Revert "[compiler] Replace ScopeInfoData with direct reads"

This reverts commit 7b9a0c20f3. Reason for revert: Different tests start flaking, e.g. https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20gc%20stress/29532 Original change's description: > [compiler] Replace ScopeInfoData with direct reads > > As part of this, introduce a new ObjectData kind for objects that we > want to read directly from the background thread rather than serialize. > ScopeInfoRef is the first user of that. > > For details, see: > https://docs.google.com/document/d/1U6x6Q2bpylfxS55nxSe17yyBW0bQG-ycoBhVA82VmS0/edit?usp=sharing > > Bug: v8:7790 > Change-Id: Ia3cda4f67d3922367afa4a5da2aeaae7160cf1f2 > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2346405 > Auto-Submit: Georg Neis <neis@chromium.org> > Commit-Queue: Georg Neis <neis@chromium.org> > Reviewed-by: Nico Hartmann <nicohartmann@chromium.org> > Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org> > Cr-Commit-Position: refs/heads/master@{#69473} TBR=neis@chromium.org,solanes@chromium.org,nicohartmann@chromium.org Change-Id: Ide5a4a583547b63cc9accfb93fcadb97b8100e8a No-Presubmit: true No-Tree-Checks: true No-Try: true Bug: v8:7790 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2364504 Reviewed-by: Clemens Backes <clemensb@chromium.org> Commit-Queue: Clemens Backes <clemensb@chromium.org> Cr-Commit-Position: refs/heads/master@{#69487}
2020-08-19 16:17:57 +00:00 · 2020-08-19 16:17:57 +00:00 · 536092f779
commit 536092f779
parent 45f296f7f9
10 changed files with 189 additions and 167 deletions
--- a/src/ast/scopes.h
+++ b/src/ast/scopes.h
@ -705,6 +705,8 @@ class V8_EXPORT_PRIVATE Scope : public NON_EXPORTED_BASE(ZoneObject) {

  void SetDefaults();

+  void set_scope_info(Handle<ScopeInfo> scope_info);
+
  friend class DeclarationScope;
  friend class ClassScope;
  friend class ScopeTestHelper;
--- a/src/codegen/compiler.cc
+++ b/src/codegen/compiler.cc
@ -596,7 +596,7 @@ void UpdateSharedFunctionFlagsAfterCompilation(FunctionLiteral* literal,
  shared_info.set_has_static_private_methods_or_accessors(
      literal->has_static_private_methods_or_accessors());

-  shared_info.SetScopeInfo(*literal->scope()->scope_info());
+  shared_info.set_scope_info(*literal->scope()->scope_info());
 }

 // Finalize a single compilation job. This function can return
--- a/src/compiler/bytecode-graph-builder.cc
+++ b/src/compiler/bytecode-graph-builder.cc
@ -1785,7 +1785,7 @@ BytecodeGraphBuilder::Environment* BytecodeGraphBuilder::CheckContextExtensions(
  // in the same scope as the variable itself has no way of shadowing it.
  Environment* slow_environment = nullptr;
  for (uint32_t d = 0; d < depth; d++) {
-    if (scope_info.HasContextExtensionSlot()) {
+    if (scope_info.HasContextExtension()) {
      slow_environment = CheckContextExtensionAtDepth(slow_environment, d);
    }
    DCHECK_IMPLIES(!scope_info.HasOuterScopeInfo(), d + 1 == depth);
--- a/src/compiler/heap-refs.h
+++ b/src/compiler/heap-refs.h
@ -49,7 +49,7 @@ enum class OddballType : uint8_t {

 // This list is sorted such that subtypes appear before their supertypes.
 // DO NOT VIOLATE THIS PROPERTY!
-#define HEAP_BROKER_SERIALIZED_OBJECT_LIST(V) \
+#define HEAP_BROKER_OBJECT_LIST(V) \
  /* Subtypes of JSObject */       \
  V(JSArray)                       \
  V(JSBoundFunction)               \
@ -64,6 +64,7 @@ enum class OddballType : uint8_t {
  /* Subtypes of FixedArray */     \
  V(Context)                       \
  V(ObjectBoilerplateDescription)  \
+  V(ScopeInfo)                     \
  V(ScriptContextTable)            \
  /* Subtypes of FixedArrayBase */ \
  V(BytecodeArray)                 \
@ -99,8 +100,6 @@ enum class OddballType : uint8_t {
  /* Subtypes of Object */         \
  V(HeapObject)

