[builtins] For-in fast path for empty dict receivers

Change-Id: I58fc4ad8104f9a334a24de181168122f215a0505

BUG=chromium:678427

Change-Id: I58fc4ad8104f9a334a24de181168122f215a0505
Reviewed-on: https://chromium-review.googlesource.com/447980Reviewed-by: Mythri Alle <mythria@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43628}

BUILD.gn

@@ -992,6 +992,8 @@ v8_source_set("v8_base") {
     "src/builtins/builtins-date.cc",
     "src/builtins/builtins-debug.cc",
     "src/builtins/builtins-error.cc",
+    "src/builtins/builtins-forin.cc",
+    "src/builtins/builtins-forin.h",
     "src/builtins/builtins-function.cc",
     "src/builtins/builtins-generator.cc",
     "src/builtins/builtins-global.cc",
@@ -1003,7 +1005,6 @@ v8_source_set("v8_base") {
     "src/builtins/builtins-math.cc",
     "src/builtins/builtins-number.cc",
     "src/builtins/builtins-object.cc",
-    "src/builtins/builtins-object.h",
     "src/builtins/builtins-promise.cc",
     "src/builtins/builtins-promise.h",
     "src/builtins/builtins-proxy.cc",

src/builtins/builtins-forin.cc

+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/builtins/builtins-forin.h"
+
+#include "src/builtins/builtins-utils.h"
+#include "src/builtins/builtins.h"
+#include "src/code-factory.h"
+#include "src/code-stub-assembler.h"
+#include "src/counters.h"
+#include "src/keys.h"
+#include "src/lookup.h"
+#include "src/objects-inl.h"
+#include "src/property-descriptor.h"
+
+namespace v8 {
+namespace internal {
+
+typedef compiler::Node Node;
+
+Node* ForInBuiltinsAssembler::ForInFilter(Node* key, Node* object,
+                                          Node* context) {
+  Label return_undefined(this, Label::kDeferred), return_to_name(this),
+      end(this);
+
+  Variable var_result(this, MachineRepresentation::kTagged);
+
+  Node* has_property =
+      HasProperty(object, key, context, Runtime::kForInHasProperty);
+
+  Branch(WordEqual(has_property, BooleanConstant(true)), &return_to_name,
+         &return_undefined);
+
+  Bind(&return_to_name);
+  {
+    var_result.Bind(ToName(context, key));
+    Goto(&end);
+  }
+
+  Bind(&return_undefined);
+  {
+    var_result.Bind(UndefinedConstant());
+    Goto(&end);
+  }
+
+  Bind(&end);
+  return var_result.value();
+}
+
+std::tuple<Node*, Node*, Node*> ForInBuiltinsAssembler::EmitForInPrepare(
+    Node* object, Node* context, Label* call_runtime,
+    Label* nothing_to_iterate) {
+  Label use_cache(this);
+  CSA_ASSERT(this, IsJSReceiver(object));
+
+  CheckEnumCache(object, &use_cache, nothing_to_iterate, call_runtime);
+
+  Bind(&use_cache);
+  Node* map = LoadMap(object);
+  Node* enum_length = EnumLength(map);
+  GotoIf(WordEqual(enum_length, SmiConstant(0)), nothing_to_iterate);
+  Node* descriptors = LoadMapDescriptors(map);
+  Node* cache_offset =
+      LoadObjectField(descriptors, DescriptorArray::kEnumCacheOffset);
+  Node* enum_cache = LoadObjectField(
+      cache_offset, DescriptorArray::kEnumCacheBridgeCacheOffset);
+
+  return std::make_tuple(map, enum_cache, enum_length);
+}
+
+Node* ForInBuiltinsAssembler::EnumLength(Node* map) {
+  CSA_ASSERT(this, IsMap(map));
+  Node* bitfield_3 = LoadMapBitField3(map);
+  Node* enum_length = DecodeWordFromWord32<Map::EnumLengthBits>(bitfield_3);
+  return SmiTag(enum_length);
+}
+
+void ForInBuiltinsAssembler::CheckPrototypeEnumCache(Node* receiver, Node* map,
+                                                     Label* use_cache,
+                                                     Label* use_runtime) {
+  Variable current_js_object(this, MachineRepresentation::kTagged, receiver);
+  Variable current_map(this, MachineRepresentation::kTagged, map);
+
+  // These variables are updated in the loop below.
+  Variable* loop_vars[2] = {&current_js_object, &current_map};
+  Label loop(this, 2, loop_vars), next(this);
+
+  Goto(&loop);
+  // Check that there are no elements. |current_js_object| contains
+  // the current JS object we've reached through the prototype chain.
+  Bind(&loop);
+  {
+    Label if_elements(this), if_no_elements(this);
+    Node* elements = LoadElements(current_js_object.value());
+    Node* empty_fixed_array = LoadRoot(Heap::kEmptyFixedArrayRootIndex);
+    // Check that there are no elements.
+    Branch(WordEqual(elements, empty_fixed_array), &if_no_elements,
