| // Copyright 2016 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/snapshot/deserializer.h" |
| |
| #include "src/bootstrapper.h" |
| #include "src/external-reference-table.h" |
| #include "src/heap/heap.h" |
| #include "src/isolate.h" |
| #include "src/macro-assembler.h" |
| #include "src/snapshot/natives.h" |
| #include "src/v8.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| void Deserializer::DecodeReservation( |
| Vector<const SerializedData::Reservation> res) { |
| DCHECK_EQ(0, reservations_[NEW_SPACE].length()); |
| STATIC_ASSERT(NEW_SPACE == 0); |
| int current_space = NEW_SPACE; |
| for (auto& r : res) { |
| reservations_[current_space].Add({r.chunk_size(), NULL, NULL}); |
| if (r.is_last()) current_space++; |
| } |
| DCHECK_EQ(kNumberOfSpaces, current_space); |
| for (int i = 0; i < kNumberOfPreallocatedSpaces; i++) current_chunk_[i] = 0; |
| } |
| |
| void Deserializer::FlushICacheForNewIsolate() { |
| DCHECK(!deserializing_user_code_); |
| // The entire isolate is newly deserialized. Simply flush all code pages. |
| for (Page* p : *isolate_->heap()->code_space()) { |
| Assembler::FlushICache(isolate_, p->area_start(), |
| p->area_end() - p->area_start()); |
| } |
| } |
| |
| void Deserializer::FlushICacheForNewCodeObjects() { |
| DCHECK(deserializing_user_code_); |
| for (Code* code : new_code_objects_) { |
| if (FLAG_serialize_age_code) code->PreAge(isolate_); |
| Assembler::FlushICache(isolate_, code->instruction_start(), |
| code->instruction_size()); |
| } |
| } |
| |
| bool Deserializer::ReserveSpace() { |
| #ifdef DEBUG |
| for (int i = NEW_SPACE; i < kNumberOfSpaces; ++i) { |
| CHECK(reservations_[i].length() > 0); |
| } |
| #endif // DEBUG |
| if (!isolate_->heap()->ReserveSpace(reservations_)) return false; |
| for (int i = 0; i < kNumberOfPreallocatedSpaces; i++) { |
| high_water_[i] = reservations_[i][0].start; |
| } |
| return true; |
| } |
| |
| void Deserializer::Initialize(Isolate* isolate) { |
| DCHECK_NULL(isolate_); |
| DCHECK_NOT_NULL(isolate); |
| isolate_ = isolate; |
| DCHECK_NULL(external_reference_table_); |
| external_reference_table_ = ExternalReferenceTable::instance(isolate); |
| CHECK_EQ(magic_number_, |
| SerializedData::ComputeMagicNumber(external_reference_table_)); |
| } |
| |
| void Deserializer::Deserialize(Isolate* isolate) { |
| Initialize(isolate); |
| if (!ReserveSpace()) V8::FatalProcessOutOfMemory("deserializing context"); |
| // No active threads. |
| DCHECK_NULL(isolate_->thread_manager()->FirstThreadStateInUse()); |
| // No active handles. |
| DCHECK(isolate_->handle_scope_implementer()->blocks()->is_empty()); |
| // Partial snapshot cache is not yet populated. |
| DCHECK(isolate_->partial_snapshot_cache()->is_empty()); |
| |
| { |
| DisallowHeapAllocation no_gc; |
| isolate_->heap()->IterateStrongRoots(this, VISIT_ONLY_STRONG_ROOT_LIST); |
| isolate_->heap()->IterateSmiRoots(this); |
| isolate_->heap()->IterateStrongRoots(this, VISIT_ONLY_STRONG); |
| isolate_->heap()->RepairFreeListsAfterDeserialization(); |
| isolate_->heap()->IterateWeakRoots(this, VISIT_ALL); |
| DeserializeDeferredObjects(); |
| FlushICacheForNewIsolate(); |
| } |
| |
| isolate_->heap()->set_native_contexts_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()); |
| } |
| |
| // Issue code events for newly deserialized code objects. |
| LOG_CODE_EVENT(isolate_, LogCodeObjects()); |
| LOG_CODE_EVENT(isolate_, LogBytecodeHandlers()); |
| LOG_CODE_EVENT(isolate_, LogCompiledFunctions()); |
| } |
| |
| MaybeHandle<Object> Deserializer::DeserializePartial( |
| Isolate* isolate, Handle<JSGlobalProxy> global_proxy) { |
| Initialize(isolate); |
| if (!ReserveSpace()) { |
