Revert "[offthread] Add SFI support to OffThreadFactory"

This reverts commit 453e1a3b.

Reason for revert: Makes UBSan unhappy - https://ci.chromium.org/p/v8/builders/ci/V8%20Linux64%20UBSan/9893

Original change's description:
> [offthread] Add SFI support to OffThreadFactory
> 
> Add support for off-thread SharedFunctionInfo allocation, which
> includes UncompiledData and PreparseData allocation.
> 
> Bug: chromium:1011762
> Change-Id: Ia10f9ce762c7d7eb1108b9e71da75131dce919b7
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2050393
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#66246}

TBR=ulan@chromium.org,leszeks@chromium.org,ishell@chromium.org

Change-Id: I26bc40ec1c351613f19745aed83f0c3a9fdd9a20
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:1011762
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2052172Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66247}

src/ast/ast.h

@@ -15,7 +15,6 @@
 #include "src/codegen/label.h"
 #include "src/common/globals.h"
 #include "src/execution/isolate.h"
-#include "src/execution/off-thread-isolate.h"
 #include "src/heap/factory.h"
 #include "src/objects/elements-kind.h"
 #include "src/objects/function-syntax-kind.h"
@@ -2209,10 +2208,8 @@ class FunctionLiteral final : public Expression {
 
   // Empty handle means that the function does not have a shared name (i.e.
   // the name will be set dynamically after creation of the function closure).
-  template <typename Isolate>
-  MaybeHandleFor<Isolate, String> GetName(Isolate* isolate) const {
-    return raw_name_ ? raw_name_->AllocateFlat(isolate)
-                     : MaybeHandleFor<Isolate, String>();
+  MaybeHandle<String> GetName(Isolate* isolate) const {
+    return raw_name_ ? raw_name_->AllocateFlat(isolate) : MaybeHandle<String>();
   }
   bool has_shared_name() const { return raw_name_ != nullptr; }
   const AstConsString* raw_name() const { return raw_name_; }
@@ -2280,11 +2277,6 @@ class FunctionLiteral final : public Expression {
     }
     UNREACHABLE();
   }
-  OffThreadHandle<String> GetInferredName(OffThreadIsolate* isolate) const {
-    DCHECK(inferred_name_.is_null());
-    DCHECK_NOT_NULL(raw_inferred_name_);
-    return raw_inferred_name_->GetString(isolate);
-  }
   const AstConsString* raw_inferred_name() { return raw_inferred_name_; }
 
   // Only one of {set_inferred_name, set_raw_inferred_name} should be called.

src/diagnostics/objects-debug.cc

@@ -32,7 +32,6 @@
 #include "src/objects/js-array-inl.h"
 #include "src/objects/layout-descriptor.h"
 #include "src/objects/objects-inl.h"
-#include "src/roots/roots.h"
 #ifdef V8_INTL_SUPPORT
 #include "src/objects/js-break-iterator-inl.h"
 #include "src/objects/js-collator-inl.h"
@@ -817,20 +816,12 @@ void JSFunction::JSFunctionVerify(Isolate* isolate) {
 }
 
 void SharedFunctionInfo::SharedFunctionInfoVerify(Isolate* isolate) {
-  // TODO(leszeks): Add a TorqueGeneratedClassVerifier for OffThreadIsolate.
   TorqueGeneratedClassVerifiers::SharedFunctionInfoVerify(*this, isolate);
-  this->SharedFunctionInfoVerify(ReadOnlyRoots(isolate));
-}
-
-void SharedFunctionInfo::SharedFunctionInfoVerify(OffThreadIsolate* isolate) {
-  this->SharedFunctionInfoVerify(ReadOnlyRoots(isolate));
-}
 
-void SharedFunctionInfo::SharedFunctionInfoVerify(ReadOnlyRoots roots) {
   Object value = name_or_scope_info();
   if (value.IsScopeInfo()) {
     CHECK_LT(0, ScopeInfo::cast(value).length());
-    CHECK_NE(value, roots.empty_scope_info());
+    CHECK_NE(value, ReadOnlyRoots(isolate).empty_scope_info());
   }
 
   CHECK(HasWasmExportedFunctionData() || IsApiFunction() ||
@@ -839,13 +830,13 @@ void SharedFunctionInfo::SharedFunctionInfoVerify(ReadOnlyRoots roots) {
         HasUncompiledDataWithoutPreparseData() || HasWasmJSFunctionData() ||
         HasWasmCapiFunctionData());
 
-  CHECK(script_or_debug_info().IsUndefined(roots) ||
+  CHECK(script_or_debug_info().IsUndefined(isolate) ||
         script_or_debug_info().IsScript() || HasDebugInfo());
 
   if (!is_compiled()) {
     CHECK(!HasFeedbackMetadata());
     CHECK(outer_scope_info().IsScopeInfo() ||
-          outer_scope_info().IsTheHole(roots));
+          outer_scope_info().IsTheHole(isolate));
   } else if (HasBytecodeArray() && HasFeedbackMetadata()) {
     CHECK(feedback_metadata().IsFeedbackMetadata());
   }

src/execution/isolate.h

@@ -1290,19 +1290,7 @@ class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
   int GetNextScriptId();
 
 #if V8_SFI_HAS_UNIQUE_ID
-  int GetNextUniqueSharedFunctionInfoId() {
-    int current_id = next_unique_sfi_id_.load(std::memory_order_relaxed);
-    int next_id;
-    do {
-      if (current_id >= Smi::kMaxValue) {
-        next_id = 0;
-      } else {
-        next_id = current_id + 1;
-      }
-    } while (!next_unique_sfi_id_.compare_exchange_weak(
-        current_id, next_id, std::memory_order_relaxed));
-    return current_id;
-  }
+  int GetNextUniqueSharedFunctionInfoId() { return next_unique_sfi_id_++; }
 #endif
 
   Address promise_hook_address() {
@@ -1777,7 +1765,7 @@ class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
   int next_optimization_id_ = 0;
 
 #if V8_SFI_HAS_UNIQUE_ID
-  std::atomic<int> next_unique_sfi_id_;
+  int next_unique_sfi_id_ = 0;
 #endif
 
   // Vector of callbacks before a Call starts execution.

src/execution/off-thread-isolate.cc

@@ -18,12 +18,6 @@ OffThreadIsolate::~OffThreadIsolate() { delete logger_; }
 
 int OffThreadIsolate::GetNextScriptId() { return isolate_->GetNextScriptId(); }
 
-#if V8_SFI_HAS_UNIQUE_ID
-int OffThreadIsolate::GetNextUniqueSharedFunctionInfoId() {
-  return isolate_->GetNextUniqueSharedFunctionInfoId();
-}
-#endif  // V8_SFI_HAS_UNIQUE_ID
-
 bool OffThreadIsolate::NeedsSourcePositionsForProfiling() {
   // TODO(leszeks): Figure out if it makes sense to check this asynchronously.
   return isolate_->NeedsSourcePositionsForProfiling();

src/execution/off-thread-isolate.h

@@ -61,9 +61,6 @@ class V8_EXPORT_PRIVATE OffThreadIsolate final
   }
 
   int GetNextScriptId();
-#if V8_SFI_HAS_UNIQUE_ID
-  int GetNextUniqueSharedFunctionInfoId();
-#endif  // V8_SFI_HAS_UNIQUE_ID
 
   bool NeedsSourcePositionsForProfiling();
   bool is_collecting_type_profile();

src/handles/handles.h

@@ -233,7 +233,7 @@ class OffThreadHandle {
   }
 
  private:
-  Address address_ = 0;
+  Address address_;
 };
 