+           &if_elements);
+    Bind(&if_elements);
+    {
+      // Second chance, the object may be using the empty slow element
+      // dictionary.
+      Node* slow_empty_dictionary =
+          LoadRoot(Heap::kEmptySlowElementDictionaryRootIndex);
+      Branch(WordNotEqual(elements, slow_empty_dictionary), use_runtime,
+             &if_no_elements);
+    }
+
+    Bind(&if_no_elements);
+    {
+      // Update map prototype.
+      current_js_object.Bind(LoadMapPrototype(current_map.value()));
+      Branch(WordEqual(current_js_object.value(), NullConstant()), use_cache,
+             &next);
+    }
+  }
+
+  Bind(&next);
+  {
+    // For all objects but the receiver, check that the cache is empty.
+    current_map.Bind(LoadMap(current_js_object.value()));
+    Node* enum_length = EnumLength(current_map.value());
+    Node* zero_constant = SmiConstant(Smi::kZero);
+    Branch(WordEqual(enum_length, zero_constant), &loop, use_runtime);
+  }
+}
+
+void ForInBuiltinsAssembler::CheckEnumCache(Node* receiver, Label* use_cache,
+                                            Label* nothing_to_iterate,
+                                            Label* use_runtime) {
+  Node* map = LoadMap(receiver);
+
+  Label check_empty_prototype(this),
+      check_dict_receiver(this, Label::kDeferred);
+
+  // Check if the enum length field is properly initialized, indicating that
+  // there is an enum cache.
+  {
+    Node* invalid_enum_cache_sentinel =
+        SmiConstant(Smi::FromInt(kInvalidEnumCacheSentinel));
+    Node* enum_length = EnumLength(map);
+    Branch(WordEqual(enum_length, invalid_enum_cache_sentinel),
+           &check_dict_receiver, &check_empty_prototype);
+  }
+
+  // Check that there are no elements on the fast |receiver| and its prototype
+  // chain.
+  Bind(&check_empty_prototype);
+  CheckPrototypeEnumCache(receiver, map, use_cache, use_runtime);
+
+  Label dict_loop(this);
+  Bind(&check_dict_receiver);
+  {
+    // Avoid runtime-call for empty dictionary receivers.
+    GotoIfNot(IsDictionaryMap(map), use_runtime);
+    Node* properties = LoadProperties(receiver);
+    Node* length = LoadFixedArrayElement(
+        properties, NameDictionary::kNumberOfElementsIndex);
+    GotoIfNot(WordEqual(length, SmiConstant(0)), use_runtime);
+    // Check that there are no elements on the |receiver| and its prototype
+    // chain. Given that we do not create an EnumCache for dict-mode objects,
+    // directly jump to |nothing_to_iterate| if there are no elements and no
+    // properties on the |receiver|.
+    CheckPrototypeEnumCache(receiver, map, nothing_to_iterate, use_runtime);
+  }
+}
+
+TF_BUILTIN(ForInFilter, ForInBuiltinsAssembler) {
+  typedef ForInFilterDescriptor Descriptor;
+
+  Node* key = Parameter(Descriptor::kKey);
+  Node* object = Parameter(Descriptor::kObject);
+  Node* context = Parameter(Descriptor::kContext);
+
+  Return(ForInFilter(key, object, context));
+}
+
+TF_BUILTIN(ForInNext, ForInBuiltinsAssembler) {
+  typedef ForInNextDescriptor Descriptor;
+
+  Label filter(this);
+  Node* object = Parameter(Descriptor::kObject);
+  Node* cache_array = Parameter(Descriptor::kCacheArray);
+  Node* cache_type = Parameter(Descriptor::kCacheType);
+  Node* index = Parameter(Descriptor::kIndex);
+  Node* context = Parameter(Descriptor::kContext);
+
+  Node* key = LoadFixedArrayElement(cache_array, SmiUntag(index));
+  Node* map = LoadMap(object);
+  GotoIfNot(WordEqual(map, cache_type), &filter);
+  Return(key);
+  Bind(&filter);
+  Return(ForInFilter(key, object, context));
+}
+
+TF_BUILTIN(ForInPrepare, ForInBuiltinsAssembler) {
+  typedef ForInPrepareDescriptor Descriptor;
+
+  Label call_runtime(this), nothing_to_iterate(this);
+  Node* object = Parameter(Descriptor::kObject);
+  Node* context = Parameter(Descriptor::kContext);
+
+  Node* cache_type;
+  Node* cache_array;
+  Node* cache_length;
+  std::tie(cache_type, cache_array, cache_length) =
+      EmitForInPrepare(object, context, &call_runtime, &nothing_to_iterate);
+
+  Return(cache_type, cache_array, cache_length);
+
+  Bind(&call_runtime);
+  TailCallRuntime(Runtime::kForInPrepare, context, object);
+
+  Bind(&nothing_to_iterate);
+  {
+    Node* zero = SmiConstant(0);
+    Return(zero, zero, zero);
+  }
+}
+}  // namespace internal
+}  // namespace v8

