src/compiler/bytecode-graph-builder.cc

// Copyright 2015 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/bytecode-graph-builder.h"

#include "src/ast/ast.h"
#include "src/ast/scopes.h"
#include "src/compiler/access-builder.h"
#include "src/compiler/compiler-source-position-table.h"
#include "src/compiler/linkage.h"
#include "src/compiler/operator-properties.h"
#include "src/compiler/simplified-operator.h"
#include "src/interpreter/bytecodes.h"
#include "src/objects-inl.h"
#include "src/objects/literal-objects.h"

namespace v8 {
namespace internal {
namespace compiler {

// The abstract execution environment simulates the content of the interpreter
// register file. The environment performs SSA-renaming of all tracked nodes at
// split and merge points in the control flow.
class BytecodeGraphBuilder::Environment : public ZoneObject {
 public:
  Environment(BytecodeGraphBuilder* builder, int register_count,
              int parameter_count, Node* control_dependency, Node* context);

  // Specifies whether environment binding methods should attach frame state
  // inputs to nodes representing the value being bound. This is done because
  // the {OutputFrameStateCombine} is closely related to the binding method.
  enum FrameStateAttachmentMode { kAttachFrameState, kDontAttachFrameState };

  int parameter_count() const { return parameter_count_; }
  int register_count() const { return register_count_; }

  Node* LookupAccumulator() const;
  Node* LookupRegister(interpreter::Register the_register) const;

  void BindAccumulator(Node* node,
                       FrameStateAttachmentMode mode = kDontAttachFrameState);
  void BindRegister(interpreter::Register the_register, Node* node,
                    FrameStateAttachmentMode mode = kDontAttachFrameState);
  void BindRegistersToProjections(
      interpreter::Register first_reg, Node* node,
      FrameStateAttachmentMode mode = kDontAttachFrameState);
  void RecordAfterState(Node* node,
                        FrameStateAttachmentMode mode = kDontAttachFrameState);

  // Effect dependency tracked by this environment.
  Node* GetEffectDependency() { return effect_dependency_; }
  void UpdateEffectDependency(Node* dependency) {
    effect_dependency_ = dependency;
  }

  // Preserve a checkpoint of the environment for the IR graph. Any
  // further mutation of the environment will not affect checkpoints.
  Node* Checkpoint(BailoutId bytecode_offset, OutputFrameStateCombine combine,
                   const BytecodeLivenessState* liveness);

  // Control dependency tracked by this environment.
  Node* GetControlDependency() const { return control_dependency_; }
  void UpdateControlDependency(Node* dependency) {
    control_dependency_ = dependency;
  }

  Node* Context() const { return context_; }
  void SetContext(Node* new_context) { context_ = new_context; }

  Environment* Copy();
  void Merge(Environment* other);

  void PrepareForOsrEntry();
  void PrepareForLoop(const BytecodeLoopAssignments& assignments);
  void PrepareForLoopExit(Node* loop,
                          const BytecodeLoopAssignments& assignments);

 private:
  explicit Environment(const Environment* copy);

  bool StateValuesRequireUpdate(Node** state_values, Node** values, int count);
  void UpdateStateValues(Node** state_values, Node** values, int count);
  Node* GetStateValuesFromCache(Node** values, int count,
                                const BitVector* liveness, int liveness_offset);

  int RegisterToValuesIndex(interpreter::Register the_register) const;

  Zone* zone() const { return builder_->local_zone(); }
  Graph* graph() const { return builder_->graph(); }
  CommonOperatorBuilder* common() const { return builder_->common(); }
  BytecodeGraphBuilder* builder() const { return builder_; }
  const NodeVector* values() const { return &values_; }
  NodeVector* values() { return &values_; }
  int register_base() const { return register_base_; }
  int accumulator_base() const { return accumulator_base_; }

  BytecodeGraphBuilder* builder_;
  int register_count_;
  int parameter_count_;
  Node* context_;
  Node* control_dependency_;
  Node* effect_dependency_;
  NodeVector values_;
  Node* parameters_state_values_;
  int register_base_;
  int accumulator_base_;
};

// A helper for creating a temporary sub-environment for simple branches.
struct BytecodeGraphBuilder::SubEnvironment final {
 public:
  explicit SubEnvironment(BytecodeGraphBuilder* builder)
      : builder_(builder), parent_(builder->environment()->Copy()) {}

  ~SubEnvironment() { builder_->set_environment(parent_); }

 private:
  BytecodeGraphBuilder* builder_;
  BytecodeGraphBuilder::Environment* parent_;
};

// Issues:
// - Scopes - intimately tied to AST. Need to eval what is needed.
// - Need to resolve closure parameter treatment.
BytecodeGraphBuilder::Environment::Environment(BytecodeGraphBuilder* builder,
                                               int register_count,
                                               int parameter_count,
                                               Node* control_dependency,
                                               Node* context)
    : builder_(builder),
      register_count_(register_count),
      parameter_count_(parameter_count),
      context_(context),
      control_dependency_(control_dependency),
      effect_dependency_(control_dependency),
      values_(builder->local_zone()),
      parameters_state_values_(nullptr) {
  // The layout of values_ is:
  //
  // [receiver] [parameters] [registers] [accumulator]
  //
  // parameter[0] is the receiver (this), parameters 1..N are the
  // parameters supplied to the method (arg0..argN-1). The accumulator
  // is stored separately.

  // Parameters including the receiver
  for (int i = 0; i < parameter_count; i++) {
    const char* debug_name = (i == 0) ? "%this" : nullptr;
    const Operator* op = common()->Parameter(i, debug_name);
    Node* parameter = builder->graph()->NewNode(op, graph()->start());
    values()->push_back(parameter);
  }

  // Registers
  register_base_ = static_cast<int>(values()->size());
  Node* undefined_constant = builder->jsgraph()->UndefinedConstant();
  values()->insert(values()->end(), register_count, undefined_constant);

  // Accumulator
  accumulator_base_ = static_cast<int>(values()->size());
  values()->push_back(undefined_constant);
}

BytecodeGraphBuilder::Environment::Environment(
    const BytecodeGraphBuilder::Environment* other)
    : builder_(other->builder_),
      register_count_(other->register_count_),
      parameter_count_(other->parameter_count_),
      context_(other->context_),
      control_dependency_(other->control_dependency_),
      effect_dependency_(other->effect_dependency_),
      values_(other->zone()),
      parameters_state_values_(other->parameters_state_values_),
      register_base_(other->register_base_),
      accumulator_base_(other->accumulator_base_) {
  values_ = other->values_;
}


int BytecodeGraphBuilder::Environment::RegisterToValuesIndex(
    interpreter::Register the_register) const {
  if (the_register.is_parameter()) {
    return the_register.ToParameterIndex(parameter_count());
  } else {
    return the_register.index() + register_base();
  }
}

Node* BytecodeGraphBuilder::Environment::LookupAccumulator() const {
  return values()->at(accumulator_base_);
}


Node* BytecodeGraphBuilder::Environment::LookupRegister(
    interpreter::Register the_register) const {
  if (the_register.is_current_context()) {
    return Context();
  } else if (the_register.is_function_closure()) {
    return builder()->GetFunctionClosure();
  } else if (the_register.is_new_target()) {
    return builder()->GetNewTarget();
  } else {
    int values_index = RegisterToValuesIndex(the_register);
    return values()->at(values_index);
  }
}

void BytecodeGraphBuilder::Environment::BindAccumulator(
    Node* node, FrameStateAttachmentMode mode) {
  if (mode == FrameStateAttachmentMode::kAttachFrameState) {
    builder()->PrepareFrameState(node, OutputFrameStateCombine::PokeAt(0));
  }
  values()->at(accumulator_base_) = node;
}

void BytecodeGraphBuilder::Environment::BindRegister(
    interpreter::Register the_register, Node* node,
    FrameStateAttachmentMode mode) {
  int values_index = RegisterToValuesIndex(the_register);
  if (mode == FrameStateAttachmentMode::kAttachFrameState) {
    builder()->PrepareFrameState(node, OutputFrameStateCombine::PokeAt(
                                           accumulator_base_ - values_index));
  }
  values()->at(values_index) = node;
}

void BytecodeGraphBuilder::Environment::BindRegistersToProjections(
    interpreter::Register first_reg, Node* node,
    FrameStateAttachmentMode mode) {
  int values_index = RegisterToValuesIndex(first_reg);
  if (mode == FrameStateAttachmentMode::kAttachFrameState) {
    builder()->PrepareFrameState(node, OutputFrameStateCombine::PokeAt(
                                           accumulator_base_ - values_index));
  }
  for (int i = 0; i < node->op()->ValueOutputCount(); i++) {
    values()->at(values_index + i) =
        builder()->NewNode(common()->Projection(i), node);
  }
}

void BytecodeGraphBuilder::Environment::RecordAfterState(
    Node* node, FrameStateAttachmentMode mode) {
  if (mode == FrameStateAttachmentMode::kAttachFrameState) {
    builder()->PrepareFrameState(node, OutputFrameStateCombine::Ignore());
  }
}

BytecodeGraphBuilder::Environment* BytecodeGraphBuilder::Environment::Copy() {
  return new (zone()) Environment(this);
}


void BytecodeGraphBuilder::Environment::Merge(
    BytecodeGraphBuilder::Environment* other) {
  // Create a merge of the control dependencies of both environments and update
  // the current environment's control dependency accordingly.
  Node* control = builder()->MergeControl(GetControlDependency(),
                                          other->GetControlDependency());
  UpdateControlDependency(control);

  // Create a merge of the effect dependencies of both environments and update
  // the current environment's effect dependency accordingly.
  Node* effect = builder()->MergeEffect(GetEffectDependency(),
                                        other->GetEffectDependency(), control);
  UpdateEffectDependency(effect);

  // Introduce Phi nodes for values that have differing input at merge points,
  // potentially extending an existing Phi node if possible.
  context_ = builder()->MergeValue(context_, other->context_, control);
  for (size_t i = 0; i < values_.size(); i++) {
    values_[i] = builder()->MergeValue(values_[i], other->values_[i], control);
  }
}

void BytecodeGraphBuilder::Environment::PrepareForLoop(
    const BytecodeLoopAssignments& assignments) {
  // Create a control node for the loop header.
  Node* control = builder()->NewLoop();

  // Create a Phi for external effects.
  Node* effect = builder()->NewEffectPhi(1, GetEffectDependency(), control);
  UpdateEffectDependency(effect);

  // Create Phis for any values that may be updated by the end of the loop.
  context_ = builder()->NewPhi(1, context_, control);
  for (int i = 0; i < parameter_count(); i++) {
    if (assignments.ContainsParameter(i)) {
      values_[i] = builder()->NewPhi(1, values_[i], control);
    }
  }
  for (int i = 0; i < register_count(); i++) {
    if (assignments.ContainsLocal(i)) {
      int index = register_base() + i;
      values_[index] = builder()->NewPhi(1, values_[index], control);
    }
  }

  if (assignments.ContainsAccumulator()) {
    values_[accumulator_base()] =
        builder()->NewPhi(1, values_[accumulator_base()], control);
  }

  // Connect to the loop end.
  Node* terminate = builder()->graph()->NewNode(
      builder()->common()->Terminate(), effect, control);
  builder()->exit_controls_.push_back(terminate);
}

void BytecodeGraphBuilder::Environment::PrepareForOsrEntry() {
  DCHECK_EQ(IrOpcode::kLoop, GetControlDependency()->opcode());
  DCHECK_EQ(1, GetControlDependency()->InputCount());

  Node* start = graph()->start();

  // Create a control node for the OSR entry point and update the current
  // environment's dependencies accordingly.
  Node* entry = graph()->NewNode(common()->OsrLoopEntry(), start, start);
  UpdateControlDependency(entry);
  UpdateEffectDependency(entry);

  // Create OSR values for each environment value.
  SetContext(graph()->NewNode(
      common()->OsrValue(Linkage::kOsrContextSpillSlotIndex), entry));
  int size = static_cast<int>(values()->size());
  for (int i = 0; i < size; i++) {
    int idx = i;  // Indexing scheme follows {StandardFrame}, adapt accordingly.
    if (i >= register_base()) idx += InterpreterFrameConstants::kExtraSlotCount;
    if (i >= accumulator_base()) idx = Linkage::kOsrAccumulatorRegisterIndex;
    values()->at(i) = graph()->NewNode(common()->OsrValue(idx), entry);
  }
}

bool BytecodeGraphBuilder::Environment::StateValuesRequireUpdate(
    Node** state_values, Node** values, int count) {
  if (*state_values == nullptr) {
    return true;
  }
  Node::Inputs inputs = (*state_values)->inputs();
  if (inputs.count() != count) return true;
  for (int i = 0; i < count; i++) {
    if (inputs[i] != values[i]) {
      return true;
    }
  }
  return false;
}

void BytecodeGraphBuilder::Environment::PrepareForLoopExit(
    Node* loop, const BytecodeLoopAssignments& assignments) {
  DCHECK_EQ(loop->opcode(), IrOpcode::kLoop);

  Node* control = GetControlDependency();

  // Create the loop exit node.
  Node* loop_exit = graph()->NewNode(common()->LoopExit(), control, loop);
  UpdateControlDependency(loop_exit);

  // Rename the effect.
  Node* effect_rename = graph()->NewNode(common()->LoopExitEffect(),
                                         GetEffectDependency(), loop_exit);
  UpdateEffectDependency(effect_rename);

  // TODO(jarin) We should also rename context here. However, unconditional
  // renaming confuses global object and native context specialization.
  // We should only rename if the context is assigned in the loop.