 // A helper class which wraps an normal or off-thread handle, and returns one

src/heap/factory-base.cc

@@ -114,35 +114,6 @@ HandleFor<Impl, FixedArrayBase> FactoryBase<Impl>::NewFixedDoubleArray(
   return array;
 }
 
-template <typename Impl>
-HandleFor<Impl, WeakFixedArray> FactoryBase<Impl>::NewWeakFixedArrayWithMap(
-    Map map, int length, AllocationType allocation) {
-  // Zero-length case must be handled outside.
-  DCHECK_LT(0, length);
-  DCHECK(ReadOnlyHeap::Contains(map));
-
-  HeapObject result =
-      AllocateRawArray(WeakFixedArray::SizeFor(length), allocation);
-  result.set_map_after_allocation(map, SKIP_WRITE_BARRIER);
-
-  HandleFor<Impl, WeakFixedArray> array =
-      handle(WeakFixedArray::cast(result), isolate());
-  array->set_length(length);
-  MemsetTagged(ObjectSlot(array->data_start()),
-               read_only_roots().undefined_value(), length);
-
-  return array;
-}
-
-template <typename Impl>
-HandleFor<Impl, WeakFixedArray> FactoryBase<Impl>::NewWeakFixedArray(
-    int length, AllocationType allocation) {
-  DCHECK_LE(0, length);
-  if (length == 0) return impl()->empty_weak_fixed_array();
-  return NewWeakFixedArrayWithMap(read_only_roots().weak_fixed_array_map(),
-                                  length, allocation);
-}
-
 template <typename Impl>
 HandleFor<Impl, Script> FactoryBase<Impl>::NewScript(
     HandleFor<Impl, String> source) {
@@ -177,111 +148,6 @@ HandleFor<Impl, Script> FactoryBase<Impl>::NewScriptWithId(
   return script;
 }
 
-template <typename Impl>
-HandleFor<Impl, SharedFunctionInfo>
-FactoryBase<Impl>::NewSharedFunctionInfoForLiteral(
-    FunctionLiteral* literal, HandleFor<Impl, Script> script,
-    bool is_toplevel) {
-  FunctionKind kind = literal->kind();
-  HandleFor<Impl, SharedFunctionInfo> shared = NewSharedFunctionInfo(
-      literal->GetName(isolate()), MaybeHandleFor<Impl, Code>(),
-      Builtins::kCompileLazy, kind);
-  SharedFunctionInfo::InitFromFunctionLiteral(isolate(), shared, literal,
-                                              is_toplevel);
-  shared->SetScript(read_only_roots(), *script, literal->function_literal_id(),
-                    false);
-  return shared;
-}
-
-template <typename Impl>
-HandleFor<Impl, PreparseData> FactoryBase<Impl>::NewPreparseData(
-    int data_length, int children_length) {
-  int size = PreparseData::SizeFor(data_length, children_length);
-  HandleFor<Impl, PreparseData> result = handle(
-      PreparseData::cast(AllocateRawWithImmortalMap(
-          size, AllocationType::kOld, read_only_roots().preparse_data_map())),
-      isolate());
-  result->set_data_length(data_length);
-  result->set_children_length(children_length);
-  MemsetTagged(result->inner_data_start(), read_only_roots().null_value(),
-               children_length);
-  result->clear_padding();
-  return result;
-}
-
-template <typename Impl>
-HandleFor<Impl, UncompiledDataWithoutPreparseData>
-FactoryBase<Impl>::NewUncompiledDataWithoutPreparseData(
-    HandleFor<Impl, String> inferred_name, int32_t start_position,
-    int32_t end_position) {
-  HandleFor<Impl, UncompiledDataWithoutPreparseData> result = handle(
-      UncompiledDataWithoutPreparseData::cast(NewWithImmortalMap(
-          impl()->read_only_roots().uncompiled_data_without_preparse_data_map(),
-          AllocationType::kOld)),
-      isolate());
-
-  result->Init(impl(), *inferred_name, start_position, end_position);
-  return result;
-}
-
-template <typename Impl>
-HandleFor<Impl, UncompiledDataWithPreparseData>
-FactoryBase<Impl>::NewUncompiledDataWithPreparseData(
-    HandleFor<Impl, String> inferred_name, int32_t start_position,
-    int32_t end_position, HandleFor<Impl, PreparseData> preparse_data) {
-  HandleFor<Impl, UncompiledDataWithPreparseData> result = handle(
-      UncompiledDataWithPreparseData::cast(NewWithImmortalMap(
-          impl()->read_only_roots().uncompiled_data_with_preparse_data_map(),
-          AllocationType::kOld)),
-      isolate());
-
-  result->Init(impl(), *inferred_name, start_position, end_position,
-               *preparse_data);
-
-  return result;
-}
-
-template <typename Impl>
-HandleFor<Impl, SharedFunctionInfo> FactoryBase<Impl>::NewSharedFunctionInfo(
-    MaybeHandleFor<Impl, String> maybe_name,
-    MaybeHandleFor<Impl, HeapObject> maybe_function_data,
-    int maybe_builtin_index, FunctionKind kind) {
-  HandleFor<Impl, SharedFunctionInfo> shared = NewSharedFunctionInfo();
-
-  // Function names are assumed to be flat elsewhere.
-  HandleFor<Impl, String> shared_name;
-  bool has_shared_name = maybe_name.ToHandle(&shared_name);
-  if (has_shared_name) {
-    DCHECK(shared_name->IsFlat());
-    shared->set_name_or_scope_info(*shared_name);
-  } else {
-    DCHECK_EQ(shared->name_or_scope_info(),
-              SharedFunctionInfo::kNoSharedNameSentinel);
-  }
-
-  HandleFor<Impl, HeapObject> function_data;
-  if (maybe_function_data.ToHandle(&function_data)) {
-    // If we pass function_data then we shouldn't pass a builtin index, and
-    // the function_data should not be code with a builtin.
-    DCHECK(!Builtins::IsBuiltinId(maybe_builtin_index));
-    DCHECK_IMPLIES(function_data->IsCode(),
-                   !Code::cast(*function_data).is_builtin());
-    shared->set_function_data(*function_data);
-  } else if (Builtins::IsBuiltinId(maybe_builtin_index)) {
-    shared->set_builtin_id(maybe_builtin_index);
-  } else {
-    shared->set_builtin_id(Builtins::kIllegal);
-  }
-
-  shared->CalculateConstructAsBuiltin();
-  shared->set_kind(kind);
-
-#ifdef VERIFY_HEAP
-  shared->SharedFunctionInfoVerify(isolate());
-#endif  // VERIFY_HEAP
-  return shared;
-}
-
 template <typename Impl>
 HandleFor<Impl, ObjectBoilerplateDescription>
 FactoryBase<Impl>::NewObjectBoilerplateDescription(int boilerplate,
@@ -537,26 +403,6 @@ FactoryBase<Impl>::NewSourceTextModuleInfo() {
       AllocationType::kOld));
 }
 
