[builtins] move builtin files to src/builtins/.

src/builtins.cc

Index: src/builtins.cc
diff --git a/src/builtins.cc b/src/builtins.cc
deleted file mode 100644
index 8be2870449aaee58a6c5229fbe434da5be7afbef..0000000000000000000000000000000000000000
--- a/src/builtins.cc
+++ /dev/null
@@ -1,6804 +0,0 @@
-// Copyright 2012 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.h"
-
-#include "src/api-arguments.h"
-#include "src/api-natives.h"
-#include "src/api.h"
-#include "src/base/ieee754.h"
-#include "src/base/once.h"
-#include "src/bootstrapper.h"
-#include "src/code-factory.h"
-#include "src/code-stub-assembler.h"
-#include "src/dateparser-inl.h"
-#include "src/elements.h"
-#include "src/frames-inl.h"
-#include "src/gdb-jit.h"
-#include "src/globals.h"
-#include "src/ic/handler-compiler.h"
-#include "src/ic/ic.h"
-#include "src/isolate-inl.h"
-#include "src/json-parser.h"
-#include "src/json-stringifier.h"
-#include "src/messages.h"
-#include "src/property-descriptor.h"
-#include "src/prototype.h"
-#include "src/string-builder.h"
-#include "src/uri.h"
-#include "src/vm-state-inl.h"
-
-namespace v8 {
-namespace internal {
-
-namespace {
-
-// Arguments object passed to C++ builtins.
-class BuiltinArguments : public Arguments {
- public:
-  BuiltinArguments(int length, Object** arguments)
-      : Arguments(length, arguments) {
-    // Check we have at least the receiver.
-    DCHECK_LE(1, this->length());
-  }
-
-  Object*& operator[] (int index) {
-    DCHECK_LT(index, length());
-    return Arguments::operator[](index);
-  }
-
-  template <class S> Handle<S> at(int index) {
-    DCHECK_LT(index, length());
-    return Arguments::at<S>(index);
-  }
-
-  Handle<Object> atOrUndefined(Isolate* isolate, int index) {
-    if (index >= length()) {
-      return isolate->factory()->undefined_value();
-    }
-    return at<Object>(index);
-  }
-
-  Handle<Object> receiver() {
-    return Arguments::at<Object>(0);
-  }
-
-  static const int kNewTargetOffset = 0;
-  static const int kTargetOffset = 1;
-  static const int kArgcOffset = 2;
-  static const int kNumExtraArgs = 3;
-  static const int kNumExtraArgsWithReceiver = 4;
-
-  template <class S>
-  Handle<S> target() {
-    return Arguments::at<S>(Arguments::length() - 1 - kTargetOffset);
-  }
-  Handle<HeapObject> new_target() {
-    return Arguments::at<HeapObject>(Arguments::length() - 1 -
-                                     kNewTargetOffset);
-  }
-
-  // Gets the total number of arguments including the receiver (but
-  // excluding extra arguments).
-  int length() const { return Arguments::length() - kNumExtraArgs; }
-};
-
-
-// ----------------------------------------------------------------------------
-// Support macro for defining builtins in C++.
-// ----------------------------------------------------------------------------
-//
-// A builtin function is defined by writing:
-//
-//   BUILTIN(name) {
-//     ...
-//   }
-//
-// In the body of the builtin function the arguments can be accessed
-// through the BuiltinArguments object args.
-// TODO(cbruni): add global flag to check whether any tracing events have been
-// enabled.
-#define BUILTIN(name)                                                        \
-  MUST_USE_RESULT static Object* Builtin_Impl_##name(BuiltinArguments args,  \
-                                                     Isolate* isolate);      \
-                                                                             \
-  V8_NOINLINE static Object* Builtin_Impl_Stats_##name(                      \
-      int args_length, Object** args_object, Isolate* isolate) {             \
-    BuiltinArguments args(args_length, args_object);                         \
-    RuntimeCallTimerScope timer(isolate, &RuntimeCallStats::Builtin_##name); \
-    TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.runtime"),                    \
-                 "V8.Builtin_" #name);                                       \
-    return Builtin_Impl_##name(args, isolate);                               \
-  }                                                                          \
-                                                                             \
-  MUST_USE_RESULT static Object* Builtin_##name(                             \
-      int args_length, Object** args_object, Isolate* isolate) {             \
-    if (FLAG_runtime_call_stats) {                                           \
-      return Builtin_Impl_Stats_##name(args_length, args_object, isolate);   \
-    }                                                                        \
-    BuiltinArguments args(args_length, args_object);                         \
-    return Builtin_Impl_##name(args, isolate);                               \
-  }                                                                          \
-                                                                             \
-  MUST_USE_RESULT static Object* Builtin_Impl_##name(BuiltinArguments args,  \
-                                                     Isolate* isolate)
-
-// ----------------------------------------------------------------------------
-
-#define CHECK_RECEIVER(Type, name, method)                                  \
-  if (!args.receiver()->Is##Type()) {                                       \
-    THROW_NEW_ERROR_RETURN_FAILURE(                                         \
-        isolate,                                                            \
-        NewTypeError(MessageTemplate::kIncompatibleMethodReceiver,          \
-                     isolate->factory()->NewStringFromAsciiChecked(method), \
-                     args.receiver()));                                     \
-  }                                                                         \
-  Handle<Type> name = Handle<Type>::cast(args.receiver())
-
-// Throws a TypeError for {method} if the receiver is not coercible to Object,
-// or converts the receiver to a String otherwise and assigns it to a new var
-// with the given {name}.
-#define TO_THIS_STRING(name, method)                                          \
-  if (args.receiver()->IsNull(isolate) ||                                     \
-      args.receiver()->IsUndefined(isolate)) {                                \
-    THROW_NEW_ERROR_RETURN_FAILURE(                                           \
-        isolate,                                                              \
-        NewTypeError(MessageTemplate::kCalledOnNullOrUndefined,               \
-                     isolate->factory()->NewStringFromAsciiChecked(method))); \
-  }                                                                           \
-  Handle<String> name;                                                        \
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(                                         \
-      isolate, name, Object::ToString(isolate, args.receiver()))
-
-inline bool ClampedToInteger(Isolate* isolate, Object* object, int* out) {
-  // This is an extended version of ECMA-262 7.1.11 handling signed values
-  // Try to convert object to a number and clamp values to [kMinInt, kMaxInt]
-  if (object->IsSmi()) {
-    *out = Smi::cast(object)->value();
-    return true;
-  } else if (object->IsHeapNumber()) {
-    double value = HeapNumber::cast(object)->value();
-    if (std::isnan(value)) {
-      *out = 0;
-    } else if (value > kMaxInt) {
-      *out = kMaxInt;
-    } else if (value < kMinInt) {
-      *out = kMinInt;
-    } else {
-      *out = static_cast<int>(value);
-    }
-    return true;
-  } else if (object->IsUndefined(isolate) || object->IsNull(isolate)) {
-    *out = 0;
-    return true;
-  } else if (object->IsBoolean()) {
-    *out = object->IsTrue(isolate);
-    return true;
-  }
-  return false;
-}
-
-
-inline bool GetSloppyArgumentsLength(Isolate* isolate, Handle<JSObject> object,
-                                     int* out) {
-  Context* context = *isolate->native_context();
-  Map* map = object->map();
-  if (map != context->sloppy_arguments_map() &&
-      map != context->strict_arguments_map() &&
-      map != context->fast_aliased_arguments_map()) {
-    return false;
-  }
-  DCHECK(object->HasFastElements() || object->HasFastArgumentsElements());
-  Object* len_obj = object->InObjectPropertyAt(JSArgumentsObject::kLengthIndex);
-  if (!len_obj->IsSmi()) return false;
-  *out = Max(0, Smi::cast(len_obj)->value());
-  return *out <= object->elements()->length();
-}
-
-inline bool PrototypeHasNoElements(Isolate* isolate, JSObject* object) {
-  DisallowHeapAllocation no_gc;
-  HeapObject* prototype = HeapObject::cast(object->map()->prototype());
-  HeapObject* null = isolate->heap()->null_value();
-  HeapObject* empty = isolate->heap()->empty_fixed_array();
-  while (prototype != null) {
-    Map* map = prototype->map();
-    if (map->instance_type() <= LAST_CUSTOM_ELEMENTS_RECEIVER) return false;
-    if (JSObject::cast(prototype)->elements() != empty) return false;
-    prototype = HeapObject::cast(map->prototype());
-  }
-  return true;
-}
-
-inline bool IsJSArrayFastElementMovingAllowed(Isolate* isolate,
-                                              JSArray* receiver) {
-  return PrototypeHasNoElements(isolate, receiver);
-}
-
-inline bool HasSimpleElements(JSObject* current) {
-  return current->map()->instance_type() > LAST_CUSTOM_ELEMENTS_RECEIVER &&
-         !current->GetElementsAccessor()->HasAccessors(current);
-}
-
-inline bool HasOnlySimpleReceiverElements(Isolate* isolate,
-                                          JSObject* receiver) {
-  // Check that we have no accessors on the receiver's elements.
-  if (!HasSimpleElements(receiver)) return false;
-  return PrototypeHasNoElements(isolate, receiver);
-}
-
-inline bool HasOnlySimpleElements(Isolate* isolate, JSReceiver* receiver) {
-  DisallowHeapAllocation no_gc;
-  PrototypeIterator iter(isolate, receiver, kStartAtReceiver);
-  for (; !iter.IsAtEnd(); iter.Advance()) {
-    if (iter.GetCurrent()->IsJSProxy()) return false;
-    JSObject* current = iter.GetCurrent<JSObject>();
-    if (!HasSimpleElements(current)) return false;
-  }
-  return true;
-}
-
-// Returns |false| if not applicable.
-MUST_USE_RESULT
-inline bool EnsureJSArrayWithWritableFastElements(Isolate* isolate,
-                                                  Handle<Object> receiver,
-                                                  BuiltinArguments* args,
-                                                  int first_added_arg) {
-  if (!receiver->IsJSArray()) return false;
-  Handle<JSArray> array = Handle<JSArray>::cast(receiver);
-  ElementsKind origin_kind = array->GetElementsKind();
-  if (IsDictionaryElementsKind(origin_kind)) return false;
-  if (!array->map()->is_extensible()) return false;
-  if (args == nullptr) return true;
-
-  // If there may be elements accessors in the prototype chain, the fast path
-  // cannot be used if there arguments to add to the array.
-  if (!IsJSArrayFastElementMovingAllowed(isolate, *array)) return false;
-
-  // Adding elements to the array prototype would break code that makes sure
-  // it has no elements. Handle that elsewhere.
-  if (isolate->IsAnyInitialArrayPrototype(array)) return false;
-
-  // Need to ensure that the arguments passed in args can be contained in
-  // the array.
-  int args_length = args->length();
-  if (first_added_arg >= args_length) return true;
-
-  if (IsFastObjectElementsKind(origin_kind)) return true;
-  ElementsKind target_kind = origin_kind;
-  {
-    DisallowHeapAllocation no_gc;
-    for (int i = first_added_arg; i < args_length; i++) {
-      Object* arg = (*args)[i];
-      if (arg->IsHeapObject()) {
-        if (arg->IsHeapNumber()) {
-          target_kind = FAST_DOUBLE_ELEMENTS;
-        } else {
-          target_kind = FAST_ELEMENTS;
-          break;
-        }
-      }
-    }
-  }
-  if (target_kind != origin_kind) {
-    // Use a short-lived HandleScope to avoid creating several copies of the
-    // elements handle which would cause issues when left-trimming later-on.
-    HandleScope scope(isolate);
-    JSObject::TransitionElementsKind(array, target_kind);
-  }
-  return true;
-}
-
-MUST_USE_RESULT static Object* CallJsIntrinsic(Isolate* isolate,
-                                               Handle<JSFunction> function,
-                                               BuiltinArguments args) {
-  HandleScope handleScope(isolate);
-  int argc = args.length() - 1;
-  ScopedVector<Handle<Object> > argv(argc);
-  for (int i = 0; i < argc; ++i) {
-    argv[i] = args.at<Object>(i + 1);
-  }
-  RETURN_RESULT_OR_FAILURE(
-      isolate,
-      Execution::Call(isolate, function, args.receiver(), argc, argv.start()));
-}
-
-
-}  // namespace
-
-
-BUILTIN(Illegal) {
-  UNREACHABLE();
-  return isolate->heap()->undefined_value();  // Make compiler happy.
-}
-
-
-BUILTIN(EmptyFunction) { return isolate->heap()->undefined_value(); }
-
-void Builtins::Generate_ArrayIsArray(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-  typedef CodeStubAssembler::Label Label;
-
-  Node* object = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-
-  Label call_runtime(assembler), return_true(assembler),
-      return_false(assembler);
-
-  assembler->GotoIf(assembler->WordIsSmi(object), &return_false);
-  Node* instance_type = assembler->LoadInstanceType(object);
-
-  assembler->GotoIf(assembler->Word32Equal(
-                        instance_type, assembler->Int32Constant(JS_ARRAY_TYPE)),
-                    &return_true);
-
-  // TODO(verwaest): Handle proxies in-place.
-  assembler->Branch(assembler->Word32Equal(
-                        instance_type, assembler->Int32Constant(JS_PROXY_TYPE)),
-                    &call_runtime, &return_false);
-
-  assembler->Bind(&return_true);
-  assembler->Return(assembler->BooleanConstant(true));
-
-  assembler->Bind(&return_false);
-  assembler->Return(assembler->BooleanConstant(false));
-
-  assembler->Bind(&call_runtime);
-  assembler->Return(
-      assembler->CallRuntime(Runtime::kArrayIsArray, context, object));
-}
-
-void Builtins::Generate_ObjectHasOwnProperty(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-  typedef CodeStubAssembler::Label Label;
-  typedef CodeStubAssembler::Variable Variable;
-
-  Node* object = assembler->Parameter(0);
-  Node* key = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-
-  Label call_runtime(assembler), return_true(assembler),
-      return_false(assembler);
-
-  // Smi receivers do not have own properties.
-  Label if_objectisnotsmi(assembler);
-  assembler->Branch(assembler->WordIsSmi(object), &return_false,
-                    &if_objectisnotsmi);
-  assembler->Bind(&if_objectisnotsmi);
-
-  Node* map = assembler->LoadMap(object);
-  Node* instance_type = assembler->LoadMapInstanceType(map);
-
-  Variable var_index(assembler, MachineRepresentation::kWord32);
-
-  Label keyisindex(assembler), if_iskeyunique(assembler);
-  assembler->TryToName(key, &keyisindex, &var_index, &if_iskeyunique,
-                       &call_runtime);
-
-  assembler->Bind(&if_iskeyunique);
-  assembler->TryHasOwnProperty(object, map, instance_type, key, &return_true,
-                               &return_false, &call_runtime);
-
-  assembler->Bind(&keyisindex);
-  assembler->TryLookupElement(object, map, instance_type, var_index.value(),
-                              &return_true, &return_false, &call_runtime);
-
-  assembler->Bind(&return_true);
-  assembler->Return(assembler->BooleanConstant(true));
-
-  assembler->Bind(&return_false);
-  assembler->Return(assembler->BooleanConstant(false));
-
-  assembler->Bind(&call_runtime);
-  assembler->Return(assembler->CallRuntime(Runtime::kObjectHasOwnProperty,
-                                           context, object, key));
-}
-
-namespace {
-
-Object* DoArrayPush(Isolate* isolate, BuiltinArguments args) {
-  HandleScope scope(isolate);
-  Handle<Object> receiver = args.receiver();
-  if (!EnsureJSArrayWithWritableFastElements(isolate, receiver, &args, 1)) {
-    return CallJsIntrinsic(isolate, isolate->array_push(), args);
-  }
-  // Fast Elements Path
-  int to_add = args.length() - 1;
-  Handle<JSArray> array = Handle<JSArray>::cast(receiver);
-  int len = Smi::cast(array->length())->value();
-  if (to_add == 0) return Smi::FromInt(len);
-
-  // Currently fixed arrays cannot grow too big, so we should never hit this.
-  DCHECK_LE(to_add, Smi::kMaxValue - Smi::cast(array->length())->value());
-
-  if (JSArray::HasReadOnlyLength(array)) {
-    return CallJsIntrinsic(isolate, isolate->array_push(), args);
-  }
-
-  ElementsAccessor* accessor = array->GetElementsAccessor();
-  int new_length = accessor->Push(array, &args, to_add);
-  return Smi::FromInt(new_length);
-}
-
-}  // namespace
-
-BUILTIN(ArrayPush) { return DoArrayPush(isolate, args); }
-
-// TODO(verwaest): This is a temporary helper until the FastArrayPush stub can
-// tailcall to the builtin directly.
-RUNTIME_FUNCTION(Runtime_ArrayPush) {
-  DCHECK_EQ(2, args.length());
-  Arguments* incoming = reinterpret_cast<Arguments*>(args[0]);
-  // Rewrap the arguments as builtins arguments.
-  int argc = incoming->length() + BuiltinArguments::kNumExtraArgsWithReceiver;
-  BuiltinArguments caller_args(argc, incoming->arguments() + 1);
-  return DoArrayPush(isolate, caller_args);
-}
-
-BUILTIN(ArrayPop) {
-  HandleScope scope(isolate);
-  Handle<Object> receiver = args.receiver();
-  if (!EnsureJSArrayWithWritableFastElements(isolate, receiver, nullptr, 0)) {
-    return CallJsIntrinsic(isolate, isolate->array_pop(), args);
-  }
-
-  Handle<JSArray> array = Handle<JSArray>::cast(receiver);
-
-  uint32_t len = static_cast<uint32_t>(Smi::cast(array->length())->value());
-  if (len == 0) return isolate->heap()->undefined_value();
-
-  if (JSArray::HasReadOnlyLength(array)) {
-    return CallJsIntrinsic(isolate, isolate->array_pop(), args);
-  }
-
-  Handle<Object> result;
-  if (IsJSArrayFastElementMovingAllowed(isolate, JSArray::cast(*receiver))) {
-    // Fast Elements Path
-    result = array->GetElementsAccessor()->Pop(array);
-  } else {
-    // Use Slow Lookup otherwise
-    uint32_t new_length = len - 1;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, result, JSReceiver::GetElement(isolate, array, new_length));
-    JSArray::SetLength(array, new_length);
-  }
-  return *result;
-}
-
-
-BUILTIN(ArrayShift) {
-  HandleScope scope(isolate);
-  Heap* heap = isolate->heap();
-  Handle<Object> receiver = args.receiver();
-  if (!EnsureJSArrayWithWritableFastElements(isolate, receiver, nullptr, 0) ||
-      !IsJSArrayFastElementMovingAllowed(isolate, JSArray::cast(*receiver))) {
-    return CallJsIntrinsic(isolate, isolate->array_shift(), args);
-  }
-  Handle<JSArray> array = Handle<JSArray>::cast(receiver);
-
-  int len = Smi::cast(array->length())->value();
-  if (len == 0) return heap->undefined_value();
-
-  if (JSArray::HasReadOnlyLength(array)) {
-    return CallJsIntrinsic(isolate, isolate->array_shift(), args);
-  }
-
-  Handle<Object> first = array->GetElementsAccessor()->Shift(array);
-  return *first;
-}
-
-
-BUILTIN(ArrayUnshift) {
-  HandleScope scope(isolate);
-  Handle<Object> receiver = args.receiver();
-  if (!EnsureJSArrayWithWritableFastElements(isolate, receiver, &args, 1)) {
-    return CallJsIntrinsic(isolate, isolate->array_unshift(), args);
-  }
-  Handle<JSArray> array = Handle<JSArray>::cast(receiver);
-  int to_add = args.length() - 1;
-  if (to_add == 0) return array->length();
-
-  // Currently fixed arrays cannot grow too big, so we should never hit this.
-  DCHECK_LE(to_add, Smi::kMaxValue - Smi::cast(array->length())->value());
-
-  if (JSArray::HasReadOnlyLength(array)) {
-    return CallJsIntrinsic(isolate, isolate->array_unshift(), args);
-  }
-
-  ElementsAccessor* accessor = array->GetElementsAccessor();
-  int new_length = accessor->Unshift(array, &args, to_add);
-  return Smi::FromInt(new_length);
-}
-
-
-BUILTIN(ArraySlice) {
-  HandleScope scope(isolate);
-  Handle<Object> receiver = args.receiver();
-  int len = -1;
-  int relative_start = 0;
-  int relative_end = 0;
-
-  if (receiver->IsJSArray()) {
-    DisallowHeapAllocation no_gc;
-    JSArray* array = JSArray::cast(*receiver);
-    if (V8_UNLIKELY(!array->HasFastElements() ||
-                    !IsJSArrayFastElementMovingAllowed(isolate, array) ||
-                    !isolate->IsArraySpeciesLookupChainIntact() ||
-                    // If this is a subclass of Array, then call out to JS
-                    !array->HasArrayPrototype(isolate))) {
-      AllowHeapAllocation allow_allocation;
-      return CallJsIntrinsic(isolate, isolate->array_slice(), args);
-    }
-    len = Smi::cast(array->length())->value();
-  } else if (receiver->IsJSObject() &&
-             GetSloppyArgumentsLength(isolate, Handle<JSObject>::cast(receiver),
-                                      &len)) {
-    // Array.prototype.slice.call(arguments, ...) is quite a common idiom
-    // (notably more than 50% of invocations in Web apps).
-    // Treat it in C++ as well.
-    DCHECK(JSObject::cast(*receiver)->HasFastElements() ||
-           JSObject::cast(*receiver)->HasFastArgumentsElements());
-  } else {
-    AllowHeapAllocation allow_allocation;
-    return CallJsIntrinsic(isolate, isolate->array_slice(), args);
-  }
-  DCHECK_LE(0, len);
-  int argument_count = args.length() - 1;
-  // Note carefully chosen defaults---if argument is missing,
-  // it's undefined which gets converted to 0 for relative_start
-  // and to len for relative_end.
-  relative_start = 0;
-  relative_end = len;
-  if (argument_count > 0) {
-    DisallowHeapAllocation no_gc;
-    if (!ClampedToInteger(isolate, args[1], &relative_start)) {
-      AllowHeapAllocation allow_allocation;
-      return CallJsIntrinsic(isolate, isolate->array_slice(), args);
-    }
-    if (argument_count > 1) {
-      Object* end_arg = args[2];
-      // slice handles the end_arg specially
-      if (end_arg->IsUndefined(isolate)) {
-        relative_end = len;
-      } else if (!ClampedToInteger(isolate, end_arg, &relative_end)) {
-        AllowHeapAllocation allow_allocation;
-        return CallJsIntrinsic(isolate, isolate->array_slice(), args);
-      }
-    }
-  }
-
-  // ECMAScript 232, 3rd Edition, Section 15.4.4.10, step 6.
-  uint32_t actual_start = (relative_start < 0) ? Max(len + relative_start, 0)
-                                               : Min(relative_start, len);
-
-  // ECMAScript 232, 3rd Edition, Section 15.4.4.10, step 8.
-  uint32_t actual_end =
-      (relative_end < 0) ? Max(len + relative_end, 0) : Min(relative_end, len);
-
-  Handle<JSObject> object = Handle<JSObject>::cast(receiver);
-  ElementsAccessor* accessor = object->GetElementsAccessor();
-  return *accessor->Slice(object, actual_start, actual_end);
-}
-
-
-BUILTIN(ArraySplice) {
-  HandleScope scope(isolate);
-  Handle<Object> receiver = args.receiver();
-  if (V8_UNLIKELY(
-          !EnsureJSArrayWithWritableFastElements(isolate, receiver, &args, 3) ||
-          // If this is a subclass of Array, then call out to JS.
-          !Handle<JSArray>::cast(receiver)->HasArrayPrototype(isolate) ||
-          // If anything with @@species has been messed with, call out to JS.
-          !isolate->IsArraySpeciesLookupChainIntact())) {
-    return CallJsIntrinsic(isolate, isolate->array_splice(), args);
-  }
-  Handle<JSArray> array = Handle<JSArray>::cast(receiver);
-
-  int argument_count = args.length() - 1;
-  int relative_start = 0;
-  if (argument_count > 0) {
-    DisallowHeapAllocation no_gc;
-    if (!ClampedToInteger(isolate, args[1], &relative_start)) {
-      AllowHeapAllocation allow_allocation;
-      return CallJsIntrinsic(isolate, isolate->array_splice(), args);
-    }
-  }
-  int len = Smi::cast(array->length())->value();
-  // clip relative start to [0, len]
-  int actual_start = (relative_start < 0) ? Max(len + relative_start, 0)
-                                          : Min(relative_start, len);
-
-  int actual_delete_count;
-  if (argument_count == 1) {
-    // SpiderMonkey, TraceMonkey and JSC treat the case where no delete count is
-    // given as a request to delete all the elements from the start.
-    // And it differs from the case of undefined delete count.
-    // This does not follow ECMA-262, but we do the same for compatibility.
-    DCHECK(len - actual_start >= 0);
-    actual_delete_count = len - actual_start;
-  } else {
-    int delete_count = 0;
-    DisallowHeapAllocation no_gc;
-    if (argument_count > 1) {
-      if (!ClampedToInteger(isolate, args[2], &delete_count)) {
-        AllowHeapAllocation allow_allocation;
-        return CallJsIntrinsic(isolate, isolate->array_splice(), args);
-      }
-    }
-    actual_delete_count = Min(Max(delete_count, 0), len - actual_start);
-  }
-
-  int add_count = (argument_count > 1) ? (argument_count - 2) : 0;
-  int new_length = len - actual_delete_count + add_count;
-
-  if (new_length != len && JSArray::HasReadOnlyLength(array)) {
-    AllowHeapAllocation allow_allocation;
-    return CallJsIntrinsic(isolate, isolate->array_splice(), args);
-  }
-  ElementsAccessor* accessor = array->GetElementsAccessor();
-  Handle<JSArray> result_array = accessor->Splice(
-      array, actual_start, actual_delete_count, &args, add_count);
-  return *result_array;
-}
-
-
-// Array Concat -------------------------------------------------------------
-
-namespace {
-
-/**
- * A simple visitor visits every element of Array's.
- * The backend storage can be a fixed array for fast elements case,
- * or a dictionary for sparse array. Since Dictionary is a subtype
- * of FixedArray, the class can be used by both fast and slow cases.
- * The second parameter of the constructor, fast_elements, specifies
- * whether the storage is a FixedArray or Dictionary.
- *
- * An index limit is used to deal with the situation that a result array
- * length overflows 32-bit non-negative integer.
- */
-class ArrayConcatVisitor {
- public:
-  ArrayConcatVisitor(Isolate* isolate, Handle<Object> storage,
-                     bool fast_elements)
-      : isolate_(isolate),
-        storage_(isolate->global_handles()->Create(*storage)),
-        index_offset_(0u),
-        bit_field_(FastElementsField::encode(fast_elements) |
-                   ExceedsLimitField::encode(false) |
-                   IsFixedArrayField::encode(storage->IsFixedArray())) {
-    DCHECK(!(this->fast_elements() && !is_fixed_array()));
-  }
-
-  ~ArrayConcatVisitor() { clear_storage(); }
-
-  MUST_USE_RESULT bool visit(uint32_t i, Handle<Object> elm) {
-    uint32_t index = index_offset_ + i;
-
-    if (i >= JSObject::kMaxElementCount - index_offset_) {
-      set_exceeds_array_limit(true);
-      // Exception hasn't been thrown at this point. Return true to
-      // break out, and caller will throw. !visit would imply that
-      // there is already a pending exception.
-      return true;
-    }
-
-    if (!is_fixed_array()) {
-      LookupIterator it(isolate_, storage_, index, LookupIterator::OWN);
-      MAYBE_RETURN(
-          JSReceiver::CreateDataProperty(&it, elm, Object::THROW_ON_ERROR),
-          false);
-      return true;
-    }
-
-    if (fast_elements()) {
-      if (index < static_cast<uint32_t>(storage_fixed_array()->length())) {
-        storage_fixed_array()->set(index, *elm);
-        return true;
-      }
-      // Our initial estimate of length was foiled, possibly by
-      // getters on the arrays increasing the length of later arrays
-      // during iteration.
-      // This shouldn't happen in anything but pathological cases.
-      SetDictionaryMode();
-      // Fall-through to dictionary mode.
-    }
-    DCHECK(!fast_elements());
-    Handle<SeededNumberDictionary> dict(
-        SeededNumberDictionary::cast(*storage_));
-    // The object holding this backing store has just been allocated, so
-    // it cannot yet be used as a prototype.
-    Handle<SeededNumberDictionary> result =
-        SeededNumberDictionary::AtNumberPut(dict, index, elm, false);
-    if (!result.is_identical_to(dict)) {
-      // Dictionary needed to grow.
-      clear_storage();
-      set_storage(*result);
-    }
-    return true;
-  }
-
-  void increase_index_offset(uint32_t delta) {
-    if (JSObject::kMaxElementCount - index_offset_ < delta) {
-      index_offset_ = JSObject::kMaxElementCount;
-    } else {
-      index_offset_ += delta;
-    }
-    // If the initial length estimate was off (see special case in visit()),
-    // but the array blowing the limit didn't contain elements beyond the
-    // provided-for index range, go to dictionary mode now.
-    if (fast_elements() &&
-        index_offset_ >
-            static_cast<uint32_t>(FixedArrayBase::cast(*storage_)->length())) {
-      SetDictionaryMode();
-    }
-  }
-
-  bool exceeds_array_limit() const {
-    return ExceedsLimitField::decode(bit_field_);
-  }
-
-  Handle<JSArray> ToArray() {
-    DCHECK(is_fixed_array());
-    Handle<JSArray> array = isolate_->factory()->NewJSArray(0);
-    Handle<Object> length =
-        isolate_->factory()->NewNumber(static_cast<double>(index_offset_));
-    Handle<Map> map = JSObject::GetElementsTransitionMap(
-        array, fast_elements() ? FAST_HOLEY_ELEMENTS : DICTIONARY_ELEMENTS);
-    array->set_map(*map);
-    array->set_length(*length);
-    array->set_elements(*storage_fixed_array());
-    return array;
-  }
-
-  // Storage is either a FixedArray (if is_fixed_array()) or a JSReciever
-  // (otherwise)
-  Handle<FixedArray> storage_fixed_array() {
-    DCHECK(is_fixed_array());
-    return Handle<FixedArray>::cast(storage_);
-  }
-  Handle<JSReceiver> storage_jsreceiver() {
-    DCHECK(!is_fixed_array());
-    return Handle<JSReceiver>::cast(storage_);
-  }
-
- private:
-  // Convert storage to dictionary mode.
-  void SetDictionaryMode() {
-    DCHECK(fast_elements() && is_fixed_array());
-    Handle<FixedArray> current_storage = storage_fixed_array();
-    Handle<SeededNumberDictionary> slow_storage(
-        SeededNumberDictionary::New(isolate_, current_storage->length()));
-    uint32_t current_length = static_cast<uint32_t>(current_storage->length());
-    FOR_WITH_HANDLE_SCOPE(
-        isolate_, uint32_t, i = 0, i, i < current_length, i++, {
-          Handle<Object> element(current_storage->get(i), isolate_);
-          if (!element->IsTheHole(isolate_)) {
-            // The object holding this backing store has just been allocated, so
-            // it cannot yet be used as a prototype.