-#define HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(V) V(ScopeInfo)
-
 class CompilationDependencies;
 struct FeedbackSource;
 class JSHeapBroker;
@ -108,8 +107,7 @@ class ObjectData;
 class PerIsolateCompilerCache;
 class PropertyAccessInfo;
 #define FORWARD_DECL(Name) class Name##Ref;
-HEAP_BROKER_SERIALIZED_OBJECT_LIST(FORWARD_DECL)
-HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(FORWARD_DECL)
+HEAP_BROKER_OBJECT_LIST(FORWARD_DECL)
 #undef FORWARD_DECL

 class V8_EXPORT_PRIVATE ObjectRef {
@ -129,13 +127,11 @@ class V8_EXPORT_PRIVATE ObjectRef {
  int AsSmi() const;

 #define HEAP_IS_METHOD_DECL(Name) bool Is##Name() const;
-  HEAP_BROKER_SERIALIZED_OBJECT_LIST(HEAP_IS_METHOD_DECL)
-  HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(HEAP_IS_METHOD_DECL)
+  HEAP_BROKER_OBJECT_LIST(HEAP_IS_METHOD_DECL)
 #undef HEAP_IS_METHOD_DECL

 #define HEAP_AS_METHOD_DECL(Name) Name##Ref As##Name() const;
-  HEAP_BROKER_SERIALIZED_OBJECT_LIST(HEAP_AS_METHOD_DECL)
-  HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(HEAP_AS_METHOD_DECL)
+  HEAP_BROKER_OBJECT_LIST(HEAP_AS_METHOD_DECL)
 #undef HEAP_AS_METHOD_DECL

  bool IsNullOrUndefined() const;
@ -764,7 +760,8 @@ class ScopeInfoRef : public HeapObjectRef {

  int ContextLength() const;
  bool HasOuterScopeInfo() const;
-  bool HasContextExtensionSlot() const;
+  int Flags() const;
+  bool HasContextExtension() const;

  // Only serialized via SerializeScopeInfoChain.
  ScopeInfoRef OuterScopeInfo() const;
--- a/src/compiler/js-heap-broker.cc
+++ b/src/compiler/js-heap-broker.cc
@ -45,7 +45,7 @@ namespace compiler {
 #define TRACE_MISSING(broker, x) TRACE_BROKER_MISSING(broker, x)

 #define FORWARD_DECL(Name) class Name##Data;
-HEAP_BROKER_SERIALIZED_OBJECT_LIST(FORWARD_DECL)
+HEAP_BROKER_OBJECT_LIST(FORWARD_DECL)
 #undef FORWARD_DECL

 // There are three kinds of ObjectData values.
@ -71,7 +71,6 @@ enum ObjectDataKind {
  kSmi,
  kSerializedHeapObject,
  kUnserializedHeapObject,
-  kNeverSerializedHeapObject,
  kUnserializedReadOnlyHeapObject
 };

@ -80,8 +79,7 @@ class AllowHandleAllocationIf {
  explicit AllowHandleAllocationIf(ObjectDataKind kind,
                                   JSHeapBroker::BrokerMode mode) {
    DCHECK_IMPLIES(mode == JSHeapBroker::BrokerMode::kSerialized,
-                   kind == kUnserializedReadOnlyHeapObject ||
-                       kind == kNeverSerializedHeapObject);
+                   kind == kUnserializedReadOnlyHeapObject);
    if (kind == kUnserializedHeapObject) maybe_allow_handle_.emplace();
  }

@ -92,15 +90,16 @@ class AllowHandleAllocationIf {
 class AllowHandleDereferenceIf {
 public:
  explicit AllowHandleDereferenceIf(ObjectDataKind kind,
-                                    JSHeapBroker::BrokerMode mode)
-      : AllowHandleDereferenceIf(kind) {
+                                    JSHeapBroker::BrokerMode mode) {
    DCHECK_IMPLIES(mode == JSHeapBroker::BrokerMode::kSerialized,
-                   kind == kUnserializedReadOnlyHeapObject ||
-                       kind == kNeverSerializedHeapObject);
+                   kind == kUnserializedReadOnlyHeapObject);
+    if (kind == kUnserializedHeapObject ||
+        kind == kUnserializedReadOnlyHeapObject)
+      maybe_allow_handle_.emplace();
  }

