// Copyright 2013 the V8 project authors. All rights reserved. // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following // disclaimer in the documentation and/or other materials provided // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. #include "v8.h" #include "heap-snapshot-generator-inl.h" #include "heap-profiler.h" #include "debug.h" #include "types.h" namespace v8 { namespace internal { HeapGraphEdge::HeapGraphEdge(Type type, const char* name, int from, int to) : type_(type), from_index_(from), to_index_(to), name_(name) { ASSERT(type == kContextVariable || type == kProperty || type == kInternal || type == kShortcut); } HeapGraphEdge::HeapGraphEdge(Type type, int index, int from, int to) : type_(type), from_index_(from), to_index_(to), index_(index) { ASSERT(type == kElement || type == kHidden || type == kWeak); } void HeapGraphEdge::ReplaceToIndexWithEntry(HeapSnapshot* snapshot) { to_entry_ = &snapshot->entries()[to_index_]; } const int HeapEntry::kNoEntry = -1; HeapEntry::HeapEntry(HeapSnapshot* snapshot, Type type, const char* name, SnapshotObjectId id, int self_size) : type_(type), children_count_(0), children_index_(-1), self_size_(self_size), id_(id), snapshot_(snapshot), name_(name) { } void HeapEntry::SetNamedReference(HeapGraphEdge::Type type, const char* name, HeapEntry* entry) { HeapGraphEdge edge(type, name, this->index(), entry->index()); snapshot_->edges().Add(edge); ++children_count_; } void HeapEntry::SetIndexedReference(HeapGraphEdge::Type type, int index, HeapEntry* entry) { HeapGraphEdge edge(type, index, this->index(), entry->index()); snapshot_->edges().Add(edge); ++children_count_; } Handle HeapEntry::GetHeapObject() { return snapshot_->collection()->FindHeapObjectById(id()); } void HeapEntry::Print( const char* prefix, const char* edge_name, int max_depth, int indent) { STATIC_CHECK(sizeof(unsigned) == sizeof(id())); OS::Print("%6d @%6u %*c %s%s: ", self_size(), id(), indent, ' ', prefix, edge_name); if (type() != kString) { OS::Print("%s %.40s\n", TypeAsString(), name_); } else { OS::Print("\""); const char* c = name_; while (*c && (c - name_) <= 40) { if (*c != '\n') OS::Print("%c", *c); else OS::Print("\\n"); ++c; } OS::Print("\"\n"); } if (--max_depth == 0) return; Vector ch = children(); for (int i = 0; i < ch.length(); ++i) { HeapGraphEdge& edge = *ch[i]; const char* edge_prefix = ""; EmbeddedVector index; const char* edge_name = index.start(); switch (edge.type()) { case HeapGraphEdge::kContextVariable: edge_prefix = "#"; edge_name = edge.name(); break; case HeapGraphEdge::kElement: OS::SNPrintF(index, "%d", edge.index()); break; case HeapGraphEdge::kInternal: edge_prefix = "$"; edge_name = edge.name(); break; case HeapGraphEdge::kProperty: edge_name = edge.name(); break; case HeapGraphEdge::kHidden: edge_prefix = "$"; OS::SNPrintF(index, "%d", edge.index()); break; case HeapGraphEdge::kShortcut: edge_prefix = "^"; edge_name = edge.name(); break; case HeapGraphEdge::kWeak: edge_prefix = "w"; OS::SNPrintF(index, "%d", edge.index()); break; default: OS::SNPrintF(index, "!!! unknown edge type: %d ", edge.type()); } edge.to()->Print(edge_prefix, edge_name, max_depth, indent + 2); } } const char* HeapEntry::TypeAsString() { switch (type()) { case kHidden: return "/hidden/"; case kObject: return "/object/"; case kClosure: return "/closure/"; case kString: return "/string/"; case kCode: return "/code/"; case kArray: return "/array/"; case kRegExp: return "/regexp/"; case kHeapNumber: return "/number/"; case kNative: return "/native/"; case kSynthetic: return "/synthetic/"; default: return "???"; } } // It is very important to keep objects that form a heap snapshot // as small as possible. namespace { // Avoid littering the global namespace. template struct SnapshotSizeConstants; template <> struct SnapshotSizeConstants<4> { static const int kExpectedHeapGraphEdgeSize = 12; static const int kExpectedHeapEntrySize = 24; }; template <> struct SnapshotSizeConstants<8> { static const int kExpectedHeapGraphEdgeSize = 24; static const int kExpectedHeapEntrySize = 32; }; } // namespace HeapSnapshot::HeapSnapshot(HeapSnapshotsCollection* collection, const char* title, unsigned uid) : collection_(collection), title_(title), uid_(uid), root_index_(HeapEntry::kNoEntry), gc_roots_index_(HeapEntry::kNoEntry), natives_root_index_(HeapEntry::kNoEntry), max_snapshot_js_object_id_(0) { STATIC_CHECK( sizeof(HeapGraphEdge) == SnapshotSizeConstants::kExpectedHeapGraphEdgeSize); STATIC_CHECK( sizeof(HeapEntry) == SnapshotSizeConstants::kExpectedHeapEntrySize); for (int i = 0; i < VisitorSynchronization::kNumberOfSyncTags; ++i) { gc_subroot_indexes_[i] = HeapEntry::kNoEntry; } } void HeapSnapshot::Delete() { collection_->RemoveSnapshot(this); delete this; } void HeapSnapshot::RememberLastJSObjectId() { max_snapshot_js_object_id_ = collection_->last_assigned_id(); } HeapEntry* HeapSnapshot::AddRootEntry() { ASSERT(root_index_ == HeapEntry::kNoEntry); ASSERT(entries_.is_empty()); // Root entry must be the first one. HeapEntry* entry = AddEntry(HeapEntry::kSynthetic, "", HeapObjectsMap::kInternalRootObjectId, 0); root_index_ = entry->index(); ASSERT(root_index_ == 0); return entry; } HeapEntry* HeapSnapshot::AddGcRootsEntry() { ASSERT(gc_roots_index_ == HeapEntry::kNoEntry); HeapEntry* entry = AddEntry(HeapEntry::kSynthetic, "(GC roots)", HeapObjectsMap::kGcRootsObjectId, 0); gc_roots_index_ = entry->index(); return entry; } HeapEntry* HeapSnapshot::AddGcSubrootEntry(int tag) { ASSERT(gc_subroot_indexes_[tag] == HeapEntry::kNoEntry); ASSERT(0 <= tag && tag < VisitorSynchronization::kNumberOfSyncTags); HeapEntry* entry = AddEntry( HeapEntry::kSynthetic, VisitorSynchronization::kTagNames[tag], HeapObjectsMap::GetNthGcSubrootId(tag), 0); gc_subroot_indexes_[tag] = entry->index(); return entry; } HeapEntry* HeapSnapshot::AddEntry(HeapEntry::Type type, const char* name, SnapshotObjectId id, int size) { HeapEntry entry(this, type, name, id, size); entries_.Add(entry); return &entries_.last(); } void HeapSnapshot::FillChildren() { ASSERT(children().is_empty()); children().Allocate(edges().length()); int children_index = 0; for (int i = 0; i < entries().length(); ++i) { HeapEntry* entry = &entries()[i]; children_index = entry->set_children_index(children_index); } ASSERT(edges().length() == children_index); for (int i = 0; i < edges().length(); ++i) { HeapGraphEdge* edge = &edges()[i]; edge->ReplaceToIndexWithEntry(this); edge->from()->add_child(edge); } } class FindEntryById { public: explicit FindEntryById(SnapshotObjectId id) : id_(id) { } int operator()(HeapEntry* const* entry) { if ((*entry)->id() == id_) return 0; return (*entry)->id() < id_ ? -1 : 1; } private: SnapshotObjectId id_; }; HeapEntry* HeapSnapshot::GetEntryById(SnapshotObjectId id) { List* entries_by_id = GetSortedEntriesList(); // Perform a binary search by id. int index = SortedListBSearch(*entries_by_id, FindEntryById(id)); if (index == -1) return NULL; return entries_by_id->at(index); } template static int SortByIds(const T* entry1_ptr, const T* entry2_ptr) { if ((*entry1_ptr)->id() == (*entry2_ptr)->id()) return 0; return (*entry1_ptr)->id() < (*entry2_ptr)->id() ? -1 : 1; } List* HeapSnapshot::GetSortedEntriesList() { if (sorted_entries_.is_empty()) { sorted_entries_.Allocate(entries_.length()); for (int i = 0; i < entries_.length(); ++i) { sorted_entries_[i] = &entries_[i]; } sorted_entries_.Sort(SortByIds); } return &sorted_entries_; } void HeapSnapshot::Print(int max_depth) { root()->Print("", "", max_depth, 0); } template static size_t GetMemoryUsedByList(const List& list) { return list.length() * sizeof(T) + sizeof(list); } size_t HeapSnapshot::RawSnapshotSize() const { return sizeof(*this) + GetMemoryUsedByList(entries_) + GetMemoryUsedByList(edges_) + GetMemoryUsedByList(children_) + GetMemoryUsedByList(sorted_entries_); } // We split IDs on evens for embedder objects (see // HeapObjectsMap::GenerateId) and odds for native objects. const SnapshotObjectId HeapObjectsMap::kInternalRootObjectId = 1; const SnapshotObjectId HeapObjectsMap::kGcRootsObjectId = HeapObjectsMap::kInternalRootObjectId + HeapObjectsMap::kObjectIdStep; const SnapshotObjectId HeapObjectsMap::kGcRootsFirstSubrootId = HeapObjectsMap::kGcRootsObjectId + HeapObjectsMap::kObjectIdStep; const SnapshotObjectId HeapObjectsMap::kFirstAvailableObjectId = HeapObjectsMap::kGcRootsFirstSubrootId + VisitorSynchronization::kNumberOfSyncTags * HeapObjectsMap::kObjectIdStep; HeapObjectsMap::HeapObjectsMap(Heap* heap) : next_id_(kFirstAvailableObjectId), entries_map_(AddressesMatch), heap_(heap) { // This dummy element solves a problem with entries_map_. // When we do lookup in HashMap we see no difference between two cases: // it has an entry with NULL as the value or it has created // a new entry on the fly with NULL as the default value. // With such dummy element we have a guaranty that all entries_map_ entries // will have the value field grater than 0. // This fact is using in MoveObject method. entries_.Add(EntryInfo(0, NULL, 0)); } void HeapObjectsMap::SnapshotGenerationFinished() { RemoveDeadEntries(); } void HeapObjectsMap::MoveObject(Address from, Address to) { ASSERT(to != NULL); ASSERT(from != NULL); if (from == to) return; void* from_value = entries_map_.Remove(from, AddressHash(from)); if (from_value == NULL) { // It may occur that some untracked object moves to an address X and there // is a