-            Handle<SeededNumberDictionary> new_storage =
-                SeededNumberDictionary::AtNumberPut(slow_storage, i, element,
-                                                    false);
-            if (!new_storage.is_identical_to(slow_storage)) {
-              slow_storage = loop_scope.CloseAndEscape(new_storage);
-            }
-          }
-        });
-    clear_storage();
-    set_storage(*slow_storage);
-    set_fast_elements(false);
-  }
-
-  inline void clear_storage() { GlobalHandles::Destroy(storage_.location()); }
-
-  inline void set_storage(FixedArray* storage) {
-    DCHECK(is_fixed_array());
-    storage_ = isolate_->global_handles()->Create(storage);
-  }
-
-  class FastElementsField : public BitField<bool, 0, 1> {};
-  class ExceedsLimitField : public BitField<bool, 1, 1> {};
-  class IsFixedArrayField : public BitField<bool, 2, 1> {};
-
-  bool fast_elements() const { return FastElementsField::decode(bit_field_); }
-  void set_fast_elements(bool fast) {
-    bit_field_ = FastElementsField::update(bit_field_, fast);
-  }
-  void set_exceeds_array_limit(bool exceeds) {
-    bit_field_ = ExceedsLimitField::update(bit_field_, exceeds);
-  }
-  bool is_fixed_array() const { return IsFixedArrayField::decode(bit_field_); }
-
-  Isolate* isolate_;
-  Handle<Object> storage_;  // Always a global handle.
-  // Index after last seen index. Always less than or equal to
-  // JSObject::kMaxElementCount.
-  uint32_t index_offset_;
-  uint32_t bit_field_;
-};
-
-
-uint32_t EstimateElementCount(Handle<JSArray> array) {
-  DisallowHeapAllocation no_gc;
-  uint32_t length = static_cast<uint32_t>(array->length()->Number());
-  int element_count = 0;
-  switch (array->GetElementsKind()) {
-    case FAST_SMI_ELEMENTS:
-    case FAST_HOLEY_SMI_ELEMENTS:
-    case FAST_ELEMENTS:
-    case FAST_HOLEY_ELEMENTS: {
-      // Fast elements can't have lengths that are not representable by
-      // a 32-bit signed integer.
-      DCHECK(static_cast<int32_t>(FixedArray::kMaxLength) >= 0);
-      int fast_length = static_cast<int>(length);
-      Isolate* isolate = array->GetIsolate();
-      FixedArray* elements = FixedArray::cast(array->elements());
-      for (int i = 0; i < fast_length; i++) {
-        if (!elements->get(i)->IsTheHole(isolate)) element_count++;
-      }
-      break;
-    }
-    case FAST_DOUBLE_ELEMENTS:
-    case FAST_HOLEY_DOUBLE_ELEMENTS: {
-      // Fast elements can't have lengths that are not representable by
-      // a 32-bit signed integer.
-      DCHECK(static_cast<int32_t>(FixedDoubleArray::kMaxLength) >= 0);
-      int fast_length = static_cast<int>(length);
-      if (array->elements()->IsFixedArray()) {
-        DCHECK(FixedArray::cast(array->elements())->length() == 0);
-        break;
-      }
-      FixedDoubleArray* elements = FixedDoubleArray::cast(array->elements());
-      for (int i = 0; i < fast_length; i++) {
-        if (!elements->is_the_hole(i)) element_count++;
-      }
-      break;
-    }
-    case DICTIONARY_ELEMENTS: {
-      SeededNumberDictionary* dictionary =
-          SeededNumberDictionary::cast(array->elements());
-      Isolate* isolate = dictionary->GetIsolate();
-      int capacity = dictionary->Capacity();
-      for (int i = 0; i < capacity; i++) {
-        Object* key = dictionary->KeyAt(i);
-        if (dictionary->IsKey(isolate, key)) {
-          element_count++;
-        }
-      }
-      break;
-    }
-#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) case TYPE##_ELEMENTS:
-
-      TYPED_ARRAYS(TYPED_ARRAY_CASE)
-#undef TYPED_ARRAY_CASE
-      // External arrays are always dense.
-      return length;
-    case NO_ELEMENTS:
-      return 0;
-    case FAST_SLOPPY_ARGUMENTS_ELEMENTS:
-    case SLOW_SLOPPY_ARGUMENTS_ELEMENTS:
-    case FAST_STRING_WRAPPER_ELEMENTS:
-    case SLOW_STRING_WRAPPER_ELEMENTS:
-      UNREACHABLE();
-      return 0;
-  }
-  // As an estimate, we assume that the prototype doesn't contain any
-  // inherited elements.
-  return element_count;
-}
-
-
-// Used for sorting indices in a List<uint32_t>.
-int compareUInt32(const uint32_t* ap, const uint32_t* bp) {
-  uint32_t a = *ap;
-  uint32_t b = *bp;
-  return (a == b) ? 0 : (a < b) ? -1 : 1;
-}
-
-
-void CollectElementIndices(Handle<JSObject> object, uint32_t range,
-                           List<uint32_t>* indices) {
-  Isolate* isolate = object->GetIsolate();
-  ElementsKind kind = object->GetElementsKind();
-  switch (kind) {
-    case FAST_SMI_ELEMENTS:
-    case FAST_ELEMENTS:
-    case FAST_HOLEY_SMI_ELEMENTS:
-    case FAST_HOLEY_ELEMENTS: {
-      DisallowHeapAllocation no_gc;
-      FixedArray* elements = FixedArray::cast(object->elements());
-      uint32_t length = static_cast<uint32_t>(elements->length());
-      if (range < length) length = range;
-      for (uint32_t i = 0; i < length; i++) {
-        if (!elements->get(i)->IsTheHole(isolate)) {
-          indices->Add(i);
-        }
-      }
-      break;
-    }
-    case FAST_HOLEY_DOUBLE_ELEMENTS:
-    case FAST_DOUBLE_ELEMENTS: {
-      if (object->elements()->IsFixedArray()) {
-        DCHECK(object->elements()->length() == 0);
-        break;
-      }
-      Handle<FixedDoubleArray> elements(
-          FixedDoubleArray::cast(object->elements()));
-      uint32_t length = static_cast<uint32_t>(elements->length());
-      if (range < length) length = range;
-      for (uint32_t i = 0; i < length; i++) {
-        if (!elements->is_the_hole(i)) {
-          indices->Add(i);
-        }
-      }
-      break;
-    }
-    case DICTIONARY_ELEMENTS: {
-      DisallowHeapAllocation no_gc;
-      SeededNumberDictionary* dict =
-          SeededNumberDictionary::cast(object->elements());
-      uint32_t capacity = dict->Capacity();
-      FOR_WITH_HANDLE_SCOPE(isolate, uint32_t, j = 0, j, j < capacity, j++, {
-        Object* k = dict->KeyAt(j);
-        if (!dict->IsKey(isolate, k)) continue;
-        DCHECK(k->IsNumber());
-        uint32_t index = static_cast<uint32_t>(k->Number());
-        if (index < range) {
-          indices->Add(index);
-        }
-      });
-      break;
-    }
-#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) case TYPE##_ELEMENTS:
-
-      TYPED_ARRAYS(TYPED_ARRAY_CASE)
-#undef TYPED_ARRAY_CASE
-      {
-        uint32_t length = static_cast<uint32_t>(
-            FixedArrayBase::cast(object->elements())->length());
-        if (range <= length) {
-          length = range;
-          // We will add all indices, so we might as well clear it first
-          // and avoid duplicates.
-          indices->Clear();
-        }
-        for (uint32_t i = 0; i < length; i++) {
-          indices->Add(i);
-        }
-        if (length == range) return;  // All indices accounted for already.
-        break;
-      }
-    case FAST_SLOPPY_ARGUMENTS_ELEMENTS:
-    case SLOW_SLOPPY_ARGUMENTS_ELEMENTS: {
-      ElementsAccessor* accessor = object->GetElementsAccessor();
-      for (uint32_t i = 0; i < range; i++) {
-        if (accessor->HasElement(object, i)) {
-          indices->Add(i);
-        }
-      }
-      break;
-    }
-    case FAST_STRING_WRAPPER_ELEMENTS:
-    case SLOW_STRING_WRAPPER_ELEMENTS: {
-      DCHECK(object->IsJSValue());
-      Handle<JSValue> js_value = Handle<JSValue>::cast(object);
-      DCHECK(js_value->value()->IsString());
-      Handle<String> string(String::cast(js_value->value()), isolate);
-      uint32_t length = static_cast<uint32_t>(string->length());
-      uint32_t i = 0;
-      uint32_t limit = Min(length, range);
-      for (; i < limit; i++) {
-        indices->Add(i);
-      }
-      ElementsAccessor* accessor = object->GetElementsAccessor();
-      for (; i < range; i++) {
-        if (accessor->HasElement(object, i)) {
-          indices->Add(i);
-        }
-      }
-      break;
-    }
-    case NO_ELEMENTS:
-      break;
-  }
-
-  PrototypeIterator iter(isolate, object);
-  if (!iter.IsAtEnd()) {
-    // The prototype will usually have no inherited element indices,
-    // but we have to check.
-    CollectElementIndices(PrototypeIterator::GetCurrent<JSObject>(iter), range,
-                          indices);
-  }
-}
-
-
-bool IterateElementsSlow(Isolate* isolate, Handle<JSReceiver> receiver,
-                         uint32_t length, ArrayConcatVisitor* visitor) {
-  FOR_WITH_HANDLE_SCOPE(isolate, uint32_t, i = 0, i, i < length, ++i, {
-    Maybe<bool> maybe = JSReceiver::HasElement(receiver, i);
-    if (!maybe.IsJust()) return false;
-    if (maybe.FromJust()) {
-      Handle<Object> element_value;
-      ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-          isolate, element_value, JSReceiver::GetElement(isolate, receiver, i),
-          false);
-      if (!visitor->visit(i, element_value)) return false;
-    }
-  });
-  visitor->increase_index_offset(length);
-  return true;
-}
-
-
-/**
- * A helper function that visits "array" elements of a JSReceiver in numerical
- * order.
- *
- * The visitor argument called for each existing element in the array
- * with the element index and the element's value.
- * Afterwards it increments the base-index of the visitor by the array
- * length.
- * Returns false if any access threw an exception, otherwise true.
- */
-bool IterateElements(Isolate* isolate, Handle<JSReceiver> receiver,
-                     ArrayConcatVisitor* visitor) {
-  uint32_t length = 0;
-
-  if (receiver->IsJSArray()) {
-    Handle<JSArray> array = Handle<JSArray>::cast(receiver);
-    length = static_cast<uint32_t>(array->length()->Number());
-  } else {
-    Handle<Object> val;
-    ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-        isolate, val, Object::GetLengthFromArrayLike(isolate, receiver), false);
-    // TODO(caitp): Support larger element indexes (up to 2^53-1).
-    if (!val->ToUint32(&length)) {
-      length = 0;
-    }
-    // TODO(cbruni): handle other element kind as well
-    return IterateElementsSlow(isolate, receiver, length, visitor);
-  }
-
-  if (!HasOnlySimpleElements(isolate, *receiver)) {
-    return IterateElementsSlow(isolate, receiver, length, visitor);
-  }
-  Handle<JSObject> array = Handle<JSObject>::cast(receiver);
-
-  switch (array->GetElementsKind()) {
-    case FAST_SMI_ELEMENTS:
-    case FAST_ELEMENTS:
-    case FAST_HOLEY_SMI_ELEMENTS:
-    case FAST_HOLEY_ELEMENTS: {
-      // Run through the elements FixedArray and use HasElement and GetElement
-      // to check the prototype for missing elements.
-      Handle<FixedArray> elements(FixedArray::cast(array->elements()));
-      int fast_length = static_cast<int>(length);
-      DCHECK(fast_length <= elements->length());
-      FOR_WITH_HANDLE_SCOPE(isolate, int, j = 0, j, j < fast_length, j++, {
-        Handle<Object> element_value(elements->get(j), isolate);
-        if (!element_value->IsTheHole(isolate)) {
-          if (!visitor->visit(j, element_value)) return false;
-        } else {
-          Maybe<bool> maybe = JSReceiver::HasElement(array, j);
-          if (!maybe.IsJust()) return false;
-          if (maybe.FromJust()) {
-            // Call GetElement on array, not its prototype, or getters won't
-            // have the correct receiver.
-            ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-                isolate, element_value,
-                JSReceiver::GetElement(isolate, array, j), false);
-            if (!visitor->visit(j, element_value)) return false;
-          }
-        }
-      });
-      break;
-    }
-    case FAST_HOLEY_DOUBLE_ELEMENTS:
-    case FAST_DOUBLE_ELEMENTS: {
-      // Empty array is FixedArray but not FixedDoubleArray.
-      if (length == 0) break;
-      // Run through the elements FixedArray and use HasElement and GetElement
-      // to check the prototype for missing elements.
-      if (array->elements()->IsFixedArray()) {
-        DCHECK(array->elements()->length() == 0);
-        break;
-      }
-      Handle<FixedDoubleArray> elements(
-          FixedDoubleArray::cast(array->elements()));
-      int fast_length = static_cast<int>(length);
-      DCHECK(fast_length <= elements->length());
-      FOR_WITH_HANDLE_SCOPE(isolate, int, j = 0, j, j < fast_length, j++, {
-        if (!elements->is_the_hole(j)) {
-          double double_value = elements->get_scalar(j);
-          Handle<Object> element_value =
-              isolate->factory()->NewNumber(double_value);
-          if (!visitor->visit(j, element_value)) return false;
-        } else {
-          Maybe<bool> maybe = JSReceiver::HasElement(array, j);
-          if (!maybe.IsJust()) return false;
-          if (maybe.FromJust()) {
-            // Call GetElement on array, not its prototype, or getters won't
-            // have the correct receiver.
-            Handle<Object> element_value;
-            ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-                isolate, element_value,
-                JSReceiver::GetElement(isolate, array, j), false);
-            if (!visitor->visit(j, element_value)) return false;
-          }
-        }
-      });
-      break;
-    }
-
-    case DICTIONARY_ELEMENTS: {
-      Handle<SeededNumberDictionary> dict(array->element_dictionary());
-      List<uint32_t> indices(dict->Capacity() / 2);
-      // Collect all indices in the object and the prototypes less
-      // than length. This might introduce duplicates in the indices list.
-      CollectElementIndices(array, length, &indices);
-      indices.Sort(&compareUInt32);
-      int n = indices.length();
-      FOR_WITH_HANDLE_SCOPE(isolate, int, j = 0, j, j < n, (void)0, {
-        uint32_t index = indices[j];
-        Handle<Object> element;
-        ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-            isolate, element, JSReceiver::GetElement(isolate, array, index),
-            false);
-        if (!visitor->visit(index, element)) return false;
-        // Skip to next different index (i.e., omit duplicates).
-        do {
-          j++;
-        } while (j < n && indices[j] == index);
-      });
-      break;
-    }
-    case FAST_SLOPPY_ARGUMENTS_ELEMENTS:
-    case SLOW_SLOPPY_ARGUMENTS_ELEMENTS: {
-      FOR_WITH_HANDLE_SCOPE(
-          isolate, uint32_t, index = 0, index, index < length, index++, {
-            Handle<Object> element;
-            ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-                isolate, element, JSReceiver::GetElement(isolate, array, index),
-                false);
-            if (!visitor->visit(index, element)) return false;
-          });
-      break;
-    }
-    case NO_ELEMENTS:
-      break;
-#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) case TYPE##_ELEMENTS:
-      TYPED_ARRAYS(TYPED_ARRAY_CASE)
-#undef TYPED_ARRAY_CASE
-      return IterateElementsSlow(isolate, receiver, length, visitor);
-    case FAST_STRING_WRAPPER_ELEMENTS:
-    case SLOW_STRING_WRAPPER_ELEMENTS:
-      // |array| is guaranteed to be an array or typed array.
-      UNREACHABLE();
-      break;
-  }
-  visitor->increase_index_offset(length);
-  return true;
-}
-
-static Maybe<bool> IsConcatSpreadable(Isolate* isolate, Handle<Object> obj) {
-  HandleScope handle_scope(isolate);
-  if (!obj->IsJSReceiver()) return Just(false);
-  if (!isolate->IsIsConcatSpreadableLookupChainIntact()) {
-    // Slow path if @@isConcatSpreadable has been used.
-    Handle<Symbol> key(isolate->factory()->is_concat_spreadable_symbol());
-    Handle<Object> value;
-    MaybeHandle<Object> maybeValue =
-        i::Runtime::GetObjectProperty(isolate, obj, key);
-    if (!maybeValue.ToHandle(&value)) return Nothing<bool>();
-    if (!value->IsUndefined(isolate)) return Just(value->BooleanValue());
-  }
-  return Object::IsArray(obj);
-}
-
-Object* Slow_ArrayConcat(BuiltinArguments* args, Handle<Object> species,
-                         Isolate* isolate) {
-  int argument_count = args->length();
-
-  bool is_array_species = *species == isolate->context()->array_function();
-
-  // Pass 1: estimate the length and number of elements of the result.
-  // The actual length can be larger if any of the arguments have getters
-  // that mutate other arguments (but will otherwise be precise).
-  // The number of elements is precise if there are no inherited elements.
-
-  ElementsKind kind = FAST_SMI_ELEMENTS;
-
-  uint32_t estimate_result_length = 0;
-  uint32_t estimate_nof_elements = 0;
-  FOR_WITH_HANDLE_SCOPE(isolate, int, i = 0, i, i < argument_count, i++, {
-    Handle<Object> obj((*args)[i], isolate);
-    uint32_t length_estimate;
-    uint32_t element_estimate;
-    if (obj->IsJSArray()) {
-      Handle<JSArray> array(Handle<JSArray>::cast(obj));
-      length_estimate = static_cast<uint32_t>(array->length()->Number());
-      if (length_estimate != 0) {
-        ElementsKind array_kind =
-            GetPackedElementsKind(array->GetElementsKind());
-        kind = GetMoreGeneralElementsKind(kind, array_kind);
-      }
-      element_estimate = EstimateElementCount(array);
-    } else {
-      if (obj->IsHeapObject()) {
-        kind = GetMoreGeneralElementsKind(
-            kind, obj->IsNumber() ? FAST_DOUBLE_ELEMENTS : FAST_ELEMENTS);
-      }
-      length_estimate = 1;
-      element_estimate = 1;
-    }
-    // Avoid overflows by capping at kMaxElementCount.
-    if (JSObject::kMaxElementCount - estimate_result_length < length_estimate) {
-      estimate_result_length = JSObject::kMaxElementCount;
-    } else {
-      estimate_result_length += length_estimate;
-    }
-    if (JSObject::kMaxElementCount - estimate_nof_elements < element_estimate) {
-      estimate_nof_elements = JSObject::kMaxElementCount;
-    } else {
-      estimate_nof_elements += element_estimate;
-    }
-  });
-
-  // If estimated number of elements is more than half of length, a
-  // fixed array (fast case) is more time and space-efficient than a
-  // dictionary.
-  bool fast_case =
-      is_array_species && (estimate_nof_elements * 2) >= estimate_result_length;
-
-  if (fast_case && kind == FAST_DOUBLE_ELEMENTS) {
-    Handle<FixedArrayBase> storage =
-        isolate->factory()->NewFixedDoubleArray(estimate_result_length);
-    int j = 0;
-    bool failure = false;
-    if (estimate_result_length > 0) {
-      Handle<FixedDoubleArray> double_storage =
-          Handle<FixedDoubleArray>::cast(storage);
-      for (int i = 0; i < argument_count; i++) {
-        Handle<Object> obj((*args)[i], isolate);
-        if (obj->IsSmi()) {
-          double_storage->set(j, Smi::cast(*obj)->value());
-          j++;
-        } else if (obj->IsNumber()) {
-          double_storage->set(j, obj->Number());
-          j++;
-        } else {
-          DisallowHeapAllocation no_gc;
-          JSArray* array = JSArray::cast(*obj);
-          uint32_t length = static_cast<uint32_t>(array->length()->Number());
-          switch (array->GetElementsKind()) {
-            case FAST_HOLEY_DOUBLE_ELEMENTS:
-            case FAST_DOUBLE_ELEMENTS: {
-              // Empty array is FixedArray but not FixedDoubleArray.
-              if (length == 0) break;
-              FixedDoubleArray* elements =
-                  FixedDoubleArray::cast(array->elements());
-              for (uint32_t i = 0; i < length; i++) {
-                if (elements->is_the_hole(i)) {
-                  // TODO(jkummerow/verwaest): We could be a bit more clever
-                  // here: Check if there are no elements/getters on the
-                  // prototype chain, and if so, allow creation of a holey
-                  // result array.
-                  // Same thing below (holey smi case).
-                  failure = true;
-                  break;
-                }
-                double double_value = elements->get_scalar(i);
-                double_storage->set(j, double_value);
-                j++;
-              }
-              break;
-            }
-            case FAST_HOLEY_SMI_ELEMENTS:
-            case FAST_SMI_ELEMENTS: {
-              Object* the_hole = isolate->heap()->the_hole_value();
-              FixedArray* elements(FixedArray::cast(array->elements()));
-              for (uint32_t i = 0; i < length; i++) {
-                Object* element = elements->get(i);
-                if (element == the_hole) {
-                  failure = true;
-                  break;
-                }
-                int32_t int_value = Smi::cast(element)->value();
-                double_storage->set(j, int_value);
-                j++;
-              }
-              break;
-            }
-            case FAST_HOLEY_ELEMENTS:
-            case FAST_ELEMENTS:
-            case DICTIONARY_ELEMENTS:
-            case NO_ELEMENTS:
-              DCHECK_EQ(0u, length);
-              break;
-            default:
-              UNREACHABLE();
-          }
-        }
-        if (failure) break;
-      }
-    }
-    if (!failure) {
-      return *isolate->factory()->NewJSArrayWithElements(storage, kind, j);
-    }
-    // In case of failure, fall through.
-  }
-
-  Handle<Object> storage;
-  if (fast_case) {
-    // The backing storage array must have non-existing elements to preserve
-    // holes across concat operations.
-    storage =
-        isolate->factory()->NewFixedArrayWithHoles(estimate_result_length);
-  } else if (is_array_species) {
-    // TODO(126): move 25% pre-allocation logic into Dictionary::Allocate
-    uint32_t at_least_space_for =
-        estimate_nof_elements + (estimate_nof_elements >> 2);
-    storage = SeededNumberDictionary::New(isolate, at_least_space_for);
-  } else {
-    DCHECK(species->IsConstructor());
-    Handle<Object> length(Smi::FromInt(0), isolate);
-    Handle<Object> storage_object;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, storage_object,
-        Execution::New(isolate, species, species, 1, &length));
-    storage = storage_object;
-  }
-
-  ArrayConcatVisitor visitor(isolate, storage, fast_case);
-
-  for (int i = 0; i < argument_count; i++) {
-    Handle<Object> obj((*args)[i], isolate);
-    Maybe<bool> spreadable = IsConcatSpreadable(isolate, obj);
-    MAYBE_RETURN(spreadable, isolate->heap()->exception());
-    if (spreadable.FromJust()) {
-      Handle<JSReceiver> object = Handle<JSReceiver>::cast(obj);
-      if (!IterateElements(isolate, object, &visitor)) {
-        return isolate->heap()->exception();
-      }
-    } else {
-      if (!visitor.visit(0, obj)) return isolate->heap()->exception();
-      visitor.increase_index_offset(1);
-    }
-  }
-
-  if (visitor.exceeds_array_limit()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kInvalidArrayLength));
-  }
-
-  if (is_array_species) {
-    return *visitor.ToArray();
-  } else {
-    return *visitor.storage_jsreceiver();
-  }
-}
-
-bool IsSimpleArray(Isolate* isolate, Handle<JSArray> obj) {
-  DisallowHeapAllocation no_gc;
-  Map* map = obj->map();
-  // If there is only the 'length' property we are fine.
-  if (map->prototype() ==
-          isolate->native_context()->initial_array_prototype() &&
-      map->NumberOfOwnDescriptors() == 1) {
-    return true;
-  }
-  // TODO(cbruni): slower lookup for array subclasses and support slow
-  // @@IsConcatSpreadable lookup.
-  return false;
-}
-
-MaybeHandle<JSArray> Fast_ArrayConcat(Isolate* isolate,
-                                      BuiltinArguments* args) {
-  if (!isolate->IsIsConcatSpreadableLookupChainIntact()) {
-    return MaybeHandle<JSArray>();
-  }
-  // We shouldn't overflow when adding another len.
-  const int kHalfOfMaxInt = 1 << (kBitsPerInt - 2);
-  STATIC_ASSERT(FixedArray::kMaxLength < kHalfOfMaxInt);
-  STATIC_ASSERT(FixedDoubleArray::kMaxLength < kHalfOfMaxInt);
-  USE(kHalfOfMaxInt);
-
-  int n_arguments = args->length();
-  int result_len = 0;
-  {
-    DisallowHeapAllocation no_gc;
-    // Iterate through all the arguments performing checks
-    // and calculating total length.
-    for (int i = 0; i < n_arguments; i++) {
-      Object* arg = (*args)[i];
-      if (!arg->IsJSArray()) return MaybeHandle<JSArray>();
-      if (!HasOnlySimpleReceiverElements(isolate, JSObject::cast(arg))) {
-        return MaybeHandle<JSArray>();
-      }
-      // TODO(cbruni): support fast concatenation of DICTIONARY_ELEMENTS.
-      if (!JSObject::cast(arg)->HasFastElements()) {
-        return MaybeHandle<JSArray>();
-      }
-      Handle<JSArray> array(JSArray::cast(arg), isolate);
-      if (!IsSimpleArray(isolate, array)) {
-        return MaybeHandle<JSArray>();
-      }
-      // The Array length is guaranted to be <= kHalfOfMaxInt thus we won't
-      // overflow.
-      result_len += Smi::cast(array->length())->value();
-      DCHECK(result_len >= 0);
-      // Throw an Error if we overflow the FixedArray limits
-      if (FixedDoubleArray::kMaxLength < result_len ||
-          FixedArray::kMaxLength < result_len) {
-        AllowHeapAllocation gc;
-        THROW_NEW_ERROR(isolate,
-                        NewRangeError(MessageTemplate::kInvalidArrayLength),
-                        JSArray);
-      }
-    }
-  }
-  return ElementsAccessor::Concat(isolate, args, n_arguments, result_len);
-}
-
-}  // namespace
-
-
-// ES6 22.1.3.1 Array.prototype.concat
-BUILTIN(ArrayConcat) {
-  HandleScope scope(isolate);
-
-  Handle<Object> receiver = args.receiver();
-  // TODO(bmeurer): Do we really care about the exact exception message here?
-  if (receiver->IsNull(isolate) || receiver->IsUndefined(isolate)) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNullOrUndefined,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Array.prototype.concat")));
-  }
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, receiver, Object::ToObject(isolate, args.receiver()));
-  args[0] = *receiver;
-
-  Handle<JSArray> result_array;
-
-  // Avoid a real species read to avoid extra lookups to the array constructor
-  if (V8_LIKELY(receiver->IsJSArray() &&
-                Handle<JSArray>::cast(receiver)->HasArrayPrototype(isolate) &&
-                isolate->IsArraySpeciesLookupChainIntact())) {
-    if (Fast_ArrayConcat(isolate, &args).ToHandle(&result_array)) {
-      return *result_array;
-    }
-    if (isolate->has_pending_exception()) return isolate->heap()->exception();
-  }
-  // Reading @@species happens before anything else with a side effect, so
-  // we can do it here to determine whether to take the fast path.
-  Handle<Object> species;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, species, Object::ArraySpeciesConstructor(isolate, receiver));
-  if (*species == *isolate->array_function()) {
-    if (Fast_ArrayConcat(isolate, &args).ToHandle(&result_array)) {
-      return *result_array;
-    }
-    if (isolate->has_pending_exception()) return isolate->heap()->exception();
-  }
-  return Slow_ArrayConcat(&args, species, isolate);
-}
-
-
-namespace {
-
-MUST_USE_RESULT Maybe<bool> FastAssign(Handle<JSReceiver> to,
-                                       Handle<Object> next_source) {
-  // Non-empty strings are the only non-JSReceivers that need to be handled
-  // explicitly by Object.assign.
-  if (!next_source->IsJSReceiver()) {
-    return Just(!next_source->IsString() ||
-                String::cast(*next_source)->length() == 0);
-  }
-
-  // If the target is deprecated, the object will be updated on first store. If
-  // the source for that store equals the target, this will invalidate the
-  // cached representation of the source. Preventively upgrade the target.
-  // Do this on each iteration since any property load could cause deprecation.
-  if (to->map()->is_deprecated()) {
-    JSObject::MigrateInstance(Handle<JSObject>::cast(to));
-  }
-
-  Isolate* isolate = to->GetIsolate();
-  Handle<Map> map(JSReceiver::cast(*next_source)->map(), isolate);
-
-  if (!map->IsJSObjectMap()) return Just(false);
-  if (!map->OnlyHasSimpleProperties()) return Just(false);
-
-  Handle<JSObject> from = Handle<JSObject>::cast(next_source);
-  if (from->elements() != isolate->heap()->empty_fixed_array()) {
-    return Just(false);
-  }
-
-  Handle<DescriptorArray> descriptors(map->instance_descriptors(), isolate);
-  int length = map->NumberOfOwnDescriptors();
-
-  bool stable = true;
-
-  for (int i = 0; i < length; i++) {
-    Handle<Name> next_key(descriptors->GetKey(i), isolate);
-    Handle<Object> prop_value;
-    // Directly decode from the descriptor array if |from| did not change shape.
-    if (stable) {
-      PropertyDetails details = descriptors->GetDetails(i);
-      if (!details.IsEnumerable()) continue;
-      if (details.kind() == kData) {
-        if (details.location() == kDescriptor) {
-          prop_value = handle(descriptors->GetValue(i), isolate);
-        } else {
-          Representation representation = details.representation();
-          FieldIndex index = FieldIndex::ForDescriptor(*map, i);
-          prop_value = JSObject::FastPropertyAt(from, representation, index);
-        }
-      } else {
-        ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-            isolate, prop_value, JSReceiver::GetProperty(from, next_key),
-            Nothing<bool>());
-        stable = from->map() == *map;
-      }
-    } else {
-      // If the map did change, do a slower lookup. We are still guaranteed that
-      // the object has a simple shape, and that the key is a name.
-      LookupIterator it(from, next_key, from,
-                        LookupIterator::OWN_SKIP_INTERCEPTOR);
-      if (!it.IsFound()) continue;
-      DCHECK(it.state() == LookupIterator::DATA ||
-             it.state() == LookupIterator::ACCESSOR);
-      if (!it.IsEnumerable()) continue;
-      ASSIGN_RETURN_ON_EXCEPTION_VALUE(
-          isolate, prop_value, Object::GetProperty(&it), Nothing<bool>());
-    }
-    LookupIterator it(to, next_key, to);
-    bool call_to_js = it.IsFound() && it.state() != LookupIterator::DATA;
-    Maybe<bool> result = Object::SetProperty(
-        &it, prop_value, STRICT, Object::CERTAINLY_NOT_STORE_FROM_KEYED);
-    if (result.IsNothing()) return result;
-    if (stable && call_to_js) stable = from->map() == *map;
-  }
-
-  return Just(true);
-}
-
-}  // namespace
-
-// ES6 19.1.2.1 Object.assign
-BUILTIN(ObjectAssign) {
-  HandleScope scope(isolate);
-  Handle<Object> target = args.atOrUndefined(isolate, 1);
-
-  // 1. Let to be ? ToObject(target).