  // Rename the environment values if they were assigned in the loop.
  for (int i = 0; i < parameter_count(); i++) {
    if (assignments.ContainsParameter(i)) {
      Node* rename =
          graph()->NewNode(common()->LoopExitValue(), values_[i], loop_exit);
      values_[i] = rename;
    }
  }
  for (int i = 0; i < register_count(); i++) {
    if (assignments.ContainsLocal(i)) {
      Node* rename = graph()->NewNode(common()->LoopExitValue(),
                                      values_[register_base() + i], loop_exit);
      values_[register_base() + i] = rename;
    }
  }

  if (assignments.ContainsAccumulator()) {
    Node* rename = graph()->NewNode(common()->LoopExitValue(),
                                    values_[accumulator_base()], loop_exit);
    values_[accumulator_base()] = rename;
  }
}

void BytecodeGraphBuilder::Environment::UpdateStateValues(Node** state_values,
                                                          Node** values,
                                                          int count) {
  if (StateValuesRequireUpdate(state_values, values, count)) {
    const Operator* op = common()->StateValues(count, SparseInputMask::Dense());
    (*state_values) = graph()->NewNode(op, count, values);
  }
}

Node* BytecodeGraphBuilder::Environment::GetStateValuesFromCache(
    Node** values, int count, const BitVector* liveness, int liveness_offset) {
  return builder_->state_values_cache_.GetNodeForValues(
      values, static_cast<size_t>(count), liveness, liveness_offset);
}

Node* BytecodeGraphBuilder::Environment::Checkpoint(
    BailoutId bailout_id, OutputFrameStateCombine combine,
    const BytecodeLivenessState* liveness) {
  if (parameter_count() == register_count()) {
    // Re-use the state-value cache if the number of local registers happens
    // to match the parameter count.
    parameters_state_values_ = GetStateValuesFromCache(
        &values()->at(0), parameter_count(), nullptr, 0);
  } else {
    UpdateStateValues(&parameters_state_values_, &values()->at(0),
                      parameter_count());
  }

  Node* registers_state_values =
      GetStateValuesFromCache(&values()->at(register_base()), register_count(),
                              liveness ? &liveness->bit_vector() : nullptr, 0);

  bool accumulator_is_live = !liveness || liveness->AccumulatorIsLive();
  Node* accumulator_state_value =
      accumulator_is_live ? values()->at(accumulator_base())
                          : builder()->jsgraph()->OptimizedOutConstant();

  const Operator* op = common()->FrameState(
      bailout_id, combine, builder()->frame_state_function_info());
  Node* result = graph()->NewNode(
      op, parameters_state_values_, registers_state_values,
      accumulator_state_value, Context(), builder()->GetFunctionClosure(),
      builder()->graph()->start());

  return result;
}

BytecodeGraphBuilder::BytecodeGraphBuilder(
    Zone* local_zone, Handle<SharedFunctionInfo> shared_info,
    Handle<FeedbackVector> feedback_vector, BailoutId osr_ast_id,
    JSGraph* jsgraph, CallFrequency invocation_frequency,
    SourcePositionTable* source_positions, int inlining_id,
    JSTypeHintLowering::Flags flags)
    : local_zone_(local_zone),
      jsgraph_(jsgraph),
      invocation_frequency_(invocation_frequency),
      bytecode_array_(handle(shared_info->bytecode_array())),
      exception_handler_table_(
          handle(HandlerTable::cast(bytecode_array()->handler_table()))),
      feedback_vector_(feedback_vector),
      type_hint_lowering_(jsgraph, feedback_vector, flags),
      frame_state_function_info_(common()->CreateFrameStateFunctionInfo(
          FrameStateType::kInterpretedFunction,
          bytecode_array()->parameter_count(),
          bytecode_array()->register_count(), shared_info)),
      bytecode_iterator_(nullptr),
      bytecode_analysis_(nullptr),
      environment_(nullptr),
      osr_ast_id_(osr_ast_id),
      merge_environments_(local_zone),
      exception_handlers_(local_zone),
      current_exception_handler_(0),
      input_buffer_size_(0),
      input_buffer_(nullptr),
      needs_eager_checkpoint_(true),
      exit_controls_(local_zone),
      state_values_cache_(jsgraph),
      source_positions_(source_positions),
      start_position_(shared_info->start_position(), inlining_id) {}

Node* BytecodeGraphBuilder::GetNewTarget() {
  if (!new_target_.is_set()) {
    int params = bytecode_array()->parameter_count();
    int index = Linkage::GetJSCallNewTargetParamIndex(params);
    const Operator* op = common()->Parameter(index, "%new.target");
    Node* node = NewNode(op, graph()->start());
    new_target_.set(node);
  }
  return new_target_.get();
}


Node* BytecodeGraphBuilder::GetFunctionContext() {
  if (!function_context_.is_set()) {
    int params = bytecode_array()->parameter_count();
    int index = Linkage::GetJSCallContextParamIndex(params);
    const Operator* op = common()->Parameter(index, "%context");
    Node* node = NewNode(op, graph()->start());
    function_context_.set(node);
  }
  return function_context_.get();
}


Node* BytecodeGraphBuilder::GetFunctionClosure() {
  if (!function_closure_.is_set()) {
    int index = Linkage::kJSCallClosureParamIndex;
    const Operator* op = common()->Parameter(index, "%closure");
    Node* node = NewNode(op, graph()->start());
    function_closure_.set(node);
  }
  return function_closure_.get();
}


Node* BytecodeGraphBuilder::BuildLoadNativeContextField(int index) {
  const Operator* op =
      javascript()->LoadContext(0, Context::NATIVE_CONTEXT_INDEX, true);
  Node* native_context = NewNode(op);
  Node* result = NewNode(javascript()->LoadContext(0, index, true));
  NodeProperties::ReplaceContextInput(result, native_context);
  return result;
}


VectorSlotPair BytecodeGraphBuilder::CreateVectorSlotPair(int slot_id) {
  FeedbackSlot slot;
  if (slot_id >= FeedbackVector::kReservedIndexCount) {
    slot = feedback_vector()->ToSlot(slot_id);
  }
  return VectorSlotPair(feedback_vector(), slot);
}

void BytecodeGraphBuilder::CreateGraph(bool stack_check) {
  SourcePositionTable::Scope pos_scope(source_positions_, start_position_);

  // Set up the basic structure of the graph. Outputs for {Start} are the formal
  // parameters (including the receiver) plus new target, number of arguments,
  // context and closure.
  int actual_parameter_count = bytecode_array()->parameter_count() + 4;
  graph()->SetStart(graph()->NewNode(common()->Start(actual_parameter_count)));

  Environment env(this, bytecode_array()->register_count(),
                  bytecode_array()->parameter_count(), graph()->start(),
                  GetFunctionContext());
  set_environment(&env);

  VisitBytecodes(stack_check);

  // Finish the basic structure of the graph.
  DCHECK_NE(0u, exit_controls_.size());
  int const input_count = static_cast<int>(exit_controls_.size());
  Node** const inputs = &exit_controls_.front();
  Node* end = graph()->NewNode(common()->End(input_count), input_count, inputs);
  graph()->SetEnd(end);
}

void BytecodeGraphBuilder::PrepareEagerCheckpoint() {
  if (needs_eager_checkpoint()) {
    // Create an explicit checkpoint node for before the operation. This only
    // needs to happen if we aren't effect-dominated by a {Checkpoint} already.
    mark_as_needing_eager_checkpoint(false);
    Node* node = NewNode(common()->Checkpoint());
    DCHECK_EQ(1, OperatorProperties::GetFrameStateInputCount(node->op()));
    DCHECK_EQ(IrOpcode::kDead,
              NodeProperties::GetFrameStateInput(node)->opcode());
    BailoutId bailout_id(bytecode_iterator().current_offset());

    const BytecodeLivenessState* liveness_before =
        bytecode_analysis()->GetInLivenessFor(
            bytecode_iterator().current_offset());

    Node* frame_state_before = environment()->Checkpoint(
        bailout_id, OutputFrameStateCombine::Ignore(), liveness_before);
    NodeProperties::ReplaceFrameStateInput(node, frame_state_before);
#ifdef DEBUG
  } else {
    // In case we skipped checkpoint creation above, we must be able to find an
    // existing checkpoint that effect-dominates the nodes about to be created.
    // Starting a search from the current effect-dependency has to succeed.
    Node* effect = environment()->GetEffectDependency();
    while (effect->opcode() != IrOpcode::kCheckpoint) {
      DCHECK(effect->op()->HasProperty(Operator::kNoWrite));
      DCHECK_EQ(1, effect->op()->EffectInputCount());
      effect = NodeProperties::GetEffectInput(effect);
    }
  }
#else
  }
#endif  // DEBUG
}

void BytecodeGraphBuilder::PrepareFrameState(Node* node,
                                             OutputFrameStateCombine combine) {
  if (OperatorProperties::HasFrameStateInput(node->op())) {
    // Add the frame state for after the operation. The node in question has
    // already been created and had a {Dead} frame state input up until now.
    DCHECK_EQ(1, OperatorProperties::GetFrameStateInputCount(node->op()));
    DCHECK_EQ(IrOpcode::kDead,
              NodeProperties::GetFrameStateInput(node)->opcode());
    BailoutId bailout_id(bytecode_iterator().current_offset());

    const BytecodeLivenessState* liveness_after =
        bytecode_analysis()->GetOutLivenessFor(
            bytecode_iterator().current_offset());

    Node* frame_state_after =
        environment()->Checkpoint(bailout_id, combine, liveness_after);
    NodeProperties::ReplaceFrameStateInput(node, frame_state_after);
  }
}

void BytecodeGraphBuilder::VisitBytecodes(bool stack_check) {
  BytecodeAnalysis bytecode_analysis(bytecode_array(), local_zone(),
                                     FLAG_analyze_environment_liveness);
  bytecode_analysis.Analyze(osr_ast_id_);
  set_bytecode_analysis(&bytecode_analysis);

  interpreter::BytecodeArrayIterator iterator(bytecode_array());
  set_bytecode_iterator(&iterator);
  SourcePositionTableIterator source_position_iterator(
      handle(bytecode_array()->SourcePositionTable()));

  if (FLAG_trace_environment_liveness) {
    OFStream of(stdout);

    bytecode_analysis.PrintLivenessTo(of);
  }

  BuildOSRNormalEntryPoint();

  for (; !iterator.done(); iterator.Advance()) {
    int current_offset = iterator.current_offset();
    UpdateCurrentSourcePosition(&source_position_iterator, current_offset);
    EnterAndExitExceptionHandlers(current_offset);
    SwitchToMergeEnvironment(current_offset);
    if (environment() != nullptr) {
      BuildLoopHeaderEnvironment(current_offset);