| V8::FatalProcessOutOfMemory("deserialize context"); |
| return MaybeHandle<Object>(); |
| } |
| |
| AddAttachedObject(global_proxy); |
| |
| 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(); |
| Object* root; |
| VisitPointer(&root); |
| DeserializeDeferredObjects(); |
| |
| isolate->heap()->RegisterReservationsForBlackAllocation(reservations_); |
| |
| // 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, which also has to be flushed from instruction cache. |
| CHECK_EQ(start_address, code_space->top()); |
| return Handle<Object>(root, isolate); |
| } |
| |
| MaybeHandle<SharedFunctionInfo> Deserializer::DeserializeCode( |
| Isolate* isolate) { |
| Initialize(isolate); |
| if (!ReserveSpace()) { |
| return Handle<SharedFunctionInfo>(); |
| } else { |
| deserializing_user_code_ = true; |
| HandleScope scope(isolate); |
| Handle<SharedFunctionInfo> result; |
| { |
| DisallowHeapAllocation no_gc; |
| Object* root; |
| VisitPointer(&root); |
| DeserializeDeferredObjects(); |
| FlushICacheForNewCodeObjects(); |
| result = Handle<SharedFunctionInfo>(SharedFunctionInfo::cast(root)); |
| isolate->heap()->RegisterReservationsForBlackAllocation(reservations_); |
| } |
| CommitPostProcessedObjects(isolate); |
| return scope.CloseAndEscape(result); |
| } |
| } |
| |
| Deserializer::~Deserializer() { |
| // TODO(svenpanne) Re-enable this assertion when v8 initialization is fixed. |
| // DCHECK(source_.AtEOF()); |
| } |
| |
| // 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. |
| ReadData(start, end, NEW_SPACE, NULL); |
| } |
| |
| void Deserializer::Synchronize(VisitorSynchronization::SyncTag tag) { |
| static const byte expected = kSynchronize; |
| CHECK_EQ(expected, source_.Get()); |
| } |
| |
| void Deserializer::DeserializeDeferredObjects() { |
| for (int code = source_.Get(); code != kSynchronize; code = source_.Get()) { |
| switch (code) { |
| case kAlignmentPrefix: |
| case kAlignmentPrefix + 1: |
| case kAlignmentPrefix + 2: |
| SetAlignment(code); |
| break; |
| default: { |
| int space = code & kSpaceMask; |
| DCHECK(space <= kNumberOfSpaces); |
| DCHECK(code - space == kNewObject); |
| HeapObject* object = GetBackReferencedObject(space); |
| int size = source_.GetInt() << kPointerSizeLog2; |
| Address obj_address = object->address(); |
| Object** start = reinterpret_cast<Object**>(obj_address + kPointerSize); |
| Object** end = reinterpret_cast<Object**>(obj_address + size); |
| bool filled = ReadData(start, end, space, obj_address); |
| CHECK(filled); |
| DCHECK(CanBeDeferred(object)); |
| PostProcessNewObject(object, space); |
| } |
| } |
| } |
| } |
| |
| // 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()); |
| } |
| |
| bool IsMatch(Object* string) override { |
| // 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)); |
| } |
| |
| uint32_t Hash() override { return hash_; } |
| |
| uint32_t HashForObject(Object* key) override { |
| return String::cast(key)->Hash(); |
| } |
| |
| MUST_USE_RESULT Handle<Object> AsHandle(Isolate* isolate) override { |
| return handle(string_, isolate); |
| } |
| |
| private: |
| String* string_; |
| uint32_t hash_; |
| DisallowHeapAllocation no_gc; |
| }; |
| |
| HeapObject* Deserializer::PostProcessNewObject(HeapObject* obj, int space) { |
| if (deserializing_user_code()) { |
| 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()) { |
| // Canonicalize the internalized string. If it already exists in the |
| // string table, set it to forward to the existing one. |
| StringTableInsertionKey key(string); |
| String* canonical = StringTable::LookupKeyIfExists(isolate_, &key); |
| if (canonical == NULL) { |