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, target,
-                                     Object::ToObject(isolate, target));
-  Handle<JSReceiver> to = Handle<JSReceiver>::cast(target);
-  // 2. If only one argument was passed, return to.
-  if (args.length() == 2) return *to;
-  // 3. Let sources be the List of argument values starting with the
-  //    second argument.
-  // 4. For each element nextSource of sources, in ascending index order,
-  for (int i = 2; i < args.length(); ++i) {
-    Handle<Object> next_source = args.at<Object>(i);
-    Maybe<bool> fast_assign = FastAssign(to, next_source);
-    if (fast_assign.IsNothing()) return isolate->heap()->exception();
-    if (fast_assign.FromJust()) continue;
-    // 4a. If nextSource is undefined or null, let keys be an empty List.
-    // 4b. Else,
-    // 4b i. Let from be ToObject(nextSource).
-    // Only non-empty strings and JSReceivers have enumerable properties.
-    Handle<JSReceiver> from =
-        Object::ToObject(isolate, next_source).ToHandleChecked();
-    // 4b ii. Let keys be ? from.[[OwnPropertyKeys]]().
-    Handle<FixedArray> keys;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, keys, KeyAccumulator::GetKeys(
-                           from, KeyCollectionMode::kOwnOnly, ALL_PROPERTIES,
-                           GetKeysConversion::kKeepNumbers));
-    // 4c. Repeat for each element nextKey of keys in List order,
-    for (int j = 0; j < keys->length(); ++j) {
-      Handle<Object> next_key(keys->get(j), isolate);
-      // 4c i. Let desc be ? from.[[GetOwnProperty]](nextKey).
-      PropertyDescriptor desc;
-      Maybe<bool> found =
-          JSReceiver::GetOwnPropertyDescriptor(isolate, from, next_key, &desc);
-      if (found.IsNothing()) return isolate->heap()->exception();
-      // 4c ii. If desc is not undefined and desc.[[Enumerable]] is true, then
-      if (found.FromJust() && desc.enumerable()) {
-        // 4c ii 1. Let propValue be ? Get(from, nextKey).
-        Handle<Object> prop_value;
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-            isolate, prop_value,
-            Runtime::GetObjectProperty(isolate, from, next_key));
-        // 4c ii 2. Let status be ? Set(to, nextKey, propValue, true).
-        Handle<Object> status;
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-            isolate, status, Runtime::SetObjectProperty(isolate, to, next_key,
-                                                        prop_value, STRICT));
-      }
-    }
-  }
-  // 5. Return to.
-  return *to;
-}
-
-
-// ES6 section 19.1.2.2 Object.create ( O [ , Properties ] )
-// TODO(verwaest): Support the common cases with precached map directly in
-// an Object.create stub.
-BUILTIN(ObjectCreate) {
-  HandleScope scope(isolate);
-  Handle<Object> prototype = args.atOrUndefined(isolate, 1);
-  if (!prototype->IsNull(isolate) && !prototype->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kProtoObjectOrNull, prototype));
-  }
-
-  // Generate the map with the specified {prototype} based on the Object
-  // function's initial map from the current native context.
-  // TODO(bmeurer): Use a dedicated cache for Object.create; think about
-  // slack tracking for Object.create.
-  Handle<Map> map(isolate->native_context()->object_function()->initial_map(),
-                  isolate);
-  if (map->prototype() != *prototype) {
-    if (prototype->IsNull(isolate)) {
-      map = isolate->object_with_null_prototype_map();
-    } else if (prototype->IsJSObject()) {
-      Handle<JSObject> js_prototype = Handle<JSObject>::cast(prototype);
-      if (!js_prototype->map()->is_prototype_map()) {
-        JSObject::OptimizeAsPrototype(js_prototype, FAST_PROTOTYPE);
-      }
-      Handle<PrototypeInfo> info =
-          Map::GetOrCreatePrototypeInfo(js_prototype, isolate);
-      // TODO(verwaest): Use inobject slack tracking for this map.
-      if (info->HasObjectCreateMap()) {
-        map = handle(info->ObjectCreateMap(), isolate);
-      } else {
-        map = Map::CopyInitialMap(map);
-        Map::SetPrototype(map, prototype, FAST_PROTOTYPE);
-        PrototypeInfo::SetObjectCreateMap(info, map);
-      }
-    } else {
-      map = Map::TransitionToPrototype(map, prototype, REGULAR_PROTOTYPE);
-    }
-  }
-
-  // Actually allocate the object.
-  Handle<JSObject> object = isolate->factory()->NewJSObjectFromMap(map);
-
-  // Define the properties if properties was specified and is not undefined.
-  Handle<Object> properties = args.atOrUndefined(isolate, 2);
-  if (!properties->IsUndefined(isolate)) {
-    RETURN_FAILURE_ON_EXCEPTION(
-        isolate, JSReceiver::DefineProperties(isolate, object, properties));
-  }
-
-  return *object;
-}
-
-// ES6 section 19.1.2.3 Object.defineProperties
-BUILTIN(ObjectDefineProperties) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  Handle<Object> target = args.at<Object>(1);
-  Handle<Object> properties = args.at<Object>(2);
-
-  RETURN_RESULT_OR_FAILURE(
-      isolate, JSReceiver::DefineProperties(isolate, target, properties));
-}
-
-// ES6 section 19.1.2.4 Object.defineProperty
-BUILTIN(ObjectDefineProperty) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(4, args.length());
-  Handle<Object> target = args.at<Object>(1);
-  Handle<Object> key = args.at<Object>(2);
-  Handle<Object> attributes = args.at<Object>(3);
-
-  return JSReceiver::DefineProperty(isolate, target, key, attributes);
-}
-
-namespace {
-
-template <AccessorComponent which_accessor>
-Object* ObjectDefineAccessor(Isolate* isolate, Handle<Object> object,
-                             Handle<Object> name, Handle<Object> accessor) {
-  // 1. Let O be ? ToObject(this value).
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
-                                     Object::ConvertReceiver(isolate, object));
-  // 2. If IsCallable(getter) is false, throw a TypeError exception.
-  if (!accessor->IsCallable()) {
-    MessageTemplate::Template message =
-        which_accessor == ACCESSOR_GETTER
-            ? MessageTemplate::kObjectGetterExpectingFunction
-            : MessageTemplate::kObjectSetterExpectingFunction;
-    THROW_NEW_ERROR_RETURN_FAILURE(isolate, NewTypeError(message));
-  }
-  // 3. Let desc be PropertyDescriptor{[[Get]]: getter, [[Enumerable]]: true,
-  //                                   [[Configurable]]: true}.
-  PropertyDescriptor desc;
-  if (which_accessor == ACCESSOR_GETTER) {
-    desc.set_get(accessor);
-  } else {
-    DCHECK(which_accessor == ACCESSOR_SETTER);
-    desc.set_set(accessor);
-  }
-  desc.set_enumerable(true);
-  desc.set_configurable(true);
-  // 4. Let key be ? ToPropertyKey(P).
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToPropertyKey(isolate, name));
-  // 5. Perform ? DefinePropertyOrThrow(O, key, desc).
-  // To preserve legacy behavior, we ignore errors silently rather than
-  // throwing an exception.
-  Maybe<bool> success = JSReceiver::DefineOwnProperty(
-      isolate, receiver, name, &desc, Object::DONT_THROW);
-  MAYBE_RETURN(success, isolate->heap()->exception());
-  if (!success.FromJust()) {
-    isolate->CountUsage(v8::Isolate::kDefineGetterOrSetterWouldThrow);
-  }
-  // 6. Return undefined.
-  return isolate->heap()->undefined_value();
-}
-
-Object* ObjectLookupAccessor(Isolate* isolate, Handle<Object> object,
-                             Handle<Object> key, AccessorComponent component) {
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, object,
-                                     Object::ConvertReceiver(isolate, object));
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, key,
-                                     Object::ToPropertyKey(isolate, key));
-  bool success = false;
-  LookupIterator it = LookupIterator::PropertyOrElement(
-      isolate, object, key, &success,
-      LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR);
-  DCHECK(success);
-
-  for (; it.IsFound(); it.Next()) {
-    switch (it.state()) {
-      case LookupIterator::INTERCEPTOR:
-      case LookupIterator::NOT_FOUND:
-      case LookupIterator::TRANSITION:
-        UNREACHABLE();
-
-      case LookupIterator::ACCESS_CHECK:
-        if (it.HasAccess()) continue;
-        isolate->ReportFailedAccessCheck(it.GetHolder<JSObject>());
-        RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
-        return isolate->heap()->undefined_value();
-
-      case LookupIterator::JSPROXY:
-        return isolate->heap()->undefined_value();
-
-      case LookupIterator::INTEGER_INDEXED_EXOTIC:
-        return isolate->heap()->undefined_value();
-      case LookupIterator::DATA:
-        continue;
-      case LookupIterator::ACCESSOR: {
-        Handle<Object> maybe_pair = it.GetAccessors();
-        if (maybe_pair->IsAccessorPair()) {
-          return *AccessorPair::GetComponent(
-              Handle<AccessorPair>::cast(maybe_pair), component);
-        }
-      }
-    }
-  }
-
-  return isolate->heap()->undefined_value();
-}
-
-}  // namespace
-
-// ES6 B.2.2.2 a.k.a.
-// https://tc39.github.io/ecma262/#sec-object.prototype.__defineGetter__
-BUILTIN(ObjectDefineGetter) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.at<Object>(0);  // Receiver.
-  Handle<Object> name = args.at<Object>(1);
-  Handle<Object> getter = args.at<Object>(2);
-  return ObjectDefineAccessor<ACCESSOR_GETTER>(isolate, object, name, getter);
-}
-
-// ES6 B.2.2.3 a.k.a.
-// https://tc39.github.io/ecma262/#sec-object.prototype.__defineSetter__
-BUILTIN(ObjectDefineSetter) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.at<Object>(0);  // Receiver.
-  Handle<Object> name = args.at<Object>(1);
-  Handle<Object> setter = args.at<Object>(2);
-  return ObjectDefineAccessor<ACCESSOR_SETTER>(isolate, object, name, setter);
-}
-
-// ES6 B.2.2.4 a.k.a.
-// https://tc39.github.io/ecma262/#sec-object.prototype.__lookupGetter__
-BUILTIN(ObjectLookupGetter) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.at<Object>(0);
-  Handle<Object> name = args.at<Object>(1);
-  return ObjectLookupAccessor(isolate, object, name, ACCESSOR_GETTER);
-}
-
-// ES6 B.2.2.5 a.k.a.
-// https://tc39.github.io/ecma262/#sec-object.prototype.__lookupSetter__
-BUILTIN(ObjectLookupSetter) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.at<Object>(0);
-  Handle<Object> name = args.at<Object>(1);
-  return ObjectLookupAccessor(isolate, object, name, ACCESSOR_SETTER);
-}
-
-// ES6 section 19.1.2.5 Object.freeze ( O )
-BUILTIN(ObjectFreeze) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  if (object->IsJSReceiver()) {
-    MAYBE_RETURN(JSReceiver::SetIntegrityLevel(Handle<JSReceiver>::cast(object),
-                                               FROZEN, Object::THROW_ON_ERROR),
-                 isolate->heap()->exception());
-  }
-  return *object;
-}
-
-
-// ES section 19.1.2.9 Object.getPrototypeOf ( O )
-BUILTIN(ObjectGetPrototypeOf) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, receiver, Object::ToObject(isolate, object));
-
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           JSReceiver::GetPrototype(isolate, receiver));
-}
-
-
-// ES6 section 19.1.2.6 Object.getOwnPropertyDescriptor ( O, P )
-BUILTIN(ObjectGetOwnPropertyDescriptor) {
-  HandleScope scope(isolate);
-  // 1. Let obj be ? ToObject(O).
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
-                                     Object::ToObject(isolate, object));
-  // 2. Let key be ? ToPropertyKey(P).
-  Handle<Object> property = args.atOrUndefined(isolate, 2);
-  Handle<Name> key;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, key,
-                                     Object::ToName(isolate, property));
-  // 3. Let desc be ? obj.[[GetOwnProperty]](key).
-  PropertyDescriptor desc;
-  Maybe<bool> found =
-      JSReceiver::GetOwnPropertyDescriptor(isolate, receiver, key, &desc);
-  MAYBE_RETURN(found, isolate->heap()->exception());
-  // 4. Return FromPropertyDescriptor(desc).
-  if (!found.FromJust()) return isolate->heap()->undefined_value();
-  return *desc.ToObject(isolate);
-}
-
-
-namespace {
-
-Object* GetOwnPropertyKeys(Isolate* isolate, BuiltinArguments args,
-                           PropertyFilter filter) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
-                                     Object::ToObject(isolate, object));
-  Handle<FixedArray> keys;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, keys,
-      KeyAccumulator::GetKeys(receiver, KeyCollectionMode::kOwnOnly, filter,
-                              GetKeysConversion::kConvertToString));
-  return *isolate->factory()->NewJSArrayWithElements(keys);
-}
-
-}  // namespace
-
-
-// ES6 section 19.1.2.7 Object.getOwnPropertyNames ( O )
-BUILTIN(ObjectGetOwnPropertyNames) {
-  return GetOwnPropertyKeys(isolate, args, SKIP_SYMBOLS);
-}
-
-
-// ES6 section 19.1.2.8 Object.getOwnPropertySymbols ( O )
-BUILTIN(ObjectGetOwnPropertySymbols) {
-  return GetOwnPropertyKeys(isolate, args, SKIP_STRINGS);
-}
-
-
-// ES#sec-object.is Object.is ( value1, value2 )
-BUILTIN(ObjectIs) {
-  SealHandleScope shs(isolate);
-  DCHECK_EQ(3, args.length());
-  Handle<Object> value1 = args.at<Object>(1);
-  Handle<Object> value2 = args.at<Object>(2);
-  return isolate->heap()->ToBoolean(value1->SameValue(*value2));
-}
-
-
-// ES6 section 19.1.2.11 Object.isExtensible ( O )
-BUILTIN(ObjectIsExtensible) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Maybe<bool> result =
-      object->IsJSReceiver()
-          ? JSReceiver::IsExtensible(Handle<JSReceiver>::cast(object))
-          : Just(false);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return isolate->heap()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 19.1.2.12 Object.isFrozen ( O )
-BUILTIN(ObjectIsFrozen) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Maybe<bool> result = object->IsJSReceiver()
-                           ? JSReceiver::TestIntegrityLevel(
-                                 Handle<JSReceiver>::cast(object), FROZEN)
-                           : Just(true);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return isolate->heap()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 19.1.2.13 Object.isSealed ( O )
-BUILTIN(ObjectIsSealed) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Maybe<bool> result = object->IsJSReceiver()
-                           ? JSReceiver::TestIntegrityLevel(
-                                 Handle<JSReceiver>::cast(object), SEALED)
-                           : Just(true);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return isolate->heap()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 19.1.2.14 Object.keys ( O )
-BUILTIN(ObjectKeys) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
-                                     Object::ToObject(isolate, object));
-
-  Handle<FixedArray> keys;
-  int enum_length = receiver->map()->EnumLength();
-  if (enum_length != kInvalidEnumCacheSentinel &&
-      JSObject::cast(*receiver)->elements() ==
-          isolate->heap()->empty_fixed_array()) {
-    DCHECK(receiver->IsJSObject());
-    DCHECK(!JSObject::cast(*receiver)->HasNamedInterceptor());
-    DCHECK(!JSObject::cast(*receiver)->IsAccessCheckNeeded());
-    DCHECK(!receiver->map()->has_hidden_prototype());
-    DCHECK(JSObject::cast(*receiver)->HasFastProperties());
-    if (enum_length == 0) {
-      keys = isolate->factory()->empty_fixed_array();
-    } else {
-      Handle<FixedArray> cache(
-          receiver->map()->instance_descriptors()->GetEnumCache());
-      keys = isolate->factory()->CopyFixedArrayUpTo(cache, enum_length);
-    }
-  } else {
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, keys,
-        KeyAccumulator::GetKeys(receiver, KeyCollectionMode::kOwnOnly,
-                                ENUMERABLE_STRINGS,
-                                GetKeysConversion::kConvertToString));
-  }
-  return *isolate->factory()->NewJSArrayWithElements(keys, FAST_ELEMENTS);
-}
-
-BUILTIN(ObjectValues) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
-                                     Object::ToObject(isolate, object));
-  Handle<FixedArray> values;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, values, JSReceiver::GetOwnValues(receiver, ENUMERABLE_STRINGS));
-  return *isolate->factory()->NewJSArrayWithElements(values);
-}
-
-
-BUILTIN(ObjectEntries) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
-                                     Object::ToObject(isolate, object));
-  Handle<FixedArray> entries;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, entries,
-      JSReceiver::GetOwnEntries(receiver, ENUMERABLE_STRINGS));
-  return *isolate->factory()->NewJSArrayWithElements(entries);
-}
-
-BUILTIN(ObjectGetOwnPropertyDescriptors) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-
-  Handle<JSReceiver> receiver;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver,
-                                     Object::ToObject(isolate, object));
-
-  Handle<FixedArray> keys;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, keys, KeyAccumulator::GetKeys(
-                         receiver, KeyCollectionMode::kOwnOnly, ALL_PROPERTIES,
-                         GetKeysConversion::kConvertToString));
-
-  Handle<JSObject> descriptors =
-      isolate->factory()->NewJSObject(isolate->object_function());
-
-  for (int i = 0; i < keys->length(); ++i) {
-    Handle<Name> key = Handle<Name>::cast(FixedArray::get(*keys, i, isolate));
-    PropertyDescriptor descriptor;
-    Maybe<bool> did_get_descriptor = JSReceiver::GetOwnPropertyDescriptor(
-        isolate, receiver, key, &descriptor);
-    MAYBE_RETURN(did_get_descriptor, isolate->heap()->exception());
-
-    if (!did_get_descriptor.FromJust()) continue;
-    Handle<Object> from_descriptor = descriptor.ToObject(isolate);
-
-    LookupIterator it = LookupIterator::PropertyOrElement(
-        isolate, descriptors, key, descriptors, LookupIterator::OWN);
-    Maybe<bool> success = JSReceiver::CreateDataProperty(&it, from_descriptor,
-                                                         Object::DONT_THROW);
-    CHECK(success.FromJust());
-  }
-
-  return *descriptors;
-}
-
-// ES6 section 19.1.2.15 Object.preventExtensions ( O )
-BUILTIN(ObjectPreventExtensions) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  if (object->IsJSReceiver()) {
-    MAYBE_RETURN(JSReceiver::PreventExtensions(Handle<JSReceiver>::cast(object),
-                                               Object::THROW_ON_ERROR),
-                 isolate->heap()->exception());
-  }
-  return *object;
-}
-
-
-// ES6 section 19.1.2.17 Object.seal ( O )
-BUILTIN(ObjectSeal) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  if (object->IsJSReceiver()) {
-    MAYBE_RETURN(JSReceiver::SetIntegrityLevel(Handle<JSReceiver>::cast(object),
-                                               SEALED, Object::THROW_ON_ERROR),
-                 isolate->heap()->exception());
-  }
-  return *object;
-}
-
-// ES6 section 18.2.6.2 decodeURI (encodedURI)
-BUILTIN(GlobalDecodeURI) {
-  HandleScope scope(isolate);
-  Handle<String> encoded_uri;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, encoded_uri,
-      Object::ToString(isolate, args.atOrUndefined(isolate, 1)));
-
-  RETURN_RESULT_OR_FAILURE(isolate, Uri::DecodeUri(isolate, encoded_uri));
-}
-
-// ES6 section 18.2.6.3 decodeURIComponent (encodedURIComponent)
-BUILTIN(GlobalDecodeURIComponent) {
-  HandleScope scope(isolate);
-  Handle<String> encoded_uri_component;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, encoded_uri_component,
-      Object::ToString(isolate, args.atOrUndefined(isolate, 1)));
-
-  RETURN_RESULT_OR_FAILURE(
-      isolate, Uri::DecodeUriComponent(isolate, encoded_uri_component));
-}
-
-// ES6 section 18.2.6.4 encodeURI (uri)
-BUILTIN(GlobalEncodeURI) {
-  HandleScope scope(isolate);
-  Handle<String> uri;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, uri, Object::ToString(isolate, args.atOrUndefined(isolate, 1)));
-
-  RETURN_RESULT_OR_FAILURE(isolate, Uri::EncodeUri(isolate, uri));
-}
-
-// ES6 section 18.2.6.5 encodeURIComponenet (uriComponent)
-BUILTIN(GlobalEncodeURIComponent) {
-  HandleScope scope(isolate);
-  Handle<String> uri_component;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, uri_component,
-      Object::ToString(isolate, args.atOrUndefined(isolate, 1)));
-
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           Uri::EncodeUriComponent(isolate, uri_component));
-}
-
-// ES6 section B.2.1.1 escape (string)
-BUILTIN(GlobalEscape) {
-  HandleScope scope(isolate);
-  Handle<String> string;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, string,
-      Object::ToString(isolate, args.atOrUndefined(isolate, 1)));
-
-  RETURN_RESULT_OR_FAILURE(isolate, Uri::Escape(isolate, string));
-}
-
-// ES6 section B.2.1.2 unescape (string)
-BUILTIN(GlobalUnescape) {
-  HandleScope scope(isolate);
-  Handle<String> string;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, string,
-      Object::ToString(isolate, args.atOrUndefined(isolate, 1)));
-
-  RETURN_RESULT_OR_FAILURE(isolate, Uri::Unescape(isolate, string));
-}
-
-namespace {
-
-bool CodeGenerationFromStringsAllowed(Isolate* isolate,
-                                      Handle<Context> context) {
-  DCHECK(context->allow_code_gen_from_strings()->IsFalse(isolate));
-  // Check with callback if set.
-  AllowCodeGenerationFromStringsCallback callback =
-      isolate->allow_code_gen_callback();
-  if (callback == NULL) {
-    // No callback set and code generation disallowed.
-    return false;
-  } else {
-    // Callback set. Let it decide if code generation is allowed.
-    VMState<EXTERNAL> state(isolate);
-    return callback(v8::Utils::ToLocal(context));
-  }
-}
-
-
-MaybeHandle<JSFunction> CompileString(Handle<Context> context,
-                                      Handle<String> source,
-                                      ParseRestriction restriction) {
-  Isolate* const isolate = context->GetIsolate();
-  Handle<Context> native_context(context->native_context(), isolate);
-
-  // Check if native context allows code generation from
-  // strings. Throw an exception if it doesn't.
-  if (native_context->allow_code_gen_from_strings()->IsFalse(isolate) &&
-      !CodeGenerationFromStringsAllowed(isolate, native_context)) {
-    Handle<Object> error_message =
-        native_context->ErrorMessageForCodeGenerationFromStrings();
-    THROW_NEW_ERROR(isolate, NewEvalError(MessageTemplate::kCodeGenFromStrings,
-                                          error_message),
-                    JSFunction);
-  }
-
-  // Compile source string in the native context.
-  int eval_scope_position = 0;
-  int eval_position = kNoSourcePosition;
-  Handle<SharedFunctionInfo> outer_info(native_context->closure()->shared());
-  return Compiler::GetFunctionFromEval(source, outer_info, native_context,
-                                       SLOPPY, restriction, eval_scope_position,
-                                       eval_position);
-}
-
-}  // namespace
-
-
-// ES6 section 18.2.1 eval (x)
-BUILTIN(GlobalEval) {
-  HandleScope scope(isolate);
-  Handle<Object> x = args.atOrUndefined(isolate, 1);
-  Handle<JSFunction> target = args.target<JSFunction>();
-  Handle<JSObject> target_global_proxy(target->global_proxy(), isolate);
-  if (!x->IsString()) return *x;
-  Handle<JSFunction> function;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, function,
-      CompileString(handle(target->native_context(), isolate),
-                    Handle<String>::cast(x), NO_PARSE_RESTRICTION));
-  RETURN_RESULT_OR_FAILURE(
-      isolate,
-      Execution::Call(isolate, function, target_global_proxy, 0, nullptr));
-}
-
-// ES6 section 24.3.1 JSON.parse.
-BUILTIN(JsonParse) {
-  HandleScope scope(isolate);
-  Handle<Object> source = args.atOrUndefined(isolate, 1);
-  Handle<Object> reviver = args.atOrUndefined(isolate, 2);
-  Handle<String> string;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, string,
-                                     Object::ToString(isolate, source));
-  string = String::Flatten(string);
-  RETURN_RESULT_OR_FAILURE(
-      isolate, string->IsSeqOneByteString()
-                   ? JsonParser<true>::Parse(isolate, string, reviver)
-                   : JsonParser<false>::Parse(isolate, string, reviver));
-}
-
-// ES6 section 24.3.2 JSON.stringify.
-BUILTIN(JsonStringify) {
-  HandleScope scope(isolate);
-  JsonStringifier stringifier(isolate);
-  Handle<Object> object = args.atOrUndefined(isolate, 1);
-  Handle<Object> replacer = args.atOrUndefined(isolate, 2);
-  Handle<Object> indent = args.atOrUndefined(isolate, 3);
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           stringifier.Stringify(object, replacer, indent));
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 20.1 Number Objects
-
-// ES6 section 20.1.3.2 Number.prototype.toExponential ( fractionDigits )
-BUILTIN(NumberPrototypeToExponential) {
-  HandleScope scope(isolate);
-  Handle<Object> value = args.at<Object>(0);
-  Handle<Object> fraction_digits = args.atOrUndefined(isolate, 1);
-
-  // Unwrap the receiver {value}.
-  if (value->IsJSValue()) {
-    value = handle(Handle<JSValue>::cast(value)->value(), isolate);
-  }
-  if (!value->IsNumber()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kNotGeneric,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Number.prototype.toExponential")));
-  }
-  double const value_number = value->Number();
-
-  // Convert the {fraction_digits} to an integer first.
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, fraction_digits, Object::ToInteger(isolate, fraction_digits));
-  double const fraction_digits_number = fraction_digits->Number();
-
-  if (std::isnan(value_number)) return isolate->heap()->nan_string();
-  if (std::isinf(value_number)) {
-    return (value_number < 0.0) ? isolate->heap()->minus_infinity_string()
-                                : isolate->heap()->infinity_string();
-  }
-  if (fraction_digits_number < 0.0 || fraction_digits_number > 20.0) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kNumberFormatRange,
-                               isolate->factory()->NewStringFromAsciiChecked(
-                                   "toExponential()")));
-  }
-  int const f = args.atOrUndefined(isolate, 1)->IsUndefined(isolate)
-                    ? -1
-                    : static_cast<int>(fraction_digits_number);
-  char* const str = DoubleToExponentialCString(value_number, f);
-  Handle<String> result = isolate->factory()->NewStringFromAsciiChecked(str);
-  DeleteArray(str);
-  return *result;
-}
-
-// ES6 section 20.1.3.3 Number.prototype.toFixed ( fractionDigits )
-BUILTIN(NumberPrototypeToFixed) {
-  HandleScope scope(isolate);
-  Handle<Object> value = args.at<Object>(0);
-  Handle<Object> fraction_digits = args.atOrUndefined(isolate, 1);
-
-  // Unwrap the receiver {value}.
-  if (value->IsJSValue()) {
-    value = handle(Handle<JSValue>::cast(value)->value(), isolate);
-  }
-  if (!value->IsNumber()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kNotGeneric,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Number.prototype.toFixed")));
-  }
-  double const value_number = value->Number();
-
-  // Convert the {fraction_digits} to an integer first.
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, fraction_digits, Object::ToInteger(isolate, fraction_digits));
-  double const fraction_digits_number = fraction_digits->Number();
-
-  // Check if the {fraction_digits} are in the supported range.
-  if (fraction_digits_number < 0.0 || fraction_digits_number > 20.0) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kNumberFormatRange,
-                               isolate->factory()->NewStringFromAsciiChecked(
-                                   "toFixed() digits")));
-  }
-
-  if (std::isnan(value_number)) return isolate->heap()->nan_string();
-  if (std::isinf(value_number)) {
-    return (value_number < 0.0) ? isolate->heap()->minus_infinity_string()
-                                : isolate->heap()->infinity_string();
-  }
-  char* const str = DoubleToFixedCString(
-      value_number, static_cast<int>(fraction_digits_number));
-  Handle<String> result = isolate->factory()->NewStringFromAsciiChecked(str);
-  DeleteArray(str);
-  return *result;
-}
-
-// ES6 section 20.1.3.4 Number.prototype.toLocaleString ( [ r1 [ , r2 ] ] )
-BUILTIN(NumberPrototypeToLocaleString) {
-  HandleScope scope(isolate);
-  Handle<Object> value = args.at<Object>(0);
-
-  // Unwrap the receiver {value}.
-  if (value->IsJSValue()) {
-    value = handle(Handle<JSValue>::cast(value)->value(), isolate);
-  }
-  if (!value->IsNumber()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kNotGeneric,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Number.prototype.toLocaleString")));
-  }
-
-  // Turn the {value} into a String.
-  return *isolate->factory()->NumberToString(value);
-}
-
-// ES6 section 20.1.3.5 Number.prototype.toPrecision ( precision )
-BUILTIN(NumberPrototypeToPrecision) {
-  HandleScope scope(isolate);
-  Handle<Object> value = args.at<Object>(0);
-  Handle<Object> precision = args.atOrUndefined(isolate, 1);
-
-  // Unwrap the receiver {value}.
-  if (value->IsJSValue()) {
-    value = handle(Handle<JSValue>::cast(value)->value(), isolate);
-  }
-  if (!value->IsNumber()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kNotGeneric,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Number.prototype.toPrecision")));
-  }
-  double const value_number = value->Number();
-
-  // If no {precision} was specified, just return ToString of {value}.
-  if (precision->IsUndefined(isolate)) {
-    return *isolate->factory()->NumberToString(value);
-  }
-
-  // Convert the {precision} to an integer first.
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, precision,
-                                     Object::ToInteger(isolate, precision));
-  double const precision_number = precision->Number();
-
-  if (std::isnan(value_number)) return isolate->heap()->nan_string();
-  if (std::isinf(value_number)) {
-    return (value_number < 0.0) ? isolate->heap()->minus_infinity_string()
-                                : isolate->heap()->infinity_string();
-  }
-  if (precision_number < 1.0 || precision_number > 21.0) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kToPrecisionFormatRange));
-  }
-  char* const str = DoubleToPrecisionCString(
-      value_number, static_cast<int>(precision_number));
-  Handle<String> result = isolate->factory()->NewStringFromAsciiChecked(str);
-  DeleteArray(str);
-  return *result;
-}
-
-// ES6 section 20.1.3.6 Number.prototype.toString ( [ radix ] )
-BUILTIN(NumberPrototypeToString) {
-  HandleScope scope(isolate);
-  Handle<Object> value = args.at<Object>(0);
-  Handle<Object> radix = args.atOrUndefined(isolate, 1);
-
-  // Unwrap the receiver {value}.