src/builtins/builtins-object.h → src/builtins/builtins-forin.h

@@ -8,18 +8,26 @@
 namespace v8 {
 namespace internal {
 
-class ObjectBuiltinsAssembler : public CodeStubAssembler {
+class ForInBuiltinsAssembler : public CodeStubAssembler {
  public:
-  explicit ObjectBuiltinsAssembler(compiler::CodeAssemblerState* state)
+  explicit ForInBuiltinsAssembler(compiler::CodeAssemblerState* state)
       : CodeStubAssembler(state) {}
 
   std::tuple<Node*, Node*, Node*> EmitForInPrepare(Node* object, Node* context,
                                                    Label* call_runtime,
                                                    Label* nothing_to_iterate);
 
- protected:
-  void IsString(Node* object, Label* if_string, Label* if_notstring);
-  void ReturnToStringFormat(Node* context, Node* string);
+  Node* ForInFilter(Node* key, Node* object, Node* context);
+
+ private:
+  // Get the enumerable length from |map| and return the result as a Smi.
+  Node* EnumLength(Node* map);
+  void CheckPrototypeEnumCache(Node* receiver, Node* map, Label* use_cache,
+                               Label* use_runtime);
+  // Check the cache validity for |receiver|. Branch to |use_cache| if
+  // the cache is valid, otherwise branch to |use_runtime|.
+  void CheckEnumCache(Node* receiver, Label* use_cache,
+                      Label* nothing_to_iterate, Label* use_runtime);
 };
 
 }  // namespace internal

src/builtins/builtins-object.cc

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "src/builtins/builtins-object.h"
 #include "src/builtins/builtins-utils.h"
 #include "src/builtins/builtins.h"
 #include "src/code-factory.h"
@@ -18,25 +17,41 @@ namespace internal {
 
 typedef compiler::Node Node;
 
-std::tuple<Node*, Node*, Node*> ObjectBuiltinsAssembler::EmitForInPrepare(
-    Node* object, Node* context, Label* call_runtime,
-    Label* nothing_to_iterate) {
-  Label use_cache(this);
-  CSA_ASSERT(this, IsJSReceiver(object));
+class ObjectBuiltinsAssembler : public CodeStubAssembler {
+ public:
+  explicit ObjectBuiltinsAssembler(compiler::CodeAssemblerState* state)
+      : CodeStubAssembler(state) {}
 