| new_internalized_strings_.Add(handle(string)); |
| return string; |
| } else { |
| string->SetForwardedInternalizedString(canonical); |
| return canonical; |
| } |
| } |
| } else if (obj->IsScript()) { |
| new_scripts_.Add(handle(Script::cast(obj))); |
| } else { |
| DCHECK(CanBeDeferred(obj)); |
| } |
| } |
| if (obj->IsAllocationSite()) { |
| DCHECK(obj->IsAllocationSite()); |
| // Allocation sites are present in the snapshot, and must be linked into |
| // a list at deserialization time. |
| AllocationSite* site = AllocationSite::cast(obj); |
| // TODO(mvstanton): consider treating the heap()->allocation_sites_list() |
| // as a (weak) root. If this root is relocated correctly, this becomes |
| // unnecessary. |
| 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); |
| } else if (obj->IsCode()) { |
| // We flush all code pages after deserializing the startup snapshot. In that |
| // case, we only need to remember code objects in the large object space. |
| // When deserializing user code, remember each individual code object. |
| if (deserializing_user_code() || space == LO_SPACE) { |
| new_code_objects_.Add(Code::cast(obj)); |
| } |
| } |
| // Check alignment. |
| DCHECK_EQ(0, Heap::GetFillToAlign(obj->address(), obj->RequiredAlignment())); |
| return obj; |
| } |
| |
| void Deserializer::CommitPostProcessedObjects(Isolate* isolate) { |
| StringTable::EnsureCapacityForDeserialization( |
| isolate, new_internalized_strings_.length()); |
| for (Handle<String> string : new_internalized_strings_) { |
| StringTableInsertionKey key(*string); |
| DCHECK_NULL(StringTable::LookupKeyIfExists(isolate, &key)); |
| StringTable::LookupKey(isolate, &key); |
| } |
| |
| Heap* heap = isolate->heap(); |
| Factory* factory = isolate->factory(); |
| for (Handle<Script> script : new_scripts_) { |
| // Assign a new script id to avoid collision. |
| script->set_id(isolate_->heap()->NextScriptId()); |
| // Add script to list. |
| Handle<Object> list = WeakFixedArray::Add(factory->script_list(), script); |
| heap->SetRootScriptList(*list); |
| } |
| } |
| |
| HeapObject* Deserializer::GetBackReferencedObject(int space) { |
| HeapObject* obj; |
| SerializerReference back_reference = |
| SerializerReference::FromBitfield(source_.GetInt()); |
| if (space == LO_SPACE) { |
| CHECK(back_reference.chunk_index() == 0); |
| uint32_t index = back_reference.large_object_index(); |
| obj = deserialized_large_objects_[index]; |
| } else { |
| DCHECK(space < kNumberOfPreallocatedSpaces); |
| uint32_t chunk_index = back_reference.chunk_index(); |
| DCHECK_LE(chunk_index, current_chunk_[space]); |
| uint32_t chunk_offset = back_reference.chunk_offset(); |
| Address address = reservations_[space][chunk_index].start + chunk_offset; |
| if (next_alignment_ != kWordAligned) { |
| int padding = Heap::GetFillToAlign(address, next_alignment_); |
| next_alignment_ = kWordAligned; |
| DCHECK(padding == 0 || HeapObject::FromAddress(address)->IsFiller()); |
| address += padding; |
| } |
| obj = HeapObject::FromAddress(address); |
| } |
| if (deserializing_user_code() && obj->IsInternalizedString()) { |
| obj = String::cast(obj)->GetForwardedInternalizedString(); |
| } |
| hot_objects_.Add(obj); |
| 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) { |
| Address address; |
| HeapObject* obj; |
| int size = source_.GetInt() << kObjectAlignmentBits; |
| |
| if (next_alignment_ != kWordAligned) { |
| int reserved = size + Heap::GetMaximumFillToAlign(next_alignment_); |
| address = Allocate(space_number, reserved); |
| obj = HeapObject::FromAddress(address); |
| // If one of the following assertions fails, then we are deserializing an |