  explicit AllowHandleDereferenceIf(ObjectDataKind kind) {
-    if (kind == kUnserializedHeapObject || kind == kNeverSerializedHeapObject ||
+    if (kind == kUnserializedHeapObject ||
        kind == kUnserializedReadOnlyHeapObject)
      maybe_allow_handle_.emplace();
  }
@ -155,26 +154,20 @@ class ObjectData : public ZoneObject {
            broker->mode() == JSHeapBroker::kSerializing,
        broker->isolate()->handle_scope_data()->canonical_scope != nullptr);
    CHECK_IMPLIES(broker->mode() == JSHeapBroker::kSerialized,
-                  (kind == kUnserializedReadOnlyHeapObject &&
-                   IsReadOnlyHeapObject(*object)) ||
-                      kind == kNeverSerializedHeapObject);
+                  IsReadOnlyHeapObject(*object));
  }

-#define DECLARE_IS(Name) bool Is##Name() const;
-  HEAP_BROKER_SERIALIZED_OBJECT_LIST(DECLARE_IS)
-  HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(DECLARE_IS)
-#undef DECLARE_IS
-
-#define DECLARE_AS(Name) Name##Data* As##Name();
-  HEAP_BROKER_SERIALIZED_OBJECT_LIST(DECLARE_AS)
-#undef DECLARE_AS
+#define DECLARE_IS_AND_AS(Name) \
+  bool Is##Name() const;        \
+  Name##Data* As##Name();
+  HEAP_BROKER_OBJECT_LIST(DECLARE_IS_AND_AS)
+#undef DECLARE_IS_AND_AS

  Handle<Object> object() const { return object_; }
  ObjectDataKind kind() const { return kind_; }
  bool is_smi() const { return kind_ == kSmi; }
  bool should_access_heap() const {
    return kind_ == kUnserializedHeapObject ||
-           kind_ == kNeverSerializedHeapObject ||
           kind_ == kUnserializedReadOnlyHeapObject;
  }

@ -779,7 +772,7 @@ class NativeContextData : public ContextData {
    return function_maps_;
  }

-  ObjectData* scope_info() const {
+  ScopeInfoData* scope_info() const {
    CHECK(serialized_);
    return scope_info_;
  }
@ -794,7 +787,7 @@ class NativeContextData : public ContextData {
  BROKER_NATIVE_CONTEXT_FIELDS(DECL_MEMBER)
 #undef DECL_MEMBER
  ZoneVector<MapData*> function_maps_;
-  ObjectData* scope_info_ = nullptr;
+  ScopeInfoData* scope_info_ = nullptr;
 };

 class NameData : public HeapObjectData {
@ -1669,6 +1662,45 @@ ObjectData* JSArrayData::GetOwnElement(JSHeapBroker* broker, uint32_t index,
  return result;
 }

+class ScopeInfoData : public HeapObjectData {
+ public:
+  ScopeInfoData(JSHeapBroker* broker, ObjectData** storage,
+                Handle<ScopeInfo> object);
+
+  int context_length() const { return context_length_; }
+  bool has_outer_scope_info() const { return has_outer_scope_info_; }
+  int flags() const { return flags_; }
+
+  ScopeInfoData* outer_scope_info() const { return outer_scope_info_; }
+  void SerializeScopeInfoChain(JSHeapBroker* broker);
+
+ private:
+  int const context_length_;
+  bool const has_outer_scope_info_;
+  int const flags_;
+
+  // Only serialized via SerializeScopeInfoChain.
+  ScopeInfoData* outer_scope_info_;
+};
+
+ScopeInfoData::ScopeInfoData(JSHeapBroker* broker, ObjectData** storage,
+                             Handle<ScopeInfo> object)
+    : HeapObjectData(broker, storage, object),
+      context_length_(object->ContextLength()),
+      has_outer_scope_info_(object->HasOuterScopeInfo()),
+      flags_(object->Flags()),
+      outer_scope_info_(nullptr) {}
+
+void ScopeInfoData::SerializeScopeInfoChain(JSHeapBroker* broker) {
+  if (outer_scope_info_) return;
+  if (!has_outer_scope_info_) return;
+  outer_scope_info_ =
+      broker
+          ->GetOrCreateData(Handle<ScopeInfo>::cast(object())->OuterScopeInfo())
+          ->AsScopeInfo();
+  outer_scope_info_->SerializeScopeInfoChain(broker);
+}
+
 class SharedFunctionInfoData : public HeapObjectData {
 public:
  SharedFunctionInfoData(JSHeapBroker* broker, ObjectData** storage,
@ -1678,7 +1710,7 @@ class SharedFunctionInfoData : public HeapObjectData {
  int context_header_size() const { return context_header_size_; }
  BytecodeArrayData* GetBytecodeArray() const { return GetBytecodeArray_; }
  void SerializeFunctionTemplateInfo(JSHeapBroker* broker);
-  ObjectData* scope_info() const { return scope_info_; }
+  ScopeInfoData* scope_info() const { return scope_info_; }
  void SerializeScopeInfoChain(JSHeapBroker* broker);
  FunctionTemplateInfoData* function_template_info() const {
    return function_template_info_;
@ -1709,7 +1741,7 @@ class SharedFunctionInfoData : public HeapObjectData {
 #undef DECL_MEMBER
  FunctionTemplateInfoData* function_template_info_;
  ZoneMap<int, JSArrayData*> template_objects_;
-  ObjectData* scope_info_;
+  ScopeInfoData* scope_info_;
 };