tracked object at that address. In this case we should remove the // entry as we know that the object has died. void* to_value = entries_map_.Remove(to, AddressHash(to)); if (to_value != NULL) { int to_entry_info_index = static_cast(reinterpret_cast(to_value)); entries_.at(to_entry_info_index).addr = NULL; } } else { HashMap::Entry* to_entry = entries_map_.Lookup(to, AddressHash(to), true); if (to_entry->value != NULL) { // We found the existing entry with to address for an old object. // Without this operation we will have two EntryInfo's with the same // value in addr field. It is bad because later at RemoveDeadEntries // one of this entry will be removed with the corresponding entries_map_ // entry. int to_entry_info_index = static_cast(reinterpret_cast(to_entry->value)); entries_.at(to_entry_info_index).addr = NULL; } int from_entry_info_index = static_cast(reinterpret_cast(from_value)); entries_.at(from_entry_info_index).addr = to; to_entry->value = from_value; } } SnapshotObjectId HeapObjectsMap::FindEntry(Address addr) { HashMap::Entry* entry = entries_map_.Lookup(addr, AddressHash(addr), false); if (entry == NULL) return 0; int entry_index = static_cast(reinterpret_cast(entry->value)); EntryInfo& entry_info = entries_.at(entry_index); ASSERT(static_cast(entries_.length()) > entries_map_.occupancy()); return entry_info.id; } SnapshotObjectId HeapObjectsMap::FindOrAddEntry(Address addr, unsigned int size) { ASSERT(static_cast(entries_.length()) > entries_map_.occupancy()); HashMap::Entry* entry = entries_map_.Lookup(addr, AddressHash(addr), true); if (entry->value != NULL) { int entry_index = static_cast(reinterpret_cast(entry->value)); EntryInfo& entry_info = entries_.at(entry_index); entry_info.accessed = true; entry_info.size = size; return entry_info.id; } entry->value = reinterpret_cast(entries_.length()); SnapshotObjectId id = next_id_; next_id_ += kObjectIdStep; entries_.Add(EntryInfo(id, addr, size)); ASSERT(static_cast(entries_.length()) > entries_map_.occupancy()); return id; } void HeapObjectsMap::StopHeapObjectsTracking() { time_intervals_.Clear(); } void HeapObjectsMap::UpdateHeapObjectsMap() { HEAP->CollectAllGarbage(Heap::kMakeHeapIterableMask, "HeapSnapshotsCollection::UpdateHeapObjectsMap"); HeapIterator iterator(heap_); for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next()) { FindOrAddEntry(obj->address(), obj->Size()); } RemoveDeadEntries(); } SnapshotObjectId HeapObjectsMap::PushHeapObjectsStats(OutputStream* stream) { UpdateHeapObjectsMap(); time_intervals_.Add(TimeInterval(next_id_)); int prefered_chunk_size = stream->GetChunkSize(); List stats_buffer; ASSERT(!entries_.is_empty()); EntryInfo* entry_info = &entries_.first(); EntryInfo* end_entry_info = &entries_.last() + 1; for (int time_interval_index = 0; time_interval_index < time_intervals_.length(); ++time_interval_index) { TimeInterval& time_interval = time_intervals_[time_interval_index]; SnapshotObjectId time_interval_id = time_interval.id; uint32_t entries_size = 0; EntryInfo* start_entry_info = entry_info; while (entry_info < end_entry_info && entry_info->id < time_interval_id) { entries_size += entry_info->size; ++entry_info; } uint32_t entries_count = static_cast(entry_info - start_entry_info); if (time_interval.count != entries_count || time_interval.size != entries_size) { stats_buffer.Add(v8::HeapStatsUpdate( time_interval_index, time_interval.count = entries_count, time_interval.size = entries_size)); if (stats_buffer.length() >= prefered_chunk_size) { OutputStream::WriteResult result = stream->WriteHeapStatsChunk( &stats_buffer.first(), stats_buffer.length()); if (result == OutputStream::kAbort) return last_assigned_id(); stats_buffer.Clear(); } } } ASSERT(entry_info == end_entry_info); if (!stats_buffer.is_empty()) { OutputStream::WriteResult result = stream->WriteHeapStatsChunk( &stats_buffer.first(), stats_buffer.length()); if (result == OutputStream::kAbort) return last_assigned_id(); } stream->EndOfStream(); return last_assigned_id(); } void HeapObjectsMap::RemoveDeadEntries() { ASSERT(entries_.length() > 0 && entries_.at(0).id == 0 && entries_.at(0).addr == NULL); int first_free_entry = 1; for (int i = 1; i < entries_.length(); ++i) { EntryInfo& entry_info = entries_.at(i); if (entry_info.accessed) { if (first_free_entry != i) { entries_.at(first_free_entry) = entry_info; } entries_.at(first_free_entry).accessed = false; HashMap::Entry* entry = entries_map_.Lookup( entry_info.addr, AddressHash(entry_info.addr), false); ASSERT(entry); entry->value = reinterpret_cast(first_free_entry); ++first_free_entry; } else { if (entry_info.addr) { entries_map_.Remove(entry_info.addr, AddressHash(entry_info.addr)); } } } entries_.Rewind(first_free_entry); ASSERT(static_cast(entries_.length()) - 1 == entries_map_.occupancy()); } SnapshotObjectId HeapObjectsMap::GenerateId(v8::RetainedObjectInfo* info) { SnapshotObjectId id = static_cast(info->GetHash()); const char* label = info->GetLabel(); id ^= StringHasher::HashSequentialString(label, static_cast(strlen(label)), HEAP->HashSeed()); intptr_t element_count = info->GetElementCount(); if (element_count != -1) id ^= ComputeIntegerHash(static_cast(element_count), v8::internal::kZeroHashSeed); return id << 1; } size_t HeapObjectsMap::GetUsedMemorySize() const { return sizeof(*this) + sizeof(HashMap::Entry) * entries_map_.capacity() + GetMemoryUsedByList(entries_) + GetMemoryUsedByList(time_intervals_); } HeapSnapshotsCollection::HeapSnapshotsCollection(Heap* heap) : is_tracking_objects_(false), ids_(heap) { } static void DeleteHeapSnapshot(HeapSnapshot** snapshot_ptr) { delete *snapshot_ptr; } HeapSnapshotsCollection::~HeapSnapshotsCollection() { snapshots_.Iterate(DeleteHeapSnapshot); } HeapSnapshot* HeapSnapshotsCollection::NewSnapshot(const char* name, unsigned uid) { is_tracking_objects_ = true; // Start watching for heap objects moves. return new HeapSnapshot(this, name, uid); } void HeapSnapshotsCollection::SnapshotGenerationFinished( HeapSnapshot* snapshot) { ids_.SnapshotGenerationFinished(); if (snapshot != NULL) { snapshots_.Add(snapshot); } } void HeapSnapshotsCollection::RemoveSnapshot(HeapSnapshot* snapshot) { snapshots_.RemoveElement(snapshot); } Handle HeapSnapshotsCollection::FindHeapObjectById( SnapshotObjectId id) { // First perform a full GC in order to avoid dead objects. HEAP->CollectAllGarbage(Heap::kMakeHeapIterableMask, "HeapSnapshotsCollection::FindHeapObjectById"); DisallowHeapAllocation no_allocation; HeapObject* object = NULL; HeapIterator iterator(heap(), HeapIterator::kFilterUnreachable); // Make sure that object with the given id is still reachable. for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next()) { if (ids_.FindEntry(obj->address()) == id) { ASSERT(object == NULL); object = obj; // Can't break -- kFilterUnreachable requires full heap traversal. } } return object != NULL ? Handle(object) : Handle(); } size_t HeapSnapshotsCollection::GetUsedMemorySize() const { size_t size = sizeof(*this); size += names_.GetUsedMemorySize(); size += ids_.GetUsedMemorySize(); size += GetMemoryUsedByList(snapshots_); for (int i = 0; i < snapshots_.length(); ++i) { size += snapshots_[i]->RawSnapshotSize(); } return size; } HeapEntriesMap::HeapEntriesMap() : entries_(HeapThingsMatch) { } int HeapEntriesMap::Map(HeapThing thing) { HashMap::Entry* cache_entry = entries_.Lookup(thing, Hash(thing), false); if (cache_entry == NULL) return HeapEntry::kNoEntry; return static_cast(reinterpret_cast(cache_entry->value)); } void HeapEntriesMap::Pair(HeapThing thing, int entry) { HashMap::Entry* cache_entry = entries_.Lookup(thing, Hash(thing), true); ASSERT(cache_entry->value == NULL); cache_entry->value = reinterpret_cast(static_cast(entry)); } HeapObjectsSet::HeapObjectsSet() : entries_(HeapEntriesMap::HeapThingsMatch) { } void HeapObjectsSet::Clear() { entries_.Clear(); } bool HeapObjectsSet::Contains(Object* obj) { if (!obj->IsHeapObject()) return false; HeapObject* object = HeapObject::cast(obj); return entries_.Lookup(object, HeapEntriesMap::Hash(object), false) != NULL; } void HeapObjectsSet::Insert(Object* obj) { if (!obj->IsHeapObject()) return; HeapObject* object = HeapObject::cast(obj); entries_.Lookup(object, HeapEntriesMap::Hash(object), true); } const char* HeapObjectsSet::GetTag(Object* obj) { HeapObject* object = HeapObject::cast(obj); HashMap::Entry* cache_entry = entries_.Lookup(object, HeapEntriesMap::Hash(object), false); return cache_entry != NULL ? reinterpret_cast(cache_entry->value) : NULL; } void HeapObjectsSet::SetTag(Object* obj, const char* tag) { if (!obj->IsHeapObject()) return; HeapObject* object = HeapObject::cast(obj); HashMap::Entry* cache_entry = entries_.Lookup(object, HeapEntriesMap::Hash(object), true); cache_entry->value = const_cast(tag); } HeapObject* const V8HeapExplorer::kInternalRootObject = reinterpret_cast( static_cast(HeapObjectsMap::kInternalRootObjectId)); HeapObject* const V8HeapExplorer::kGcRootsObject = reinterpret_cast( static_cast(HeapObjectsMap::kGcRootsObjectId)); HeapObject* const V8HeapExplorer::kFirstGcSubrootObject = reinterpret_cast( static_cast(HeapObjectsMap::kGcRootsFirstSubrootId)); HeapObject* const V8HeapExplorer::kLastGcSubrootObject = reinterpret_cast( static_cast(HeapObjectsMap::kFirstAvailableObjectId)); V8HeapExplorer::V8HeapExplorer( HeapSnapshot* snapshot, SnapshottingProgressReportingInterface* progress, v8::HeapProfiler::ObjectNameResolver* resolver) : heap_(Isolate::Current()->heap()), snapshot_(snapshot), collection_(snapshot_->collection()), progress_(progress), filler_(NULL), global_object_name_resolver_(resolver) { } V8HeapExplorer::~V8HeapExplorer() { } HeapEntry* V8HeapExplorer::AllocateEntry(HeapThing ptr) { return AddEntry(reinterpret_cast(ptr)); } HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object) { if (object == kInternalRootObject) { snapshot_->AddRootEntry(); return snapshot_->root(); } else if (object == kGcRootsObject) { HeapEntry* entry = snapshot_->AddGcRootsEntry(); return entry; } else if (object >= kFirstGcSubrootObject && object < kLastGcSubrootObject) { HeapEntry* entry = snapshot_->AddGcSubrootEntry(GetGcSubrootOrder(object)); return entry; } else if (object->IsJSFunction()) { JSFunction* func = JSFunction::cast(object); SharedFunctionInfo* shared = func->shared(); const char* name = shared->bound() ? "native_bind" : collection_->names()->GetName(String::cast(shared->name())); return AddEntry(object, HeapEntry::kClosure, name); } else if (object->IsJSRegExp()) { JSRegExp* re = JSRegExp::cast(object); return AddEntry(object, HeapEntry::kRegExp, collection_->names()->GetName(re->Pattern())); } else if (object->IsJSObject()) { const char* name = collection_->names()->GetName( GetConstructorName(JSObject::cast(object))); if (object->IsJSGlobalObject()) { const char* tag = objects_tags_.GetTag(object); if (tag != NULL) { name = collection_->names()->GetFormatted("%s / %s", name, tag); } } return AddEntry(object, HeapEntry::kObject, name); } else if (object->IsString()) { return AddEntry(object, HeapEntry::kString, collection_->names()->GetName(String::cast(object))); } else if (object->IsCode()) { return AddEntry(object, HeapEntry::kCode, ""); } else if (object->IsSharedFunctionInfo()) { String* name = String::cast(SharedFunctionInfo::cast(object)->name()); return AddEntry(object, HeapEntry::kCode, collection_->names()->GetName(name)); } else if (object->IsScript()) { Object* name = Script::cast(object)->name(); return AddEntry(object, HeapEntry::kCode, name->IsString() ? collection_->names()->GetName(String::cast(name)) : ""); } else if (object->IsNativeContext()) { return AddEntry(object, HeapEntry::kHidden, "system / NativeContext"); } else if (object->IsContext()) { return AddEntry(object, HeapEntry::kObject, "system / Context"); } else if (object->IsFixedArray() || object->IsFixedDoubleArray() || object->IsByteArray() || object->IsExternalArray()) { return AddEntry(object, HeapEntry::kArray, ""); } else if (object->IsHeapNumber()) { return AddEntry(object, HeapEntry::kHeapNumber, "number"); } return AddEntry(object, HeapEntry::kHidden, GetSystemEntryName(object)); } HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object, HeapEntry::Type type, const char* name) { int object_size = object->Size(); SnapshotObjectId object_id = collection_->GetObjectId(object->address(), object_size); return snapshot_->AddEntry(type, name, object_id, object_size); } class GcSubrootsEnumerator : public ObjectVisitor { public: GcSubrootsEnumerator( SnapshotFillerInterface* filler, V8HeapExplorer* explorer) : filler_(filler), explorer_(explorer), previous_object_count_(0), object_count_(0) { } void VisitPointers(Object** start, Object** end) { object_count_ += end - start; } void Synchronize(VisitorSynchronization::SyncTag tag) { // Skip empty subroots. if (previous_object_count_ != object_count_) { previous_object_count_ = object_count_; filler_->AddEntry(V8HeapExplorer::GetNthGcSubrootObject(tag), explorer_); } } private: SnapshotFillerInterface* filler_; V8HeapExplorer* explorer_; intptr_t previous_object_count_; intptr_t object_count_; }; void V8HeapExplorer::AddRootEntries(SnapshotFillerInterface* filler) { filler->AddEntry(kInternalRootObject, this); filler->AddEntry(kGcRootsObject, this); GcSubrootsEnumerator enumerator(filler, this); heap_->IterateRoots(&enumerator, VISIT_ALL); } const char* V8HeapExplorer::GetSystemEntryName(HeapObject* object) { switch (object->map()->instance_type()) { case MAP_TYPE: switch (Map::cast(object)->instance_type()) { #define MAKE_STRING_MAP_CASE(instance_type, size, name, Name) \ case instance_type: return "system / Map (" #Name ")"; STRING_TYPE_LIST(MAKE_STRING_MAP_CASE) #undef MAKE_STRING_MAP_CASE default: return "system / Map"; } case CELL_TYPE: return "system / Cell"; case PROPERTY_CELL_TYPE: return "system / PropertyCell"; case FOREIGN_TYPE: return "system / Foreign"; case ODDBALL_TYPE: return "system / Oddball"; #define MAKE_STRUCT_CASE(NAME, Name, name) \ case NAME##_TYPE: return "system / "#Name; STRUCT_LIST(MAKE_STRUCT_CASE) #undef MAKE_STRUCT_CASE default: return "system"; } } int V8HeapExplorer::EstimateObjectsCount(HeapIterator* iterator) { int objects_count = 0; for (HeapObject* obj = iterator->next(); obj != NULL; obj = iterator->next()) { objects_count++; } return objects_count; } class IndexedReferencesExtractor : public ObjectVisitor { public: IndexedReferencesExtractor(V8HeapExplorer* generator, HeapObject* parent_obj, int parent) : generator_(generator), parent_obj_(parent_obj), parent_(parent), next_index_(0) { } void VisitCodeEntry(Address entry_address) { Code* code = Code::cast(Code::GetObjectFromEntryAddress(entry_address)); generator_->SetInternalReference(parent_obj_, parent_, "code", code); generator_->TagObject(code, "(code)"); } void VisitPointers(Object** start, Object** end) { for (Object** p = start; p < end; p++) { if (CheckVisitedAndUnmark(p)) continue; generator_->SetHiddenReference(parent_obj_, parent_, next_index_++, *p); } } static void MarkVisitedField(HeapObject* obj, int offset) { if (offset < 0) return; Address field = obj->address() + offset; ASSERT(!Memory::Object_at(field)->IsFailure()); ASSERT(Memory::Object_at(field)->IsHeapObject()); *field |= kFailureTag; } private: bool CheckVisitedAndUnmark(Object** field) { if ((*field)->IsFailure()) { intptr_t untagged = reinterpret_cast(*field) & ~kFailureTagMask; *field = reinterpret_cast(untagged | kHeapObjectTag); ASSERT((*field)->IsHeapObject()); return true; } return false; } V8HeapExplorer* generator_; HeapObject* parent_obj_; int parent_; int next_index_; }; void V8HeapExplorer::ExtractReferences(HeapObject* obj) { HeapEntry* heap_entry = GetEntry(obj); if (heap_entry == NULL) return; // No interest in this object. int entry = heap_entry->index(); if (obj->IsJSGlobalProxy()) { ExtractJSGlobalProxyReferences(entry, JSGlobalProxy::cast(obj)); } else if (obj->IsJSObject()) { ExtractJSObjectReferences(entry, JSObject::cast(obj)); } else if (obj->IsString()) { ExtractStringReferences(entry, String::cast(obj)); } else if (obj->IsContext()) { ExtractContextReferences(entry, Context::cast(obj)); } else if (obj->IsMap()) { ExtractMapReferences(entry, Map::cast(obj)); } else if (obj->IsSharedFunctionInfo()) { ExtractSharedFunctionInfoReferences(entry, SharedFunctionInfo::cast(obj)); } else if (obj->IsScript()) { ExtractScriptReferences(entry, Script::cast(obj)); } else if (obj->IsAccessorPair()) { ExtractAccessorPairReferences(entry, AccessorPair::cast(obj)); } else if (obj->IsCodeCache()) { ExtractCodeCacheReferences(entry, CodeCache::cast(obj)); } else if (obj->IsCode()) { ExtractCodeReferences(entry, Code::cast(obj)); } else if (obj->IsCell()) { ExtractCellReferences(entry, Cell::cast(obj)); } else if (obj->IsPropertyCell()) { ExtractPropertyCellReferences(entry, PropertyCell::cast(obj)); } else if (obj->IsAllocationSite()) { ExtractAllocationSiteReferences(entry, AllocationSite::cast(obj)); } SetInternalReference(obj, entry, "map", obj->map(), HeapObject::kMapOffset); // Extract unvisited fields as hidden references and restore tags // of visited fields. IndexedReferencesExtractor refs_extractor(this, obj, entry); obj->Iterate(&refs_extractor); } void V8HeapExplorer::ExtractJSGlobalProxyReferences( int entry, JSGlobalProxy* proxy) { SetInternalReference(proxy, entry, "native_context", proxy->native_context(), JSGlobalProxy::kNativeContextOffset); } void V8HeapExplorer::ExtractJSObjectReferences( int entry, JSObject* js_obj) { HeapObject* obj = js_obj; ExtractClosureReferences(js_obj, entry); ExtractPropertyReferences(js_obj, entry); ExtractElementReferences(js_obj, entry); ExtractInternalReferences(js_obj, entry); SetPropertyReference( obj, entry, heap_->proto_string(), js_obj->GetPrototype()); if (obj->IsJSFunction()) { JSFunction* js_fun = JSFunction::cast(js_obj); Object* proto_or_map = js_fun->prototype_or_initial_map(); if (!proto_or_map->IsTheHole()) { if (!proto_or_map->IsMap()) { SetPropertyReference( obj, entry, heap_->prototype_string(), proto_or_map, NULL, JSFunction::kPrototypeOrInitialMapOffset); } else { SetPropertyReference( obj, entry, heap_->prototype_string(), js_fun->prototype()); SetInternalReference( obj, entry, "initial_map", proto_or_map, JSFunction::kPrototypeOrInitialMapOffset); } } SharedFunctionInfo* shared_info = js_fun->shared(); // JSFunction has either bindings or literals and never both. bool bound = shared_info->bound(); TagObject(js_fun->literals_or_bindings(), bound ? "(function bindings)" : "(function literals)"); SetInternalReference(js_fun, entry, bound ? "bindings" : "literals", js_fun->literals_or_bindings(), JSFunction::kLiteralsOffset); TagObject(shared_info, "(shared function