| // aligned object when the filler maps have not been deserialized yet. |
| // We require filler maps as padding to align the object. |
| Heap* heap = isolate_->heap(); |
| DCHECK(heap->free_space_map()->IsMap()); |
| DCHECK(heap->one_pointer_filler_map()->IsMap()); |
| DCHECK(heap->two_pointer_filler_map()->IsMap()); |
| obj = heap->AlignWithFiller(obj, size, reserved, next_alignment_); |
| address = obj->address(); |
| next_alignment_ = kWordAligned; |
| } else { |
| address = Allocate(space_number, size); |
| obj = HeapObject::FromAddress(address); |
| } |
| |
| isolate_->heap()->OnAllocationEvent(obj, size); |
| Object** current = reinterpret_cast<Object**>(address); |
| Object** limit = current + (size >> kPointerSizeLog2); |
| |
| if (ReadData(current, limit, space_number, address)) { |
| // Only post process if object content has not been deferred. |
| obj = PostProcessNewObject(obj, space_number); |
| } |
| |
| Object* write_back_obj = obj; |
| UnalignedCopy(write_back, &write_back_obj); |
| #ifdef DEBUG |
| if (obj->IsCode()) { |
| DCHECK(space_number == CODE_SPACE || space_number == LO_SPACE); |
| } else { |
| DCHECK(space_number != CODE_SPACE); |
| } |
| #endif // DEBUG |
| } |
| |
| // We know the space requirements before deserialization and can |
| // pre-allocate that reserved space. During deserialization, all we need |
| // to do is to bump up the pointer for each space in the reserved |
| // space. This is also used for fixing back references. |
| // We may have to split up the pre-allocation into several chunks |
| // because it would not fit onto a single page. We do not have to keep |
| // track of when to move to the next chunk. An opcode will signal this. |
| // Since multiple large objects cannot be folded into one large object |
| // space allocation, we have to do an actual allocation when deserializing |
| // each large object. Instead of tracking offset for back references, we |
| // reference large objects by index. |
| Address Deserializer::Allocate(int space_index, int size) { |
| if (space_index == LO_SPACE) { |
| AlwaysAllocateScope scope(isolate_); |
| LargeObjectSpace* lo_space = isolate_->heap()->lo_space(); |
| Executability exec = static_cast<Executability>(source_.Get()); |
| AllocationResult result = lo_space->AllocateRaw(size, exec); |
| HeapObject* obj = HeapObject::cast(result.ToObjectChecked()); |
| deserialized_large_objects_.Add(obj); |
| return obj->address(); |
| } else { |
| DCHECK(space_index < kNumberOfPreallocatedSpaces); |
| Address address = high_water_[space_index]; |
| DCHECK_NOT_NULL(address); |
| high_water_[space_index] += size; |
| #ifdef DEBUG |
| // Assert that the current reserved chunk is still big enough. |
| const Heap::Reservation& reservation = reservations_[space_index]; |
| int chunk_index = current_chunk_[space_index]; |
| CHECK_LE(high_water_[space_index], reservation[chunk_index].end); |
| #endif |
| if (space_index == CODE_SPACE) SkipList::Update(address, size); |
| return address; |
| } |
| } |
| |
| Object** Deserializer::CopyInNativesSource(Vector<const char> source_vector, |
| Object** current) { |
| DCHECK(!isolate_->heap()->deserialization_complete()); |
| NativesExternalStringResource* resource = new NativesExternalStringResource( |
| source_vector.start(), source_vector.length()); |
| Object* resource_obj = reinterpret_cast<Object*>(resource); |
| UnalignedCopy(current++, &resource_obj); |
| return current; |
| } |
| |
| bool Deserializer::ReadData(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 != CODE_SPACE); |
| while (current < limit) { |
| byte data = source_.Get(); |
| switch (data) { |