-template <typename Impl>
-HandleFor<Impl, SharedFunctionInfo> FactoryBase<Impl>::NewSharedFunctionInfo() {
-  Map map = read_only_roots().shared_function_info_map();
-
-  HandleFor<Impl, SharedFunctionInfo> shared = handle(
-      SharedFunctionInfo::cast(NewWithImmortalMap(map, AllocationType::kOld)),
-      isolate());
-  int unique_id = -1;
-#if V8_SFI_HAS_UNIQUE_ID
-  unique_id = isolate()->GetNextUniqueSharedFunctionInfoId();
-#endif  // V8_SFI_HAS_UNIQUE_ID
-
-  shared->Init(read_only_roots(), unique_id);
-
-#ifdef VERIFY_HEAP
-  shared->SharedFunctionInfoVerify(isolate());
-#endif  // VERIFY_HEAP
-  return shared;
-}
-
 template <typename Impl>
 HandleFor<Impl, SeqOneByteString>
 FactoryBase<Impl>::AllocateRawOneByteInternalizedString(int length,

src/heap/factory-base.h

@@ -8,7 +8,6 @@
 #include "src/base/export-template.h"
 #include "src/common/globals.h"
 #include "src/handles/handle-for.h"
-#include "src/objects/function-kind.h"
 #include "src/objects/instance-type.h"
 #include "src/roots/roots.h"
 
@@ -16,8 +15,6 @@ namespace v8 {
 namespace internal {
 
 class HeapObject;
-class SharedFunctionInfo;
-class FunctionLiteral;
 class SeqOneByteString;
 class SeqTwoByteString;
 class FreshlyAllocatedBigInt;
@@ -25,9 +22,6 @@ class ObjectBoilerplateDescription;
 class ArrayBoilerplateDescription;
 class TemplateObjectDescription;
 class SourceTextModuleInfo;
-class PreparseData;
-class UncompiledDataWithoutPreparseData;
-class UncompiledDataWithPreparseData;
 
 template <typename Impl>
 class EXPORT_TEMPLATE_DECLARE(V8_EXPORT_PRIVATE) FactoryBase {
@@ -79,16 +73,6 @@ class EXPORT_TEMPLATE_DECLARE(V8_EXPORT_PRIVATE) FactoryBase {
   HandleFor<Impl, FixedArrayBase> NewFixedDoubleArray(
       int length, AllocationType allocation = AllocationType::kYoung);
 
-  // Allocates a weak fixed array-like object with given map and initialized
-  // with undefined values.
-  HandleFor<Impl, WeakFixedArray> NewWeakFixedArrayWithMap(
-      Map map, int length, AllocationType allocation = AllocationType::kYoung);
-
-  // Allocates a fixed array which may contain in-place weak references. The
-  // array is initialized with undefined values
-  HandleFor<Impl, WeakFixedArray> NewWeakFixedArray(
-      int length, AllocationType allocation = AllocationType::kYoung);
-
   // Allocates a fixed array for name-value pairs of boilerplate properties and
   // calculates the number of properties we need to store in the backing store.
   HandleFor<Impl, ObjectBoilerplateDescription> NewObjectBoilerplateDescription(
@@ -108,24 +92,6 @@ class EXPORT_TEMPLATE_DECLARE(V8_EXPORT_PRIVATE) FactoryBase {
   HandleFor<Impl, Script> NewScriptWithId(HandleFor<Impl, String> source,
                                           int script_id);
 
-  HandleFor<Impl, SharedFunctionInfo> NewSharedFunctionInfoForLiteral(
-      FunctionLiteral* literal, HandleFor<Impl, Script> script,
-      bool is_toplevel);
-
-  HandleFor<Impl, PreparseData> NewPreparseData(int data_length,
-                                                int children_length);
-
-  HandleFor<Impl, UncompiledDataWithoutPreparseData>
-  NewUncompiledDataWithoutPreparseData(HandleFor<Impl, String> inferred_name,
-                                       int32_t start_position,
-                                       int32_t end_position);
-
-  HandleFor<Impl, UncompiledDataWithPreparseData>
-  NewUncompiledDataWithPreparseData(HandleFor<Impl, String> inferred_name,
-                                    int32_t start_position,
-                                    int32_t end_position,
-                                    HandleFor<Impl, PreparseData>);
-
   HandleFor<Impl, SeqOneByteString> NewOneByteInternalizedString(
       const Vector<const uint8_t>& str, uint32_t hash_field);
   HandleFor<Impl, SeqTwoByteString> NewTwoByteInternalizedString(
@@ -179,12 +145,6 @@ class EXPORT_TEMPLATE_DECLARE(V8_EXPORT_PRIVATE) FactoryBase {
   HandleFor<Impl, FixedArray> NewFixedArrayWithFiller(
       Map map, int length, Oddball filler, AllocationType allocation);
 
-  HandleFor<Impl, SharedFunctionInfo> NewSharedFunctionInfo();
-  HandleFor<Impl, SharedFunctionInfo> NewSharedFunctionInfo(
-      MaybeHandleFor<Impl, String> maybe_name,
-      MaybeHandleFor<Impl, HeapObject> maybe_function_data,
-      int maybe_builtin_index, FunctionKind kind = kNormalFunction);
-
  private:
   Impl* impl() { return static_cast<Impl*>(this); }
   auto isolate() { return impl()->isolate(); }

src/heap/factory.cc

@@ -10,6 +10,7 @@
 #include <utility>  // For move
 
 #include "src/ast/ast-source-ranges.h"
+#include "src/ast/ast.h"
 #include "src/base/bits.h"
 #include "src/builtins/accessors.h"
 #include "src/builtins/constants-table-builder.h"
@@ -340,6 +341,40 @@ Handle<FixedArray> Factory::NewFixedArrayWithMapRootIndex(
                               length, allocation);
 }
 
+template <typename T>
+Handle<T> Factory::NewWeakFixedArrayWithMap(Map map, int length,
+                                            AllocationType allocation) {
+  static_assert(std::is_base_of<WeakFixedArray, T>::value,
+                "T must be a descendant of WeakFixedArray");
+
+  // Zero-length case must be handled outside.
+  DCHECK_LT(0, length);
+
+  HeapObject result =
+      AllocateRawArray(WeakFixedArray::SizeFor(length), AllocationType::kOld);
+  result.set_map_after_allocation(map, SKIP_WRITE_BARRIER);
+
+  Handle<WeakFixedArray> array(WeakFixedArray::cast(result), isolate());
+  array->set_length(length);
+  MemsetTagged(ObjectSlot(array->data_start()), *undefined_value(), length);
+
+  return Handle<T>::cast(array);
+}
+
+Handle<WeakFixedArray> Factory::NewWeakFixedArray(int length,
+                                                  AllocationType allocation) {
+  DCHECK_LE(0, length);
+  if (length == 0) return empty_weak_fixed_array();
+  HeapObject result =
+      AllocateRawArray(WeakFixedArray::SizeFor(length), allocation);
+  result.set_map_after_allocation(read_only_roots().weak_fixed_array_map(),
+                                  SKIP_WRITE_BARRIER);
+  Handle<WeakFixedArray> array(WeakFixedArray::cast(result), isolate());
+  array->set_length(length);
+  MemsetTagged(ObjectSlot(array->data_start()), *undefined_value(), length);
+  return array;
+}
+
 MaybeHandle<FixedArray> Factory::TryNewFixedArray(
     int length, AllocationType allocation_type) {
   DCHECK_LE(0, length);
@@ -1447,9 +1482,8 @@ Handle<DescriptorArray> Factory::NewDescriptorArray(int number_of_descriptors,
 Handle<TransitionArray> Factory::NewTransitionArray(int number_of_transitions,
                                                     int slack) {
   int capacity = TransitionArray::LengthFor(number_of_transitions + slack);
-  Handle<TransitionArray> array = Handle<TransitionArray>::cast(
-      NewWeakFixedArrayWithMap(read_only_roots().transition_array_map(),
-                               capacity, AllocationType::kOld));
+  Handle<TransitionArray> array = NewWeakFixedArrayWithMap<TransitionArray>(
+      read_only_roots().transition_array_map(), capacity, AllocationType::kOld);
   // Transition arrays are AllocationType::kOld. When black allocation is on we
   // have to add the transition array to the list of
   // encountered_transition_arrays.
@@ -2096,6 +2130,48 @@ Handle<JSFunction> Factory::NewFunctionFromSharedFunctionInfo(
   return result;
 }
 
