js-create-lowering.cc 76.5 KB
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// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "src/compiler/js-create-lowering.h"

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#include "src/allocation-site-scopes.h"
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#include "src/code-factory.h"
#include "src/compilation-dependencies.h"
#include "src/compiler/access-builder.h"
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#include "src/compiler/allocation-builder.h"
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#include "src/compiler/common-operator.h"
#include "src/compiler/js-graph.h"
#include "src/compiler/js-operator.h"
#include "src/compiler/linkage.h"
#include "src/compiler/node-properties.h"
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#include "src/compiler/node.h"
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#include "src/compiler/operator-properties.h"
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#include "src/compiler/simplified-operator.h"
#include "src/compiler/state-values-utils.h"
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#include "src/objects-inl.h"
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namespace v8 {
namespace internal {
namespace compiler {

namespace {

// Retrieves the frame state holding actual argument values.
Node* GetArgumentsFrameState(Node* frame_state) {
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  Node* const outer_state = NodeProperties::GetFrameStateInput(frame_state);
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  FrameStateInfo outer_state_info = OpParameter<FrameStateInfo>(outer_state);
  return outer_state_info.type() == FrameStateType::kArgumentsAdaptor
             ? outer_state
             : frame_state;
}

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// Checks whether allocation using the given target and new.target can be
// inlined.
bool IsAllocationInlineable(Handle<JSFunction> target,
                            Handle<JSFunction> new_target) {
  return new_target->has_initial_map() &&
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         !new_target->initial_map()->is_dictionary_map() &&
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         new_target->initial_map()->constructor_or_backpointer() == *target;
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}

// When initializing arrays, we'll unfold the loop if the number of
// elements is known to be of this type.
const int kElementLoopUnrollLimit = 16;

// Limits up to which context allocations are inlined.
const int kFunctionContextAllocationLimit = 16;
const int kBlockContextAllocationLimit = 16;

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// Determines whether the given array or object literal boilerplate satisfies
// all limits to be considered for fast deep-copying and computes the total
// size of all objects that are part of the graph.
bool IsFastLiteral(Handle<JSObject> boilerplate, int max_depth,
                   int* max_properties) {
  DCHECK_GE(max_depth, 0);
  DCHECK_GE(*max_properties, 0);

  // Make sure the boilerplate map is not deprecated.
  if (!JSObject::TryMigrateInstance(boilerplate)) return false;

  // Check for too deep nesting.
  if (max_depth == 0) return false;

  // Check the elements.
  Isolate* const isolate = boilerplate->GetIsolate();
  Handle<FixedArrayBase> elements(boilerplate->elements(), isolate);
  if (elements->length() > 0 &&
      elements->map() != isolate->heap()->fixed_cow_array_map()) {
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    if (boilerplate->HasSmiOrObjectElements()) {
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      Handle<FixedArray> fast_elements = Handle<FixedArray>::cast(elements);
      int length = elements->length();
      for (int i = 0; i < length; i++) {
        if ((*max_properties)-- == 0) return false;
        Handle<Object> value(fast_elements->get(i), isolate);
        if (value->IsJSObject()) {
          Handle<JSObject> value_object = Handle<JSObject>::cast(value);
          if (!IsFastLiteral(value_object, max_depth - 1, max_properties)) {
            return false;
          }
        }
      }
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    } else if (boilerplate->HasDoubleElements()) {
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      if (elements->Size() > kMaxRegularHeapObjectSize) return false;
    } else {
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      return false;
    }
  }

  // TODO(turbofan): Do we want to support out-of-object properties?
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  if (!(boilerplate->HasFastProperties() &&
        boilerplate->property_array()->length() == 0)) {
    return false;
  }
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  // Check the in-object properties.
  Handle<DescriptorArray> descriptors(
      boilerplate->map()->instance_descriptors(), isolate);
  int limit = boilerplate->map()->NumberOfOwnDescriptors();
  for (int i = 0; i < limit; i++) {
    PropertyDetails details = descriptors->GetDetails(i);
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    if (details.location() != kField) continue;
    DCHECK_EQ(kData, details.kind());
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    if ((*max_properties)-- == 0) return false;
    FieldIndex field_index = FieldIndex::ForDescriptor(boilerplate->map(), i);
    if (boilerplate->IsUnboxedDoubleField(field_index)) continue;
    Handle<Object> value(boilerplate->RawFastPropertyAt(field_index), isolate);
    if (value->IsJSObject()) {
      Handle<JSObject> value_object = Handle<JSObject>::cast(value);
      if (!IsFastLiteral(value_object, max_depth - 1, max_properties)) {
        return false;
      }
    }
  }
  return true;
}

// Maximum depth and total number of elements and properties for literal
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// graphs to be considered for fast deep-copying. The limit is chosen to
// match the maximum number of inobject properties, to ensure that the
// performance of using object literals is not worse than using constructor
// functions, see crbug.com/v8/6211 for details.
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const int kMaxFastLiteralDepth = 3;
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const int kMaxFastLiteralProperties = JSObject::kMaxInObjectProperties;
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}  // namespace

Reduction JSCreateLowering::Reduce(Node* node) {
  switch (node->opcode()) {
    case IrOpcode::kJSCreate:
      return ReduceJSCreate(node);
    case IrOpcode::kJSCreateArguments:
      return ReduceJSCreateArguments(node);
    case IrOpcode::kJSCreateArray:
      return ReduceJSCreateArray(node);
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    case IrOpcode::kJSCreateBoundFunction:
      return ReduceJSCreateBoundFunction(node);
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    case IrOpcode::kJSCreateClosure:
      return ReduceJSCreateClosure(node);
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    case IrOpcode::kJSCreateIterResultObject:
      return ReduceJSCreateIterResultObject(node);
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    case IrOpcode::kJSCreateKeyValueArray:
      return ReduceJSCreateKeyValueArray(node);
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    case IrOpcode::kJSCreateLiteralArray:
    case IrOpcode::kJSCreateLiteralObject:
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      return ReduceJSCreateLiteralArrayOrObject(node);
    case IrOpcode::kJSCreateLiteralRegExp:
      return ReduceJSCreateLiteralRegExp(node);
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    case IrOpcode::kJSCreateEmptyLiteralArray:
      return ReduceJSCreateEmptyLiteralArray(node);
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    case IrOpcode::kJSCreateEmptyLiteralObject:
      return ReduceJSCreateEmptyLiteralObject(node);
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    case IrOpcode::kJSCreateFunctionContext:
      return ReduceJSCreateFunctionContext(node);
    case IrOpcode::kJSCreateWithContext:
      return ReduceJSCreateWithContext(node);
    case IrOpcode::kJSCreateCatchContext:
      return ReduceJSCreateCatchContext(node);
    case IrOpcode::kJSCreateBlockContext:
      return ReduceJSCreateBlockContext(node);
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    case IrOpcode::kJSCreateGeneratorObject:
      return ReduceJSCreateGeneratorObject(node);
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    default:
      break;
  }
  return NoChange();
}

Reduction JSCreateLowering::ReduceJSCreate(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreate, node->opcode());
  Node* const target = NodeProperties::GetValueInput(node, 0);
  Type* const target_type = NodeProperties::GetType(target);
  Node* const new_target = NodeProperties::GetValueInput(node, 1);
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  Type* const new_target_type = NodeProperties::GetType(new_target);
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  Node* const effect = NodeProperties::GetEffectInput(node);
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  Node* const control = NodeProperties::GetControlInput(node);
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  // Extract constructor and original constructor function.
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  if (target_type->IsHeapConstant() && new_target_type->IsHeapConstant() &&
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      target_type->AsHeapConstant()->Value()->IsJSFunction() &&
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      new_target_type->AsHeapConstant()->Value()->IsJSFunction()) {
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    Handle<JSFunction> constructor =
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        Handle<JSFunction>::cast(target_type->AsHeapConstant()->Value());
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    if (!constructor->IsConstructor()) return NoChange();
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    Handle<JSFunction> original_constructor =
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        Handle<JSFunction>::cast(new_target_type->AsHeapConstant()->Value());
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    if (!original_constructor->IsConstructor()) return NoChange();
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    // Check if we can inline the allocation.
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    if (IsAllocationInlineable(constructor, original_constructor)) {
      // Force completion of inobject slack tracking before
      // generating code to finalize the instance size.
      original_constructor->CompleteInobjectSlackTrackingIfActive();
      Handle<Map> initial_map(original_constructor->initial_map(), isolate());
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      int const instance_size = initial_map->instance_size();

      // Add a dependency on the {initial_map} to make sure that this code is
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      // deoptimized whenever the {initial_map} changes.
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      dependencies()->AssumeInitialMapCantChange(initial_map);

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      // Emit code to allocate the JSObject instance for the
      // {original_constructor}.
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      AllocationBuilder a(jsgraph(), effect, control);
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      a.Allocate(instance_size);
      a.Store(AccessBuilder::ForMap(), initial_map);
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      a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(),
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              jsgraph()->EmptyFixedArrayConstant());
      a.Store(AccessBuilder::ForJSObjectElements(),
              jsgraph()->EmptyFixedArrayConstant());
      for (int i = 0; i < initial_map->GetInObjectProperties(); ++i) {
        a.Store(AccessBuilder::ForJSObjectInObjectProperty(initial_map, i),
                jsgraph()->UndefinedConstant());
      }
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      RelaxControls(node);
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      a.FinishAndChange(node);
      return Changed(node);
    }
  }
  return NoChange();
}

