[heap] Remove MemoryChunk::FromAnyPointerAddress

This function was only used for the write barrier since the store
buffer only stored slots and needed a way to get to the object's start.
Now that we insert into the remembered set directly from the write
barrier this isn't an issue anymore: the write barrier knows the
object start.

Change-Id: I701465ea40b7c4ee20404ecbcf3750e5fa6fd219
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1876049
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64518}

src/heap/basic-memory-chunk.cc

@@ -27,23 +27,12 @@ STATIC_ASSERT(BasicMemoryChunk::kHeapOffset ==
 
 BasicMemoryChunk::BasicMemoryChunk(size_t size, Address area_start,
                                    Address area_end) {
-  const Address base = reinterpret_cast<Address>(this);
   size_ = size;
   marking_bitmap_ = static_cast<Bitmap*>(calloc(1, Bitmap::kSize));
-  header_sentinel_ = HeapObject::FromAddress(base).ptr();
-  DCHECK(HasHeaderSentinel(area_start));
   area_start_ = area_start;
   area_end_ = area_end;
 }
 
-// static
-bool BasicMemoryChunk::HasHeaderSentinel(Address slot_addr) {
-  Address base = BaseAddress(slot_addr);
-  if (slot_addr < base + kHeaderSize) return false;
-  return HeapObject::FromAddress(base) ==
-         ObjectSlot(base + kHeaderSentinelOffset).Relaxed_Load();
-}
-
 void BasicMemoryChunk::ReleaseMarkingBitmap() {
   DCHECK_NOT_NULL(marking_bitmap_);
   free(marking_bitmap_);

src/heap/basic-memory-chunk.h

@@ -167,18 +167,13 @@ class BasicMemoryChunk {
     return addr >= area_start() && addr <= area_end();
   }
 
-  V8_EXPORT_PRIVATE static bool HasHeaderSentinel(Address slot_addr);
-
   void ReleaseMarkingBitmap();
 
   static const intptr_t kSizeOffset = 0;
   static const intptr_t kFlagsOffset = kSizeOffset + kSizetSize;
   static const intptr_t kMarkBitmapOffset = kFlagsOffset + kUIntptrSize;
   static const intptr_t kHeapOffset = kMarkBitmapOffset + kSystemPointerSize;
-  static const intptr_t kHeaderSentinelOffset =
-      kHeapOffset + kSystemPointerSize;
-  static const intptr_t kAreaStartOffset =
-      kHeaderSentinelOffset + kSystemPointerSize;
+  static const intptr_t kAreaStartOffset = kHeapOffset + kSystemPointerSize;
   static const intptr_t kAreaEndOffset = kAreaStartOffset + kSystemPointerSize;
   static const intptr_t kOldToNewSlotSetOffset =
       kAreaEndOffset + kSystemPointerSize;
@@ -188,7 +183,6 @@ class BasicMemoryChunk {
       + kUIntptrSize            // uintptr_t flags_
       + kSystemPointerSize      // Bitmap* marking_bitmap_
       + kSystemPointerSize      // Heap* heap_
-      + kSystemPointerSize      // Address header_sentinel_
       + kSystemPointerSize      // Address area_start_
       + kSystemPointerSize      // Address area_end_
       + kSystemPointerSize * NUMBER_OF_REMEMBERED_SET_TYPES;  // SlotSet* array
@@ -207,12 +201,6 @@ class BasicMemoryChunk {
   // layout under C++11.
   Heap* heap_;
 
-  // This is used to distinguish the memory chunk header from the interior of a
-  // large page. The memory chunk header stores here an impossible tagged
-  // pointer: the tagger pointer of the page start. A field in a large object is
-  // guaranteed to not contain such a pointer.
-  Address header_sentinel_;
-
   // Start and end of allocatable memory on this chunk.
   Address area_start_;
   Address area_end_;
@@ -237,8 +225,6 @@ class BasicMemoryChunkValidator {
                 offsetof(BasicMemoryChunk, marking_bitmap_));
   STATIC_ASSERT(BasicMemoryChunk::kHeapOffset ==
                 offsetof(BasicMemoryChunk, heap_));
-  STATIC_ASSERT(BasicMemoryChunk::kHeaderSentinelOffset ==
-                offsetof(BasicMemoryChunk, header_sentinel_));
   STATIC_ASSERT(BasicMemoryChunk::kOldToNewSlotSetOffset ==
                 offsetof(BasicMemoryChunk, slot_set_));
 };

src/heap/heap.cc

@@ -6148,8 +6148,6 @@ Code Heap::GcSafeFindCodeForInnerPointer(Address inner_pointer) {
     return GcSafeCastToCode(large_page->GetObject(), inner_pointer);
   }
 
-  DCHECK(code_space()->Contains(inner_pointer));
-
   // Iterate through the page until we reach the end or find an object starting
   // after the inner pointer.
   Page* page = Page::FromAddress(inner_pointer);

src/heap/spaces-inl.h

@@ -160,10 +160,6 @@ bool NewSpace::ToSpaceContainsSlow(Address a) {
 bool NewSpace::ToSpaceContains(Object o) { return to_space_.Contains(o); }
 bool NewSpace::FromSpaceContains(Object o) { return from_space_.Contains(o); }
 
-bool PagedSpace::Contains(Address addr) {
-  return MemoryChunk::FromAnyPointerAddress(addr)->owner() == this;
-}
-
 bool PagedSpace::Contains(Object o) {
   if (!o.IsHeapObject()) return false;
   return Page::FromAddress(o.ptr())->owner() == this;
@@ -201,13 +197,6 @@ bool PagedSpace::TryFreeLast(HeapObject object, int object_size) {
   return false;
 }
 