+Handle<PreparseData> Factory::NewPreparseData(int data_length,
+                                              int children_length) {
+  int size = PreparseData::SizeFor(data_length, children_length);
+  Handle<PreparseData> result(
+      PreparseData::cast(AllocateRawWithImmortalMap(size, AllocationType::kOld,
+                                                    *preparse_data_map())),
+      isolate());
+  result->set_data_length(data_length);
+  result->set_children_length(children_length);
+  MemsetTagged(result->inner_data_start(), *null_value(), children_length);
+  result->clear_padding();
+  return result;
+}
+
+Handle<UncompiledDataWithoutPreparseData>
+Factory::NewUncompiledDataWithoutPreparseData(Handle<String> inferred_name,
+                                              int32_t start_position,
+                                              int32_t end_position) {
+  Handle<UncompiledDataWithoutPreparseData> result(
+      UncompiledDataWithoutPreparseData::cast(New(
+          uncompiled_data_without_preparse_data_map(), AllocationType::kOld)),
+      isolate());
+
+  result->Init(*inferred_name, start_position, end_position);
+  return result;
+}
+
+Handle<UncompiledDataWithPreparseData>
+Factory::NewUncompiledDataWithPreparseData(Handle<String> inferred_name,
+                                           int32_t start_position,
+                                           int32_t end_position,
+                                           Handle<PreparseData> preparse_data) {
+  Handle<UncompiledDataWithPreparseData> result(
+      UncompiledDataWithPreparseData::cast(
+          New(uncompiled_data_with_preparse_data_map(), AllocationType::kOld)),
+      isolate());
+
+  result->Init(*inferred_name, start_position, end_position, *preparse_data);
+
+  return result;
+}
+
 Handle<JSObject> Factory::NewExternal(void* value) {
   Handle<Foreign> foreign = NewForeign(reinterpret_cast<Address>(value));
   Handle<JSObject> external = NewJSObjectFromMap(external_map());
@@ -2889,6 +2965,18 @@ void Factory::ReinitializeJSGlobalProxy(Handle<JSGlobalProxy> object,
   InitializeJSObjectFromMap(object, raw_properties_or_hash, map);
 }
 
+Handle<SharedFunctionInfo> Factory::NewSharedFunctionInfoForLiteral(
+    FunctionLiteral* literal, Handle<Script> script, bool is_toplevel) {
+  FunctionKind kind = literal->kind();
+  Handle<SharedFunctionInfo> shared = NewSharedFunctionInfoForBuiltin(
+      literal->GetName(isolate()), Builtins::kCompileLazy, kind);
+  SharedFunctionInfo::InitFromFunctionLiteral(isolate(), shared, literal,
+                                              is_toplevel);
+  shared->SetScript(ReadOnlyRoots(isolate()), *script,
+                    literal->function_literal_id(), false);
+  return shared;
+}
+
 Handle<JSMessageObject> Factory::NewJSMessageObject(
     MessageTemplate message, Handle<Object> argument, int start_position,
     int end_position, Handle<SharedFunctionInfo> shared_info,
@@ -2948,6 +3036,64 @@ Handle<SharedFunctionInfo> Factory::NewSharedFunctionInfoForBuiltin(
   return shared;
 }
 
+Handle<SharedFunctionInfo> Factory::NewSharedFunctionInfo(
+    MaybeHandle<String> maybe_name, MaybeHandle<HeapObject> maybe_function_data,
+    int maybe_builtin_index, FunctionKind kind) {
+  Handle<SharedFunctionInfo> shared = NewSharedFunctionInfo();
+
+  // Function names are assumed to be flat elsewhere. Must flatten before
+  // allocating SharedFunctionInfo to avoid GC seeing the uninitialized SFI.
+  Handle<String> shared_name;
+  bool has_shared_name = maybe_name.ToHandle(&shared_name);
+  if (has_shared_name) {
+    DCHECK(shared_name->IsFlat());
+    shared->set_name_or_scope_info(*shared_name);
+  } else {
+    DCHECK_EQ(shared->name_or_scope_info(),
+              SharedFunctionInfo::kNoSharedNameSentinel);
+  }
+
+  Handle<HeapObject> function_data;
+  if (maybe_function_data.ToHandle(&function_data)) {
+    // If we pass function_data then we shouldn't pass a builtin index, and
+    // the function_data should not be code with a builtin.
+    DCHECK(!Builtins::IsBuiltinId(maybe_builtin_index));
+    DCHECK_IMPLIES(function_data->IsCode(),
+                   !Code::cast(*function_data).is_builtin());
+    shared->set_function_data(*function_data);
+  } else if (Builtins::IsBuiltinId(maybe_builtin_index)) {
+    shared->set_builtin_id(maybe_builtin_index);
+  } else {
+    shared->set_builtin_id(Builtins::kIllegal);
+  }
+
+  shared->CalculateConstructAsBuiltin();
+  shared->set_kind(kind);
+
+#ifdef VERIFY_HEAP
+  shared->SharedFunctionInfoVerify(isolate());
+#endif  // VERIFY_HEAP
+  return shared;
+}
+
+Handle<SharedFunctionInfo> Factory::NewSharedFunctionInfo() {
+  Handle<Map> map = shared_function_info_map();
+
+  Handle<SharedFunctionInfo> shared(
+      SharedFunctionInfo::cast(New(map, AllocationType::kOld)), isolate());
+  int unique_id = -1;
+#if V8_SFI_HAS_UNIQUE_ID
+  unique_id = isolate()->GetNextUniqueSharedFunctionInfoId();
+#endif  // V8_SFI_HAS_UNIQUE_ID
+
+  shared->Init(ReadOnlyRoots(isolate()), unique_id);
+
+#ifdef VERIFY_HEAP
+  shared->SharedFunctionInfoVerify(isolate());
+#endif  // VERIFY_HEAP
+  return shared;
+}
+
 namespace {
 inline int NumberToStringCacheHash(Handle<FixedArray> cache, Smi number) {
   int mask = (cache->length() >> 1) - 1;

src/heap/factory.h

@@ -16,6 +16,7 @@
 #include "src/heap/heap.h"
 #include "src/objects/code.h"
 #include "src/objects/dictionary.h"
+#include "src/objects/function-kind.h"
 #include "src/objects/js-array.h"
 #include "src/objects/js-regexp.h"
 #include "src/objects/string.h"
@@ -54,6 +55,7 @@ class JSWeakMap;
 class LoadHandler;
 class NativeContext;
 class NewFunctionArgs;
+class PreparseData;
 class PromiseResolveThenableJobTask;
 class RegExpMatchInfo;
 class ScriptContextTable;
@@ -63,6 +65,8 @@ class StackTraceFrame;
 class StoreHandler;
 class SyntheticModule;
 class TemplateObjectDescription;
+class UncompiledDataWithoutPreparseData;
+class UncompiledDataWithPreparseData;
 class WasmCapiFunctionData;
 class WasmExportedFunctionData;
 class WasmJSFunctionData;
@@ -130,6 +134,17 @@ class V8_EXPORT_PRIVATE Factory : public FactoryBase<Factory> {
       RootIndex map_root_index, int length,
       AllocationType allocation = AllocationType::kYoung);
 