 SharedFunctionInfoData::SharedFunctionInfoData(
@ -1749,8 +1781,12 @@ void SharedFunctionInfoData::SerializeFunctionTemplateInfo(

 void SharedFunctionInfoData::SerializeScopeInfoChain(JSHeapBroker* broker) {
  if (scope_info_) return;
-  scope_info_ = broker->GetOrCreateData(
-      Handle<SharedFunctionInfo>::cast(object())->synchronized_scope_info());
+  scope_info_ =
+      broker
+          ->GetOrCreateData(
+              Handle<SharedFunctionInfo>::cast(object())->scope_info())
+          ->AsScopeInfo();
+  scope_info_->SerializeScopeInfoChain(broker);
 }

 class SourceTextModuleData : public HeapObjectData {
@ -1957,7 +1993,7 @@ class CodeData : public HeapObjectData {
  unsigned const inlined_bytecode_size_;
 };

-#define DEFINE_IS(Name)                                                 \
+#define DEFINE_IS_AND_AS(Name)                                          \
  bool ObjectData::Is##Name() const {                                   \
    if (should_access_heap()) {                                         \
      AllowHandleDereferenceIf allow_handle_dereference(kind());        \
@ -1967,18 +2003,13 @@ class CodeData : public HeapObjectData {
    InstanceType instance_type =                                        \
        static_cast<const HeapObjectData*>(this)->GetMapInstanceType(); \
    return InstanceTypeChecker::Is##Name(instance_type);                \
-  }
-HEAP_BROKER_SERIALIZED_OBJECT_LIST(DEFINE_IS)
-HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(DEFINE_IS)
-#undef DEFINE_IS
-
-#define DEFINE_AS(Name)                    \
+  }                                                                     \
  Name##Data* ObjectData::As##Name() {                                  \
    CHECK(Is##Name());                                                  \
    return static_cast<Name##Data*>(this);                              \
  }
-HEAP_BROKER_SERIALIZED_OBJECT_LIST(DEFINE_AS)
-#undef DEFINE_AS
+HEAP_BROKER_OBJECT_LIST(DEFINE_IS_AND_AS)
+#undef DEFINE_IS_AND_AS

 const JSObjectField& JSObjectData::GetInobjectField(int property_index) const {
  CHECK_LT(static_cast<size_t>(property_index), inobject_fields_.size());
@ -2652,20 +2683,15 @@ ObjectData* JSHeapBroker::GetOrCreateData(Handle<Object> object) {
    } else if (IsReadOnlyHeapObject(*object)) {
      object_data = zone()->New<ObjectData>(this, data_storage, object,
                                            kUnserializedReadOnlyHeapObject);
-#define CREATE_DATA_FOR_DIRECT_READ(name)    \
-    } else if (object->Is##name()) {         \
-      object_data = zone()->New<ObjectData>( \
-          this, data_storage, object, kNeverSerializedHeapObject);
-    HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(CREATE_DATA_FOR_DIRECT_READ)
-#undef CREATE_DATA_FOR_DIRECT_READ
-#define CREATE_DATA_FOR_SERIALIZATION(name)                     \
+#define CREATE_DATA_IF_MATCH(name)                              \
    } else if (object->Is##name()) {                            \
      CHECK(SerializingAllowed());                              \
      AllowHandleAllocation handle_allocation;                  \
      object_data = zone()->New<name##Data>(this, data_storage, \
                                            Handle<name>::cast(object));
-    HEAP_BROKER_SERIALIZED_OBJECT_LIST(CREATE_DATA_FOR_SERIALIZATION)
-#undef CREATE_DATA_FOR_SERIALIZATION
+
+      HEAP_BROKER_OBJECT_LIST(CREATE_DATA_IF_MATCH)
+#undef CREATE_DATA_IF_MATCH
    } else {
      UNREACHABLE();
    }
@ -2678,7 +2704,7 @@ ObjectData* JSHeapBroker::GetOrCreateData(Handle<Object> object) {
 // clang-format on