-MemoryChunk* MemoryChunk::FromAnyPointerAddress(Address addr) {
-  while (!HasHeaderSentinel(addr)) {
-    addr = BaseAddress(addr) - 1;
-  }
-  return FromAddress(addr);
-}
-
 void MemoryChunk::IncrementExternalBackingStoreBytes(
     ExternalBackingStoreType type, size_t amount) {
   base::CheckedIncrement(&external_backing_store_bytes_[type], amount);

src/heap/spaces.cc

@@ -692,7 +692,6 @@ MemoryChunk* MemoryChunk::Initialize(Heap* heap, Address base, size_t size,
   MemoryChunk* chunk = FromAddress(base);
   DCHECK_EQ(base, chunk->address());
   new (chunk) BasicMemoryChunk(size, area_start, area_end);
-  DCHECK(HasHeaderSentinel(area_start));
 
   chunk->heap_ = heap;
   chunk->set_owner(owner);
@@ -803,15 +802,6 @@ LargePage* LargePage::Initialize(Heap* heap, MemoryChunk* chunk,
 
   MSAN_ALLOCATED_UNINITIALIZED_MEMORY(chunk->area_start(), chunk->area_size());
 
-  // Initialize the sentinel value for each page boundary since the mutator
-  // may initialize the object starting from its end.
-  Address sentinel = chunk->address() + MemoryChunk::kHeaderSentinelOffset +
-                     MemoryChunk::kPageSize;
-  while (sentinel < chunk->area_end()) {
-    *reinterpret_cast<intptr_t*>(sentinel) = kNullAddress;
-    sentinel += MemoryChunk::kPageSize;
-  }
-
   LargePage* page = static_cast<LargePage*>(chunk);
   page->SetFlag(MemoryChunk::LARGE_PAGE);
   page->list_node().Initialize();

src/heap/spaces.h

@@ -641,8 +641,6 @@ class MemoryChunk : public BasicMemoryChunk {
   void SetOldGenerationPageFlags(bool is_marking);
   void SetYoungGenerationPageFlags(bool is_marking);
 
-  static inline MemoryChunk* FromAnyPointerAddress(Address addr);
-
   static inline void UpdateHighWaterMark(Address mark) {
     if (mark == kNullAddress) return;
     // Need to subtract one from the mark because when a chunk is full the

test/cctest/heap/test-heap.cc

@@ -6350,7 +6350,7 @@ HEAP_TEST(Regress5831) {
   for (int i = 0; i < kMaxIterations; i++) {
     Handle<Code> code = GenerateDummyImmovableCode(isolate);
     array = FixedArray::SetAndGrow(isolate, array, i, code);
-    CHECK(heap->code_space()->Contains(code->address()) ||
+    CHECK(heap->code_space()->Contains(*code) ||
           heap->code_lo_space()->Contains(*code));
     if (heap->code_lo_space()->Contains(*code)) {
       overflowed_into_lospace = true;