      // Skip the first stack check if stack_check is false
      if (!stack_check &&
          iterator.current_bytecode() == interpreter::Bytecode::kStackCheck) {
        stack_check = true;
        continue;
      }

      switch (iterator.current_bytecode()) {
#define BYTECODE_CASE(name, ...)       \
  case interpreter::Bytecode::k##name: \
    Visit##name();                     \
    break;
        BYTECODE_LIST(BYTECODE_CASE)
#undef BYTECODE_CODE
      }
    }
  }
  set_bytecode_analysis(nullptr);
  set_bytecode_iterator(nullptr);
  DCHECK(exception_handlers_.empty());
}

void BytecodeGraphBuilder::VisitLdaZero() {
  Node* node = jsgraph()->ZeroConstant();
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaSmi() {
  Node* node = jsgraph()->Constant(bytecode_iterator().GetImmediateOperand(0));
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaConstant() {
  Node* node =
      jsgraph()->Constant(bytecode_iterator().GetConstantForIndexOperand(0));
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaUndefined() {
  Node* node = jsgraph()->UndefinedConstant();
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaNull() {
  Node* node = jsgraph()->NullConstant();
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaTheHole() {
  Node* node = jsgraph()->TheHoleConstant();
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaTrue() {
  Node* node = jsgraph()->TrueConstant();
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaFalse() {
  Node* node = jsgraph()->FalseConstant();
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdar() {
  Node* value =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  environment()->BindAccumulator(value);
}

void BytecodeGraphBuilder::VisitStar() {
  Node* value = environment()->LookupAccumulator();
  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(0), value);
}

void BytecodeGraphBuilder::VisitMov() {
  Node* value =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(1), value);
}

Node* BytecodeGraphBuilder::BuildLoadGlobal(Handle<Name> name,
                                            uint32_t feedback_slot_index,
                                            TypeofMode typeof_mode) {
  VectorSlotPair feedback = CreateVectorSlotPair(feedback_slot_index);
  DCHECK(IsLoadGlobalICKind(feedback_vector()->GetKind(feedback.slot())));
  const Operator* op = javascript()->LoadGlobal(name, feedback, typeof_mode);
  return NewNode(op);
}

void BytecodeGraphBuilder::VisitLdaGlobal() {
  PrepareEagerCheckpoint();
  Handle<Name> name =
      Handle<Name>::cast(bytecode_iterator().GetConstantForIndexOperand(0));
  uint32_t feedback_slot_index = bytecode_iterator().GetIndexOperand(1);
  Node* node =
      BuildLoadGlobal(name, feedback_slot_index, TypeofMode::NOT_INSIDE_TYPEOF);
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitLdaGlobalInsideTypeof() {
  PrepareEagerCheckpoint();
  Handle<Name> name =
      Handle<Name>::cast(bytecode_iterator().GetConstantForIndexOperand(0));
  uint32_t feedback_slot_index = bytecode_iterator().GetIndexOperand(1);
  Node* node =
      BuildLoadGlobal(name, feedback_slot_index, TypeofMode::INSIDE_TYPEOF);
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::BuildStoreGlobal(LanguageMode language_mode) {
  PrepareEagerCheckpoint();
  Handle<Name> name =
      Handle<Name>::cast(bytecode_iterator().GetConstantForIndexOperand(0));
  VectorSlotPair feedback =
      CreateVectorSlotPair(bytecode_iterator().GetIndexOperand(1));
  Node* value = environment()->LookupAccumulator();

  const Operator* op = javascript()->StoreGlobal(language_mode, name, feedback);
  Node* node = NewNode(op, value);
  environment()->RecordAfterState(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitStaGlobalSloppy() {
  BuildStoreGlobal(LanguageMode::SLOPPY);
}

void BytecodeGraphBuilder::VisitStaGlobalStrict() {
  BuildStoreGlobal(LanguageMode::STRICT);
}

void BytecodeGraphBuilder::VisitStaDataPropertyInLiteral() {
  PrepareEagerCheckpoint();

  Node* object =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* name =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  Node* value = environment()->LookupAccumulator();
  int flags = bytecode_iterator().GetFlagOperand(2);
  VectorSlotPair feedback =
      CreateVectorSlotPair(bytecode_iterator().GetIndexOperand(3));

  const Operator* op = javascript()->StoreDataPropertyInLiteral(feedback);
  Node* node = NewNode(op, object, name, value, jsgraph()->Constant(flags));
  environment()->RecordAfterState(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitCollectTypeProfile() {
  PrepareEagerCheckpoint();

  Node* position =
      jsgraph()->Constant(bytecode_iterator().GetImmediateOperand(0));
  Node* value = environment()->LookupAccumulator();
  Node* vector = jsgraph()->Constant(feedback_vector());

  const Operator* op = javascript()->CallRuntime(Runtime::kCollectTypeProfile);

  Node* node = NewNode(op, position, value, vector);
  environment()->RecordAfterState(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitLdaContextSlot() {
  const Operator* op = javascript()->LoadContext(
      bytecode_iterator().GetUnsignedImmediateOperand(2),
      bytecode_iterator().GetIndexOperand(1), false);
  Node* node = NewNode(op);
  Node* context =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  NodeProperties::ReplaceContextInput(node, context);
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaImmutableContextSlot() {
  const Operator* op = javascript()->LoadContext(
      bytecode_iterator().GetUnsignedImmediateOperand(2),
      bytecode_iterator().GetIndexOperand(1), true);
  Node* node = NewNode(op);
  Node* context =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  NodeProperties::ReplaceContextInput(node, context);
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaCurrentContextSlot() {
  const Operator* op = javascript()->LoadContext(
      0, bytecode_iterator().GetIndexOperand(0), false);
  Node* node = NewNode(op);
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitLdaImmutableCurrentContextSlot() {
  const Operator* op = javascript()->LoadContext(
      0, bytecode_iterator().GetIndexOperand(0), true);
  Node* node = NewNode(op);
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitStaContextSlot() {
  const Operator* op = javascript()->StoreContext(
      bytecode_iterator().GetUnsignedImmediateOperand(2),
      bytecode_iterator().GetIndexOperand(1));
  Node* value = environment()->LookupAccumulator();
  Node* node = NewNode(op, value);
  Node* context =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  NodeProperties::ReplaceContextInput(node, context);
}

void BytecodeGraphBuilder::VisitStaCurrentContextSlot() {
  const Operator* op =
      javascript()->StoreContext(0, bytecode_iterator().GetIndexOperand(0));
  Node* value = environment()->LookupAccumulator();
  NewNode(op, value);
}

void BytecodeGraphBuilder::BuildLdaLookupSlot(TypeofMode typeof_mode) {
  PrepareEagerCheckpoint();
  Node* name =
      jsgraph()->Constant(bytecode_iterator().GetConstantForIndexOperand(0));
  const Operator* op =
      javascript()->CallRuntime(typeof_mode == TypeofMode::NOT_INSIDE_TYPEOF
                                    ? Runtime::kLoadLookupSlot
                                    : Runtime::kLoadLookupSlotInsideTypeof);
  Node* value = NewNode(op, name);
  environment()->BindAccumulator(value, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitLdaLookupSlot() {
  BuildLdaLookupSlot(TypeofMode::NOT_INSIDE_TYPEOF);
}

void BytecodeGraphBuilder::VisitLdaLookupSlotInsideTypeof() {
  BuildLdaLookupSlot(TypeofMode::INSIDE_TYPEOF);
}

BytecodeGraphBuilder::Environment* BytecodeGraphBuilder::CheckContextExtensions(
    uint32_t depth) {
  // Output environment where the context has an extension
  Environment* slow_environment = nullptr;

  // We only need to check up to the last-but-one depth, because the an eval in
  // the same scope as the variable itself has no way of shadowing it.
  for (uint32_t d = 0; d < depth; d++) {
    Node* extension_slot =
        NewNode(javascript()->LoadContext(d, Context::EXTENSION_INDEX, false));

    Node* check_no_extension =
        NewNode(simplified()->ReferenceEqual(), extension_slot,
                jsgraph()->TheHoleConstant());

    NewBranch(check_no_extension);

    {
      SubEnvironment sub_environment(this);

      NewIfFalse();
      // If there is an extension, merge into the slow path.
      if (slow_environment == nullptr) {
        slow_environment = environment();
        NewMerge();
      } else {
        slow_environment->Merge(environment());
      }
    }

    NewIfTrue();
    // Do nothing on if there is no extension, eventually falling through to
    // the fast path.
  }

  // The depth can be zero, in which case no slow-path checks are built, and the
  // slow path environment can be null.
  DCHECK(depth == 0 || slow_environment != nullptr);

  return slow_environment;
}

void BytecodeGraphBuilder::BuildLdaLookupContextSlot(TypeofMode typeof_mode) {
  uint32_t depth = bytecode_iterator().GetUnsignedImmediateOperand(2);

  // Check if any context in the depth has an extension.
  Environment* slow_environment = CheckContextExtensions(depth);

  // Fast path, do a context load.
  {
    uint32_t slot_index = bytecode_iterator().GetIndexOperand(1);

    const Operator* op = javascript()->LoadContext(depth, slot_index, false);
    environment()->BindAccumulator(NewNode(op));
  }

  // Only build the slow path if there were any slow-path checks.
  if (slow_environment != nullptr) {
    // Add a merge to the fast environment.
    NewMerge();
    Environment* fast_environment = environment();

    // Slow path, do a runtime load lookup.
    set_environment(slow_environment);
    {
      Node* name = jsgraph()->Constant(
          bytecode_iterator().GetConstantForIndexOperand(0));

      const Operator* op =
          javascript()->CallRuntime(typeof_mode == TypeofMode::NOT_INSIDE_TYPEOF
                                        ? Runtime::kLoadLookupSlot
                                        : Runtime::kLoadLookupSlotInsideTypeof);
      Node* value = NewNode(op, name);
      environment()->BindAccumulator(value, Environment::kAttachFrameState);
    }

    fast_environment->Merge(environment());
    set_environment(fast_environment);
    mark_as_needing_eager_checkpoint(true);
  }
}

void BytecodeGraphBuilder::VisitLdaLookupContextSlot() {
  BuildLdaLookupContextSlot(TypeofMode::NOT_INSIDE_TYPEOF);
}

void BytecodeGraphBuilder::VisitLdaLookupContextSlotInsideTypeof() {
  BuildLdaLookupContextSlot(TypeofMode::INSIDE_TYPEOF);
}

void BytecodeGraphBuilder::BuildLdaLookupGlobalSlot(TypeofMode typeof_mode) {
  uint32_t depth = bytecode_iterator().GetUnsignedImmediateOperand(2);

  // Check if any context in the depth has an extension.
  Environment* slow_environment = CheckContextExtensions(depth);

  // Fast path, do a global load.
  {
    PrepareEagerCheckpoint();
    Handle<Name> name =
        Handle<Name>::cast(bytecode_iterator().GetConstantForIndexOperand(0));
    uint32_t feedback_slot_index = bytecode_iterator().GetIndexOperand(1);
    Node* node = BuildLoadGlobal(name, feedback_slot_index, typeof_mode);
    environment()->BindAccumulator(node, Environment::kAttachFrameState);
  }

  // Only build the slow path if there were any slow-path checks.
  if (slow_environment != nullptr) {
    // Add a merge to the fast environment.
    NewMerge();
    Environment* fast_environment = environment();

    // Slow path, do a runtime load lookup.
    set_environment(slow_environment);
    {
      Node* name = jsgraph()->Constant(
          bytecode_iterator().GetConstantForIndexOperand(0));

      const Operator* op =
          javascript()->CallRuntime(typeof_mode == TypeofMode::NOT_INSIDE_TYPEOF
                                        ? Runtime::kLoadLookupSlot
                                        : Runtime::kLoadLookupSlotInsideTypeof);
      Node* value = NewNode(op, name);
      environment()->BindAccumulator(value, Environment::kAttachFrameState);
    }

    fast_environment->Merge(environment());
    set_environment(fast_environment);
    mark_as_needing_eager_checkpoint(true);
  }
}

void BytecodeGraphBuilder::VisitLdaLookupGlobalSlot() {
  BuildLdaLookupGlobalSlot(TypeofMode::NOT_INSIDE_TYPEOF);
}

void BytecodeGraphBuilder::VisitLdaLookupGlobalSlotInsideTypeof() {
  BuildLdaLookupGlobalSlot(TypeofMode::INSIDE_TYPEOF);
}

void BytecodeGraphBuilder::VisitStaLookupSlot() {
  PrepareEagerCheckpoint();
  Node* value = environment()->LookupAccumulator();
  Node* name =
      jsgraph()->Constant(bytecode_iterator().GetConstantForIndexOperand(0));
  int bytecode_flags = bytecode_iterator().GetFlagOperand(1);
  LanguageMode language_mode = static_cast<LanguageMode>(
      interpreter::StoreLookupSlotFlags::LanguageModeBit::decode(
          bytecode_flags));
  LookupHoistingMode lookup_hoisting_mode = static_cast<LookupHoistingMode>(
      interpreter::StoreLookupSlotFlags::LookupHoistingModeBit::decode(
          bytecode_flags));
  DCHECK_IMPLIES(lookup_hoisting_mode == LookupHoistingMode::kLegacySloppy,
                 is_sloppy(language_mode));
  const Operator* op = javascript()->CallRuntime(
      is_strict(language_mode)
          ? Runtime::kStoreLookupSlot_Strict
          : lookup_hoisting_mode == LookupHoistingMode::kLegacySloppy
                ? Runtime::kStoreLookupSlot_SloppyHoisting
                : Runtime::kStoreLookupSlot_Sloppy);
  Node* store = NewNode(op, name, value);
  environment()->BindAccumulator(store, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitLdaNamedProperty() {
  PrepareEagerCheckpoint();
  Node* object =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Handle<Name> name =
      Handle<Name>::cast(bytecode_iterator().GetConstantForIndexOperand(1));
  VectorSlotPair feedback =
      CreateVectorSlotPair(bytecode_iterator().GetIndexOperand(2));
  const Operator* op = javascript()->LoadNamed(name, feedback);