 ObjectData* JSHeapBroker::GetOrCreateData(Object object) {
-  return GetOrCreateData(CanonicalPersistentHandle(object));
+  return GetOrCreateData(handle(object, isolate()));
 }

 #define DEFINE_IS_AND_AS(Name)                                    \
@ -2687,8 +2713,7 @@ ObjectData* JSHeapBroker::GetOrCreateData(Object object) {
    DCHECK(Is##Name());                                           \
    return Name##Ref(broker(), data());                           \
  }
-HEAP_BROKER_SERIALIZED_OBJECT_LIST(DEFINE_IS_AND_AS)
-HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(DEFINE_IS_AND_AS)
+HEAP_BROKER_OBJECT_LIST(DEFINE_IS_AND_AS)
 #undef DEFINE_IS_AND_AS

 bool ObjectRef::IsSmi() const { return data()->is_smi(); }
@ -3232,6 +3257,8 @@ Handle<Object> JSHeapBroker::GetRootHandle(Object object) {

 #define IF_ACCESS_FROM_HEAP_C(holder, name)                              \
  if (data_->should_access_heap()) {                                     \
+    CHECK(broker()->mode() == JSHeapBroker::kDisabled ||                 \
+          ReadOnlyHeap::Contains(HeapObject::cast(*object())));          \
    AllowHandleAllocationIf handle_allocation(data_->kind(),             \
                                              broker()->mode());         \
    AllowHandleDereferenceIf allow_handle_dereference(data_->kind(),     \
@ -3252,9 +3279,6 @@ Handle<Object> JSHeapBroker::GetRootHandle(Object object) {
    AllowHandleDereferenceIf handle_dereference(data_->kind(),               \
                                                broker()->mode());           \
    return result##Ref(broker(), broker()->GetRootHandle(object()->name())); \
-  } else if (data_->kind() == ObjectDataKind::kNeverSerializedHeapObject) {    \
-    return result##Ref(broker(),                                               \
-                       broker()->CanonicalPersistentHandle(object()->name())); \
  }

 // Macros for definining a const getter that, depending on the broker mode,
@ -3589,22 +3613,39 @@ int MapRef::GetInObjectProperties() const {

 int ScopeInfoRef::ContextLength() const {
  IF_ACCESS_FROM_HEAP_C(ScopeInfo, ContextLength);
-  UNREACHABLE();
+  return data()->AsScopeInfo()->context_length();
 }

-bool ScopeInfoRef::HasContextExtensionSlot() const {
-  IF_ACCESS_FROM_HEAP_C(ScopeInfo, HasContextExtensionSlot);
-  UNREACHABLE();
+int ScopeInfoRef::Flags() const {
+  IF_ACCESS_FROM_HEAP_C(ScopeInfo, Flags);
+  return data()->AsScopeInfo()->flags();
+}
+
+bool ScopeInfoRef::HasContextExtension() const {
+  return ScopeInfo::HasContextExtensionSlotBit::decode(Flags());
 }

 bool ScopeInfoRef::HasOuterScopeInfo() const {
  IF_ACCESS_FROM_HEAP_C(ScopeInfo, HasOuterScopeInfo);
-  UNREACHABLE();
+  return data()->AsScopeInfo()->has_outer_scope_info();
 }