tools/v8heapconst.py

@@ -190,227 +190,227 @@ INSTANCE_TYPES = {
 
 # List of known V8 maps.
 KNOWN_MAPS = {
-  ("read_only_space", 0x00121): (161, "FreeSpaceMap"),
-  ("read_only_space", 0x00171): (162, "MetaMap"),
-  ("read_only_space", 0x001f1): (67, "NullMap"),
-  ("read_only_space", 0x00259): (156, "DescriptorArrayMap"),
-  ("read_only_space", 0x002b9): (151, "WeakFixedArrayMap"),
-  ("read_only_space", 0x00309): (160, "OnePointerFillerMap"),
-  ("read_only_space", 0x00359): (160, "TwoPointerFillerMap"),
-  ("read_only_space", 0x003d9): (67, "UninitializedMap"),
-  ("read_only_space", 0x00449): (8, "OneByteInternalizedStringMap"),
-  ("read_only_space", 0x004e9): (67, "UndefinedMap"),
-  ("read_only_space", 0x00549): (66, "HeapNumberMap"),
-  ("read_only_space", 0x005c9): (67, "TheHoleMap"),
-  ("read_only_space", 0x00671): (67, "BooleanMap"),
-  ("read_only_space", 0x00749): (133, "ByteArrayMap"),
-  ("read_only_space", 0x00799): (118, "FixedArrayMap"),
-  ("read_only_space", 0x007e9): (118, "FixedCOWArrayMap"),
-  ("read_only_space", 0x00839): (119, "HashTableMap"),
-  ("read_only_space", 0x00889): (64, "SymbolMap"),
-  ("read_only_space", 0x008d9): (40, "OneByteStringMap"),
-  ("read_only_space", 0x00929): (131, "ScopeInfoMap"),
-  ("read_only_space", 0x00979): (166, "SharedFunctionInfoMap"),
-  ("read_only_space", 0x009c9): (154, "CodeMap"),
-  ("read_only_space", 0x00a19): (153, "CellMap"),
-  ("read_only_space", 0x00a69): (165, "GlobalPropertyCellMap"),
-  ("read_only_space", 0x00ab9): (70, "ForeignMap"),
-  ("read_only_space", 0x00b09): (152, "TransitionArrayMap"),
-  ("read_only_space", 0x00b59): (45, "ThinOneByteStringMap"),
-  ("read_only_space", 0x00ba9): (159, "FeedbackVectorMap"),
-  ("read_only_space", 0x00c49): (67, "ArgumentsMarkerMap"),
-  ("read_only_space", 0x00ce9): (67, "ExceptionMap"),
-  ("read_only_space", 0x00d89): (67, "TerminationExceptionMap"),
-  ("read_only_space", 0x00e31): (67, "OptimizedOutMap"),
-  ("read_only_space", 0x00ed1): (67, "StaleRegisterMap"),
-  ("read_only_space", 0x00f41): (132, "ScriptContextTableMap"),
-  ("read_only_space", 0x00f91): (129, "ClosureFeedbackCellArrayMap"),
-  ("read_only_space", 0x00fe1): (158, "FeedbackMetadataArrayMap"),
-  ("read_only_space", 0x01031): (118, "ArrayListMap"),
-  ("read_only_space", 0x01081): (65, "BigIntMap"),
-  ("read_only_space", 0x010d1): (130, "ObjectBoilerplateDescriptionMap"),
-  ("read_only_space", 0x01121): (134, "BytecodeArrayMap"),
-  ("read_only_space", 0x01171): (155, "CodeDataContainerMap"),
-  ("read_only_space", 0x011c1): (135, "FixedDoubleArrayMap"),
-  ("read_only_space", 0x01211): (121, "GlobalDictionaryMap"),
-  ("read_only_space", 0x01261): (95, "ManyClosuresCellMap"),
-  ("read_only_space", 0x012b1): (118, "ModuleInfoMap"),
-  ("read_only_space", 0x01301): (122, "NameDictionaryMap"),
-  ("read_only_space", 0x01351): (95, "NoClosuresCellMap"),
-  ("read_only_space", 0x013a1): (123, "NumberDictionaryMap"),
-  ("read_only_space", 0x013f1): (95, "OneClosureCellMap"),
-  ("read_only_space", 0x01441): (124, "OrderedHashMapMap"),
-  ("read_only_space", 0x01491): (125, "OrderedHashSetMap"),
-  ("read_only_space", 0x014e1): (126, "OrderedNameDictionaryMap"),
-  ("read_only_space", 0x01531): (163, "PreparseDataMap"),
-  ("read_only_space", 0x01581): (164, "PropertyArrayMap"),
-  ("read_only_space", 0x015d1): (91, "SideEffectCallHandlerInfoMap"),
-  ("read_only_space", 0x01621): (91, "SideEffectFreeCallHandlerInfoMap"),
-  ("read_only_space", 0x01671): (91, "NextCallSideEffectFreeCallHandlerInfoMap"),
-  ("read_only_space", 0x016c1): (127, "SimpleNumberDictionaryMap"),
-  ("read_only_space", 0x01711): (118, "SloppyArgumentsElementsMap"),
-  ("read_only_space", 0x01761): (146, "SmallOrderedHashMapMap"),
-  ("read_only_space", 0x017b1): (147, "SmallOrderedHashSetMap"),
-  ("read_only_space", 0x01801): (148, "SmallOrderedNameDictionaryMap"),
-  ("read_only_space", 0x01851): (68, "SourceTextModuleMap"),
-  ("read_only_space", 0x018a1): (128, "StringTableMap"),
-  ("read_only_space", 0x018f1): (69, "SyntheticModuleMap"),
-  ("read_only_space", 0x01941): (150, "UncompiledDataWithoutPreparseDataMap"),
-  ("read_only_space", 0x01991): (149, "UncompiledDataWithPreparseDataMap"),
-  ("read_only_space", 0x019e1): (167, "WeakArrayListMap"),
-  ("read_only_space", 0x01a31): (120, "EphemeronHashTableMap"),
-  ("read_only_space", 0x01a81): (157, "EmbedderDataArrayMap"),