Reduction JSCreateLowering::ReduceJSCreateArguments(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateArguments, node->opcode());
  CreateArgumentsType type = CreateArgumentsTypeOf(node->op());
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  Node* const frame_state = NodeProperties::GetFrameStateInput(node);
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  Node* const outer_state = frame_state->InputAt(kFrameStateOuterStateInput);
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  Node* const control = graph()->start();
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  FrameStateInfo state_info = OpParameter<FrameStateInfo>(frame_state);
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  Handle<SharedFunctionInfo> shared =
      state_info.shared_info().ToHandleChecked();
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  // Use the ArgumentsAccessStub for materializing both mapped and unmapped
  // arguments object, but only for non-inlined (i.e. outermost) frames.
  if (outer_state->opcode() != IrOpcode::kFrameState) {
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    switch (type) {
      case CreateArgumentsType::kMappedArguments: {
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        // TODO(mstarzinger): Duplicate parameters are not handled yet.
        if (shared->has_duplicate_parameters()) return NoChange();
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        Node* const callee = NodeProperties::GetValueInput(node, 0);
        Node* const context = NodeProperties::GetContextInput(node);
        Node* effect = NodeProperties::GetEffectInput(node);
        Node* const arguments_frame =
            graph()->NewNode(simplified()->ArgumentsFrame());
        Node* const arguments_length = graph()->NewNode(
            simplified()->ArgumentsLength(
                shared->internal_formal_parameter_count(), false),
            arguments_frame);
        // Allocate the elements backing store.
        bool has_aliased_arguments = false;
        Node* const elements = effect = AllocateAliasedArguments(
            effect, control, context, arguments_frame, arguments_length, shared,
            &has_aliased_arguments);
        // Load the arguments object map.
        Node* const arguments_map = jsgraph()->HeapConstant(
            handle(has_aliased_arguments
                       ? native_context()->fast_aliased_arguments_map()
                       : native_context()->sloppy_arguments_map(),
                   isolate()));
        // Actually allocate and initialize the arguments object.
        AllocationBuilder a(jsgraph(), effect, control);
        Node* properties = jsgraph()->EmptyFixedArrayConstant();
        STATIC_ASSERT(JSSloppyArgumentsObject::kSize == 5 * kPointerSize);
        a.Allocate(JSSloppyArgumentsObject::kSize);
        a.Store(AccessBuilder::ForMap(), arguments_map);
        a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
        a.Store(AccessBuilder::ForJSObjectElements(), elements);
        a.Store(AccessBuilder::ForArgumentsLength(), arguments_length);
        a.Store(AccessBuilder::ForArgumentsCallee(), callee);
        RelaxControls(node);
        a.FinishAndChange(node);
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        return Changed(node);
      }
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      case CreateArgumentsType::kUnmappedArguments: {
        Node* effect = NodeProperties::GetEffectInput(node);
        Node* const arguments_frame =
            graph()->NewNode(simplified()->ArgumentsFrame());
        Node* const arguments_length = graph()->NewNode(
            simplified()->ArgumentsLength(
                shared->internal_formal_parameter_count(), false),
            arguments_frame);
        // Allocate the elements backing store.
        Node* const elements = effect =
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            graph()->NewNode(simplified()->NewArgumentsElements(0),
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                             arguments_frame, arguments_length, effect);
        // Load the arguments object map.
        Node* const arguments_map = jsgraph()->HeapConstant(
            handle(native_context()->strict_arguments_map(), isolate()));
        // Actually allocate and initialize the arguments object.
        AllocationBuilder a(jsgraph(), effect, control);
        Node* properties = jsgraph()->EmptyFixedArrayConstant();
        STATIC_ASSERT(JSStrictArgumentsObject::kSize == 4 * kPointerSize);
        a.Allocate(JSStrictArgumentsObject::kSize);
        a.Store(AccessBuilder::ForMap(), arguments_map);
        a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
        a.Store(AccessBuilder::ForJSObjectElements(), elements);
        a.Store(AccessBuilder::ForArgumentsLength(), arguments_length);
        RelaxControls(node);
        a.FinishAndChange(node);
        return Changed(node);
      }
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      case CreateArgumentsType::kRestParameter: {
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        Node* effect = NodeProperties::GetEffectInput(node);
        Node* const arguments_frame =
            graph()->NewNode(simplified()->ArgumentsFrame());
        Node* const rest_length = graph()->NewNode(
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            simplified()->ArgumentsLength(
                shared->internal_formal_parameter_count(), true),
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            arguments_frame);
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        // Allocate the elements backing store. Since NewArgumentsElements
        // copies from the end of the arguments adapter frame, this is a suffix
        // of the actual arguments.
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        Node* const elements = effect =
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            graph()->NewNode(simplified()->NewArgumentsElements(0),
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                             arguments_frame, rest_length, effect);
        // Load the JSArray object map.
        Node* const jsarray_map = jsgraph()->HeapConstant(handle(
            native_context()->js_array_fast_elements_map_index(), isolate()));
        // Actually allocate and initialize the jsarray.
        AllocationBuilder a(jsgraph(), effect, control);
        Node* properties = jsgraph()->EmptyFixedArrayConstant();
        STATIC_ASSERT(JSArray::kSize == 4 * kPointerSize);
        a.Allocate(JSArray::kSize);
        a.Store(AccessBuilder::ForMap(), jsarray_map);
        a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
        a.Store(AccessBuilder::ForJSObjectElements(), elements);
        a.Store(AccessBuilder::ForJSArrayLength(PACKED_ELEMENTS), rest_length);
        RelaxControls(node);
        a.FinishAndChange(node);
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        return Changed(node);
      }
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    }
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    UNREACHABLE();
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  } else if (outer_state->opcode() == IrOpcode::kFrameState) {
    // Use inline allocation for all mapped arguments objects within inlined
    // (i.e. non-outermost) frames, independent of the object size.
    if (type == CreateArgumentsType::kMappedArguments) {
      Node* const callee = NodeProperties::GetValueInput(node, 0);
      Node* const context = NodeProperties::GetContextInput(node);
      Node* effect = NodeProperties::GetEffectInput(node);
      // TODO(mstarzinger): Duplicate parameters are not handled yet.
      if (shared->has_duplicate_parameters()) return NoChange();
      // Choose the correct frame state and frame state info depending on
      // whether there conceptually is an arguments adaptor frame in the call
      // chain.
      Node* const args_state = GetArgumentsFrameState(frame_state);
      FrameStateInfo args_state_info = OpParameter<FrameStateInfo>(args_state);
      // Prepare element backing store to be used by arguments object.
      bool has_aliased_arguments = false;
      Node* const elements = AllocateAliasedArguments(
          effect, control, args_state, context, shared, &has_aliased_arguments);
      effect = elements->op()->EffectOutputCount() > 0 ? elements : effect;
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      // Load the arguments object map.
      Node* const arguments_map = jsgraph()->HeapConstant(handle(
          has_aliased_arguments ? native_context()->fast_aliased_arguments_map()
                                : native_context()->sloppy_arguments_map(),
          isolate()));
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      // Actually allocate and initialize the arguments object.
      AllocationBuilder a(jsgraph(), effect, control);
      Node* properties = jsgraph()->EmptyFixedArrayConstant();
      int length = args_state_info.parameter_count() - 1;  // Minus receiver.
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      STATIC_ASSERT(JSSloppyArgumentsObject::kSize == 5 * kPointerSize);
      a.Allocate(JSSloppyArgumentsObject::kSize);
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      a.Store(AccessBuilder::ForMap(), arguments_map);
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      a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
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      a.Store(AccessBuilder::ForJSObjectElements(), elements);
      a.Store(AccessBuilder::ForArgumentsLength(), jsgraph()->Constant(length));
      a.Store(AccessBuilder::ForArgumentsCallee(), callee);
      RelaxControls(node);
      a.FinishAndChange(node);
      return Changed(node);
    } else if (type == CreateArgumentsType::kUnmappedArguments) {
      // Use inline allocation for all unmapped arguments objects within inlined
      // (i.e. non-outermost) frames, independent of the object size.
      Node* effect = NodeProperties::GetEffectInput(node);
      // Choose the correct frame state and frame state info depending on
      // whether there conceptually is an arguments adaptor frame in the call
      // chain.
      Node* const args_state = GetArgumentsFrameState(frame_state);
      FrameStateInfo args_state_info = OpParameter<FrameStateInfo>(args_state);
      // Prepare element backing store to be used by arguments object.
      Node* const elements = AllocateArguments(effect, control, args_state);
      effect = elements->op()->EffectOutputCount() > 0 ? elements : effect;
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      // Load the arguments object map.
      Node* const arguments_map = jsgraph()->HeapConstant(
          handle(native_context()->strict_arguments_map(), isolate()));
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      // Actually allocate and initialize the arguments object.
      AllocationBuilder a(jsgraph(), effect, control);
      Node* properties = jsgraph()->EmptyFixedArrayConstant();
      int length = args_state_info.parameter_count() - 1;  // Minus receiver.
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      STATIC_ASSERT(JSStrictArgumentsObject::kSize == 4 * kPointerSize);
      a.Allocate(JSStrictArgumentsObject::kSize);
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      a.Store(AccessBuilder::ForMap(), arguments_map);
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      a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
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      a.Store(AccessBuilder::ForJSObjectElements(), elements);
      a.Store(AccessBuilder::ForArgumentsLength(), jsgraph()->Constant(length));
      RelaxControls(node);
      a.FinishAndChange(node);
      return Changed(node);
    } else if (type == CreateArgumentsType::kRestParameter) {
      int start_index = shared->internal_formal_parameter_count();
      // Use inline allocation for all unmapped arguments objects within inlined
      // (i.e. non-outermost) frames, independent of the object size.
      Node* effect = NodeProperties::GetEffectInput(node);
      // Choose the correct frame state and frame state info depending on
      // whether there conceptually is an arguments adaptor frame in the call
      // chain.
      Node* const args_state = GetArgumentsFrameState(frame_state);
      FrameStateInfo args_state_info = OpParameter<FrameStateInfo>(args_state);
      // Prepare element backing store to be used by the rest array.
      Node* const elements =
          AllocateRestArguments(effect, control, args_state, start_index);
      effect = elements->op()->EffectOutputCount() > 0 ? elements : effect;
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      // Load the JSArray object map.
      Node* const jsarray_map = jsgraph()->HeapConstant(handle(
          native_context()->js_array_fast_elements_map_index(), isolate()));
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      // Actually allocate and initialize the jsarray.
      AllocationBuilder a(jsgraph(), effect, control);
      Node* properties = jsgraph()->EmptyFixedArrayConstant();