  Node* node = nullptr;
  if (Node* simplified =
          TryBuildSimplifiedLoadNamed(op, object, feedback.slot())) {
    if (environment() == nullptr) return;
    node = simplified;
  } else {
    node = NewNode(op, object);
  }

  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitLdaKeyedProperty() {
  PrepareEagerCheckpoint();
  Node* key = environment()->LookupAccumulator();
  Node* object =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  VectorSlotPair feedback =
      CreateVectorSlotPair(bytecode_iterator().GetIndexOperand(1));
  const Operator* op = javascript()->LoadProperty(feedback);

  Node* node = nullptr;
  if (Node* simplified =
          TryBuildSimplifiedLoadKeyed(op, object, key, feedback.slot())) {
    if (environment() == nullptr) return;
    node = simplified;
  } else {
    node = NewNode(op, object, key);
  }

  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::BuildNamedStore(LanguageMode language_mode,
                                           StoreMode store_mode) {
  PrepareEagerCheckpoint();
  Node* value = environment()->LookupAccumulator();
  Node* object =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Handle<Name> name =
      Handle<Name>::cast(bytecode_iterator().GetConstantForIndexOperand(1));
  VectorSlotPair feedback =
      CreateVectorSlotPair(bytecode_iterator().GetIndexOperand(2));

  const Operator* op;
  if (store_mode == StoreMode::kOwn) {
    DCHECK_EQ(FeedbackSlotKind::kStoreOwnNamed,
              feedback.vector()->GetKind(feedback.slot()));
    op = javascript()->StoreNamedOwn(name, feedback);
  } else {
    DCHECK(store_mode == StoreMode::kNormal);
    DCHECK_EQ(feedback.vector()->GetLanguageMode(feedback.slot()),
              language_mode);
    op = javascript()->StoreNamed(language_mode, name, feedback);
  }

  Node* node = nullptr;
  if (Node* simplified =
          TryBuildSimplifiedStoreNamed(op, object, value, feedback.slot())) {
    if (environment() == nullptr) return;
    node = simplified;
  } else {
    node = NewNode(op, object, value);
  }

  environment()->RecordAfterState(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitStaNamedPropertySloppy() {
  BuildNamedStore(LanguageMode::SLOPPY, StoreMode::kNormal);
}

void BytecodeGraphBuilder::VisitStaNamedPropertyStrict() {
  BuildNamedStore(LanguageMode::STRICT, StoreMode::kNormal);
}

void BytecodeGraphBuilder::VisitStaNamedOwnProperty() {
  BuildNamedStore(LanguageMode::STRICT, StoreMode::kOwn);
}

void BytecodeGraphBuilder::BuildKeyedStore(LanguageMode language_mode) {
  PrepareEagerCheckpoint();
  Node* value = environment()->LookupAccumulator();
  Node* object =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* key =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  VectorSlotPair feedback =
      CreateVectorSlotPair(bytecode_iterator().GetIndexOperand(2));
  DCHECK_EQ(feedback.vector()->GetLanguageMode(feedback.slot()), language_mode);
  const Operator* op = javascript()->StoreProperty(language_mode, feedback);

  Node* node = nullptr;
  if (Node* simplified = TryBuildSimplifiedStoreKeyed(op, object, key, value,
                                                      feedback.slot())) {
    if (environment() == nullptr) return;
    node = simplified;
  } else {
    node = NewNode(op, object, key, value);
  }

  environment()->RecordAfterState(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitStaKeyedPropertySloppy() {
  BuildKeyedStore(LanguageMode::SLOPPY);
}

void BytecodeGraphBuilder::VisitStaKeyedPropertyStrict() {
  BuildKeyedStore(LanguageMode::STRICT);
}

void BytecodeGraphBuilder::VisitLdaModuleVariable() {
  int32_t cell_index = bytecode_iterator().GetImmediateOperand(0);
  uint32_t depth = bytecode_iterator().GetUnsignedImmediateOperand(1);
  Node* module =
      NewNode(javascript()->LoadContext(depth, Context::EXTENSION_INDEX, true));
  Node* value = NewNode(javascript()->LoadModule(cell_index), module);
  environment()->BindAccumulator(value);
}

void BytecodeGraphBuilder::VisitStaModuleVariable() {
  int32_t cell_index = bytecode_iterator().GetImmediateOperand(0);
  uint32_t depth = bytecode_iterator().GetUnsignedImmediateOperand(1);
  Node* module =
      NewNode(javascript()->LoadContext(depth, Context::EXTENSION_INDEX, true));
  Node* value = environment()->LookupAccumulator();
  NewNode(javascript()->StoreModule(cell_index), module, value);
}

void BytecodeGraphBuilder::VisitPushContext() {
  Node* new_context = environment()->LookupAccumulator();
  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(0),
                              environment()->Context());
  environment()->SetContext(new_context);
}

void BytecodeGraphBuilder::VisitPopContext() {
  Node* context =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  environment()->SetContext(context);
}

void BytecodeGraphBuilder::VisitCreateClosure() {
  Handle<SharedFunctionInfo> shared_info = Handle<SharedFunctionInfo>::cast(
      bytecode_iterator().GetConstantForIndexOperand(0));
  int const slot_id = bytecode_iterator().GetIndexOperand(1);
  VectorSlotPair pair = CreateVectorSlotPair(slot_id);
  PretenureFlag tenured =
      interpreter::CreateClosureFlags::PretenuredBit::decode(
          bytecode_iterator().GetFlagOperand(2))
          ? TENURED
          : NOT_TENURED;
  const Operator* op = javascript()->CreateClosure(shared_info, pair, tenured);
  Node* closure = NewNode(op);
  environment()->BindAccumulator(closure);
}

void BytecodeGraphBuilder::VisitCreateBlockContext() {
  Handle<ScopeInfo> scope_info = Handle<ScopeInfo>::cast(
      bytecode_iterator().GetConstantForIndexOperand(0));

  const Operator* op = javascript()->CreateBlockContext(scope_info);
  Node* context = NewNode(op, environment()->LookupAccumulator());
  environment()->BindAccumulator(context);
}

void BytecodeGraphBuilder::VisitCreateFunctionContext() {
  uint32_t slots = bytecode_iterator().GetUnsignedImmediateOperand(0);
  const Operator* op =
      javascript()->CreateFunctionContext(slots, FUNCTION_SCOPE);
  Node* context = NewNode(op, GetFunctionClosure());
  environment()->BindAccumulator(context);
}

void BytecodeGraphBuilder::VisitCreateEvalContext() {
  uint32_t slots = bytecode_iterator().GetUnsignedImmediateOperand(0);
  const Operator* op = javascript()->CreateFunctionContext(slots, EVAL_SCOPE);
  Node* context = NewNode(op, GetFunctionClosure());
  environment()->BindAccumulator(context);
}

void BytecodeGraphBuilder::VisitCreateCatchContext() {
  interpreter::Register reg = bytecode_iterator().GetRegisterOperand(0);
  Node* exception = environment()->LookupRegister(reg);
  Handle<String> name =
      Handle<String>::cast(bytecode_iterator().GetConstantForIndexOperand(1));
  Handle<ScopeInfo> scope_info = Handle<ScopeInfo>::cast(
      bytecode_iterator().GetConstantForIndexOperand(2));
  Node* closure = environment()->LookupAccumulator();

  const Operator* op = javascript()->CreateCatchContext(name, scope_info);
  Node* context = NewNode(op, exception, closure);
  environment()->BindAccumulator(context);
}

void BytecodeGraphBuilder::VisitCreateWithContext() {
  Node* object =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Handle<ScopeInfo> scope_info = Handle<ScopeInfo>::cast(
      bytecode_iterator().GetConstantForIndexOperand(1));

  const Operator* op = javascript()->CreateWithContext(scope_info);
  Node* context = NewNode(op, object, environment()->LookupAccumulator());
  environment()->BindAccumulator(context);
}

void BytecodeGraphBuilder::BuildCreateArguments(CreateArgumentsType type) {
  const Operator* op = javascript()->CreateArguments(type);
  Node* object = NewNode(op, GetFunctionClosure());
  environment()->BindAccumulator(object, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitCreateMappedArguments() {
  BuildCreateArguments(CreateArgumentsType::kMappedArguments);
}

void BytecodeGraphBuilder::VisitCreateUnmappedArguments() {
  BuildCreateArguments(CreateArgumentsType::kUnmappedArguments);
}

void BytecodeGraphBuilder::VisitCreateRestParameter() {
  BuildCreateArguments(CreateArgumentsType::kRestParameter);
}

void BytecodeGraphBuilder::VisitCreateRegExpLiteral() {
  Handle<String> constant_pattern =
      Handle<String>::cast(bytecode_iterator().GetConstantForIndexOperand(0));
  int literal_index = bytecode_iterator().GetIndexOperand(1);
  int literal_flags = bytecode_iterator().GetFlagOperand(2);
  Node* literal = NewNode(javascript()->CreateLiteralRegExp(
                              constant_pattern, literal_flags, literal_index),
                          GetFunctionClosure());
  environment()->BindAccumulator(literal, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitCreateArrayLiteral() {
  Handle<ConstantElementsPair> constant_elements =
      Handle<ConstantElementsPair>::cast(
          bytecode_iterator().GetConstantForIndexOperand(0));
  int literal_index = bytecode_iterator().GetIndexOperand(1);
  int bytecode_flags = bytecode_iterator().GetFlagOperand(2);
  int literal_flags =
      interpreter::CreateArrayLiteralFlags::FlagsBits::decode(bytecode_flags);
  // Disable allocation site mementos. Only unoptimized code will collect
  // feedback about allocation site. Once the code is optimized we expect the
  // data to converge. So, we disable allocation site mementos in optimized
  // code. We can revisit this when we have data to the contrary.
  literal_flags |= ArrayLiteral::kDisableMementos;
  // TODO(mstarzinger): Thread through number of elements. The below number is
  // only an estimate and does not match {ArrayLiteral::values::length}.
  int number_of_elements = constant_elements->constant_values()->length();
  Node* literal = NewNode(
      javascript()->CreateLiteralArray(constant_elements, literal_flags,
                                       literal_index, number_of_elements),
      GetFunctionClosure());
  environment()->BindAccumulator(literal, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitCreateObjectLiteral() {
  Handle<BoilerplateDescription> constant_properties =
      Handle<BoilerplateDescription>::cast(
          bytecode_iterator().GetConstantForIndexOperand(0));
  int literal_index = bytecode_iterator().GetIndexOperand(1);
  int bytecode_flags = bytecode_iterator().GetFlagOperand(2);
  int literal_flags =
      interpreter::CreateObjectLiteralFlags::FlagsBits::decode(bytecode_flags);
  // TODO(mstarzinger): Thread through number of properties. The below number is
  // only an estimate and does not match {ObjectLiteral::properties_count}.
  int number_of_properties = constant_properties->size();
  Node* literal = NewNode(
      javascript()->CreateLiteralObject(constant_properties, literal_flags,
                                        literal_index, number_of_properties),
      GetFunctionClosure());
  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(3),
                              literal, Environment::kAttachFrameState);
}

Node* const* BytecodeGraphBuilder::GetCallArgumentsFromRegister(
    Node* callee, Node* receiver, interpreter::Register first_arg,
    int arg_count) {
  // The arity of the Call node -- includes the callee, receiver and function
  // arguments.
  int arity = 2 + arg_count;

  Node** all = local_zone()->NewArray<Node*>(static_cast<size_t>(arity));

  all[0] = callee;
  all[1] = receiver;