-  CheckEnumCache(object, &use_cache, call_runtime);
-  Bind(&use_cache);
-  Node* map = LoadMap(object);
-  Node* enum_length = EnumLength(map);
-  GotoIf(WordEqual(enum_length, SmiConstant(0)), nothing_to_iterate);
-  Node* descriptors = LoadMapDescriptors(map);
-  Node* cache_offset =
-      LoadObjectField(descriptors, DescriptorArray::kEnumCacheOffset);
-  Node* enum_cache = LoadObjectField(
-      cache_offset, DescriptorArray::kEnumCacheBridgeCacheOffset);
+ protected:
+  void IsString(Node* object, Label* if_string, Label* if_notstring);
+  void ReturnToStringFormat(Node* context, Node* string);
+};
+
+void ObjectBuiltinsAssembler::IsString(Node* object, Label* if_string,
+                                       Label* if_notstring) {
+  Label if_notsmi(this);
+  Branch(TaggedIsSmi(object), if_notstring, &if_notsmi);
+
+  Bind(&if_notsmi);
+  {
+    Node* instance_type = LoadInstanceType(object);
+
+    Branch(IsStringInstanceType(instance_type), if_string, if_notstring);
+  }
+}
+
+void ObjectBuiltinsAssembler::ReturnToStringFormat(Node* context,
+                                                   Node* string) {
+  Node* lhs = HeapConstant(factory()->NewStringFromStaticChars("[object "));
+  Node* rhs = HeapConstant(factory()->NewStringFromStaticChars("]"));
 
-  return std::make_tuple(map, enum_cache, enum_length);
+  Callable callable =
+      CodeFactory::StringAdd(isolate(), STRING_ADD_CHECK_NONE, NOT_TENURED);
+
+  Return(CallStub(callable, context, CallStub(callable, context, lhs, string),
+                  rhs));
 }
+
 // -----------------------------------------------------------------------------
 // ES6 section 19.1 Object Objects
 
@@ -122,31 +137,6 @@ BUILTIN(ObjectPrototypePropertyIsEnumerable) {
   return isolate->heap()->ToBoolean((maybe.FromJust() & DONT_ENUM) == 0);
 }
 
-void ObjectBuiltinsAssembler::IsString(Node* object, Label* if_string,
-                                       Label* if_notstring) {
-  Label if_notsmi(this);
-  Branch(TaggedIsSmi(object), if_notstring, &if_notsmi);
-
-  Bind(&if_notsmi);
-  {
-    Node* instance_type = LoadInstanceType(object);
-
-    Branch(IsStringInstanceType(instance_type), if_string, if_notstring);
-  }
-}
-
-void ObjectBuiltinsAssembler::ReturnToStringFormat(Node* context,
-                                                   Node* string) {
-  Node* lhs = HeapConstant(factory()->NewStringFromStaticChars("[object "));
-  Node* rhs = HeapConstant(factory()->NewStringFromStaticChars("]"));
-
-  Callable callable =
-      CodeFactory::StringAdd(isolate(), STRING_ADD_CHECK_NONE, NOT_TENURED);
-
-  Return(CallStub(callable, context, CallStub(callable, context, lhs, string),
-                  rhs));
-}
-
 // ES6 section 19.1.3.6 Object.prototype.toString
 TF_BUILTIN(ObjectProtoToString, ObjectBuiltinsAssembler) {
   Label return_undefined(this, Label::kDeferred),
@@ -927,59 +917,6 @@ TF_BUILTIN(HasProperty, ObjectBuiltinsAssembler) {
   Return(HasProperty(object, key, context, Runtime::kHasProperty));
 }
 
-TF_BUILTIN(ForInFilter, ObjectBuiltinsAssembler) {
-  typedef ForInFilterDescriptor Descriptor;
-
-  Node* key = Parameter(Descriptor::kKey);
-  Node* object = Parameter(Descriptor::kObject);
-  Node* context = Parameter(Descriptor::kContext);
-
-  Return(ForInFilter(key, object, context));
-}
-
-TF_BUILTIN(ForInNext, ObjectBuiltinsAssembler) {
-  typedef ForInNextDescriptor Descriptor;
-
-  Label filter(this);
-  Node* object = Parameter(Descriptor::kObject);
-  Node* cache_array = Parameter(Descriptor::kCacheArray);
-  Node* cache_type = Parameter(Descriptor::kCacheType);
-  Node* index = Parameter(Descriptor::kIndex);
-  Node* context = Parameter(Descriptor::kContext);
-
-  Node* key = LoadFixedArrayElement(cache_array, SmiUntag(index));
-  Node* map = LoadMap(object);
-  GotoIfNot(WordEqual(map, cache_type), &filter);
-  Return(key);
-  Bind(&filter);
-  Return(ForInFilter(key, object, context));
-}
-
-TF_BUILTIN(ForInPrepare, ObjectBuiltinsAssembler) {
-  typedef ForInPrepareDescriptor Descriptor;
-
-  Label call_runtime(this), nothing_to_iterate(this);
-  Node* object = Parameter(Descriptor::kObject);
-  Node* context = Parameter(Descriptor::kContext);
-
-  Node* cache_type;
-  Node* cache_array;
-  Node* cache_length;
-  std::tie(cache_type, cache_array, cache_length) =
-      EmitForInPrepare(object, context, &call_runtime, &nothing_to_iterate);
-
-  Return(cache_type, cache_array, cache_length);
-
-  Bind(&call_runtime);
-  TailCallRuntime(Runtime::kForInPrepare, context, object);
-
-  Bind(&nothing_to_iterate);
-  {
-    Node* zero = SmiConstant(0);
-    Return(zero, zero, zero);
-  }
-}
-
 TF_BUILTIN(InstanceOf, ObjectBuiltinsAssembler) {
   typedef CompareDescriptor Descriptor;
 