      // -1 to minus receiver
      int argument_count = args_state_info.parameter_count() - 1;
      int length = std::max(0, argument_count - start_index);
      STATIC_ASSERT(JSArray::kSize == 4 * kPointerSize);
      a.Allocate(JSArray::kSize);
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      a.Store(AccessBuilder::ForMap(), jsarray_map);
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      a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
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      a.Store(AccessBuilder::ForJSObjectElements(), elements);
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      a.Store(AccessBuilder::ForJSArrayLength(PACKED_ELEMENTS),
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              jsgraph()->Constant(length));
      RelaxControls(node);
      a.FinishAndChange(node);
      return Changed(node);
    }
  }

  return NoChange();
}

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Reduction JSCreateLowering::ReduceJSCreateGeneratorObject(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateGeneratorObject, node->opcode());
  Node* const closure = NodeProperties::GetValueInput(node, 0);
  Node* const receiver = NodeProperties::GetValueInput(node, 1);
  Node* const context = NodeProperties::GetContextInput(node);
  Type* const closure_type = NodeProperties::GetType(closure);
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* const control = NodeProperties::GetControlInput(node);
  if (closure_type->IsHeapConstant()) {
    DCHECK(closure_type->AsHeapConstant()->Value()->IsJSFunction());
    Handle<JSFunction> js_function =
        Handle<JSFunction>::cast(closure_type->AsHeapConstant()->Value());
    JSFunction::EnsureHasInitialMap(js_function);
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    // Force completion of inobject slack tracking before
    // generating code to finalize the instance size.
    js_function->CompleteInobjectSlackTrackingIfActive();
    Handle<Map> initial_map(js_function->initial_map(), isolate());
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    DCHECK(initial_map->instance_type() == JS_GENERATOR_OBJECT_TYPE ||
           initial_map->instance_type() == JS_ASYNC_GENERATOR_OBJECT_TYPE);

    // Add a dependency on the {initial_map} to make sure that this code is
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    // deoptimized whenever the {initial_map} changes.
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    dependencies()->AssumeInitialMapCantChange(initial_map);

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    // Allocate a register file.
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    DCHECK(js_function->shared()->HasBytecodeArray());
    int size = js_function->shared()->bytecode_array()->register_count();
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    Node* register_file = effect =
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        AllocateElements(effect, control, HOLEY_ELEMENTS, size, NOT_TENURED);
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    // Emit code to allocate the JS[Async]GeneratorObject instance.
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    AllocationBuilder a(jsgraph(), effect, control);
    a.Allocate(initial_map->instance_size());
    Node* empty_fixed_array = jsgraph()->EmptyFixedArrayConstant();
    Node* undefined = jsgraph()->UndefinedConstant();
    a.Store(AccessBuilder::ForMap(), initial_map);
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    a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), empty_fixed_array);
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    a.Store(AccessBuilder::ForJSObjectElements(), empty_fixed_array);
    a.Store(AccessBuilder::ForJSGeneratorObjectContext(), context);
    a.Store(AccessBuilder::ForJSGeneratorObjectFunction(), closure);
    a.Store(AccessBuilder::ForJSGeneratorObjectReceiver(), receiver);
    a.Store(AccessBuilder::ForJSGeneratorObjectInputOrDebugPos(), undefined);
    a.Store(AccessBuilder::ForJSGeneratorObjectResumeMode(),
            jsgraph()->Constant(JSGeneratorObject::kNext));
    a.Store(AccessBuilder::ForJSGeneratorObjectContinuation(),
            jsgraph()->Constant(JSGeneratorObject::kGeneratorExecuting));
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    a.Store(AccessBuilder::ForJSGeneratorObjectRegisterFile(), register_file);
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    if (initial_map->instance_type() == JS_ASYNC_GENERATOR_OBJECT_TYPE) {
      a.Store(AccessBuilder::ForJSAsyncGeneratorObjectQueue(), undefined);
      a.Store(AccessBuilder::ForJSAsyncGeneratorObjectAwaitedPromise(),
              undefined);
    }

    // Handle in-object properties, too.
    for (int i = 0; i < initial_map->GetInObjectProperties(); ++i) {
      a.Store(AccessBuilder::ForJSObjectInObjectProperty(initial_map, i),
              undefined);
    }
    a.FinishAndChange(node);
    return Changed(node);
  }
  return NoChange();
}

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// Constructs an array with a variable {length} when no upper bound
// is known for the capacity.
Reduction JSCreateLowering::ReduceNewArray(Node* node, Node* length,
                                           Handle<Map> initial_map,
                                           PretenureFlag pretenure) {
  DCHECK_EQ(IrOpcode::kJSCreateArray, node->opcode());
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);

  // Constructing an Array via new Array(N) where N is an unsigned
  // integer, always creates a holey backing store.
  if (!IsHoleyElementsKind(initial_map->elements_kind())) {
    initial_map = Map::AsElementsKind(
        initial_map, GetHoleyElementsKind(initial_map->elements_kind()));
  }

  // Check that the {limit} is an unsigned integer in the valid range.
  // This has to be kept in sync with src/runtime/runtime-array.cc,
  // where this limit is protected.
  length = effect = graph()->NewNode(
      simplified()->CheckBounds(), length,
      jsgraph()->Constant(JSArray::kInitialMaxFastElementArray), effect,
      control);

  // Construct elements and properties for the resulting JSArray.
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  Node* elements = effect =
      graph()->NewNode(IsDoubleElementsKind(initial_map->elements_kind())
                           ? simplified()->NewDoubleElements(pretenure)
                           : simplified()->NewSmiOrObjectElements(pretenure),
                       length, effect, control);
538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558
  Node* properties = jsgraph()->EmptyFixedArrayConstant();

  // Perform the allocation of the actual JSArray object.
  AllocationBuilder a(jsgraph(), effect, control);
  a.Allocate(initial_map->instance_size(), pretenure);
  a.Store(AccessBuilder::ForMap(), initial_map);
  a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
  a.Store(AccessBuilder::ForJSObjectElements(), elements);
  a.Store(AccessBuilder::ForJSArrayLength(initial_map->elements_kind()),
          length);
  for (int i = 0; i < initial_map->GetInObjectProperties(); ++i) {
    a.Store(AccessBuilder::ForJSObjectInObjectProperty(initial_map, i),
            jsgraph()->UndefinedConstant());
  }
  RelaxControls(node);
  a.FinishAndChange(node);
  return Changed(node);
}

// Constructs an array with a variable {length} when an actual
// upper bound is known for the {capacity}.
559 560
Reduction JSCreateLowering::ReduceNewArray(Node* node, Node* length,
                                           int capacity,
561 562
                                           Handle<Map> initial_map,
                                           PretenureFlag pretenure) {
563 564
  DCHECK(node->opcode() == IrOpcode::kJSCreateArray ||
         node->opcode() == IrOpcode::kJSCreateEmptyLiteralArray);
565 566 567
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);

568 569 570
  // Determine the appropriate elements kind.
  ElementsKind elements_kind = initial_map->elements_kind();
  if (NodeProperties::GetType(length)->Max() > 0.0) {
571
    elements_kind = GetHoleyElementsKind(elements_kind);
572
    initial_map = Map::AsElementsKind(initial_map, elements_kind);
573
  }
574
  DCHECK(IsFastElementsKind(elements_kind));
575 576 577 578 579 580 581 582 583 584 585 586 587

  // Setup elements and properties.
  Node* elements;
  if (capacity == 0) {
    elements = jsgraph()->EmptyFixedArrayConstant();
  } else {
    elements = effect =
        AllocateElements(effect, control, elements_kind, capacity, pretenure);
  }
  Node* properties = jsgraph()->EmptyFixedArrayConstant();

  // Perform the allocation of the actual JSArray object.
  AllocationBuilder a(jsgraph(), effect, control);
588 589
  a.Allocate(initial_map->instance_size(), pretenure);
  a.Store(AccessBuilder::ForMap(), initial_map);
590
  a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
591 592
  a.Store(AccessBuilder::ForJSObjectElements(), elements);
  a.Store(AccessBuilder::ForJSArrayLength(elements_kind), length);
593 594 595 596
  for (int i = 0; i < initial_map->GetInObjectProperties(); ++i) {
    a.Store(AccessBuilder::ForJSObjectInObjectProperty(initial_map, i),
            jsgraph()->UndefinedConstant());
  }
597 598 599 600 601
  RelaxControls(node);
  a.FinishAndChange(node);
  return Changed(node);
}

602 603
Reduction JSCreateLowering::ReduceNewArray(Node* node,
                                           std::vector<Node*> values,
604 605
                                           Handle<Map> initial_map,
                                           PretenureFlag pretenure) {
606 607 608 609
  DCHECK_EQ(IrOpcode::kJSCreateArray, node->opcode());
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);

610 611
  // Determine the appropriate elements kind.
  ElementsKind elements_kind = initial_map->elements_kind();
612 613 614 615 616
  DCHECK(IsFastElementsKind(elements_kind));

  // Check {values} based on the {elements_kind}. These checks are guarded
  // by the {elements_kind} feedback on the {site}, so it's safe to just
  // deoptimize in this case.
617
  if (IsSmiElementsKind(elements_kind)) {
618 619 620 621 622 623
    for (auto& value : values) {
      if (!NodeProperties::GetType(value)->Is(Type::SignedSmall())) {
        value = effect =
            graph()->NewNode(simplified()->CheckSmi(), value, effect, control);
      }
    }
624
  } else if (IsDoubleElementsKind(elements_kind)) {
625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642
    for (auto& value : values) {
      if (!NodeProperties::GetType(value)->Is(Type::Number())) {
        value = effect = graph()->NewNode(simplified()->CheckNumber(), value,
                                          effect, control);
      }
      // Make sure we do not store signaling NaNs into double arrays.
      value = graph()->NewNode(simplified()->NumberSilenceNaN(), value);
    }
  }

  // Setup elements, properties and length.
  Node* elements = effect =
      AllocateElements(effect, control, elements_kind, values, pretenure);
  Node* properties = jsgraph()->EmptyFixedArrayConstant();
  Node* length = jsgraph()->Constant(static_cast<int>(values.size()));

  // Perform the allocation of the actual JSArray object.
  AllocationBuilder a(jsgraph(), effect, control);
643 644
  a.Allocate(initial_map->instance_size(), pretenure);
  a.Store(AccessBuilder::ForMap(), initial_map);
645
  a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
646 647
  a.Store(AccessBuilder::ForJSObjectElements(), elements);
  a.Store(AccessBuilder::ForJSArrayLength(elements_kind), length);
648 649 650 651
  for (int i = 0; i < initial_map->GetInObjectProperties(); ++i) {
    a.Store(AccessBuilder::ForJSObjectInObjectProperty(initial_map, i),
            jsgraph()->UndefinedConstant());
  }
652 653 654 655 656
  RelaxControls(node);
  a.FinishAndChange(node);
  return Changed(node);
}