  // The function arguments are in consecutive registers.
  int arg_base = first_arg.index();
  for (int i = 0; i < arg_count; ++i) {
    all[2 + i] =
        environment()->LookupRegister(interpreter::Register(arg_base + i));
  }

  return all;
}

Node* BytecodeGraphBuilder::ProcessCallArguments(const Operator* call_op,
                                                 Node* const* args,
                                                 int arg_count) {
  return MakeNode(call_op, arg_count, args, false);
}

Node* BytecodeGraphBuilder::ProcessCallArguments(const Operator* call_op,
                                                 Node* callee,
                                                 interpreter::Register receiver,
                                                 size_t reg_count) {
  Node* receiver_node = environment()->LookupRegister(receiver);
  // The receiver is followed by the arguments in the consecutive registers.
  DCHECK_GE(reg_count, 1);
  interpreter::Register first_arg = interpreter::Register(receiver.index() + 1);
  int arg_count = static_cast<int>(reg_count) - 1;

  Node* const* call_args =
      GetCallArgumentsFromRegister(callee, receiver_node, first_arg, arg_count);
  return ProcessCallArguments(call_op, call_args, 2 + arg_count);
}

void BytecodeGraphBuilder::BuildCall(ConvertReceiverMode receiver_mode,
                                     Node* const* args, size_t arg_count,
                                     int slot_id) {
  DCHECK_EQ(interpreter::Bytecodes::GetReceiverMode(
                bytecode_iterator().current_bytecode()),
            receiver_mode);
  PrepareEagerCheckpoint();

  // Slot index of 0 is used indicate no feedback slot is available. Assert
  // the assumption that slot index 0 is never a valid feedback slot.
  STATIC_ASSERT(FeedbackVector::kReservedIndexCount > 0);
  VectorSlotPair feedback = CreateVectorSlotPair(slot_id);

  CallFrequency frequency = ComputeCallFrequency(slot_id);
  const Operator* op =
      javascript()->Call(arg_count, frequency, feedback, receiver_mode);
  Node* node = nullptr;
  if (Node* simplified = TryBuildSimplifiedCall(
          op, args, static_cast<int>(arg_count), feedback.slot())) {
    if (environment() == nullptr) return;
    node = simplified;
  } else {
    node = ProcessCallArguments(op, args, static_cast<int>(arg_count));
  }
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::BuildCallVarArgs(ConvertReceiverMode receiver_mode) {
  DCHECK_EQ(interpreter::Bytecodes::GetReceiverMode(
                bytecode_iterator().current_bytecode()),
            receiver_mode);
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  interpreter::Register first_reg = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);
  int const slot_id = bytecode_iterator().GetIndexOperand(3);

  Node* receiver_node;
  interpreter::Register first_arg;
  int arg_count;

  if (receiver_mode == ConvertReceiverMode::kNullOrUndefined) {
    // The receiver is implicit (and undefined), the arguments are in
    // consecutive registers.
    receiver_node = jsgraph()->UndefinedConstant();
    first_arg = first_reg;
    arg_count = static_cast<int>(reg_count);
  } else {
    // The receiver is the first register, followed by the arguments in the
    // consecutive registers.
    DCHECK_GE(reg_count, 1);
    receiver_node = environment()->LookupRegister(first_reg);
    first_arg = interpreter::Register(first_reg.index() + 1);
    arg_count = static_cast<int>(reg_count) - 1;
  }

  Node* const* call_args =
      GetCallArgumentsFromRegister(callee, receiver_node, first_arg, arg_count);
  BuildCall(receiver_mode, call_args, static_cast<size_t>(2 + arg_count),
            slot_id);
}

void BytecodeGraphBuilder::VisitCallAnyReceiver() {
  BuildCallVarArgs(ConvertReceiverMode::kAny);
}

void BytecodeGraphBuilder::VisitCallProperty() {
  BuildCallVarArgs(ConvertReceiverMode::kNotNullOrUndefined);
}

void BytecodeGraphBuilder::VisitCallProperty0() {
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* receiver =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  int const slot_id = bytecode_iterator().GetIndexOperand(2);
  BuildCall(ConvertReceiverMode::kNotNullOrUndefined, {callee, receiver},
            slot_id);
}

void BytecodeGraphBuilder::VisitCallProperty1() {
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* receiver =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  Node* arg0 =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(2));
  int const slot_id = bytecode_iterator().GetIndexOperand(3);
  BuildCall(ConvertReceiverMode::kNotNullOrUndefined, {callee, receiver, arg0},
            slot_id);
}

void BytecodeGraphBuilder::VisitCallProperty2() {
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* receiver =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  Node* arg0 =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(2));
  Node* arg1 =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(3));
  int const slot_id = bytecode_iterator().GetIndexOperand(4);
  BuildCall(ConvertReceiverMode::kNotNullOrUndefined,
            {callee, receiver, arg0, arg1}, slot_id);
}

void BytecodeGraphBuilder::VisitCallUndefinedReceiver() {
  BuildCallVarArgs(ConvertReceiverMode::kNullOrUndefined);
}

void BytecodeGraphBuilder::VisitCallUndefinedReceiver0() {
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* receiver = jsgraph()->UndefinedConstant();
  int const slot_id = bytecode_iterator().GetIndexOperand(1);
  BuildCall(ConvertReceiverMode::kNullOrUndefined, {callee, receiver}, slot_id);
}

void BytecodeGraphBuilder::VisitCallUndefinedReceiver1() {
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* receiver = jsgraph()->UndefinedConstant();
  Node* arg0 =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  int const slot_id = bytecode_iterator().GetIndexOperand(2);
  BuildCall(ConvertReceiverMode::kNullOrUndefined, {callee, receiver, arg0},
            slot_id);
}

void BytecodeGraphBuilder::VisitCallUndefinedReceiver2() {
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* receiver = jsgraph()->UndefinedConstant();
  Node* arg0 =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  Node* arg1 =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(2));
  int const slot_id = bytecode_iterator().GetIndexOperand(3);
  BuildCall(ConvertReceiverMode::kNullOrUndefined,
            {callee, receiver, arg0, arg1}, slot_id);
}

void BytecodeGraphBuilder::VisitCallWithSpread() {
  PrepareEagerCheckpoint();
  Node* callee =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  interpreter::Register receiver = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);
  const Operator* call =
      javascript()->CallWithSpread(static_cast<int>(reg_count + 1));

  Node* value = ProcessCallArguments(call, callee, receiver, reg_count);
  environment()->BindAccumulator(value, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitCallJSRuntime() {
  PrepareEagerCheckpoint();
  Node* callee =
      BuildLoadNativeContextField(bytecode_iterator().GetIndexOperand(0));
  interpreter::Register receiver = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);

  // Create node to perform the JS runtime call.
  const Operator* call = javascript()->Call(reg_count + 1);
  Node* value = ProcessCallArguments(call, callee, receiver, reg_count);
  environment()->BindAccumulator(value, Environment::kAttachFrameState);
}

Node* BytecodeGraphBuilder::ProcessCallRuntimeArguments(
    const Operator* call_runtime_op, interpreter::Register receiver,
    size_t reg_count) {
  int arg_count = static_cast<int>(reg_count);
  // arity is args.
  int arity = arg_count;
  Node** all = local_zone()->NewArray<Node*>(static_cast<size_t>(arity));
  int first_arg_index = receiver.index();
  for (int i = 0; i < static_cast<int>(reg_count); ++i) {
    all[i] = environment()->LookupRegister(
        interpreter::Register(first_arg_index + i));
  }
  Node* value = MakeNode(call_runtime_op, arity, all, false);
  return value;
}

void BytecodeGraphBuilder::VisitCallRuntime() {
  PrepareEagerCheckpoint();
  Runtime::FunctionId functionId = bytecode_iterator().GetRuntimeIdOperand(0);
  interpreter::Register receiver = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);

  // Create node to perform the runtime call.
  const Operator* call = javascript()->CallRuntime(functionId, reg_count);
  Node* value = ProcessCallRuntimeArguments(call, receiver, reg_count);
  environment()->BindAccumulator(value, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitCallRuntimeForPair() {
  PrepareEagerCheckpoint();
  Runtime::FunctionId functionId = bytecode_iterator().GetRuntimeIdOperand(0);
  interpreter::Register receiver = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);
  interpreter::Register first_return =
      bytecode_iterator().GetRegisterOperand(3);

  // Create node to perform the runtime call.
  const Operator* call = javascript()->CallRuntime(functionId, reg_count);
  Node* return_pair = ProcessCallRuntimeArguments(call, receiver, reg_count);
  environment()->BindRegistersToProjections(first_return, return_pair,
                                            Environment::kAttachFrameState);
}

Node* const* BytecodeGraphBuilder::GetConstructArgumentsFromRegister(
    Node* target, Node* new_target, interpreter::Register first_arg,
    int arg_count) {
  // arity is args + callee and new target.
  int arity = arg_count + 2;
  Node** all = local_zone()->NewArray<Node*>(static_cast<size_t>(arity));
  all[0] = target;
  int first_arg_index = first_arg.index();
  for (int i = 0; i < arg_count; ++i) {
    all[1 + i] = environment()->LookupRegister(
        interpreter::Register(first_arg_index + i));
  }
  all[arity - 1] = new_target;
  return all;
}

Node* BytecodeGraphBuilder::ProcessConstructArguments(const Operator* op,
                                                      Node* const* args,
                                                      int arg_count) {
  return MakeNode(op, arg_count, args, false);
}

void BytecodeGraphBuilder::VisitConstruct() {
  PrepareEagerCheckpoint();
  interpreter::Register callee_reg = bytecode_iterator().GetRegisterOperand(0);
  interpreter::Register first_reg = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);
  // Slot index of 0 is used indicate no feedback slot is available. Assert
  // the assumption that slot index 0 is never a valid feedback slot.
  STATIC_ASSERT(FeedbackVector::kReservedIndexCount > 0);
  int const slot_id = bytecode_iterator().GetIndexOperand(3);
  VectorSlotPair feedback = CreateVectorSlotPair(slot_id);

  Node* new_target = environment()->LookupAccumulator();
  Node* callee = environment()->LookupRegister(callee_reg);

  CallFrequency frequency = ComputeCallFrequency(slot_id);
  const Operator* op = javascript()->Construct(
      static_cast<uint32_t>(reg_count + 2), frequency, feedback);
  int arg_count = static_cast<int>(reg_count);
  Node* const* args = GetConstructArgumentsFromRegister(callee, new_target,
                                                        first_reg, arg_count);
  Node* node = nullptr;
  if (Node* simplified = TryBuildSimplifiedConstruct(
          op, args, static_cast<int>(arg_count), feedback.slot())) {
    if (environment() == nullptr) return;
    node = simplified;
  } else {
    node = ProcessConstructArguments(op, args, 2 + arg_count);
  }
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitConstructWithSpread() {
  PrepareEagerCheckpoint();
  interpreter::Register callee_reg = bytecode_iterator().GetRegisterOperand(0);
  interpreter::Register first_reg = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);

  Node* new_target = environment()->LookupAccumulator();
  Node* callee = environment()->LookupRegister(callee_reg);

  const Operator* op =
      javascript()->ConstructWithSpread(static_cast<uint32_t>(reg_count + 2));
  int arg_count = static_cast<int>(reg_count);
  Node* const* args = GetConstructArgumentsFromRegister(callee, new_target,
                                                        first_reg, arg_count);
  Node* value = ProcessConstructArguments(op, args, 2 + arg_count);
  environment()->BindAccumulator(value, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitInvokeIntrinsic() {
  PrepareEagerCheckpoint();
  Runtime::FunctionId functionId = bytecode_iterator().GetIntrinsicIdOperand(0);
  interpreter::Register receiver = bytecode_iterator().GetRegisterOperand(1);
  size_t reg_count = bytecode_iterator().GetRegisterCountOperand(2);