-  ("read_only_space", 0x01ad1): (168, "WeakCellMap"),
-  ("read_only_space", 0x01b21): (32, "StringMap"),
-  ("read_only_space", 0x01b71): (41, "ConsOneByteStringMap"),
-  ("read_only_space", 0x01bc1): (33, "ConsStringMap"),
-  ("read_only_space", 0x01c11): (37, "ThinStringMap"),
-  ("read_only_space", 0x01c61): (35, "SlicedStringMap"),
-  ("read_only_space", 0x01cb1): (43, "SlicedOneByteStringMap"),
-  ("read_only_space", 0x01d01): (34, "ExternalStringMap"),
-  ("read_only_space", 0x01d51): (42, "ExternalOneByteStringMap"),
-  ("read_only_space", 0x01da1): (50, "UncachedExternalStringMap"),
-  ("read_only_space", 0x01df1): (0, "InternalizedStringMap"),
-  ("read_only_space", 0x01e41): (2, "ExternalInternalizedStringMap"),
-  ("read_only_space", 0x01e91): (10, "ExternalOneByteInternalizedStringMap"),
-  ("read_only_space", 0x01ee1): (18, "UncachedExternalInternalizedStringMap"),
-  ("read_only_space", 0x01f31): (26, "UncachedExternalOneByteInternalizedStringMap"),
-  ("read_only_space", 0x01f81): (58, "UncachedExternalOneByteStringMap"),
-  ("read_only_space", 0x01fd1): (67, "SelfReferenceMarkerMap"),
-  ("read_only_space", 0x02039): (94, "EnumCacheMap"),
-  ("read_only_space", 0x020d9): (88, "ArrayBoilerplateDescriptionMap"),
-  ("read_only_space", 0x022c9): (97, "InterceptorInfoMap"),
-  ("read_only_space", 0x04c09): (71, "PromiseFulfillReactionJobTaskMap"),
-  ("read_only_space", 0x04c59): (72, "PromiseRejectReactionJobTaskMap"),
-  ("read_only_space", 0x04ca9): (73, "CallableTaskMap"),
-  ("read_only_space", 0x04cf9): (74, "CallbackTaskMap"),
-  ("read_only_space", 0x04d49): (75, "PromiseResolveThenableJobTaskMap"),
-  ("read_only_space", 0x04d99): (78, "FunctionTemplateInfoMap"),
-  ("read_only_space", 0x04de9): (79, "ObjectTemplateInfoMap"),
-  ("read_only_space", 0x04e39): (80, "Tuple2Map"),
-  ("read_only_space", 0x04e89): (81, "Tuple3Map"),
-  ("read_only_space", 0x04ed9): (82, "AccessCheckInfoMap"),
-  ("read_only_space", 0x04f29): (83, "AccessorInfoMap"),
-  ("read_only_space", 0x04f79): (84, "AccessorPairMap"),
-  ("read_only_space", 0x04fc9): (85, "AliasedArgumentsEntryMap"),
-  ("read_only_space", 0x05019): (86, "AllocationMementoMap"),
-  ("read_only_space", 0x05069): (89, "AsmWasmDataMap"),
-  ("read_only_space", 0x050b9): (90, "AsyncGeneratorRequestMap"),
-  ("read_only_space", 0x05109): (92, "ClassPositionsMap"),
-  ("read_only_space", 0x05159): (93, "DebugInfoMap"),
-  ("read_only_space", 0x051a9): (96, "FunctionTemplateRareDataMap"),
-  ("read_only_space", 0x051f9): (99, "InterpreterDataMap"),
-  ("read_only_space", 0x05249): (100, "PromiseCapabilityMap"),
-  ("read_only_space", 0x05299): (101, "PromiseReactionMap"),
-  ("read_only_space", 0x052e9): (102, "PrototypeInfoMap"),
-  ("read_only_space", 0x05339): (103, "ScriptMap"),
-  ("read_only_space", 0x05389): (107, "SourcePositionTableWithFrameCacheMap"),
-  ("read_only_space", 0x053d9): (108, "SourceTextModuleInfoEntryMap"),
-  ("read_only_space", 0x05429): (109, "StackFrameInfoMap"),
-  ("read_only_space", 0x05479): (110, "StackTraceFrameMap"),
-  ("read_only_space", 0x054c9): (111, "TemplateObjectDescriptionMap"),
-  ("read_only_space", 0x05519): (112, "WasmCapiFunctionDataMap"),
-  ("read_only_space", 0x05569): (113, "WasmDebugInfoMap"),
-  ("read_only_space", 0x055b9): (114, "WasmExceptionTagMap"),
-  ("read_only_space", 0x05609): (115, "WasmExportedFunctionDataMap"),
-  ("read_only_space", 0x05659): (116, "WasmIndirectFunctionTableMap"),
-  ("read_only_space", 0x056a9): (117, "WasmJSFunctionDataMap"),
-  ("read_only_space", 0x056f9): (98, "InternalClassMap"),
-  ("read_only_space", 0x05749): (105, "SmiPairMap"),
-  ("read_only_space", 0x05799): (104, "SmiBoxMap"),
-  ("read_only_space", 0x057e9): (106, "SortStateMap"),
-  ("read_only_space", 0x05839): (87, "AllocationSiteWithWeakNextMap"),
-  ("read_only_space", 0x05889): (87, "AllocationSiteWithoutWeakNextMap"),
-  ("read_only_space", 0x058d9): (76, "LoadHandler1Map"),
-  ("read_only_space", 0x05929): (76, "LoadHandler2Map"),
-  ("read_only_space", 0x05979): (76, "LoadHandler3Map"),
-  ("read_only_space", 0x059c9): (77, "StoreHandler0Map"),
-  ("read_only_space", 0x05a19): (77, "StoreHandler1Map"),
-  ("read_only_space", 0x05a69): (77, "StoreHandler2Map"),
-  ("read_only_space", 0x05ab9): (77, "StoreHandler3Map"),
-  ("map_space", 0x00121): (1057, "ExternalMap"),