+  // Allocates a weak fixed array-like object with given map and initialized
+  // with undefined values.
+  template <typename T = WeakFixedArray>
+  Handle<T> NewWeakFixedArrayWithMap(
+      Map map, int length, AllocationType allocation = AllocationType::kYoung);
+
+  // Allocates a fixed array which may contain in-place weak references. The
+  // array is initialized with undefined values
+  Handle<WeakFixedArray> NewWeakFixedArray(
+      int length, AllocationType allocation = AllocationType::kYoung);
+
   // Allocates a property array initialized with undefined values.
   Handle<PropertyArray> NewPropertyArray(int length);
   // Tries allocating a fixed array initialized with undefined values.
@@ -659,6 +674,17 @@ class V8_EXPORT_PRIVATE Factory : public FactoryBase<Factory> {
       Handle<Map> map, Handle<SharedFunctionInfo> info, Handle<Context> context,
       AllocationType allocation = AllocationType::kOld);
 
+  Handle<PreparseData> NewPreparseData(int data_length, int children_length);
+
+  Handle<UncompiledDataWithoutPreparseData>
+  NewUncompiledDataWithoutPreparseData(Handle<String> inferred_name,
+                                       int32_t start_position,
+                                       int32_t end_position);
+
+  Handle<UncompiledDataWithPreparseData> NewUncompiledDataWithPreparseData(
+      Handle<String> inferred_name, int32_t start_position,
+      int32_t end_position, Handle<PreparseData>);
+
   // Create an External object for V8's external API.
   Handle<JSObject> NewExternal(void* value);
 
@@ -732,6 +758,9 @@ class V8_EXPORT_PRIVATE Factory : public FactoryBase<Factory> {
       MaybeHandle<String> name, int builtin_index,
       FunctionKind kind = kNormalFunction);
 
+  Handle<SharedFunctionInfo> NewSharedFunctionInfoForLiteral(
+      FunctionLiteral* literal, Handle<Script> script, bool is_toplevel);
+
   static bool IsFunctionModeWithPrototype(FunctionMode function_mode) {
     return (function_mode & kWithPrototypeBits) != 0;
   }
@@ -980,6 +1009,11 @@ class V8_EXPORT_PRIVATE Factory : public FactoryBase<Factory> {
       ElementsKind elements_kind, int capacity,
       ArrayStorageAllocationMode mode = DONT_INITIALIZE_ARRAY_ELEMENTS);
 
+  Handle<SharedFunctionInfo> NewSharedFunctionInfo();
+  Handle<SharedFunctionInfo> NewSharedFunctionInfo(
+      MaybeHandle<String> name, MaybeHandle<HeapObject> maybe_function_data,
+      int maybe_builtin_index, FunctionKind kind = kNormalFunction);
+
   void InitializeAllocationMemento(AllocationMemento memento,
                                    AllocationSite allocation_site);
 

src/heap/mark-compact.cc

@@ -2217,7 +2217,7 @@ void MarkCompactCollector::FlushBytecodeFromSFI(
 
   // Initialize the uncompiled data.
   UncompiledData uncompiled_data = UncompiledData::cast(compiled_data);
-  uncompiled_data.InitAfterBytecodeFlush(
+  uncompiled_data.Init(
       inferred_name, start_position, end_position,
       [](HeapObject object, ObjectSlot slot, HeapObject target) {
         RecordSlot(object, slot, target);

src/heap/off-thread-factory.cc

@@ -16,7 +16,6 @@
 #include "src/objects/heap-object.h"
 #include "src/objects/map-inl.h"
 #include "src/objects/objects-body-descriptors-inl.h"
-#include "src/objects/shared-function-info.h"
 #include "src/objects/string.h"
 #include "src/objects/visitors.h"
 #include "src/roots/roots-inl.h"

src/heap/off-thread-factory.h

@@ -17,7 +17,6 @@
 #include "src/objects/heap-object.h"
 #include "src/objects/map.h"
 #include "src/objects/objects.h"
-#include "src/objects/shared-function-info.h"
 #include "src/roots/roots.h"
 
 namespace v8 {

src/objects/free-space-inl.h

@@ -37,8 +37,7 @@ void FreeSpace::set_next(FreeSpace next) {
 }
 
 FreeSpace FreeSpace::cast(HeapObject o) {
-  SLOW_DCHECK((!Heap::InOffThreadSpace(o) &&
-               !GetHeapFromWritableObject(o)->deserialization_complete()) ||
+  SLOW_DCHECK(!GetHeapFromWritableObject(o)->deserialization_complete() ||
               o.IsFreeSpace());
   return bit_cast<FreeSpace>(o);
 }

src/objects/objects.cc

@@ -33,7 +33,6 @@
 #include "src/execution/frames-inl.h"
 #include "src/execution/isolate-inl.h"
 #include "src/execution/microtask-queue.h"
-#include "src/execution/off-thread-isolate.h"
 #include "src/execution/protectors-inl.h"
 #include "src/heap/factory-inl.h"
 #include "src/heap/heap-inl.h"
@@ -5333,9 +5332,8 @@ void SharedFunctionInfo::DisableOptimization(BailoutReason reason) {
 }
 
 // static
-template <typename Isolate>
 void SharedFunctionInfo::InitFromFunctionLiteral(
-    Isolate* isolate, HandleFor<Isolate, SharedFunctionInfo> shared_info,
+    Isolate* isolate, Handle<SharedFunctionInfo> shared_info,
     FunctionLiteral* lit, bool is_toplevel) {
   DCHECK(!shared_info->name_or_scope_info().IsScopeInfo());
 
@@ -5389,12 +5387,12 @@ void SharedFunctionInfo::InitFromFunctionLiteral(
   shared_info->set_is_safe_to_skip_arguments_adaptor(false);
   shared_info->UpdateExpectedNofPropertiesFromEstimate(lit);
 
-  HandleFor<Isolate, UncompiledData> data;
+  Handle<UncompiledData> data;
 
   ProducedPreparseData* scope_data = lit->produced_preparse_data();
   if (scope_data != nullptr) {
-    HandleFor<Isolate, PreparseData> preparse_data =
-        scope_data->Serialize(isolate);
+    Handle<PreparseData> preparse_data =
+        scope_data->Serialize(shared_info->GetIsolate());
 
     data = isolate->factory()->NewUncompiledDataWithPreparseData(
         lit->GetInferredName(isolate), lit->start_position(),
@@ -5408,16 +5406,6 @@ void SharedFunctionInfo::InitFromFunctionLiteral(
   shared_info->set_uncompiled_data(*data);
 }
 
-template EXPORT_TEMPLATE_DEFINE(V8_EXPORT_PRIVATE) void SharedFunctionInfo::
-    InitFromFunctionLiteral<Isolate>(Isolate* isolate,
-                                     Handle<SharedFunctionInfo> shared_info,
-                                     FunctionLiteral* lit, bool is_toplevel);
-template EXPORT_TEMPLATE_DEFINE(V8_EXPORT_PRIVATE) void SharedFunctionInfo::
-    InitFromFunctionLiteral<OffThreadIsolate>(
-        OffThreadIsolate* isolate,
-        OffThreadHandle<SharedFunctionInfo> shared_info, FunctionLiteral* lit,
-        bool is_toplevel);
-
 uint16_t SharedFunctionInfo::get_property_estimate_from_literal(
     FunctionLiteral* literal) {
   int estimate = literal->expected_property_count();

src/objects/shared-function-info-inl.h

@@ -329,7 +329,7 @@ ScopeInfo SharedFunctionInfo::scope_info() const {
   if (maybe_scope_info.IsScopeInfo()) {
     return ScopeInfo::cast(maybe_scope_info);
   }
-  return GetReadOnlyRoots().empty_scope_info();
+  return ScopeInfo::Empty(GetIsolate());
 }
 
 void SharedFunctionInfo::set_scope_info(ScopeInfo scope_info,
@@ -619,15 +619,7 @@ void SharedFunctionInfo::ClearPreparseData() {
   DCHECK(HasUncompiledDataWithoutPreparseData());
 }
 