657 658 659 660
Reduction JSCreateLowering::ReduceNewArrayToStubCall(
    Node* node, Handle<AllocationSite> site) {
  CreateArrayParameters const& p = CreateArrayParametersOf(node->op());
  int const arity = static_cast<int>(p.arity());
661 662 663
  Node* target = NodeProperties::GetValueInput(node, 0);
  Node* new_target = NodeProperties::GetValueInput(node, 1);
  Type* new_target_type = NodeProperties::GetType(new_target);
664 665
  Node* type_info = site.is_null() ? jsgraph()->UndefinedConstant()
                                   : jsgraph()->HeapConstant(site);
666

667 668
  ElementsKind elements_kind =
      site.is_null() ? GetInitialFastElementsKind() : site->GetElementsKind();
669
  AllocationSiteOverrideMode override_mode =
670 671 672
      (site.is_null() || AllocationSite::ShouldTrack(elements_kind))
          ? DISABLE_ALLOCATION_SITES
          : DONT_OVERRIDE;
673

674 675 676 677 678 679 680
  // The Array constructor can only trigger an observable side-effect
  // if the new.target may be a proxy.
  Operator::Properties const properties =
      (new_target != target || new_target_type->Maybe(Type::Proxy()))
          ? Operator::kNoDeopt
          : Operator::kNoDeopt | Operator::kNoWrite;

681 682 683 684
  if (arity == 0) {
    ArrayNoArgumentConstructorStub stub(isolate(), elements_kind,
                                        override_mode);
    CallDescriptor* desc = Linkage::GetStubCallDescriptor(
685 686
        isolate(), graph()->zone(), stub.GetCallInterfaceDescriptor(),
        arity + 1, CallDescriptor::kNeedsFrameState, properties);
687
    node->ReplaceInput(0, jsgraph()->HeapConstant(stub.GetCode()));
688 689
    node->InsertInput(graph()->zone(), 2, type_info);
    node->InsertInput(graph()->zone(), 3, jsgraph()->Constant(arity));
690 691 692
    node->InsertInput(graph()->zone(), 4, jsgraph()->UndefinedConstant());
    NodeProperties::ChangeOp(node, common()->Call(desc));
  } else if (arity == 1) {
693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714
    // Require elements kind to "go holey".
    ArraySingleArgumentConstructorStub stub(
        isolate(), GetHoleyElementsKind(elements_kind), override_mode);
    CallDescriptor* desc = Linkage::GetStubCallDescriptor(
        isolate(), graph()->zone(), stub.GetCallInterfaceDescriptor(),
        arity + 1, CallDescriptor::kNeedsFrameState, properties);
    node->ReplaceInput(0, jsgraph()->HeapConstant(stub.GetCode()));
    node->InsertInput(graph()->zone(), 2, type_info);
    node->InsertInput(graph()->zone(), 3, jsgraph()->Constant(arity));
    node->InsertInput(graph()->zone(), 4, jsgraph()->UndefinedConstant());
    NodeProperties::ChangeOp(node, common()->Call(desc));
  } else {
    DCHECK_GT(arity, 1);
    ArrayNArgumentsConstructorStub stub(isolate());
    CallDescriptor* desc = Linkage::GetStubCallDescriptor(
        isolate(), graph()->zone(), stub.GetCallInterfaceDescriptor(),
        arity + 1, CallDescriptor::kNeedsFrameState);
    node->ReplaceInput(0, jsgraph()->HeapConstant(stub.GetCode()));
    node->InsertInput(graph()->zone(), 2, type_info);
    node->InsertInput(graph()->zone(), 3, jsgraph()->Constant(arity));
    node->InsertInput(graph()->zone(), 4, jsgraph()->UndefinedConstant());
    NodeProperties::ChangeOp(node, common()->Call(desc));
715 716 717 718
  }
  return Changed(node);
}

719 720 721
Reduction JSCreateLowering::ReduceJSCreateArray(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateArray, node->opcode());
  CreateArrayParameters const& p = CreateArrayParametersOf(node->op());
722 723 724 725
  int const arity = static_cast<int>(p.arity());
  Handle<AllocationSite> const site = p.site();
  PretenureFlag pretenure = NOT_TENURED;
  Handle<JSFunction> constructor(native_context()->array_function(), isolate());
726 727
  Node* target = NodeProperties::GetValueInput(node, 0);
  Node* new_target = NodeProperties::GetValueInput(node, 1);
728 729 730
  Type* new_target_type = (target == new_target)
                              ? Type::HeapConstant(constructor, zone())
                              : NodeProperties::GetType(new_target);
731

732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750
  // Extract original constructor function.
  if (new_target_type->IsHeapConstant() &&
      new_target_type->AsHeapConstant()->Value()->IsJSFunction()) {
    Handle<JSFunction> original_constructor =
        Handle<JSFunction>::cast(new_target_type->AsHeapConstant()->Value());
    DCHECK(constructor->IsConstructor());
    DCHECK(original_constructor->IsConstructor());

    // Check if we can inline the allocation.
    if (IsAllocationInlineable(constructor, original_constructor)) {
      // Force completion of inobject slack tracking before
      // generating code to finalize the instance size.
      original_constructor->CompleteInobjectSlackTrackingIfActive();
      Handle<Map> initial_map(original_constructor->initial_map(), isolate());

      // Add a dependency on the {initial_map} to make sure that this code is
      // deoptimized whenever the {initial_map} changes.
      dependencies()->AssumeInitialMapCantChange(initial_map);

751 752 753 754
      // Tells whether we are protected by either the {site} or a
      // protector cell to do certain speculative optimizations.
      bool can_inline_call = false;

755 756 757 758 759 760
      // Check if we have a feedback {site} on the {node}.
      if (!site.is_null()) {
        ElementsKind elements_kind = site->GetElementsKind();
        if (initial_map->elements_kind() != elements_kind) {
          initial_map = Map::AsElementsKind(initial_map, elements_kind);
        }
761
        can_inline_call = site->CanInlineCall();
762 763 764 765
        pretenure = site->GetPretenureMode();

        dependencies()->AssumeTransitionStable(site);
        dependencies()->AssumeTenuringDecision(site);
766 767
      } else {
        can_inline_call = isolate()->IsArrayConstructorIntact();
768
      }
769

770
      if (arity == 0) {
771 772
        Node* length = jsgraph()->ZeroConstant();
        int capacity = JSArray::kPreallocatedArrayElements;
773 774
        return ReduceNewArray(node, length, capacity, initial_map, pretenure);
      } else if (arity == 1) {
775 776 777 778 779
        Node* length = NodeProperties::GetValueInput(node, 2);
        Type* length_type = NodeProperties::GetType(length);
        if (!length_type->Maybe(Type::Number())) {
          // Handle the single argument case, where we know that the value
          // cannot be a valid Array length.
780 781 782 783 784 785
          ElementsKind elements_kind = initial_map->elements_kind();
          elements_kind = GetMoreGeneralElementsKind(
              elements_kind, IsHoleyElementsKind(elements_kind)
                                 ? HOLEY_ELEMENTS
                                 : PACKED_ELEMENTS);
          initial_map = Map::AsElementsKind(initial_map, elements_kind);
786 787
          return ReduceNewArray(node, std::vector<Node*>{length}, initial_map,
                                pretenure);
788 789 790 791 792
        }
        if (length_type->Is(Type::SignedSmall()) && length_type->Min() >= 0 &&
            length_type->Max() <= kElementLoopUnrollLimit &&
            length_type->Min() == length_type->Max()) {
          int capacity = static_cast<int>(length_type->Max());
793
          return ReduceNewArray(node, length, capacity, initial_map, pretenure);
794
        }
795 796 797
        if (length_type->Maybe(Type::UnsignedSmall()) && can_inline_call) {
          return ReduceNewArray(node, length, initial_map, pretenure);
        }
798 799 800 801
      } else if (arity <= JSArray::kInitialMaxFastElementArray) {
        // Gather the values to store into the newly created array.
        bool values_all_smis = true, values_all_numbers = true,
             values_any_nonnumber = false;
802 803
        std::vector<Node*> values;
        values.reserve(p.arity());
804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832
        for (int i = 0; i < arity; ++i) {
          Node* value = NodeProperties::GetValueInput(node, 2 + i);
          Type* value_type = NodeProperties::GetType(value);
          if (!value_type->Is(Type::SignedSmall())) {
            values_all_smis = false;
          }
          if (!value_type->Is(Type::Number())) {
            values_all_numbers = false;
          }
          if (!value_type->Maybe(Type::Number())) {
            values_any_nonnumber = true;
          }
          values.push_back(value);
        }

        // Try to figure out the ideal elements kind statically.
        ElementsKind elements_kind = initial_map->elements_kind();
        if (values_all_smis) {
          // Smis can be stored with any elements kind.
        } else if (values_all_numbers) {
          elements_kind = GetMoreGeneralElementsKind(
              elements_kind, IsHoleyElementsKind(elements_kind)
                                 ? HOLEY_DOUBLE_ELEMENTS
                                 : PACKED_DOUBLE_ELEMENTS);
        } else if (values_any_nonnumber) {
          elements_kind = GetMoreGeneralElementsKind(
              elements_kind, IsHoleyElementsKind(elements_kind)
                                 ? HOLEY_ELEMENTS
                                 : PACKED_ELEMENTS);
833
        } else if (!can_inline_call) {
834 835 836 837 838 839
          // We have some crazy combination of types for the {values} where
          // there's no clear decision on the elements kind statically. And
          // we don't have a protection against deoptimization loops for the
          // checks that are introduced in the call to ReduceNewArray, so
          // we cannot inline this invocation of the Array constructor here.
          return NoChange();
840
        }
841 842 843
        initial_map = Map::AsElementsKind(initial_map, elements_kind);

        return ReduceNewArray(node, values, initial_map, pretenure);
844 845 846 847
      }
    }
  }

848 849 850
  // TODO(bmeurer): Optimize the subclassing case.
  if (target != new_target) return NoChange();

851
  return ReduceNewArrayToStubCall(node, site);
852 853
}

854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893
Reduction JSCreateLowering::ReduceJSCreateBoundFunction(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateBoundFunction, node->opcode());
  CreateBoundFunctionParameters const& p =
      CreateBoundFunctionParametersOf(node->op());
  int const arity = static_cast<int>(p.arity());
  Handle<Map> const map = p.map();
  Node* bound_target_function = NodeProperties::GetValueInput(node, 0);
  Node* bound_this = NodeProperties::GetValueInput(node, 1);
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);