-  ("map_space", 0x00171): (1072, "JSMessageObjectMap"),
+  ("read_only_space", 0x00119): (161, "FreeSpaceMap"),
+  ("read_only_space", 0x00169): (162, "MetaMap"),
+  ("read_only_space", 0x001e9): (67, "NullMap"),
+  ("read_only_space", 0x00251): (156, "DescriptorArrayMap"),
+  ("read_only_space", 0x002b1): (151, "WeakFixedArrayMap"),
+  ("read_only_space", 0x00301): (160, "OnePointerFillerMap"),
+  ("read_only_space", 0x00351): (160, "TwoPointerFillerMap"),
+  ("read_only_space", 0x003d1): (67, "UninitializedMap"),
+  ("read_only_space", 0x00441): (8, "OneByteInternalizedStringMap"),
+  ("read_only_space", 0x004e1): (67, "UndefinedMap"),
+  ("read_only_space", 0x00541): (66, "HeapNumberMap"),
+  ("read_only_space", 0x005c1): (67, "TheHoleMap"),
+  ("read_only_space", 0x00669): (67, "BooleanMap"),
+  ("read_only_space", 0x00741): (133, "ByteArrayMap"),
+  ("read_only_space", 0x00791): (118, "FixedArrayMap"),
+  ("read_only_space", 0x007e1): (118, "FixedCOWArrayMap"),
+  ("read_only_space", 0x00831): (119, "HashTableMap"),
+  ("read_only_space", 0x00881): (64, "SymbolMap"),
+  ("read_only_space", 0x008d1): (40, "OneByteStringMap"),
+  ("read_only_space", 0x00921): (131, "ScopeInfoMap"),
+  ("read_only_space", 0x00971): (166, "SharedFunctionInfoMap"),
+  ("read_only_space", 0x009c1): (154, "CodeMap"),
+  ("read_only_space", 0x00a11): (153, "CellMap"),
+  ("read_only_space", 0x00a61): (165, "GlobalPropertyCellMap"),
+  ("read_only_space", 0x00ab1): (70, "ForeignMap"),
+  ("read_only_space", 0x00b01): (152, "TransitionArrayMap"),
+  ("read_only_space", 0x00b51): (45, "ThinOneByteStringMap"),
+  ("read_only_space", 0x00ba1): (159, "FeedbackVectorMap"),
+  ("read_only_space", 0x00c41): (67, "ArgumentsMarkerMap"),
+  ("read_only_space", 0x00ce1): (67, "ExceptionMap"),
+  ("read_only_space", 0x00d81): (67, "TerminationExceptionMap"),
+  ("read_only_space", 0x00e29): (67, "OptimizedOutMap"),
+  ("read_only_space", 0x00ec9): (67, "StaleRegisterMap"),
+  ("read_only_space", 0x00f39): (132, "ScriptContextTableMap"),
+  ("read_only_space", 0x00f89): (129, "ClosureFeedbackCellArrayMap"),
+  ("read_only_space", 0x00fd9): (158, "FeedbackMetadataArrayMap"),
+  ("read_only_space", 0x01029): (118, "ArrayListMap"),
+  ("read_only_space", 0x01079): (65, "BigIntMap"),
+  ("read_only_space", 0x010c9): (130, "ObjectBoilerplateDescriptionMap"),
+  ("read_only_space", 0x01119): (134, "BytecodeArrayMap"),
+  ("read_only_space", 0x01169): (155, "CodeDataContainerMap"),
+  ("read_only_space", 0x011b9): (135, "FixedDoubleArrayMap"),
+  ("read_only_space", 0x01209): (121, "GlobalDictionaryMap"),
+  ("read_only_space", 0x01259): (95, "ManyClosuresCellMap"),
+  ("read_only_space", 0x012a9): (118, "ModuleInfoMap"),
+  ("read_only_space", 0x012f9): (122, "NameDictionaryMap"),
+  ("read_only_space", 0x01349): (95, "NoClosuresCellMap"),
+  ("read_only_space", 0x01399): (123, "NumberDictionaryMap"),
+  ("read_only_space", 0x013e9): (95, "OneClosureCellMap"),
+  ("read_only_space", 0x01439): (124, "OrderedHashMapMap"),
+  ("read_only_space", 0x01489): (125, "OrderedHashSetMap"),
+  ("read_only_space", 0x014d9): (126, "OrderedNameDictionaryMap"),
+  ("read_only_space", 0x01529): (163, "PreparseDataMap"),
+  ("read_only_space", 0x01579): (164, "PropertyArrayMap"),
+  ("read_only_space", 0x015c9): (91, "SideEffectCallHandlerInfoMap"),
+  ("read_only_space", 0x01619): (91, "SideEffectFreeCallHandlerInfoMap"),
+  ("read_only_space", 0x01669): (91, "NextCallSideEffectFreeCallHandlerInfoMap"),
+  ("read_only_space", 0x016b9): (127, "SimpleNumberDictionaryMap"),
+  ("read_only_space", 0x01709): (118, "SloppyArgumentsElementsMap"),
+  ("read_only_space", 0x01759): (146, "SmallOrderedHashMapMap"),
+  ("read_only_space", 0x017a9): (147, "SmallOrderedHashSetMap"),
+  ("read_only_space", 0x017f9): (148, "SmallOrderedNameDictionaryMap"),
+  ("read_only_space", 0x01849): (68, "SourceTextModuleMap"),
+  ("read_only_space", 0x01899): (128, "StringTableMap"),
+  ("read_only_space", 0x018e9): (69, "SyntheticModuleMap"),
+  ("read_only_space", 0x01939): (150, "UncompiledDataWithoutPreparseDataMap"),
+  ("read_only_space", 0x01989): (149, "UncompiledDataWithPreparseDataMap"),
+  ("read_only_space", 0x019d9): (167, "WeakArrayListMap"),
+  ("read_only_space", 0x01a29): (120, "EphemeronHashTableMap"),
+  ("read_only_space", 0x01a79): (157, "EmbedderDataArrayMap"),
+  ("read_only_space", 0x01ac9): (168, "WeakCellMap"),
