } } // One of the strings in the natives cache should match the resource. We // can't serialize any other kinds of external strings. UNREACHABLE(); } static Code* CloneCodeObject(HeapObject* code) { Address copy = new byte[code->Size()]; MemCopy(copy, code->address(), code->Size()); return Code::cast(HeapObject::FromAddress(copy)); } static void WipeOutRelocations(Code* code) { int mode_mask = RelocInfo::kCodeTargetMask | RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) | RelocInfo::ModeMask(RelocInfo::EXTERNAL_REFERENCE) | RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY); for (RelocIterator it(code, mode_mask); !it.done(); it.next()) { if (!(FLAG_enable_ool_constant_pool && it.rinfo()->IsInConstantPool())) { it.rinfo()->WipeOut(); } } } int Serializer::ObjectSerializer::OutputRawData( Address up_to, Serializer::ObjectSerializer::ReturnSkip return_skip) { Address object_start = object_->address(); int base = bytes_processed_so_far_; int up_to_offset = static_cast<int>(up_to - object_start); int to_skip = up_to_offset - bytes_processed_so_far_; int bytes_to_output = to_skip; bytes_processed_so_far_ += to_skip; // This assert will fail if the reloc info gives us the target_address_address // locations in a non-ascending order. Luckily that doesn't happen. DCHECK(to_skip >= 0); bool outputting_code = false; if (to_skip != 0 && code_object_ && !code_has_been_output_) { // Output the code all at once and fix later. bytes_to_output = object_->Size() + to_skip - bytes_processed_so_far_; outputting_code = true; code_has_been_output_ = true; } if (bytes_to_output != 0 && (!code_object_ || outputting_code)) { #define RAW_CASE(index) \ if (!outputting_code && bytes_to_output == index * kPointerSize && \ index * kPointerSize == to_skip) { \ sink_->PutSection(kRawData + index, "RawDataFixed"); \ to_skip = 0; /* This insn already skips. */ \ } else /* NOLINT */ COMMON_RAW_LENGTHS(RAW_CASE) #undef RAW_CASE { /* NOLINT */ // We always end up here if we are outputting the code of a code object. sink_->Put(kRawData, "RawData"); sink_->PutInt(bytes_to_output, "length"); } // To make snapshots reproducible, we need to wipe out all pointers in code. if (code_object_) { Code* code = CloneCodeObject(object_); WipeOutRelocations(code); // We need to wipe out the header fields *after* wiping out the // relocations, because some of these fields are needed for the latter. code->WipeOutHeader(); object_start = code->address(); } const char* description = code_object_ ? "Code" : "Byte"; for (int i = 0; i < bytes_to_output; i++) { sink_->PutSection(object_start[base + i], description); } if (code_object_) delete[] object_start; } if (to_skip != 0 && return_skip == kIgnoringReturn) { sink_->Put(kSkip, "Skip"); sink_->PutInt(to_skip, "SkipDistance"); to_skip = 0; } return to_skip; } int Serializer::SpaceOfObject(HeapObject* object) { for (int i = FIRST_SPACE; i <= LAST_SPACE; i++) { AllocationSpace s = static_cast<AllocationSpace>(i); if (object->GetHeap()->InSpace(object, s)) { DCHECK(i < kNumberOfSpaces); return i; } } UNREACHABLE(); return 0; } int Serializer::Allocate(int space, int size) { CHECK(space >= 0 && space < kNumberOfSpaces); int allocation_address = fullness_[space]; fullness_[space] = allocation_address + size; return allocation_address; } int Serializer::SpaceAreaSize(int space) { if (space == CODE_SPACE) { return isolate_->memory_allocator()->CodePageAreaSize(); } else { return Page::kPageSize - Page::kObjectStartOffset; } } void Serializer::Pad() { // The non-branching GetInt will read up to 3 bytes too far, so we need // to pad the snapshot to make sure we don't read over the end. for (unsigned i = 0; i < sizeof(int32_t) - 1; i++) { sink_->Put(kNop, "Padding"); } } void Serializer::InitializeCodeAddressMap() { isolate_->InitializeLoggingAndCounters(); code_address_map_ = new CodeAddressMap(isolate_); } ScriptData* CodeSerializer::Serialize(Isolate* isolate, Handle<SharedFunctionInfo> info, Handle<String> source) { base::ElapsedTimer timer; if (FLAG_profile_deserialization) timer.Start(); // Serialize code object. List<byte> payload; ListSnapshotSink list_sink(&payload); DebugSnapshotSink debug_sink(&list_sink); SnapshotByteSink* sink = FLAG_trace_code_serializer ? static_cast<SnapshotByteSink*>(&debug_sink) : static_cast<SnapshotByteSink*>(&list_sink); CodeSerializer cs(isolate, sink, *source); DisallowHeapAllocation no_gc; Object** location = Handle<Object>::cast(info).location(); cs.VisitPointer(location); cs.Pad(); SerializedCodeData data(&payload, &cs); ScriptData* script_data = data.GetScriptData(); if (FLAG_profile_deserialization) { double ms = timer.Elapsed().InMillisecondsF(); int length = script_data->length(); PrintF("[Serializing to %d bytes took %0.3f ms]\n", length, ms); } return script_data; } void CodeSerializer::SerializeObject(Object* o, HowToCode how_to_code, WhereToPoint where_to_point, int skip) { CHECK(o->IsHeapObject()); HeapObject* heap_object = HeapObject::cast(o); // The code-caches link to context-specific code objects, which // the startup and context serializes cannot currently handle. DCHECK(!heap_object->IsMap() || Map::cast(heap_object)->code_cache() == heap_object->GetHeap()->empty_fixed_array()); int root_index; if ((root_index = RootIndex(heap_object, how_to_code)) != kInvalidRootIndex) { PutRoot(root_index, heap_object, how_to_code, where_to_point, skip); return; } // TODO(yangguo) wire up global object. // TODO(yangguo) We cannot deal with different hash seeds yet. DCHECK(!heap_object->IsHashTable()); if (address_mapper_.IsMapped(heap_object)) { SerializeReferenceToPreviousObject(heap_object, how_to_code, where_to_point, skip); return; } if (heap_object->IsCode()) { Code* code_object = Code::cast(heap_object); if (code_object->kind() == Code::BUILTIN) { SerializeBuiltin(code_object, how_to_code, where_to_point, skip); return; } if (code_object->IsCodeStubOrIC()) { SerializeCodeStub(code_object, how_to_code, where_to_point, skip); return; } code_object->ClearInlineCaches(); } if (heap_object == source_) { SerializeSourceObject(how_to_code, where_to_point, skip); return; } SerializeHeapObject(heap_object, how_to_code, where_to_point, skip); } void CodeSerializer::SerializeHeapObject(HeapObject* heap_object, HowToCode how_to_code, WhereToPoint where_to_point, int skip) { if (heap_object->IsScript()) { // The wrapper cache uses a Foreign object to point to a global handle. // However, the object visitor expects foreign objects to point to external // references. Clear the cache to avoid this issue. Script::cast(heap_object)->ClearWrapperCache(); } if (skip != 0) { sink_->Put(kSkip, "SkipFromSerializeObject"); sink_->PutInt(skip, "SkipDistanceFromSerializeObject"); } if (FLAG_trace_code_serializer) { PrintF("Encoding heap object: "); heap_object->ShortPrint(); PrintF("\n"); } // Object has not yet been serialized. Serialize it here. ObjectSerializer serializer(this, heap_object, sink_, how_to_code, where_to_point); serializer.Serialize(); } void CodeSerializer::SerializeBuiltin(Code* builtin, HowToCode how_to_code, WhereToPoint where_to_point, int skip) { if (skip != 0) { sink_->Put(kSkip, "SkipFromSerializeBuiltin"); sink_->PutInt(skip, "SkipDistanceFromSerializeBuiltin"); } DCHECK((how_to_code == kPlain && where_to_point == kStartOfObject) || (how_to_code == kPlain && where_to_point == kInnerPointer) || (how_to_code == kFromCode && where_to_point == kInnerPointer)); int builtin_index = builtin->builtin_index(); DCHECK_LT(builtin_index, Builtins::builtin_count); DCHECK_LE(0, builtin_index); if (FLAG_trace_code_serializer) { PrintF("Encoding builtin: %s\n", isolate()->builtins()->name(builtin_index)); } sink_->Put(kBuiltin + how_to_code + where_to_point, "Builtin"); sink_->PutInt(builtin_index, "builtin_index"); } void CodeSerializer::SerializeCodeStub(Code* code, HowToCode how_to_code, WhereToPoint where_to_point, int skip) { DCHECK((how_to_code == kPlain && where_to_point == kStartOfObject) || (how_to_code == kPlain && where_to_point == kInnerPointer) || (how_to_code == kFromCode && where_to_point == kInnerPointer)); uint32_t stub_key = code->stub_key(); if (stub_key == CodeStub::NoCacheKey()) { if (FLAG_trace_code_serializer) { PrintF("Encoding uncacheable code stub as heap object\n"); } SerializeHeapObject(code, how_to_code, where_to_point, skip); return; } if (skip != 0) { sink_->Put(kSkip, "SkipFromSerializeCodeStub"); sink_->PutInt(skip, "SkipDistanceFromSerializeCodeStub"); } int