  // Create node to perform the runtime call. Turbofan will take care of the
  // lowering.
  const Operator* call = javascript()->CallRuntime(functionId, reg_count);
  Node* value = ProcessCallRuntimeArguments(call, receiver, reg_count);
  environment()->BindAccumulator(value, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitThrow() {
  BuildLoopExitsForFunctionExit();
  Node* value = environment()->LookupAccumulator();
  Node* call = NewNode(javascript()->CallRuntime(Runtime::kThrow), value);
  environment()->BindAccumulator(call, Environment::kAttachFrameState);
  Node* control = NewNode(common()->Throw());
  MergeControlToLeaveFunction(control);
}

void BytecodeGraphBuilder::VisitReThrow() {
  BuildLoopExitsForFunctionExit();
  Node* value = environment()->LookupAccumulator();
  NewNode(javascript()->CallRuntime(Runtime::kReThrow), value);
  Node* control = NewNode(common()->Throw());
  MergeControlToLeaveFunction(control);
}

void BytecodeGraphBuilder::BuildHoleCheckAndThrow(
    Node* condition, Runtime::FunctionId runtime_id, Node* name) {
  Node* accumulator = environment()->LookupAccumulator();
  NewBranch(condition, BranchHint::kFalse);
  {
    SubEnvironment sub_environment(this);

    NewIfTrue();
    Node* node;
    const Operator* op = javascript()->CallRuntime(runtime_id);
    if (runtime_id == Runtime::kThrowReferenceError) {
      DCHECK(name != nullptr);
      node = NewNode(op, name);
    } else {
      DCHECK(runtime_id == Runtime::kThrowSuperAlreadyCalledError ||
             runtime_id == Runtime::kThrowSuperNotCalled);
      node = NewNode(op);
    }
    environment()->RecordAfterState(node, Environment::kAttachFrameState);
    Node* control = NewNode(common()->Throw());
    MergeControlToLeaveFunction(control);
  }
  NewIfFalse();
  environment()->BindAccumulator(accumulator);
}

void BytecodeGraphBuilder::VisitThrowReferenceErrorIfHole() {
  Node* accumulator = environment()->LookupAccumulator();
  Node* check_for_hole = NewNode(simplified()->ReferenceEqual(), accumulator,
                                 jsgraph()->TheHoleConstant());
  Node* name =
      jsgraph()->Constant(bytecode_iterator().GetConstantForIndexOperand(0));
  BuildHoleCheckAndThrow(check_for_hole, Runtime::kThrowReferenceError, name);
}

void BytecodeGraphBuilder::VisitThrowSuperNotCalledIfHole() {
  Node* accumulator = environment()->LookupAccumulator();
  Node* check_for_hole = NewNode(simplified()->ReferenceEqual(), accumulator,
                                 jsgraph()->TheHoleConstant());
  BuildHoleCheckAndThrow(check_for_hole, Runtime::kThrowSuperNotCalled);
}

void BytecodeGraphBuilder::VisitThrowSuperAlreadyCalledIfNotHole() {
  Node* accumulator = environment()->LookupAccumulator();
  Node* check_for_hole = NewNode(simplified()->ReferenceEqual(), accumulator,
                                 jsgraph()->TheHoleConstant());
  Node* check_for_not_hole =
      NewNode(simplified()->BooleanNot(), check_for_hole);
  BuildHoleCheckAndThrow(check_for_not_hole,
                         Runtime::kThrowSuperAlreadyCalledError);
}

void BytecodeGraphBuilder::BuildBinaryOp(const Operator* op) {
  PrepareEagerCheckpoint();
  Node* left =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* right = environment()->LookupAccumulator();

  Node* node = nullptr;
  FeedbackSlot slot = feedback_vector()->ToSlot(
      bytecode_iterator().GetIndexOperand(kBinaryOperationHintIndex));
  if (Node* simplified = TryBuildSimplifiedBinaryOp(op, left, right, slot)) {
    node = simplified;
  } else {
    node = NewNode(op, left, right);
  }

  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

// Helper function to create binary operation hint from the recorded type
// feedback.
BinaryOperationHint BytecodeGraphBuilder::GetBinaryOperationHint(
    int operand_index) {
  FeedbackSlot slot = feedback_vector()->ToSlot(
      bytecode_iterator().GetIndexOperand(operand_index));
  DCHECK_EQ(FeedbackSlotKind::kBinaryOp, feedback_vector()->GetKind(slot));
  BinaryOpICNexus nexus(feedback_vector(), slot);
  return nexus.GetBinaryOperationFeedback();
}

// Helper function to create compare operation hint from the recorded type
// feedback.
CompareOperationHint BytecodeGraphBuilder::GetCompareOperationHint() {
  int slot_index = bytecode_iterator().GetIndexOperand(1);
  if (slot_index == 0) {
    return CompareOperationHint::kAny;
  }
  FeedbackSlot slot =
      feedback_vector()->ToSlot(bytecode_iterator().GetIndexOperand(1));
  DCHECK_EQ(FeedbackSlotKind::kCompareOp, feedback_vector()->GetKind(slot));
  CompareICNexus nexus(feedback_vector(), slot);
  return nexus.GetCompareOperationFeedback();
}

CallFrequency BytecodeGraphBuilder::ComputeCallFrequency(int slot_id) const {
  if (invocation_frequency_.IsUnknown()) return CallFrequency();
  CallICNexus nexus(feedback_vector(), feedback_vector()->ToSlot(slot_id));
  return CallFrequency(nexus.ComputeCallFrequency() *
                       invocation_frequency_.value());
}

void BytecodeGraphBuilder::VisitAdd() {
  BuildBinaryOp(
      javascript()->Add(GetBinaryOperationHint(kBinaryOperationHintIndex)));
}

void BytecodeGraphBuilder::VisitSub() {
  BuildBinaryOp(javascript()->Subtract());
}

void BytecodeGraphBuilder::VisitMul() {
  BuildBinaryOp(javascript()->Multiply());
}

void BytecodeGraphBuilder::VisitDiv() { BuildBinaryOp(javascript()->Divide()); }

void BytecodeGraphBuilder::VisitMod() {
  BuildBinaryOp(javascript()->Modulus());
}

void BytecodeGraphBuilder::VisitBitwiseOr() {
  BuildBinaryOp(javascript()->BitwiseOr());
}

void BytecodeGraphBuilder::VisitBitwiseXor() {
  BuildBinaryOp(javascript()->BitwiseXor());
}

void BytecodeGraphBuilder::VisitBitwiseAnd() {
  BuildBinaryOp(javascript()->BitwiseAnd());
}

void BytecodeGraphBuilder::VisitShiftLeft() {
  BuildBinaryOp(javascript()->ShiftLeft());
}

void BytecodeGraphBuilder::VisitShiftRight() {
  BuildBinaryOp(javascript()->ShiftRight());
}

void BytecodeGraphBuilder::VisitShiftRightLogical() {
  BuildBinaryOp(javascript()->ShiftRightLogical());
}

void BytecodeGraphBuilder::BuildBinaryOpWithImmediate(const Operator* op) {
  PrepareEagerCheckpoint();
  Node* left = environment()->LookupAccumulator();
  Node* right = jsgraph()->Constant(bytecode_iterator().GetImmediateOperand(0));

  Node* node = nullptr;
  FeedbackSlot slot = feedback_vector()->ToSlot(
      bytecode_iterator().GetIndexOperand(kBinaryOperationSmiHintIndex));
  if (Node* simplified = TryBuildSimplifiedBinaryOp(op, left, right, slot)) {
    node = simplified;
  } else {
    node = NewNode(op, left, right);
  }

  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitAddSmi() {
  BuildBinaryOpWithImmediate(
      javascript()->Add(GetBinaryOperationHint(kBinaryOperationSmiHintIndex)));
}

void BytecodeGraphBuilder::VisitSubSmi() {
  BuildBinaryOpWithImmediate(javascript()->Subtract());
}

void BytecodeGraphBuilder::VisitMulSmi() {
  BuildBinaryOpWithImmediate(javascript()->Multiply());
}

void BytecodeGraphBuilder::VisitDivSmi() {
  BuildBinaryOpWithImmediate(javascript()->Divide());
}

void BytecodeGraphBuilder::VisitModSmi() {
  BuildBinaryOpWithImmediate(javascript()->Modulus());
}

void BytecodeGraphBuilder::VisitBitwiseOrSmi() {
  BuildBinaryOpWithImmediate(javascript()->BitwiseOr());
}

void BytecodeGraphBuilder::VisitBitwiseXorSmi() {
  BuildBinaryOpWithImmediate(javascript()->BitwiseXor());
}

void BytecodeGraphBuilder::VisitBitwiseAndSmi() {
  BuildBinaryOpWithImmediate(javascript()->BitwiseAnd());
}

void BytecodeGraphBuilder::VisitShiftLeftSmi() {
  BuildBinaryOpWithImmediate(javascript()->ShiftLeft());
}

void BytecodeGraphBuilder::VisitShiftRightSmi() {
  BuildBinaryOpWithImmediate(javascript()->ShiftRight());
}

void BytecodeGraphBuilder::VisitShiftRightLogicalSmi() {
  BuildBinaryOpWithImmediate(javascript()->ShiftRightLogical());
}

void BytecodeGraphBuilder::VisitInc() {
  PrepareEagerCheckpoint();
  // Note: Use subtract -1 here instead of add 1 to ensure we always convert to
  // a number, not a string.
  Node* left = environment()->LookupAccumulator();
  Node* right = jsgraph()->Constant(-1);
  const Operator* op = javascript()->Subtract();

  Node* node = nullptr;
  FeedbackSlot slot = feedback_vector()->ToSlot(
      bytecode_iterator().GetIndexOperand(kCountOperationHintIndex));
  if (Node* simplified = TryBuildSimplifiedBinaryOp(op, left, right, slot)) {
    node = simplified;
  } else {
    node = NewNode(op, left, right);
  }

  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitDec() {
  PrepareEagerCheckpoint();
  Node* left = environment()->LookupAccumulator();
  Node* right = jsgraph()->OneConstant();
  const Operator* op = javascript()->Subtract();

  Node* node = nullptr;
  FeedbackSlot slot = feedback_vector()->ToSlot(
      bytecode_iterator().GetIndexOperand(kCountOperationHintIndex));
  if (Node* simplified = TryBuildSimplifiedBinaryOp(op, left, right, slot)) {
    node = simplified;
  } else {
    node = NewNode(op, left, right);
  }

  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitLogicalNot() {
  Node* value = environment()->LookupAccumulator();
  Node* node = NewNode(simplified()->BooleanNot(), value);
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitToBooleanLogicalNot() {
  Node* value = NewNode(javascript()->ToBoolean(ToBooleanHint::kAny),
                        environment()->LookupAccumulator());
  Node* node = NewNode(simplified()->BooleanNot(), value);
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitTypeOf() {
  Node* node =
      NewNode(javascript()->TypeOf(), environment()->LookupAccumulator());
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::BuildDelete(LanguageMode language_mode) {
  PrepareEagerCheckpoint();
  Node* key = environment()->LookupAccumulator();
  Node* object =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* mode = jsgraph()->Constant(static_cast<int32_t>(language_mode));
  Node* node = NewNode(javascript()->DeleteProperty(), object, key, mode);
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitDeletePropertyStrict() {
  BuildDelete(LanguageMode::STRICT);
}

void BytecodeGraphBuilder::VisitDeletePropertySloppy() {
  BuildDelete(LanguageMode::SLOPPY);
}

void BytecodeGraphBuilder::VisitGetSuperConstructor() {
  Node* node = NewNode(javascript()->GetSuperConstructor(),
                       environment()->LookupAccumulator());
  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(0), node,
                              Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::BuildCompareOp(const Operator* op) {
  PrepareEagerCheckpoint();
  Node* left =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* right = environment()->LookupAccumulator();

  int slot_index = bytecode_iterator().GetIndexOperand(1);
  DCHECK(slot_index != 0);
  FeedbackSlot slot = feedback_vector()->ToSlot(slot_index);
  Node* node = nullptr;
  if (Node* simplified = TryBuildSimplifiedBinaryOp(op, left, right, slot)) {
    node = simplified;
  } else {
    node = NewNode(op, left, right);
  }
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitTestEqual() {
  BuildCompareOp(javascript()->Equal(GetCompareOperationHint()));
}

void BytecodeGraphBuilder::VisitTestEqualStrict() {
  BuildCompareOp(javascript()->StrictEqual(GetCompareOperationHint()));
}

void BytecodeGraphBuilder::VisitTestLessThan() {
  BuildCompareOp(javascript()->LessThan(GetCompareOperationHint()));
}

void BytecodeGraphBuilder::VisitTestGreaterThan() {
  BuildCompareOp(javascript()->GreaterThan(GetCompareOperationHint()));
}

void BytecodeGraphBuilder::VisitTestLessThanOrEqual() {
  BuildCompareOp(javascript()->LessThanOrEqual(GetCompareOperationHint()));
}

void BytecodeGraphBuilder::VisitTestGreaterThanOrEqual() {
  BuildCompareOp(javascript()->GreaterThanOrEqual(GetCompareOperationHint()));
}

void BytecodeGraphBuilder::VisitTestEqualStrictNoFeedback() {
  // TODO(5310): Currently this is used with both Smi operands and with
  // string operands. We pass string operands for static property check in
  // VisitClassLiteralProperties. This should be changed, so we only use this
  // for Smi operations and lower it to SpeculativeNumberEqual[kSignedSmall]
  PrepareEagerCheckpoint();
  Node* left =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* right = environment()->LookupAccumulator();