+  ("read_only_space", 0x01b19): (32, "StringMap"),
+  ("read_only_space", 0x01b69): (41, "ConsOneByteStringMap"),
+  ("read_only_space", 0x01bb9): (33, "ConsStringMap"),
+  ("read_only_space", 0x01c09): (37, "ThinStringMap"),
+  ("read_only_space", 0x01c59): (35, "SlicedStringMap"),
+  ("read_only_space", 0x01ca9): (43, "SlicedOneByteStringMap"),
+  ("read_only_space", 0x01cf9): (34, "ExternalStringMap"),
+  ("read_only_space", 0x01d49): (42, "ExternalOneByteStringMap"),
+  ("read_only_space", 0x01d99): (50, "UncachedExternalStringMap"),
+  ("read_only_space", 0x01de9): (0, "InternalizedStringMap"),
+  ("read_only_space", 0x01e39): (2, "ExternalInternalizedStringMap"),
+  ("read_only_space", 0x01e89): (10, "ExternalOneByteInternalizedStringMap"),
+  ("read_only_space", 0x01ed9): (18, "UncachedExternalInternalizedStringMap"),
+  ("read_only_space", 0x01f29): (26, "UncachedExternalOneByteInternalizedStringMap"),
+  ("read_only_space", 0x01f79): (58, "UncachedExternalOneByteStringMap"),
+  ("read_only_space", 0x01fc9): (67, "SelfReferenceMarkerMap"),
+  ("read_only_space", 0x02031): (94, "EnumCacheMap"),
+  ("read_only_space", 0x020d1): (88, "ArrayBoilerplateDescriptionMap"),
+  ("read_only_space", 0x022c1): (97, "InterceptorInfoMap"),
+  ("read_only_space", 0x04c01): (71, "PromiseFulfillReactionJobTaskMap"),
+  ("read_only_space", 0x04c51): (72, "PromiseRejectReactionJobTaskMap"),
+  ("read_only_space", 0x04ca1): (73, "CallableTaskMap"),
+  ("read_only_space", 0x04cf1): (74, "CallbackTaskMap"),
+  ("read_only_space", 0x04d41): (75, "PromiseResolveThenableJobTaskMap"),
+  ("read_only_space", 0x04d91): (78, "FunctionTemplateInfoMap"),
+  ("read_only_space", 0x04de1): (79, "ObjectTemplateInfoMap"),
+  ("read_only_space", 0x04e31): (80, "Tuple2Map"),
+  ("read_only_space", 0x04e81): (81, "Tuple3Map"),
+  ("read_only_space", 0x04ed1): (82, "AccessCheckInfoMap"),
+  ("read_only_space", 0x04f21): (83, "AccessorInfoMap"),
+  ("read_only_space", 0x04f71): (84, "AccessorPairMap"),
+  ("read_only_space", 0x04fc1): (85, "AliasedArgumentsEntryMap"),
+  ("read_only_space", 0x05011): (86, "AllocationMementoMap"),
+  ("read_only_space", 0x05061): (89, "AsmWasmDataMap"),
+  ("read_only_space", 0x050b1): (90, "AsyncGeneratorRequestMap"),
+  ("read_only_space", 0x05101): (92, "ClassPositionsMap"),
+  ("read_only_space", 0x05151): (93, "DebugInfoMap"),
+  ("read_only_space", 0x051a1): (96, "FunctionTemplateRareDataMap"),
+  ("read_only_space", 0x051f1): (99, "InterpreterDataMap"),
+  ("read_only_space", 0x05241): (100, "PromiseCapabilityMap"),
+  ("read_only_space", 0x05291): (101, "PromiseReactionMap"),
+  ("read_only_space", 0x052e1): (102, "PrototypeInfoMap"),
+  ("read_only_space", 0x05331): (103, "ScriptMap"),
+  ("read_only_space", 0x05381): (107, "SourcePositionTableWithFrameCacheMap"),
+  ("read_only_space", 0x053d1): (108, "SourceTextModuleInfoEntryMap"),
+  ("read_only_space", 0x05421): (109, "StackFrameInfoMap"),
+  ("read_only_space", 0x05471): (110, "StackTraceFrameMap"),
+  ("read_only_space", 0x054c1): (111, "TemplateObjectDescriptionMap"),
+  ("read_only_space", 0x05511): (112, "WasmCapiFunctionDataMap"),
+  ("read_only_space", 0x05561): (113, "WasmDebugInfoMap"),
+  ("read_only_space", 0x055b1): (114, "WasmExceptionTagMap"),
+  ("read_only_space", 0x05601): (115, "WasmExportedFunctionDataMap"),
+  ("read_only_space", 0x05651): (116, "WasmIndirectFunctionTableMap"),
+  ("read_only_space", 0x056a1): (117, "WasmJSFunctionDataMap"),
+  ("read_only_space", 0x056f1): (98, "InternalClassMap"),
+  ("read_only_space", 0x05741): (105, "SmiPairMap"),
+  ("read_only_space", 0x05791): (104, "SmiBoxMap"),
+  ("read_only_space", 0x057e1): (106, "SortStateMap"),
+  ("read_only_space", 0x05831): (87, "AllocationSiteWithWeakNextMap"),
+  ("read_only_space", 0x05881): (87, "AllocationSiteWithoutWeakNextMap"),
+  ("read_only_space", 0x058d1): (76, "LoadHandler1Map"),
+  ("read_only_space", 0x05921): (76, "LoadHandler2Map"),
+  ("read_only_space", 0x05971): (76, "LoadHandler3Map"),
+  ("read_only_space", 0x059c1): (77, "StoreHandler0Map"),
+  ("read_only_space", 0x05a11): (77, "StoreHandler1Map"),
+  ("read_only_space", 0x05a61): (77, "StoreHandler2Map"),
+  ("read_only_space", 0x05ab1): (77, "StoreHandler3Map"),
+  ("map_space", 0x00119): (1057, "ExternalMap"),
+  ("map_space", 0x00169): (1072, "JSMessageObjectMap"),
 }
 