-  if (value->IsJSValue()) {
-    value = handle(Handle<JSValue>::cast(value)->value(), isolate);
-  }
-  if (!value->IsNumber()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kNotGeneric,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Number.prototype.toString")));
-  }
-  double const value_number = value->Number();
-
-  // If no {radix} was specified, just return ToString of {value}.
-  if (radix->IsUndefined(isolate)) {
-    return *isolate->factory()->NumberToString(value);
-  }
-
-  // Convert the {radix} to an integer first.
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, radix,
-                                     Object::ToInteger(isolate, radix));
-  double const radix_number = radix->Number();
-
-  // If {radix} is 10, just return ToString of {value}.
-  if (radix_number == 10.0) return *isolate->factory()->NumberToString(value);
-
-  // Make sure the {radix} is within the valid range.
-  if (radix_number < 2.0 || radix_number > 36.0) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kToRadixFormatRange));
-  }
-
-  // Fast case where the result is a one character string.
-  if (IsUint32Double(value_number) && value_number < radix_number) {
-    // Character array used for conversion.
-    static const char kCharTable[] = "0123456789abcdefghijklmnopqrstuvwxyz";
-    return *isolate->factory()->LookupSingleCharacterStringFromCode(
-        kCharTable[static_cast<uint32_t>(value_number)]);
-  }
-
-  // Slow case.
-  if (std::isnan(value_number)) return isolate->heap()->nan_string();
-  if (std::isinf(value_number)) {
-    return (value_number < 0.0) ? isolate->heap()->minus_infinity_string()
-                                : isolate->heap()->infinity_string();
-  }
-  char* const str =
-      DoubleToRadixCString(value_number, static_cast<int>(radix_number));
-  Handle<String> result = isolate->factory()->NewStringFromAsciiChecked(str);
-  DeleteArray(str);
-  return *result;
-}
-
-// ES6 section 20.1.3.7 Number.prototype.valueOf ( )
-void Builtins::Generate_NumberPrototypeValueOf(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  Node* result = assembler->ToThisValue(
-      context, receiver, PrimitiveType::kNumber, "Number.prototype.valueOf");
-  assembler->Return(result);
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 20.2.2 Function Properties of the Math Object
-
-// ES6 section - 20.2.2.1 Math.abs ( x )
-void Builtins::Generate_MathAbs(CodeStubAssembler* assembler) {
-  using compiler::Node;
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Abs(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.2 Math.acos ( x )
-void Builtins::Generate_MathAcos(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Acos(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.3 Math.acosh ( x )
-void Builtins::Generate_MathAcosh(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Acosh(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.4 Math.asin ( x )
-void Builtins::Generate_MathAsin(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Asin(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.5 Math.asinh ( x )
-void Builtins::Generate_MathAsinh(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Asinh(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.6 Math.atan ( x )
-void Builtins::Generate_MathAtan(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Atan(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.7 Math.atanh ( x )
-void Builtins::Generate_MathAtanh(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Atanh(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.8 Math.atan2 ( y, x )
-void Builtins::Generate_MathAtan2(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* y = assembler->Parameter(1);
-  Node* x = assembler->Parameter(2);
-  Node* context = assembler->Parameter(5);
-  Node* y_value = assembler->TruncateTaggedToFloat64(context, y);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Atan2(y_value, x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-namespace {
-
-void Generate_MathRoundingOperation(
-    CodeStubAssembler* assembler,
-    compiler::Node* (CodeStubAssembler::*float64op)(compiler::Node*)) {
-  typedef CodeStubAssembler::Label Label;
-  typedef compiler::Node Node;
-  typedef CodeStubAssembler::Variable Variable;
-
-  Node* context = assembler->Parameter(4);
-
-  // We might need to loop once for ToNumber conversion.
-  Variable var_x(assembler, MachineRepresentation::kTagged);
-  Label loop(assembler, &var_x);
-  var_x.Bind(assembler->Parameter(1));
-  assembler->Goto(&loop);
-  assembler->Bind(&loop);
-  {
-    // Load the current {x} value.
-    Node* x = var_x.value();
-
-    // Check if {x} is a Smi or a HeapObject.
-    Label if_xissmi(assembler), if_xisnotsmi(assembler);
-    assembler->Branch(assembler->WordIsSmi(x), &if_xissmi, &if_xisnotsmi);
-
-    assembler->Bind(&if_xissmi);
-    {
-      // Nothing to do when {x} is a Smi.
-      assembler->Return(x);
-    }
-
-    assembler->Bind(&if_xisnotsmi);
-    {
-      // Check if {x} is a HeapNumber.
-      Label if_xisheapnumber(assembler),
-          if_xisnotheapnumber(assembler, Label::kDeferred);
-      assembler->Branch(
-          assembler->WordEqual(assembler->LoadMap(x),
-                               assembler->HeapNumberMapConstant()),
-          &if_xisheapnumber, &if_xisnotheapnumber);
-
-      assembler->Bind(&if_xisheapnumber);
-      {
-        Node* x_value = assembler->LoadHeapNumberValue(x);
-        Node* value = (assembler->*float64op)(x_value);
-        Node* result = assembler->ChangeFloat64ToTagged(value);
-        assembler->Return(result);
-      }
-
-      assembler->Bind(&if_xisnotheapnumber);
-      {
-        // Need to convert {x} to a Number first.
-        Callable callable =
-            CodeFactory::NonNumberToNumber(assembler->isolate());
-        var_x.Bind(assembler->CallStub(callable, context, x));
-        assembler->Goto(&loop);
-      }
-    }
-  }
-}
-
-}  // namespace
-
-// ES6 section 20.2.2.10 Math.ceil ( x )
-void Builtins::Generate_MathCeil(CodeStubAssembler* assembler) {
-  Generate_MathRoundingOperation(assembler, &CodeStubAssembler::Float64Ceil);
-}
-
-// ES6 section 20.2.2.9 Math.cbrt ( x )
-void Builtins::Generate_MathCbrt(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Cbrt(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.11 Math.clz32 ( x )
-void Builtins::Generate_MathClz32(CodeStubAssembler* assembler) {
-  typedef CodeStubAssembler::Label Label;
-  typedef compiler::Node Node;
-  typedef CodeStubAssembler::Variable Variable;
-
-  Node* context = assembler->Parameter(4);
-
-  // Shared entry point for the clz32 operation.
-  Variable var_clz32_x(assembler, MachineRepresentation::kWord32);
-  Label do_clz32(assembler);
-
-  // We might need to loop once for ToNumber conversion.
-  Variable var_x(assembler, MachineRepresentation::kTagged);
-  Label loop(assembler, &var_x);
-  var_x.Bind(assembler->Parameter(1));
-  assembler->Goto(&loop);
-  assembler->Bind(&loop);
-  {
-    // Load the current {x} value.
-    Node* x = var_x.value();
-
-    // Check if {x} is a Smi or a HeapObject.
-    Label if_xissmi(assembler), if_xisnotsmi(assembler);
-    assembler->Branch(assembler->WordIsSmi(x), &if_xissmi, &if_xisnotsmi);
-
-    assembler->Bind(&if_xissmi);
-    {
-      var_clz32_x.Bind(assembler->SmiToWord32(x));
-      assembler->Goto(&do_clz32);
-    }
-
-    assembler->Bind(&if_xisnotsmi);
-    {
-      // Check if {x} is a HeapNumber.
-      Label if_xisheapnumber(assembler),
-          if_xisnotheapnumber(assembler, Label::kDeferred);
-      assembler->Branch(
-          assembler->WordEqual(assembler->LoadMap(x),
-                               assembler->HeapNumberMapConstant()),
-          &if_xisheapnumber, &if_xisnotheapnumber);
-
-      assembler->Bind(&if_xisheapnumber);
-      {
-        var_clz32_x.Bind(assembler->TruncateHeapNumberValueToWord32(x));
-        assembler->Goto(&do_clz32);
-      }
-
-      assembler->Bind(&if_xisnotheapnumber);
-      {
-        // Need to convert {x} to a Number first.
-        Callable callable =
-            CodeFactory::NonNumberToNumber(assembler->isolate());
-        var_x.Bind(assembler->CallStub(callable, context, x));
-        assembler->Goto(&loop);
-      }
-    }
-  }
-
-  assembler->Bind(&do_clz32);
-  {
-    Node* x_value = var_clz32_x.value();
-    Node* value = assembler->Word32Clz(x_value);
-    Node* result = assembler->ChangeInt32ToTagged(value);
-    assembler->Return(result);
-  }
-}
-
-// ES6 section 20.2.2.12 Math.cos ( x )
-void Builtins::Generate_MathCos(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Cos(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.13 Math.cosh ( x )
-void Builtins::Generate_MathCosh(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Cosh(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.14 Math.exp ( x )
-void Builtins::Generate_MathExp(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Exp(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.16 Math.floor ( x )
-void Builtins::Generate_MathFloor(CodeStubAssembler* assembler) {
-  Generate_MathRoundingOperation(assembler, &CodeStubAssembler::Float64Floor);
-}
-
-// ES6 section 20.2.2.17 Math.fround ( x )
-void Builtins::Generate_MathFround(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value32 = assembler->TruncateFloat64ToFloat32(x_value);
-  Node* value = assembler->ChangeFloat32ToFloat64(value32);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.18 Math.hypot ( value1, value2, ...values )
-BUILTIN(MathHypot) {
-  HandleScope scope(isolate);
-  int const length = args.length() - 1;
-  if (length == 0) return Smi::FromInt(0);
-  DCHECK_LT(0, length);
-  double max = 0;
-  bool one_arg_is_nan = false;
-  List<double> abs_values(length);
-  for (int i = 0; i < length; i++) {
-    Handle<Object> x = args.at<Object>(i + 1);
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, x, Object::ToNumber(x));
-    double abs_value = std::abs(x->Number());
-
-    if (std::isnan(abs_value)) {
-      one_arg_is_nan = true;
-    } else {
-      abs_values.Add(abs_value);
-      if (max < abs_value) {
-        max = abs_value;
-      }
-    }
-  }
-
-  if (max == V8_INFINITY) {
-    return *isolate->factory()->NewNumber(V8_INFINITY);
-  }
-
-  if (one_arg_is_nan) {
-    return *isolate->factory()->nan_value();
-  }
-
-  if (max == 0) {
-    return Smi::FromInt(0);
-  }
-  DCHECK_GT(max, 0);
-
-  // Kahan summation to avoid rounding errors.
-  // Normalize the numbers to the largest one to avoid overflow.
-  double sum = 0;
-  double compensation = 0;
-  for (int i = 0; i < length; i++) {
-    double n = abs_values.at(i) / max;
-    double summand = n * n - compensation;
-    double preliminary = sum + summand;
-    compensation = (preliminary - sum) - summand;
-    sum = preliminary;
-  }
-
-  return *isolate->factory()->NewNumber(std::sqrt(sum) * max);
-}
-
-// ES6 section 20.2.2.19 Math.imul ( x, y )
-void Builtins::Generate_MathImul(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* y = assembler->Parameter(2);
-  Node* context = assembler->Parameter(5);
-  Node* x_value = assembler->TruncateTaggedToWord32(context, x);
-  Node* y_value = assembler->TruncateTaggedToWord32(context, y);
-  Node* value = assembler->Int32Mul(x_value, y_value);
-  Node* result = assembler->ChangeInt32ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.20 Math.log ( x )
-void Builtins::Generate_MathLog(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Log(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.21 Math.log1p ( x )
-void Builtins::Generate_MathLog1p(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Log1p(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.22 Math.log10 ( x )
-void Builtins::Generate_MathLog10(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Log10(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.23 Math.log2 ( x )
-void Builtins::Generate_MathLog2(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Log2(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.15 Math.expm1 ( x )
-void Builtins::Generate_MathExpm1(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Expm1(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.26 Math.pow ( x, y )
-void Builtins::Generate_MathPow(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* y = assembler->Parameter(2);
-  Node* context = assembler->Parameter(5);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* y_value = assembler->TruncateTaggedToFloat64(context, y);
-  Node* value = assembler->Float64Pow(x_value, y_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.28 Math.round ( x )
-void Builtins::Generate_MathRound(CodeStubAssembler* assembler) {
-  Generate_MathRoundingOperation(assembler, &CodeStubAssembler::Float64Round);
-}
-
-// ES6 section 20.2.2.29 Math.sign ( x )
-void Builtins::Generate_MathSign(CodeStubAssembler* assembler) {
-  typedef CodeStubAssembler::Label Label;
-  using compiler::Node;
-
-  // Convert the {x} value to a Number.
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-
-  // Return -1 if {x} is negative, 1 if {x} is positive, or {x} itself.
-  Label if_xisnegative(assembler), if_xispositive(assembler);
-  assembler->GotoIf(
-      assembler->Float64LessThan(x_value, assembler->Float64Constant(0.0)),
-      &if_xisnegative);
-  assembler->GotoIf(
-      assembler->Float64LessThan(assembler->Float64Constant(0.0), x_value),
-      &if_xispositive);
-  assembler->Return(assembler->ChangeFloat64ToTagged(x_value));
-
-  assembler->Bind(&if_xisnegative);
-  assembler->Return(assembler->SmiConstant(Smi::FromInt(-1)));
-
-  assembler->Bind(&if_xispositive);
-  assembler->Return(assembler->SmiConstant(Smi::FromInt(1)));
-}
-
-// ES6 section 20.2.2.30 Math.sin ( x )
-void Builtins::Generate_MathSin(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Sin(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.31 Math.sinh ( x )
-void Builtins::Generate_MathSinh(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Sinh(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.32 Math.sqrt ( x )
-void Builtins::Generate_MathSqrt(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Sqrt(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.33 Math.tan ( x )
-void Builtins::Generate_MathTan(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Tan(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.34 Math.tanh ( x )
-void Builtins::Generate_MathTanh(CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* x = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* x_value = assembler->TruncateTaggedToFloat64(context, x);
-  Node* value = assembler->Float64Tanh(x_value);
-  Node* result = assembler->ChangeFloat64ToTagged(value);
-  assembler->Return(result);
-}
-
-// ES6 section 20.2.2.35 Math.trunc ( x )
-void Builtins::Generate_MathTrunc(CodeStubAssembler* assembler) {
-  Generate_MathRoundingOperation(assembler, &CodeStubAssembler::Float64Trunc);
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 19.2 Function Objects
-
-// ES6 section 19.2.3.6 Function.prototype [ @@hasInstance ] ( V )
-void Builtins::Generate_FunctionPrototypeHasInstance(
-    CodeStubAssembler* assembler) {
-  using compiler::Node;
-
-  Node* f = assembler->Parameter(0);
-  Node* v = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* result = assembler->OrdinaryHasInstance(context, f, v);
-  assembler->Return(result);
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 25.3 Generator Objects
-
-namespace {
-
-void Generate_GeneratorPrototypeResume(
-    CodeStubAssembler* assembler, JSGeneratorObject::ResumeMode resume_mode,
-    char const* const method_name) {
-  typedef CodeStubAssembler::Label Label;
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* value = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-  Node* closed = assembler->SmiConstant(
-      Smi::FromInt(JSGeneratorObject::kGeneratorClosed));
-
-  // Check if the {receiver} is actually a JSGeneratorObject.
-  Label if_receiverisincompatible(assembler, Label::kDeferred);
-  assembler->GotoIf(assembler->WordIsSmi(receiver), &if_receiverisincompatible);
-  Node* receiver_instance_type = assembler->LoadInstanceType(receiver);
-  assembler->GotoUnless(assembler->Word32Equal(
-                            receiver_instance_type,
-                            assembler->Int32Constant(JS_GENERATOR_OBJECT_TYPE)),
-                        &if_receiverisincompatible);
-
-  // Check if the {receiver} is running or already closed.
-  Node* receiver_continuation = assembler->LoadObjectField(
-      receiver, JSGeneratorObject::kContinuationOffset);
-  Label if_receiverisclosed(assembler, Label::kDeferred),
-      if_receiverisrunning(assembler, Label::kDeferred);
-  assembler->GotoIf(assembler->SmiEqual(receiver_continuation, closed),
-                    &if_receiverisclosed);
-  DCHECK_LT(JSGeneratorObject::kGeneratorExecuting,
-            JSGeneratorObject::kGeneratorClosed);
-  assembler->GotoIf(assembler->SmiLessThan(receiver_continuation, closed),
-                    &if_receiverisrunning);
-
-  // Resume the {receiver} using our trampoline.
-  Node* result = assembler->CallStub(
-      CodeFactory::ResumeGenerator(assembler->isolate()), context, value,
-      receiver, assembler->SmiConstant(Smi::FromInt(resume_mode)));
-  assembler->Return(result);
-
-  assembler->Bind(&if_receiverisincompatible);
-  {
-    // The {receiver} is not a valid JSGeneratorObject.
-    Node* result = assembler->CallRuntime(
-        Runtime::kThrowIncompatibleMethodReceiver, context,
-        assembler->HeapConstant(assembler->factory()->NewStringFromAsciiChecked(
-            method_name, TENURED)),
-        receiver);
-    assembler->Return(result);  // Never reached.
-  }
-
-  assembler->Bind(&if_receiverisclosed);
-  {
-    // The {receiver} is closed already.
-    Node* result = nullptr;
-    switch (resume_mode) {
-      case JSGeneratorObject::kNext:
-        result = assembler->CallRuntime(Runtime::kCreateIterResultObject,
-                                        context, assembler->UndefinedConstant(),
-                                        assembler->BooleanConstant(true));
-        break;
-      case JSGeneratorObject::kReturn:
-        result =
-            assembler->CallRuntime(Runtime::kCreateIterResultObject, context,
-                                   value, assembler->BooleanConstant(true));
-        break;
-      case JSGeneratorObject::kThrow:
-        result = assembler->CallRuntime(Runtime::kThrow, context, value);
-        break;
-    }
-    assembler->Return(result);
-  }
-
-  assembler->Bind(&if_receiverisrunning);
-  {
-    Node* result =
-        assembler->CallRuntime(Runtime::kThrowGeneratorRunning, context);
-    assembler->Return(result);  // Never reached.
-  }
-}
-
-}  // namespace
-
-// ES6 section 25.3.1.2 Generator.prototype.next ( value )
-void Builtins::Generate_GeneratorPrototypeNext(CodeStubAssembler* assembler) {
-  Generate_GeneratorPrototypeResume(assembler, JSGeneratorObject::kNext,
-                                    "[Generator].prototype.next");
-}
-
-// ES6 section 25.3.1.3 Generator.prototype.return ( value )
-void Builtins::Generate_GeneratorPrototypeReturn(CodeStubAssembler* assembler) {
-  Generate_GeneratorPrototypeResume(assembler, JSGeneratorObject::kReturn,
-                                    "[Generator].prototype.return");
-}
-
-// ES6 section 25.3.1.4 Generator.prototype.throw ( exception )
-void Builtins::Generate_GeneratorPrototypeThrow(CodeStubAssembler* assembler) {
-  Generate_GeneratorPrototypeResume(assembler, JSGeneratorObject::kThrow,
-                                    "[Generator].prototype.throw");
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 26.1 The Reflect Object
-
-// ES6 section 26.1.3 Reflect.defineProperty
-BUILTIN(ReflectDefineProperty) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(4, args.length());
-  Handle<Object> target = args.at<Object>(1);
-  Handle<Object> key = args.at<Object>(2);
-  Handle<Object> attributes = args.at<Object>(3);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.defineProperty")));
-  }
-
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToName(isolate, key));
-
-  PropertyDescriptor desc;
-  if (!PropertyDescriptor::ToPropertyDescriptor(isolate, attributes, &desc)) {
-    return isolate->heap()->exception();
-  }
-
-  Maybe<bool> result =
-      JSReceiver::DefineOwnProperty(isolate, Handle<JSReceiver>::cast(target),
-                                    name, &desc, Object::DONT_THROW);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return *isolate->factory()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 26.1.4 Reflect.deleteProperty
-BUILTIN(ReflectDeleteProperty) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  Handle<Object> target = args.at<Object>(1);
-  Handle<Object> key = args.at<Object>(2);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.deleteProperty")));
-  }
-
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToName(isolate, key));
-
-  Maybe<bool> result = JSReceiver::DeletePropertyOrElement(
-      Handle<JSReceiver>::cast(target), name, SLOPPY);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return *isolate->factory()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 26.1.6 Reflect.get
-BUILTIN(ReflectGet) {
-  HandleScope scope(isolate);
-  Handle<Object> target = args.atOrUndefined(isolate, 1);
-  Handle<Object> key = args.atOrUndefined(isolate, 2);
-  Handle<Object> receiver = args.length() > 3 ? args.at<Object>(3) : target;
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.get")));
-  }
-
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToName(isolate, key));
-
-  RETURN_RESULT_OR_FAILURE(
-      isolate, Object::GetPropertyOrElement(receiver, name,
-                                            Handle<JSReceiver>::cast(target)));
-}
-
-
-// ES6 section 26.1.7 Reflect.getOwnPropertyDescriptor
-BUILTIN(ReflectGetOwnPropertyDescriptor) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  Handle<Object> target = args.at<Object>(1);
-  Handle<Object> key = args.at<Object>(2);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.getOwnPropertyDescriptor")));
-  }
-
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToName(isolate, key));
-
-  PropertyDescriptor desc;
-  Maybe<bool> found = JSReceiver::GetOwnPropertyDescriptor(
-      isolate, Handle<JSReceiver>::cast(target), name, &desc);
-  MAYBE_RETURN(found, isolate->heap()->exception());
-  if (!found.FromJust()) return isolate->heap()->undefined_value();
-  return *desc.ToObject(isolate);
-}
-
-
-// ES6 section 26.1.8 Reflect.getPrototypeOf
-BUILTIN(ReflectGetPrototypeOf) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  Handle<Object> target = args.at<Object>(1);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.getPrototypeOf")));
-  }
-  Handle<JSReceiver> receiver = Handle<JSReceiver>::cast(target);
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           JSReceiver::GetPrototype(isolate, receiver));
-}
-
-
-// ES6 section 26.1.9 Reflect.has
-BUILTIN(ReflectHas) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  Handle<Object> target = args.at<Object>(1);
-  Handle<Object> key = args.at<Object>(2);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.has")));
-  }
-
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToName(isolate, key));
-
-  Maybe<bool> result =
-      JSReceiver::HasProperty(Handle<JSReceiver>::cast(target), name);
-  return result.IsJust() ? *isolate->factory()->ToBoolean(result.FromJust())
-                         : isolate->heap()->exception();
-}
-
-
-// ES6 section 26.1.10 Reflect.isExtensible
-BUILTIN(ReflectIsExtensible) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  Handle<Object> target = args.at<Object>(1);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.isExtensible")));
-  }
-
-  Maybe<bool> result =
-      JSReceiver::IsExtensible(Handle<JSReceiver>::cast(target));
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return *isolate->factory()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 26.1.11 Reflect.ownKeys
-BUILTIN(ReflectOwnKeys) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  Handle<Object> target = args.at<Object>(1);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.ownKeys")));
-  }
-
-  Handle<FixedArray> keys;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, keys,
-      KeyAccumulator::GetKeys(Handle<JSReceiver>::cast(target),
-                              KeyCollectionMode::kOwnOnly, ALL_PROPERTIES,
-                              GetKeysConversion::kConvertToString));
-  return *isolate->factory()->NewJSArrayWithElements(keys);
-}
-
-
-// ES6 section 26.1.12 Reflect.preventExtensions
-BUILTIN(ReflectPreventExtensions) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  Handle<Object> target = args.at<Object>(1);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.preventExtensions")));
-  }
-
-  Maybe<bool> result = JSReceiver::PreventExtensions(
-      Handle<JSReceiver>::cast(target), Object::DONT_THROW);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return *isolate->factory()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 26.1.13 Reflect.set
-BUILTIN(ReflectSet) {
-  HandleScope scope(isolate);
-  Handle<Object> target = args.atOrUndefined(isolate, 1);
-  Handle<Object> key = args.atOrUndefined(isolate, 2);
-  Handle<Object> value = args.atOrUndefined(isolate, 3);
-  Handle<Object> receiver = args.length() > 4 ? args.at<Object>(4) : target;
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.set")));
-  }
-
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToName(isolate, key));
-
-  LookupIterator it = LookupIterator::PropertyOrElement(
-      isolate, receiver, name, Handle<JSReceiver>::cast(target));
-  Maybe<bool> result = Object::SetSuperProperty(
-      &it, value, SLOPPY, Object::MAY_BE_STORE_FROM_KEYED);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return *isolate->factory()->ToBoolean(result.FromJust());
-}
-
-
-// ES6 section 26.1.14 Reflect.setPrototypeOf
-BUILTIN(ReflectSetPrototypeOf) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  Handle<Object> target = args.at<Object>(1);
-  Handle<Object> proto = args.at<Object>(2);
-
-  if (!target->IsJSReceiver()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kCalledOnNonObject,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "Reflect.setPrototypeOf")));
-  }
-
-  if (!proto->IsJSReceiver() && !proto->IsNull(isolate)) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kProtoObjectOrNull, proto));
-  }
-
-  Maybe<bool> result = JSReceiver::SetPrototype(
-      Handle<JSReceiver>::cast(target), proto, true, Object::DONT_THROW);
-  MAYBE_RETURN(result, isolate->heap()->exception());
-  return *isolate->factory()->ToBoolean(result.FromJust());
-}
-
-
-// -----------------------------------------------------------------------------
-// ES6 section 19.3 Boolean Objects
-
-
-// ES6 section 19.3.1.1 Boolean ( value ) for the [[Call]] case.
-BUILTIN(BooleanConstructor) {
-  HandleScope scope(isolate);
-  Handle<Object> value = args.atOrUndefined(isolate, 1);
-  return isolate->heap()->ToBoolean(value->BooleanValue());
-}
-
-
-// ES6 section 19.3.1.1 Boolean ( value ) for the [[Construct]] case.
-BUILTIN(BooleanConstructor_ConstructStub) {
-  HandleScope scope(isolate);
-  Handle<Object> value = args.atOrUndefined(isolate, 1);
-  Handle<JSFunction> target = args.target<JSFunction>();
-  Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
-  DCHECK(*target == target->native_context()->boolean_function());
-  Handle<JSObject> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
-                                     JSObject::New(target, new_target));
-  Handle<JSValue>::cast(result)->set_value(
-      isolate->heap()->ToBoolean(value->BooleanValue()));
-  return *result;
-}
-
-
-// ES6 section 19.3.3.2 Boolean.prototype.toString ( )
-void Builtins::Generate_BooleanPrototypeToString(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  Node* value = assembler->ToThisValue(
-      context, receiver, PrimitiveType::kBoolean, "Boolean.prototype.toString");
-  Node* result = assembler->LoadObjectField(value, Oddball::kToStringOffset);
-  assembler->Return(result);
-}
-
-// ES6 section 19.3.3.3 Boolean.prototype.valueOf ( )
-void Builtins::Generate_BooleanPrototypeValueOf(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  Node* result = assembler->ToThisValue(
-      context, receiver, PrimitiveType::kBoolean, "Boolean.prototype.valueOf");
-  assembler->Return(result);
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 24.2 DataView Objects
-
-
-// ES6 section 24.2.2 The DataView Constructor for the [[Call]] case.
-BUILTIN(DataViewConstructor) {
-  HandleScope scope(isolate);
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate,
-      NewTypeError(MessageTemplate::kConstructorNotFunction,
-                   isolate->factory()->NewStringFromAsciiChecked("DataView")));
-}
-
-
-// ES6 section 24.2.2 The DataView Constructor for the [[Construct]] case.
-BUILTIN(DataViewConstructor_ConstructStub) {
-  HandleScope scope(isolate);
-  Handle<JSFunction> target = args.target<JSFunction>();
-  Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
-  Handle<Object> buffer = args.atOrUndefined(isolate, 1);
-  Handle<Object> byte_offset = args.atOrUndefined(isolate, 2);
-  Handle<Object> byte_length = args.atOrUndefined(isolate, 3);
-
-  // 2. If Type(buffer) is not Object, throw a TypeError exception.
-  // 3. If buffer does not have an [[ArrayBufferData]] internal slot, throw a
-  //    TypeError exception.
-  if (!buffer->IsJSArrayBuffer()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kDataViewNotArrayBuffer));
-  }
-  Handle<JSArrayBuffer> array_buffer = Handle<JSArrayBuffer>::cast(buffer);
-
-  // 4. Let numberOffset be ? ToNumber(byteOffset).
-  Handle<Object> number_offset;
-  if (byte_offset->IsUndefined(isolate)) {
-    // We intentionally violate the specification at this point to allow
-    // for new DataView(buffer) invocations to be equivalent to the full
-    // new DataView(buffer, 0) invocation.
-    number_offset = handle(Smi::FromInt(0), isolate);
-  } else {
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, number_offset,
-                                       Object::ToNumber(byte_offset));
-  }
-
-  // 5. Let offset be ToInteger(numberOffset).
-  Handle<Object> offset;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, offset,
-                                     Object::ToInteger(isolate, number_offset));
-
-  // 6. If numberOffset ≠ offset or offset < 0, throw a RangeError exception.
-  if (number_offset->Number() != offset->Number() || offset->Number() < 0.0) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kInvalidDataViewOffset));
-  }
-
-  // 7. If IsDetachedBuffer(buffer) is true, throw a TypeError exception.
-  // We currently violate the specification at this point.
-
-  // 8. Let bufferByteLength be the value of buffer's [[ArrayBufferByteLength]]
-  // internal slot.
-  double const buffer_byte_length = array_buffer->byte_length()->Number();
-
-  // 9. If offset > bufferByteLength, throw a RangeError exception
-  if (offset->Number() > buffer_byte_length) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kInvalidDataViewOffset));
-  }
-
-  Handle<Object> view_byte_length;
-  if (byte_length->IsUndefined(isolate)) {
-    // 10. If byteLength is undefined, then
-    //       a. Let viewByteLength be bufferByteLength - offset.
-    view_byte_length =
-        isolate->factory()->NewNumber(buffer_byte_length - offset->Number());
-  } else {
-    // 11. Else,
-    //       a. Let viewByteLength be ? ToLength(byteLength).
-    //       b. If offset+viewByteLength > bufferByteLength, throw a RangeError
-    //          exception
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, view_byte_length, Object::ToLength(isolate, byte_length));
-    if (offset->Number() + view_byte_length->Number() > buffer_byte_length) {
-      THROW_NEW_ERROR_RETURN_FAILURE(
-          isolate, NewRangeError(MessageTemplate::kInvalidDataViewLength));
-    }
-  }
-
-  // 12. Let O be ? OrdinaryCreateFromConstructor(NewTarget,
-  //     "%DataViewPrototype%", «[[DataView]], [[ViewedArrayBuffer]],
-  //     [[ByteLength]], [[ByteOffset]]»).
-  // 13. Set O's [[DataView]] internal slot to true.
-  Handle<JSObject> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
-                                     JSObject::New(target, new_target));
-  for (int i = 0; i < ArrayBufferView::kInternalFieldCount; ++i) {
-    Handle<JSDataView>::cast(result)->SetInternalField(i, Smi::FromInt(0));
-  }
-
-  // 14. Set O's [[ViewedArrayBuffer]] internal slot to buffer.
-  Handle<JSDataView>::cast(result)->set_buffer(*array_buffer);
-
-  // 15. Set O's [[ByteLength]] internal slot to viewByteLength.