| #define CASE_STATEMENT(where, how, within, space_number) \ |
| case where + how + within + space_number: \ |
| STATIC_ASSERT((where & ~kWhereMask) == 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 == kBackref) { \ |
| emit_write_barrier = (space_number == NEW_SPACE); \ |
| new_object = GetBackReferencedObject(data & kSpaceMask); \ |
| } else if (where == kBackrefWithSkip) { \ |
| int skip = source_.GetInt(); \ |
| current = reinterpret_cast<Object**>( \ |
| reinterpret_cast<Address>(current) + skip); \ |
| emit_write_barrier = (space_number == NEW_SPACE); \ |
| new_object = GetBackReferencedObject(data & kSpaceMask); \ |
| } else if (where == kRootArray) { \ |
| int id = source_.GetInt(); \ |
| Heap::RootListIndex root_index = static_cast<Heap::RootListIndex>(id); \ |
| new_object = isolate->heap()->root(root_index); \ |
| emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ |
| hot_objects_.Add(HeapObject::cast(new_object)); \ |
| } else if (where == kPartialSnapshotCache) { \ |
| int cache_index = source_.GetInt(); \ |
| new_object = isolate->partial_snapshot_cache()->at(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_table_->address(reference_id); \ |
| new_object = reinterpret_cast<Object*>(address); \ |
| } else if (where == kAttachedReference) { \ |
| int index = source_.GetInt(); \ |
| new_object = *attached_objects_[index]; \ |
| emit_write_barrier = isolate->heap()->InNewSpace(new_object); \ |
| } else { \ |
| DCHECK(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; \ |
| } \ |
| if (within == kInnerPointer) { \ |
| if (new_object->IsCode()) { \ |
| Code* new_code_object = Code::cast(new_object); \ |
| new_object = \ |
| reinterpret_cast<Object*>(new_code_object->instruction_start()); \ |
| } else { \ |
| 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( \ |
| isolate, 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 { \ |
| UnalignedCopy(current, &new_object); \ |
| } \ |
| } \ |
| if (emit_write_barrier && write_barrier_needed) { \ |
| Address current_address = reinterpret_cast<Address>(current); \ |
| SLOW_DCHECK(isolate->heap()->ContainsSlow(current_object_address)); \ |
| isolate->heap()->RecordWrite( \ |
| HeapObject::FromAddress(current_object_address), \ |
| static_cast<int>(current_address - current_object_address), \ |
| *reinterpret_cast<Object**>(current_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 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_SPACE) \ |
| CASE_STATEMENT(where, how, within, CODE_SPACE) \ |
| CASE_STATEMENT(where, how, within, MAP_SPACE) \ |
| CASE_STATEMENT(where, how, within, LO_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 SINGLE_CASE(where, how, within, space) \ |
| CASE_STATEMENT(where, how, within, space) \ |
| CASE_BODY(where, how, within, space) |
| |
| // 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. |
| SINGLE_CASE(kNewObject, kPlain, kInnerPointer, CODE_SPACE) |
| // Support for pointers into a cell. It's an inner pointer because it |
| // points directly at the value field, not the start of the cell object. |
| SINGLE_CASE(kNewObject, kPlain, kInnerPointer, OLD_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 V8_CODE_EMBEDS_OBJECT_POINTER |
| // Deserialize a new object from pointer found in code and write |
| // a pointer to it to the current object. Required only for MIPS, PPC, ARM |
| // or S390 with embedded 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, PPC, ARM or S390 with embedded |
| // 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) |
| // Support for direct instruction pointers in functions. |
| SINGLE_CASE(kBackref, kPlain, kInnerPointer, CODE_SPACE) |