  // Create the [[BoundArguments]] for the result.
  Node* bound_arguments = jsgraph()->EmptyFixedArrayConstant();
  if (arity > 0) {
    AllocationBuilder a(jsgraph(), effect, control);
    a.AllocateArray(arity, factory()->fixed_array_map());
    for (int i = 0; i < arity; ++i) {
      a.Store(AccessBuilder::ForFixedArraySlot(i),
              NodeProperties::GetValueInput(node, 2 + i));
    }
    bound_arguments = effect = a.Finish();
  }

  // Create the JSBoundFunction result.
  AllocationBuilder a(jsgraph(), effect, control);
  a.Allocate(JSBoundFunction::kSize, NOT_TENURED, Type::BoundFunction());
  a.Store(AccessBuilder::ForMap(), map);
  a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(),
          jsgraph()->EmptyFixedArrayConstant());
  a.Store(AccessBuilder::ForJSObjectElements(),
          jsgraph()->EmptyFixedArrayConstant());
  a.Store(AccessBuilder::ForJSBoundFunctionBoundTargetFunction(),
          bound_target_function);
  a.Store(AccessBuilder::ForJSBoundFunctionBoundThis(), bound_this);
  a.Store(AccessBuilder::ForJSBoundFunctionBoundArguments(), bound_arguments);
  RelaxControls(node);
  a.FinishAndChange(node);
  return Changed(node);
}

894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915
Reduction JSCreateLowering::ReduceJSCreateClosure(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateClosure, node->opcode());
  CreateClosureParameters const& p = CreateClosureParametersOf(node->op());
  Handle<SharedFunctionInfo> shared = p.shared_info();
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);
  Node* context = NodeProperties::GetContextInput(node);

  // Use inline allocation of closures only for instantiation sites that have
  // seen more than one instantiation, this simplifies the generated code and
  // also serves as a heuristic of which allocation sites benefit from it.
  FeedbackSlot slot(FeedbackVector::ToSlot(p.feedback().index()));
  Handle<Cell> vector_cell(Cell::cast(p.feedback().vector()->Get(slot)));
  if (vector_cell->map() == isolate()->heap()->many_closures_cell_map()) {
    Handle<Map> function_map(
        Map::cast(native_context()->get(shared->function_map_index())));
    Node* lazy_compile_builtin = jsgraph()->HeapConstant(
        handle(isolate()->builtins()->builtin(Builtins::kCompileLazy)));
    DCHECK(!function_map->IsInobjectSlackTrackingInProgress());
    DCHECK(!function_map->is_dictionary_map());

    // Emit code to allocate the JSFunction instance.
916
    STATIC_ASSERT(JSFunction::kSizeWithoutPrototype == 7 * kPointerSize);
917 918 919 920 921 922 923 924 925 926 927
    AllocationBuilder a(jsgraph(), effect, control);
    a.Allocate(function_map->instance_size());
    a.Store(AccessBuilder::ForMap(), function_map);
    a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(),
            jsgraph()->EmptyFixedArrayConstant());
    a.Store(AccessBuilder::ForJSObjectElements(),
            jsgraph()->EmptyFixedArrayConstant());
    a.Store(AccessBuilder::ForJSFunctionSharedFunctionInfo(), shared);
    a.Store(AccessBuilder::ForJSFunctionContext(), context);
    a.Store(AccessBuilder::ForJSFunctionFeedbackVector(), vector_cell);
    a.Store(AccessBuilder::ForJSFunctionCode(), lazy_compile_builtin);
928 929 930 931 932 933
    STATIC_ASSERT(JSFunction::kSizeWithoutPrototype == 7 * kPointerSize);
    if (function_map->has_prototype_slot()) {
      a.Store(AccessBuilder::ForJSFunctionPrototypeOrInitialMap(),
              jsgraph()->TheHoleConstant());
      STATIC_ASSERT(JSFunction::kSizeWithPrototype == 8 * kPointerSize);
    }
934 935 936 937 938 939 940 941 942 943 944 945
    for (int i = 0; i < function_map->GetInObjectProperties(); i++) {
      a.Store(AccessBuilder::ForJSObjectInObjectProperty(function_map, i),
              jsgraph()->UndefinedConstant());
    }
    RelaxControls(node);
    a.FinishAndChange(node);
    return Changed(node);
  }

  return NoChange();
}

946 947 948 949 950 951
Reduction JSCreateLowering::ReduceJSCreateIterResultObject(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateIterResultObject, node->opcode());
  Node* value = NodeProperties::GetValueInput(node, 0);
  Node* done = NodeProperties::GetValueInput(node, 1);
  Node* effect = NodeProperties::GetEffectInput(node);

952 953
  Node* iterator_result_map = jsgraph()->HeapConstant(
      handle(native_context()->iterator_result_map(), isolate()));
954 955 956 957 958

  // Emit code to allocate the JSIteratorResult instance.
  AllocationBuilder a(jsgraph(), effect, graph()->start());
  a.Allocate(JSIteratorResult::kSize);
  a.Store(AccessBuilder::ForMap(), iterator_result_map);
959
  a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(),
960 961 962 963 964 965 966 967 968 969
          jsgraph()->EmptyFixedArrayConstant());
  a.Store(AccessBuilder::ForJSObjectElements(),
          jsgraph()->EmptyFixedArrayConstant());
  a.Store(AccessBuilder::ForJSIteratorResultValue(), value);
  a.Store(AccessBuilder::ForJSIteratorResultDone(), done);
  STATIC_ASSERT(JSIteratorResult::kSize == 5 * kPointerSize);
  a.FinishAndChange(node);
  return Changed(node);
}

970 971 972 973 974 975 976 977 978 979 980 981 982
Reduction JSCreateLowering::ReduceJSCreateKeyValueArray(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateKeyValueArray, node->opcode());
  Node* key = NodeProperties::GetValueInput(node, 0);
  Node* value = NodeProperties::GetValueInput(node, 1);
  Node* effect = NodeProperties::GetEffectInput(node);

  Node* array_map = jsgraph()->HeapConstant(
      handle(native_context()->js_array_fast_elements_map_index()));
  Node* properties = jsgraph()->EmptyFixedArrayConstant();
  Node* length = jsgraph()->Constant(2);

  AllocationBuilder aa(jsgraph(), effect, graph()->start());
  aa.AllocateArray(2, factory()->fixed_array_map());
983
  aa.Store(AccessBuilder::ForFixedArrayElement(PACKED_ELEMENTS),
984
           jsgraph()->Constant(0), key);
985
  aa.Store(AccessBuilder::ForFixedArrayElement(PACKED_ELEMENTS),
986 987 988 989 990 991
           jsgraph()->Constant(1), value);
  Node* elements = aa.Finish();

  AllocationBuilder a(jsgraph(), elements, graph()->start());
  a.Allocate(JSArray::kSize);
  a.Store(AccessBuilder::ForMap(), array_map);
992
  a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
993
  a.Store(AccessBuilder::ForJSObjectElements(), elements);
994
  a.Store(AccessBuilder::ForJSArrayLength(PACKED_ELEMENTS), length);
995 996 997 998 999
  STATIC_ASSERT(JSArray::kSize == 4 * kPointerSize);
  a.FinishAndChange(node);
  return Changed(node);
}

1000
Reduction JSCreateLowering::ReduceJSCreateLiteralArrayOrObject(Node* node) {
1001 1002 1003 1004 1005 1006
  DCHECK(node->opcode() == IrOpcode::kJSCreateLiteralArray ||
         node->opcode() == IrOpcode::kJSCreateLiteralObject);
  CreateLiteralParameters const& p = CreateLiteralParametersOf(node->op());
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);

1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020
  Handle<Object> feedback(p.feedback().vector()->Get(p.feedback().slot()),
                          isolate());
  if (feedback->IsAllocationSite()) {
    Handle<AllocationSite> site = Handle<AllocationSite>::cast(feedback);
    Handle<JSObject> boilerplate(site->boilerplate(), isolate());
    int max_properties = kMaxFastLiteralProperties;
    if (IsFastLiteral(boilerplate, kMaxFastLiteralDepth, &max_properties)) {
      AllocationSiteUsageContext site_context(isolate(), site, false);
      site_context.EnterNewScope();
      Node* value = effect =
          AllocateFastLiteral(effect, control, boilerplate, &site_context);
      site_context.ExitScope(site, boilerplate);
      ReplaceWithValue(node, value, effect, control);
      return Replace(value);
1021 1022
    }
  }
1023 1024
  return NoChange();
}
1025

1026
Reduction JSCreateLowering::ReduceJSCreateEmptyLiteralArray(Node* node) {
1027 1028 1029 1030 1031 1032 1033
  DCHECK_EQ(IrOpcode::kJSCreateEmptyLiteralArray, node->opcode());
  FeedbackParameter const& p = FeedbackParameterOf(node->op());
  Handle<Object> feedback(p.feedback().vector()->Get(p.feedback().slot()),
                          isolate());
  if (feedback->IsAllocationSite()) {
    Handle<AllocationSite> site = Handle<AllocationSite>::cast(feedback);
    DCHECK(!site->PointsToLiteral());
1034 1035 1036 1037 1038 1039
    Handle<Map> const initial_map(
        native_context()->GetInitialJSArrayMap(site->GetElementsKind()),
        isolate());
    PretenureFlag const pretenure = site->GetPretenureMode();
    dependencies()->AssumeTransitionStable(site);
    dependencies()->AssumeTenuringDecision(site);
1040
    Node* length = jsgraph()->ZeroConstant();
1041
    return ReduceNewArray(node, length, 0, initial_map, pretenure);
1042 1043 1044 1045
  }
  return NoChange();
}

1046
Reduction JSCreateLowering::ReduceJSCreateEmptyLiteralObject(Node* node) {
1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076
  DCHECK_EQ(IrOpcode::kJSCreateEmptyLiteralObject, node->opcode());
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);

  // Retrieve the initial map for the object.
  Handle<Map> map = factory()->ObjectLiteralMapFromCache(native_context(), 0);
  DCHECK(!map->is_dictionary_map());
  DCHECK(!map->IsInobjectSlackTrackingInProgress());
  Node* js_object_map = jsgraph()->HeapConstant(map);

  // Setup elements and properties.
  Node* elements = jsgraph()->EmptyFixedArrayConstant();
  Node* properties = jsgraph()->EmptyFixedArrayConstant();