-  Handle<JSDataView>::cast(result)->set_byte_length(*view_byte_length);
-
-  // 16. Set O's [[ByteOffset]] internal slot to offset.
-  Handle<JSDataView>::cast(result)->set_byte_offset(*offset);
-
-  // 17. Return O.
-  return *result;
-}
-
-// ES6 section 24.2.4.1 get DataView.prototype.buffer
-BUILTIN(DataViewPrototypeGetBuffer) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDataView, data_view, "get DataView.prototype.buffer");
-  return data_view->buffer();
-}
-
-// ES6 section 24.2.4.2 get DataView.prototype.byteLength
-BUILTIN(DataViewPrototypeGetByteLength) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDataView, data_view, "get DataView.prototype.byteLength");
-  // TODO(bmeurer): According to the ES6 spec, we should throw a TypeError
-  // here if the JSArrayBuffer of the {data_view} was neutered.
-  return data_view->byte_length();
-}
-
-// ES6 section 24.2.4.3 get DataView.prototype.byteOffset
-BUILTIN(DataViewPrototypeGetByteOffset) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDataView, data_view, "get DataView.prototype.byteOffset");
-  // TODO(bmeurer): According to the ES6 spec, we should throw a TypeError
-  // here if the JSArrayBuffer of the {data_view} was neutered.
-  return data_view->byte_offset();
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 22.2 TypedArray Objects
-
-// ES6 section 22.2.3.1 get %TypedArray%.prototype.buffer
-BUILTIN(TypedArrayPrototypeBuffer) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSTypedArray, typed_array, "get TypedArray.prototype.buffer");
-  return *typed_array->GetBuffer();
-}
-
-namespace {
-
-void Generate_TypedArrayProtoypeGetter(CodeStubAssembler* assembler,
-                                       const char* method_name,
-                                       int object_offset) {
-  typedef CodeStubAssembler::Label Label;
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  // Check if the {receiver} is actually a JSTypedArray.
-  Label if_receiverisincompatible(assembler, Label::kDeferred);
-  assembler->GotoIf(assembler->WordIsSmi(receiver), &if_receiverisincompatible);
-  Node* receiver_instance_type = assembler->LoadInstanceType(receiver);
-  assembler->GotoUnless(
-      assembler->Word32Equal(receiver_instance_type,
-                             assembler->Int32Constant(JS_TYPED_ARRAY_TYPE)),
-      &if_receiverisincompatible);
-
-  // Check if the {receiver}'s JSArrayBuffer was neutered.
-  Node* receiver_buffer =
-      assembler->LoadObjectField(receiver, JSTypedArray::kBufferOffset);
-  Node* receiver_buffer_bit_field = assembler->LoadObjectField(
-      receiver_buffer, JSArrayBuffer::kBitFieldOffset, MachineType::Uint32());
-  Label if_receiverisneutered(assembler, Label::kDeferred);
-  assembler->GotoUnless(
-      assembler->Word32Equal(
-          assembler->Word32And(
-              receiver_buffer_bit_field,
-              assembler->Int32Constant(JSArrayBuffer::WasNeutered::kMask)),
-          assembler->Int32Constant(0)),
-      &if_receiverisneutered);
-  assembler->Return(assembler->LoadObjectField(receiver, object_offset));
-
-  assembler->Bind(&if_receiverisneutered);
-  {
-    // The {receiver}s buffer was neutered, default to zero.
-    assembler->Return(assembler->SmiConstant(0));
-  }
-
-  assembler->Bind(&if_receiverisincompatible);
-  {
-    // The {receiver} is not a valid JSGeneratorObject.
-    Node* result = assembler->CallRuntime(
-        Runtime::kThrowIncompatibleMethodReceiver, context,
-        assembler->HeapConstant(assembler->factory()->NewStringFromAsciiChecked(
-            method_name, TENURED)),
-        receiver);
-    assembler->Return(result);  // Never reached.
-  }
-}
-
-}  // namespace
-
-// ES6 section 22.2.3.2 get %TypedArray%.prototype.byteLength
-void Builtins::Generate_TypedArrayPrototypeByteLength(
-    CodeStubAssembler* assembler) {
-  Generate_TypedArrayProtoypeGetter(assembler,
-                                    "get TypedArray.prototype.byteLength",
-                                    JSTypedArray::kByteLengthOffset);
-}
-
-// ES6 section 22.2.3.3 get %TypedArray%.prototype.byteOffset
-void Builtins::Generate_TypedArrayPrototypeByteOffset(
-    CodeStubAssembler* assembler) {
-  Generate_TypedArrayProtoypeGetter(assembler,
-                                    "get TypedArray.prototype.byteOffset",
-                                    JSTypedArray::kByteOffsetOffset);
-}
-
-// ES6 section 22.2.3.18 get %TypedArray%.prototype.length
-void Builtins::Generate_TypedArrayPrototypeLength(
-    CodeStubAssembler* assembler) {
-  Generate_TypedArrayProtoypeGetter(assembler,
-                                    "get TypedArray.prototype.length",
-                                    JSTypedArray::kLengthOffset);
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 20.3 Date Objects
-
-
-namespace {
-
-// ES6 section 20.3.1.1 Time Values and Time Range
-const double kMinYear = -1000000.0;
-const double kMaxYear = -kMinYear;
-const double kMinMonth = -10000000.0;
-const double kMaxMonth = -kMinMonth;
-
-
-// 20.3.1.2 Day Number and Time within Day
-const double kMsPerDay = 86400000.0;
-
-
-// ES6 section 20.3.1.11 Hours, Minutes, Second, and Milliseconds
-const double kMsPerSecond = 1000.0;
-const double kMsPerMinute = 60000.0;
-const double kMsPerHour = 3600000.0;
-
-
-// ES6 section 20.3.1.14 MakeDate (day, time)
-double MakeDate(double day, double time) {
-  if (std::isfinite(day) && std::isfinite(time)) {
-    return time + day * kMsPerDay;
-  }
-  return std::numeric_limits<double>::quiet_NaN();
-}
-
-
-// ES6 section 20.3.1.13 MakeDay (year, month, date)
-double MakeDay(double year, double month, double date) {
-  if ((kMinYear <= year && year <= kMaxYear) &&
-      (kMinMonth <= month && month <= kMaxMonth) && std::isfinite(date)) {
-    int y = FastD2I(year);
-    int m = FastD2I(month);
-    y += m / 12;
-    m %= 12;
-    if (m < 0) {
-      m += 12;
-      y -= 1;
-    }
-    DCHECK_LE(0, m);
-    DCHECK_LT(m, 12);
-
-    // kYearDelta is an arbitrary number such that:
-    // a) kYearDelta = -1 (mod 400)
-    // b) year + kYearDelta > 0 for years in the range defined by
-    //    ECMA 262 - 15.9.1.1, i.e. upto 100,000,000 days on either side of
-    //    Jan 1 1970. This is required so that we don't run into integer
-    //    division of negative numbers.
-    // c) there shouldn't be an overflow for 32-bit integers in the following
-    //    operations.
-    static const int kYearDelta = 399999;
-    static const int kBaseDay =
-        365 * (1970 + kYearDelta) + (1970 + kYearDelta) / 4 -
-        (1970 + kYearDelta) / 100 + (1970 + kYearDelta) / 400;
-    int day_from_year = 365 * (y + kYearDelta) + (y + kYearDelta) / 4 -
-                        (y + kYearDelta) / 100 + (y + kYearDelta) / 400 -
-                        kBaseDay;
-    if ((y % 4 != 0) || (y % 100 == 0 && y % 400 != 0)) {
-      static const int kDayFromMonth[] = {0,   31,  59,  90,  120, 151,
-                                          181, 212, 243, 273, 304, 334};
-      day_from_year += kDayFromMonth[m];
-    } else {
-      static const int kDayFromMonth[] = {0,   31,  60,  91,  121, 152,
-                                          182, 213, 244, 274, 305, 335};
-      day_from_year += kDayFromMonth[m];
-    }
-    return static_cast<double>(day_from_year - 1) + date;
-  }
-  return std::numeric_limits<double>::quiet_NaN();
-}
-
-
-// ES6 section 20.3.1.12 MakeTime (hour, min, sec, ms)
-double MakeTime(double hour, double min, double sec, double ms) {
-  if (std::isfinite(hour) && std::isfinite(min) && std::isfinite(sec) &&
-      std::isfinite(ms)) {
-    double const h = DoubleToInteger(hour);
-    double const m = DoubleToInteger(min);
-    double const s = DoubleToInteger(sec);
-    double const milli = DoubleToInteger(ms);
-    return h * kMsPerHour + m * kMsPerMinute + s * kMsPerSecond + milli;
-  }
-  return std::numeric_limits<double>::quiet_NaN();
-}
-
-
-// ES6 section 20.3.1.15 TimeClip (time)
-double TimeClip(double time) {
-  if (-DateCache::kMaxTimeInMs <= time && time <= DateCache::kMaxTimeInMs) {
-    return DoubleToInteger(time) + 0.0;
-  }
-  return std::numeric_limits<double>::quiet_NaN();
-}
-
-
-const char* kShortWeekDays[] = {"Sun", "Mon", "Tue", "Wed",
-                                "Thu", "Fri", "Sat"};
-const char* kShortMonths[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
-                              "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
-
-
-// ES6 section 20.3.1.16 Date Time String Format
-double ParseDateTimeString(Handle<String> str) {
-  Isolate* const isolate = str->GetIsolate();
-  str = String::Flatten(str);
-  // TODO(bmeurer): Change DateParser to not use the FixedArray.
-  Handle<FixedArray> tmp =
-      isolate->factory()->NewFixedArray(DateParser::OUTPUT_SIZE);
-  DisallowHeapAllocation no_gc;
-  String::FlatContent str_content = str->GetFlatContent();
-  bool result;
-  if (str_content.IsOneByte()) {
-    result = DateParser::Parse(isolate, str_content.ToOneByteVector(), *tmp);
-  } else {
-    result = DateParser::Parse(isolate, str_content.ToUC16Vector(), *tmp);
-  }
-  if (!result) return std::numeric_limits<double>::quiet_NaN();
-  double const day = MakeDay(tmp->get(0)->Number(), tmp->get(1)->Number(),
-                             tmp->get(2)->Number());
-  double const time = MakeTime(tmp->get(3)->Number(), tmp->get(4)->Number(),
-                               tmp->get(5)->Number(), tmp->get(6)->Number());
-  double date = MakeDate(day, time);
-  if (tmp->get(7)->IsNull(isolate)) {
-    if (!std::isnan(date)) {
-      date = isolate->date_cache()->ToUTC(static_cast<int64_t>(date));
-    }
-  } else {
-    date -= tmp->get(7)->Number() * 1000.0;
-  }
-  return date;
-}
-
-
-enum ToDateStringMode { kDateOnly, kTimeOnly, kDateAndTime };
-
-
-// ES6 section 20.3.4.41.1 ToDateString(tv)
-void ToDateString(double time_val, Vector<char> str, DateCache* date_cache,
-                  ToDateStringMode mode = kDateAndTime) {
-  if (std::isnan(time_val)) {
-    SNPrintF(str, "Invalid Date");
-    return;
-  }
-  int64_t time_ms = static_cast<int64_t>(time_val);
-  int64_t local_time_ms = date_cache->ToLocal(time_ms);
-  int year, month, day, weekday, hour, min, sec, ms;
-  date_cache->BreakDownTime(local_time_ms, &year, &month, &day, &weekday, &hour,
-                            &min, &sec, &ms);
-  int timezone_offset = -date_cache->TimezoneOffset(time_ms);
-  int timezone_hour = std::abs(timezone_offset) / 60;
-  int timezone_min = std::abs(timezone_offset) % 60;
-  const char* local_timezone = date_cache->LocalTimezone(time_ms);
-  switch (mode) {
-    case kDateOnly:
-      SNPrintF(str, "%s %s %02d %4d", kShortWeekDays[weekday],
-               kShortMonths[month], day, year);
-      return;
-    case kTimeOnly:
-      SNPrintF(str, "%02d:%02d:%02d GMT%c%02d%02d (%s)", hour, min, sec,
-               (timezone_offset < 0) ? '-' : '+', timezone_hour, timezone_min,
-               local_timezone);
-      return;
-    case kDateAndTime:
-      SNPrintF(str, "%s %s %02d %4d %02d:%02d:%02d GMT%c%02d%02d (%s)",
-               kShortWeekDays[weekday], kShortMonths[month], day, year, hour,
-               min, sec, (timezone_offset < 0) ? '-' : '+', timezone_hour,
-               timezone_min, local_timezone);
-      return;
-  }
-  UNREACHABLE();
-}
-
-
-Object* SetLocalDateValue(Handle<JSDate> date, double time_val) {
-  if (time_val >= -DateCache::kMaxTimeBeforeUTCInMs &&
-      time_val <= DateCache::kMaxTimeBeforeUTCInMs) {
-    Isolate* const isolate = date->GetIsolate();
-    time_val = isolate->date_cache()->ToUTC(static_cast<int64_t>(time_val));
-  } else {
-    time_val = std::numeric_limits<double>::quiet_NaN();
-  }
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-}  // namespace
-
-
-// ES6 section 20.3.2 The Date Constructor for the [[Call]] case.
-BUILTIN(DateConstructor) {
-  HandleScope scope(isolate);
-  double const time_val = JSDate::CurrentTimeValue(isolate);
-  char buffer[128];
-  ToDateString(time_val, ArrayVector(buffer), isolate->date_cache());
-  RETURN_RESULT_OR_FAILURE(
-      isolate, isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
-}
-
-
-// ES6 section 20.3.2 The Date Constructor for the [[Construct]] case.
-BUILTIN(DateConstructor_ConstructStub) {
-  HandleScope scope(isolate);
-  int const argc = args.length() - 1;
-  Handle<JSFunction> target = args.target<JSFunction>();
-  Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
-  double time_val;
-  if (argc == 0) {
-    time_val = JSDate::CurrentTimeValue(isolate);
-  } else if (argc == 1) {
-    Handle<Object> value = args.at<Object>(1);
-    if (value->IsJSDate()) {
-      time_val = Handle<JSDate>::cast(value)->value()->Number();
-    } else {
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, value,
-                                         Object::ToPrimitive(value));
-      if (value->IsString()) {
-        time_val = ParseDateTimeString(Handle<String>::cast(value));
-      } else {
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, value,
-                                           Object::ToNumber(value));
-        time_val = value->Number();
-      }
-    }
-  } else {
-    Handle<Object> year_object;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, year_object,
-                                       Object::ToNumber(args.at<Object>(1)));
-    Handle<Object> month_object;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, month_object,
-                                       Object::ToNumber(args.at<Object>(2)));
-    double year = year_object->Number();
-    double month = month_object->Number();
-    double date = 1.0, hours = 0.0, minutes = 0.0, seconds = 0.0, ms = 0.0;
-    if (argc >= 3) {
-      Handle<Object> date_object;
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, date_object,
-                                         Object::ToNumber(args.at<Object>(3)));
-      date = date_object->Number();
-      if (argc >= 4) {
-        Handle<Object> hours_object;
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-            isolate, hours_object, Object::ToNumber(args.at<Object>(4)));
-        hours = hours_object->Number();
-        if (argc >= 5) {
-          Handle<Object> minutes_object;
-          ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-              isolate, minutes_object, Object::ToNumber(args.at<Object>(5)));
-          minutes = minutes_object->Number();
-          if (argc >= 6) {
-            Handle<Object> seconds_object;
-            ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-                isolate, seconds_object, Object::ToNumber(args.at<Object>(6)));
-            seconds = seconds_object->Number();
-            if (argc >= 7) {
-              Handle<Object> ms_object;
-              ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-                  isolate, ms_object, Object::ToNumber(args.at<Object>(7)));
-              ms = ms_object->Number();
-            }
-          }
-        }
-      }
-    }
-    if (!std::isnan(year)) {
-      double const y = DoubleToInteger(year);
-      if (0.0 <= y && y <= 99) year = 1900 + y;
-    }
-    double const day = MakeDay(year, month, date);
-    double const time = MakeTime(hours, minutes, seconds, ms);
-    time_val = MakeDate(day, time);
-    if (time_val >= -DateCache::kMaxTimeBeforeUTCInMs &&
-        time_val <= DateCache::kMaxTimeBeforeUTCInMs) {
-      time_val = isolate->date_cache()->ToUTC(static_cast<int64_t>(time_val));
-    } else {
-      time_val = std::numeric_limits<double>::quiet_NaN();
-    }
-  }
-  RETURN_RESULT_OR_FAILURE(isolate, JSDate::New(target, new_target, time_val));
-}
-
-
-// ES6 section 20.3.3.1 Date.now ( )
-BUILTIN(DateNow) {
-  HandleScope scope(isolate);
-  return *isolate->factory()->NewNumber(JSDate::CurrentTimeValue(isolate));
-}
-
-
-// ES6 section 20.3.3.2 Date.parse ( string )
-BUILTIN(DateParse) {
-  HandleScope scope(isolate);
-  Handle<String> string;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, string,
-      Object::ToString(isolate, args.atOrUndefined(isolate, 1)));
-  return *isolate->factory()->NewNumber(ParseDateTimeString(string));
-}
-
-
-// ES6 section 20.3.3.4 Date.UTC (year,month,date,hours,minutes,seconds,ms)
-BUILTIN(DateUTC) {
-  HandleScope scope(isolate);
-  int const argc = args.length() - 1;
-  double year = std::numeric_limits<double>::quiet_NaN();
-  double month = std::numeric_limits<double>::quiet_NaN();
-  double date = 1.0, hours = 0.0, minutes = 0.0, seconds = 0.0, ms = 0.0;
-  if (argc >= 1) {
-    Handle<Object> year_object;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, year_object,
-                                       Object::ToNumber(args.at<Object>(1)));
-    year = year_object->Number();
-    if (argc >= 2) {
-      Handle<Object> month_object;
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, month_object,
-                                         Object::ToNumber(args.at<Object>(2)));
-      month = month_object->Number();
-      if (argc >= 3) {
-        Handle<Object> date_object;
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-            isolate, date_object, Object::ToNumber(args.at<Object>(3)));
-        date = date_object->Number();
-        if (argc >= 4) {
-          Handle<Object> hours_object;
-          ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-              isolate, hours_object, Object::ToNumber(args.at<Object>(4)));
-          hours = hours_object->Number();
-          if (argc >= 5) {
-            Handle<Object> minutes_object;
-            ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-                isolate, minutes_object, Object::ToNumber(args.at<Object>(5)));
-            minutes = minutes_object->Number();
-            if (argc >= 6) {
-              Handle<Object> seconds_object;
-              ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-                  isolate, seconds_object,
-                  Object::ToNumber(args.at<Object>(6)));
-              seconds = seconds_object->Number();
-              if (argc >= 7) {
-                Handle<Object> ms_object;
-                ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-                    isolate, ms_object, Object::ToNumber(args.at<Object>(7)));
-                ms = ms_object->Number();
-              }
-            }
-          }
-        }
-      }
-    }
-  }
-  if (!std::isnan(year)) {
-    double const y = DoubleToInteger(year);
-    if (0.0 <= y && y <= 99) year = 1900 + y;
-  }
-  double const day = MakeDay(year, month, date);
-  double const time = MakeTime(hours, minutes, seconds, ms);
-  return *isolate->factory()->NewNumber(TimeClip(MakeDate(day, time)));
-}
-
-
-// ES6 section 20.3.4.20 Date.prototype.setDate ( date )
-BUILTIN(DatePrototypeSetDate) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setDate");
-  Handle<Object> value = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, value, Object::ToNumber(value));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int const days = isolate->date_cache()->DaysFromTime(local_time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, days);
-    int year, month, day;
-    isolate->date_cache()->YearMonthDayFromDays(days, &year, &month, &day);
-    time_val = MakeDate(MakeDay(year, month, value->Number()), time_within_day);
-  }
-  return SetLocalDateValue(date, time_val);
-}
-
-
-// ES6 section 20.3.4.21 Date.prototype.setFullYear (year, month, date)
-BUILTIN(DatePrototypeSetFullYear) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setFullYear");
-  int const argc = args.length() - 1;
-  Handle<Object> year = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, year, Object::ToNumber(year));
-  double y = year->Number(), m = 0.0, dt = 1.0;
-  int time_within_day = 0;
-  if (!std::isnan(date->value()->Number())) {
-    int64_t const time_ms = static_cast<int64_t>(date->value()->Number());
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int const days = isolate->date_cache()->DaysFromTime(local_time_ms);
-    time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, days);
-    int year, month, day;
-    isolate->date_cache()->YearMonthDayFromDays(days, &year, &month, &day);
-    m = month;
-    dt = day;
-  }
-  if (argc >= 2) {
-    Handle<Object> month = args.at<Object>(2);
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, month, Object::ToNumber(month));
-    m = month->Number();
-    if (argc >= 3) {
-      Handle<Object> date = args.at<Object>(3);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, date, Object::ToNumber(date));
-      dt = date->Number();
-    }
-  }
-  double time_val = MakeDate(MakeDay(y, m, dt), time_within_day);
-  return SetLocalDateValue(date, time_val);
-}
-
-
-// ES6 section 20.3.4.22 Date.prototype.setHours(hour, min, sec, ms)
-BUILTIN(DatePrototypeSetHours) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setHours");
-  int const argc = args.length() - 1;
-  Handle<Object> hour = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, hour, Object::ToNumber(hour));
-  double h = hour->Number();
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int day = isolate->date_cache()->DaysFromTime(local_time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, day);
-    double m = (time_within_day / (60 * 1000)) % 60;
-    double s = (time_within_day / 1000) % 60;
-    double milli = time_within_day % 1000;
-    if (argc >= 2) {
-      Handle<Object> min = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, min, Object::ToNumber(min));
-      m = min->Number();
-      if (argc >= 3) {
-        Handle<Object> sec = args.at<Object>(3);
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, sec, Object::ToNumber(sec));
-        s = sec->Number();
-        if (argc >= 4) {
-          Handle<Object> ms = args.at<Object>(4);
-          ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-          milli = ms->Number();
-        }
-      }
-    }
-    time_val = MakeDate(day, MakeTime(h, m, s, milli));
-  }
-  return SetLocalDateValue(date, time_val);
-}
-
-
-// ES6 section 20.3.4.23 Date.prototype.setMilliseconds(ms)
-BUILTIN(DatePrototypeSetMilliseconds) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setMilliseconds");
-  Handle<Object> ms = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int day = isolate->date_cache()->DaysFromTime(local_time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, day);
-    int h = time_within_day / (60 * 60 * 1000);
-    int m = (time_within_day / (60 * 1000)) % 60;
-    int s = (time_within_day / 1000) % 60;
-    time_val = MakeDate(day, MakeTime(h, m, s, ms->Number()));
-  }
-  return SetLocalDateValue(date, time_val);
-}
-
-
-// ES6 section 20.3.4.24 Date.prototype.setMinutes ( min, sec, ms )
-BUILTIN(DatePrototypeSetMinutes) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setMinutes");
-  int const argc = args.length() - 1;
-  Handle<Object> min = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, min, Object::ToNumber(min));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int day = isolate->date_cache()->DaysFromTime(local_time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, day);
-    int h = time_within_day / (60 * 60 * 1000);
-    double m = min->Number();
-    double s = (time_within_day / 1000) % 60;
-    double milli = time_within_day % 1000;
-    if (argc >= 2) {
-      Handle<Object> sec = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, sec, Object::ToNumber(sec));
-      s = sec->Number();
-      if (argc >= 3) {
-        Handle<Object> ms = args.at<Object>(3);
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-        milli = ms->Number();
-      }
-    }
-    time_val = MakeDate(day, MakeTime(h, m, s, milli));
-  }
-  return SetLocalDateValue(date, time_val);
-}
-
-
-// ES6 section 20.3.4.25 Date.prototype.setMonth ( month, date )
-BUILTIN(DatePrototypeSetMonth) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setMonth");
-  int const argc = args.length() - 1;
-  Handle<Object> month = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, month, Object::ToNumber(month));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int days = isolate->date_cache()->DaysFromTime(local_time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, days);
-    int year, unused, day;
-    isolate->date_cache()->YearMonthDayFromDays(days, &year, &unused, &day);
-    double m = month->Number();
-    double dt = day;
-    if (argc >= 2) {
-      Handle<Object> date = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, date, Object::ToNumber(date));
-      dt = date->Number();
-    }
-    time_val = MakeDate(MakeDay(year, m, dt), time_within_day);
-  }
-  return SetLocalDateValue(date, time_val);
-}
-
-
-// ES6 section 20.3.4.26 Date.prototype.setSeconds ( sec, ms )
-BUILTIN(DatePrototypeSetSeconds) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setSeconds");
-  int const argc = args.length() - 1;
-  Handle<Object> sec = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, sec, Object::ToNumber(sec));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int day = isolate->date_cache()->DaysFromTime(local_time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, day);
-    int h = time_within_day / (60 * 60 * 1000);
-    double m = (time_within_day / (60 * 1000)) % 60;
-    double s = sec->Number();
-    double milli = time_within_day % 1000;
-    if (argc >= 2) {
-      Handle<Object> ms = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-      milli = ms->Number();
-    }
-    time_val = MakeDate(day, MakeTime(h, m, s, milli));
-  }
-  return SetLocalDateValue(date, time_val);
-}
-
-
-// ES6 section 20.3.4.27 Date.prototype.setTime ( time )
-BUILTIN(DatePrototypeSetTime) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setTime");
-  Handle<Object> value = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, value, Object::ToNumber(value));
-  return *JSDate::SetValue(date, TimeClip(value->Number()));
-}
-
-
-// ES6 section 20.3.4.28 Date.prototype.setUTCDate ( date )
-BUILTIN(DatePrototypeSetUTCDate) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setUTCDate");
-  Handle<Object> value = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, value, Object::ToNumber(value));
-  if (std::isnan(date->value()->Number())) return date->value();
-  int64_t const time_ms = static_cast<int64_t>(date->value()->Number());
-  int const days = isolate->date_cache()->DaysFromTime(time_ms);
-  int const time_within_day = isolate->date_cache()->TimeInDay(time_ms, days);
-  int year, month, day;
-  isolate->date_cache()->YearMonthDayFromDays(days, &year, &month, &day);
-  double const time_val =
-      MakeDate(MakeDay(year, month, value->Number()), time_within_day);
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-
-// ES6 section 20.3.4.29 Date.prototype.setUTCFullYear (year, month, date)
-BUILTIN(DatePrototypeSetUTCFullYear) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setUTCFullYear");
-  int const argc = args.length() - 1;
-  Handle<Object> year = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, year, Object::ToNumber(year));
-  double y = year->Number(), m = 0.0, dt = 1.0;
-  int time_within_day = 0;
-  if (!std::isnan(date->value()->Number())) {
-    int64_t const time_ms = static_cast<int64_t>(date->value()->Number());
-    int const days = isolate->date_cache()->DaysFromTime(time_ms);
-    time_within_day = isolate->date_cache()->TimeInDay(time_ms, days);
-    int year, month, day;
-    isolate->date_cache()->YearMonthDayFromDays(days, &year, &month, &day);
-    m = month;
-    dt = day;
-  }
-  if (argc >= 2) {
-    Handle<Object> month = args.at<Object>(2);
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, month, Object::ToNumber(month));
-    m = month->Number();
-    if (argc >= 3) {
-      Handle<Object> date = args.at<Object>(3);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, date, Object::ToNumber(date));
-      dt = date->Number();
-    }
-  }
-  double const time_val = MakeDate(MakeDay(y, m, dt), time_within_day);
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-
-// ES6 section 20.3.4.30 Date.prototype.setUTCHours(hour, min, sec, ms)
-BUILTIN(DatePrototypeSetUTCHours) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setUTCHours");
-  int const argc = args.length() - 1;
-  Handle<Object> hour = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, hour, Object::ToNumber(hour));
-  double h = hour->Number();
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int day = isolate->date_cache()->DaysFromTime(time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(time_ms, day);
-    double m = (time_within_day / (60 * 1000)) % 60;
-    double s = (time_within_day / 1000) % 60;
-    double milli = time_within_day % 1000;
-    if (argc >= 2) {
-      Handle<Object> min = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, min, Object::ToNumber(min));
-      m = min->Number();
-      if (argc >= 3) {
-        Handle<Object> sec = args.at<Object>(3);
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, sec, Object::ToNumber(sec));
-        s = sec->Number();
-        if (argc >= 4) {
-          Handle<Object> ms = args.at<Object>(4);
-          ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-          milli = ms->Number();
-        }
-      }
-    }
-    time_val = MakeDate(day, MakeTime(h, m, s, milli));
-  }
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-
-// ES6 section 20.3.4.31 Date.prototype.setUTCMilliseconds(ms)
-BUILTIN(DatePrototypeSetUTCMilliseconds) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setUTCMilliseconds");
-  Handle<Object> ms = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int day = isolate->date_cache()->DaysFromTime(time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(time_ms, day);
-    int h = time_within_day / (60 * 60 * 1000);
-    int m = (time_within_day / (60 * 1000)) % 60;
-    int s = (time_within_day / 1000) % 60;
-    time_val = MakeDate(day, MakeTime(h, m, s, ms->Number()));
-  }
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-
-// ES6 section 20.3.4.32 Date.prototype.setUTCMinutes ( min, sec, ms )
-BUILTIN(DatePrototypeSetUTCMinutes) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setUTCMinutes");
-  int const argc = args.length() - 1;
-  Handle<Object> min = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, min, Object::ToNumber(min));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int day = isolate->date_cache()->DaysFromTime(time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(time_ms, day);
-    int h = time_within_day / (60 * 60 * 1000);
-    double m = min->Number();
-    double s = (time_within_day / 1000) % 60;
-    double milli = time_within_day % 1000;
-    if (argc >= 2) {
-      Handle<Object> sec = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, sec, Object::ToNumber(sec));
-      s = sec->Number();
-      if (argc >= 3) {
-        Handle<Object> ms = args.at<Object>(3);
-        ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-        milli = ms->Number();
-      }
-    }
-    time_val = MakeDate(day, MakeTime(h, m, s, milli));
-  }
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-
-// ES6 section 20.3.4.31 Date.prototype.setUTCMonth ( month, date )
-BUILTIN(DatePrototypeSetUTCMonth) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setUTCMonth");
-  int const argc = args.length() - 1;
-  Handle<Object> month = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, month, Object::ToNumber(month));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int days = isolate->date_cache()->DaysFromTime(time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(time_ms, days);
-    int year, unused, day;
-    isolate->date_cache()->YearMonthDayFromDays(days, &year, &unused, &day);
-    double m = month->Number();
-    double dt = day;
-    if (argc >= 2) {
-      Handle<Object> date = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, date, Object::ToNumber(date));
-      dt = date->Number();
-    }
-    time_val = MakeDate(MakeDay(year, m, dt), time_within_day);
-  }
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-
-// ES6 section 20.3.4.34 Date.prototype.setUTCSeconds ( sec, ms )
-BUILTIN(DatePrototypeSetUTCSeconds) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setUTCSeconds");
-  int const argc = args.length() - 1;
-  Handle<Object> sec = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, sec, Object::ToNumber(sec));
-  double time_val = date->value()->Number();
-  if (!std::isnan(time_val)) {
-    int64_t const time_ms = static_cast<int64_t>(time_val);
-    int day = isolate->date_cache()->DaysFromTime(time_ms);
-    int time_within_day = isolate->date_cache()->TimeInDay(time_ms, day);
-    int h = time_within_day / (60 * 60 * 1000);
-    double m = (time_within_day / (60 * 1000)) % 60;
-    double s = sec->Number();
-    double milli = time_within_day % 1000;
-    if (argc >= 2) {
-      Handle<Object> ms = args.at<Object>(2);
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, ms, Object::ToNumber(ms));
-      milli = ms->Number();
-    }
-    time_val = MakeDate(day, MakeTime(h, m, s, milli));
-  }
-  return *JSDate::SetValue(date, TimeClip(time_val));
-}
-
-
-// ES6 section 20.3.4.35 Date.prototype.toDateString ( )
-BUILTIN(DatePrototypeToDateString) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.toDateString");
-  char buffer[128];
-  ToDateString(date->value()->Number(), ArrayVector(buffer),
-               isolate->date_cache(), kDateOnly);
-  RETURN_RESULT_OR_FAILURE(
-      isolate, isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
-}
-
-
-// ES6 section 20.3.4.36 Date.prototype.toISOString ( )
-BUILTIN(DatePrototypeToISOString) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.toISOString");
-  double const time_val = date->value()->Number();
-  if (std::isnan(time_val)) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kInvalidTimeValue));
-  }
-  int64_t const time_ms = static_cast<int64_t>(time_val);
-  int year, month, day, weekday, hour, min, sec, ms;
-  isolate->date_cache()->BreakDownTime(time_ms, &year, &month, &day, &weekday,
-                                       &hour, &min, &sec, &ms);
-  char buffer[128];
-  if (year >= 0 && year <= 9999) {
-    SNPrintF(ArrayVector(buffer), "%04d-%02d-%02dT%02d:%02d:%02d.%03dZ", year,
-             month + 1, day, hour, min, sec, ms);
-  } else if (year < 0) {
-    SNPrintF(ArrayVector(buffer), "-%06d-%02d-%02dT%02d:%02d:%02d.%03dZ", -year,
-             month + 1, day, hour, min, sec, ms);
-  } else {
-    SNPrintF(ArrayVector(buffer), "+%06d-%02d-%02dT%02d:%02d:%02d.%03dZ", year,
-             month + 1, day, hour, min, sec, ms);
-  }
-  return *isolate->factory()->NewStringFromAsciiChecked(buffer);
-}
-
-
-// ES6 section 20.3.4.41 Date.prototype.toString ( )
-BUILTIN(DatePrototypeToString) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.toString");
-  char buffer[128];
-  ToDateString(date->value()->Number(), ArrayVector(buffer),
-               isolate->date_cache());
-  RETURN_RESULT_OR_FAILURE(
-      isolate, isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
-}
-
-
-// ES6 section 20.3.4.42 Date.prototype.toTimeString ( )
-BUILTIN(DatePrototypeToTimeString) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.toTimeString");
-  char buffer[128];
-  ToDateString(date->value()->Number(), ArrayVector(buffer),
-               isolate->date_cache(), kTimeOnly);
-  RETURN_RESULT_OR_FAILURE(
-      isolate, isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
-}
-
-
-// ES6 section 20.3.4.43 Date.prototype.toUTCString ( )
-BUILTIN(DatePrototypeToUTCString) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.toUTCString");
-  double const time_val = date->value()->Number();
-  if (std::isnan(time_val)) {
-    return *isolate->factory()->NewStringFromAsciiChecked("Invalid Date");
-  }
-  char buffer[128];
-  int64_t time_ms = static_cast<int64_t>(time_val);
-  int year, month, day, weekday, hour, min, sec, ms;
-  isolate->date_cache()->BreakDownTime(time_ms, &year, &month, &day, &weekday,
-                                       &hour, &min, &sec, &ms);
-  SNPrintF(ArrayVector(buffer), "%s, %02d %s %4d %02d:%02d:%02d GMT",
-           kShortWeekDays[weekday], day, kShortMonths[month], year, hour, min,
-           sec);
-  return *isolate->factory()->NewStringFromAsciiChecked(buffer);
-}
-
-
-// ES6 section 20.3.4.44 Date.prototype.valueOf ( )
-BUILTIN(DatePrototypeValueOf) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.valueOf");
-  return date->value();
-}
-
-
-// ES6 section 20.3.4.45 Date.prototype [ @@toPrimitive ] ( hint )
-BUILTIN(DatePrototypeToPrimitive) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  CHECK_RECEIVER(JSReceiver, receiver, "Date.prototype [ @@toPrimitive ]");
-  Handle<Object> hint = args.at<Object>(1);
-  RETURN_RESULT_OR_FAILURE(isolate, JSDate::ToPrimitive(receiver, hint));
-}
-
-
-// ES6 section B.2.4.1 Date.prototype.getYear ( )
-BUILTIN(DatePrototypeGetYear) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.getYear");
-  double time_val = date->value()->Number();
-  if (std::isnan(time_val)) return date->value();
-  int64_t time_ms = static_cast<int64_t>(time_val);
-  int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-  int days = isolate->date_cache()->DaysFromTime(local_time_ms);
-  int year, month, day;
-  isolate->date_cache()->YearMonthDayFromDays(days, &year, &month, &day);
-  return Smi::FromInt(year - 1900);
-}
-
-
-// ES6 section B.2.4.2 Date.prototype.setYear ( year )
-BUILTIN(DatePrototypeSetYear) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSDate, date, "Date.prototype.setYear");
-  Handle<Object> year = args.atOrUndefined(isolate, 1);
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, year, Object::ToNumber(year));
-  double m = 0.0, dt = 1.0, y = year->Number();
-  if (0.0 <= y && y <= 99.0) {
-    y = 1900.0 + DoubleToInteger(y);
-  }
-  int time_within_day = 0;
-  if (!std::isnan(date->value()->Number())) {
-    int64_t const time_ms = static_cast<int64_t>(date->value()->Number());
-    int64_t local_time_ms = isolate->date_cache()->ToLocal(time_ms);
-    int const days = isolate->date_cache()->DaysFromTime(local_time_ms);
-    time_within_day = isolate->date_cache()->TimeInDay(local_time_ms, days);
-    int year, month, day;
-    isolate->date_cache()->YearMonthDayFromDays(days, &year, &month, &day);
-    m = month;
-    dt = day;
-  }
-  double time_val = MakeDate(MakeDay(y, m, dt), time_within_day);
-  return SetLocalDateValue(date, time_val);
-}
-
-// ES6 section 20.3.4.37 Date.prototype.toJSON ( key )
-BUILTIN(DatePrototypeToJson) {
-  HandleScope scope(isolate);
-  Handle<Object> receiver = args.atOrUndefined(isolate, 0);
-  Handle<JSReceiver> receiver_obj;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, receiver_obj,
-                                     Object::ToObject(isolate, receiver));
-  Handle<Object> primitive;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, primitive,
-      Object::ToPrimitive(receiver_obj, ToPrimitiveHint::kNumber));
-  if (primitive->IsNumber() && !std::isfinite(primitive->Number())) {
-    return isolate->heap()->null_value();
-  } else {
-    Handle<String> name =
-        isolate->factory()->NewStringFromAsciiChecked("toISOString");
-    Handle<Object> function;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, function,
-                                       Object::GetProperty(receiver_obj, name));
-    if (!function->IsCallable()) {
-      THROW_NEW_ERROR_RETURN_FAILURE(
-          isolate, NewTypeError(MessageTemplate::kCalledNonCallable, name));
-    }
-    RETURN_RESULT_OR_FAILURE(
-        isolate, Execution::Call(isolate, function, receiver_obj, 0, NULL));
-  }
-}
-
-// static
-void Builtins::Generate_DatePrototypeGetDate(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kDay);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetDay(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kWeekday);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetFullYear(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kYear);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetHours(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kHour);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetMilliseconds(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kMillisecond);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetMinutes(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kMinute);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetMonth(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kMonth);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetSeconds(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kSecond);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetTime(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kDateValue);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetTimezoneOffset(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kTimezoneOffset);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCDate(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kDayUTC);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCDay(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kWeekdayUTC);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCFullYear(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kYearUTC);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCHours(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kHourUTC);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCMilliseconds(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kMillisecondUTC);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCMinutes(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kMinuteUTC);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCMonth(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kMonthUTC);
-}
-
-
-// static
-void Builtins::Generate_DatePrototypeGetUTCSeconds(MacroAssembler* masm) {
-  Generate_DatePrototype_GetField(masm, JSDate::kSecondUTC);
-}
-
-
-namespace {
-
-// ES6 section 19.2.1.1.1 CreateDynamicFunction
-MaybeHandle<JSFunction> CreateDynamicFunction(Isolate* isolate,
-                                              BuiltinArguments args,
-                                              const char* token) {
-  // Compute number of arguments, ignoring the receiver.