  Node* node = NewNode(javascript()->StrictEqual(CompareOperationHint::kAny),
                       left, right);
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::BuildTestingOp(const Operator* op) {
  PrepareEagerCheckpoint();
  Node* left =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* right = environment()->LookupAccumulator();
  Node* node = NewNode(op, left, right);
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitTestIn() {
  BuildTestingOp(javascript()->HasProperty());
}

void BytecodeGraphBuilder::VisitTestInstanceOf() {
  BuildTestingOp(javascript()->InstanceOf());
}

void BytecodeGraphBuilder::VisitTestUndetectable() {
  Node* object = environment()->LookupAccumulator();
  Node* node = NewNode(jsgraph()->simplified()->ObjectIsUndetectable(), object);
  environment()->BindAccumulator(node);
}

void BytecodeGraphBuilder::VisitTestNull() {
  Node* object = environment()->LookupAccumulator();
  Node* result = NewNode(simplified()->ReferenceEqual(), object,
                         jsgraph()->NullConstant());
  environment()->BindAccumulator(result);
}

void BytecodeGraphBuilder::VisitTestUndefined() {
  Node* object = environment()->LookupAccumulator();
  Node* result = NewNode(simplified()->ReferenceEqual(), object,
                         jsgraph()->UndefinedConstant());
  environment()->BindAccumulator(result);
}

void BytecodeGraphBuilder::VisitTestTypeOf() {
  Node* object = environment()->LookupAccumulator();
  auto literal_flag = interpreter::TestTypeOfFlags::Decode(
      bytecode_iterator().GetFlagOperand(0));
  Node* result;
  switch (literal_flag) {
    case interpreter::TestTypeOfFlags::LiteralFlag::kNumber:
      result = NewNode(simplified()->ObjectIsNumber(), object);
      break;
    case interpreter::TestTypeOfFlags::LiteralFlag::kString:
      result = NewNode(simplified()->ObjectIsString(), object);
      break;
    case interpreter::TestTypeOfFlags::LiteralFlag::kSymbol:
      result = NewNode(simplified()->ObjectIsSymbol(), object);
      break;
    case interpreter::TestTypeOfFlags::LiteralFlag::kBoolean:
      result = NewNode(common()->Select(MachineRepresentation::kTagged),
                       NewNode(simplified()->ReferenceEqual(), object,
                               jsgraph()->TrueConstant()),
                       jsgraph()->TrueConstant(),
                       NewNode(simplified()->ReferenceEqual(), object,
                               jsgraph()->FalseConstant()));
      break;
    case interpreter::TestTypeOfFlags::LiteralFlag::kUndefined:
      result = graph()->NewNode(
          common()->Select(MachineRepresentation::kTagged),
          graph()->NewNode(simplified()->ReferenceEqual(), object,
                           jsgraph()->NullConstant()),
          jsgraph()->FalseConstant(),
          graph()->NewNode(simplified()->ObjectIsUndetectable(), object));
      break;
    case interpreter::TestTypeOfFlags::LiteralFlag::kFunction:
      result =
          graph()->NewNode(simplified()->ObjectIsDetectableCallable(), object);
      break;
    case interpreter::TestTypeOfFlags::LiteralFlag::kObject:
      result = graph()->NewNode(
          common()->Select(MachineRepresentation::kTagged),
          graph()->NewNode(simplified()->ObjectIsNonCallable(), object),
          jsgraph()->TrueConstant(),
          graph()->NewNode(simplified()->ReferenceEqual(), object,
                           jsgraph()->NullConstant()));
      break;
    case interpreter::TestTypeOfFlags::LiteralFlag::kOther:
      UNREACHABLE();  // Should never be emitted.
      result = nullptr;
      break;
  }
  environment()->BindAccumulator(result);
}

void BytecodeGraphBuilder::BuildCastOperator(const Operator* js_op) {
  Node* value = NewNode(js_op, environment()->LookupAccumulator());
  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(0), value,
                              Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitToName() {
  BuildCastOperator(javascript()->ToName());
}

void BytecodeGraphBuilder::VisitToObject() {
  BuildCastOperator(javascript()->ToObject());
}

void BytecodeGraphBuilder::VisitToNumber() {
  PrepareEagerCheckpoint();
  Node* object = environment()->LookupAccumulator();

  Node* node = nullptr;
  FeedbackSlot slot =
      feedback_vector()->ToSlot(bytecode_iterator().GetIndexOperand(1));
  if (Node* simplified = TryBuildSimplifiedToNumber(object, slot)) {
    node = simplified;
  } else {
    node = NewNode(javascript()->ToNumber(), object);
  }

  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(0), node,
                              Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitToPrimitiveToString() {
  PrepareEagerCheckpoint();
  Node* object = environment()->LookupAccumulator();

  Node* node = nullptr;
  FeedbackSlot slot =
      feedback_vector()->ToSlot(bytecode_iterator().GetIndexOperand(1));
  if (Node* simplified = TryBuildSimplifiedToPrimitiveToString(object, slot)) {
    node = simplified;
  } else {
    node = NewNode(javascript()->ToPrimitiveToString(), object);
  }

  environment()->BindRegister(bytecode_iterator().GetRegisterOperand(0), node,
                              Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitStringConcat() {
  PrepareEagerCheckpoint();
  interpreter::Register first_reg = bytecode_iterator().GetRegisterOperand(0);
  int operand_count =
      static_cast<int>(bytecode_iterator().GetRegisterCountOperand(1));
  Node** operands =
      local_zone()->NewArray<Node*>(static_cast<size_t>(operand_count));
  int operand_base = first_reg.index();
  for (int i = 0; i < operand_count; ++i) {
    Node* reg =
        environment()->LookupRegister(interpreter::Register(operand_base + i));
    // Explicitly insert a string check here. All operands are already strings,
    // however in the case of generator yields in the middle of string
    // concatenations we might lose the knowledge that the operand is a string.
    operands[i] = NewNode(simplified()->CheckString(), reg);
  }

  Node* node = MakeNode(javascript()->StringConcat(operand_count),
                        operand_count, operands, false);
  environment()->BindAccumulator(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitJump() { BuildJump(); }

void BytecodeGraphBuilder::VisitJumpConstant() { BuildJump(); }

void BytecodeGraphBuilder::VisitJumpIfTrue() { BuildJumpIfTrue(); }

void BytecodeGraphBuilder::VisitJumpIfTrueConstant() { BuildJumpIfTrue(); }

void BytecodeGraphBuilder::VisitJumpIfFalse() { BuildJumpIfFalse(); }

void BytecodeGraphBuilder::VisitJumpIfFalseConstant() { BuildJumpIfFalse(); }

void BytecodeGraphBuilder::VisitJumpIfToBooleanTrue() {
  BuildJumpIfToBooleanTrue();
}

void BytecodeGraphBuilder::VisitJumpIfToBooleanTrueConstant() {
  BuildJumpIfToBooleanTrue();
}

void BytecodeGraphBuilder::VisitJumpIfToBooleanFalse() {
  BuildJumpIfToBooleanFalse();
}

void BytecodeGraphBuilder::VisitJumpIfToBooleanFalseConstant() {
  BuildJumpIfToBooleanFalse();
}

void BytecodeGraphBuilder::VisitJumpIfJSReceiver() { BuildJumpIfJSReceiver(); }

void BytecodeGraphBuilder::VisitJumpIfJSReceiverConstant() {
  BuildJumpIfJSReceiver();
}

void BytecodeGraphBuilder::VisitJumpIfNull() {
  BuildJumpIfEqual(jsgraph()->NullConstant());
}

void BytecodeGraphBuilder::VisitJumpIfNullConstant() {
  BuildJumpIfEqual(jsgraph()->NullConstant());
}

void BytecodeGraphBuilder::VisitJumpIfNotNull() {
  BuildJumpIfNotEqual(jsgraph()->NullConstant());
}

void BytecodeGraphBuilder::VisitJumpIfNotNullConstant() {
  BuildJumpIfNotEqual(jsgraph()->NullConstant());
}

void BytecodeGraphBuilder::VisitJumpIfUndefined() {
  BuildJumpIfEqual(jsgraph()->UndefinedConstant());
}

void BytecodeGraphBuilder::VisitJumpIfUndefinedConstant() {
  BuildJumpIfEqual(jsgraph()->UndefinedConstant());
}

void BytecodeGraphBuilder::VisitJumpIfNotUndefined() {
  BuildJumpIfNotEqual(jsgraph()->UndefinedConstant());
}

void BytecodeGraphBuilder::VisitJumpIfNotUndefinedConstant() {
  BuildJumpIfNotEqual(jsgraph()->UndefinedConstant());
}

void BytecodeGraphBuilder::VisitJumpLoop() { BuildJump(); }

void BytecodeGraphBuilder::BuildSwitchOnSmi(Node* condition) {
  interpreter::JumpTableTargetOffsets offsets =
      bytecode_iterator().GetJumpTableTargetOffsets();

  NewSwitch(condition, offsets.size() + 1);
  for (const auto& entry : offsets) {
    SubEnvironment sub_environment(this);
    NewIfValue(entry.case_value);
    MergeIntoSuccessorEnvironment(entry.target_offset);
  }
  NewIfDefault();
}

void BytecodeGraphBuilder::VisitSwitchOnSmiNoFeedback() {
  PrepareEagerCheckpoint();

  Node* acc = environment()->LookupAccumulator();
  Node* acc_smi = NewNode(simplified()->CheckSmi(), acc);
  BuildSwitchOnSmi(acc_smi);
}

void BytecodeGraphBuilder::VisitStackCheck() {
  PrepareEagerCheckpoint();
  Node* node = NewNode(javascript()->StackCheck());
  environment()->RecordAfterState(node, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitSetPendingMessage() {
  Node* previous_message = NewNode(javascript()->LoadMessage());
  NewNode(javascript()->StoreMessage(), environment()->LookupAccumulator());
  environment()->BindAccumulator(previous_message);
}

void BytecodeGraphBuilder::VisitReturn() {
  BuildLoopExitsForFunctionExit();
  Node* pop_node = jsgraph()->ZeroConstant();
  Node* control =
      NewNode(common()->Return(), pop_node, environment()->LookupAccumulator());
  MergeControlToLeaveFunction(control);
}

void BytecodeGraphBuilder::VisitDebugger() {
  PrepareEagerCheckpoint();
  Node* call = NewNode(javascript()->Debugger());
  environment()->RecordAfterState(call, Environment::kAttachFrameState);
}

// We cannot create a graph from the debugger copy of the bytecode array.
#define DEBUG_BREAK(Name, ...) \
  void BytecodeGraphBuilder::Visit##Name() { UNREACHABLE(); }
DEBUG_BREAK_BYTECODE_LIST(DEBUG_BREAK);
#undef DEBUG_BREAK

void BytecodeGraphBuilder::VisitIncBlockCounter() {
  DCHECK(FLAG_block_coverage);

  Node* closure = GetFunctionClosure();
  Node* coverage_array_slot =
      jsgraph()->Constant(bytecode_iterator().GetIndexOperand(0));

  const Operator* op = javascript()->CallRuntime(Runtime::kIncBlockCounter);

  NewNode(op, closure, coverage_array_slot);
}

void BytecodeGraphBuilder::VisitForInPrepare() {
  PrepareEagerCheckpoint();
  Node* receiver =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* prepare = NewNode(javascript()->ForInPrepare(), receiver);
  environment()->BindRegistersToProjections(
      bytecode_iterator().GetRegisterOperand(1), prepare,
      Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitForInContinue() {
  PrepareEagerCheckpoint();
  Node* index =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* cache_length =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  Node* exit_cond =
      NewNode(javascript()->LessThan(CompareOperationHint::kSignedSmall), index,
              cache_length);
  environment()->BindAccumulator(exit_cond, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitForInNext() {
  PrepareEagerCheckpoint();
  Node* receiver =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  Node* index =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(1));
  int catch_reg_pair_index = bytecode_iterator().GetRegisterOperand(2).index();
  Node* cache_type = environment()->LookupRegister(
      interpreter::Register(catch_reg_pair_index));
  Node* cache_array = environment()->LookupRegister(
      interpreter::Register(catch_reg_pair_index + 1));