-template <typename Isolate>
-void UncompiledData::Init(Isolate* isolate, String inferred_name,
-                          int start_position, int end_position) {
-  set_inferred_name(inferred_name);
-  set_start_position(start_position);
-  set_end_position(end_position);
-}
-
-void UncompiledData::InitAfterBytecodeFlush(
+void UncompiledData::Init(
     String inferred_name, int start_position, int end_position,
     std::function<void(HeapObject object, ObjectSlot slot, HeapObject target)>
         gc_notify_updated_slot) {
@@ -638,14 +630,17 @@ void UncompiledData::InitAfterBytecodeFlush(
   set_end_position(end_position);
 }
 
-template <typename Isolate>
-void UncompiledDataWithPreparseData::Init(Isolate* isolate,
-                                          String inferred_name,
-                                          int start_position, int end_position,
-                                          PreparseData scope_data) {
-  this->UncompiledData::Init(isolate, inferred_name, start_position,
-                             end_position);
+void UncompiledDataWithPreparseData::Init(
+    String inferred_name, int start_position, int end_position,
+    PreparseData scope_data,
+    std::function<void(HeapObject object, ObjectSlot slot, HeapObject target)>
+        gc_notify_updated_slot) {
+  this->UncompiledData::Init(inferred_name, start_position, end_position,
+                             gc_notify_updated_slot);
   set_preparse_data(scope_data);
+  gc_notify_updated_slot(
+      *this, RawField(UncompiledDataWithPreparseData::kPreparseDataOffset),
+      scope_data);
 }
 
 bool SharedFunctionInfo::HasWasmExportedFunctionData() const {

src/objects/shared-function-info.h

@@ -9,7 +9,6 @@
 
 #include "src/base/bit-field.h"
 #include "src/codegen/bailout-reason.h"
-#include "src/handles/handle-for.h"
 #include "src/objects/compressed-slots.h"
 #include "src/objects/function-kind.h"
 #include "src/objects/function-syntax-kind.h"
@@ -100,14 +99,11 @@ class PreparseData
 class UncompiledData
     : public TorqueGeneratedUncompiledData<UncompiledData, HeapObject> {
  public:
-  template <typename Isolate>
-  inline void Init(Isolate* isolate, String inferred_name, int start_position,
-                   int end_position);
-
-  inline void InitAfterBytecodeFlush(
+  inline void Init(
       String inferred_name, int start_position, int end_position,
       std::function<void(HeapObject object, ObjectSlot slot, HeapObject target)>
-          gc_notify_updated_slot);
+          gc_notify_updated_slot =
+              [](HeapObject object, ObjectSlot slot, HeapObject target) {});
 
   using BodyDescriptor =
       FixedBodyDescriptor<kStartOfStrongFieldsOffset, kEndOfStrongFieldsOffset,
@@ -139,9 +135,12 @@ class UncompiledDataWithPreparseData
  public:
   DECL_PRINTER(UncompiledDataWithPreparseData)
 
-  template <typename Isolate>
-  inline void Init(Isolate* isolate, String inferred_name, int start_position,
-                   int end_position, PreparseData scope_data);
+  inline void Init(
+      String inferred_name, int start_position, int end_position,
+      PreparseData scope_data,
+      std::function<void(HeapObject object, ObjectSlot slot, HeapObject target)>
+          gc_notify_updated_slot =
+              [](HeapObject object, ObjectSlot slot, HeapObject target) {});
 
   using BodyDescriptor = SubclassBodyDescriptor<
       UncompiledData::BodyDescriptor,
@@ -554,9 +553,8 @@ class SharedFunctionInfo : public HeapObject {
   inline bool has_simple_parameters();
 
   // Initialize a SharedFunctionInfo from a parsed function literal.
-  template <typename Isolate>
-  static void InitFromFunctionLiteral(
-      Isolate* isolate, HandleFor<Isolate, SharedFunctionInfo> shared_info,
+  static void InitFromFunctionLiteral(Isolate* isolate,
+                                      Handle<SharedFunctionInfo> shared_info,
                                       FunctionLiteral* lit, bool is_toplevel);
 
   // Updates the expected number of properties based on estimate from parser.
@@ -589,7 +587,6 @@ class SharedFunctionInfo : public HeapObject {
   // Dispatched behavior.
   DECL_PRINTER(SharedFunctionInfo)
   DECL_VERIFIER(SharedFunctionInfo)
-  void SharedFunctionInfoVerify(OffThreadIsolate* isolate);
 #ifdef OBJECT_PRINT
   void PrintSourceCode(std::ostream& os);
 #endif
@@ -641,8 +638,6 @@ class SharedFunctionInfo : public HeapObject {
   inline bool needs_home_object() const;
 
  private:
-  void SharedFunctionInfoVerify(ReadOnlyRoots roots);
-
   // [name_or_scope_info]: Function name string, kNoSharedNameSentinel or
   // ScopeInfo.
   DECL_ACCESSORS(name_or_scope_info, Object)
@@ -665,8 +660,7 @@ class SharedFunctionInfo : public HeapObject {
 
   inline uint16_t get_property_estimate_from_literal(FunctionLiteral* literal);
 
-  template <typename Impl>
-  friend class FactoryBase;
+  friend class Factory;
   friend class V8HeapExplorer;
   FRIEND_TEST(PreParserTest, LazyFunctionLength);
 

src/parsing/preparse-data-impl.h

@@ -199,7 +199,6 @@ class ZonePreparseData : public ZoneObject {
                                      int child_length);
 
   Handle<PreparseData> Serialize(Isolate* isolate);
-  OffThreadHandle<PreparseData> Serialize(OffThreadIsolate* isolate);
 
   int children_length() const { return static_cast<int>(children_.size()); }
 

src/parsing/preparse-data.cc

@@ -9,13 +9,11 @@
 #include "src/ast/scopes.h"
 #include "src/ast/variables.h"
 #include "src/handles/handles.h"
-#include "src/heap/off-thread-factory.h"
 #include "src/objects/objects-inl.h"
 #include "src/objects/shared-function-info.h"
 #include "src/parsing/parser.h"
 #include "src/parsing/preparse-data-impl.h"
 #include "src/parsing/preparser.h"
-#include "src/roots/roots.h"
 #include "src/zone/zone-list-inl.h"  // crbug.com/v8/8816
 
 namespace v8 {
@@ -433,17 +431,6 @@ Handle<PreparseData> PreparseDataBuilder::ByteData::CopyToHeap(
   return data;
 }
 
-OffThreadHandle<PreparseData>
-PreparseDataBuilder::ByteData::CopyToOffThreadHeap(OffThreadIsolate* isolate,
-                                                   int children_length) {
-  DCHECK(is_finalized_);
-  int data_length = zone_byte_data_.length();
-  OffThreadHandle<PreparseData> data =
-      isolate->factory()->NewPreparseData(data_length, children_length);
-  data->copy_in(0, zone_byte_data_.begin(), data_length);
-  return data;
-}
-
 Handle<PreparseData> PreparseDataBuilder::Serialize(Isolate* isolate) {
   DCHECK(HasData());
   DCHECK(!ThisOrParentBailedOut());
@@ -460,23 +447,6 @@ Handle<PreparseData> PreparseDataBuilder::Serialize(Isolate* isolate) {
   return data;
 }
 