  // Perform the allocation of the actual JSArray object.
  AllocationBuilder a(jsgraph(), effect, control);
  a.Allocate(map->instance_size());
  a.Store(AccessBuilder::ForMap(), js_object_map);
  a.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
  a.Store(AccessBuilder::ForJSObjectElements(), elements);
  for (int i = 0; i < map->GetInObjectProperties(); i++) {
    a.Store(AccessBuilder::ForJSObjectInObjectProperty(map, i),
            jsgraph()->UndefinedConstant());
  }

  RelaxControls(node);
  a.FinishAndChange(node);
  return Changed(node);
}

1077
Reduction JSCreateLowering::ReduceJSCreateLiteralRegExp(Node* node) {
1078
  DCHECK_EQ(IrOpcode::kJSCreateLiteralRegExp, node->opcode());
1079 1080 1081 1082
  CreateLiteralParameters const& p = CreateLiteralParametersOf(node->op());
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);

1083 1084 1085 1086 1087 1088 1089
  Handle<Object> feedback(p.feedback().vector()->Get(p.feedback().slot()),
                          isolate());
  if (feedback->IsJSRegExp()) {
    Handle<JSRegExp> boilerplate = Handle<JSRegExp>::cast(feedback);
    Node* value = effect = AllocateLiteralRegExp(effect, control, boilerplate);
    ReplaceWithValue(node, value, effect, control);
    return Replace(value);
1090 1091 1092 1093
  }
  return NoChange();
}

1094 1095
Reduction JSCreateLowering::ReduceJSCreateFunctionContext(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateFunctionContext, node->opcode());
1096 1097 1098 1099
  const CreateFunctionContextParameters& parameters =
      CreateFunctionContextParametersOf(node->op());
  int slot_count = parameters.slot_count();
  ScopeType scope_type = parameters.scope_type();
1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111
  Node* const closure = NodeProperties::GetValueInput(node, 0);

  // Use inline allocation for function contexts up to a size limit.
  if (slot_count < kFunctionContextAllocationLimit) {
    // JSCreateFunctionContext[slot_count < limit]](fun)
    Node* effect = NodeProperties::GetEffectInput(node);
    Node* control = NodeProperties::GetControlInput(node);
    Node* context = NodeProperties::GetContextInput(node);
    Node* extension = jsgraph()->TheHoleConstant();
    AllocationBuilder a(jsgraph(), effect, control);
    STATIC_ASSERT(Context::MIN_CONTEXT_SLOTS == 4);  // Ensure fully covered.
    int context_length = slot_count + Context::MIN_CONTEXT_SLOTS;
1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123
    Handle<Map> map;
    switch (scope_type) {
      case EVAL_SCOPE:
        map = factory()->eval_context_map();
        break;
      case FUNCTION_SCOPE:
        map = factory()->function_context_map();
        break;
      default:
        UNREACHABLE();
    }
    a.AllocateArray(context_length, map);
1124 1125 1126 1127
    a.Store(AccessBuilder::ForContextSlot(Context::CLOSURE_INDEX), closure);
    a.Store(AccessBuilder::ForContextSlot(Context::PREVIOUS_INDEX), context);
    a.Store(AccessBuilder::ForContextSlot(Context::EXTENSION_INDEX), extension);
    a.Store(AccessBuilder::ForContextSlot(Context::NATIVE_CONTEXT_INDEX),
1128
            jsgraph()->HeapConstant(native_context()));
1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141
    for (int i = Context::MIN_CONTEXT_SLOTS; i < context_length; ++i) {
      a.Store(AccessBuilder::ForContextSlot(i), jsgraph()->UndefinedConstant());
    }
    RelaxControls(node);
    a.FinishAndChange(node);
    return Changed(node);
  }

  return NoChange();
}

Reduction JSCreateLowering::ReduceJSCreateWithContext(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateWithContext, node->opcode());
1142
  Handle<ScopeInfo> scope_info = OpParameter<Handle<ScopeInfo>>(node);
1143 1144 1145 1146 1147
  Node* object = NodeProperties::GetValueInput(node, 0);
  Node* closure = NodeProperties::GetValueInput(node, 1);
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);
  Node* context = NodeProperties::GetContextInput(node);
1148 1149 1150 1151 1152 1153 1154 1155 1156

  AllocationBuilder aa(jsgraph(), effect, control);
  aa.Allocate(ContextExtension::kSize);
  aa.Store(AccessBuilder::ForMap(), factory()->context_extension_map());
  aa.Store(AccessBuilder::ForContextExtensionScopeInfo(), scope_info);
  aa.Store(AccessBuilder::ForContextExtensionExtension(), object);
  Node* extension = aa.Finish();

  AllocationBuilder a(jsgraph(), extension, control);
1157 1158 1159 1160
  STATIC_ASSERT(Context::MIN_CONTEXT_SLOTS == 4);  // Ensure fully covered.
  a.AllocateArray(Context::MIN_CONTEXT_SLOTS, factory()->with_context_map());
  a.Store(AccessBuilder::ForContextSlot(Context::CLOSURE_INDEX), closure);
  a.Store(AccessBuilder::ForContextSlot(Context::PREVIOUS_INDEX), context);
1161
  a.Store(AccessBuilder::ForContextSlot(Context::EXTENSION_INDEX), extension);
1162
  a.Store(AccessBuilder::ForContextSlot(Context::NATIVE_CONTEXT_INDEX),
1163
          jsgraph()->HeapConstant(native_context()));
1164 1165 1166 1167 1168 1169 1170
  RelaxControls(node);
  a.FinishAndChange(node);
  return Changed(node);
}

Reduction JSCreateLowering::ReduceJSCreateCatchContext(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateCatchContext, node->opcode());
1171 1172
  const CreateCatchContextParameters& parameters =
      CreateCatchContextParametersOf(node->op());
1173 1174 1175 1176 1177
  Node* exception = NodeProperties::GetValueInput(node, 0);
  Node* closure = NodeProperties::GetValueInput(node, 1);
  Node* effect = NodeProperties::GetEffectInput(node);
  Node* control = NodeProperties::GetControlInput(node);
  Node* context = NodeProperties::GetContextInput(node);
1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188

  AllocationBuilder aa(jsgraph(), effect, control);
  aa.Allocate(ContextExtension::kSize);
  aa.Store(AccessBuilder::ForMap(), factory()->context_extension_map());
  aa.Store(AccessBuilder::ForContextExtensionScopeInfo(),
           parameters.scope_info());
  aa.Store(AccessBuilder::ForContextExtensionExtension(),
           parameters.catch_name());
  Node* extension = aa.Finish();

  AllocationBuilder a(jsgraph(), extension, control);
1189 1190 1191 1192 1193
  STATIC_ASSERT(Context::MIN_CONTEXT_SLOTS == 4);  // Ensure fully covered.
  a.AllocateArray(Context::MIN_CONTEXT_SLOTS + 1,
                  factory()->catch_context_map());
  a.Store(AccessBuilder::ForContextSlot(Context::CLOSURE_INDEX), closure);
  a.Store(AccessBuilder::ForContextSlot(Context::PREVIOUS_INDEX), context);
1194
  a.Store(AccessBuilder::ForContextSlot(Context::EXTENSION_INDEX), extension);
1195
  a.Store(AccessBuilder::ForContextSlot(Context::NATIVE_CONTEXT_INDEX),
1196
          jsgraph()->HeapConstant(native_context()));
1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216
  a.Store(AccessBuilder::ForContextSlot(Context::THROWN_OBJECT_INDEX),
          exception);
  RelaxControls(node);
  a.FinishAndChange(node);
  return Changed(node);
}

Reduction JSCreateLowering::ReduceJSCreateBlockContext(Node* node) {
  DCHECK_EQ(IrOpcode::kJSCreateBlockContext, node->opcode());
  Handle<ScopeInfo> scope_info = OpParameter<Handle<ScopeInfo>>(node);
  int const context_length = scope_info->ContextLength();
  Node* const closure = NodeProperties::GetValueInput(node, 0);

  // Use inline allocation for block contexts up to a size limit.
  if (context_length < kBlockContextAllocationLimit) {
    // JSCreateBlockContext[scope[length < limit]](fun)
    Node* effect = NodeProperties::GetEffectInput(node);
    Node* control = NodeProperties::GetControlInput(node);
    Node* context = NodeProperties::GetContextInput(node);
    Node* extension = jsgraph()->Constant(scope_info);
1217

1218 1219 1220 1221 1222 1223 1224
    AllocationBuilder a(jsgraph(), effect, control);
    STATIC_ASSERT(Context::MIN_CONTEXT_SLOTS == 4);  // Ensure fully covered.
    a.AllocateArray(context_length, factory()->block_context_map());
    a.Store(AccessBuilder::ForContextSlot(Context::CLOSURE_INDEX), closure);
    a.Store(AccessBuilder::ForContextSlot(Context::PREVIOUS_INDEX), context);
    a.Store(AccessBuilder::ForContextSlot(Context::EXTENSION_INDEX), extension);
    a.Store(AccessBuilder::ForContextSlot(Context::NATIVE_CONTEXT_INDEX),
1225
            jsgraph()->HeapConstant(native_context()));
1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253
    for (int i = Context::MIN_CONTEXT_SLOTS; i < context_length; ++i) {
      a.Store(AccessBuilder::ForContextSlot(i), jsgraph()->UndefinedConstant());
    }
    RelaxControls(node);
    a.FinishAndChange(node);
    return Changed(node);
  }

  return NoChange();
}

// Helper that allocates a FixedArray holding argument values recorded in the
// given {frame_state}. Serves as backing store for JSCreateArguments nodes.
Node* JSCreateLowering::AllocateArguments(Node* effect, Node* control,
                                          Node* frame_state) {
  FrameStateInfo state_info = OpParameter<FrameStateInfo>(frame_state);
  int argument_count = state_info.parameter_count() - 1;  // Minus receiver.
  if (argument_count == 0) return jsgraph()->EmptyFixedArrayConstant();

  // Prepare an iterator over argument values recorded in the frame state.
  Node* const parameters = frame_state->InputAt(kFrameStateParametersInput);
  StateValuesAccess parameters_access(parameters);
  auto parameters_it = ++parameters_access.begin();