index = AddCodeStubKey(stub_key) + kCodeStubsBaseIndex; if (FLAG_trace_code_serializer) { PrintF("Encoding code stub %s as %d\n", CodeStub::MajorName(CodeStub::MajorKeyFromKey(stub_key), false), index); } sink_->Put(kAttachedReference + how_to_code + where_to_point, "CodeStub"); sink_->PutInt(index, "CodeStub key"); } int CodeSerializer::AddCodeStubKey(uint32_t stub_key) { // TODO(yangguo) Maybe we need a hash table for a faster lookup than O(n^2). int index = 0; while (index < stub_keys_.length()) { if (stub_keys_[index] == stub_key) return index; index++; } stub_keys_.Add(stub_key); return index; } void CodeSerializer::SerializeSourceObject(HowToCode how_to_code, WhereToPoint where_to_point, int skip) { if (skip != 0) { sink_->Put(kSkip, "SkipFromSerializeSourceObject"); sink_->PutInt(skip, "SkipDistanceFromSerializeSourceObject"); } if (FLAG_trace_code_serializer) { PrintF("Encoding source object\n"); } DCHECK(how_to_code == kPlain && where_to_point == kStartOfObject); sink_->Put(kAttachedReference + how_to_code + where_to_point, "Source"); sink_->PutInt(kSourceObjectIndex, "kSourceObjectIndex"); } Handle<SharedFunctionInfo> CodeSerializer::Deserialize(Isolate* isolate, ScriptData* data, Handle<String> source) { base::ElapsedTimer timer; if (FLAG_profile_deserialization) timer.Start(); Object* root; { HandleScope scope(isolate); SerializedCodeData scd(data, *source); SnapshotByteSource payload(scd.Payload(), scd.PayloadLength()); Deserializer deserializer(&payload); STATIC_ASSERT(NEW_SPACE == 0); for (int i = NEW_SPACE; i <= PROPERTY_CELL_SPACE; i++) { deserializer.set_reservation(i, scd.GetReservation(i)); } // Prepare and register list of attached objects. Vector<const uint32_t> code_stub_keys = scd.CodeStubKeys(); Vector<Handle<Object> > attached_objects = Vector<Handle<Object> >::New( code_stub_keys.length() + kCodeStubsBaseIndex); attached_objects[kSourceObjectIndex] = source; for (int i = 0; i < code_stub_keys.length(); i++) { attached_objects[i + kCodeStubsBaseIndex] = CodeStub::GetCode(isolate, code_stub_keys[i]).ToHandleChecked(); } deserializer.SetAttachedObjects(&attached_objects); // Deserialize. deserializer.DeserializePartial(isolate, &root); deserializer.FlushICacheForNewCodeObjects(); } if (FLAG_profile_deserialization) { double ms = timer.Elapsed().InMillisecondsF(); int length = data->length(); PrintF("[Deserializing from %d bytes took %0.3f ms]\n", length, ms); } return Handle<SharedFunctionInfo>(SharedFunctionInfo::cast(root), isolate); } SerializedCodeData::SerializedCodeData(List<byte>* payload, CodeSerializer* cs) : owns_script_data_(true) { DisallowHeapAllocation no_gc; List<uint32_t>* stub_keys = cs->stub_keys(); // Calculate sizes. int num_stub_keys = stub_keys->length(); int stub_keys_size = stub_keys->length() * kInt32Size; int data_length = kHeaderSize + stub_keys_size + payload->length(); // Allocate backing store and create result data. byte* data = NewArray<byte>(data_length); DCHECK(IsAligned(reinterpret_cast<intptr_t>(data), kPointerAlignment)); script_data_ = new ScriptData(data, data_length); script_data_->AcquireDataOwnership(); // Set header values. SetHeaderValue(kCheckSumOffset, CheckSum(cs->source())); SetHeaderValue(kNumCodeStubKeysOffset, num_stub_keys); SetHeaderValue(kPayloadLengthOffset, payload->length()); STATIC_ASSERT(NEW_SPACE == 0); for (int i = NEW_SPACE; i <= PROPERTY_CELL_SPACE; i++) { SetHeaderValue(kReservationsOffset + i, cs->CurrentAllocationAddress(i)); } // Copy code stub keys. CopyBytes(data + kHeaderSize, reinterpret_cast<byte*>(stub_keys->begin()), stub_keys_size); // Copy serialized data. CopyBytes(data + kHeaderSize + stub_keys_size, payload->begin(), static_cast<size_t>(payload->length())); } bool SerializedCodeData::IsSane(String* source) { return GetHeaderValue(kCheckSumOffset) == CheckSum(source) && PayloadLength() >= SharedFunctionInfo::kSize; } int SerializedCodeData::CheckSum(String* string) { int checksum = Version::Hash(); #ifdef DEBUG uint32_t seed = static_cast<uint32_t>(checksum); checksum = static_cast<int>(IteratingStringHasher::Hash(string, seed)); #endif // DEBUG return checksum; } } } // namespace v8::internal