| SINGLE_CASE(kBackrefWithSkip, kPlain, kInnerPointer, CODE_SPACE) |
| // Support for pointers into a cell. |
| SINGLE_CASE(kBackref, kPlain, kInnerPointer, OLD_SPACE) |
| SINGLE_CASE(kBackrefWithSkip, kPlain, kInnerPointer, OLD_SPACE) |
| // Find an object in the roots array and write a pointer to it to the |
| // current object. |
| SINGLE_CASE(kRootArray, kPlain, kStartOfObject, 0) |
| #if V8_CODE_EMBEDS_OBJECT_POINTER |
| // Find an object in the roots array and write a pointer to it to in code. |
| SINGLE_CASE(kRootArray, kFromCode, kStartOfObject, 0) |
| #endif |
| // Find an object in the partial snapshots cache and write a pointer to it |
| // to the current object. |
| SINGLE_CASE(kPartialSnapshotCache, kPlain, kStartOfObject, 0) |
| // Find an code entry in the partial snapshots cache and |
| // write a pointer to it to the current object. |
| SINGLE_CASE(kPartialSnapshotCache, kPlain, kInnerPointer, 0) |
| // Find an external reference and write a pointer to it to the current |
| // object. |
| SINGLE_CASE(kExternalReference, kPlain, kStartOfObject, 0) |
| // Find an external reference and write a pointer to it in the current |
| // code object. |
| SINGLE_CASE(kExternalReference, kFromCode, kStartOfObject, 0) |
| // Find an object in the attached references and write a pointer to it to |
| // the current object. |
| SINGLE_CASE(kAttachedReference, kPlain, kStartOfObject, 0) |
| SINGLE_CASE(kAttachedReference, kPlain, kInnerPointer, 0) |
| SINGLE_CASE(kAttachedReference, kFromCode, kInnerPointer, 0) |
| // Find a builtin and write a pointer to it to the current object. |
| SINGLE_CASE(kBuiltin, kPlain, kStartOfObject, 0) |
| SINGLE_CASE(kBuiltin, kPlain, kInnerPointer, 0) |
| SINGLE_CASE(kBuiltin, 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 kInternalReferenceEncoded: |
| case kInternalReference: { |
| // Internal reference address is not encoded via skip, but by offset |
| // from code entry. |
| int pc_offset = source_.GetInt(); |
| int target_offset = source_.GetInt(); |
| Code* code = |
| Code::cast(HeapObject::FromAddress(current_object_address)); |
| DCHECK(0 <= pc_offset && pc_offset <= code->instruction_size()); |
| DCHECK(0 <= target_offset && target_offset <= code->instruction_size()); |
| Address pc = code->entry() + pc_offset; |
| Address target = code->entry() + target_offset; |
| Assembler::deserialization_set_target_internal_reference_at( |
| isolate, pc, target, data == kInternalReference |
| ? RelocInfo::INTERNAL_REFERENCE |
| : RelocInfo::INTERNAL_REFERENCE_ENCODED); |
| break; |
| } |
| |
| case kNop: |
| break; |
| |
| case kNextChunk: { |
| int space = source_.Get(); |
| DCHECK(space < kNumberOfPreallocatedSpaces); |
| int chunk_index = current_chunk_[space]; |
| const Heap::Reservation& reservation = reservations_[space]; |
| // Make sure the current chunk is indeed exhausted. |
| CHECK_EQ(reservation[chunk_index].end, high_water_[space]); |
| // Move to next reserved chunk. |
| chunk_index = ++current_chunk_[space]; |
| CHECK_LT(chunk_index, reservation.length()); |
| high_water_[space] = reservation[chunk_index].start; |
| break; |
| } |
| |
| case kDeferred: { |
| // Deferred can only occur right after the heap object header. |
| DCHECK(current == reinterpret_cast<Object**>(current_object_address + |
| kPointerSize)); |
| HeapObject* obj = HeapObject::FromAddress(current_object_address); |
| // If the deferred object is a map, its instance type may be used |
| // during deserialization. Initialize it with a temporary value. |
| if (obj->IsMap()) Map::cast(obj)->set_instance_type(FILLER_TYPE); |
| current = limit; |
| return false; |
| } |
| |
| case kSynchronize: |