  // Actually allocate the backing store.
  AllocationBuilder a(jsgraph(), effect, control);
  a.AllocateArray(argument_count, factory()->fixed_array_map());
  for (int i = 0; i < argument_count; ++i, ++parameters_it) {
1254
    DCHECK_NOT_NULL((*parameters_it).node);
1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283
    a.Store(AccessBuilder::ForFixedArraySlot(i), (*parameters_it).node);
  }
  return a.Finish();
}

// Helper that allocates a FixedArray holding argument values recorded in the
// given {frame_state}. Serves as backing store for JSCreateArguments nodes.
Node* JSCreateLowering::AllocateRestArguments(Node* effect, Node* control,
                                              Node* frame_state,
                                              int start_index) {
  FrameStateInfo state_info = OpParameter<FrameStateInfo>(frame_state);
  int argument_count = state_info.parameter_count() - 1;  // Minus receiver.
  int num_elements = std::max(0, argument_count - start_index);
  if (num_elements == 0) return jsgraph()->EmptyFixedArrayConstant();

  // Prepare an iterator over argument values recorded in the frame state.
  Node* const parameters = frame_state->InputAt(kFrameStateParametersInput);
  StateValuesAccess parameters_access(parameters);
  auto parameters_it = ++parameters_access.begin();

  // Skip unused arguments.
  for (int i = 0; i < start_index; i++) {
    ++parameters_it;
  }

  // Actually allocate the backing store.
  AllocationBuilder a(jsgraph(), effect, control);
  a.AllocateArray(num_elements, factory()->fixed_array_map());
  for (int i = 0; i < num_elements; ++i, ++parameters_it) {
1284
    DCHECK_NOT_NULL((*parameters_it).node);
1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313
    a.Store(AccessBuilder::ForFixedArraySlot(i), (*parameters_it).node);
  }
  return a.Finish();
}

// Helper that allocates a FixedArray serving as a parameter map for values
// recorded in the given {frame_state}. Some elements map to slots within the
// given {context}. Serves as backing store for JSCreateArguments nodes.
Node* JSCreateLowering::AllocateAliasedArguments(
    Node* effect, Node* control, Node* frame_state, Node* context,
    Handle<SharedFunctionInfo> shared, bool* has_aliased_arguments) {
  FrameStateInfo state_info = OpParameter<FrameStateInfo>(frame_state);
  int argument_count = state_info.parameter_count() - 1;  // Minus receiver.
  if (argument_count == 0) return jsgraph()->EmptyFixedArrayConstant();

  // If there is no aliasing, the arguments object elements are not special in
  // any way, we can just return an unmapped backing store instead.
  int parameter_count = shared->internal_formal_parameter_count();
  if (parameter_count == 0) {
    return AllocateArguments(effect, control, frame_state);
  }

  // Calculate number of argument values being aliased/mapped.
  int mapped_count = Min(argument_count, parameter_count);
  *has_aliased_arguments = true;

  // Prepare an iterator over argument values recorded in the frame state.
  Node* const parameters = frame_state->InputAt(kFrameStateParametersInput);
  StateValuesAccess parameters_access(parameters);
1314
  auto parameters_it = ++parameters_access.begin();
1315 1316 1317 1318 1319 1320

  // The unmapped argument values recorded in the frame state are stored yet
  // another indirection away and then linked into the parameter map below,
  // whereas mapped argument values are replaced with a hole instead.
  AllocationBuilder aa(jsgraph(), effect, control);
  aa.AllocateArray(argument_count, factory()->fixed_array_map());
1321
  for (int i = 0; i < mapped_count; ++i, ++parameters_it) {
1322 1323
    aa.Store(AccessBuilder::ForFixedArraySlot(i), jsgraph()->TheHoleConstant());
  }
1324 1325 1326
  for (int i = mapped_count; i < argument_count; ++i, ++parameters_it) {
    DCHECK_NOT_NULL((*parameters_it).node);
    aa.Store(AccessBuilder::ForFixedArraySlot(i), (*parameters_it).node);
1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341
  }
  Node* arguments = aa.Finish();

  // Actually allocate the backing store.
  AllocationBuilder a(jsgraph(), arguments, control);
  a.AllocateArray(mapped_count + 2, factory()->sloppy_arguments_elements_map());
  a.Store(AccessBuilder::ForFixedArraySlot(0), context);
  a.Store(AccessBuilder::ForFixedArraySlot(1), arguments);
  for (int i = 0; i < mapped_count; ++i) {
    int idx = Context::MIN_CONTEXT_SLOTS + parameter_count - 1 - i;
    a.Store(AccessBuilder::ForFixedArraySlot(i + 2), jsgraph()->Constant(idx));
  }
  return a.Finish();
}

1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353
// Helper that allocates a FixedArray serving as a parameter map for values
// unknown at compile-time, the true {arguments_length} and {arguments_frame}
// values can only be determined dynamically at run-time and are provided.
// Serves as backing store for JSCreateArguments nodes.
Node* JSCreateLowering::AllocateAliasedArguments(
    Node* effect, Node* control, Node* context, Node* arguments_frame,
    Node* arguments_length, Handle<SharedFunctionInfo> shared,
    bool* has_aliased_arguments) {
  // If there is no aliasing, the arguments object elements are not
  // special in any way, we can just return an unmapped backing store.
  int parameter_count = shared->internal_formal_parameter_count();
  if (parameter_count == 0) {
1354
    return graph()->NewNode(simplified()->NewArgumentsElements(0),
1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368
                            arguments_frame, arguments_length, effect);
  }

  // From here on we are going to allocate a mapped (aka. aliased) elements
  // backing store. We do not statically know how many arguments exist, but
  // dynamically selecting the hole for some of the "mapped" elements allows
  // using a static shape for the parameter map.
  int mapped_count = parameter_count;
  *has_aliased_arguments = true;

  // The unmapped argument values are stored yet another indirection away and
  // then linked into the parameter map below, whereas mapped argument values
  // (i.e. the first {mapped_count} elements) are replaced with a hole instead.
  Node* arguments =
1369
      graph()->NewNode(simplified()->NewArgumentsElements(mapped_count),
1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388
                       arguments_frame, arguments_length, effect);

  // Actually allocate the backing store.
  AllocationBuilder a(jsgraph(), arguments, control);
  a.AllocateArray(mapped_count + 2, factory()->sloppy_arguments_elements_map());
  a.Store(AccessBuilder::ForFixedArraySlot(0), context);
  a.Store(AccessBuilder::ForFixedArraySlot(1), arguments);
  for (int i = 0; i < mapped_count; ++i) {
    int idx = Context::MIN_CONTEXT_SLOTS + parameter_count - 1 - i;
    Node* value = graph()->NewNode(
        common()->Select(MachineRepresentation::kTagged),
        graph()->NewNode(simplified()->NumberLessThan(), jsgraph()->Constant(i),
                         arguments_length),
        jsgraph()->Constant(idx), jsgraph()->TheHoleConstant());
    a.Store(AccessBuilder::ForFixedArraySlot(i + 2), value);
  }
  return a.Finish();
}

1389 1390 1391 1392 1393 1394 1395
Node* JSCreateLowering::AllocateElements(Node* effect, Node* control,
                                         ElementsKind elements_kind,
                                         int capacity,
                                         PretenureFlag pretenure) {
  DCHECK_LE(1, capacity);
  DCHECK_LE(capacity, JSArray::kInitialMaxFastElementArray);

1396
  Handle<Map> elements_map = IsDoubleElementsKind(elements_kind)
1397 1398
                                 ? factory()->fixed_double_array_map()
                                 : factory()->fixed_array_map();
1399
  ElementAccess access = IsDoubleElementsKind(elements_kind)
1400 1401
                             ? AccessBuilder::ForFixedDoubleArrayElement()
                             : AccessBuilder::ForFixedArrayElement();
1402
  Node* value = jsgraph()->TheHoleConstant();
1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413

  // Actually allocate the backing store.
  AllocationBuilder a(jsgraph(), effect, control);
  a.AllocateArray(capacity, elements_map, pretenure);
  for (int i = 0; i < capacity; ++i) {
    Node* index = jsgraph()->Constant(i);
    a.Store(access, index, value);
  }
  return a.Finish();
}

1414 1415 1416 1417 1418 1419 1420 1421
Node* JSCreateLowering::AllocateElements(Node* effect, Node* control,
                                         ElementsKind elements_kind,
                                         std::vector<Node*> const& values,
                                         PretenureFlag pretenure) {
  int const capacity = static_cast<int>(values.size());
  DCHECK_LE(1, capacity);
  DCHECK_LE(capacity, JSArray::kInitialMaxFastElementArray);

1422
  Handle<Map> elements_map = IsDoubleElementsKind(elements_kind)
1423 1424
                                 ? factory()->fixed_double_array_map()
                                 : factory()->fixed_array_map();
1425
  ElementAccess access = IsDoubleElementsKind(elements_kind)
1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438
                             ? AccessBuilder::ForFixedDoubleArrayElement()
                             : AccessBuilder::ForFixedArrayElement();

  // Actually allocate the backing store.
  AllocationBuilder a(jsgraph(), effect, control);
  a.AllocateArray(capacity, elements_map, pretenure);
  for (int i = 0; i < capacity; ++i) {
    Node* index = jsgraph()->Constant(i);
    a.Store(access, index, values[i]);
  }
  return a.Finish();
}

1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465
Node* JSCreateLowering::AllocateFastLiteral(
    Node* effect, Node* control, Handle<JSObject> boilerplate,
    AllocationSiteUsageContext* site_context) {
  Handle<AllocationSite> current_site(*site_context->current(), isolate());
  dependencies()->AssumeTransitionStable(current_site);

  PretenureFlag pretenure = NOT_TENURED;
  if (FLAG_allocation_site_pretenuring) {
    Handle<AllocationSite> top_site(*site_context->top(), isolate());
    pretenure = top_site->GetPretenureMode();
    if (current_site.is_identical_to(top_site)) {
      // We install a dependency for pretenuring only on the outermost literal.
      dependencies()->AssumeTenuringDecision(top_site);
    }
  }

  // Setup the properties backing store.
  Node* properties = jsgraph()->EmptyFixedArrayConstant();