 ScopeInfoRef ScopeInfoRef::OuterScopeInfo() const {
-  IF_ACCESS_FROM_HEAP(ScopeInfo, ScopeInfo, OuterScopeInfo);
-  UNREACHABLE();
+  if (data_->should_access_heap()) {
+    DCHECK(data_->kind() != ObjectDataKind::kUnserializedReadOnlyHeapObject);
+    AllowHandleAllocationIf allow_handle_allocation(data()->kind(),
+                                                    broker()->mode());
+    AllowHandleDereferenceIf allow_handle_dereference(data()->kind(),
+                                                      broker()->mode());
+    return ScopeInfoRef(
+        broker(), handle(object()->OuterScopeInfo(), broker()->isolate()));
+  }
+  return ScopeInfoRef(broker(), data()->AsScopeInfo()->outer_scope_info());
+}
+
+void ScopeInfoRef::SerializeScopeInfoChain() {
+  CHECK_EQ(broker()->mode(), JSHeapBroker::kSerializing);
+  data()->AsScopeInfo()->SerializeScopeInfoChain(broker());
 }

 bool StringRef::IsExternalString() const {
@ -3645,8 +3686,8 @@ ScopeInfoRef NativeContextRef::scope_info() const {
                                                    broker()->mode());
    AllowHandleDereferenceIf allow_handle_dereference(data()->kind(),
                                                      broker()->mode());
-    return ScopeInfoRef(
-        broker(), broker()->CanonicalPersistentHandle(object()->scope_info()));
+    return ScopeInfoRef(broker(),
+                        handle(object()->scope_info(), broker()->isolate()));
  }
  return ScopeInfoRef(broker(), data()->AsNativeContext()->scope_info());
 }
@ -4081,8 +4122,7 @@ Handle<Object> ObjectRef::object() const {
  }
 #endif  // DEBUG

-HEAP_BROKER_SERIALIZED_OBJECT_LIST(DEF_OBJECT_GETTER)
-HEAP_BROKER_NEVER_SERIALIZED_OBJECT_LIST(DEF_OBJECT_GETTER)
+HEAP_BROKER_OBJECT_LIST(DEF_OBJECT_GETTER)
 #undef DEF_OBJECT_GETTER

 JSHeapBroker* ObjectRef::broker() const { return broker_; }
@ -4148,7 +4188,7 @@ void NativeContextData::Serialize(JSHeapBroker* broker) {
    function_maps_.push_back(broker->GetOrCreateData(context->get(i))->AsMap());
  }

-  scope_info_ = broker->GetOrCreateData(context->scope_info());
+  scope_info_ = broker->GetOrCreateData(context->scope_info())->AsScopeInfo();
 }

 void JSFunctionRef::Serialize() {
@ -4251,8 +4291,8 @@ ScopeInfoRef SharedFunctionInfoRef::scope_info() const {
                                                    broker()->mode());
    AllowHandleDereferenceIf allow_handle_dereference(data()->kind(),
                                                      broker()->mode());
-    return ScopeInfoRef(
-        broker(), broker()->CanonicalPersistentHandle(object()->scope_info()));
+    return ScopeInfoRef(broker(),
+                        handle(object()->scope_info(), broker()->isolate()));
  }
  return ScopeInfoRef(broker(), data()->AsSharedFunctionInfo()->scope_info());
 }
--- a/src/compiler/pipeline.cc
+++ b/src/compiler/pipeline.cc
@ -1508,9 +1508,6 @@ struct TyperPhase {
    roots.push_back(data->jsgraph()->TrueConstant());
    roots.push_back(data->jsgraph()->FalseConstant());

-    // The typer inspects heap objects, so we need to unpark the local heap.
-    UnparkedScopeIfNeeded scope(data->broker());
-
    LoopVariableOptimizer induction_vars(data->jsgraph()->graph(),
                                         data->common(), temp_zone);
    if (FLAG_turbo_loop_variable) induction_vars.Run();
--- a/src/compiler/serializer-for-background-compilation.cc
+++ b/src/compiler/serializer-for-background-compilation.cc
@ -1775,6 +1775,12 @@ void SerializerForBackgroundCompilation::VisitForInPrepare(

 void SerializerForBackgroundCompilation::ProcessCreateContext(
    interpreter::BytecodeArrayIterator* iterator, int scopeinfo_operand_index) {
+  Handle<ScopeInfo> scope_info =
+      Handle<ScopeInfo>::cast(iterator->GetConstantForIndexOperand(
+          scopeinfo_operand_index, broker()->isolate()));
+  ScopeInfoRef scope_info_ref(broker(), scope_info);
+  scope_info_ref.SerializeScopeInfoChain();
+
  Hints const& current_context_hints = environment()->current_context_hints();
  Hints result_hints;