 # List of known V8 objects.
 KNOWN_OBJECTS = {
-  ("read_only_space", 0x001c1): "NullValue",
-  ("read_only_space", 0x00241): "EmptyDescriptorArray",
-  ("read_only_space", 0x002a9): "EmptyWeakFixedArray",
-  ("read_only_space", 0x003a9): "UninitializedValue",
-  ("read_only_space", 0x004b9): "UndefinedValue",
-  ("read_only_space", 0x00539): "NanValue",
-  ("read_only_space", 0x00599): "TheHoleValue",
-  ("read_only_space", 0x00631): "HoleNanValue",
-  ("read_only_space", 0x00641): "TrueValue",
-  ("read_only_space", 0x006f1): "FalseValue",
-  ("read_only_space", 0x00739): "empty_string",
-  ("read_only_space", 0x00bf9): "EmptyScopeInfo",
-  ("read_only_space", 0x00c09): "EmptyFixedArray",
-  ("read_only_space", 0x00c19): "ArgumentsMarker",
-  ("read_only_space", 0x00cb9): "Exception",
-  ("read_only_space", 0x00d59): "TerminationException",
-  ("read_only_space", 0x00e01): "OptimizedOut",
-  ("read_only_space", 0x00ea1): "StaleRegister",
-  ("read_only_space", 0x02021): "EmptyEnumCache",
-  ("read_only_space", 0x02089): "EmptyPropertyArray",
-  ("read_only_space", 0x02099): "EmptyByteArray",
-  ("read_only_space", 0x020a9): "EmptyObjectBoilerplateDescription",
-  ("read_only_space", 0x020c1): "EmptyArrayBoilerplateDescription",
-  ("read_only_space", 0x02129): "EmptyClosureFeedbackCellArray",
-  ("read_only_space", 0x02139): "EmptySloppyArgumentsElements",
-  ("read_only_space", 0x02159): "EmptySlowElementDictionary",
-  ("read_only_space", 0x021a1): "EmptyOrderedHashMap",
-  ("read_only_space", 0x021c9): "EmptyOrderedHashSet",
-  ("read_only_space", 0x021f1): "EmptyFeedbackMetadata",
-  ("read_only_space", 0x02201): "EmptyPropertyCell",
-  ("read_only_space", 0x02229): "EmptyPropertyDictionary",
-  ("read_only_space", 0x02279): "NoOpInterceptorInfo",
-  ("read_only_space", 0x02319): "EmptyWeakArrayList",
-  ("read_only_space", 0x02331): "InfinityValue",
-  ("read_only_space", 0x02341): "MinusZeroValue",
-  ("read_only_space", 0x02351): "MinusInfinityValue",
-  ("read_only_space", 0x02361): "SelfReferenceMarker",
-  ("read_only_space", 0x023b9): "OffHeapTrampolineRelocationInfo",
-  ("read_only_space", 0x023d1): "TrampolineTrivialCodeDataContainer",
-  ("read_only_space", 0x023e9): "TrampolinePromiseRejectionCodeDataContainer",
-  ("read_only_space", 0x02401): "GlobalThisBindingScopeInfo",
-  ("read_only_space", 0x02469): "EmptyFunctionScopeInfo",
-  ("read_only_space", 0x024b9): "HashSeed",
-  ("old_space", 0x00121): "ArgumentsIteratorAccessor",
-  ("old_space", 0x00191): "ArrayLengthAccessor",
-  ("old_space", 0x00201): "BoundFunctionLengthAccessor",
-  ("old_space", 0x00271): "BoundFunctionNameAccessor",
-  ("old_space", 0x002e1): "ErrorStackAccessor",
-  ("old_space", 0x00351): "FunctionArgumentsAccessor",
-  ("old_space", 0x003c1): "FunctionCallerAccessor",
-  ("old_space", 0x00431): "FunctionNameAccessor",
-  ("old_space", 0x004a1): "FunctionLengthAccessor",
-  ("old_space", 0x00511): "FunctionPrototypeAccessor",
-  ("old_space", 0x00581): "RegExpResultIndicesAccessor",
-  ("old_space", 0x005f1): "StringLengthAccessor",
-  ("old_space", 0x00661): "InvalidPrototypeValidityCell",
-  ("old_space", 0x00671): "EmptyScript",
-  ("old_space", 0x006f1): "ManyClosuresCell",
-  ("old_space", 0x00709): "ArrayConstructorProtector",
-  ("old_space", 0x00731): "NoElementsProtector",
-  ("old_space", 0x00759): "IsConcatSpreadableProtector",
-  ("old_space", 0x00781): "ArraySpeciesProtector",
-  ("old_space", 0x007a9): "TypedArraySpeciesProtector",
-  ("old_space", 0x007d1): "PromiseSpeciesProtector",
-  ("old_space", 0x007f9): "StringLengthProtector",
-  ("old_space", 0x00821): "ArrayIteratorProtector",
-  ("old_space", 0x00849): "ArrayBufferDetachingProtector",
-  ("old_space", 0x00871): "PromiseHookProtector",
-  ("old_space", 0x00899): "PromiseResolveProtector",
-  ("old_space", 0x008c1): "MapIteratorProtector",
-  ("old_space", 0x008e9): "PromiseThenProtector",
-  ("old_space", 0x00911): "SetIteratorProtector",
-  ("old_space", 0x00939): "StringIteratorProtector",
-  ("old_space", 0x00961): "SingleCharacterStringCache",
-  ("old_space", 0x01171): "StringSplitCache",
-  ("old_space", 0x01981): "RegExpMultipleCache",
-  ("old_space", 0x02191): "BuiltinsConstantsTable",