src/code-stub-assembler.cc

@@ -6158,73 +6158,6 @@ Node* CodeStubAssembler::PageFromAddress(Node* address) {
   return WordAnd(address, IntPtrConstant(~Page::kPageAlignmentMask));
 }
 
-Node* CodeStubAssembler::EnumLength(Node* map) {
-  CSA_ASSERT(this, IsMap(map));
-  Node* bitfield_3 = LoadMapBitField3(map);
-  Node* enum_length = DecodeWordFromWord32<Map::EnumLengthBits>(bitfield_3);
-  return SmiTag(enum_length);
-}
-
-void CodeStubAssembler::CheckEnumCache(Node* receiver, Label* use_cache,
-                                       Label* use_runtime) {
-  Variable current_js_object(this, MachineRepresentation::kTagged, receiver);
-
-  Variable current_map(this, MachineRepresentation::kTagged,
-                       LoadMap(current_js_object.value()));
-
-  // These variables are updated in the loop below.
-  Variable* loop_vars[2] = {&current_js_object, &current_map};
-  Label loop(this, 2, loop_vars), next(this);
-
-  // Check if the enum length field is properly initialized, indicating that
-  // there is an enum cache.
-  {
-    Node* invalid_enum_cache_sentinel =
-        SmiConstant(Smi::FromInt(kInvalidEnumCacheSentinel));
-    Node* enum_length = EnumLength(current_map.value());
-    Branch(WordEqual(enum_length, invalid_enum_cache_sentinel), use_runtime,
-           &loop);
-  }
-
-  // Check that there are no elements. |current_js_object| contains
-  // the current JS object we've reached through the prototype chain.
-  Bind(&loop);
-  {
-    Label if_elements(this), if_no_elements(this);
-    Node* elements = LoadElements(current_js_object.value());
-    Node* empty_fixed_array = LoadRoot(Heap::kEmptyFixedArrayRootIndex);
-    // Check that there are no elements.
-    Branch(WordEqual(elements, empty_fixed_array), &if_no_elements,
-           &if_elements);
-    Bind(&if_elements);
-    {
-      // Second chance, the object may be using the empty slow element
-      // dictionary.
-      Node* slow_empty_dictionary =
-          LoadRoot(Heap::kEmptySlowElementDictionaryRootIndex);
-      Branch(WordNotEqual(elements, slow_empty_dictionary), use_runtime,
-             &if_no_elements);
-    }
-
-    Bind(&if_no_elements);
-    {
-      // Update map prototype.
-      current_js_object.Bind(LoadMapPrototype(current_map.value()));
-      Branch(WordEqual(current_js_object.value(), NullConstant()), use_cache,
-             &next);
-    }
-  }
-
-  Bind(&next);
-  {
-    // For all objects but the receiver, check that the cache is empty.
-    current_map.Bind(LoadMap(current_js_object.value()));
-    Node* enum_length = EnumLength(current_map.value());
-    Node* zero_constant = SmiConstant(Smi::kZero);
-    Branch(WordEqual(enum_length, zero_constant), &loop, use_runtime);
-  }
-}
-
 Node* CodeStubAssembler::CreateAllocationSiteInFeedbackVector(
     Node* feedback_vector, Node* slot) {
   Node* size = IntPtrConstant(AllocationSite::kSize);
@@ -7625,34 +7558,6 @@ Node* CodeStubAssembler::SameValue(Node* lhs, Node* rhs, Node* context) {
   return var_result.value();
 }
 