--- a/src/objects/object-macros.h
+++ b/src/objects/object-macros.h
@ -79,11 +79,6 @@
 #define DECL_SYNCHRONIZED_INT_ACCESSORS(name) \
  DECL_SYNCHRONIZED_PRIMITIVE_ACCESSORS(name, int)

-#define DECL_SYNCHRONIZED_ACCESSORS(name, type) \
-  DECL_GETTER(synchronized_##name, type)        \
-  inline void set_synchronized_##name(          \
-      type value, WriteBarrierMode mode = UPDATE_WRITE_BARRIER);
-
 #define DECL_INT32_ACCESSORS(name) DECL_PRIMITIVE_ACCESSORS(name, int32_t)

 #define DECL_UINT16_ACCESSORS(name) \
--- a/src/objects/shared-function-info-inl.h
+++ b/src/objects/shared-function-info-inl.h
@ -101,8 +101,6 @@ SYNCHRONIZED_ACCESSORS(SharedFunctionInfo, function_data, Object,
                       kFunctionDataOffset)
 ACCESSORS(SharedFunctionInfo, name_or_scope_info, Object,
          kNameOrScopeInfoOffset)
-SYNCHRONIZED_ACCESSORS(SharedFunctionInfo, synchronized_name_or_scope_info,
-                       Object, kNameOrScopeInfoOffset)
 ACCESSORS(SharedFunctionInfo, script_or_debug_info, HeapObject,
          kScriptOrDebugInfoOffset)

@ -340,15 +338,7 @@ ScopeInfo SharedFunctionInfo::scope_info() const {
  return GetReadOnlyRoots().empty_scope_info();
 }

-ScopeInfo SharedFunctionInfo::synchronized_scope_info() const {
-  Object maybe_scope_info = synchronized_name_or_scope_info();
-  if (maybe_scope_info.IsScopeInfo()) {
-    return ScopeInfo::cast(maybe_scope_info);
-  }
-  return GetReadOnlyRoots().empty_scope_info();
-}
-
-void SharedFunctionInfo::SetScopeInfo(ScopeInfo scope_info,
+void SharedFunctionInfo::set_scope_info(ScopeInfo scope_info,
                                        WriteBarrierMode mode) {
  // Move the existing name onto the ScopeInfo.
  Object name = name_or_scope_info();
@ -361,7 +351,7 @@ void SharedFunctionInfo::SetScopeInfo(ScopeInfo scope_info,
  if (HasInferredName() && inferred_name().length() != 0) {
    scope_info.SetInferredFunctionName(inferred_name());
  }
-  set_synchronized_name_or_scope_info(scope_info, mode);
+  set_raw_scope_info(scope_info, mode);
 }

 void SharedFunctionInfo::set_raw_scope_info(ScopeInfo scope_info,
--- a/src/objects/shared-function-info.h
+++ b/src/objects/shared-function-info.h
@ -216,16 +216,12 @@ class SharedFunctionInfo : public HeapObject {
  static const int kNotFound = -1;

  // [scope_info]: Scope info.
-  DECL_GETTER(scope_info, ScopeInfo)
-  DECL_GETTER(synchronized_scope_info, ScopeInfo)
+  DECL_ACCESSORS(scope_info, ScopeInfo)

  // Set scope_info without moving the existing name onto the ScopeInfo.
  inline void set_raw_scope_info(ScopeInfo scope_info,
                                 WriteBarrierMode mode = UPDATE_WRITE_BARRIER);

-  inline void SetScopeInfo(ScopeInfo scope_info,
-                           WriteBarrierMode mode = UPDATE_WRITE_BARRIER);
-
  inline bool is_script() const;
  inline bool needs_script_context() const;

@ -666,7 +662,6 @@ class SharedFunctionInfo : public HeapObject {
  // [name_or_scope_info]: Function name string, kNoSharedNameSentinel or
  // ScopeInfo.
  DECL_ACCESSORS(name_or_scope_info, Object)
-  DECL_SYNCHRONIZED_ACCESSORS(name_or_scope_info, Object)

  // [outer scope info] The outer scope info, needed to lazily parse this
  // function.