+  ("read_only_space", 0x001b9): "NullValue",
+  ("read_only_space", 0x00239): "EmptyDescriptorArray",
+  ("read_only_space", 0x002a1): "EmptyWeakFixedArray",
+  ("read_only_space", 0x003a1): "UninitializedValue",
+  ("read_only_space", 0x004b1): "UndefinedValue",
+  ("read_only_space", 0x00531): "NanValue",
+  ("read_only_space", 0x00591): "TheHoleValue",
+  ("read_only_space", 0x00629): "HoleNanValue",
+  ("read_only_space", 0x00639): "TrueValue",
+  ("read_only_space", 0x006e9): "FalseValue",
+  ("read_only_space", 0x00731): "empty_string",
+  ("read_only_space", 0x00bf1): "EmptyScopeInfo",
+  ("read_only_space", 0x00c01): "EmptyFixedArray",
+  ("read_only_space", 0x00c11): "ArgumentsMarker",
+  ("read_only_space", 0x00cb1): "Exception",
+  ("read_only_space", 0x00d51): "TerminationException",
+  ("read_only_space", 0x00df9): "OptimizedOut",
+  ("read_only_space", 0x00e99): "StaleRegister",
+  ("read_only_space", 0x02019): "EmptyEnumCache",
+  ("read_only_space", 0x02081): "EmptyPropertyArray",
+  ("read_only_space", 0x02091): "EmptyByteArray",
+  ("read_only_space", 0x020a1): "EmptyObjectBoilerplateDescription",
+  ("read_only_space", 0x020b9): "EmptyArrayBoilerplateDescription",
+  ("read_only_space", 0x02121): "EmptyClosureFeedbackCellArray",
+  ("read_only_space", 0x02131): "EmptySloppyArgumentsElements",
+  ("read_only_space", 0x02151): "EmptySlowElementDictionary",
+  ("read_only_space", 0x02199): "EmptyOrderedHashMap",
+  ("read_only_space", 0x021c1): "EmptyOrderedHashSet",
+  ("read_only_space", 0x021e9): "EmptyFeedbackMetadata",
+  ("read_only_space", 0x021f9): "EmptyPropertyCell",
+  ("read_only_space", 0x02221): "EmptyPropertyDictionary",
+  ("read_only_space", 0x02271): "NoOpInterceptorInfo",
+  ("read_only_space", 0x02311): "EmptyWeakArrayList",
+  ("read_only_space", 0x02329): "InfinityValue",
+  ("read_only_space", 0x02339): "MinusZeroValue",
+  ("read_only_space", 0x02349): "MinusInfinityValue",
+  ("read_only_space", 0x02359): "SelfReferenceMarker",
+  ("read_only_space", 0x023b1): "OffHeapTrampolineRelocationInfo",
+  ("read_only_space", 0x023c9): "TrampolineTrivialCodeDataContainer",
+  ("read_only_space", 0x023e1): "TrampolinePromiseRejectionCodeDataContainer",
+  ("read_only_space", 0x023f9): "GlobalThisBindingScopeInfo",
+  ("read_only_space", 0x02461): "EmptyFunctionScopeInfo",
+  ("read_only_space", 0x024b1): "HashSeed",
+  ("old_space", 0x00119): "ArgumentsIteratorAccessor",
+  ("old_space", 0x00189): "ArrayLengthAccessor",
+  ("old_space", 0x001f9): "BoundFunctionLengthAccessor",
+  ("old_space", 0x00269): "BoundFunctionNameAccessor",
+  ("old_space", 0x002d9): "ErrorStackAccessor",
+  ("old_space", 0x00349): "FunctionArgumentsAccessor",
+  ("old_space", 0x003b9): "FunctionCallerAccessor",
+  ("old_space", 0x00429): "FunctionNameAccessor",
+  ("old_space", 0x00499): "FunctionLengthAccessor",
+  ("old_space", 0x00509): "FunctionPrototypeAccessor",
+  ("old_space", 0x00579): "RegExpResultIndicesAccessor",
+  ("old_space", 0x005e9): "StringLengthAccessor",
+  ("old_space", 0x00659): "InvalidPrototypeValidityCell",
+  ("old_space", 0x00669): "EmptyScript",
+  ("old_space", 0x006e9): "ManyClosuresCell",
+  ("old_space", 0x00701): "ArrayConstructorProtector",
+  ("old_space", 0x00729): "NoElementsProtector",
+  ("old_space", 0x00751): "IsConcatSpreadableProtector",
+  ("old_space", 0x00779): "ArraySpeciesProtector",
+  ("old_space", 0x007a1): "TypedArraySpeciesProtector",
+  ("old_space", 0x007c9): "PromiseSpeciesProtector",
+  ("old_space", 0x007f1): "StringLengthProtector",
+  ("old_space", 0x00819): "ArrayIteratorProtector",
+  ("old_space", 0x00841): "ArrayBufferDetachingProtector",
+  ("old_space", 0x00869): "PromiseHookProtector",
+  ("old_space", 0x00891): "PromiseResolveProtector",
+  ("old_space", 0x008b9): "MapIteratorProtector",
+  ("old_space", 0x008e1): "PromiseThenProtector",
+  ("old_space", 0x00909): "SetIteratorProtector",
+  ("old_space", 0x00931): "StringIteratorProtector",
+  ("old_space", 0x00959): "SingleCharacterStringCache",
+  ("old_space", 0x01169): "StringSplitCache",
+  ("old_space", 0x01979): "RegExpMultipleCache",
+  ("old_space", 0x02189): "BuiltinsConstantsTable",
 }
 
 # List of known V8 Frame Markers.