| // If we get here then that indicates that you have a mismatch between |
| // the number of GC roots when serializing and deserializing. |
| CHECK(false); |
| break; |
| |
| case kNativesStringResource: |
| current = CopyInNativesSource(Natives::GetScriptSource(source_.Get()), |
| current); |
| break; |
| |
| case kExtraNativesStringResource: |
| current = CopyInNativesSource( |
| ExtraNatives::GetScriptSource(source_.Get()), current); |
| break; |
| |
| // Deserialize raw data of variable length. |
| case kVariableRawData: { |
| int size_in_bytes = source_.GetInt(); |
| byte* raw_data_out = reinterpret_cast<byte*>(current); |
| source_.CopyRaw(raw_data_out, size_in_bytes); |
| break; |
| } |
| |
| case kVariableRepeat: { |
| int repeats = source_.GetInt(); |
| Object* object = current[-1]; |
| DCHECK(!isolate->heap()->InNewSpace(object)); |
| for (int i = 0; i < repeats; i++) UnalignedCopy(current++, &object); |
| break; |
| } |
| |
| case kAlignmentPrefix: |
| case kAlignmentPrefix + 1: |
| case kAlignmentPrefix + 2: |
| SetAlignment(data); |
| break; |
| |
| STATIC_ASSERT(kNumberOfRootArrayConstants == Heap::kOldSpaceRoots); |
| STATIC_ASSERT(kNumberOfRootArrayConstants == 32); |
| SIXTEEN_CASES(kRootArrayConstantsWithSkip) |
| SIXTEEN_CASES(kRootArrayConstantsWithSkip + 16) { |
| int skip = source_.GetInt(); |
| current = reinterpret_cast<Object**>( |
| reinterpret_cast<intptr_t>(current) + skip); |
| // Fall through. |
| } |
| |
| SIXTEEN_CASES(kRootArrayConstants) |
| SIXTEEN_CASES(kRootArrayConstants + 16) { |
| int id = data & kRootArrayConstantsMask; |
| Heap::RootListIndex root_index = static_cast<Heap::RootListIndex>(id); |
| Object* object = isolate->heap()->root(root_index); |
| DCHECK(!isolate->heap()->InNewSpace(object)); |
| UnalignedCopy(current++, &object); |
| break; |
| } |
| |
| STATIC_ASSERT(kNumberOfHotObjects == 8); |
| FOUR_CASES(kHotObjectWithSkip) |
| FOUR_CASES(kHotObjectWithSkip + 4) { |
| int skip = source_.GetInt(); |
| current = reinterpret_cast<Object**>( |
| reinterpret_cast<Address>(current) + skip); |
| // Fall through. |
| } |
| |
| FOUR_CASES(kHotObject) |
| FOUR_CASES(kHotObject + 4) { |
| int index = data & kHotObjectMask; |
| Object* hot_object = hot_objects_.Get(index); |
| UnalignedCopy(current, &hot_object); |
| if (write_barrier_needed && isolate->heap()->InNewSpace(hot_object)) { |
| Address current_address = reinterpret_cast<Address>(current); |
| isolate->heap()->RecordWrite( |
| HeapObject::FromAddress(current_object_address), |
| static_cast<int>(current_address - current_object_address), |
| hot_object); |
| } |
| current++; |
| break; |
| } |
| |
| // Deserialize raw data of fixed length from 1 to 32 words. |
| STATIC_ASSERT(kNumberOfFixedRawData == 32); |
| SIXTEEN_CASES(kFixedRawData) |
| SIXTEEN_CASES(kFixedRawData + 16) { |
| byte* raw_data_out = reinterpret_cast<byte*>(current); |
| int size_in_bytes = (data - kFixedRawDataStart) << kPointerSizeLog2; |
| source_.CopyRaw(raw_data_out, size_in_bytes); |
| current = reinterpret_cast<Object**>(raw_data_out + size_in_bytes); |
| break; |
| } |
| |
| STATIC_ASSERT(kNumberOfFixedRepeat == 16); |
| SIXTEEN_CASES(kFixedRepeat) { |
| int repeats = data - kFixedRepeatStart; |
| Object* object; |
| UnalignedCopy(&object, current - 1); |
| DCHECK(!isolate->heap()->InNewSpace(object)); |
| for (int i = 0; i < repeats; i++) UnalignedCopy(current++, &object); |
| break; |
| } |
| |
| #undef SIXTEEN_CASES |
| #undef FOUR_CASES |
| #undef SINGLE_CASE |
| |
| default: |
| CHECK(false); |
| } |
| } |
| CHECK_EQ(limit, current); |
| return true; |
| } |
| } // namespace internal |
| } // namespace v8 |