-  DCHECK_LE(1, args.length());
-  int const argc = args.length() - 1;
-
-  // Build the source string.
-  Handle<String> source;
-  {
-    IncrementalStringBuilder builder(isolate);
-    builder.AppendCharacter('(');
-    builder.AppendCString(token);
-    builder.AppendCharacter('(');
-    bool parenthesis_in_arg_string = false;
-    if (argc > 1) {
-      for (int i = 1; i < argc; ++i) {
-        if (i > 1) builder.AppendCharacter(',');
-        Handle<String> param;
-        ASSIGN_RETURN_ON_EXCEPTION(
-            isolate, param, Object::ToString(isolate, args.at<Object>(i)),
-            JSFunction);
-        param = String::Flatten(param);
-        builder.AppendString(param);
-        // If the formal parameters string include ) - an illegal
-        // character - it may make the combined function expression
-        // compile. We avoid this problem by checking for this early on.
-        DisallowHeapAllocation no_gc;  // Ensure vectors stay valid.
-        String::FlatContent param_content = param->GetFlatContent();
-        for (int i = 0, length = param->length(); i < length; ++i) {
-          if (param_content.Get(i) == ')') {
-            parenthesis_in_arg_string = true;
-            break;
-          }
-        }
-      }
-      // If the formal parameters include an unbalanced block comment, the
-      // function must be rejected. Since JavaScript does not allow nested
-      // comments we can include a trailing block comment to catch this.
-      builder.AppendCString("\n/**/");
-    }
-    builder.AppendCString(") {\n");
-    if (argc > 0) {
-      Handle<String> body;
-      ASSIGN_RETURN_ON_EXCEPTION(
-          isolate, body, Object::ToString(isolate, args.at<Object>(argc)),
-          JSFunction);
-      builder.AppendString(body);
-    }
-    builder.AppendCString("\n})");
-    ASSIGN_RETURN_ON_EXCEPTION(isolate, source, builder.Finish(), JSFunction);
-
-    // The SyntaxError must be thrown after all the (observable) ToString
-    // conversions are done.
-    if (parenthesis_in_arg_string) {
-      THROW_NEW_ERROR(isolate,
-                      NewSyntaxError(MessageTemplate::kParenthesisInArgString),
-                      JSFunction);
-    }
-  }
-
-  // Compile the string in the constructor and not a helper so that errors to
-  // come from here.
-  Handle<JSFunction> target = args.target<JSFunction>();
-  Handle<JSObject> target_global_proxy(target->global_proxy(), isolate);
-  Handle<JSFunction> function;
-  {
-    ASSIGN_RETURN_ON_EXCEPTION(
-        isolate, function,
-        CompileString(handle(target->native_context(), isolate), source,
-                      ONLY_SINGLE_FUNCTION_LITERAL),
-        JSFunction);
-    Handle<Object> result;
-    ASSIGN_RETURN_ON_EXCEPTION(
-        isolate, result,
-        Execution::Call(isolate, function, target_global_proxy, 0, nullptr),
-        JSFunction);
-    function = Handle<JSFunction>::cast(result);
-    function->shared()->set_name_should_print_as_anonymous(true);
-  }
-
-  // If new.target is equal to target then the function created
-  // is already correctly setup and nothing else should be done
-  // here. But if new.target is not equal to target then we are
-  // have a Function builtin subclassing case and therefore the
-  // function has wrong initial map. To fix that we create a new
-  // function object with correct initial map.
-  Handle<Object> unchecked_new_target = args.new_target();
-  if (!unchecked_new_target->IsUndefined(isolate) &&
-      !unchecked_new_target.is_identical_to(target)) {
-    Handle<JSReceiver> new_target =
-        Handle<JSReceiver>::cast(unchecked_new_target);
-    Handle<Map> initial_map;
-    ASSIGN_RETURN_ON_EXCEPTION(
-        isolate, initial_map,
-        JSFunction::GetDerivedMap(isolate, target, new_target), JSFunction);
-
-    Handle<SharedFunctionInfo> shared_info(function->shared(), isolate);
-    Handle<Map> map = Map::AsLanguageMode(
-        initial_map, shared_info->language_mode(), shared_info->kind());
-
-    Handle<Context> context(function->context(), isolate);
-    function = isolate->factory()->NewFunctionFromSharedFunctionInfo(
-        map, shared_info, context, NOT_TENURED);
-  }
-  return function;
-}
-
-}  // namespace
-
-
-// ES6 section 19.2.1.1 Function ( p1, p2, ... , pn, body )
-BUILTIN(FunctionConstructor) {
-  HandleScope scope(isolate);
-  Handle<JSFunction> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, result, CreateDynamicFunction(isolate, args, "function"));
-  return *result;
-}
-
-namespace {
-
-Object* DoFunctionBind(Isolate* isolate, BuiltinArguments args) {
-  HandleScope scope(isolate);
-  DCHECK_LE(1, args.length());
-  if (!args.receiver()->IsCallable()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kFunctionBind));
-  }
-
-  // Allocate the bound function with the given {this_arg} and {args}.
-  Handle<JSReceiver> target = args.at<JSReceiver>(0);
-  Handle<Object> this_arg = isolate->factory()->undefined_value();
-  ScopedVector<Handle<Object>> argv(std::max(0, args.length() - 2));
-  if (args.length() > 1) {
-    this_arg = args.at<Object>(1);
-    for (int i = 2; i < args.length(); ++i) {
-      argv[i - 2] = args.at<Object>(i);
-    }
-  }
-  Handle<JSBoundFunction> function;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, function,
-      isolate->factory()->NewJSBoundFunction(target, this_arg, argv));
-
-  LookupIterator length_lookup(target, isolate->factory()->length_string(),
-                               target, LookupIterator::OWN);
-  // Setup the "length" property based on the "length" of the {target}.
-  // If the targets length is the default JSFunction accessor, we can keep the
-  // accessor that's installed by default on the JSBoundFunction. It lazily
-  // computes the value from the underlying internal length.
-  if (!target->IsJSFunction() ||
-      length_lookup.state() != LookupIterator::ACCESSOR ||
-      !length_lookup.GetAccessors()->IsAccessorInfo()) {
-    Handle<Object> length(Smi::FromInt(0), isolate);
-    Maybe<PropertyAttributes> attributes =
-        JSReceiver::GetPropertyAttributes(&length_lookup);
-    if (!attributes.IsJust()) return isolate->heap()->exception();
-    if (attributes.FromJust() != ABSENT) {
-      Handle<Object> target_length;
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, target_length,
-                                         Object::GetProperty(&length_lookup));
-      if (target_length->IsNumber()) {
-        length = isolate->factory()->NewNumber(std::max(
-            0.0, DoubleToInteger(target_length->Number()) - argv.length()));
-      }
-    }
-    LookupIterator it(function, isolate->factory()->length_string(), function);
-    DCHECK_EQ(LookupIterator::ACCESSOR, it.state());
-    RETURN_FAILURE_ON_EXCEPTION(isolate,
-                                JSObject::DefineOwnPropertyIgnoreAttributes(
-                                    &it, length, it.property_attributes()));
-  }
-
-  // Setup the "name" property based on the "name" of the {target}.
-  // If the targets name is the default JSFunction accessor, we can keep the
-  // accessor that's installed by default on the JSBoundFunction. It lazily
-  // computes the value from the underlying internal name.
-  LookupIterator name_lookup(target, isolate->factory()->name_string(), target,
-                             LookupIterator::OWN);
-  if (!target->IsJSFunction() ||
-      name_lookup.state() != LookupIterator::ACCESSOR ||
-      !name_lookup.GetAccessors()->IsAccessorInfo()) {
-    Handle<Object> target_name;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, target_name,
-                                       Object::GetProperty(&name_lookup));
-    Handle<String> name;
-    if (target_name->IsString()) {
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-          isolate, name,
-          Name::ToFunctionName(Handle<String>::cast(target_name)));
-      ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-          isolate, name, isolate->factory()->NewConsString(
-                             isolate->factory()->bound__string(), name));
-    } else {
-      name = isolate->factory()->bound__string();
-    }
-    LookupIterator it(function, isolate->factory()->name_string());
-    DCHECK_EQ(LookupIterator::ACCESSOR, it.state());
-    RETURN_FAILURE_ON_EXCEPTION(isolate,
-                                JSObject::DefineOwnPropertyIgnoreAttributes(
-                                    &it, name, it.property_attributes()));
-  }
-  return *function;
-}
-
-}  // namespace
-
-// ES6 section 19.2.3.2 Function.prototype.bind ( thisArg, ...args )
-BUILTIN(FunctionPrototypeBind) { return DoFunctionBind(isolate, args); }
-
-// TODO(verwaest): This is a temporary helper until the FastFunctionBind stub
-// can tailcall to the builtin directly.
-RUNTIME_FUNCTION(Runtime_FunctionBind) {
-  DCHECK_EQ(2, args.length());
-  Arguments* incoming = reinterpret_cast<Arguments*>(args[0]);
-  // Rewrap the arguments as builtins arguments.
-  int argc = incoming->length() + BuiltinArguments::kNumExtraArgsWithReceiver;
-  BuiltinArguments caller_args(argc, incoming->arguments() + 1);
-  return DoFunctionBind(isolate, caller_args);
-}
-
-// ES6 section 19.2.3.5 Function.prototype.toString ( )
-BUILTIN(FunctionPrototypeToString) {
-  HandleScope scope(isolate);
-  Handle<Object> receiver = args.receiver();
-  if (receiver->IsJSBoundFunction()) {
-    return *JSBoundFunction::ToString(Handle<JSBoundFunction>::cast(receiver));
-  } else if (receiver->IsJSFunction()) {
-    return *JSFunction::ToString(Handle<JSFunction>::cast(receiver));
-  }
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate, NewTypeError(MessageTemplate::kNotGeneric,
-                            isolate->factory()->NewStringFromAsciiChecked(
-                                "Function.prototype.toString")));
-}
-
-
-// ES6 section 25.2.1.1 GeneratorFunction (p1, p2, ... , pn, body)
-BUILTIN(GeneratorFunctionConstructor) {
-  HandleScope scope(isolate);
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           CreateDynamicFunction(isolate, args, "function*"));
-}
-
-BUILTIN(AsyncFunctionConstructor) {
-  HandleScope scope(isolate);
-  Handle<JSFunction> func;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, func, CreateDynamicFunction(isolate, args, "async function"));
-
-  // Do not lazily compute eval position for AsyncFunction, as they may not be
-  // determined after the function is resumed.
-  Handle<Script> script = handle(Script::cast(func->shared()->script()));
-  int position = script->GetEvalPosition();
-  USE(position);
-
-  return *func;
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 19.1 Object Objects
-
-// ES6 section 19.1.3.4 Object.prototype.propertyIsEnumerable ( V )
-BUILTIN(ObjectPrototypePropertyIsEnumerable) {
-  HandleScope scope(isolate);
-  Handle<JSReceiver> object;
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, name, Object::ToName(isolate, args.atOrUndefined(isolate, 1)));
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, object, JSReceiver::ToObject(isolate, args.receiver()));
-  Maybe<PropertyAttributes> maybe =
-      JSReceiver::GetOwnPropertyAttributes(object, name);
-  if (!maybe.IsJust()) return isolate->heap()->exception();
-  if (maybe.FromJust() == ABSENT) return isolate->heap()->false_value();
-  return isolate->heap()->ToBoolean((maybe.FromJust() & DONT_ENUM) == 0);
-}
-
-// ES6 section 19.1.3.6 Object.prototype.toString
-BUILTIN(ObjectProtoToString) {
-  HandleScope scope(isolate);
-  Handle<Object> object = args.at<Object>(0);
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           Object::ObjectProtoToString(isolate, object));
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 19.4 Symbol Objects
-
-// ES6 section 19.4.1.1 Symbol ( [ description ] ) for the [[Call]] case.
-BUILTIN(SymbolConstructor) {
-  HandleScope scope(isolate);
-  Handle<Symbol> result = isolate->factory()->NewSymbol();
-  Handle<Object> description = args.atOrUndefined(isolate, 1);
-  if (!description->IsUndefined(isolate)) {
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, description,
-                                       Object::ToString(isolate, description));
-    result->set_name(*description);
-  }
-  return *result;
-}
-
-
-// ES6 section 19.4.1.1 Symbol ( [ description ] ) for the [[Construct]] case.
-BUILTIN(SymbolConstructor_ConstructStub) {
-  HandleScope scope(isolate);
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate, NewTypeError(MessageTemplate::kNotConstructor,
-                            isolate->factory()->Symbol_string()));
-}
-
-// ES6 section 19.4.3.4 Symbol.prototype [ @@toPrimitive ] ( hint )
-void Builtins::Generate_SymbolPrototypeToPrimitive(
-    CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(4);
-
-  Node* result =
-      assembler->ToThisValue(context, receiver, PrimitiveType::kSymbol,
-                             "Symbol.prototype [ @@toPrimitive ]");
-  assembler->Return(result);
-}
-
-// ES6 section 19.4.3.2 Symbol.prototype.toString ( )
-void Builtins::Generate_SymbolPrototypeToString(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  Node* value = assembler->ToThisValue(
-      context, receiver, PrimitiveType::kSymbol, "Symbol.prototype.toString");
-  Node* result =
-      assembler->CallRuntime(Runtime::kSymbolDescriptiveString, context, value);
-  assembler->Return(result);
-}
-
-// ES6 section 19.4.3.3 Symbol.prototype.valueOf ( )
-void Builtins::Generate_SymbolPrototypeValueOf(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  Node* result = assembler->ToThisValue(
-      context, receiver, PrimitiveType::kSymbol, "Symbol.prototype.valueOf");
-  assembler->Return(result);
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 21.1 String Objects
-
-// ES6 section 21.1.2.1 String.fromCharCode ( ...codeUnits )
-void Builtins::Generate_StringFromCharCode(CodeStubAssembler* assembler) {
-  typedef CodeStubAssembler::Label Label;
-  typedef compiler::Node Node;
-  typedef CodeStubAssembler::Variable Variable;
-
-  Node* code = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-
-  // Check if we have exactly one argument (plus the implicit receiver), i.e.
-  // if the parent frame is not an arguments adaptor frame.
-  Label if_oneargument(assembler), if_notoneargument(assembler);
-  Node* parent_frame_pointer = assembler->LoadParentFramePointer();
-  Node* parent_frame_type =
-      assembler->Load(MachineType::Pointer(), parent_frame_pointer,
-                      assembler->IntPtrConstant(
-                          CommonFrameConstants::kContextOrFrameTypeOffset));
-  assembler->Branch(
-      assembler->WordEqual(
-          parent_frame_type,
-          assembler->SmiConstant(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR))),
-      &if_notoneargument, &if_oneargument);
-
-  assembler->Bind(&if_oneargument);
-  {
-    // Single argument case, perform fast single character string cache lookup
-    // for one-byte code units, or fall back to creating a single character
-    // string on the fly otherwise.
-    Node* code32 = assembler->TruncateTaggedToWord32(context, code);
-    Node* code16 = assembler->Word32And(
-        code32, assembler->Int32Constant(String::kMaxUtf16CodeUnit));
-    Node* result = assembler->StringFromCharCode(code16);
-    assembler->Return(result);
-  }
-
-  assembler->Bind(&if_notoneargument);
-  {
-    // Determine the resulting string length.
-    Node* parent_frame_length =
-        assembler->Load(MachineType::Pointer(), parent_frame_pointer,
-                        assembler->IntPtrConstant(
-                            ArgumentsAdaptorFrameConstants::kLengthOffset));
-    Node* length = assembler->SmiToWord(parent_frame_length);
-
-    // Assume that the resulting string contains only one-byte characters.
-    Node* result = assembler->AllocateSeqOneByteString(context, length);
-
-    // Truncate all input parameters and append them to the resulting string.
-    Variable var_offset(assembler, MachineType::PointerRepresentation());
-    Label loop(assembler, &var_offset), done_loop(assembler);
-    var_offset.Bind(assembler->IntPtrConstant(0));
-    assembler->Goto(&loop);
-    assembler->Bind(&loop);
-    {
-      // Load the current {offset}.
-      Node* offset = var_offset.value();
-
-      // Check if we're done with the string.
-      assembler->GotoIf(assembler->WordEqual(offset, length), &done_loop);
-
-      // Load the next code point and truncate it to a 16-bit value.
-      Node* code = assembler->Load(
-          MachineType::AnyTagged(), parent_frame_pointer,
-          assembler->IntPtrAdd(
-              assembler->WordShl(assembler->IntPtrSub(length, offset),
-                                 assembler->IntPtrConstant(kPointerSizeLog2)),
-              assembler->IntPtrConstant(
-                  CommonFrameConstants::kFixedFrameSizeAboveFp -
-                  kPointerSize)));
-      Node* code32 = assembler->TruncateTaggedToWord32(context, code);
-      Node* code16 = assembler->Word32And(
-          code32, assembler->Int32Constant(String::kMaxUtf16CodeUnit));
-
-      // Check if {code16} fits into a one-byte string.
-      Label if_codeisonebyte(assembler), if_codeistwobyte(assembler);
-      assembler->Branch(
-          assembler->Int32LessThanOrEqual(
-              code16, assembler->Int32Constant(String::kMaxOneByteCharCode)),
-          &if_codeisonebyte, &if_codeistwobyte);
-
-      assembler->Bind(&if_codeisonebyte);
-      {
-        // The {code16} fits into the SeqOneByteString {result}.
-        assembler->StoreNoWriteBarrier(
-            MachineRepresentation::kWord8, result,
-            assembler->IntPtrAdd(
-                assembler->IntPtrConstant(SeqOneByteString::kHeaderSize -
-                                          kHeapObjectTag),
-                offset),
-            code16);
-        var_offset.Bind(
-            assembler->IntPtrAdd(offset, assembler->IntPtrConstant(1)));
-        assembler->Goto(&loop);
-      }
-
-      assembler->Bind(&if_codeistwobyte);
-      {
-        // Allocate a SeqTwoByteString to hold the resulting string.
-        Node* cresult = assembler->AllocateSeqTwoByteString(context, length);
-
-        // Copy all characters that were previously written to the
-        // SeqOneByteString in {result} over to the new {cresult}.
-        Variable var_coffset(assembler, MachineType::PointerRepresentation());
-        Label cloop(assembler, &var_coffset), done_cloop(assembler);
-        var_coffset.Bind(assembler->IntPtrConstant(0));
-        assembler->Goto(&cloop);
-        assembler->Bind(&cloop);
-        {
-          Node* coffset = var_coffset.value();
-          assembler->GotoIf(assembler->WordEqual(coffset, offset), &done_cloop);
-          Node* ccode = assembler->Load(
-              MachineType::Uint8(), result,
-              assembler->IntPtrAdd(
-                  assembler->IntPtrConstant(SeqOneByteString::kHeaderSize -
-                                            kHeapObjectTag),
-                  coffset));
-          assembler->StoreNoWriteBarrier(
-              MachineRepresentation::kWord16, cresult,
-              assembler->IntPtrAdd(
-                  assembler->IntPtrConstant(SeqTwoByteString::kHeaderSize -
-                                            kHeapObjectTag),
-                  assembler->WordShl(coffset, 1)),
-              ccode);
-          var_coffset.Bind(
-              assembler->IntPtrAdd(coffset, assembler->IntPtrConstant(1)));
-          assembler->Goto(&cloop);
-        }
-
-        // Write the pending {code16} to {offset}.
-        assembler->Bind(&done_cloop);
-        assembler->StoreNoWriteBarrier(
-            MachineRepresentation::kWord16, cresult,
-            assembler->IntPtrAdd(
-                assembler->IntPtrConstant(SeqTwoByteString::kHeaderSize -
-                                          kHeapObjectTag),
-                assembler->WordShl(offset, 1)),
-            code16);
-
-        // Copy the remaining parameters to the SeqTwoByteString {cresult}.
-        Label floop(assembler, &var_offset), done_floop(assembler);
-        assembler->Goto(&floop);
-        assembler->Bind(&floop);
-        {
-          // Compute the next {offset}.
-          Node* offset = assembler->IntPtrAdd(var_offset.value(),
-                                              assembler->IntPtrConstant(1));
-
-          // Check if we're done with the string.
-          assembler->GotoIf(assembler->WordEqual(offset, length), &done_floop);
-
-          // Load the next code point and truncate it to a 16-bit value.
-          Node* code = assembler->Load(
-              MachineType::AnyTagged(), parent_frame_pointer,
-              assembler->IntPtrAdd(
-                  assembler->WordShl(
-                      assembler->IntPtrSub(length, offset),
-                      assembler->IntPtrConstant(kPointerSizeLog2)),
-                  assembler->IntPtrConstant(
-                      CommonFrameConstants::kFixedFrameSizeAboveFp -
-                      kPointerSize)));
-          Node* code32 = assembler->TruncateTaggedToWord32(context, code);
-          Node* code16 = assembler->Word32And(
-              code32, assembler->Int32Constant(String::kMaxUtf16CodeUnit));
-
-          // Store the truncated {code} point at the next offset.
-          assembler->StoreNoWriteBarrier(
-              MachineRepresentation::kWord16, cresult,
-              assembler->IntPtrAdd(
-                  assembler->IntPtrConstant(SeqTwoByteString::kHeaderSize -
-                                            kHeapObjectTag),
-                  assembler->WordShl(offset, 1)),
-              code16);
-          var_offset.Bind(offset);
-          assembler->Goto(&floop);
-        }
-
-        // Return the SeqTwoByteString.
-        assembler->Bind(&done_floop);
-        assembler->Return(cresult);
-      }
-    }
-
-    assembler->Bind(&done_loop);
-    assembler->Return(result);
-  }
-}
-
-namespace {  // for String.fromCodePoint
-
-bool IsValidCodePoint(Isolate* isolate, Handle<Object> value) {
-  if (!value->IsNumber() && !Object::ToNumber(value).ToHandle(&value)) {
-    return false;
-  }
-
-  if (Object::ToInteger(isolate, value).ToHandleChecked()->Number() !=
-      value->Number()) {
-    return false;
-  }
-
-  if (value->Number() < 0 || value->Number() > 0x10FFFF) {
-    return false;
-  }
-
-  return true;
-}
-
-uc32 NextCodePoint(Isolate* isolate, BuiltinArguments args, int index) {
-  Handle<Object> value = args.at<Object>(1 + index);
-  ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, value, Object::ToNumber(value), -1);
-  if (!IsValidCodePoint(isolate, value)) {
-    isolate->Throw(*isolate->factory()->NewRangeError(
-        MessageTemplate::kInvalidCodePoint, value));
-    return -1;
-  }
-  return DoubleToUint32(value->Number());
-}
-
-}  // namespace
-
-// ES6 section 21.1.2.2 String.fromCodePoint ( ...codePoints )
-BUILTIN(StringFromCodePoint) {
-  HandleScope scope(isolate);
-  int const length = args.length() - 1;
-  if (length == 0) return isolate->heap()->empty_string();
-  DCHECK_LT(0, length);
-
-  // Optimistically assume that the resulting String contains only one byte
-  // characters.