info)"); SetInternalReference(js_fun, entry, "shared", shared_info, JSFunction::kSharedFunctionInfoOffset); TagObject(js_fun->context(), "(context)"); SetInternalReference(js_fun, entry, "context", js_fun->context(), JSFunction::kContextOffset); for (int i = JSFunction::kNonWeakFieldsEndOffset; i < JSFunction::kSize; i += kPointerSize) { SetWeakReference(js_fun, entry, i, *HeapObject::RawField(js_fun, i), i); } } else if (obj->IsGlobalObject()) { GlobalObject* global_obj = GlobalObject::cast(obj); SetInternalReference(global_obj, entry, "builtins", global_obj->builtins(), GlobalObject::kBuiltinsOffset); SetInternalReference(global_obj, entry, "native_context", global_obj->native_context(), GlobalObject::kNativeContextOffset); SetInternalReference(global_obj, entry, "global_receiver", global_obj->global_receiver(), GlobalObject::kGlobalReceiverOffset); } TagObject(js_obj->properties(), "(object properties)"); SetInternalReference(obj, entry, "properties", js_obj->properties(), JSObject::kPropertiesOffset); TagObject(js_obj->elements(), "(object elements)"); SetInternalReference(obj, entry, "elements", js_obj->elements(), JSObject::kElementsOffset); } void V8HeapExplorer::ExtractStringReferences(int entry, String* string) { if (string->IsConsString()) { ConsString* cs = ConsString::cast(string); SetInternalReference(cs, entry, "first", cs->first(), ConsString::kFirstOffset); SetInternalReference(cs, entry, "second", cs->second(), ConsString::kSecondOffset); } else if (string->IsSlicedString()) { SlicedString* ss = SlicedString::cast(string); SetInternalReference(ss, entry, "parent", ss->parent(), SlicedString::kParentOffset); } } void V8HeapExplorer::ExtractContextReferences(int entry, Context* context) { if (context == context->declaration_context()) { ScopeInfo* scope_info = context->closure()->shared()->scope_info(); // Add context allocated locals. int context_locals = scope_info->ContextLocalCount(); for (int i = 0; i < context_locals; ++i) { String* local_name = scope_info->ContextLocalName(i); int idx = Context::MIN_CONTEXT_SLOTS + i; SetContextReference(context, entry, local_name, context->get(idx), Context::OffsetOfElementAt(idx)); } if (scope_info->HasFunctionName()) { String* name = scope_info->FunctionName(); VariableMode mode; int idx = scope_info->FunctionContextSlotIndex(name, &mode); if (idx >= 0) { SetContextReference(context, entry, name, context->get(idx), Context::OffsetOfElementAt(idx)); } } } #define EXTRACT_CONTEXT_FIELD(index, type, name) \ SetInternalReference(context, entry, #name, context->get(Context::index), \ FixedArray::OffsetOfElementAt(Context::index)); EXTRACT_CONTEXT_FIELD(CLOSURE_INDEX, JSFunction, closure); EXTRACT_CONTEXT_FIELD(PREVIOUS_INDEX, Context, previous); EXTRACT_CONTEXT_FIELD(EXTENSION_INDEX, Object, extension); EXTRACT_CONTEXT_FIELD(GLOBAL_OBJECT_INDEX, GlobalObject, global); if (context->IsNativeContext()) { TagObject(context->jsfunction_result_caches(), "(context func. result caches)"); TagObject(context->normalized_map_cache(), "(context norm. map cache)"); TagObject(context->runtime_context(), "(runtime context)"); TagObject(context->embedder_data(), "(context data)"); NATIVE_CONTEXT_FIELDS(EXTRACT_CONTEXT_FIELD); #undef EXTRACT_CONTEXT_FIELD for (int i = Context::FIRST_WEAK_SLOT; i < Context::NATIVE_CONTEXT_SLOTS; ++i) { SetWeakReference(context, entry, i, context->get(i), FixedArray::OffsetOfElementAt(i)); } } } void V8HeapExplorer::ExtractMapReferences(int entry, Map* map) { if (map->HasTransitionArray()) { TransitionArray* transitions = map->transitions(); int transitions_entry = GetEntry(transitions)->index(); Object* back_pointer = transitions->back_pointer_storage(); TagObject(back_pointer, "(back pointer)"); SetInternalReference(transitions, transitions_entry, "back_pointer", back_pointer); TagObject(transitions, "(transition array)"); SetInternalReference(map, entry, "transitions", transitions, Map::kTransitionsOrBackPointerOffset); } else { Object* back_pointer = map->GetBackPointer(); TagObject(back_pointer, "(back pointer)"); SetInternalReference(map, entry, "back_pointer", back_pointer, Map::kTransitionsOrBackPointerOffset); } DescriptorArray* descriptors = map->instance_descriptors(); TagObject(descriptors, "(map descriptors)"); SetInternalReference(map, entry, "descriptors", descriptors, Map::kDescriptorsOffset); SetInternalReference(map, entry, "code_cache", map->code_cache(), Map::kCodeCacheOffset); SetInternalReference(map, entry, "prototype", map->prototype(), Map::kPrototypeOffset); SetInternalReference(map, entry, "constructor", map->constructor(), Map::kConstructorOffset); TagObject(map->dependent_code(), "(dependent code)"); SetInternalReference(map, entry, "dependent_code", map->dependent_code(), Map::kDependentCodeOffset); } void V8HeapExplorer::ExtractSharedFunctionInfoReferences( int entry, SharedFunctionInfo* shared) { HeapObject* obj = shared; SetInternalReference(obj, entry, "name", shared->name(), SharedFunctionInfo::kNameOffset); TagObject(shared->code(), "(code)"); SetInternalReference(obj, entry, "code", shared->code(), SharedFunctionInfo::kCodeOffset); TagObject(shared->scope_info(), "(function scope info)"); SetInternalReference(obj, entry, "scope_info", shared->scope_info(), SharedFunctionInfo::kScopeInfoOffset); SetInternalReference(obj, entry, "instance_class_name", shared->instance_class_name(), SharedFunctionInfo::kInstanceClassNameOffset); SetInternalReference(obj, entry, "script", shared->script(), SharedFunctionInfo::kScriptOffset); TagObject(shared->construct_stub(), "(code)"); SetInternalReference(obj, entry, "construct_stub", shared->construct_stub(), SharedFunctionInfo::kConstructStubOffset); SetInternalReference(obj, entry, "function_data", shared->function_data(), SharedFunctionInfo::kFunctionDataOffset); SetInternalReference(obj, entry, "debug_info", shared->debug_info(), SharedFunctionInfo::kDebugInfoOffset); SetInternalReference(obj, entry, "inferred_name", shared->inferred_name(), SharedFunctionInfo::kInferredNameOffset); SetWeakReference(obj, entry, 1, shared->initial_map(), SharedFunctionInfo::kInitialMapOffset); } void V8HeapExplorer::ExtractScriptReferences(int entry, Script* script) { HeapObject* obj = script; SetInternalReference(obj, entry, "source", script->source(), Script::kSourceOffset); SetInternalReference(obj, entry, "name", script->name(), Script::kNameOffset); SetInternalReference(obj, entry, "data", script->data(), Script::kDataOffset); SetInternalReference(obj, entry, "context_data", script->context_data(), Script::kContextOffset); TagObject(script->line_ends(), "(script line ends)"); SetInternalReference(obj, entry, "line_ends", script->line_ends(), Script::kLineEndsOffset); } void V8HeapExplorer::ExtractAccessorPairReferences( int entry, AccessorPair* accessors) { SetInternalReference(accessors, entry, "getter", accessors->getter(), AccessorPair::kGetterOffset); SetInternalReference(accessors, entry, "setter", accessors->setter(), AccessorPair::kSetterOffset); } void V8HeapExplorer::ExtractCodeCacheReferences( int entry, CodeCache* code_cache) { TagObject(code_cache->default_cache(), "(default code cache)"); SetInternalReference(code_cache, entry, "default_cache", code_cache->default_cache(), CodeCache::kDefaultCacheOffset); TagObject(code_cache->normal_type_cache(), "(code type cache)"); SetInternalReference(code_cache, entry, "type_cache", code_cache->normal_type_cache(), CodeCache::kNormalTypeCacheOffset); } void V8HeapExplorer::ExtractCodeReferences(int entry, Code* code) { TagObject(code->relocation_info(), "(code relocation info)"); SetInternalReference(code, entry, "relocation_info", code->relocation_info(), Code::kRelocationInfoOffset); SetInternalReference(code, entry, "handler_table", code->handler_table(), Code::kHandlerTableOffset); TagObject(code->deoptimization_data(), "(code deopt data)"); SetInternalReference(code, entry, "deoptimization_data", code->deoptimization_data(), Code::kDeoptimizationDataOffset); if (code->kind() == Code::FUNCTION) { SetInternalReference(code, entry, "type_feedback_info", code->type_feedback_info(), Code::kTypeFeedbackInfoOffset); } SetInternalReference(code, entry, "gc_metadata", code->gc_metadata(), Code::kGCMetadataOffset); } void V8HeapExplorer::ExtractCellReferences(int entry, Cell* cell) { SetInternalReference(cell, entry, "value", cell->value(), Cell::kValueOffset); } void V8HeapExplorer::ExtractPropertyCellReferences(int entry, PropertyCell* cell) { ExtractCellReferences(entry, cell); SetInternalReference(cell, entry, "type", cell->type(), PropertyCell::kTypeOffset); SetInternalReference(cell, entry, "dependent_code", cell->dependent_code(), PropertyCell::kDependentCodeOffset); } void V8HeapExplorer::ExtractAllocationSiteReferences(int entry, AllocationSite* site) { SetInternalReference(site, entry, "transition_info", site->transition_info(), AllocationSite::kTransitionInfoOffset); } void V8HeapExplorer::ExtractClosureReferences(JSObject* js_obj, int entry) { if (!js_obj->IsJSFunction()) return; JSFunction* func = JSFunction::cast(js_obj); if (func->shared()->bound()) { FixedArray* bindings = func->function_bindings(); SetNativeBindReference(js_obj, entry, "bound_this", bindings->get(JSFunction::kBoundThisIndex)); SetNativeBindReference(js_obj, entry, "bound_function", bindings->get(JSFunction::kBoundFunctionIndex)); for (int i = JSFunction::kBoundArgumentsStartIndex; i < bindings->length(); i++) { const char* reference_name = collection_->names()->GetFormatted( "bound_argument_%d", i - JSFunction::kBoundArgumentsStartIndex); SetNativeBindReference(js_obj, entry, reference_name, bindings->get(i)); } } } void V8HeapExplorer::ExtractPropertyReferences(JSObject* js_obj, int entry) { if (js_obj->HasFastProperties()) { DescriptorArray* descs = js_obj->map()->instance_descriptors(); int real_size = js_obj->map()->NumberOfOwnDescriptors(); for (int i = 0; i < real_size; i++) { switch (descs->GetType(i)) { case FIELD: { int index = descs->GetFieldIndex(i); Name* k = descs->GetKey(i); if (index < js_obj->map()->inobject_properties()) { Object* value = js_obj->InObjectPropertyAt(index); if (k != heap_->hidden_string()) { SetPropertyReference( js_obj, entry, k, value, NULL, js_obj->GetInObjectPropertyOffset(index)); } else { TagObject(value, "(hidden properties)"); SetInternalReference( js_obj, entry, "hidden_properties", value, js_obj->GetInObjectPropertyOffset(index)); } } else { Object* value = js_obj->RawFastPropertyAt(index); if (k != heap_->hidden_string()) { SetPropertyReference(js_obj, entry, k, value); } else { TagObject(value, "(hidden properties)"); SetInternalReference(js_obj, entry, "hidden_properties", value); } } break; } case CONSTANT: SetPropertyReference( js_obj, entry, descs->GetKey(i), descs->GetConstant(i)); break; case CALLBACKS: ExtractAccessorPairProperty( js_obj, entry, descs->GetKey(i), descs->GetValue(i)); break; case NORMAL: // only in slow mode case HANDLER: // only in lookup results, not in descriptors case INTERCEPTOR: // only in lookup results, not in descriptors break; case TRANSITION: case NONEXISTENT: UNREACHABLE(); break; } } } else { NameDictionary* dictionary = js_obj->property_dictionary(); int length = dictionary->Capacity(); for (int i = 0; i < length; ++i) { Object* k = dictionary->KeyAt(i); if (dictionary->IsKey(k)) { Object* target = dictionary->ValueAt(i); // We assume that global objects can only have slow properties. Object* value = target->IsPropertyCell() ? PropertyCell::cast(target)->value() : target; if (k == heap_->hidden_string()) { TagObject(value, "(hidden properties)"); SetInternalReference(js_obj, entry, "hidden_properties", value); continue; } if (ExtractAccessorPairProperty(js_obj, entry, k, value)) continue; SetPropertyReference(js_obj, entry, String::cast(k), value); } } } } bool V8HeapExplorer::ExtractAccessorPairProperty( JSObject* js_obj, int entry, Object* key, Object* callback_obj) { if (!callback_obj->IsAccessorPair()) return false; AccessorPair* accessors = AccessorPair::cast(callback_obj); Object* getter = accessors->getter(); if (!getter->IsOddball()) { SetPropertyReference(js_obj, entry, String::cast(key), getter, "get %s"); } Object* setter = accessors->setter(); if (!setter->IsOddball()) { SetPropertyReference(js_obj, entry, String::cast(key), setter, "set %s"); } return true; } void V8HeapExplorer::ExtractElementReferences(JSObject* js_obj, int entry) { if (js_obj->HasFastObjectElements()) { FixedArray* elements = FixedArray::cast(js_obj->elements()); int length = js_obj->IsJSArray() ? Smi::cast(JSArray::cast(js_obj)->length())->value() : elements->length(); for (int i = 0; i < length; ++i) { if (!elements->get(i)->IsTheHole()) { SetElementReference(js_obj, entry, i, elements->get(i)); } } } else if (js_obj->HasDictionaryElements()) { SeededNumberDictionary* dictionary = js_obj->element_dictionary(); int length = dictionary->Capacity(); for (int i = 0; i < length; ++i) { Object* k = dictionary->KeyAt(i); if (dictionary->IsKey(k)) { ASSERT(k->IsNumber()); uint32_t index = static_cast(k->Number()); SetElementReference(js_obj, entry, index, dictionary->ValueAt(i)); } } } } void V8HeapExplorer::ExtractInternalReferences(JSObject* js_obj, int entry) { int length = js_obj->GetInternalFieldCount(); for (int i = 0; i < length; ++i) { Object* o = js_obj->GetInternalField(i); SetInternalReference( js_obj, entry, i, o, js_obj->GetInternalFieldOffset(i)); } } String* V8HeapExplorer::GetConstructorName(JSObject* object) { Heap* heap = object->GetHeap(); if (object->IsJSFunction()) return heap->closure_string(); String* constructor_name = object->constructor_name(); if (constructor_name == heap->Object_string()) { // Look up an immediate "constructor" property, if it is a function, // return its name. This is for instances of binding objects, which // have prototype constructor type "Object". Object* constructor_prop = NULL; LookupResult result(heap->isolate()); object->LocalLookupRealNamedProperty(heap->constructor_string(), &result); if (!result.IsFound()) return object->constructor_name(); constructor_prop = result.GetLazyValue(); if (constructor_prop->IsJSFunction()) { Object* maybe_name = JSFunction::cast(constructor_prop)->shared()->name(); if (maybe_name->IsString()) { String* name = String::cast(maybe_name); if (name->length() > 0) return name; } } } return object->constructor_name(); } HeapEntry* V8HeapExplorer::GetEntry(Object* obj) { if (!obj->IsHeapObject()) return NULL; return filler_->FindOrAddEntry(obj, this); } class RootsReferencesExtractor : public ObjectVisitor { private: struct IndexTag { IndexTag(int index, VisitorSynchronization::SyncTag tag) : index(index), tag(tag) { } int index; VisitorSynchronization::SyncTag tag; }; public: RootsReferencesExtractor() : collecting_all_references_(false), previous_reference_count_(0) { } void VisitPointers(Object** start, Object** end) { if (collecting_all_references_) { for (Object** p = start; p < end; p++) all_references_.Add(*p); } else { for (Object** p = start; p < end; p++) strong_references_.Add(*p); } } void SetCollectingAllReferences() { collecting_all_references_ = true; } void FillReferences(V8HeapExplorer* explorer) { ASSERT(strong_references_.length() <= all_references_.length()); for (int i = 0; i < reference_tags_.length(); ++i) { explorer->SetGcRootsReference(reference_tags_[i].tag); } int strong_index = 0, all_index = 0, tags_index = 0; while (all_index < all_references_.length()) { if (strong_index < strong_references_.length() && strong_references_[strong_index] == all_references_[all_index]) { explorer->SetGcSubrootReference(reference_tags_[tags_index].tag, false, all_references_[all_index++]); ++strong_index; } else { explorer->SetGcSubrootReference(reference_tags_[tags_index].tag, true, all_references_[all_index++]); } if (reference_tags_[tags_index].index == all_index) ++tags_index; } } void Synchronize(VisitorSynchronization::SyncTag tag) { if (collecting_all_references_ && previous_reference_count_ != all_references_.length()) { previous_reference_count_ = all_references_.length(); reference_tags_.Add(IndexTag(previous_reference_count_, tag)); } } private: bool collecting_all_references_; List strong_references_; List all_references_; int previous_reference_count_; List reference_tags_; }; bool V8HeapExplorer::IterateAndExtractReferences( SnapshotFillerInterface* filler) { HeapIterator iterator(heap_, HeapIterator::kFilterUnreachable); filler_ = filler; bool interrupted = false; // Heap iteration with filtering must be finished in any case. for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next(), progress_->ProgressStep()) { if (!interrupted) { ExtractReferences(obj); if (!progress_->ProgressReport(false)) interrupted = true; } } if (interrupted) { filler_ = NULL; return false; } SetRootGcRootsReference(); RootsReferencesExtractor extractor; heap_->IterateRoots(&extractor, VISIT_ONLY_STRONG); extractor.SetCollectingAllReferences(); heap_->IterateRoots(&extractor, VISIT_ALL); extractor.FillReferences(this); filler_ = NULL; return progress_->ProgressReport(true); } bool V8HeapExplorer::IsEssentialObject(Object* object) { return object->IsHeapObject() && !object->IsOddball() && object != heap_->empty_byte_array() && object != heap_->empty_fixed_array() && object != heap_->empty_descriptor_array() && object != heap_->fixed_array_map() && object != heap_->cell_map() && object != heap_->global_property_cell_map() && object != heap_->shared_function_info_map() && object != heap_->free_space_map() && object != heap_->one_pointer_filler_map() && object != heap_->two_pointer_filler_map(); } void V8HeapExplorer::SetContextReference(HeapObject* parent_obj, int parent_entry, String* reference_name, Object* child_obj, int field_offset) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry != NULL) { filler_->SetNamedReference(HeapGraphEdge::kContextVariable, parent_entry, collection_->names()->GetName(reference_name), child_entry); IndexedReferencesExtractor::MarkVisitedField(parent_obj, field_offset); } } void V8HeapExplorer::SetNativeBindReference(HeapObject* parent_obj, int parent_entry, const char* reference_name, Object* child_obj) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry != NULL) { filler_->SetNamedReference(HeapGraphEdge::kShortcut, parent_entry, reference_name, child_entry); } } void V8HeapExplorer::SetElementReference(HeapObject* parent_obj, int parent_entry, int index, Object* child_obj) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry != NULL) { filler_->SetIndexedReference(HeapGraphEdge::kElement, parent_entry, index, child_entry); } } void V8HeapExplorer::SetInternalReference(HeapObject* parent_obj, int parent_entry, const char* reference_name, Object* child_obj, int field_offset) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry == NULL) return; if (IsEssentialObject(child_obj)) { filler_->SetNamedReference(HeapGraphEdge::kInternal, parent_entry, reference_name, child_entry); } IndexedReferencesExtractor::MarkVisitedField(parent_obj, field_offset); } void