-OffThreadHandle<PreparseData> PreparseDataBuilder::Serialize(
-    OffThreadIsolate* isolate) {
-  DCHECK(HasData());
-  DCHECK(!ThisOrParentBailedOut());
-  OffThreadHandle<PreparseData> data =
-      byte_data_.CopyToOffThreadHeap(isolate, num_inner_with_data_);
-  int i = 0;
-  DCHECK(finalized_children_);
-  for (const auto& builder : children_) {
-    if (!builder->HasData()) continue;
-    OffThreadHandle<PreparseData> child_data = builder->Serialize(isolate);
-    data->set_child(i++, *child_data);
-  }
-  DCHECK_EQ(i, data->children_length());
-  return data;
-}
-
 ZonePreparseData* PreparseDataBuilder::Serialize(Zone* zone) {
   DCHECK(HasData());
   DCHECK(!ThisOrParentBailedOut());
@@ -503,10 +473,6 @@ class BuilderProducedPreparseData final : public ProducedPreparseData {
     return builder_->Serialize(isolate);
   }
 
-  OffThreadHandle<PreparseData> Serialize(OffThreadIsolate* isolate) final {
-    return builder_->Serialize(isolate);
-  }
-
   ZonePreparseData* Serialize(Zone* zone) final {
     return builder_->Serialize(zone);
   }
@@ -525,11 +491,6 @@ class OnHeapProducedPreparseData final : public ProducedPreparseData {
     return data_;
   }
 
-  OffThreadHandle<PreparseData> Serialize(OffThreadIsolate* isolate) final {
-    // Not required.
-    UNREACHABLE();
-  }
-
   ZonePreparseData* Serialize(Zone* zone) final {
     // Not required.
     UNREACHABLE();
@@ -547,10 +508,6 @@ class ZoneProducedPreparseData final : public ProducedPreparseData {
     return data_->Serialize(isolate);
   }
 
-  OffThreadHandle<PreparseData> Serialize(OffThreadIsolate* isolate) final {
-    return data_->Serialize(isolate);
-  }
-
   ZonePreparseData* Serialize(Zone* zone) final { return data_; }
 
  private:
@@ -793,23 +750,6 @@ Handle<PreparseData> ZonePreparseData::Serialize(Isolate* isolate) {
   return result;
 }
 
-OffThreadHandle<PreparseData> ZonePreparseData::Serialize(
-    OffThreadIsolate* isolate) {
-  int data_size = static_cast<int>(byte_data()->size());
-  int child_data_length = children_length();
-  OffThreadHandle<PreparseData> result =
-      isolate->factory()->NewPreparseData(data_size, child_data_length);
-  result->copy_in(0, byte_data()->data(), data_size);
-
-  for (int i = 0; i < child_data_length; i++) {
-    ZonePreparseData* child = get_child(i);
-    DCHECK_NOT_NULL(child);
-    OffThreadHandle<PreparseData> child_data = child->Serialize(isolate);
-    result->set_child(i, *child_data);
-  }
-  return result;
-}
-
 ZoneConsumedPreparseData::ZoneConsumedPreparseData(Zone* zone,
                                                    ZonePreparseData* data)
     : data_(data), scope_data_wrapper_(data_->byte_data()) {

src/parsing/preparse-data.h

@@ -140,8 +140,6 @@ class V8_EXPORT_PRIVATE PreparseDataBuilder : public ZoneObject,
     void Finalize(Zone* zone);
 
     Handle<PreparseData> CopyToHeap(Isolate* isolate, int children_length);
-    OffThreadHandle<PreparseData> CopyToOffThreadHeap(OffThreadIsolate* isolate,
-                                                      int children_length);
     inline ZonePreparseData* CopyToZone(Zone* zone, int children_length);
 
     void Reserve(size_t bytes);
@@ -210,7 +208,6 @@ class V8_EXPORT_PRIVATE PreparseDataBuilder : public ZoneObject,
   friend class BuilderProducedPreparseData;
 
   Handle<PreparseData> Serialize(Isolate* isolate);
-  OffThreadHandle<PreparseData> Serialize(OffThreadIsolate* isolate);
   ZonePreparseData* Serialize(Zone* zone);
 
   void FinalizeChildren(Zone* zone);
@@ -253,12 +250,6 @@ class ProducedPreparseData : public ZoneObject {
   // MaybeHandle.
   virtual Handle<PreparseData> Serialize(Isolate* isolate) = 0;
 
-  // If there is data (if the Scope contains skippable inner functions), move
-  // the data into the heap and return a Handle to it; otherwise return a null
-  // MaybeHandle.
-  virtual OffThreadHandle<PreparseData> Serialize(
-      OffThreadIsolate* isolate) = 0;
-
   // If there is data (if the Scope contains skippable inner functions), return
   // an off-heap ZonePreparseData representing the data; otherwise
   // return nullptr.

src/parsing/scanner-character-streams.cc

@@ -794,13 +794,8 @@ std::unique_ptr<Utf16CharacterStream> ScannerStream::ForTesting(
     const char* data, size_t length) {
   return std::unique_ptr<Utf16CharacterStream>(
       new BufferedCharacterStream<TestingStream>(
-          0, reinterpret_cast<const uint8_t*>(data), length));
-}
-
-std::unique_ptr<Utf16CharacterStream> ScannerStream::ForTesting(
-    const uint16_t* data, size_t length) {
-  return std::unique_ptr<Utf16CharacterStream>(
-      new UnbufferedCharacterStream<TestingStream>(0, data, length));
+          static_cast<size_t>(0), reinterpret_cast<const uint8_t*>(data),
+          static_cast<size_t>(length)));
 }
 
 Utf16CharacterStream* ScannerStream::For(

src/parsing/scanner-character-streams.h

@@ -31,8 +31,6 @@ class V8_EXPORT_PRIVATE ScannerStream {
   static std::unique_ptr<Utf16CharacterStream> ForTesting(const char* data);
   static std::unique_ptr<Utf16CharacterStream> ForTesting(const char* data,
                                                           size_t length);
-  static std::unique_ptr<Utf16CharacterStream> ForTesting(const uint16_t* data,
-                                                          size_t length);
 };
 
 }  // namespace internal

test/unittests/heap/off-thread-factory-unittest.cc

@@ -8,25 +8,12 @@
 #include <memory>
 
 #include "src/ast/ast-value-factory.h"
-#include "src/ast/ast.h"
-#include "src/ast/scopes.h"
-#include "src/common/assert-scope.h"
-#include "src/common/globals.h"
 #include "src/execution/off-thread-isolate.h"
 #include "src/handles/handles-inl.h"
 #include "src/handles/handles.h"
-#include "src/heap/off-thread-factory-inl.h"
+#include "src/heap/off-thread-factory.h"
 #include "src/objects/fixed-array.h"
-#include "src/objects/script.h"
-#include "src/objects/shared-function-info.h"
 #include "src/objects/string.h"
-#include "src/parsing/parse-info.h"
-#include "src/parsing/parser.h"
-#include "src/parsing/rewriter.h"
-#include "src/parsing/scanner-character-streams.h"
-#include "src/parsing/scanner.h"
-#include "src/strings/unicode-inl.h"
-#include "src/utils/utils.h"
 #include "test/unittests/test-utils.h"
 
 namespace v8 {
@@ -34,74 +21,10 @@ namespace internal {
 
 class OffThreadIsolate;
 