-  List<uint8_t> one_byte_buffer(length);
-  uc32 code = 0;
-  int index;
-  for (index = 0; index < length; index++) {
-    code = NextCodePoint(isolate, args, index);
-    if (code < 0) {
-      return isolate->heap()->exception();
-    }
-    if (code > String::kMaxOneByteCharCode) {
-      break;
-    }
-    one_byte_buffer.Add(code);
-  }
-
-  if (index == length) {
-    RETURN_RESULT_OR_FAILURE(isolate, isolate->factory()->NewStringFromOneByte(
-                                          one_byte_buffer.ToConstVector()));
-  }
-
-  List<uc16> two_byte_buffer(length - index);
-
-  while (true) {
-    if (code <= unibrow::Utf16::kMaxNonSurrogateCharCode) {
-      two_byte_buffer.Add(code);
-    } else {
-      two_byte_buffer.Add(unibrow::Utf16::LeadSurrogate(code));
-      two_byte_buffer.Add(unibrow::Utf16::TrailSurrogate(code));
-    }
-
-    if (++index == length) {
-      break;
-    }
-    code = NextCodePoint(isolate, args, index);
-    if (code < 0) {
-      return isolate->heap()->exception();
-    }
-  }
-
-  Handle<SeqTwoByteString> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, result,
-      isolate->factory()->NewRawTwoByteString(one_byte_buffer.length() +
-                                              two_byte_buffer.length()));
-
-  CopyChars(result->GetChars(), one_byte_buffer.ToConstVector().start(),
-            one_byte_buffer.length());
-  CopyChars(result->GetChars() + one_byte_buffer.length(),
-            two_byte_buffer.ToConstVector().start(), two_byte_buffer.length());
-
-  return *result;
-}
-
-// ES6 section 21.1.3.1 String.prototype.charAt ( pos )
-void Builtins::Generate_StringPrototypeCharAt(CodeStubAssembler* assembler) {
-  typedef CodeStubAssembler::Label Label;
-  typedef compiler::Node Node;
-  typedef CodeStubAssembler::Variable Variable;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* position = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-
-  // Check that {receiver} is coercible to Object and convert it to a String.
-  receiver =
-      assembler->ToThisString(context, receiver, "String.prototype.charAt");
-
-  // Convert the {position} to a Smi and check that it's in bounds of the
-  // {receiver}.
-  // TODO(bmeurer): Find an abstraction for this!
-  {
-    // Check if the {position} is already a Smi.
-    Variable var_position(assembler, MachineRepresentation::kTagged);
-    var_position.Bind(position);
-    Label if_positionissmi(assembler),
-        if_positionisnotsmi(assembler, Label::kDeferred);
-    assembler->Branch(assembler->WordIsSmi(position), &if_positionissmi,
-                      &if_positionisnotsmi);
-    assembler->Bind(&if_positionisnotsmi);
-    {
-      // Convert the {position} to an Integer via the ToIntegerStub.
-      Callable callable = CodeFactory::ToInteger(assembler->isolate());
-      Node* index = assembler->CallStub(callable, context, position);
-
-      // Check if the resulting {index} is now a Smi.
-      Label if_indexissmi(assembler, Label::kDeferred),
-          if_indexisnotsmi(assembler, Label::kDeferred);
-      assembler->Branch(assembler->WordIsSmi(index), &if_indexissmi,
-                        &if_indexisnotsmi);
-
-      assembler->Bind(&if_indexissmi);
-      {
-        var_position.Bind(index);
-        assembler->Goto(&if_positionissmi);
-      }
-
-      assembler->Bind(&if_indexisnotsmi);
-      {
-        // The ToIntegerStub canonicalizes everything in Smi range to Smi
-        // representation, so any HeapNumber returned is not in Smi range.
-        // The only exception here is -0.0, which we treat as 0.
-        Node* index_value = assembler->LoadHeapNumberValue(index);
-        Label if_indexiszero(assembler, Label::kDeferred),
-            if_indexisnotzero(assembler, Label::kDeferred);
-        assembler->Branch(assembler->Float64Equal(
-                              index_value, assembler->Float64Constant(0.0)),
-                          &if_indexiszero, &if_indexisnotzero);
-
-        assembler->Bind(&if_indexiszero);
-        {
-          var_position.Bind(assembler->SmiConstant(Smi::FromInt(0)));
-          assembler->Goto(&if_positionissmi);
-        }
-
-        assembler->Bind(&if_indexisnotzero);
-        {
-          // The {index} is some other integral Number, that is definitely
-          // neither -0.0 nor in Smi range.
-          assembler->Return(assembler->EmptyStringConstant());
-        }
-      }
-    }
-    assembler->Bind(&if_positionissmi);
-    position = var_position.value();
-
-    // Determine the actual length of the {receiver} String.
-    Node* receiver_length =
-        assembler->LoadObjectField(receiver, String::kLengthOffset);
-
-    // Return "" if the Smi {position} is outside the bounds of the {receiver}.
-    Label if_positioninbounds(assembler),
-        if_positionnotinbounds(assembler, Label::kDeferred);
-    assembler->Branch(assembler->SmiAboveOrEqual(position, receiver_length),
-                      &if_positionnotinbounds, &if_positioninbounds);
-    assembler->Bind(&if_positionnotinbounds);
-    assembler->Return(assembler->EmptyStringConstant());
-    assembler->Bind(&if_positioninbounds);
-  }
-
-  // Load the character code at the {position} from the {receiver}.
-  Node* code = assembler->StringCharCodeAt(receiver, position);
-
-  // And return the single character string with only that {code}.
-  Node* result = assembler->StringFromCharCode(code);
-  assembler->Return(result);
-}
-
-// ES6 section 21.1.3.2 String.prototype.charCodeAt ( pos )
-void Builtins::Generate_StringPrototypeCharCodeAt(
-    CodeStubAssembler* assembler) {
-  typedef CodeStubAssembler::Label Label;
-  typedef compiler::Node Node;
-  typedef CodeStubAssembler::Variable Variable;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* position = assembler->Parameter(1);
-  Node* context = assembler->Parameter(4);
-
-  // Check that {receiver} is coercible to Object and convert it to a String.
-  receiver =
-      assembler->ToThisString(context, receiver, "String.prototype.charCodeAt");
-
-  // Convert the {position} to a Smi and check that it's in bounds of the
-  // {receiver}.
-  // TODO(bmeurer): Find an abstraction for this!
-  {
-    // Check if the {position} is already a Smi.
-    Variable var_position(assembler, MachineRepresentation::kTagged);
-    var_position.Bind(position);
-    Label if_positionissmi(assembler),
-        if_positionisnotsmi(assembler, Label::kDeferred);
-    assembler->Branch(assembler->WordIsSmi(position), &if_positionissmi,
-                      &if_positionisnotsmi);
-    assembler->Bind(&if_positionisnotsmi);
-    {
-      // Convert the {position} to an Integer via the ToIntegerStub.
-      Callable callable = CodeFactory::ToInteger(assembler->isolate());
-      Node* index = assembler->CallStub(callable, context, position);
-
-      // Check if the resulting {index} is now a Smi.
-      Label if_indexissmi(assembler, Label::kDeferred),
-          if_indexisnotsmi(assembler, Label::kDeferred);
-      assembler->Branch(assembler->WordIsSmi(index), &if_indexissmi,
-                        &if_indexisnotsmi);
-
-      assembler->Bind(&if_indexissmi);
-      {
-        var_position.Bind(index);
-        assembler->Goto(&if_positionissmi);
-      }
-
-      assembler->Bind(&if_indexisnotsmi);
-      {
-        // The ToIntegerStub canonicalizes everything in Smi range to Smi
-        // representation, so any HeapNumber returned is not in Smi range.
-        // The only exception here is -0.0, which we treat as 0.
-        Node* index_value = assembler->LoadHeapNumberValue(index);
-        Label if_indexiszero(assembler, Label::kDeferred),
-            if_indexisnotzero(assembler, Label::kDeferred);
-        assembler->Branch(assembler->Float64Equal(
-                              index_value, assembler->Float64Constant(0.0)),
-                          &if_indexiszero, &if_indexisnotzero);
-
-        assembler->Bind(&if_indexiszero);
-        {
-          var_position.Bind(assembler->SmiConstant(Smi::FromInt(0)));
-          assembler->Goto(&if_positionissmi);
-        }
-
-        assembler->Bind(&if_indexisnotzero);
-        {
-          // The {index} is some other integral Number, that is definitely
-          // neither -0.0 nor in Smi range.
-          assembler->Return(assembler->NaNConstant());
-        }
-      }
-    }
-    assembler->Bind(&if_positionissmi);
-    position = var_position.value();
-
-    // Determine the actual length of the {receiver} String.
-    Node* receiver_length =
-        assembler->LoadObjectField(receiver, String::kLengthOffset);
-
-    // Return NaN if the Smi {position} is outside the bounds of the {receiver}.
-    Label if_positioninbounds(assembler),
-        if_positionnotinbounds(assembler, Label::kDeferred);
-    assembler->Branch(assembler->SmiAboveOrEqual(position, receiver_length),
-                      &if_positionnotinbounds, &if_positioninbounds);
-    assembler->Bind(&if_positionnotinbounds);
-    assembler->Return(assembler->NaNConstant());
-    assembler->Bind(&if_positioninbounds);
-  }
-
-  // Load the character at the {position} from the {receiver}.
-  Node* value = assembler->StringCharCodeAt(receiver, position);
-  Node* result = assembler->SmiFromWord32(value);
-  assembler->Return(result);
-}
-
-// ES6 section 21.1.3.25 String.prototype.toString ()
-void Builtins::Generate_StringPrototypeToString(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  Node* result = assembler->ToThisValue(
-      context, receiver, PrimitiveType::kString, "String.prototype.toString");
-  assembler->Return(result);
-}
-
-// ES6 section 21.1.3.27 String.prototype.trim ()
-BUILTIN(StringPrototypeTrim) {
-  HandleScope scope(isolate);
-  TO_THIS_STRING(string, "String.prototype.trim");
-  return *String::Trim(string, String::kTrim);
-}
-
-// Non-standard WebKit extension
-BUILTIN(StringPrototypeTrimLeft) {
-  HandleScope scope(isolate);
-  TO_THIS_STRING(string, "String.prototype.trimLeft");
-  return *String::Trim(string, String::kTrimLeft);
-}
-
-// Non-standard WebKit extension
-BUILTIN(StringPrototypeTrimRight) {
-  HandleScope scope(isolate);
-  TO_THIS_STRING(string, "String.prototype.trimRight");
-  return *String::Trim(string, String::kTrimRight);
-}
-
-// ES6 section 21.1.3.28 String.prototype.valueOf ( )
-void Builtins::Generate_StringPrototypeValueOf(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* context = assembler->Parameter(3);
-
-  Node* result = assembler->ToThisValue(
-      context, receiver, PrimitiveType::kString, "String.prototype.valueOf");
-  assembler->Return(result);
-}
-
-// -----------------------------------------------------------------------------
-// ES6 section 21.1 ArrayBuffer Objects
-
-// ES6 section 24.1.2.1 ArrayBuffer ( length ) for the [[Call]] case.
-BUILTIN(ArrayBufferConstructor) {
-  HandleScope scope(isolate);
-  Handle<JSFunction> target = args.target<JSFunction>();
-  DCHECK(*target == target->native_context()->array_buffer_fun() ||
-         *target == target->native_context()->shared_array_buffer_fun());
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate, NewTypeError(MessageTemplate::kConstructorNotFunction,
-                            handle(target->shared()->name(), isolate)));
-}
-
-
-// ES6 section 24.1.2.1 ArrayBuffer ( length ) for the [[Construct]] case.
-BUILTIN(ArrayBufferConstructor_ConstructStub) {
-  HandleScope scope(isolate);
-  Handle<JSFunction> target = args.target<JSFunction>();
-  Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
-  Handle<Object> length = args.atOrUndefined(isolate, 1);
-  DCHECK(*target == target->native_context()->array_buffer_fun() ||
-         *target == target->native_context()->shared_array_buffer_fun());
-  Handle<Object> number_length;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, number_length,
-                                     Object::ToInteger(isolate, length));
-  if (number_length->Number() < 0.0) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kInvalidArrayBufferLength));
-  }
-  Handle<JSObject> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
-                                     JSObject::New(target, new_target));
-  size_t byte_length;
-  if (!TryNumberToSize(isolate, *number_length, &byte_length)) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kInvalidArrayBufferLength));
-  }
-  SharedFlag shared_flag =
-      (*target == target->native_context()->array_buffer_fun())
-          ? SharedFlag::kNotShared
-          : SharedFlag::kShared;
-  if (!JSArrayBuffer::SetupAllocatingData(Handle<JSArrayBuffer>::cast(result),
-                                          isolate, byte_length, true,
-                                          shared_flag)) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kArrayBufferAllocationFailed));
-  }
-  return *result;
-}
-
-// ES6 section 24.1.4.1 get ArrayBuffer.prototype.byteLength
-BUILTIN(ArrayBufferPrototypeGetByteLength) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSArrayBuffer, array_buffer,
-                 "get ArrayBuffer.prototype.byteLength");
-
-  if (array_buffer->is_shared()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kIncompatibleMethodReceiver,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "get ArrayBuffer.prototype.byteLength"),
-                              args.receiver()));
-  }
-  // TODO(franzih): According to the ES6 spec, we should throw a TypeError
-  // here if the JSArrayBuffer is detached.
-  return array_buffer->byte_length();
-}
-
-// ES6 section 24.1.3.1 ArrayBuffer.isView ( arg )
-BUILTIN(ArrayBufferIsView) {
-  SealHandleScope shs(isolate);
-  DCHECK_EQ(2, args.length());
-  Object* arg = args[1];
-  return isolate->heap()->ToBoolean(arg->IsJSArrayBufferView());
-}
-
-// ES7 sharedmem 6.3.4.1 get SharedArrayBuffer.prototype.byteLength
-BUILTIN(SharedArrayBufferPrototypeGetByteLength) {
-  HandleScope scope(isolate);
-  CHECK_RECEIVER(JSArrayBuffer, array_buffer,
-                 "get SharedArrayBuffer.prototype.byteLength");
-  if (!array_buffer->is_shared()) {
-    THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewTypeError(MessageTemplate::kIncompatibleMethodReceiver,
-                              isolate->factory()->NewStringFromAsciiChecked(
-                                  "get SharedArrayBuffer.prototype.byteLength"),
-                              args.receiver()));
-  }
-  return array_buffer->byte_length();
-}
-
-// ES6 section 26.2.1.1 Proxy ( target, handler ) for the [[Call]] case.
-BUILTIN(ProxyConstructor) {
-  HandleScope scope(isolate);
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate,
-      NewTypeError(MessageTemplate::kConstructorNotFunction,
-                   isolate->factory()->NewStringFromAsciiChecked("Proxy")));
-}
-
-
-// ES6 section 26.2.1.1 Proxy ( target, handler ) for the [[Construct]] case.
-BUILTIN(ProxyConstructor_ConstructStub) {
-  HandleScope scope(isolate);
-  DCHECK(isolate->proxy_function()->IsConstructor());
-  Handle<Object> target = args.atOrUndefined(isolate, 1);
-  Handle<Object> handler = args.atOrUndefined(isolate, 2);
-  RETURN_RESULT_OR_FAILURE(isolate, JSProxy::New(isolate, target, handler));
-}
-
-
-// -----------------------------------------------------------------------------
-// Throwers for restricted function properties and strict arguments object
-// properties
-
-
-BUILTIN(RestrictedFunctionPropertiesThrower) {
-  HandleScope scope(isolate);
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate, NewTypeError(MessageTemplate::kRestrictedFunctionProperties));
-}
-
-
-BUILTIN(RestrictedStrictArgumentsPropertiesThrower) {
-  HandleScope scope(isolate);
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate, NewTypeError(MessageTemplate::kStrictPoisonPill));
-}
-
-
-// -----------------------------------------------------------------------------
-//
-
-
-namespace {
-
-// Returns the holder JSObject if the function can legally be called with this
-// receiver.  Returns nullptr if the call is illegal.
-// TODO(dcarney): CallOptimization duplicates this logic, merge.
-JSObject* GetCompatibleReceiver(Isolate* isolate, FunctionTemplateInfo* info,
-                                JSObject* receiver) {
-  Object* recv_type = info->signature();
-  // No signature, return holder.
-  if (!recv_type->IsFunctionTemplateInfo()) return receiver;
-  FunctionTemplateInfo* signature = FunctionTemplateInfo::cast(recv_type);
-
-  // Check the receiver. Fast path for receivers with no hidden prototypes.
-  if (signature->IsTemplateFor(receiver)) return receiver;
-  if (!receiver->map()->has_hidden_prototype()) return nullptr;
-  for (PrototypeIterator iter(isolate, receiver, kStartAtPrototype,
-                              PrototypeIterator::END_AT_NON_HIDDEN);
-       !iter.IsAtEnd(); iter.Advance()) {
-    JSObject* current = iter.GetCurrent<JSObject>();
-    if (signature->IsTemplateFor(current)) return current;
-  }
-  return nullptr;
-}
-
-template <bool is_construct>
-MUST_USE_RESULT MaybeHandle<Object> HandleApiCallHelper(
-    Isolate* isolate, Handle<HeapObject> function,
-    Handle<HeapObject> new_target, Handle<FunctionTemplateInfo> fun_data,
-    Handle<Object> receiver, BuiltinArguments args) {
-  Handle<JSObject> js_receiver;
-  JSObject* raw_holder;
-  if (is_construct) {
-    DCHECK(args.receiver()->IsTheHole(isolate));
-    if (fun_data->instance_template()->IsUndefined(isolate)) {
-      v8::Local<ObjectTemplate> templ =
-          ObjectTemplate::New(reinterpret_cast<v8::Isolate*>(isolate),
-                              ToApiHandle<v8::FunctionTemplate>(fun_data));
-      fun_data->set_instance_template(*Utils::OpenHandle(*templ));
-    }
-    Handle<ObjectTemplateInfo> instance_template(
-        ObjectTemplateInfo::cast(fun_data->instance_template()), isolate);
-    ASSIGN_RETURN_ON_EXCEPTION(
-        isolate, js_receiver,
-        ApiNatives::InstantiateObject(instance_template,
-                                      Handle<JSReceiver>::cast(new_target)),
-        Object);
-    args[0] = *js_receiver;
-    DCHECK_EQ(*js_receiver, *args.receiver());
-
-    raw_holder = *js_receiver;
-  } else {
-    DCHECK(receiver->IsJSReceiver());
-
-    if (!receiver->IsJSObject()) {
-      // This function cannot be called with the given receiver.  Abort!
-      THROW_NEW_ERROR(
-          isolate, NewTypeError(MessageTemplate::kIllegalInvocation), Object);
-    }
-
-    js_receiver = Handle<JSObject>::cast(receiver);
-
-    if (!fun_data->accept_any_receiver() &&
-        js_receiver->IsAccessCheckNeeded() &&
-        !isolate->MayAccess(handle(isolate->context()), js_receiver)) {
-      isolate->ReportFailedAccessCheck(js_receiver);
-      RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
-    }
-
-    raw_holder = GetCompatibleReceiver(isolate, *fun_data, *js_receiver);
-
-    if (raw_holder == nullptr) {
-      // This function cannot be called with the given receiver.  Abort!
-      THROW_NEW_ERROR(
-          isolate, NewTypeError(MessageTemplate::kIllegalInvocation), Object);
-    }
-  }
-
-  Object* raw_call_data = fun_data->call_code();
-  if (!raw_call_data->IsUndefined(isolate)) {
-    DCHECK(raw_call_data->IsCallHandlerInfo());
-    CallHandlerInfo* call_data = CallHandlerInfo::cast(raw_call_data);
-    Object* callback_obj = call_data->callback();
-    v8::FunctionCallback callback =
-        v8::ToCData<v8::FunctionCallback>(callback_obj);
-    Object* data_obj = call_data->data();
-
-    LOG(isolate, ApiObjectAccess("call", JSObject::cast(*js_receiver)));
-
-    FunctionCallbackArguments custom(isolate, data_obj, *function, raw_holder,
-                                     *new_target, &args[0] - 1,
-                                     args.length() - 1);
-
-    Handle<Object> result = custom.Call(callback);
-
-    RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
-    if (result.is_null()) {
-      if (is_construct) return js_receiver;
-      return isolate->factory()->undefined_value();
-    }
-    // Rebox the result.
-    result->VerifyApiCallResultType();
-    if (!is_construct || result->IsJSObject()) return handle(*result, isolate);
-  }
-
-  return js_receiver;
-}
-
-}  // namespace
-
-
-BUILTIN(HandleApiCall) {
-  HandleScope scope(isolate);
-  Handle<JSFunction> function = args.target<JSFunction>();
-  Handle<Object> receiver = args.receiver();
-  Handle<HeapObject> new_target = args.new_target();
-  Handle<FunctionTemplateInfo> fun_data(function->shared()->get_api_func_data(),
-                                        isolate);
-  if (new_target->IsJSReceiver()) {
-    RETURN_RESULT_OR_FAILURE(
-        isolate, HandleApiCallHelper<true>(isolate, function, new_target,
-                                           fun_data, receiver, args));
-  } else {
-    RETURN_RESULT_OR_FAILURE(
-        isolate, HandleApiCallHelper<false>(isolate, function, new_target,
-                                            fun_data, receiver, args));
-  }
-}
-
-
-Handle<Code> Builtins::CallFunction(ConvertReceiverMode mode,
-                                    TailCallMode tail_call_mode) {
-  switch (tail_call_mode) {
-    case TailCallMode::kDisallow:
-      switch (mode) {
-        case ConvertReceiverMode::kNullOrUndefined:
-          return CallFunction_ReceiverIsNullOrUndefined();
-        case ConvertReceiverMode::kNotNullOrUndefined:
-          return CallFunction_ReceiverIsNotNullOrUndefined();
-        case ConvertReceiverMode::kAny:
-          return CallFunction_ReceiverIsAny();
-      }
-      break;
-    case TailCallMode::kAllow:
-      switch (mode) {
-        case ConvertReceiverMode::kNullOrUndefined:
-          return TailCallFunction_ReceiverIsNullOrUndefined();
-        case ConvertReceiverMode::kNotNullOrUndefined:
-          return TailCallFunction_ReceiverIsNotNullOrUndefined();
-        case ConvertReceiverMode::kAny:
-          return TailCallFunction_ReceiverIsAny();
-      }
-      break;
-  }
-  UNREACHABLE();
-  return Handle<Code>::null();
-}
-
-Handle<Code> Builtins::Call(ConvertReceiverMode mode,
-                            TailCallMode tail_call_mode) {
-  switch (tail_call_mode) {
-    case TailCallMode::kDisallow:
-      switch (mode) {
-        case ConvertReceiverMode::kNullOrUndefined:
-          return Call_ReceiverIsNullOrUndefined();
-        case ConvertReceiverMode::kNotNullOrUndefined:
-          return Call_ReceiverIsNotNullOrUndefined();
-        case ConvertReceiverMode::kAny:
-          return Call_ReceiverIsAny();
-      }
-      break;
-    case TailCallMode::kAllow:
-      switch (mode) {
-        case ConvertReceiverMode::kNullOrUndefined:
-          return TailCall_ReceiverIsNullOrUndefined();
-        case ConvertReceiverMode::kNotNullOrUndefined:
-          return TailCall_ReceiverIsNotNullOrUndefined();
-        case ConvertReceiverMode::kAny:
-          return TailCall_ReceiverIsAny();
-      }
-      break;
-  }
-  UNREACHABLE();
-  return Handle<Code>::null();
-}
-
-Handle<Code> Builtins::CallBoundFunction(TailCallMode tail_call_mode) {
-  switch (tail_call_mode) {
-    case TailCallMode::kDisallow:
-      return CallBoundFunction();
-    case TailCallMode::kAllow:
-      return TailCallBoundFunction();
-  }
-  UNREACHABLE();
-  return Handle<Code>::null();
-}
-
-Handle<Code> Builtins::InterpreterPushArgsAndCall(TailCallMode tail_call_mode,
-                                                  CallableType function_type) {
-  switch (tail_call_mode) {
-    case TailCallMode::kDisallow:
-      if (function_type == CallableType::kJSFunction) {
-        return InterpreterPushArgsAndCallFunction();
-      } else {
-        return InterpreterPushArgsAndCall();
-      }
-    case TailCallMode::kAllow:
-      if (function_type == CallableType::kJSFunction) {
-        return InterpreterPushArgsAndTailCallFunction();
-      } else {
-        return InterpreterPushArgsAndTailCall();
-      }
-  }
-  UNREACHABLE();
-  return Handle<Code>::null();
-}
-
-namespace {
-
-class RelocatableArguments : public BuiltinArguments, public Relocatable {
- public:
-  RelocatableArguments(Isolate* isolate, int length, Object** arguments)
-      : BuiltinArguments(length, arguments), Relocatable(isolate) {}
-
-  virtual inline void IterateInstance(ObjectVisitor* v) {
-    if (length() == 0) return;
-    v->VisitPointers(lowest_address(), highest_address() + 1);
-  }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(RelocatableArguments);
-};
-
-}  // namespace
-
-MaybeHandle<Object> Builtins::InvokeApiFunction(Isolate* isolate,
-                                                Handle<HeapObject> function,
-                                                Handle<Object> receiver,
-                                                int argc,
-                                                Handle<Object> args[]) {
-  DCHECK(function->IsFunctionTemplateInfo() ||
-         (function->IsJSFunction() &&
-          JSFunction::cast(*function)->shared()->IsApiFunction()));
-
-  // Do proper receiver conversion for non-strict mode api functions.
-  if (!receiver->IsJSReceiver()) {
-    if (function->IsFunctionTemplateInfo() ||
-        is_sloppy(JSFunction::cast(*function)->shared()->language_mode())) {
-      ASSIGN_RETURN_ON_EXCEPTION(isolate, receiver,
-                                 Object::ConvertReceiver(isolate, receiver),
-                                 Object);
-    }
-  }
-
-  Handle<FunctionTemplateInfo> fun_data =
-      function->IsFunctionTemplateInfo()
-          ? Handle<FunctionTemplateInfo>::cast(function)
-          : handle(JSFunction::cast(*function)->shared()->get_api_func_data(),
-                   isolate);
-  Handle<HeapObject> new_target = isolate->factory()->undefined_value();
-  // Construct BuiltinArguments object:
-  // new target, function, arguments reversed, receiver.
-  const int kBufferSize = 32;
-  Object* small_argv[kBufferSize];
-  Object** argv;
-  const int frame_argc = argc + BuiltinArguments::kNumExtraArgsWithReceiver;
-  if (frame_argc <= kBufferSize) {
-    argv = small_argv;
-  } else {
-    argv = new Object*[frame_argc];
-  }
-  int cursor = frame_argc - 1;
-  argv[cursor--] = *receiver;
-  for (int i = 0; i < argc; ++i) {
-    argv[cursor--] = *args[i];
-  }
-  DCHECK(cursor == BuiltinArguments::kArgcOffset);
-  argv[BuiltinArguments::kArgcOffset] = Smi::FromInt(frame_argc);
-  argv[BuiltinArguments::kTargetOffset] = *function;
-  argv[BuiltinArguments::kNewTargetOffset] = *new_target;
-  MaybeHandle<Object> result;
-  {
-    RelocatableArguments arguments(isolate, frame_argc, &argv[frame_argc - 1]);
-    result = HandleApiCallHelper<false>(isolate, function, new_target, fun_data,
-                                        receiver, arguments);
-  }
-  if (argv != small_argv) delete[] argv;
-  return result;
-}
-
-
-// Helper function to handle calls to non-function objects created through the
-// API. The object can be called as either a constructor (using new) or just as
-// a function (without new).
-MUST_USE_RESULT static Object* HandleApiCallAsFunctionOrConstructor(
-    Isolate* isolate, bool is_construct_call, BuiltinArguments args) {
-  Handle<Object> receiver = args.receiver();
-
-  // Get the object called.
-  JSObject* obj = JSObject::cast(*receiver);
-
-  // Set the new target.
-  HeapObject* new_target;
-  if (is_construct_call) {
-    // TODO(adamk): This should be passed through in args instead of
-    // being patched in here. We need to set a non-undefined value
-    // for v8::FunctionCallbackInfo::IsConstructCall() to get the
-    // right answer.
-    new_target = obj;
-  } else {
-    new_target = isolate->heap()->undefined_value();
-  }
-
-  // Get the invocation callback from the function descriptor that was
-  // used to create the called object.
-  DCHECK(obj->map()->is_callable());
-  JSFunction* constructor = JSFunction::cast(obj->map()->GetConstructor());
-  // TODO(ishell): turn this back to a DCHECK.
-  CHECK(constructor->shared()->IsApiFunction());
-  Object* handler =
-      constructor->shared()->get_api_func_data()->instance_call_handler();
-  DCHECK(!handler->IsUndefined(isolate));
-  // TODO(ishell): remove this debugging code.
-  CHECK(handler->IsCallHandlerInfo());
-  CallHandlerInfo* call_data = CallHandlerInfo::cast(handler);
-  Object* callback_obj = call_data->callback();
-  v8::FunctionCallback callback =
-      v8::ToCData<v8::FunctionCallback>(callback_obj);
-
-  // Get the data for the call and perform the callback.
-  Object* result;
-  {
-    HandleScope scope(isolate);
-    LOG(isolate, ApiObjectAccess("call non-function", obj));
-
-    FunctionCallbackArguments custom(isolate, call_data->data(), constructor,
-                                     obj, new_target, &args[0] - 1,
-                                     args.length() - 1);
-    Handle<Object> result_handle = custom.Call(callback);
-    if (result_handle.is_null()) {
-      result = isolate->heap()->undefined_value();
-    } else {
-      result = *result_handle;
-    }
-  }
-  // Check for exceptions and return result.
-  RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
-  return result;
-}
-
-
-// Handle calls to non-function objects created through the API. This delegate
-// function is used when the call is a normal function call.
-BUILTIN(HandleApiCallAsFunction) {
-  return HandleApiCallAsFunctionOrConstructor(isolate, false, args);
-}
-
-
-// Handle calls to non-function objects created through the API. This delegate
-// function is used when the call is a construct call.