V8HeapExplorer::SetInternalReference(HeapObject* parent_obj, int parent_entry, int index, Object* child_obj, int field_offset) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry == NULL) return; if (IsEssentialObject(child_obj)) { filler_->SetNamedReference(HeapGraphEdge::kInternal, parent_entry, collection_->names()->GetName(index), child_entry); } IndexedReferencesExtractor::MarkVisitedField(parent_obj, field_offset); } void V8HeapExplorer::SetHiddenReference(HeapObject* parent_obj, int parent_entry, int index, Object* child_obj) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry != NULL && IsEssentialObject(child_obj)) { filler_->SetIndexedReference(HeapGraphEdge::kHidden, parent_entry, index, child_entry); } } void V8HeapExplorer::SetWeakReference(HeapObject* parent_obj, int parent_entry, int index, Object* child_obj, int field_offset) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry == NULL) return; if (IsEssentialObject(child_obj)) { filler_->SetIndexedReference(HeapGraphEdge::kWeak, parent_entry, index, child_entry); } IndexedReferencesExtractor::MarkVisitedField(parent_obj, field_offset); } void V8HeapExplorer::SetPropertyReference(HeapObject* parent_obj, int parent_entry, Name* reference_name, Object* child_obj, const char* name_format_string, int field_offset) { ASSERT(parent_entry == GetEntry(parent_obj)->index()); HeapEntry* child_entry = GetEntry(child_obj); if (child_entry != NULL) { HeapGraphEdge::Type type = reference_name->IsSymbol() || String::cast(reference_name)->length() > 0 ? HeapGraphEdge::kProperty : HeapGraphEdge::kInternal; const char* name = name_format_string != NULL && reference_name->IsString() ? collection_->names()->GetFormatted( name_format_string, *String::cast(reference_name)->ToCString( DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL)) : collection_->names()->GetName(reference_name); filler_->SetNamedReference(type, parent_entry, name, child_entry); IndexedReferencesExtractor::MarkVisitedField(parent_obj, field_offset); } } void V8HeapExplorer::SetRootGcRootsReference() { filler_->SetIndexedAutoIndexReference( HeapGraphEdge::kElement, snapshot_->root()->index(), snapshot_->gc_roots()); } void V8HeapExplorer::SetUserGlobalReference(Object* child_obj) { HeapEntry* child_entry = GetEntry(child_obj); ASSERT(child_entry != NULL); filler_->SetNamedAutoIndexReference( HeapGraphEdge::kShortcut, snapshot_->root()->index(), child_entry); } void V8HeapExplorer::SetGcRootsReference(VisitorSynchronization::SyncTag tag) { filler_->SetIndexedAutoIndexReference( HeapGraphEdge::kElement, snapshot_->gc_roots()->index(), snapshot_->gc_subroot(tag)); } void V8HeapExplorer::SetGcSubrootReference( VisitorSynchronization::SyncTag tag, bool is_weak, Object* child_obj) { HeapEntry* child_entry = GetEntry(child_obj); if (child_entry != NULL) { const char* name = GetStrongGcSubrootName(child_obj); if (name != NULL) { filler_->SetNamedReference( HeapGraphEdge::kInternal, snapshot_->gc_subroot(tag)->index(), name, child_entry); } else { filler_->SetIndexedAutoIndexReference( is_weak ? HeapGraphEdge::kWeak : HeapGraphEdge::kElement, snapshot_->gc_subroot(tag)->index(), child_entry); } // Add a shortcut to JS global object reference at snapshot root. if (child_obj->IsNativeContext()) { Context* context = Context::cast(child_obj); GlobalObject* global = context->global_object(); if (global->IsJSGlobalObject()) { bool is_debug_object = false; #ifdef ENABLE_DEBUGGER_SUPPORT is_debug_object = heap_->isolate()->debug()->IsDebugGlobal(global); #endif if (!is_debug_object && !user_roots_.Contains(global)) { user_roots_.Insert(global); SetUserGlobalReference(global); } } } } } const char* V8HeapExplorer::GetStrongGcSubrootName(Object* object) { if (strong_gc_subroot_names_.is_empty()) { #define NAME_ENTRY(name) strong_gc_subroot_names_.SetTag(heap_->name(), #name); #define ROOT_NAME(type, name, camel_name) NAME_ENTRY(name) STRONG_ROOT_LIST(ROOT_NAME) #undef ROOT_NAME #define STRUCT_MAP_NAME(NAME, Name, name) NAME_ENTRY(name##_map) STRUCT_LIST(STRUCT_MAP_NAME) #undef STRUCT_MAP_NAME #define STRING_NAME(name, str) NAME_ENTRY(name) INTERNALIZED_STRING_LIST(STRING_NAME) #undef STRING_NAME #undef NAME_ENTRY CHECK(!strong_gc_subroot_names_.is_empty()); } return strong_gc_subroot_names_.GetTag(object); } void V8HeapExplorer::TagObject(Object* obj, const char* tag) { if (IsEssentialObject(obj)) { HeapEntry* entry = GetEntry(obj); if (entry->name()[0] == '\0') { entry->set_name(tag); } } } class GlobalObjectsEnumerator : public ObjectVisitor { public: virtual void VisitPointers(Object** start, Object** end) { for (Object** p = start; p < end; p++) { if ((*p)->IsNativeContext()) { Context* context = Context::cast(*p); JSObject* proxy = context->global_proxy(); if (proxy->IsJSGlobalProxy()) { Object* global = proxy->map()->prototype(); if (global->IsJSGlobalObject()) { objects_.Add(Handle(JSGlobalObject::cast(global))); } } } } } int count() { return objects_.length(); } Handle& at(int i) { return objects_[i]; } private: List > objects_; }; // Modifies heap. Must not be run during heap traversal. void V8HeapExplorer::TagGlobalObjects() { Isolate* isolate = Isolate::Current(); HandleScope scope(isolate); GlobalObjectsEnumerator enumerator; isolate->global_handles()->IterateAllRoots(&enumerator); const char** urls = NewArray(enumerator.count()); for (int i = 0, l = enumerator.count(); i < l; ++i) { if (global_object_name_resolver_) { HandleScope scope(isolate); Handle global_obj = enumerator.at(i); urls[i] = global_object_name_resolver_->GetName( Utils::ToLocal(Handle::cast(global_obj))); } else { urls[i] = NULL; } } DisallowHeapAllocation no_allocation; for (int i = 0, l = enumerator.count(); i < l; ++i) { objects_tags_.SetTag(*enumerator.at(i), urls[i]); } DeleteArray(urls); } class GlobalHandlesExtractor : public ObjectVisitor { public: explicit GlobalHandlesExtractor(NativeObjectsExplorer* explorer) : explorer_(explorer) {} virtual ~GlobalHandlesExtractor() {} virtual void VisitPointers(Object** start, Object** end) { UNREACHABLE(); } virtual void VisitEmbedderReference(Object** p, uint16_t class_id) { explorer_->VisitSubtreeWrapper(p, class_id); } private: NativeObjectsExplorer* explorer_; }; class BasicHeapEntriesAllocator : public HeapEntriesAllocator { public: BasicHeapEntriesAllocator( HeapSnapshot* snapshot, HeapEntry::Type entries_type) : snapshot_(snapshot), collection_(snapshot_->collection()), entries_type_(entries_type) { } virtual HeapEntry* AllocateEntry(HeapThing ptr); private: HeapSnapshot* snapshot_; HeapSnapshotsCollection* collection_; HeapEntry::Type entries_type_; }; HeapEntry* BasicHeapEntriesAllocator::AllocateEntry(HeapThing ptr) { v8::RetainedObjectInfo* info = reinterpret_cast(ptr); intptr_t elements = info->GetElementCount(); intptr_t size = info->GetSizeInBytes(); const char* name = elements != -1 ? collection_->names()->GetFormatted( "%s / %" V8_PTR_PREFIX "d entries", info->GetLabel(), elements) : collection_->names()->GetCopy(info->GetLabel()); return snapshot_->AddEntry( entries_type_, name, HeapObjectsMap::GenerateId(info), size != -1 ? static_cast(size) : 0); } NativeObjectsExplorer::NativeObjectsExplorer( HeapSnapshot* snapshot, SnapshottingProgressReportingInterface* progress) : snapshot_(snapshot), collection_(snapshot_->collection()), progress_(progress), embedder_queried_(false), objects_by_info_(RetainedInfosMatch), native_groups_(StringsMatch), filler_(NULL) { synthetic_entries_allocator_ = new BasicHeapEntriesAllocator(snapshot, HeapEntry::kSynthetic); native_entries_allocator_ = new BasicHeapEntriesAllocator(snapshot, HeapEntry::kNative); } NativeObjectsExplorer::~NativeObjectsExplorer() { for (HashMap::Entry* p = objects_by_info_.Start(); p != NULL; p = objects_by_info_.Next(p)) { v8::RetainedObjectInfo* info = reinterpret_cast(p->key); info->Dispose(); List* objects = reinterpret_cast* >(p->value); delete objects; } for (HashMap::Entry* p = native_groups_.Start(); p != NULL; p = native_groups_.Next(p)) { v8::RetainedObjectInfo* info = reinterpret_cast(p->value); info->Dispose(); } delete synthetic_entries_allocator_; delete native_entries_allocator_; } int NativeObjectsExplorer::EstimateObjectsCount() { FillRetainedObjects(); return objects_by_info_.occupancy(); } void NativeObjectsExplorer::FillRetainedObjects() { if (embedder_queried_) return; Isolate* isolate = Isolate::Current(); const GCType major_gc_type = kGCTypeMarkSweepCompact; // Record objects that are joined into ObjectGroups. isolate->heap()->CallGCPrologueCallbacks( major_gc_type, kGCCallbackFlagConstructRetainedObjectInfos); List* groups = isolate->global_handles()->object_groups(); for (int i = 0; i < groups->length(); ++i) { ObjectGroup* group = groups->at(i); if (group->info == NULL) continue; List* list = GetListMaybeDisposeInfo(group->info); for (size_t j = 0; j < group->length; ++j) { HeapObject* obj = HeapObject::cast(*group->objects[j]); list->Add(obj); in_groups_.Insert(obj); } group->info = NULL; // Acquire info object ownership. } isolate->global_handles()->RemoveObjectGroups(); isolate->heap()->CallGCEpilogueCallbacks(major_gc_type); // Record objects that are not in ObjectGroups, but have class ID. GlobalHandlesExtractor extractor(this); isolate->global_handles()->IterateAllRootsWithClassIds(&extractor); embedder_queried_ = true; } void