-Node* CodeStubAssembler::ForInFilter(Node* key, Node* object, Node* context) {
-  Label return_undefined(this, Label::kDeferred), return_to_name(this),
-      end(this);
-
-  Variable var_result(this, MachineRepresentation::kTagged);
-
-  Node* has_property =
-      HasProperty(object, key, context, Runtime::kForInHasProperty);
-
-  Branch(WordEqual(has_property, BooleanConstant(true)), &return_to_name,
-         &return_undefined);
-
-  Bind(&return_to_name);
-  {
-    var_result.Bind(ToName(context, key));
-    Goto(&end);
-  }
-
-  Bind(&return_undefined);
-  {
-    var_result.Bind(UndefinedConstant());
-    Goto(&end);
-  }
-
-  Bind(&end);
-  return var_result.value();
-}
-
 Node* CodeStubAssembler::HasProperty(
     Node* object, Node* key, Node* context,
     Runtime::FunctionId fallback_runtime_function_id) {

src/code-stub-assembler.h

@@ -1120,14 +1120,6 @@ class V8_EXPORT_PRIVATE CodeStubAssembler : public compiler::CodeAssembler {
 
   Node* PageFromAddress(Node* address);
 
-  // Get the enumerable length from |map| and return the result as a Smi.
-  Node* EnumLength(Node* map);
-
-  // Check the cache validity for |receiver|. Branch to |use_cache| if
-  // the cache is valid, otherwise branch to |use_runtime|.
-  void CheckEnumCache(Node* receiver, CodeStubAssembler::Label* use_cache,
-                      CodeStubAssembler::Label* use_runtime);
-
   // Create a new weak cell with a specified value and install it into a
   // feedback vector.
   Node* CreateWeakCellInFeedbackVector(Node* feedback_vector, Node* slot,
@@ -1223,7 +1215,6 @@ class V8_EXPORT_PRIVATE CodeStubAssembler : public compiler::CodeAssembler {
   Node* HasProperty(
       Node* object, Node* key, Node* context,
       Runtime::FunctionId fallback_runtime_function_id = Runtime::kHasProperty);
-  Node* ForInFilter(Node* key, Node* object, Node* context);
 
   Node* ClassOf(Node* object);
 

src/interpreter/interpreter.cc

@@ -10,7 +10,7 @@
 #include "src/ast/prettyprinter.h"
 #include "src/builtins/builtins-arguments.h"
 #include "src/builtins/builtins-constructor.h"
-#include "src/builtins/builtins-object.h"
+#include "src/builtins/builtins-forin.h"
 #include "src/code-factory.h"
 #include "src/compilation-info.h"
 #include "src/compiler.h"
@@ -3167,10 +3167,10 @@ void Interpreter::DoForInPrepare(InterpreterAssembler* assembler) {
   Label call_runtime(assembler, Label::kDeferred),
       nothing_to_iterate(assembler, Label::kDeferred);
 
-  ObjectBuiltinsAssembler object_assembler(assembler->state());
+  ForInBuiltinsAssembler forin_assembler(assembler->state());
   std::tie(cache_type, cache_array, cache_length) =
-      object_assembler.EmitForInPrepare(receiver, context, &call_runtime,
-                                        &nothing_to_iterate);
+      forin_assembler.EmitForInPrepare(receiver, context, &call_runtime,
+                                       &nothing_to_iterate);
 
   BuildForInPrepareResult(output_register, cache_type, cache_array,
                           cache_length, assembler);

src/v8.gyp

@@ -494,6 +494,8 @@
         'builtins/builtins-date.cc',
         'builtins/builtins-debug.cc',
         'builtins/builtins-error.cc',
+        'builtins/builtins-forin.cc',
+        'builtins/builtins-forin.h',
         'builtins/builtins-function.cc',
         'builtins/builtins-generator.cc',
         'builtins/builtins-global.cc',
@@ -505,7 +507,6 @@
         'builtins/builtins-math.cc',
         'builtins/builtins-number.cc',
         'builtins/builtins-object.cc',
-        'builtins/builtins-object.h',
         'builtins/builtins-promise.cc',
         'builtins/builtins-promise.h',
         'builtins/builtins-proxy.cc',