// Copyright 2011 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. #ifdef LIVE_OBJECT_LIST #include <ctype.h> #include <stdlib.h> #include "v8.h" #include "checks.h" #include "global-handles.h" #include "heap.h" #include "inspector.h" #include "isolate.h" #include "list-inl.h" #include "liveobjectlist-inl.h" #include "string-stream.h" #include "v8utils.h" #include "v8conversions.h" namespace v8 { namespace internal { typedef int (*RawComparer)(const void*, const void*); #ifdef CHECK_ALL_OBJECT_TYPES #define DEBUG_LIVE_OBJECT_TYPES(v) \ v(Smi, "unexpected: Smi") \ \ v(CodeCache, "unexpected: CodeCache") \ v(BreakPointInfo, "unexpected: BreakPointInfo") \ v(DebugInfo, "unexpected: DebugInfo") \ v(TypeSwitchInfo, "unexpected: TypeSwitchInfo") \ v(SignatureInfo, "unexpected: SignatureInfo") \ v(Script, "unexpected: Script") \ v(ObjectTemplateInfo, "unexpected: ObjectTemplateInfo") \ v(FunctionTemplateInfo, "unexpected: FunctionTemplateInfo") \ v(CallHandlerInfo, "unexpected: CallHandlerInfo") \ v(InterceptorInfo, "unexpected: InterceptorInfo") \ v(AccessCheckInfo, "unexpected: AccessCheckInfo") \ v(AccessorInfo, "unexpected: AccessorInfo") \ v(ExternalTwoByteString, "unexpected: ExternalTwoByteString") \ v(ExternalAsciiString, "unexpected: ExternalAsciiString") \ v(ExternalString, "unexpected: ExternalString") \ v(SeqTwoByteString, "unexpected: SeqTwoByteString") \ v(SeqAsciiString, "unexpected: SeqAsciiString") \ v(SeqString, "unexpected: SeqString") \ v(JSFunctionResultCache, "unexpected: JSFunctionResultCache") \ v(GlobalContext, "unexpected: GlobalContext") \ v(MapCache, "unexpected: MapCache") \ v(CodeCacheHashTable, "unexpected: CodeCacheHashTable") \ v(CompilationCacheTable, "unexpected: CompilationCacheTable") \ v(SymbolTable, "unexpected: SymbolTable") \ v(Dictionary, "unexpected: Dictionary") \ v(HashTable, "unexpected: HashTable") \ v(DescriptorArray, "unexpected: DescriptorArray") \ v(ExternalFloatArray, "unexpected: ExternalFloatArray") \ v(ExternalUnsignedIntArray, "unexpected: ExternalUnsignedIntArray") \ v(ExternalIntArray, "unexpected: ExternalIntArray") \ v(ExternalUnsignedShortArray, "unexpected: ExternalUnsignedShortArray") \ v(ExternalShortArray, "unexpected: ExternalShortArray") \ v(ExternalUnsignedByteArray, "unexpected: ExternalUnsignedByteArray") \ v(ExternalByteArray, "unexpected: ExternalByteArray") \ v(JSValue, "unexpected: JSValue") #else #define DEBUG_LIVE_OBJECT_TYPES(v) #endif #define FOR_EACH_LIVE_OBJECT_TYPE(v) \ DEBUG_LIVE_OBJECT_TYPES(v) \ \ v(JSArray, "JSArray") \ v(JSRegExp, "JSRegExp") \ v(JSFunction, "JSFunction") \ v(JSGlobalObject, "JSGlobal") \ v(JSBuiltinsObject, "JSBuiltins") \ v(GlobalObject, "Global") \ v(JSGlobalProxy, "JSGlobalProxy") \ v(JSObject, "JSObject") \ \ v(Context, "meta: Context") \ v(ByteArray, "meta: ByteArray") \ v(ExternalPixelArray, "meta: PixelArray") \ v(ExternalArray, "meta: ExternalArray") \ v(FixedArray, "meta: FixedArray") \ v(String, "String") \ v(HeapNumber, "HeapNumber") \ \ v(Code, "meta: Code") \ v(Map, "meta: Map") \ v(Oddball, "Oddball") \ v(Foreign, "meta: Foreign") \ v(SharedFunctionInfo, "meta: SharedFunctionInfo") \ v(Struct, "meta: Struct") \ \ v(HeapObject, "HeapObject") enum /* LiveObjectType */ { #define DECLARE_OBJECT_TYPE_ENUM(type, name) kType##type, FOR_EACH_LIVE_OBJECT_TYPE(DECLARE_OBJECT_TYPE_ENUM) kInvalidLiveObjType, kNumberOfTypes #undef DECLARE_OBJECT_TYPE_ENUM }; LiveObjectType GetObjectType(HeapObject* heap_obj) { // TODO(mlam): investigate usint Map::instance_type() instead. #define CHECK_FOR_OBJECT_TYPE(type, name) \ if (heap_obj->Is##type()) return kType##type; FOR_EACH_LIVE_OBJECT_TYPE(CHECK_FOR_OBJECT_TYPE) #undef CHECK_FOR_OBJECT_TYPE UNREACHABLE(); return kInvalidLiveObjType; } inline const char* GetObjectTypeDesc(LiveObjectType type) { static const char* const name[kNumberOfTypes] = { #define DEFINE_OBJECT_TYPE_NAME(type, name) name, FOR_EACH_LIVE_OBJECT_TYPE(DEFINE_OBJECT_TYPE_NAME) "invalid" #undef DEFINE_OBJECT_TYPE_NAME }; ASSERT(type < kNumberOfTypes); return name[type]; } const char* GetObjectTypeDesc(HeapObject* heap_obj) { LiveObjectType type = GetObjectType(heap_obj); return GetObjectTypeDesc(type); } bool IsOfType(LiveObjectType type, HeapObject* obj) { // Note: there are types that are more general (e.g. JSObject) that would // have passed the Is##type_() test for more specialized types (e.g. // JSFunction). If we find a more specialized match but we're looking for // the general type, then we should reject the ones that matches the // specialized type. #define CHECK_OBJECT_TYPE(type_, name) \ if (obj->Is##type_()) return (type == kType##type_); FOR_EACH_LIVE_OBJECT_TYPE(CHECK_OBJECT_TYPE) #undef CHECK_OBJECT_TYPE return false; } const AllocationSpace kInvalidSpace = static_cast<AllocationSpace>(-1); static AllocationSpace FindSpaceFor(String* space_str) { SmartArrayPointer<char> s = space_str->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL); const char* key_str = *s; switch (key_str[0]) { case 'c': if (strcmp(key_str, "cell") == 0) return CELL_SPACE; if (strcmp(key_str, "code") == 0) return CODE_SPACE; break; case 'l': if (strcmp(key_str, "lo") == 0) return LO_SPACE; break; case 'm': if (strcmp(key_str, "map") == 0) return MAP_SPACE; break; case 'n': if (strcmp(key_str, "new") == 0) return NEW_SPACE; break; case 'o': if (strcmp(key_str, "old-pointer") == 0) return OLD_POINTER_SPACE; if (strcmp(key_str, "old-data") == 0) return OLD_DATA_SPACE; break; } return kInvalidSpace; } static bool InSpace(AllocationSpace space, HeapObject* heap_obj) { Heap* heap = ISOLATE->heap(); if (space != LO_SPACE) { return heap->InSpace(heap_obj, space); } // This is an optimization to speed up the check for an object in the LO // space by exclusion because we know that all object pointers passed in // here are guaranteed to be in the heap. Hence, it is safe to infer // using an exclusion test. // Note: calling Heap::InSpace(heap_obj, LO_SPACE) is too slow for our // filters. int first_space = static_cast<int>(FIRST_SPACE); int last_space = static_cast<int>(LO_SPACE); for (int sp = first_space; sp < last_space; sp++) { if (heap->InSpace(heap_obj, static_cast<AllocationSpace>(sp))) { return false; } } SLOW_ASSERT(heap->InSpace(heap_obj, LO_SPACE)); return true; } static LiveObjectType FindTypeFor(String* type_str) { SmartArrayPointer<char> s = type_str->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL); #define CHECK_OBJECT_TYPE(type_, name) { \ const char* type_desc = GetObjectTypeDesc(kType##type_); \ const char* key_str = *s; \ if (strstr(type_desc, key_str) != NULL) return kType##type_; \ } FOR_EACH_LIVE_OBJECT_TYPE(CHECK_OBJECT_TYPE) #undef CHECK_OBJECT_TYPE return kInvalidLiveObjType; } class LolFilter { public: explicit LolFilter(Handle<JSObject> filter_obj); inline bool is_active() const { return is_active_; } inline bool Matches(HeapObject* obj) { return !is_active() || MatchesSlow(obj); } private: void InitTypeFilter(Handle<JSObject> filter_obj); void InitSpaceFilter(Handle<JSObject> filter_obj); void InitPropertyFilter(Handle<JSObject> filter_obj); bool MatchesSlow(HeapObject* obj); bool is_active_; LiveObjectType type_; AllocationSpace space_; Handle<String> prop_; }; LolFilter::LolFilter(Handle<JSObject> filter_obj) : is_active_(false), type_(kInvalidLiveObjType), space_(kInvalidSpace), prop_() { if (filter_obj.is_null()) return; InitTypeFilter(filter_obj); InitSpaceFilter(filter_obj); InitPropertyFilter(filter_obj); } void LolFilter::InitTypeFilter(Handle<JSObject> filter_obj) { Handle<String> type_sym = FACTORY->LookupAsciiSymbol("type"); MaybeObject* maybe_result = filter_obj->GetProperty(*type_sym); Object* type_obj; if (maybe_result->ToObject(&type_obj)) { if (type_obj->IsString()) { String* type_str = String::cast(type_obj); type_ = FindTypeFor(type_str); if (type_ != kInvalidLiveObjType) { is_active_ = true; } } } } void LolFilter::InitSpaceFilter(Handle<JSObject> filter_obj) { Handle<String> space_sym = FACTORY->LookupAsciiSymbol("space"); MaybeObject* maybe_result = filter_obj->GetProperty(*space_sym); Object* space_obj; if (maybe_result->ToObject(&space_obj)) { if (space_obj->IsString()) { String* space_str = String::cast(space_obj); space_ = FindSpaceFor(space_str); if (space_ != kInvalidSpace) { is_active_ = true; } } } } void LolFilter::InitPropertyFilter(Handle<JSObject> filter_obj) { Handle<String> prop_sym = FACTORY->LookupAsciiSymbol("prop"); MaybeObject* maybe_result = filter_obj->GetProperty(*prop_sym); Object* prop_obj; if (maybe_result->ToObject(&prop_obj)) { if (prop_obj->IsString()) { prop_ = Handle<String>(String::cast(prop_obj)); is_active_ = true; } } } bool LolFilter::MatchesSlow(HeapObject* obj) { if ((type_ != kInvalidLiveObjType) && !IsOfType(type_, obj)) { return false; // Fail because obj is not of the type of interest. } if ((space_ != kInvalidSpace) && !InSpace(space_, obj)) { return false; // Fail because obj is not in the space of interest. } if (!prop_.is_null() && obj->IsJSObject()) { LookupResult result; obj->Lookup(*prop_, &result); if (!result.IsProperty()) { return false; // Fail because obj does not have the property of interest. } } return true; } class LolIterator { public: LolIterator(LiveObjectList* older, LiveObjectList* newer) : older_(older), newer_(newer), curr_(0), elements_(0), count_(0), index_(0) { } inline void Init() { SetCurrent(newer_); // If the elements_ list is empty, then move on to the next list as long // as we're not at the last list (indicated by done()). while ((elements_ == NULL) && !Done()) { SetCurrent(curr_->prev_); } } inline bool Done() const { return (curr_ == older_); } // Object level iteration. inline void Next() { index_++; if (index_ >= count_) { // Iterate backwards until we get to the oldest list. while (!Done()) { SetCurrent(curr_->prev_); // If we have elements to process, we're good to go. if (elements_ != NULL) break; // Else, we should advance to the next older list. } } } inline int Id() const { return elements_[index_].id_; } inline HeapObject* Obj() const { return elements_[index_].obj_; } inline int LolObjCount() const { if (curr_ != NULL) return curr_->obj_count_; return 0; } protected: inline void SetCurrent(LiveObjectList* new_curr) { curr_ = new_curr; if (curr_ != NULL) { elements_ = curr_->elements_; count_ = curr_->obj_count_; index_ = 0; } } LiveObjectList* older_; LiveObjectList* newer_; LiveObjectList* curr_; LiveObjectList::Element* elements_; int count_; int index_; }; class LolForwardIterator : public LolIterator { public: LolForwardIterator(LiveObjectList* first, LiveObjectList* last) : LolIterator(first, last) { } inline void Init() { SetCurrent(older_); // If the elements_ list is empty, then move on to the next list as long // as we're not at the last list (indicated by Done()). while ((elements_ == NULL) && !Done()) { SetCurrent(curr_->next_); } } inline bool Done() const { return (curr_ == newer_); } // Object level iteration. inline void Next() { index_++; if (index_ >= count_) { // Done with current list. Move on to the next. while (!Done()) { // If not at the last list already, ... SetCurrent(curr_->next_); // If we have elements to process, we're good to go. if (elements_ != NULL) break; // Else, we should advance to the next list. } } } }; // Minimizes the white space in a string. Tabs and newlines are replaced // with a space where appropriate. static int CompactString(char* str) { char* src = str; char* dst = str; char prev_ch = 0; while (*dst != '\0') { char ch = *src++; // We will treat non-ASCII chars as '?'. if ((ch & 0x80) != 0) { ch = '?'; } // Compact contiguous whitespace chars into a single ' '. if (isspace(ch)) { if (prev_ch != ' ') *dst++ = ' '; prev_ch = ' '; continue; } *dst++ = ch; prev_ch = ch; } return (dst - str); } // Generates a custom description based on the specific type of // object we're looking at. We only generate specialized // descriptions where we can. In all other cases, we emit the // generic info. static void GenerateObjectDesc(HeapObject* obj, char* buffer, int buffer_size) { Vector<char> buffer_v(buffer, buffer_size); ASSERT(obj != NULL); if (obj->IsJSArray()) { JSArray* jsarray = JSArray::cast(obj); double length = jsarray->length()->Number(); OS::SNPrintF(buffer_v, "%p <%s> len %g", reinterpret_cast<void*>(obj), GetObjectTypeDesc(obj), length); } else if (obj->IsString()) { String* str = String::cast(obj); // Only grab up to 160 chars in case they are double byte. // We'll only dump 80 of them after we compact them. const int kMaxCharToDump = 80; const int kMaxBufferSize = kMaxCharToDump * 2; SmartArrayPointer<char> str_sp = str->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL, 0, kMaxBufferSize); char* str_cstr = *str_sp; int length = CompactString(str_cstr); OS::SNPrintF(buffer_v, "%p <%s> '%.80s%s'", reinterpret_cast<void*>(obj), GetObjectTypeDesc(obj), str_cstr, (length > kMaxCharToDump) ? "..." : ""); } else if (obj->IsJSFunction() || obj->IsSharedFunctionInfo()) { SharedFunctionInfo* sinfo; if (obj->IsJSFunction()) { JSFunction* func = JSFunction::cast(obj); sinfo = func->shared(); } else { sinfo = SharedFunctionInfo::cast(obj); } String* name = sinfo->DebugName(); SmartArrayPointer<char> name_sp = name->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL); char* name_cstr = *name_sp; HeapStringAllocator string_allocator; StringStream stream(&string_allocator); sinfo->SourceCodePrint(&stream, 50); SmartArrayPointer<const char> source_sp = stream.ToCString(); const char* source_cstr = *source_sp; OS::SNPrintF(buffer_v, "%p <%s> '%s' %s", reinterpret_cast<void*>(obj), GetObjectTypeDesc(obj), name_cstr, source_cstr); } else if (obj->IsFixedArray()) { FixedArray* fixed = FixedArray::cast(obj); OS::SNPrintF(buffer_v, "%p <%s> len %d", reinterpret_cast<void*>(obj), GetObjectTypeDesc(obj), fixed->length()); } else { OS::SNPrintF(buffer_v, "%p <%s>", reinterpret_cast<void*>(obj), GetObjectTypeDesc(obj)); } } // Utility function for filling in a line of detail in a verbose dump. static bool AddObjDetail(Handle<FixedArray> arr, int index, int obj_id, Handle<HeapObject> target, const char* desc_str, Handle<String> id_sym, Handle<String> desc_sym, Handle<String> size_sym, Handle<JSObject> detail, Handle<String> desc, Handle<Object> error) { Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); detail = factory->NewJSObject(isolate->object_function()); if (detail->IsFailure()) { error = detail; return false; } int size = 0; char buffer[512]; if (desc_str == NULL) { ASSERT(!target.is_null()); HeapObject* obj = *target; GenerateObjectDesc(obj, buffer, sizeof(buffer)); desc_str = buffer; size = obj->Size(); } desc = factory->NewStringFromAscii(CStrVector(desc_str)); if (desc->IsFailure()) { error = desc; return false; } { MaybeObject* maybe_result = detail->SetProperty(*id_sym, Smi::FromInt(obj_id), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return false; } { MaybeObject* maybe_result = detail->SetProperty(*desc_sym, *desc, NONE, kNonStrictMode); if (maybe_result->IsFailure()) return false; } { MaybeObject* maybe_result = detail->SetProperty(*size_sym, Smi::FromInt(size), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return false; } arr->set(index, *detail); return true; } class DumpWriter { public: virtual ~DumpWriter() {} virtual void ComputeTotalCountAndSize(LolFilter* filter, int* count, int* size) = 0; virtual bool Write(Handle<FixedArray> elements_arr, int start, int dump_limit, LolFilter* filter, Handle<Object> error) = 0; }; class LolDumpWriter: public DumpWriter { public: LolDumpWriter(LiveObjectList* older, LiveObjectList* newer) : older_(older), newer_(newer) { } void ComputeTotalCountAndSize(LolFilter* filter, int* count, int* size) { *count = 0; *size = 0; LolIterator it(older_, newer_); for (it.Init(); !it.Done(); it.Next()) { HeapObject* heap_obj = it.Obj(); if (!filter->Matches(heap_obj)) { continue; } *size += heap_obj->Size(); (*count)++; } } bool Write(Handle<FixedArray> elements_arr, int start, int dump_limit, LolFilter* filter, Handle<Object> error) { // The lols are listed in latest to earliest. We want to dump from // earliest to latest. So, compute the last element to start with. int index = 0; int count = 0; Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); // Prefetch some needed symbols. Handle<String> id_sym = factory->LookupAsciiSymbol("id"); Handle<String> desc_sym = factory->LookupAsciiSymbol("desc"); Handle<String> size_sym = factory->LookupAsciiSymbol("size"); // Fill the array with the lol object details. Handle<JSObject> detail; Handle<String> desc; Handle<HeapObject> target; LiveObjectList* first_lol = (older_ != NULL) ? older_->next_ : LiveObjectList::first_; LiveObjectList* last_lol = (newer_ != NULL) ? newer_->next_ : NULL; LolForwardIterator it(first_lol, last_lol); for (it.Init(); !it.Done() && (index < dump_limit); it.Next()) { HeapObject* heap_obj = it.Obj(); // Skip objects that have been filtered out. if (!filter->Matches(heap_obj)) { continue; } // Only report objects that are in the section of interest. if (count >= start) { target = Handle<HeapObject>(heap_obj); bool success = AddObjDetail(elements_arr, index++, it.Id(), target, NULL, id_sym, desc_sym, size_sym, detail, desc, error); if (!success) return false; } count++; } return true; } private: LiveObjectList* older_; LiveObjectList* newer_; }; class RetainersDumpWriter: public DumpWriter { public: RetainersDumpWriter(Handle<HeapObject> target, Handle<JSObject> instance_filter, Handle<JSFunction> args_function) : target_(target), instance_filter_(instance_filter), args_function_(args_function) { } void ComputeTotalCountAndSize(LolFilter* filter, int* count, int* size) { Handle<FixedArray> retainers_arr; Handle<Object> error; *size = -1; LiveObjectList::GetRetainers(target_, instance_filter_, retainers_arr, 0, Smi::kMaxValue, count, filter, NULL, *args_function_, error); } bool Write(Handle<FixedArray> elements_arr, int start, int dump_limit, LolFilter* filter, Handle<Object> error) { int dummy; int count; // Fill the retainer objects. count = LiveObjectList::GetRetainers(target_, instance_filter_, elements_arr, start, dump_limit, &dummy, filter, NULL, *args_function_, error); if (count < 0) { return false; } return true; } private: Handle<HeapObject> target_; Handle<JSObject> instance_filter_; Handle<JSFunction> args_function_; }; class LiveObjectSummary { public: explicit LiveObjectSummary(LolFilter* filter) : total_count_(0), total_size_(0), found_root_(false), found_weak_root_(false), filter_(filter) { memset(counts_, 0, sizeof(counts_[0]) * kNumberOfEntries); memset(sizes_, 0, sizeof(sizes_[0]) * kNumberOfEntries); } void Add(HeapObject* heap_obj) { int size = heap_obj->Size(); LiveObjectType type = GetObjectType(heap_obj); ASSERT(type != kInvalidLiveObjType); counts_[type]++; sizes_[type] += size; total_count_++; total_size_ += size; } void set_found_root() { found_root_ = true; } void set_found_weak_root() { found_weak_root_ = true; } inline int Count(LiveObjectType type) { return counts_[type]; } inline int Size(LiveObjectType type) { return sizes_[type]; } inline int total_count() { return total_count_; } inline int total_size() { return total_size_; } inline bool found_root() { return found_root_; } inline bool found_weak_root() { return found_weak_root_; } int GetNumberOfEntries() { int entries = 0; for (int i = 0; i < kNumberOfEntries; i++) { if (counts_[i]) entries++; } return entries; } inline LolFilter* filter() { return filter_; } static const int kNumberOfEntries = kNumberOfTypes; private: int counts_[kNumberOfEntries]; int sizes_[kNumberOfEntries]; int total_count_; int total_size_; bool found_root_; bool found_weak_root_; LolFilter* filter_; }; // Abstraction for a summary writer. class SummaryWriter { public: virtual ~SummaryWriter() {} virtual void Write(LiveObjectSummary* summary) = 0; }; // A summary writer for filling in a summary of lol lists and diffs. class LolSummaryWriter: public SummaryWriter { public: LolSummaryWriter(LiveObjectList* older_lol, LiveObjectList* newer_lol) : older_(older_lol), newer_(newer_lol) { } void Write(LiveObjectSummary* summary) { LolFilter* filter = summary->filter(); // Fill the summary with the lol object details. LolIterator it(older_, newer_); for (it.Init(); !it.Done(); it.Next()) { HeapObject* heap_obj = it.Obj(); if (!filter->Matches(heap_obj)) { continue; } summary->Add(heap_obj); } } private: LiveObjectList* older_; LiveObjectList* newer_; }; // A summary writer for filling in a retainers list. class RetainersSummaryWriter: public SummaryWriter { public: RetainersSummaryWriter(Handle<HeapObject> target, Handle<JSObject> instance_filter, Handle<JSFunction> args_function) : target_(target), instance_filter_(instance_filter), args_function_(args_function) { } void Write(LiveObjectSummary* summary) { Handle<FixedArray> retainers_arr; Handle<Object> error; int dummy_total_count; LiveObjectList::GetRetainers(target_, instance_filter_, retainers_arr, 0, Smi::kMaxValue, &dummy_total_count, summary->filter(), summary, *args_function_, error); } private: Handle<HeapObject> target_; Handle<JSObject> instance_filter_; Handle<JSFunction> args_function_; }; uint32_t LiveObjectList::next_element_id_ = 1; int LiveObjectList::list_count_ = 0; int LiveObjectList::last_id_ = 0; LiveObjectList* LiveObjectList::first_ = NULL; LiveObjectList* LiveObjectList::last_ = NULL; LiveObjectList::LiveObjectList(LiveObjectList* prev, int capacity) : prev_(prev), next_(NULL), capacity_(capacity), obj_count_(0) { elements_ = NewArray<Element>(capacity); id_ = ++last_id_; list_count_++; } LiveObjectList::~LiveObjectList() { DeleteArray<Element>(elements_); delete prev_; } int LiveObjectList::GetTotalObjCountAndSize(int* size_p) { int size = 0; int count = 0; LiveObjectList* lol = this; do { // Only compute total size if requested i.e. when size_p is not null. if (size_p != NULL) { Element* elements = lol->elements_; for (int i = 0; i < lol->obj_count_; i++) { HeapObject* heap_obj = elements[i].obj_; size += heap_obj->Size(); } } count += lol->obj_count_; lol = lol->prev_; } while (lol != NULL); if (size_p != NULL) { *size_p = size; } return count; } // Adds an object to the lol. // Returns true if successful, else returns false. bool LiveObjectList::Add(HeapObject* obj) { // If the object is already accounted for in the prev list which we inherit // from, then no need to add it to this list. if ((prev() != NULL) && (prev()->Find(obj) != NULL)) { return true; } ASSERT(obj_count_ <= capacity_); if (obj_count_ == capacity_) { // The heap must have grown and we have more objects than capacity to store // them. return false; // Fail this addition. } Element& element = elements_[obj_count_++]; element.id_ = next_element_id_++; element.obj_ = obj; return true; } // Comparator used for sorting and searching the lol. int LiveObjectList::CompareElement(const Element* a, const Element* b) { const HeapObject* obj1 = a->obj_; const HeapObject* obj2 = b->obj_; // For lol elements, it doesn't matter which comes first if 2 elements point // to the same object (which gets culled later). Hence, we only care about // the the greater than / less than relationships. return (obj1 > obj2) ? 1 : (obj1 == obj2) ? 0 : -1; } // Looks for the specified object in the lol, and returns its element if found. LiveObjectList::Element* LiveObjectList::Find(HeapObject* obj) { LiveObjectList* lol = this; Element key; Element* result = NULL; key.obj_ = obj; // Iterate through the chain of lol's to look for the object. while ((result == NULL) && (lol != NULL)) { result = reinterpret_cast<Element*>( bsearch(&key, lol->elements_, lol->obj_count_, sizeof(Element), reinterpret_cast<RawComparer>(CompareElement))); lol = lol->prev_; } return result; } // "Nullifies" (convert the HeapObject* into an SMI) so that it will get cleaned // up in the GCEpilogue, while preserving the sort order of the lol. // NOTE: the lols need to be already sorted before NullifyMostRecent() is // called. void LiveObjectList::NullifyMostRecent(HeapObject* obj) { LiveObjectList* lol = last(); Element key; Element* result = NULL; key.obj_ = obj; // Iterate through the chain of lol's to look for the object. while (lol != NULL) { result = reinterpret_cast<Element*>( bsearch(&key, lol->elements_, lol->obj_count_, sizeof(Element), reinterpret_cast<RawComparer>(CompareElement))); if (result != NULL) { // Since there may be more than one (we are nullifying dup's after all), // find the first in the current lol, and nullify that. The lol should // be sorted already to make