NativeObjectsExplorer::FillImplicitReferences() { Isolate* isolate = Isolate::Current(); List* groups = isolate->global_handles()->implicit_ref_groups(); for (int i = 0; i < groups->length(); ++i) { ImplicitRefGroup* group = groups->at(i); HeapObject* parent = *group->parent; int parent_entry = filler_->FindOrAddEntry(parent, native_entries_allocator_)->index(); ASSERT(parent_entry != HeapEntry::kNoEntry); Object*** children = group->children; for (size_t j = 0; j < group->length; ++j) { Object* child = *children[j]; HeapEntry* child_entry = filler_->FindOrAddEntry(child, native_entries_allocator_); filler_->SetNamedReference( HeapGraphEdge::kInternal, parent_entry, "native", child_entry); } } isolate->global_handles()->RemoveImplicitRefGroups(); } List* NativeObjectsExplorer::GetListMaybeDisposeInfo( v8::RetainedObjectInfo* info) { HashMap::Entry* entry = objects_by_info_.Lookup(info, InfoHash(info), true); if (entry->value != NULL) { info->Dispose(); } else { entry->value = new List(4); } return reinterpret_cast* >(entry->value); } bool NativeObjectsExplorer::IterateAndExtractReferences( SnapshotFillerInterface* filler) { filler_ = filler; FillRetainedObjects(); FillImplicitReferences(); if (EstimateObjectsCount() > 0) { for (HashMap::Entry* p = objects_by_info_.Start(); p != NULL; p = objects_by_info_.Next(p)) { v8::RetainedObjectInfo* info = reinterpret_cast(p->key); SetNativeRootReference(info); List* objects = reinterpret_cast* >(p->value); for (int i = 0; i < objects->length(); ++i) { SetWrapperNativeReferences(objects->at(i), info); } } SetRootNativeRootsReference(); } filler_ = NULL; return true; } class NativeGroupRetainedObjectInfo : public v8::RetainedObjectInfo { public: explicit NativeGroupRetainedObjectInfo(const char* label) : disposed_(false), hash_(reinterpret_cast(label)), label_(label) { } virtual ~NativeGroupRetainedObjectInfo() {} virtual void Dispose() { CHECK(!disposed_); disposed_ = true; delete this; } virtual bool IsEquivalent(RetainedObjectInfo* other) { return hash_ == other->GetHash() && !strcmp(label_, other->GetLabel()); } virtual intptr_t GetHash() { return hash_; } virtual const char* GetLabel() { return label_; } private: bool disposed_; intptr_t hash_; const char* label_; }; NativeGroupRetainedObjectInfo* NativeObjectsExplorer::FindOrAddGroupInfo( const char* label) { const char* label_copy = collection_->names()->GetCopy(label); uint32_t hash = StringHasher::HashSequentialString( label_copy, static_cast(strlen(label_copy)), HEAP->HashSeed()); HashMap::Entry* entry = native_groups_.Lookup(const_cast(label_copy), hash, true); if (entry->value == NULL) { entry->value = new NativeGroupRetainedObjectInfo(label); } return static_cast(entry->value); } void NativeObjectsExplorer::SetNativeRootReference( v8::RetainedObjectInfo* info) { HeapEntry* child_entry = filler_->FindOrAddEntry(info, native_entries_allocator_); ASSERT(child_entry != NULL); NativeGroupRetainedObjectInfo* group_info = FindOrAddGroupInfo(info->GetGroupLabel()); HeapEntry* group_entry = filler_->FindOrAddEntry(group_info, synthetic_entries_allocator_); filler_->SetNamedAutoIndexReference( HeapGraphEdge::kInternal, group_entry->index(), child_entry); } void NativeObjectsExplorer::SetWrapperNativeReferences( HeapObject* wrapper, v8::RetainedObjectInfo* info) { HeapEntry* wrapper_entry = filler_->FindEntry(wrapper); ASSERT(wrapper_entry != NULL); HeapEntry* info_entry = filler_->FindOrAddEntry(info, native_entries_allocator_); ASSERT(info_entry != NULL); filler_->SetNamedReference(HeapGraphEdge::kInternal, wrapper_entry->index(), "native", info_entry); filler_->SetIndexedAutoIndexReference(HeapGraphEdge::kElement, info_entry->index(), wrapper_entry); } void NativeObjectsExplorer::SetRootNativeRootsReference() { for (HashMap::Entry* entry = native_groups_.Start(); entry; entry = native_groups_.Next(entry)) { NativeGroupRetainedObjectInfo* group_info = static_cast(entry->value); HeapEntry* group_entry = filler_->FindOrAddEntry(group_info, native_entries_allocator_); ASSERT(group_entry != NULL); filler_->SetIndexedAutoIndexReference( HeapGraphEdge::kElement, snapshot_->root()->index(), group_entry); } } void NativeObjectsExplorer::VisitSubtreeWrapper(Object** p, uint16_t class_id) { if (in_groups_.Contains(*p)) return; Isolate* isolate = Isolate::Current(); v8::RetainedObjectInfo* info = isolate->heap_profiler()->ExecuteWrapperClassCallback(class_id, p); if (info == NULL) return; GetListMaybeDisposeInfo(info)->Add(HeapObject::cast(*p)); } class SnapshotFiller : public SnapshotFillerInterface { public: explicit SnapshotFiller(HeapSnapshot* snapshot, HeapEntriesMap* entries) : snapshot_(snapshot), collection_(snapshot->collection()), entries_(entries) { } HeapEntry* AddEntry(HeapThing ptr, HeapEntriesAllocator* allocator) { HeapEntry* entry = allocator->AllocateEntry(ptr); entries_->Pair(ptr, entry->index()); return entry; } HeapEntry* FindEntry(HeapThing ptr) { int index = entries_->Map(ptr); return index != HeapEntry::kNoEntry ? &snapshot_->entries()[index] : NULL; } HeapEntry* FindOrAddEntry(HeapThing ptr, HeapEntriesAllocator* allocator) { HeapEntry* entry = FindEntry(ptr); return entry != NULL ? entry : AddEntry(ptr, allocator); } void SetIndexedReference(HeapGraphEdge::Type type, int parent, int index, HeapEntry* child_entry) { HeapEntry* parent_entry = &snapshot_->entries()[parent]; parent_entry->SetIndexedReference(type, index, child_entry); } void SetIndexedAutoIndexReference(HeapGraphEdge::Type type, int parent, HeapEntry* child_entry) { HeapEntry* parent_entry = &snapshot_->entries()[parent]; int index = parent_entry->children_count() + 1; parent_entry->SetIndexedReference(type, index, child_entry); } void SetNamedReference(HeapGraphEdge::Type type, int parent, const char* reference_name, HeapEntry* child_entry) { HeapEntry* parent_entry = &snapshot_->entries()[parent]; parent_entry->SetNamedReference(type, reference_name, child_entry); } void SetNamedAutoIndexReference(HeapGraphEdge::Type type, int parent, HeapEntry* child_entry) { HeapEntry* parent_entry = &snapshot_->entries()[parent]; int index = parent_entry->children_count() + 1; parent_entry->SetNamedReference( type, collection_->names()->GetName(index), child_entry); } private: HeapSnapshot* snapshot_; HeapSnapshotsCollection* collection_; HeapEntriesMap* entries_; }; HeapSnapshotGenerator::HeapSnapshotGenerator( HeapSnapshot* snapshot, v8::ActivityControl* control, v8::HeapProfiler::ObjectNameResolver* resolver, Heap* heap) : snapshot_(snapshot), control_(control), v8_heap_explorer_(snapshot_, this, resolver), dom_explorer_(snapshot_, this), heap_(heap) { } bool HeapSnapshotGenerator::GenerateSnapshot() { v8_heap_explorer_.TagGlobalObjects(); // TODO(1562) Profiler assumes that any object that is in the heap after // full GC is reachable from the root when computing dominators. // This is not true for weakly reachable objects. // As a temporary solution we call GC twice. Isolate::Current()->heap()->CollectAllGarbage( Heap::kMakeHeapIterableMask, "HeapSnapshotGenerator::GenerateSnapshot"); Isolate::Current()->heap()->CollectAllGarbage( Heap::kMakeHeapIterableMask, "HeapSnapshotGenerator::GenerateSnapshot"); #ifdef VERIFY_HEAP Heap* debug_heap = Isolate::Current()->heap(); CHECK(!debug_heap->old_data_space()->was_swept_conservatively()); CHECK(!debug_heap->old_pointer_space()->was_swept_conservatively()); CHECK(!debug_heap->code_space()->was_swept_conservatively()); CHECK(!debug_heap->cell_space()->was_swept_conservatively()); CHECK(!debug_heap->property_cell_space()-> was_swept_conservatively()); CHECK(!debug_heap->map_space()->was_swept_conservatively()); #endif // The following code uses heap iterators, so we want the heap to be // stable. It should follow TagGlobalObjects as that can allocate. DisallowHeapAllocation no_alloc; #ifdef VERIFY_HEAP debug_heap->Verify(); #endif SetProgressTotal(1); // 1 pass. #ifdef VERIFY_HEAP debug_heap->Verify(); #endif if (!FillReferences()) return false; snapshot_->FillChildren(); snapshot_->RememberLastJSObjectId(); progress_counter_ = progress_total_; if (!ProgressReport(true)) return false; return true; } void HeapSnapshotGenerator::ProgressStep() { ++progress_counter_; } bool HeapSnapshotGenerator::ProgressReport(bool force) { const int kProgressReportGranularity = 10000; if (control_ != NULL && (force || progress_counter_ % kProgressReportGranularity == 0)) { return control_->ReportProgressValue(progress_counter_, progress_total_) == v8::ActivityControl::kContinue; } return true; } void HeapSnapshotGenerator::SetProgressTotal(int iterations_count) { if (control_ == NULL) return; HeapIterator iterator(heap_, HeapIterator::kFilterUnreachable); progress_total_ = iterations_count * ( v8_heap_explorer_.EstimateObjectsCount(&iterator) + dom_explorer_.EstimateObjectsCount()); progress_counter_ = 0; } bool HeapSnapshotGenerator::FillReferences() { SnapshotFiller filler(snapshot_, &entries_); v8_heap_explorer_.AddRootEntries(&filler); return v8_heap_explorer_.IterateAndExtractReferences(&filler) && dom_explorer_.IterateAndExtractReferences(&filler); } template struct MaxDecimalDigitsIn; template<> struct MaxDecimalDigitsIn<4> { static const int kSigned = 11; static const int kUnsigned = 10; }; template<> struct MaxDecimalDigitsIn<8> { static const int kSigned = 20; static const int kUnsigned = 20; }; class OutputStreamWriter { public: explicit