-BUILTIN(HandleApiCallAsConstructor) {
-  return HandleApiCallAsFunctionOrConstructor(isolate, true, args);
-}
-
-namespace {
-
-void Generate_LoadIC_Miss(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* name = assembler->Parameter(1);
-  Node* slot = assembler->Parameter(2);
-  Node* vector = assembler->Parameter(3);
-  Node* context = assembler->Parameter(4);
-
-  assembler->TailCallRuntime(Runtime::kLoadIC_Miss, context, receiver, name,
-                             slot, vector);
-}
-
-void Generate_LoadGlobalIC_Miss(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* slot = assembler->Parameter(0);
-  Node* vector = assembler->Parameter(1);
-  Node* context = assembler->Parameter(2);
-
-  assembler->TailCallRuntime(Runtime::kLoadGlobalIC_Miss, context, slot,
-                             vector);
-}
-
-void Generate_LoadIC_Normal(MacroAssembler* masm) {
-  LoadIC::GenerateNormal(masm);
-}
-
-void Generate_LoadIC_Getter_ForDeopt(MacroAssembler* masm) {
-  NamedLoadHandlerCompiler::GenerateLoadViaGetterForDeopt(masm);
-}
-
-void Generate_LoadIC_Slow(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* name = assembler->Parameter(1);
-  // Node* slot = assembler->Parameter(2);
-  // Node* vector = assembler->Parameter(3);
-  Node* context = assembler->Parameter(4);
-
-  assembler->TailCallRuntime(Runtime::kGetProperty, context, receiver, name);
-}
-
-void Generate_LoadGlobalIC_Slow(CodeStubAssembler* assembler, TypeofMode mode) {
-  typedef compiler::Node Node;
-
-  Node* slot = assembler->Parameter(0);
-  Node* vector = assembler->Parameter(1);
-  Node* context = assembler->Parameter(2);
-  Node* typeof_mode = assembler->SmiConstant(Smi::FromInt(mode));
-
-  assembler->TailCallRuntime(Runtime::kGetGlobal, context, slot, vector,
-                             typeof_mode);
-}
-
-void Generate_LoadGlobalIC_SlowInsideTypeof(CodeStubAssembler* assembler) {
-  Generate_LoadGlobalIC_Slow(assembler, INSIDE_TYPEOF);
-}
-
-void Generate_LoadGlobalIC_SlowNotInsideTypeof(CodeStubAssembler* assembler) {
-  Generate_LoadGlobalIC_Slow(assembler, NOT_INSIDE_TYPEOF);
-}
-
-void Generate_KeyedLoadIC_Slow(MacroAssembler* masm) {
-  KeyedLoadIC::GenerateRuntimeGetProperty(masm);
-}
-
-void Generate_KeyedLoadIC_Miss(MacroAssembler* masm) {
-  KeyedLoadIC::GenerateMiss(masm);
-}
-
-void Generate_KeyedLoadIC_Megamorphic(MacroAssembler* masm) {
-  KeyedLoadIC::GenerateMegamorphic(masm);
-}
-
-void Generate_StoreIC_Miss(CodeStubAssembler* assembler) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* name = assembler->Parameter(1);
-  Node* value = assembler->Parameter(2);
-  Node* slot = assembler->Parameter(3);
-  Node* vector = assembler->Parameter(4);
-  Node* context = assembler->Parameter(5);
-
-  assembler->TailCallRuntime(Runtime::kStoreIC_Miss, context, receiver, name,
-                             value, slot, vector);
-}
-
-void Generate_StoreIC_Normal(MacroAssembler* masm) {
-  StoreIC::GenerateNormal(masm);
-}
-
-void Generate_StoreIC_Slow(CodeStubAssembler* assembler,
-                           LanguageMode language_mode) {
-  typedef compiler::Node Node;
-
-  Node* receiver = assembler->Parameter(0);
-  Node* name = assembler->Parameter(1);
-  Node* value = assembler->Parameter(2);
-  // Node* slot = assembler->Parameter(3);
-  // Node* vector = assembler->Parameter(4);
-  Node* context = assembler->Parameter(5);
-  Node* lang_mode = assembler->SmiConstant(Smi::FromInt(language_mode));
-
-  // The slow case calls into the runtime to complete the store without causing
-  // an IC miss that would otherwise cause a transition to the generic stub.
-  assembler->TailCallRuntime(Runtime::kSetProperty, context, receiver, name,
-                             value, lang_mode);
-}
-
-void Generate_StoreIC_SlowSloppy(CodeStubAssembler* assembler) {
-  Generate_StoreIC_Slow(assembler, SLOPPY);
-}
-
-void Generate_StoreIC_SlowStrict(CodeStubAssembler* assembler) {
-  Generate_StoreIC_Slow(assembler, STRICT);
-}
-
-void Generate_KeyedStoreIC_Slow(MacroAssembler* masm) {
-  ElementHandlerCompiler::GenerateStoreSlow(masm);
-}
-
-void Generate_StoreIC_Setter_ForDeopt(MacroAssembler* masm) {
-  NamedStoreHandlerCompiler::GenerateStoreViaSetterForDeopt(masm);
-}
-
-void Generate_KeyedStoreIC_Megamorphic(MacroAssembler* masm) {
-  KeyedStoreIC::GenerateMegamorphic(masm, SLOPPY);
-}
-
-void Generate_KeyedStoreIC_Megamorphic_Strict(MacroAssembler* masm) {
-  KeyedStoreIC::GenerateMegamorphic(masm, STRICT);
-}
-
-void Generate_KeyedStoreIC_Miss(MacroAssembler* masm) {
-  KeyedStoreIC::GenerateMiss(masm);
-}
-
-void Generate_Return_DebugBreak(MacroAssembler* masm) {
-  DebugCodegen::GenerateDebugBreakStub(masm,
-                                       DebugCodegen::SAVE_RESULT_REGISTER);
-}
-
-void Generate_Slot_DebugBreak(MacroAssembler* masm) {
-  DebugCodegen::GenerateDebugBreakStub(masm,
-                                       DebugCodegen::IGNORE_RESULT_REGISTER);
-}
-
-void Generate_FrameDropper_LiveEdit(MacroAssembler* masm) {
-  DebugCodegen::GenerateFrameDropperLiveEdit(masm);
-}
-
-}  // namespace
-
-Builtins::Builtins() : initialized_(false) {
-  memset(builtins_, 0, sizeof(builtins_[0]) * builtin_count);
-  memset(names_, 0, sizeof(names_[0]) * builtin_count);
-}
-
-
-Builtins::~Builtins() {
-}
-
-#define DEF_ENUM_C(name, ignore) FUNCTION_ADDR(Builtin_##name),
-Address const Builtins::c_functions_[cfunction_count] = {
-  BUILTIN_LIST_C(DEF_ENUM_C)
-};
-#undef DEF_ENUM_C
-
-
-struct BuiltinDesc {
-  Handle<Code> (*builder)(Isolate*, struct BuiltinDesc const*);
-  byte* generator;
-  byte* c_code;
-  const char* s_name;  // name is only used for generating log information.
-  int name;
-  Code::Flags flags;
-  Builtins::ExitFrameType exit_frame_type;
-  int argc;
-};
-
-#define BUILTIN_FUNCTION_TABLE_INIT { V8_ONCE_INIT, {} }
-
-class BuiltinFunctionTable {
- public:
-  BuiltinDesc* functions() {
-    base::CallOnce(&once_, &Builtins::InitBuiltinFunctionTable);
-    return functions_;
-  }
-
-  base::OnceType once_;
-  BuiltinDesc functions_[Builtins::builtin_count + 1];
-
-  friend class Builtins;
-};
-
-namespace {
-
-BuiltinFunctionTable builtin_function_table = BUILTIN_FUNCTION_TABLE_INIT;
-
-Handle<Code> MacroAssemblerBuilder(Isolate* isolate,
-                                   BuiltinDesc const* builtin_desc) {
-// For now we generate builtin adaptor code into a stack-allocated
-// buffer, before copying it into individual code objects. Be careful
-// with alignment, some platforms don't like unaligned code.
-#ifdef DEBUG
-  // We can generate a lot of debug code on Arm64.
-  const size_t buffer_size = 32 * KB;
-#elif V8_TARGET_ARCH_PPC64
-  // 8 KB is insufficient on PPC64 when FLAG_debug_code is on.
-  const size_t buffer_size = 10 * KB;
-#else
-  const size_t buffer_size = 8 * KB;
-#endif
-  union {
-    int force_alignment;
-    byte buffer[buffer_size];  // NOLINT(runtime/arrays)
-  } u;
-
-  MacroAssembler masm(isolate, u.buffer, sizeof(u.buffer),
-                      CodeObjectRequired::kYes);
-  // Generate the code/adaptor.
-  typedef void (*Generator)(MacroAssembler*, int, Builtins::ExitFrameType);
-  Generator g = FUNCTION_CAST<Generator>(builtin_desc->generator);
-  // We pass all arguments to the generator, but it may not use all of
-  // them.  This works because the first arguments are on top of the
-  // stack.
-  DCHECK(!masm.has_frame());
-  g(&masm, builtin_desc->name, builtin_desc->exit_frame_type);
-  // Move the code into the object heap.
-  CodeDesc desc;
-  masm.GetCode(&desc);
-  Code::Flags flags = builtin_desc->flags;
-  return isolate->factory()->NewCode(desc, flags, masm.CodeObject());
-}
-
-// Builder for builtins implemented in TurboFan with JS linkage.
-Handle<Code> CodeStubAssemblerBuilderJS(Isolate* isolate,
-                                        BuiltinDesc const* builtin_desc) {
-  Zone zone(isolate->allocator());
-  CodeStubAssembler assembler(isolate, &zone, builtin_desc->argc,
-                              builtin_desc->flags, builtin_desc->s_name);
-  // Generate the code/adaptor.
-  typedef void (*Generator)(CodeStubAssembler*);
-  Generator g = FUNCTION_CAST<Generator>(builtin_desc->generator);
-  g(&assembler);
-  return assembler.GenerateCode();
-}
-
-// Builder for builtins implemented in TurboFan with CallStub linkage.
-Handle<Code> CodeStubAssemblerBuilderCS(Isolate* isolate,
-                                        BuiltinDesc const* builtin_desc) {
-  Zone zone(isolate->allocator());
-  // The interface descriptor with given key must be initialized at this point
-  // and this construction just queries the details from the descriptors table.
-  CallInterfaceDescriptor descriptor(
-      isolate, static_cast<CallDescriptors::Key>(builtin_desc->argc));
-  // Ensure descriptor is already initialized.
-  DCHECK_NOT_NULL(descriptor.GetFunctionType());
-  CodeStubAssembler assembler(isolate, &zone, descriptor, builtin_desc->flags,
-                              builtin_desc->s_name);
-  // Generate the code/adaptor.
-  typedef void (*Generator)(CodeStubAssembler*);
-  Generator g = FUNCTION_CAST<Generator>(builtin_desc->generator);
-  g(&assembler);
-  return assembler.GenerateCode();
-}
-
-}  // namespace
-
-// Define array of pointers to generators and C builtin functions.
-// We do this in a sort of roundabout way so that we can do the initialization
-// within the lexical scope of Builtins:: and within a context where
-// Code::Flags names a non-abstract type.
-void Builtins::InitBuiltinFunctionTable() {
-  BuiltinDesc* functions = builtin_function_table.functions_;
-  functions[builtin_count].builder = nullptr;
-  functions[builtin_count].generator = nullptr;
-  functions[builtin_count].c_code = nullptr;
-  functions[builtin_count].s_name = nullptr;
-  functions[builtin_count].name = builtin_count;
-  functions[builtin_count].flags = static_cast<Code::Flags>(0);
-  functions[builtin_count].exit_frame_type = EXIT;
-  functions[builtin_count].argc = 0;
-
-#define DEF_FUNCTION_PTR_C(aname, aexit_frame_type)       \
-  functions->builder = &MacroAssemblerBuilder;            \
-  functions->generator = FUNCTION_ADDR(Generate_Adaptor); \
-  functions->c_code = FUNCTION_ADDR(Builtin_##aname);     \
-  functions->s_name = #aname;                             \
-  functions->name = c_##aname;                            \
-  functions->flags = Code::ComputeFlags(Code::BUILTIN);   \
-  functions->exit_frame_type = aexit_frame_type;          \
-  functions->argc = 0;                                    \
-  ++functions;
-
-#define DEF_FUNCTION_PTR_A(aname, kind, extra)              \
-  functions->builder = &MacroAssemblerBuilder;              \
-  functions->generator = FUNCTION_ADDR(Generate_##aname);   \
-  functions->c_code = NULL;                                 \
-  functions->s_name = #aname;                               \
-  functions->name = k##aname;                               \
-  functions->flags = Code::ComputeFlags(Code::kind, extra); \
-  functions->exit_frame_type = EXIT;                        \
-  functions->argc = 0;                                      \
-  ++functions;
-
-#define DEF_FUNCTION_PTR_T(aname, aargc)                  \
-  functions->builder = &CodeStubAssemblerBuilderJS;       \
-  functions->generator = FUNCTION_ADDR(Generate_##aname); \
-  functions->c_code = NULL;                               \
-  functions->s_name = #aname;                             \
-  functions->name = k##aname;                             \
-  functions->flags = Code::ComputeFlags(Code::BUILTIN);   \
-  functions->exit_frame_type = EXIT;                      \
-  functions->argc = aargc;                                \
-  ++functions;
-
-#define DEF_FUNCTION_PTR_S(aname, kind, extra, interface_descriptor) \
-  functions->builder = &CodeStubAssemblerBuilderCS;                  \
-  functions->generator = FUNCTION_ADDR(Generate_##aname);            \
-  functions->c_code = NULL;                                          \
-  functions->s_name = #aname;                                        \
-  functions->name = k##aname;                                        \
-  functions->flags = Code::ComputeFlags(Code::kind, extra);          \
-  functions->exit_frame_type = EXIT;                                 \
-  functions->argc = CallDescriptors::interface_descriptor;           \
-  ++functions;
-
-#define DEF_FUNCTION_PTR_H(aname, kind)                     \
-  functions->builder = &MacroAssemblerBuilder;              \
-  functions->generator = FUNCTION_ADDR(Generate_##aname);   \
-  functions->c_code = NULL;                                 \
-  functions->s_name = #aname;                               \
-  functions->name = k##aname;                               \
-  functions->flags = Code::ComputeHandlerFlags(Code::kind); \
-  functions->exit_frame_type = EXIT;                        \
-  functions->argc = 0;                                      \
-  ++functions;
-
-  BUILTIN_LIST_C(DEF_FUNCTION_PTR_C)
-  BUILTIN_LIST_A(DEF_FUNCTION_PTR_A)
-  BUILTIN_LIST_T(DEF_FUNCTION_PTR_T)
-  BUILTIN_LIST_S(DEF_FUNCTION_PTR_S)
-  BUILTIN_LIST_H(DEF_FUNCTION_PTR_H)
-  BUILTIN_LIST_DEBUG_A(DEF_FUNCTION_PTR_A)
-
-#undef DEF_FUNCTION_PTR_C
-#undef DEF_FUNCTION_PTR_A
-#undef DEF_FUNCTION_PTR_T
-#undef DEF_FUNCTION_PTR_S
-#undef DEF_FUNCTION_PTR_H
-}
-
-
-void Builtins::SetUp(Isolate* isolate, bool create_heap_objects) {
-  DCHECK(!initialized_);
-
-  // Create a scope for the handles in the builtins.
-  HandleScope scope(isolate);
-
-#define INITIALIZE_CALL_DESCRIPTOR(name, kind, extra, interface_descriptor) \
-  { interface_descriptor##Descriptor descriptor(isolate); }
-  BUILTIN_LIST_S(INITIALIZE_CALL_DESCRIPTOR)
-#undef INITIALIZE_CALL_DESCRIPTOR
-
-  const BuiltinDesc* functions = builtin_function_table.functions();
-
-  // Traverse the list of builtins and generate an adaptor in a
-  // separate code object for each one.
-  for (int i = 0; i < builtin_count; i++) {
-    if (create_heap_objects) {
-      Handle<Code> code = (*functions[i].builder)(isolate, functions + i);
-      // Log the event and add the code to the builtins array.
-      PROFILE(isolate,
-              CodeCreateEvent(CodeEventListener::BUILTIN_TAG,
-                              AbstractCode::cast(*code), functions[i].s_name));
-      builtins_[i] = *code;
-      code->set_builtin_index(i);
-#ifdef ENABLE_DISASSEMBLER
-      if (FLAG_print_builtin_code) {
-        CodeTracer::Scope trace_scope(isolate->GetCodeTracer());
-        OFStream os(trace_scope.file());
-        os << "Builtin: " << functions[i].s_name << "\n";
-        code->Disassemble(functions[i].s_name, os);
-        os << "\n";
-      }
-#endif
-    } else {
-      // Deserializing. The values will be filled in during IterateBuiltins.
-      builtins_[i] = NULL;
-    }
-    names_[i] = functions[i].s_name;
-  }
-
-  // Mark as initialized.
-  initialized_ = true;
-}
-
-
-void Builtins::TearDown() {
-  initialized_ = false;
-}
-
-
-void Builtins::IterateBuiltins(ObjectVisitor* v) {
-  v->VisitPointers(&builtins_[0], &builtins_[0] + builtin_count);
-}
-
-
-const char* Builtins::Lookup(byte* pc) {
-  // may be called during initialization (disassembler!)
-  if (initialized_) {
-    for (int i = 0; i < builtin_count; i++) {
-      Code* entry = Code::cast(builtins_[i]);
-      if (entry->contains(pc)) {
-        return names_[i];
-      }
-    }
-  }
-  return NULL;
-}
-
-
-void Builtins::Generate_InterruptCheck(MacroAssembler* masm) {
-  masm->TailCallRuntime(Runtime::kInterrupt);
-}
-
-
-void Builtins::Generate_StackCheck(MacroAssembler* masm) {
-  masm->TailCallRuntime(Runtime::kStackGuard);
-}
-
-namespace {
-
-void ValidateSharedTypedArray(CodeStubAssembler* a, compiler::Node* tagged,
-                              compiler::Node* context,
-                              compiler::Node** out_instance_type,
-                              compiler::Node** out_backing_store) {
-  using namespace compiler;
-  CodeStubAssembler::Label is_smi(a), not_smi(a), is_typed_array(a),
-      not_typed_array(a), is_shared(a), not_shared(a), is_float_or_clamped(a),
-      not_float_or_clamped(a), invalid(a);
-
-  // Fail if it is not a heap object.
-  a->Branch(a->WordIsSmi(tagged), &is_smi, &not_smi);
-  a->Bind(&is_smi);
-  a->Goto(&invalid);
-
-  // Fail if the array's instance type is not JSTypedArray.
-  a->Bind(&not_smi);
-  a->Branch(a->WordEqual(a->LoadInstanceType(tagged),
-                         a->Int32Constant(JS_TYPED_ARRAY_TYPE)),
-            &is_typed_array, &not_typed_array);
-  a->Bind(&not_typed_array);
-  a->Goto(&invalid);
-
-  // Fail if the array's JSArrayBuffer is not shared.
-  a->Bind(&is_typed_array);
-  Node* array_buffer = a->LoadObjectField(tagged, JSTypedArray::kBufferOffset);
-  Node* is_buffer_shared = a->BitFieldDecode<JSArrayBuffer::IsShared>(
-      a->LoadObjectField(array_buffer, JSArrayBuffer::kBitFieldSlot));
-  a->Branch(is_buffer_shared, &is_shared, &not_shared);
-  a->Bind(&not_shared);
-  a->Goto(&invalid);
-
-  // Fail if the array's element type is float32, float64 or clamped.
-  a->Bind(&is_shared);
-  Node* elements_instance_type = a->LoadInstanceType(
-      a->LoadObjectField(tagged, JSObject::kElementsOffset));
-  STATIC_ASSERT(FIXED_INT8_ARRAY_TYPE < FIXED_FLOAT32_ARRAY_TYPE);
-  STATIC_ASSERT(FIXED_INT16_ARRAY_TYPE < FIXED_FLOAT32_ARRAY_TYPE);
-  STATIC_ASSERT(FIXED_INT32_ARRAY_TYPE < FIXED_FLOAT32_ARRAY_TYPE);
-  STATIC_ASSERT(FIXED_UINT8_ARRAY_TYPE < FIXED_FLOAT32_ARRAY_TYPE);
-  STATIC_ASSERT(FIXED_UINT16_ARRAY_TYPE < FIXED_FLOAT32_ARRAY_TYPE);
-  STATIC_ASSERT(FIXED_UINT32_ARRAY_TYPE < FIXED_FLOAT32_ARRAY_TYPE);
-  a->Branch(a->Int32LessThan(elements_instance_type,
-                             a->Int32Constant(FIXED_FLOAT32_ARRAY_TYPE)),
-            &not_float_or_clamped, &is_float_or_clamped);
-  a->Bind(&is_float_or_clamped);
-  a->Goto(&invalid);
-
-  a->Bind(&invalid);
-  a->CallRuntime(Runtime::kThrowNotIntegerSharedTypedArrayError, context,
-                 tagged);
-  a->Return(a->UndefinedConstant());
-
-  a->Bind(&not_float_or_clamped);
-  *out_instance_type = elements_instance_type;
-
-  Node* backing_store =
-      a->LoadObjectField(array_buffer, JSArrayBuffer::kBackingStoreOffset);
-  Node* byte_offset = a->ChangeUint32ToWord(a->TruncateTaggedToWord32(
-      context,
-      a->LoadObjectField(tagged, JSArrayBufferView::kByteOffsetOffset)));
-  *out_backing_store = a->IntPtrAdd(backing_store, byte_offset);
-}
-
-// https://tc39.github.io/ecmascript_sharedmem/shmem.html#Atomics.ValidateAtomicAccess
-compiler::Node* ConvertTaggedAtomicIndexToWord32(CodeStubAssembler* a,
-                                                 compiler::Node* tagged,
-                                                 compiler::Node* context) {
-  using namespace compiler;
-  CodeStubAssembler::Variable var_result(a, MachineRepresentation::kWord32);
-
-  Callable to_number = CodeFactory::ToNumber(a->isolate());
-  Node* number_index = a->CallStub(to_number, context, tagged);
-  CodeStubAssembler::Label done(a, &var_result);
-
-  CodeStubAssembler::Label if_numberissmi(a), if_numberisnotsmi(a);
-  a->Branch(a->WordIsSmi(number_index), &if_numberissmi, &if_numberisnotsmi);
-
-  a->Bind(&if_numberissmi);
-  {
-    var_result.Bind(a->SmiToWord32(number_index));
-    a->Goto(&done);
-  }
-
-  a->Bind(&if_numberisnotsmi);
-  {
-    Node* number_index_value = a->LoadHeapNumberValue(number_index);
-    Node* access_index = a->TruncateFloat64ToWord32(number_index_value);
-    Node* test_index = a->ChangeInt32ToFloat64(access_index);
-
-    CodeStubAssembler::Label if_indexesareequal(a), if_indexesarenotequal(a);
-    a->Branch(a->Float64Equal(number_index_value, test_index),
-              &if_indexesareequal, &if_indexesarenotequal);
-
-    a->Bind(&if_indexesareequal);
-    {
-      var_result.Bind(access_index);
-      a->Goto(&done);
-    }
-
-    a->Bind(&if_indexesarenotequal);
-    a->Return(
-        a->CallRuntime(Runtime::kThrowInvalidAtomicAccessIndexError, context));
-  }
-
-  a->Bind(&done);
-  return var_result.value();
-}
-
-void ValidateAtomicIndex(CodeStubAssembler* a, compiler::Node* index_word,
-                         compiler::Node* array_length_word,
-                         compiler::Node* context) {
-  using namespace compiler;
-  // Check if the index is in bounds. If not, throw RangeError.
-  CodeStubAssembler::Label if_inbounds(a), if_notinbounds(a);
-  a->Branch(
-      a->WordOr(a->Int32LessThan(index_word, a->Int32Constant(0)),
-                a->Int32GreaterThanOrEqual(index_word, array_length_word)),
-      &if_notinbounds, &if_inbounds);
-  a->Bind(&if_notinbounds);
-  a->Return(
-      a->CallRuntime(Runtime::kThrowInvalidAtomicAccessIndexError, context));
-  a->Bind(&if_inbounds);
-}
-
-}  // anonymous namespace
-
-void Builtins::Generate_AtomicsLoad(CodeStubAssembler* a) {
-  using namespace compiler;
-  Node* array = a->Parameter(1);
-  Node* index = a->Parameter(2);
-  Node* context = a->Parameter(3 + 2);
-
-  Node* instance_type;
-  Node* backing_store;
-  ValidateSharedTypedArray(a, array, context, &instance_type, &backing_store);
-
-  Node* index_word32 = ConvertTaggedAtomicIndexToWord32(a, index, context);
-  Node* array_length_word32 = a->TruncateTaggedToWord32(
-      context, a->LoadObjectField(array, JSTypedArray::kLengthOffset));
-  ValidateAtomicIndex(a, index_word32, array_length_word32, context);
-  Node* index_word = a->ChangeUint32ToWord(index_word32);
-
-  CodeStubAssembler::Label i8(a), u8(a), i16(a), u16(a), i32(a), u32(a),
-      other(a);
-  int32_t case_values[] = {
-      FIXED_INT8_ARRAY_TYPE,   FIXED_UINT8_ARRAY_TYPE, FIXED_INT16_ARRAY_TYPE,
-      FIXED_UINT16_ARRAY_TYPE, FIXED_INT32_ARRAY_TYPE, FIXED_UINT32_ARRAY_TYPE,
-  };
-  CodeStubAssembler::Label* case_labels[] = {
-      &i8, &u8, &i16, &u16, &i32, &u32,
-  };
-  a->Switch(instance_type, &other, case_values, case_labels,
-            arraysize(case_labels));
-
-  a->Bind(&i8);
-  a->Return(
-      a->SmiTag(a->AtomicLoad(MachineType::Int8(), backing_store, index_word)));
-
-  a->Bind(&u8);
-  a->Return(a->SmiTag(
-      a->AtomicLoad(MachineType::Uint8(), backing_store, index_word)));
-
-  a->Bind(&i16);
-  a->Return(a->SmiTag(a->AtomicLoad(MachineType::Int16(), backing_store,
-                                    a->WordShl(index_word, 1))));
-
-  a->Bind(&u16);
-  a->Return(a->SmiTag(a->AtomicLoad(MachineType::Uint16(), backing_store,
-                                    a->WordShl(index_word, 1))));
-
-  a->Bind(&i32);
-  a->Return(a->ChangeInt32ToTagged(a->AtomicLoad(
-      MachineType::Int32(), backing_store, a->WordShl(index_word, 2))));
-
-  a->Bind(&u32);
-  a->Return(a->ChangeUint32ToTagged(a->AtomicLoad(
-      MachineType::Uint32(), backing_store, a->WordShl(index_word, 2))));
-
-  // This shouldn't happen, we've already validated the type.
-  a->Bind(&other);
-  a->Return(a->Int32Constant(0));
-}
-
-void Builtins::Generate_AtomicsStore(CodeStubAssembler* a) {
-  using namespace compiler;
-  Node* array = a->Parameter(1);
-  Node* index = a->Parameter(2);
-  Node* value = a->Parameter(3);
-  Node* context = a->Parameter(4 + 2);
-
-  Node* instance_type;
-  Node* backing_store;
-  ValidateSharedTypedArray(a, array, context, &instance_type, &backing_store);
-
-  Node* index_word32 = ConvertTaggedAtomicIndexToWord32(a, index, context);
-  Node* array_length_word32 = a->TruncateTaggedToWord32(
-      context, a->LoadObjectField(array, JSTypedArray::kLengthOffset));
-  ValidateAtomicIndex(a, index_word32, array_length_word32, context);
-  Node* index_word = a->ChangeUint32ToWord(index_word32);
-
-  Callable to_integer = CodeFactory::ToInteger(a->isolate());
-  Node* value_integer = a->CallStub(to_integer, context, value);
-  Node* value_word32 = a->TruncateTaggedToWord32(context, value_integer);
-
-  CodeStubAssembler::Label u8(a), u16(a), u32(a), other(a);
-  int32_t case_values[] = {
-      FIXED_INT8_ARRAY_TYPE,   FIXED_UINT8_ARRAY_TYPE, FIXED_INT16_ARRAY_TYPE,
-      FIXED_UINT16_ARRAY_TYPE, FIXED_INT32_ARRAY_TYPE, FIXED_UINT32_ARRAY_TYPE,
-  };
-  CodeStubAssembler::Label* case_labels[] = {
-      &u8, &u8, &u16, &u16, &u32, &u32,
-  };
-  a->Switch(instance_type, &other, case_values, case_labels,
-            arraysize(case_labels));
-
-  a->Bind(&u8);
-  a->AtomicStore(MachineRepresentation::kWord8, backing_store, index_word,
-                 value_word32);
-  a->Return(value_integer);
-
-  a->Bind(&u16);
-  a->SmiTag(a->AtomicStore(MachineRepresentation::kWord16, backing_store,
-                           a->WordShl(index_word, 1), value_word32));
-  a->Return(value_integer);
-
-  a->Bind(&u32);
-  a->AtomicStore(MachineRepresentation::kWord32, backing_store,
-                 a->WordShl(index_word, 2), value_word32);
-  a->Return(value_integer);
-
-  // This shouldn't happen, we've already validated the type.
-  a->Bind(&other);
-  a->Return(a->Int32Constant(0));
-}
-
-#define DEFINE_BUILTIN_ACCESSOR_C(name, ignore)                               \
-  Handle<Code> Builtins::name() {                                             \
-    Code** code_address = reinterpret_cast<Code**>(builtin_address(k##name)); \
-    return Handle<Code>(code_address);                                        \
-  }
-#define DEFINE_BUILTIN_ACCESSOR_A(name, kind, extra)                          \
-  Handle<Code> Builtins::name() {                                             \
-    Code** code_address = reinterpret_cast<Code**>(builtin_address(k##name)); \
-    return Handle<Code>(code_address);                                        \
-  }
-#define DEFINE_BUILTIN_ACCESSOR_T(name, argc)                                 \
-  Handle<Code> Builtins::name() {                                             \
-    Code** code_address = reinterpret_cast<Code**>(builtin_address(k##name)); \
-    return Handle<Code>(code_address);                                        \
-  }
-#define DEFINE_BUILTIN_ACCESSOR_S(name, kind, extra, interface_descriptor)    \
-  Handle<Code> Builtins::name() {                                             \
-    Code** code_address = reinterpret_cast<Code**>(builtin_address(k##name)); \
-    return Handle<Code>(code_address);                                        \
-  }
-#define DEFINE_BUILTIN_ACCESSOR_H(name, kind)               \
-Handle<Code> Builtins::name() {                             \
-  Code** code_address =                                     \
-      reinterpret_cast<Code**>(builtin_address(k##name));   \
-  return Handle<Code>(code_address);                        \
-}
-BUILTIN_LIST_C(DEFINE_BUILTIN_ACCESSOR_C)
-BUILTIN_LIST_A(DEFINE_BUILTIN_ACCESSOR_A)
-BUILTIN_LIST_T(DEFINE_BUILTIN_ACCESSOR_T)
-BUILTIN_LIST_S(DEFINE_BUILTIN_ACCESSOR_S)
-BUILTIN_LIST_H(DEFINE_BUILTIN_ACCESSOR_H)
-BUILTIN_LIST_DEBUG_A(DEFINE_BUILTIN_ACCESSOR_A)
-#undef DEFINE_BUILTIN_ACCESSOR_C
-#undef DEFINE_BUILTIN_ACCESSOR_A
-#undef DEFINE_BUILTIN_ACCESSOR_T
-#undef DEFINE_BUILTIN_ACCESSOR_S
-#undef DEFINE_BUILTIN_ACCESSOR_H
-
-}  // namespace internal
-}  // namespace v8