this easy (see the use of SortAll()). int i = result - lol->elements_; // NOTE: we sort the lol in increasing order. So, if an object has been // "nullified" (its lowest bit will be cleared to make it look like an // SMI), it would/should show up before the equivalent dups that have not // yet been "nullified". Hence, we should be searching backwards for the // first occurence of a matching object and nullify that instance. This // will ensure that we preserve the expected sorting order. for (i--; i > 0; i--) { Element* element = &lol->elements_[i]; HeapObject* curr_obj = element->obj_; if (curr_obj != obj) { break; // No more matches. Let's move on. } result = element; // Let this earlier match be the result. } // Nullify the object. NullifyNonLivePointer(&result->obj_); return; } lol = lol->prev_; } } // Sorts the lol. void LiveObjectList::Sort() { if (obj_count_ > 0) { Vector<Element> elements_v(elements_, obj_count_); elements_v.Sort(CompareElement); } } // Sorts all captured lols starting from the latest. void LiveObjectList::SortAll() { LiveObjectList* lol = last(); while (lol != NULL) { lol->Sort(); lol = lol->prev_; } } // Counts the number of objects in the heap. static int CountHeapObjects() { int count = 0; // Iterate over all the heap spaces and count the number of objects. HeapIterator iterator; HeapObject* heap_obj = NULL; while ((heap_obj = iterator.next()) != NULL) { count++; } return count; } // Captures a current snapshot of all objects in the heap. MaybeObject* LiveObjectList::Capture() { Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); HandleScope scope(isolate); // Count the number of objects in the heap. int total_count = CountHeapObjects(); int count = total_count; int size = 0; LiveObjectList* last_lol = last(); if (last_lol != NULL) { count -= last_lol->TotalObjCount(); } LiveObjectList* lol; // Create a lol large enough to track all the objects. lol = new LiveObjectList(last_lol, count); if (lol == NULL) { return NULL; // No memory to proceed. } // The HeapIterator needs to be in its own scope because it disables // allocation, and we need allocate below. { // Iterate over all the heap spaces and add the objects. HeapIterator iterator; HeapObject* heap_obj = NULL; bool failed = false; while (!failed && (heap_obj = iterator.next()) != NULL) { failed = !lol->Add(heap_obj); size += heap_obj->Size(); } ASSERT(!failed); lol->Sort(); // Add the current lol to the list of lols. if (last_ != NULL) { last_->next_ = lol; } else { first_ = lol; } last_ = lol; #ifdef VERIFY_LOL if (FLAG_verify_lol) { Verify(true); } #endif } Handle<String> id_sym = factory->LookupAsciiSymbol("id"); Handle<String> count_sym = factory->LookupAsciiSymbol("count"); Handle<String> size_sym = factory->LookupAsciiSymbol("size"); Handle<JSObject> result = factory->NewJSObject(isolate->object_function()); if (result->IsFailure()) return Object::cast(*result); { MaybeObject* maybe_result = result->SetProperty(*id_sym, Smi::FromInt(lol->id()), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; } { MaybeObject* maybe_result = result->SetProperty(*count_sym, Smi::FromInt(total_count), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; } { MaybeObject* maybe_result = result->SetProperty(*size_sym, Smi::FromInt(size), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; } return *result; } // Delete doesn't actually deletes an lol. It just marks it as invisible since // its contents are considered to be part of subsequent lists as well. The // only time we'll actually delete the lol is when we Reset() or if the lol is // invisible, and its element count reaches 0. bool LiveObjectList::Delete(int id) { LiveObjectList* lol = last(); while (lol != NULL) { if (lol->id() == id) { break; } lol = lol->prev_; } // If no lol is found for this id, then we fail to delete. if (lol == NULL) return false; // Else, mark the lol as invisible i.e. id == 0. lol->id_ = 0; list_count_--; ASSERT(list_count_ >= 0); if (lol->obj_count_ == 0) { // Point the next lol's prev to this lol's prev. LiveObjectList* next = lol->next_; LiveObjectList* prev = lol->prev_; // Point next's prev to prev. if (next != NULL) { next->prev_ = lol->prev_; } else { last_ = lol->prev_; } // Point prev's next to next. if (prev != NULL) { prev->next_ = lol->next_; } else { first_ = lol->next_; } lol->prev_ = NULL; lol->next_ = NULL; // Delete this now empty and invisible lol. delete lol; } // Just in case we've marked everything invisible, then clean up completely. if (list_count_ == 0) { Reset(); } return true; } MaybeObject* LiveObjectList::Dump(int older_id, int newer_id, int start_idx, int dump_limit, Handle<JSObject> filter_obj) { if ((older_id < 0) || (newer_id < 0) || (last() == NULL)) { return Failure::Exception(); // Fail: 0 is not a valid lol id. } if (newer_id < older_id) { // They are not in the expected order. Swap them. int temp = older_id; older_id = newer_id; newer_id = temp; } LiveObjectList* newer_lol = FindLolForId(newer_id, last()); LiveObjectList* older_lol = FindLolForId(older_id, newer_lol); // If the id is defined, and we can't find a LOL for it, then we have an // invalid id. if ((newer_id != 0) && (newer_lol == NULL)) { return Failure::Exception(); // Fail: the newer lol id is invalid. } if ((older_id != 0) && (older_lol == NULL)) { return Failure::Exception(); // Fail: the older lol id is invalid. } LolFilter filter(filter_obj); LolDumpWriter writer(older_lol, newer_lol); return DumpPrivate(&writer, start_idx, dump_limit, &filter); } MaybeObject* LiveObjectList::DumpPrivate(DumpWriter* writer, int start, int dump_limit, LolFilter* filter) { Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); HandleScope scope(isolate); // Calculate the number of entries of the dump. int count = -1; int size = -1; writer->ComputeTotalCountAndSize(filter, &count, &size); // Adjust for where to start the dump. if ((start < 0) || (start >= count)) { return Failure::Exception(); // invalid start. } int remaining_count = count - start; if (dump_limit > remaining_count) { dump_limit = remaining_count; } // Allocate an array to hold the result. Handle<FixedArray> elements_arr = factory->NewFixedArray(dump_limit); if (elements_arr->IsFailure()) return Object::cast(*elements_arr); // Fill in the dump. Handle<Object> error; bool success = writer->Write(elements_arr, start, dump_limit, filter, error); if (!success) return Object::cast(*error); MaybeObject* maybe_result; // Allocate the result body. Handle<JSObject> body = factory->NewJSObject(isolate->object_function()); if (body->IsFailure()) return Object::cast(*body); // Set the updated body.count. Handle<String> count_sym = factory->LookupAsciiSymbol("count"); maybe_result = body->SetProperty(*count_sym, Smi::FromInt(count), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; // Set the updated body.size if appropriate. if (size >= 0) { Handle<String> size_sym = factory->LookupAsciiSymbol("size"); maybe_result = body->SetProperty(*size_sym, Smi::FromInt(size), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; } // Set body.first_index. Handle<String> first_sym = factory->LookupAsciiSymbol("first_index"); maybe_result = body->SetProperty(*first_sym, Smi::FromInt(start), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; // Allocate the JSArray of the elements. Handle<JSObject> elements = factory->NewJSObject(isolate->array_function()); if (elements->IsFailure()) return Object::cast(*elements); maybe_result = Handle<JSArray>::cast(elements)->SetContent(*elements_arr); if (maybe_result->IsFailure()) return maybe_result; // Set body.elements. Handle<String> elements_sym = factory->LookupAsciiSymbol("elements"); maybe_result = body->SetProperty(*elements_sym, *elements, NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; return *body; } MaybeObject* LiveObjectList::Summarize(int older_id, int newer_id, Handle<JSObject> filter_obj) { if ((older_id < 0) || (newer_id < 0) || (last() == NULL)) { return Failure::Exception(); // Fail: 0 is not a valid lol id. } if (newer_id < older_id) { // They are not in the expected order. Swap them. int temp = older_id; older_id = newer_id; newer_id = temp; } LiveObjectList* newer_lol = FindLolForId(newer_id, last()); LiveObjectList* older_lol = FindLolForId(older_id, newer_lol); // If the id is defined, and we can't find a LOL for it, then we have an // invalid id. if ((newer_id != 0) && (newer_lol == NULL)) { return Failure::Exception(); // Fail: the newer lol id is invalid. } if ((older_id != 0) && (older_lol == NULL)) { return Failure::Exception(); // Fail: the older lol id is invalid. } LolFilter filter(filter_obj); LolSummaryWriter writer(older_lol, newer_lol); return SummarizePrivate(&writer, &filter, false); } // Creates a summary report for the debugger. // Note: the SummaryWriter takes care of iterating over objects and filling in // the summary. MaybeObject* LiveObjectList::SummarizePrivate(SummaryWriter* writer, LolFilter* filter, bool is_tracking_roots) { HandleScope scope; MaybeObject* maybe_result; LiveObjectSummary summary(filter); writer->Write(&summary); Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); // The result body will look like this: // body: { // count: <total_count>, // size: <total_size>, // found_root: <boolean>, // optional. // found_weak_root: <boolean>, // optional. // summary: [ // { // desc: "<object type name>", // count: <count>, // size: size // }, // ... // ] // } // Prefetch some needed symbols. Handle<String> desc_sym = factory->LookupAsciiSymbol("desc"); Handle<String> count_sym = factory->LookupAsciiSymbol("count"); Handle<String> size_sym = factory->LookupAsciiSymbol("size"); Handle<String> summary_sym = factory->LookupAsciiSymbol("summary"); // Allocate the summary array. int entries_count = summary.GetNumberOfEntries(); Handle<FixedArray> summary_arr = factory->NewFixedArray(entries_count); if (summary_arr->IsFailure()) return Object::cast(*summary_arr); int idx = 0; for (int i = 0; i < LiveObjectSummary::kNumberOfEntries; i++) { // Allocate the summary record. Handle<JSObject> detail = factory->NewJSObject(isolate->object_function()); if (detail->IsFailure()) return Object::cast(*detail); // Fill in the summary record. LiveObjectType type = static_cast<LiveObjectType>(i); int count = summary.Count(type); if (count) { const char* desc_cstr = GetObjectTypeDesc(type); Handle<String> desc = factory->LookupAsciiSymbol(desc_cstr); int size = summary.Size(type); maybe_result = detail->SetProperty(*desc_sym, *desc, NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; maybe_result = detail->SetProperty(*count_sym, Smi::FromInt(count), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; maybe_result = detail->SetProperty(*size_sym, Smi::FromInt(size), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; summary_arr->set(idx++, *detail); } } // Wrap the summary fixed array in a JS array. Handle<JSObject> summary_obj = factory->NewJSObject(isolate->array_function()); if (summary_obj->IsFailure()) return Object::cast(*summary_obj); maybe_result = Handle<JSArray>::cast(summary_obj)->SetContent(*summary_arr); if (maybe_result->IsFailure()) return maybe_result; // Create the body object. Handle<JSObject> body = factory->NewJSObject(isolate->object_function()); if (body->IsFailure()) return Object::cast(*body); // Fill out the body object. int total_count = summary.total_count(); int total_size = summary.total_size(); maybe_result = body->SetProperty(*count_sym, Smi::FromInt(total_count), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; maybe_result = body->SetProperty(*size_sym, Smi::FromInt(total_size), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; if (is_tracking_roots) { int found_root = summary.found_root(); int found_weak_root = summary.found_weak_root(); Handle<String> root_sym = factory->LookupAsciiSymbol("found_root"); Handle<String> weak_root_sym = factory->LookupAsciiSymbol("found_weak_root"); maybe_result = body->SetProperty(*root_sym, Smi::FromInt(found_root), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; maybe_result = body->SetProperty(*weak_root_sym, Smi::FromInt(found_weak_root), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; } maybe_result = body->SetProperty(*summary_sym, *summary_obj, NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; return *body; } // Returns an array listing the captured lols. // Note: only dumps the section starting at start_idx and only up to // dump_limit entries. MaybeObject* LiveObjectList::Info(int start_idx, int dump_limit) { Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); HandleScope scope(isolate); MaybeObject* maybe_result; int total_count = LiveObjectList::list_count(); int dump_count = total_count; // Adjust for where to start the dump. if (total_count == 0) { start_idx = 0; // Ensure this to get an empty list. } else if ((start_idx < 0) || (start_idx >= total_count)) { return Failure::Exception(); // invalid start. } dump_count -= start_idx; // Adjust for the dump limit. if (dump_count > dump_limit) { dump_count = dump_limit; } // Allocate an array to hold the result. Handle<FixedArray> list = factory->NewFixedArray(dump_count); if (list->IsFailure()) return Object::cast(*list); // Prefetch some needed symbols. Handle<String> id_sym = factory->LookupAsciiSymbol("id"); Handle<String> count_sym = factory->LookupAsciiSymbol("count"); Handle<String> size_sym = factory->LookupAsciiSymbol("size"); // Fill the array with the lol details. int idx = 0; LiveObjectList* lol = first_; while ((lol != NULL) && (idx < start_idx)) { // Skip tail entries. if (lol->id() != 0) { idx++; } lol = lol->next(); } idx = 0; while ((lol != NULL) && (dump_limit != 0)) { if (lol->id() != 0) { int count; int size; count = lol->GetTotalObjCountAndSize(&size); Handle<JSObject> detail = factory->NewJSObject(isolate->object_function()); if (detail->IsFailure()) return Object::cast(*detail); maybe_result = detail->SetProperty(*id_sym, Smi::FromInt(lol->id()), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; maybe_result = detail->SetProperty(*count_sym, Smi::FromInt(count), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; maybe_result = detail->SetProperty(*size_sym, Smi::FromInt(size), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; list->set(idx++, *detail); dump_limit--; } lol = lol->next(); } // Return the result as a JS array. Handle<JSObject> lols = factory->NewJSObject(isolate->array_function()); maybe_result = Handle<JSArray>::cast(lols)->SetContent(*list); if (maybe_result->IsFailure()) return maybe_result; Handle<JSObject> result = factory->NewJSObject(isolate->object_function()); if (result->IsFailure()) return Object::cast(*result); maybe_result = result->SetProperty(*count_sym, Smi::FromInt(total_count), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; Handle<String> first_sym = factory->LookupAsciiSymbol("first_index"); maybe_result = result->SetProperty(*first_sym, Smi::FromInt(start_idx), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; Handle<String> lists_sym = factory->LookupAsciiSymbol("lists"); maybe_result = result->SetProperty(*lists_sym, *lols, NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; return *result; } // Deletes all captured lols. void LiveObjectList::Reset() { LiveObjectList* lol = last(); // Just delete the last. Each lol will delete it's prev automatically. delete lol; next_element_id_ = 1; list_count_ = 0; last_id_ = 0; first_ = NULL; last_ = NULL; } // Gets the object for the specified obj id. Object* LiveObjectList::GetObj(int obj_id) { Element* element = FindElementFor<int>(GetElementId, obj_id); if (element != NULL) { return Object::cast(element->obj_); } return HEAP->undefined_value(); } // Gets the obj id for the specified address if valid. int LiveObjectList::GetObjId(Object* obj) { // Make a heap object pointer from the address. HeapObject* hobj = HeapObject::cast(obj); Element* element = FindElementFor<HeapObject*>(GetElementObj, hobj); if (element != NULL) { return element->id_; } return 0; // Invalid address. } // Gets the obj id for the specified address if valid. Object* LiveObjectList::GetObjId(Handle<String> address) { SmartArrayPointer<char> addr_str = address->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL); Isolate* isolate = Isolate::Current(); // Extract the address value from the string. int value = static_cast<int>(StringToInt(isolate->unicode_cache(), *address, 