-namespace {
-
-std::vector<uint16_t> DecodeUtf8(const std::string& string) {
-  if (string.empty()) return {};
-
-  auto utf8_data =
-      Vector<const uint8_t>::cast(VectorOf(string.data(), string.length()));
-  Utf8Decoder decoder(utf8_data);
-
-  std::vector<uint16_t> utf16(decoder.utf16_length());
-  decoder.Decode(&utf16[0], utf8_data);
-
-  return utf16;
-}
-
-}  // namespace
-
 class OffThreadFactoryTest : public TestWithIsolateAndZone {
  public:
   OffThreadFactoryTest()
-      : TestWithIsolateAndZone(),
-        off_thread_isolate_(isolate()),
-        parse_info_(isolate()) {}
-
-  FunctionLiteral* ParseProgram(const char* source) {
-    auto utf16_source = DecodeUtf8(source);
-
-    // Normally this would be an external string or whatever, we don't have to
-    // worry about it for now.
-    source_string_ =
-        factory()->NewStringFromUtf8(CStrVector(source)).ToHandleChecked();
-
-    parse_info_.set_character_stream(
-        ScannerStream::ForTesting(utf16_source.data(), utf16_source.size()));
-    parse_info_.set_toplevel();
-    parse_info_.set_allow_lazy_parsing();
-
-    {
-      DisallowHeapAllocation no_allocation;
-      DisallowHandleAllocation no_handles;
-      DisallowHeapAccess no_heap_access;
-
-      Parser parser(parse_info());
-      parser.InitializeEmptyScopeChain(parse_info());
-      parser.ParseOnBackground(parse_info());
-
-      CHECK(DeclarationScope::Analyze(parse_info()));
-    }
-
-    parse_info()->ast_value_factory()->Internalize(off_thread_isolate());
-    DeclarationScope::AllocateScopeInfos(parse_info(), off_thread_isolate());
-
-    script_ = parse_info_.CreateScript(off_thread_isolate(),
-                                       off_thread_factory()->empty_string(),
-                                       ScriptOriginOptions());
-
-    // Create the SFI list on the script so that SFI SetScript works.
-    OffThreadHandle<WeakFixedArray> infos =
-        off_thread_factory()->NewWeakFixedArray(
-            parse_info()->max_function_literal_id() + 1, AllocationType::kOld);
-    script_->set_shared_function_infos(*infos);
-
-    return parse_info()->literal();
-  }
-
-  ParseInfo* parse_info() { return &parse_info_; }
-
-  OffThreadHandle<Script> script() { return script_; }
+      : TestWithIsolateAndZone(), off_thread_isolate_(isolate()) {}
 
   OffThreadIsolate* off_thread_isolate() { return &off_thread_isolate_; }
   OffThreadFactory* off_thread_factory() {
@@ -118,9 +41,6 @@ class OffThreadFactoryTest : public TestWithIsolateAndZone {
 
  private:
   OffThreadIsolate off_thread_isolate_;
-  ParseInfo parse_info_;
-  Handle<String> source_string_;
-  OffThreadHandle<Script> script_;
 };
 
 TEST_F(OffThreadFactoryTest, HandleOrOffThreadHandle_IsNullWhenConstructed) {
@@ -253,95 +173,5 @@ TEST_F(OffThreadFactoryTest, AstConsString_CreatesConsString) {
       "foobar-plus-padding-for-length")));
 }
 
-TEST_F(OffThreadFactoryTest, EmptyScript) {
-  FunctionLiteral* program = ParseProgram("");
-
-  SharedFunctionInfo shared =
-      *off_thread_factory()->NewSharedFunctionInfoForLiteral(program, script(),
-                                                             true);
-
-  off_thread_factory()->FinishOffThread();
-
-  Handle<SharedFunctionInfo> root_sfi = handle(shared, isolate());
-  off_thread_factory()->Publish(isolate());
-
-  EXPECT_EQ(root_sfi->function_literal_id(), 0);
-}
-
-TEST_F(OffThreadFactoryTest, LazyFunction) {
-  FunctionLiteral* program = ParseProgram("function lazy() {}");
-  FunctionLiteral* lazy = program->scope()
-                              ->declarations()
-                              ->AtForTest(0)
-                              ->AsFunctionDeclaration()
-                              ->fun();
-
-  SharedFunctionInfo shared =
-      *off_thread_factory()->NewSharedFunctionInfoForLiteral(lazy, script(),
-                                                             true);
-
-  off_thread_factory()->FinishOffThread();
-
-  Handle<SharedFunctionInfo> lazy_sfi = handle(shared, isolate());
-  off_thread_factory()->Publish(isolate());
-
-  EXPECT_EQ(lazy_sfi->function_literal_id(), 1);
-  EXPECT_TRUE(lazy_sfi->Name().IsOneByteEqualTo(CStrVector("lazy")));
-  EXPECT_FALSE(lazy_sfi->is_compiled());
-  EXPECT_TRUE(lazy_sfi->HasUncompiledDataWithoutPreparseData());
-}
-
-TEST_F(OffThreadFactoryTest, EagerFunction) {
-  FunctionLiteral* program = ParseProgram("(function eager() {})");
-  FunctionLiteral* eager = program->body()
-                               ->at(0)
-                               ->AsExpressionStatement()
-                               ->expression()
-                               ->AsFunctionLiteral();
-
-  SharedFunctionInfo shared =
-      *off_thread_factory()->NewSharedFunctionInfoForLiteral(eager, script(),
-                                                             true);
-
-  off_thread_factory()->FinishOffThread();
-
-  Handle<SharedFunctionInfo> eager_sfi = handle(shared, isolate());
-  off_thread_factory()->Publish(isolate());
-
-  EXPECT_EQ(eager_sfi->function_literal_id(), 1);
-  EXPECT_TRUE(eager_sfi->Name().IsOneByteEqualTo(CStrVector("eager")));
-  EXPECT_FALSE(eager_sfi->HasUncompiledData());
-  // TODO(leszeks): Allocate bytecode and enable these checks.
-  // EXPECT_TRUE(eager_sfi->is_compiled());
-  // EXPECT_TRUE(eager_sfi->HasBytecodeArray());
-}
-
-TEST_F(OffThreadFactoryTest, ImplicitNameFunction) {
-  FunctionLiteral* program = ParseProgram("let implicit_name = function() {}");
-  FunctionLiteral* implicit_name = program->body()
-                                       ->at(0)
-                                       ->AsBlock()
-                                       ->statements()
-                                       ->at(0)
-                                       ->AsExpressionStatement()
-                                       ->expression()
-                                       ->AsAssignment()
-                                       ->value()
-                                       ->AsFunctionLiteral();
-
-  SharedFunctionInfo shared =
-      *off_thread_factory()->NewSharedFunctionInfoForLiteral(implicit_name,
-                                                             script(), true);
-
-  off_thread_factory()->FinishOffThread();
-
-  Handle<SharedFunctionInfo> implicit_name_sfi = handle(shared, isolate());
-  off_thread_factory()->Publish(isolate());
-
-  EXPECT_EQ(implicit_name_sfi->function_literal_id(), 1);
-  EXPECT_TRUE(
-      implicit_name_sfi->Name().IsOneByteEqualTo(CStrVector("implicit_name")));
-}
-
 }  // namespace internal
 }  // namespace v8