  // Compute the in-object properties to store first (might have effects).
  Handle<Map> boilerplate_map(boilerplate->map(), isolate());
  ZoneVector<std::pair<FieldAccess, Node*>> inobject_fields(zone());
  inobject_fields.reserve(boilerplate_map->GetInObjectProperties());
  int const boilerplate_nof = boilerplate_map->NumberOfOwnDescriptors();
  for (int i = 0; i < boilerplate_nof; ++i) {
    PropertyDetails const property_details =
        boilerplate_map->instance_descriptors()->GetDetails(i);
1466 1467
    if (property_details.location() != kField) continue;
    DCHECK_EQ(kData, property_details.kind());
1468 1469 1470
    Handle<Name> property_name(
        boilerplate_map->instance_descriptors()->GetKey(i), isolate());
    FieldIndex index = FieldIndex::ForDescriptor(*boilerplate_map, i);
1471 1472 1473 1474
    FieldAccess access = {kTaggedBase,      index.offset(),
                          property_name,    MaybeHandle<Map>(),
                          Type::Any(),      MachineType::AnyTagged(),
                          kFullWriteBarrier};
1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490
    Node* value;
    if (boilerplate->IsUnboxedDoubleField(index)) {
      access.machine_type = MachineType::Float64();
      access.type = Type::Number();
      value = jsgraph()->Constant(boilerplate->RawFastDoublePropertyAt(index));
    } else {
      Handle<Object> boilerplate_value(boilerplate->RawFastPropertyAt(index),
                                       isolate());
      if (boilerplate_value->IsJSObject()) {
        Handle<JSObject> boilerplate_object =
            Handle<JSObject>::cast(boilerplate_value);
        Handle<AllocationSite> current_site = site_context->EnterNewScope();
        value = effect = AllocateFastLiteral(effect, control,
                                             boilerplate_object, site_context);
        site_context->ExitScope(current_site, boilerplate_object);
      } else if (property_details.representation().IsDouble()) {
1491
        double number = Handle<HeapNumber>::cast(boilerplate_value)->value();
1492
        // Allocate a mutable HeapNumber box and store the value into it.
1493 1494 1495 1496 1497 1498 1499
        AllocationBuilder builder(jsgraph(), effect, control);
        builder.Allocate(HeapNumber::kSize, pretenure);
        builder.Store(AccessBuilder::ForMap(),
                      factory()->mutable_heap_number_map());
        builder.Store(AccessBuilder::ForHeapNumberValue(),
                      jsgraph()->Constant(number));
        value = effect = builder.Finish();
1500 1501
      } else if (property_details.representation().IsSmi()) {
        // Ensure that value is stored as smi.
1502
        value = boilerplate_value->IsUninitialized(isolate())
1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521
                    ? jsgraph()->ZeroConstant()
                    : jsgraph()->Constant(boilerplate_value);
      } else {
        value = jsgraph()->Constant(boilerplate_value);
      }
    }
    inobject_fields.push_back(std::make_pair(access, value));
  }

  // Fill slack at the end of the boilerplate object with filler maps.
  int const boilerplate_length = boilerplate_map->GetInObjectProperties();
  for (int index = static_cast<int>(inobject_fields.size());
       index < boilerplate_length; ++index) {
    FieldAccess access =
        AccessBuilder::ForJSObjectInObjectProperty(boilerplate_map, index);
    Node* value = jsgraph()->HeapConstant(factory()->one_pointer_filler_map());
    inobject_fields.push_back(std::make_pair(access, value));
  }

1522 1523 1524 1525 1526
  // Setup the elements backing store.
  Node* elements = AllocateFastLiteralElements(effect, control, boilerplate,
                                               pretenure, site_context);
  if (elements->op()->EffectOutputCount() > 0) effect = elements;

1527 1528
  // Actually allocate and initialize the object.
  AllocationBuilder builder(jsgraph(), effect, control);
1529
  builder.Allocate(boilerplate_map->instance_size(), pretenure,
1530
                   Type::For(boilerplate_map));
1531
  builder.Store(AccessBuilder::ForMap(), boilerplate_map);
1532
  builder.Store(AccessBuilder::ForJSObjectPropertiesOrHash(), properties);
1533 1534 1535 1536 1537 1538 1539
  builder.Store(AccessBuilder::ForJSObjectElements(), elements);
  if (boilerplate_map->IsJSArrayMap()) {
    Handle<JSArray> boilerplate_array = Handle<JSArray>::cast(boilerplate);
    builder.Store(
        AccessBuilder::ForJSArrayLength(boilerplate_array->GetElementsKind()),
        handle(boilerplate_array->length(), isolate()));
  }
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  for (auto const& inobject_field : inobject_fields) {
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    builder.Store(inobject_field.first, inobject_field.second);
  }
  return builder.Finish();
}

Node* JSCreateLowering::AllocateFastLiteralElements(
    Node* effect, Node* control, Handle<JSObject> boilerplate,
    PretenureFlag pretenure, AllocationSiteUsageContext* site_context) {
  Handle<FixedArrayBase> boilerplate_elements(boilerplate->elements(),
                                              isolate());

  // Empty or copy-on-write elements just store a constant.
  if (boilerplate_elements->length() == 0 ||
      boilerplate_elements->map() == isolate()->heap()->fixed_cow_array_map()) {
    if (pretenure == TENURED &&
        isolate()->heap()->InNewSpace(*boilerplate_elements)) {
      // If we would like to pretenure a fixed cow array, we must ensure that
      // the array is already in old space, otherwise we'll create too many
      // old-to-new-space pointers (overflowing the store buffer).
      boilerplate_elements = Handle<FixedArrayBase>(
          isolate()->factory()->CopyAndTenureFixedCOWArray(
              Handle<FixedArray>::cast(boilerplate_elements)));
      boilerplate->set_elements(*boilerplate_elements);
    }
    return jsgraph()->HeapConstant(boilerplate_elements);
  }

  // Compute the elements to store first (might have effects).
  int const elements_length = boilerplate_elements->length();
  Handle<Map> elements_map(boilerplate_elements->map(), isolate());
  ZoneVector<Node*> elements_values(elements_length, zone());
  if (elements_map->instance_type() == FIXED_DOUBLE_ARRAY_TYPE) {
    Handle<FixedDoubleArray> elements =
        Handle<FixedDoubleArray>::cast(boilerplate_elements);
    for (int i = 0; i < elements_length; ++i) {
      if (elements->is_the_hole(i)) {
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        elements_values[i] = jsgraph()->TheHoleConstant();
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      } else {
        elements_values[i] = jsgraph()->Constant(elements->get_scalar(i));
      }
    }
  } else {
    Handle<FixedArray> elements =
        Handle<FixedArray>::cast(boilerplate_elements);
    for (int i = 0; i < elements_length; ++i) {
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      if (elements->is_the_hole(isolate(), i)) {
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        elements_values[i] = jsgraph()->TheHoleConstant();
      } else {
        Handle<Object> element_value(elements->get(i), isolate());
        if (element_value->IsJSObject()) {
          Handle<JSObject> boilerplate_object =
              Handle<JSObject>::cast(element_value);
          Handle<AllocationSite> current_site = site_context->EnterNewScope();
          elements_values[i] = effect = AllocateFastLiteral(
              effect, control, boilerplate_object, site_context);
          site_context->ExitScope(current_site, boilerplate_object);
        } else {
          elements_values[i] = jsgraph()->Constant(element_value);
        }
      }
    }
  }

  // Allocate the backing store array and store the elements.
  AllocationBuilder builder(jsgraph(), effect, control);
  builder.AllocateArray(elements_length, elements_map, pretenure);
  ElementAccess const access =
      (elements_map->instance_type() == FIXED_DOUBLE_ARRAY_TYPE)
          ? AccessBuilder::ForFixedDoubleArrayElement()
          : AccessBuilder::ForFixedArrayElement();
  for (int i = 0; i < elements_length; ++i) {
    builder.Store(access, jsgraph()->Constant(i), elements_values[i]);
  }
  return builder.Finish();
}

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Node* JSCreateLowering::AllocateLiteralRegExp(Node* effect, Node* control,
                                              Handle<JSRegExp> boilerplate) {
  Handle<Map> boilerplate_map(boilerplate->map(), isolate());

  // Sanity check that JSRegExp object layout hasn't changed.
  STATIC_ASSERT(JSRegExp::kDataOffset == JSObject::kHeaderSize);
  STATIC_ASSERT(JSRegExp::kSourceOffset ==
                JSRegExp::kDataOffset + kPointerSize);
  STATIC_ASSERT(JSRegExp::kFlagsOffset ==
                JSRegExp::kSourceOffset + kPointerSize);
  STATIC_ASSERT(JSRegExp::kSize == JSRegExp::kFlagsOffset + kPointerSize);
  STATIC_ASSERT(JSRegExp::kLastIndexOffset == JSRegExp::kSize);
  STATIC_ASSERT(JSRegExp::kInObjectFieldCount == 1);  // LastIndex.

  const PretenureFlag pretenure = NOT_TENURED;
  const int size =
      JSRegExp::kSize + JSRegExp::kInObjectFieldCount * kPointerSize;

  AllocationBuilder builder(jsgraph(), effect, control);
  builder.Allocate(size, pretenure, Type::For(boilerplate_map));
  builder.Store(AccessBuilder::ForMap(), boilerplate_map);
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  builder.Store(AccessBuilder::ForJSObjectPropertiesOrHash(),
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                handle(boilerplate->raw_properties_or_hash(), isolate()));
  builder.Store(AccessBuilder::ForJSObjectElements(),
                handle(boilerplate->elements(), isolate()));

  builder.Store(AccessBuilder::ForJSRegExpData(),
                handle(boilerplate->data(), isolate()));
  builder.Store(AccessBuilder::ForJSRegExpSource(),
                handle(boilerplate->source(), isolate()));
  builder.Store(AccessBuilder::ForJSRegExpFlags(),
                handle(boilerplate->flags(), isolate()));
  builder.Store(AccessBuilder::ForJSRegExpLastIndex(),
                handle(boilerplate->last_index(), isolate()));

  return builder.Finish();
}

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Factory* JSCreateLowering::factory() const { return isolate()->factory(); }

Graph* JSCreateLowering::graph() const { return jsgraph()->graph(); }

Isolate* JSCreateLowering::isolate() const { return jsgraph()->isolate(); }

CommonOperatorBuilder* JSCreateLowering::common() const {
  return jsgraph()->common();
}

SimplifiedOperatorBuilder* JSCreateLowering::simplified() const {
  return jsgraph()->simplified();
}

}  // namespace compiler
}  // namespace internal
}  // namespace v8