16)); Object* obj = reinterpret_cast<Object*>(value); return Smi::FromInt(GetObjId(obj)); } // Helper class for copying HeapObjects. class LolVisitor: public ObjectVisitor { public: LolVisitor(HeapObject* target, Handle<HeapObject> handle_to_skip) : target_(target), handle_to_skip_(handle_to_skip), found_(false) {} void VisitPointer(Object** p) { CheckPointer(p); } void VisitPointers(Object** start, Object** end) { // Check all HeapObject pointers in [start, end). for (Object** p = start; !found() && p < end; p++) CheckPointer(p); } inline bool found() const { return found_; } inline bool reset() { return found_ = false; } private: inline void CheckPointer(Object** p) { Object* object = *p; if (HeapObject::cast(object) == target_) { // We may want to skip this handle because the handle may be a local // handle in a handle scope in one of our callers. Once we return, // that handle will be popped. Hence, we don't want to count it as // a root that would have kept the target object alive. if (!handle_to_skip_.is_null() && handle_to_skip_.location() == reinterpret_cast<HeapObject**>(p)) { return; // Skip this handle. } found_ = true; } } HeapObject* target_; Handle<HeapObject> handle_to_skip_; bool found_; }; inline bool AddRootRetainerIfFound(const LolVisitor& visitor, LolFilter* filter, LiveObjectSummary* summary, void (*SetRootFound)(LiveObjectSummary* s), int start, int dump_limit, int* total_count, Handle<FixedArray> retainers_arr, int* count, int* index, const char* root_name, Handle<String> id_sym, Handle<String> desc_sym, Handle<String> size_sym, Handle<Object> error) { HandleScope scope; // Scratch handles. Handle<JSObject> detail; Handle<String> desc; Handle<HeapObject> retainer; if (visitor.found()) { if (!filter->is_active()) { (*total_count)++; if (summary) { SetRootFound(summary); } else if ((*total_count > start) && ((*index) < dump_limit)) { (*count)++; if (!retainers_arr.is_null()) { return AddObjDetail(retainers_arr, (*index)++, 0, retainer, root_name, id_sym, desc_sym, size_sym, detail, desc, error); } } } } return true; } inline void SetFoundRoot(LiveObjectSummary* summary) { summary->set_found_root(); } inline void SetFoundWeakRoot(LiveObjectSummary* summary) { summary->set_found_weak_root(); } int LiveObjectList::GetRetainers(Handle<HeapObject> target, Handle<JSObject> instance_filter, Handle<FixedArray> retainers_arr, int start, int dump_limit, int* total_count, LolFilter* filter, LiveObjectSummary* summary, JSFunction* arguments_function, Handle<Object> error) { HandleScope scope; // Scratch handles. Handle<JSObject> detail; Handle<String> desc; Handle<HeapObject> retainer; Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); // Prefetch some needed symbols. Handle<String> id_sym = factory->LookupAsciiSymbol("id"); Handle<String> desc_sym = factory->LookupAsciiSymbol("desc"); Handle<String> size_sym = factory->LookupAsciiSymbol("size"); NoHandleAllocation ha; int count = 0; int index = 0; Handle<JSObject> last_obj; *total_count = 0; // Iterate roots. LolVisitor lol_visitor(*target, target); isolate->heap()->IterateStrongRoots(&lol_visitor, VISIT_ALL); if (!AddRootRetainerIfFound(lol_visitor, filter, summary, SetFoundRoot, start, dump_limit, total_count, retainers_arr, &count, &index, "<root>", id_sym, desc_sym, size_sym, error)) { return -1; } lol_visitor.reset(); isolate->heap()->IterateWeakRoots(&lol_visitor, VISIT_ALL); if (!AddRootRetainerIfFound(lol_visitor, filter, summary, SetFoundWeakRoot, start, dump_limit, total_count, retainers_arr, &count, &index, "<weak root>", id_sym, desc_sym, size_sym, error)) { return -1; } // Iterate the live object lists. LolIterator it(NULL, last()); for (it.Init(); !it.Done() && (index < dump_limit); it.Next()) { HeapObject* heap_obj = it.Obj(); // Only look at all JSObjects. if (heap_obj->IsJSObject()) { // Skip context extension objects and argument arrays as these are // checked in the context of functions using them. JSObject* obj = JSObject::cast(heap_obj); if (obj->IsJSContextExtensionObject() || obj->map()->constructor() == arguments_function) { continue; } // Check if the JS object has a reference to the object looked for. if (obj->ReferencesObject(*target)) { // Check instance filter if supplied. This is normally used to avoid // references from mirror objects (see Runtime_IsInPrototypeChain). if (!instance_filter->IsUndefined()) { Object* V = obj; while (true) { Object* prototype = V->GetPrototype(); if (prototype->IsNull()) { break; } if (*instance_filter == prototype) { obj = NULL; // Don't add this object. break; } V = prototype; } } if (obj != NULL) { // Skip objects that have been filtered out. if (filter->Matches(heap_obj)) { continue; } // Valid reference found add to instance array if supplied an update // count. last_obj = Handle<JSObject>(obj); (*total_count)++; if (summary != NULL) { summary->Add(heap_obj); } else if ((*total_count > start) && (index < dump_limit)) { count++; if (!retainers_arr.is_null()) { retainer = Handle<HeapObject>(heap_obj); bool success = AddObjDetail(retainers_arr, index++, it.Id(), retainer, NULL, id_sym, desc_sym, size_sym, detail, desc, error); if (!success) return -1; } } } } } } // Check for circular reference only. This can happen when the object is only // referenced from mirrors and has a circular reference in which case the // object is not really alive and would have been garbage collected if not // referenced from the mirror. if (*total_count == 1 && !last_obj.is_null() && *last_obj == *target) { count = 0; *total_count = 0; } return count; } MaybeObject* LiveObjectList::GetObjRetainers(int obj_id, Handle<JSObject> instance_filter, bool verbose, int start, int dump_limit, Handle<JSObject> filter_obj) { Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); Heap* heap = isolate->heap(); HandleScope scope(isolate); // Get the target object. HeapObject* heap_obj = HeapObject::cast(GetObj(obj_id)); if (heap_obj == heap->undefined_value()) { return heap_obj; } Handle<HeapObject> target = Handle<HeapObject>(heap_obj); // Get the constructor function for context extension and arguments array. JSObject* arguments_boilerplate = isolate->context()->global_context()->arguments_boilerplate(); JSFunction* arguments_function = JSFunction::cast(arguments_boilerplate->map()->constructor()); Handle<JSFunction> args_function = Handle<JSFunction>(arguments_function); LolFilter filter(filter_obj); if (!verbose) { RetainersSummaryWriter writer(target, instance_filter, args_function); return SummarizePrivate(&writer, &filter, true); } else { RetainersDumpWriter writer(target, instance_filter, args_function); Object* body_obj; MaybeObject* maybe_result = DumpPrivate(&writer, start, dump_limit, &filter); if (!maybe_result->ToObject(&body_obj)) { return maybe_result; } // Set body.id. Handle<JSObject> body = Handle<JSObject>(JSObject::cast(body_obj)); Handle<String> id_sym = factory->LookupAsciiSymbol("id"); maybe_result = body->SetProperty(*id_sym, Smi::FromInt(obj_id), NONE, kNonStrictMode); if (maybe_result->IsFailure()) return maybe_result; return *body; } } Object* LiveObjectList::PrintObj(int obj_id) { Object* obj = GetObj(obj_id); if (!obj) { return HEAP->undefined_value(); } EmbeddedVector<char, 128> temp_filename; static int temp_count = 0; const char* path_prefix = "."; Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); Heap* heap = isolate->heap(); if (FLAG_lol_workdir) { path_prefix = FLAG_lol_workdir; } OS::SNPrintF(temp_filename, "%s/lol-print-%d", path_prefix, ++temp_count); FILE* f = OS::FOpen(temp_filename.start(), "w+"); PrintF(f, "@%d ", LiveObjectList::GetObjId(obj)); #ifdef OBJECT_PRINT #ifdef INSPECTOR Inspector::DumpObjectType(f, obj); #endif // INSPECTOR PrintF(f, "\n"); obj->Print(f); #else // !OBJECT_PRINT obj->ShortPrint(f); #endif // !OBJECT_PRINT PrintF(f, "\n"); Flush(f); fclose(f); // Create a string from the temp_file. // Note: the mmapped resource will take care of closing the file. MemoryMappedExternalResource* resource = new MemoryMappedExternalResource(temp_filename.start(), true); if (resource->exists() && !resource->is_empty()) { ASSERT(resource->IsAscii()); Handle<String> dump_string = factory->NewExternalStringFromAscii(resource); heap->external_string_table()->AddString(*dump_string); return *dump_string; } else { delete resource; } return HEAP->undefined_value(); } class LolPathTracer: public PathTracer { public: LolPathTracer(FILE* out, Object* search_target, WhatToFind what_to_find) : PathTracer(search_target, what_to_find, VISIT_ONLY_STRONG), out_(out) {} private: void ProcessResults(); FILE* out_; }; void LolPathTracer::ProcessResults() { if (found_target_) { PrintF(out_, "=====================================\n"); PrintF(out_, "==== Path to object ====\n"); PrintF(out_, "=====================================\n\n"); ASSERT(!object_stack_.is_empty()); Object* prev = NULL; for (int i = 0, index = 0; i < object_stack_.length(); i++) { Object* obj = object_stack_[i]; // Skip this object if it is basically the internals of the // previous object (which would have dumped its details already). if (prev && prev->IsJSObject() && (obj != search_target_)) { JSObject* jsobj = JSObject::cast(prev); if (obj->IsFixedArray() && jsobj->properties() == FixedArray::cast(obj)) { // Skip this one because it would have been printed as the // properties of the last object already. continue; } else if (obj->IsHeapObject() && jsobj->elements() == HeapObject::cast(obj)) { // Skip this one because it would have been printed as the // elements of the last object already. continue; } } // Print a connecting arrow. if (i > 0) PrintF(out_, "\n |\n |\n V\n\n"); // Print the object index. PrintF(out_, "[%d] ", ++index); // Print the LOL object ID: int id = LiveObjectList::GetObjId(obj); if (id > 0) PrintF(out_, "@%d ", id); #ifdef OBJECT_PRINT #ifdef INSPECTOR Inspector::DumpObjectType(out_, obj); #endif // INSPECTOR PrintF(out_, "\n"); obj->Print(out_); #else // !OBJECT_PRINT obj->ShortPrint(out_); PrintF(out_, "\n"); #endif // !OBJECT_PRINT Flush(out_); } PrintF(out_, "\n"); PrintF(out_, "=====================================\n\n"); Flush(out_); } } Object* LiveObjectList::GetPathPrivate(HeapObject* obj1, HeapObject* obj2) { EmbeddedVector<char, 128> temp_filename; static int temp_count = 0; const char* path_prefix = "."; if (FLAG_lol_workdir) { path_prefix = FLAG_lol_workdir; } OS::SNPrintF(temp_filename, "%s/lol-getpath-%d", path_prefix, ++temp_count); FILE* f = OS::FOpen(temp_filename.start(), "w+"); Isolate* isolate = Isolate::Current(); Factory* factory = isolate->factory(); Heap* heap = isolate->heap(); // Save the previous verbosity. bool prev_verbosity = FLAG_use_verbose_printer; FLAG_use_verbose_printer = false; // Dump the paths. { // The tracer needs to be scoped because its usage asserts no allocation, // and we need to allocate the result string below. LolPathTracer tracer(f, obj2, LolPathTracer::FIND_FIRST); bool found = false; if (obj1 == NULL) { // Check for ObjectGroups that references this object. // TODO(mlam): refactor this to be more modular. { List<ObjectGroup*>* groups = isolate->global_handles()->object_groups(); for (int i = 0; i < groups->length(); i++) { ObjectGroup* group = groups->at(i); if (group == NULL) continue; bool found_group = false; for (size_t j = 0; j < group->length_; j++) { Object* object = *(group->objects_[j]); HeapObject* hobj = HeapObject::cast(object); if (obj2 == hobj) { found_group = true; break; } } if (found_group) { PrintF(f, "obj %p is a member of object group %p {\n", reinterpret_cast<void*>(obj2), reinterpret_cast<void*>(group)); for (size_t j = 0; j < group->length_; j++) { Object* object = *(group->objects_[j]); if (!object->IsHeapObject()) continue; HeapObject* hobj = HeapObject::cast(object); int id = GetObjId(hobj); if (id != 0) { PrintF(f, " @%d:", id); } else { PrintF(f, " <no id>:"); } char buffer[512]; GenerateObjectDesc(hobj, buffer, sizeof(buffer)); PrintF(f, " %s", buffer); if (hobj == obj2) { PrintF(f, " <==="); } PrintF(f, "\n"); } PrintF(f, "}\n"); } } } PrintF(f, "path from roots to obj %p\n", reinterpret_cast<void*>(obj2)); heap->IterateRoots(&tracer, VISIT_ONLY_STRONG); found = tracer.found(); if (!found) { PrintF(f, " No paths found. Checking symbol tables ...\n"); SymbolTable* symbol_table = HEAP->raw_unchecked_symbol_table(); tracer.VisitPointers(reinterpret_cast<Object**>(&symbol_table), reinterpret_cast<Object**>(&symbol_table)+1); found = tracer.found(); if (!found) { symbol_table->IteratePrefix(&tracer); found = tracer.found(); } } if (!found) { PrintF(f, " No paths found. Checking weak roots ...\n"); // Check weak refs next. isolate->global_handles()->IterateWeakRoots(&tracer); found = tracer.found(); } } else { PrintF(f, "path from obj %p to obj %p:\n", reinterpret_cast<void*>(obj1), reinterpret_cast<void*>(obj2)); tracer.TracePathFrom(reinterpret_cast<Object**>(&obj1)); found = tracer.found(); } if (!found) { PrintF(f, " No paths found\n\n"); } } // Flush and clean up the dumped file. Flush(f); fclose(f); // Restore the previous verbosity. FLAG_use_verbose_printer = prev_verbosity; // Create a string from the temp_file. // Note: the mmapped resource will take care of closing the file. MemoryMappedExternalResource* resource = new MemoryMappedExternalResource(temp_filename.start(), true); if (resource->exists() && !resource->is_empty()) { ASSERT(resource->IsAscii()); Handle<String> path_string = factory->NewExternalStringFromAscii(resource); heap->external_string_table()->AddString(*path_string); return *path_string; } else { delete resource; } return heap->undefined_value(); } Object* LiveObjectList::GetPath(int obj_id1, int obj_id2, Handle<JSObject> instance_filter) { HandleScope scope; // Get the target object. HeapObject* obj1 = NULL; if (obj_id1 != 0) { obj1 = HeapObject::cast(GetObj(obj_id1)); if (obj1 == HEAP->undefined_value()) { return obj1; } } HeapObject* obj2 = HeapObject::cast(GetObj(obj_id2)); if (obj2 == HEAP->undefined_value()) { return obj2; } return GetPathPrivate(obj1, obj2); } void LiveObjectList::DoProcessNonLive(HeapObject* obj) { // We should only be called if we have at least one lol to search. ASSERT(last() != NULL); Element* element = last()->Find(obj); if (element != NULL) { NullifyNonLivePointer(&element->obj_); } } void LiveObjectList::IterateElementsPrivate(ObjectVisitor* v) { LiveObjectList* lol = last(); while (lol != NULL) { Element* elements = lol->elements_; int count = lol->obj_count_; for (int i = 0; i < count; i++) { HeapObject** p = &elements[i].obj_; v->VisitPointer(reinterpret_cast<Object** >(p)); } lol = lol->prev_; } } // Purpose: Called by GCEpilogue to purge duplicates. Not to be called by // anyone else. void LiveObjectList::PurgeDuplicates() { bool is_sorted = false; LiveObjectList* lol = last(); if (!lol) { return; // Nothing to purge. } int total_count = lol->TotalObjCount(); if (!total_count) { return; // Nothing to purge. } Element* elements = NewArray<Element>(total_count); int count = 0; // Copy all the object elements into a consecutive array. while (lol) { memcpy(&elements[count], lol->elements_, lol->obj_count_ * sizeof(Element)); count += lol->obj_count_; lol = lol->prev_; } qsort(elements, total_count, sizeof(Element), reinterpret_cast<RawComparer>(CompareElement)); ASSERT(count == total_count); // Iterate over all objects in the consolidated list and check for dups. total_count--; for (int i = 0; i < total_count; ) { Element* curr = &elements[i]; HeapObject* curr_obj = curr->obj_; int j = i+1; bool done = false; while (!done && (j < total_count)) { // Process if the element's object is still live after the current GC. // Non-live objects will be converted to SMIs i.e. not HeapObjects. if (curr_obj->IsHeapObject()) { Element* next = &elements[j]; HeapObject* next_obj = next->obj_; if (next_obj->IsHeapObject()) { if (curr_obj != next_obj) { done = true; continue; // Live object but no match. Move on. } // NOTE: we've just GCed the LOLs. Hence, they are no longer sorted. // Since we detected at least one need to search for entries, we'll // sort it to enable the use of NullifyMostRecent() below. We only // need to sort it once (except for one exception ... see below). if (!is_sorted) { SortAll(); is_sorted = true; } // We have a match. Need to nullify the most recent ref to this // object. We'll keep the oldest ref: // Note: we will nullify the element record in the LOL // database, not in the local sorted copy of the elements. NullifyMostRecent(curr_obj); } } // Either the object was already marked for purging, or we just marked // it. Either way, if there's more than one dup, then we need to check // the next element for another possible dup against the current as well // before we move on. So, here we go. j++; } // We can move on to checking the match on the next element. i = j; } DeleteArray<Element>(elements); } // Purpose: Purges dead objects and resorts the LOLs. void LiveObjectList::GCEpiloguePrivate() { // Note: During the GC, ConsStrings may be collected and pointers may be // forwarded to its constituent string. As a result, we may find dupes of // objects references in the LOL list. // Another common way we get dups is that free chunks that have been swept // in the oldGen heap may be kept as ByteArray objects in a free list. // // When we promote live objects from the youngGen, the object may be moved // to the start of these free chunks. Since there is no free or move event // for the free chunks, their addresses will show up 2 times: once for their // original free ByteArray selves, and once for the newly promoted youngGen // object. Hence, we can get a duplicate address in the LOL again. // // We need to eliminate these dups because the LOL implementation expects to // only have at most one unique LOL reference to any object at any time. PurgeDuplicates(); // After the GC, sweep away all free'd Elements and compact. LiveObjectList* prev = NULL; LiveObjectList* next = NULL; // Iterating from the youngest lol to the oldest lol. for (LiveObjectList* lol = last(); lol; lol = prev) { Element* elements = lol->elements_; prev = lol->prev(); // Save the prev. // Remove any references to collected objects. int i = 0; while (i < lol->obj_count_) { Element& element = elements[i]; if (!element.obj_->IsHeapObject()) { // If the HeapObject address was converted into a SMI, then this // is a dead object. Copy the last element over this one. element = elements[lol->obj_count_ - 1]; lol->obj_count_--; // We've just moved the last element into this index. We'll revisit // this index again. Hence, no need to increment the iterator. } else { i++; // Look at the next element next. } } int new_count = lol->obj_count_; // Check if there are any more elements to keep after purging the dead ones. if (new_count == 0) { DeleteArray<Element>(elements); lol->elements_ = NULL; lol->capacity_ = 0; ASSERT(lol->obj_count_ == 0); // If the list is also invisible, the clean up the list as well. if (lol->id_ == 0) { // Point the next lol's prev to this lol's prev. if (next) { next->prev_ = lol->prev_; } else { last_ = lol->prev_; } // Delete this now empty and invisible lol. delete lol; // Don't point the next to this lol since it is now deleted. // Leave the next pointer pointing to the current lol. continue; } } else { // If the obj_count_ is less than the capacity and the difference is // greater than a specified threshold, then we should shrink the list. int diff = lol->capacity_ - new_count; const int kMaxUnusedSpace = 64; if (diff > kMaxUnusedSpace) { // Threshold for shrinking. // Shrink the list. Element* new_elements = NewArray<Element>(new_count); memcpy(new_elements, elements, new_count * sizeof(Element)); DeleteArray<Element>(elements); lol->elements_ = new_elements; lol->capacity_ = new_count; } ASSERT(lol->obj_count_ == new_count); lol->Sort(); // We've moved objects. Re-sort in case. } // Save the next (for the previous link) in case we need it later. next = lol; } #ifdef VERIFY_LOL if (FLAG_verify_lol) { Verify(); } #endif } #ifdef VERIFY_LOL void LiveObjectList::Verify(bool match_heap_exactly) { OS::Print("Verifying the LiveObjectList database:\n"); LiveObjectList* lol = last(); if (lol == NULL) { OS::Print(" No lol database to verify\n"); return; } OS::Print(" Preparing the lol database ...\n"); int total_count = lol->TotalObjCount(); Element* elements = NewArray<Element>(total_count); int count = 0; // Copy all the object elements into a consecutive array. OS::Print(" Copying the lol database ...\n"); while (lol != NULL) { memcpy(&elements[count], lol->elements_, lol->obj_count_ * sizeof(Element)); count += lol->obj_count_; lol = lol->prev_; } qsort(elements, total_count, sizeof(Element), reinterpret_cast<RawComparer>(CompareElement)); ASSERT(count == total_count); // Iterate over all objects in the heap and check for: // 1. object in LOL but not in heap i.e. error. // 2. object in heap but not in LOL (possibly not an error). Usually // just means that we don't have the a capture of the latest heap. // That is unless we did this verify immediately after a capture, // and specified match_heap_exactly = true. int number_of_heap_objects = 0; int number_of_matches = 0; int number_not_in_heap = total_count; int number_not_in_lol = 0; OS::Print(" Start verify ...\n"); OS::Print(" Verifying ..."); Flush(); HeapIterator iterator; HeapObject* heap_obj = NULL; while ((heap_obj = iterator.next()) != NULL) { number_of_heap_objects++; // Check if the heap_obj is in the lol. Element key; key.obj_ = heap_obj; Element* result = reinterpret_cast<Element*>( bsearch(&key, elements, total_count, sizeof(Element), reinterpret_cast<RawComparer>(CompareElement))); if (result != NULL) { number_of_matches++; number_not_in_heap--; // Mark it as found by changing it into a SMI (mask off low bit). // Note: we cannot use HeapObject::cast() here because it asserts that // the HeapObject bit is set on the address, but we're unsetting it on // purpose here for our marking. result->obj_ = reinterpret_cast<HeapObject*>(heap_obj->address()); } else { number_not_in_lol++; if (match_heap_exactly) { OS::Print("heap object %p NOT in lol database\n", heap_obj); } } // Show some sign of life. if (number_of_heap_objects % 1000 == 0) { OS::Print("."); fflush(stdout); } } OS::Print("\n"); // Reporting lol objects not found in the heap. if (number_not_in_heap) { int found = 0; for (int i = 0; (i < total_count) && (found < number_not_in_heap); i++) { Element& element = elements[i]; if (element.obj_->IsHeapObject()) { OS::Print("lol database object [%d of %d] %p NOT in heap\n", i, total_count, element.obj_); found++; } } } DeleteArray<Element>(elements); OS::Print("number of objects in lol database %d\n", total_count); OS::Print("number of heap objects .......... %d\n", number_of_heap_objects); OS::Print("number of matches ............... %d\n", number_of_matches); OS::Print("number NOT in heap .............. %d\n", number_not_in_heap); OS::Print("number NOT in lol database ...... %d\n", number_not_in_lol); if (number_of_matches != total_count) { OS::Print(" *** ERROR: " "NOT all lol database objects match heap objects.\n"); } if (number_not_in_heap != 0) { OS::Print(" *** ERROR: %d lol database objects not found in heap.\n", number_not_in_heap); } if (match_heap_exactly) { if (!(number_not_in_lol == 0)) { OS::Print(" *** ERROR: %d heap objects NOT found in lol database.\n", number_not_in_lol); } } ASSERT(number_of_matches == total_count); ASSERT(number_not_in_heap == 0); ASSERT(number_not_in_lol == (number_of_heap_objects - total_count)); if (match_heap_exactly) { ASSERT(total_count == number_of_heap_objects); ASSERT(number_not_in_lol == 0); } OS::Print(" Verify the lol database is sorted ...\n"); lol = last(); while (lol != NULL) { Element* elements = lol->elements_; for (int i = 0; i < lol->obj_count_ - 1; i++) { if (elements[i].obj_ >= elements[i+1].obj_) { OS::Print(" *** ERROR: lol %p obj[%d] %p > obj[%d] %p\n", lol, i, elements[i].obj_, i+1, elements[i+1].obj_); } } lol = lol->prev_; } OS::Print(" DONE verifying.\n\n\n"); } void LiveObjectList::VerifyNotInFromSpace() { OS::Print("VerifyNotInFromSpace() ...\n"); LolIterator it(NULL, last()); Heap* heap = ISOLATE->heap(); int i = 0; for (it.Init(); !it.Done(); it.Next()) { HeapObject* heap_obj = it.Obj(); if (heap->InFromSpace(heap_obj)) { OS::Print(" ERROR: VerifyNotInFromSpace: [%d] obj %p in From space %p\n", i++, heap_obj, Heap::new_space()->FromSpaceStart()); } } } #endif // VERIFY_LOL } } // namespace v8::internal #endif // LIVE_OBJECT_LIST