OutputStreamWriter(v8::OutputStream* stream) : stream_(stream), chunk_size_(stream->GetChunkSize()), chunk_(chunk_size_), chunk_pos_(0), aborted_(false) { ASSERT(chunk_size_ > 0); } bool aborted() { return aborted_; } void AddCharacter(char c) { ASSERT(c != '\0'); ASSERT(chunk_pos_ < chunk_size_); chunk_[chunk_pos_++] = c; MaybeWriteChunk(); } void AddString(const char* s) { AddSubstring(s, StrLength(s)); } void AddSubstring(const char* s, int n) { if (n <= 0) return; ASSERT(static_cast(n) <= strlen(s)); const char* s_end = s + n; while (s < s_end) { int s_chunk_size = Min( chunk_size_ - chunk_pos_, static_cast(s_end - s)); ASSERT(s_chunk_size > 0); OS::MemCopy(chunk_.start() + chunk_pos_, s, s_chunk_size); s += s_chunk_size; chunk_pos_ += s_chunk_size; MaybeWriteChunk(); } } void AddNumber(unsigned n) { AddNumberImpl(n, "%u"); } void Finalize() { if (aborted_) return; ASSERT(chunk_pos_ < chunk_size_); if (chunk_pos_ != 0) { WriteChunk(); } stream_->EndOfStream(); } private: template void AddNumberImpl(T n, const char* format) { // Buffer for the longest value plus trailing \0 static const int kMaxNumberSize = MaxDecimalDigitsIn::kUnsigned + 1; if (chunk_size_ - chunk_pos_ >= kMaxNumberSize) { int result = OS::SNPrintF( chunk_.SubVector(chunk_pos_, chunk_size_), format, n); ASSERT(result != -1); chunk_pos_ += result; MaybeWriteChunk(); } else { EmbeddedVector buffer; int result = OS::SNPrintF(buffer, format, n); USE(result); ASSERT(result != -1); AddString(buffer.start()); } } void MaybeWriteChunk() { ASSERT(chunk_pos_ <= chunk_size_); if (chunk_pos_ == chunk_size_) { WriteChunk(); } } void WriteChunk() { if (aborted_) return; if (stream_->WriteAsciiChunk(chunk_.start(), chunk_pos_) == v8::OutputStream::kAbort) aborted_ = true; chunk_pos_ = 0; } v8::OutputStream* stream_; int chunk_size_; ScopedVector chunk_; int chunk_pos_; bool aborted_; }; // type, name|index, to_node. const int HeapSnapshotJSONSerializer::kEdgeFieldsCount = 3; // type, name, id, self_size, children_index. const int HeapSnapshotJSONSerializer::kNodeFieldsCount = 5; void HeapSnapshotJSONSerializer::Serialize(v8::OutputStream* stream) { ASSERT(writer_ == NULL); writer_ = new OutputStreamWriter(stream); SerializeImpl(); delete writer_; writer_ = NULL; } void HeapSnapshotJSONSerializer::SerializeImpl() { ASSERT(0 == snapshot_->root()->index()); writer_->AddCharacter('{'); writer_->AddString("\"snapshot\":{"); SerializeSnapshot(); if (writer_->aborted()) return; writer_->AddString("},\n"); writer_->AddString("\"nodes\":["); SerializeNodes(); if (writer_->aborted()) return; writer_->AddString("],\n"); writer_->AddString("\"edges\":["); SerializeEdges(); if (writer_->aborted()) return; writer_->AddString("],\n"); writer_->AddString("\"strings\":["); SerializeStrings(); if (writer_->aborted()) return; writer_->AddCharacter(']'); writer_->AddCharacter('}'); writer_->Finalize(); } int HeapSnapshotJSONSerializer::GetStringId(const char* s) { HashMap::Entry* cache_entry = strings_.Lookup( const_cast(s), ObjectHash(s), true); if (cache_entry->value == NULL) { cache_entry->value = reinterpret_cast(next_string_id_++); } return static_cast(reinterpret_cast(cache_entry->value)); } static int utoa(unsigned value, const Vector& buffer, int buffer_pos) { int number_of_digits = 0; unsigned t = value; do { ++number_of_digits; } while (t /= 10); buffer_pos += number_of_digits; int result = buffer_pos; do { int last_digit = value % 10; buffer[--buffer_pos] = '0' + last_digit; value /= 10; } while (value); return result; } void HeapSnapshotJSONSerializer::SerializeEdge(HeapGraphEdge* edge, bool first_edge) { // The buffer needs space for 3 unsigned ints, 3 commas, \n and \0 static const int kBufferSize = MaxDecimalDigitsIn::kUnsigned * 3 + 3 + 2; // NOLINT EmbeddedVector buffer; int edge_name_or_index = edge->type() == HeapGraphEdge::kElement || edge->type() == HeapGraphEdge::kHidden || edge->type() == HeapGraphEdge::kWeak ? edge->index() : GetStringId(edge->name()); int buffer_pos = 0; if (!first_edge) { buffer[buffer_pos++] = ','; } buffer_pos = utoa(edge->type(), buffer, buffer_pos); buffer[buffer_pos++] = ','; buffer_pos = utoa(edge_name_or_index, buffer, buffer_pos); buffer[buffer_pos++] = ','; buffer_pos = utoa(entry_index(edge->to()), buffer, buffer_pos); buffer[buffer_pos++] = '\n'; buffer[buffer_pos++] = '\0'; writer_->AddString(buffer.start()); } void HeapSnapshotJSONSerializer::SerializeEdges() { List& edges = snapshot_->children(); for (int i = 0; i < edges.length(); ++i) { ASSERT(i == 0 || edges[i - 1]->from()->index() <= edges[i]->from()->index()); SerializeEdge(edges[i], i == 0); if (writer_->aborted()) return; } } void HeapSnapshotJSONSerializer::SerializeNode(HeapEntry* entry) { // The buffer needs space for 5 unsigned ints, 5 commas, \n and \0 static const int kBufferSize = 5 * MaxDecimalDigitsIn::kUnsigned // NOLINT + 5 + 1 + 1; EmbeddedVector buffer; int buffer_pos = 0; if (entry_index(entry) != 0) { buffer[buffer_pos++] = ','; } buffer_pos = utoa(entry->type(), buffer, buffer_pos); buffer[buffer_pos++] = ','; buffer_pos = utoa(GetStringId(entry->name()), buffer, buffer_pos); buffer[buffer_pos++] = ','; buffer_pos = utoa(entry->id(), buffer, buffer_pos); buffer[buffer_pos++] = ','; buffer_pos = utoa(entry->self_size(), buffer, buffer_pos); buffer[buffer_pos++] = ','; buffer_pos = utoa(entry->children_count(), buffer, buffer_pos); buffer[buffer_pos++] = '\n'; buffer[buffer_pos++] = '\0'; writer_->AddString(buffer.start()); } void HeapSnapshotJSONSerializer::SerializeNodes() { List& entries = snapshot_->entries(); for (int i = 0; i < entries.length(); ++i) { SerializeNode(&entries[i]); if (writer_->aborted()) return; } } void HeapSnapshotJSONSerializer::SerializeSnapshot() { writer_->AddString("\"title\":\""); writer_->AddString(snapshot_->title()); writer_->AddString("\""); writer_->AddString(",\"uid\":"); writer_->AddNumber(snapshot_->uid()); writer_->AddString(",\"meta\":"); // The object describing node serialization layout. // We use a set of macros to improve readability. #define JSON_A(s) "[" s "]" #define JSON_O(s) "{" s "}" #define JSON_S(s) "\"" s "\"" writer_->AddString(JSON_O( JSON_S("node_fields") ":" JSON_A( JSON_S("type") "," JSON_S("name") "," JSON_S("id") "," JSON_S("self_size") "," JSON_S("edge_count")) "," JSON_S("node_types") ":" JSON_A( JSON_A( JSON_S("hidden") "," JSON_S("array") "," JSON_S("string") "," JSON_S("object") "," JSON_S("code") "," JSON_S("closure") "," JSON_S("regexp") "," JSON_S("number") "," JSON_S("native") "," JSON_S("synthetic")) "," JSON_S("string") "," JSON_S("number") "," JSON_S("number") "," JSON_S("number") "," JSON_S("number") "," JSON_S("number")) "," JSON_S("edge_fields") ":" JSON_A( JSON_S("type") "," JSON_S("name_or_index") "," JSON_S("to_node")) "," JSON_S("edge_types") ":" JSON_A( JSON_A( JSON_S("context") "," JSON_S("element") "," JSON_S("property") "," JSON_S("internal") "," JSON_S("hidden") "," JSON_S("shortcut") "," JSON_S("weak")) "," JSON_S("string_or_number") "," JSON_S("node")))); #undef JSON_S #undef JSON_O #undef JSON_A writer_->AddString(",\"node_count\":"); writer_->AddNumber(snapshot_->entries().length()); writer_->AddString(",\"edge_count\":"); writer_->AddNumber(snapshot_->edges().length()); } static void WriteUChar(OutputStreamWriter* w, unibrow::uchar u) { static const char hex_chars[] = "0123456789ABCDEF"; w->AddString("\\u"); w->AddCharacter(hex_chars[(u >> 12) & 0xf]); w->AddCharacter(hex_chars[(u >> 8) & 0xf]); w->AddCharacter(hex_chars[(u >> 4) & 0xf]); w->AddCharacter(hex_chars[u & 0xf]); } void HeapSnapshotJSONSerializer::SerializeString(const unsigned char* s) { writer_->AddCharacter('\n'); writer_->AddCharacter('\"'); for ( ; *s != '\0'; ++s) { switch (*s) { case '\b': writer_->AddString("\\b"); continue; case '\f': writer_->AddString("\\f"); continue; case '\n': writer_->AddString("\\n"); continue; case '\r': writer_->AddString("\\r"); continue; case '\t': writer_->AddString("\\t"); continue; case '\"': case '\\': writer_->AddCharacter('\\'); writer_->AddCharacter(*s); continue; default: if (*s > 31 && *s < 128) { writer_->AddCharacter(*s); } else if (*s <= 31) { // Special character with no dedicated literal. WriteUChar(writer_, *s); } else { // Convert UTF-8 into \u UTF-16 literal. unsigned length = 1, cursor = 0; for ( ; length <= 4 && *(s + length) != '\0'; ++length) { } unibrow::uchar c = unibrow::Utf8::CalculateValue(s, length, &cursor); if (c != unibrow::Utf8::kBadChar) { WriteUChar(writer_, c); ASSERT(cursor != 0); s += cursor - 1; } else { writer_->AddCharacter('?'); } } } } writer_->AddCharacter('\"'); } void HeapSnapshotJSONSerializer::SerializeStrings() { List sorted_strings; SortHashMap(&strings_, &sorted_strings); writer_->AddString("\"\""); for (int i = 0; i < sorted_strings.length(); ++i) { writer_->AddCharacter(','); SerializeString( reinterpret_cast(sorted_strings[i]->key)); if (writer_->aborted()) return; } } template inline static int SortUsingEntryValue(const T* x, const T* y) { uintptr_t x_uint = reinterpret_cast((*x)->value); uintptr_t y_uint = reinterpret_cast((*y)->value); if (x_uint > y_uint) { return 1; } else if (x_uint == y_uint) { return 0; } else { return -1; } } void HeapSnapshotJSONSerializer::SortHashMap( HashMap* map, List* sorted_entries) { for (HashMap::Entry* p = map->Start(); p != NULL; p = map->Next(p)) sorted_entries->Add(p); sorted_entries->Sort(SortUsingEntryValue); } } } // namespace v8::internal