  Node* value = NewNode(javascript()->ForInNext(), receiver, cache_array,
                        cache_type, index);
  environment()->BindAccumulator(value, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitForInStep() {
  PrepareEagerCheckpoint();
  Node* index =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  index = NewNode(
      simplified()->SpeculativeNumberAdd(NumberOperationHint::kSignedSmall),
      index, jsgraph()->OneConstant());
  environment()->BindAccumulator(index, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitSuspendGenerator() {
  Node* state = environment()->LookupAccumulator();
  Node* generator = environment()->LookupRegister(
      bytecode_iterator().GetRegisterOperand(0));
  interpreter::Register first_reg = bytecode_iterator().GetRegisterOperand(1);
  // We assume we are storing a range starting from index 0.
  CHECK_EQ(0, first_reg.index());
  int register_count =
      static_cast<int>(bytecode_iterator().GetRegisterCountOperand(2));
  SuspendFlags flags = interpreter::SuspendGeneratorBytecodeFlags::Decode(
      bytecode_iterator().GetFlagOperand(3));

  // The offsets used by the bytecode iterator are relative to a different base
  // than what is used in the interpreter, hence the addition.
  Node* offset =
      jsgraph()->Constant(bytecode_iterator().current_offset() +
                          (BytecodeArray::kHeaderSize - kHeapObjectTag));

  int value_input_count = 3 + register_count;

  Node** value_inputs = local_zone()->NewArray<Node*>(value_input_count);
  value_inputs[0] = generator;
  value_inputs[1] = state;
  value_inputs[2] = offset;
  for (int i = 0; i < register_count; ++i) {
    value_inputs[3 + i] =
        environment()->LookupRegister(interpreter::Register(i));
  }

  MakeNode(javascript()->GeneratorStore(register_count, flags),
           value_input_count, value_inputs, false);
}

void BytecodeGraphBuilder::VisitRestoreGeneratorState() {
  Node* generator = environment()->LookupRegister(
      bytecode_iterator().GetRegisterOperand(0));

  Node* state =
      NewNode(javascript()->GeneratorRestoreContinuation(), generator);

  environment()->BindAccumulator(state, Environment::kAttachFrameState);
}

void BytecodeGraphBuilder::VisitRestoreGeneratorRegisters() {
  Node* generator =
      environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
  interpreter::Register first_reg = bytecode_iterator().GetRegisterOperand(1);
  // We assume we are restoring registers starting fromm index 0.
  CHECK_EQ(0, first_reg.index());
  int register_count =
      static_cast<int>(bytecode_iterator().GetRegisterCountOperand(2));

  // Bijection between registers and array indices must match that used in
  // InterpreterAssembler::ExportRegisterFile.
  for (int i = 0; i < register_count; ++i) {
    Node* value = NewNode(javascript()->GeneratorRestoreRegister(i), generator);
    environment()->BindRegister(interpreter::Register(i), value);
  }
}

void BytecodeGraphBuilder::VisitWide() {
  // Consumed by the BytecodeArrayIterator.
  UNREACHABLE();
}

void BytecodeGraphBuilder::VisitExtraWide() {
  // Consumed by the BytecodeArrayIterator.
  UNREACHABLE();
}

void BytecodeGraphBuilder::VisitIllegal() {
  // Not emitted in valid bytecode.
  UNREACHABLE();
}

void BytecodeGraphBuilder::VisitNop() {}

void BytecodeGraphBuilder::SwitchToMergeEnvironment(int current_offset) {
  auto it = merge_environments_.find(current_offset);
  if (it != merge_environments_.end()) {
    mark_as_needing_eager_checkpoint(true);
    if (environment() != nullptr) {
      it->second->Merge(environment());
    }
    set_environment(it->second);
  }
}

void BytecodeGraphBuilder::BuildLoopHeaderEnvironment(int current_offset) {
  if (bytecode_analysis()->IsLoopHeader(current_offset)) {
    mark_as_needing_eager_checkpoint(true);
    const LoopInfo& loop_info =
        bytecode_analysis()->GetLoopInfoFor(current_offset);

    // Add loop header.
    environment()->PrepareForLoop(loop_info.assignments());

    BuildOSRLoopEntryPoint(current_offset);

    // Store a copy of the environment so we can connect merged back edge inputs
    // to the loop header.
    merge_environments_[current_offset] = environment()->Copy();
  }
}

void BytecodeGraphBuilder::MergeIntoSuccessorEnvironment(int target_offset) {
  BuildLoopExitsForBranch(target_offset);
  Environment*& merge_environment = merge_environments_[target_offset];
  if (merge_environment == nullptr) {
    // Append merge nodes to the environment. We may merge here with another
    // environment. So add a place holder for merge nodes. We may add redundant
    // but will be eliminated in a later pass.
    // TODO(mstarzinger): Be smarter about this!
    NewMerge();
    merge_environment = environment();
  } else {
    merge_environment->Merge(environment());
  }
  set_environment(nullptr);
}

void BytecodeGraphBuilder::MergeControlToLeaveFunction(Node* exit) {
  exit_controls_.push_back(exit);
  set_environment(nullptr);
}

void BytecodeGraphBuilder::BuildOSRLoopEntryPoint(int current_offset) {
  DCHECK(bytecode_analysis()->IsLoopHeader(current_offset));

  if (bytecode_analysis()->IsOSREntryPoint(current_offset)) {
    // For OSR add a special {OsrLoopEntry} node into the current loop header.
    // It will be turned into a usable entry by the OSR deconstruction.
    Environment* osr_env = environment()->Copy();
    osr_env->PrepareForOsrEntry();
    environment()->Merge(osr_env);
  }
}

void BytecodeGraphBuilder::BuildOSRNormalEntryPoint() {
  if (bytecode_analysis()->HasOSREntryPoint()) {
    // For OSR add an {OsrNormalEntry} as the the top-level environment start.
    // It will be replaced with {Dead} by the OSR deconstruction.
    NewNode(common()->OsrNormalEntry());
  }
}

void BytecodeGraphBuilder::BuildLoopExitsForBranch(int target_offset) {
  int origin_offset = bytecode_iterator().current_offset();
  // Only build loop exits for forward edges.
  if (target_offset > origin_offset) {
    BuildLoopExitsUntilLoop(
        bytecode_analysis()->GetLoopOffsetFor(target_offset));
  }
}

void BytecodeGraphBuilder::BuildLoopExitsUntilLoop(int loop_offset) {
  int origin_offset = bytecode_iterator().current_offset();
  int current_loop = bytecode_analysis()->GetLoopOffsetFor(origin_offset);
  while (loop_offset < current_loop) {
    Node* loop_node = merge_environments_[current_loop]->GetControlDependency();
    const LoopInfo& loop_info =
        bytecode_analysis()->GetLoopInfoFor(current_loop);
    environment()->PrepareForLoopExit(loop_node, loop_info.assignments());
    current_loop = loop_info.parent_offset();
  }
}

void BytecodeGraphBuilder::BuildLoopExitsForFunctionExit() {
  BuildLoopExitsUntilLoop(-1);
}

void BytecodeGraphBuilder::BuildJump() {
  MergeIntoSuccessorEnvironment(bytecode_iterator().GetJumpTargetOffset());
}

void BytecodeGraphBuilder::BuildJumpIf(Node* condition) {
  NewBranch(condition);
  {
    SubEnvironment sub_environment(this);
    NewIfTrue();
    MergeIntoSuccessorEnvironment(bytecode_iterator().GetJumpTargetOffset());
  }
  NewIfFalse();
}

void BytecodeGraphBuilder::BuildJumpIfNot(Node* condition) {
  NewBranch(condition);
  {
    SubEnvironment sub_environment(this);
    NewIfFalse();
    MergeIntoSuccessorEnvironment(bytecode_iterator().GetJumpTargetOffset());
  }
  NewIfTrue();
}

void BytecodeGraphBuilder::BuildJumpIfEqual(Node* comperand) {
  Node* accumulator = environment()->LookupAccumulator();
  Node* condition =
      NewNode(simplified()->ReferenceEqual(), accumulator, comperand);
  BuildJumpIf(condition);
}

void BytecodeGraphBuilder::BuildJumpIfNotEqual(Node* comperand) {
  Node* accumulator = environment()->LookupAccumulator();
  Node* condition =
      NewNode(simplified()->ReferenceEqual(), accumulator, comperand);
  BuildJumpIfNot(condition);
}

void BytecodeGraphBuilder::BuildJumpIfFalse() {
  NewBranch(environment()->LookupAccumulator());
  {
    SubEnvironment sub_environment(this);
    NewIfFalse();
    environment()->BindAccumulator(jsgraph()->FalseConstant());
    MergeIntoSuccessorEnvironment(bytecode_iterator().GetJumpTargetOffset());
  }
  NewIfTrue();
  environment()->BindAccumulator(jsgraph()->TrueConstant());
}

void BytecodeGraphBuilder::BuildJumpIfTrue() {
  NewBranch(environment()->LookupAccumulator());
  {
    SubEnvironment sub_environment(this);
    NewIfTrue();
    environment()->BindAccumulator(jsgraph()->TrueConstant());
    MergeIntoSuccessorEnvironment(bytecode_iterator().GetJumpTargetOffset());
  }
  NewIfFalse();
  environment()->BindAccumulator(jsgraph()->FalseConstant());
}

void BytecodeGraphBuilder::BuildJumpIfToBooleanTrue() {
  Node* accumulator = environment()->LookupAccumulator();
  Node* condition =
      NewNode(javascript()->ToBoolean(ToBooleanHint::kAny), accumulator);
  BuildJumpIf(condition);
}

void BytecodeGraphBuilder::BuildJumpIfToBooleanFalse() {
  Node* accumulator = environment()->LookupAccumulator();
  Node* condition =
      NewNode(javascript()->ToBoolean(ToBooleanHint::kAny), accumulator);
  BuildJumpIfNot(condition);
}

void BytecodeGraphBuilder::BuildJumpIfNotHole() {
  Node* accumulator = environment()->LookupAccumulator();
  Node* condition = NewNode(simplified()->ReferenceEqual(), accumulator,
                            jsgraph()->TheHoleConstant());
  BuildJumpIfNot(condition);
}

void BytecodeGraphBuilder::BuildJumpIfJSReceiver() {
  Node* accumulator = environment()->LookupAccumulator();
  Node* condition = NewNode(simplified()->ObjectIsReceiver(), accumulator);
  BuildJumpIf(condition);
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedBinaryOp(const Operator* op,
                                                       Node* left, Node* right,
                                                       FeedbackSlot slot) {
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceBinaryOperation(
      op, left, right, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedToNumber(Node* value,
                                                       FeedbackSlot slot) {
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceToNumberOperation(
      value, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedToPrimitiveToString(
    Node* value, FeedbackSlot slot) {
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction =
      type_hint_lowering().ReduceToPrimitiveToStringOperation(value, effect,
                                                              control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedCall(const Operator* op,
                                                   Node* const* args,
                                                   int arg_count,
                                                   FeedbackSlot slot) {
  // TODO(mstarzinger,6112): This is a workaround for OSR loop entries being
  // pruned from the graph by a soft-deopt. It can happen that a CallIC that
  // control-dominates the OSR entry is still in "uninitialized" state.
  if (!osr_ast_id_.IsNone()) return nullptr;
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceCallOperation(
      op, args, arg_count, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedConstruct(const Operator* op,
                                                        Node* const* args,
                                                        int arg_count,
                                                        FeedbackSlot slot) {
  // TODO(mstarzinger,6112): This is a workaround for OSR loop entries being
  // pruned from the graph by a soft-deopt. It can happen that a CallIC that
  // control-dominates the OSR entry is still in "uninitialized" state.
  if (!osr_ast_id_.IsNone()) return nullptr;
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceConstructOperation(
      op, args, arg_count, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedLoadNamed(const Operator* op,
                                                        Node* receiver,
                                                        FeedbackSlot slot) {
  // TODO(mstarzinger,6112): This is a workaround for OSR loop entries being
  // pruned from the graph by a soft-deopt. It can happen that a LoadIC that
  // control-dominates the OSR entry is still in "uninitialized" state.
  if (bytecode_analysis()->HasOSREntryPoint()) return nullptr;
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceLoadNamedOperation(
      op, receiver, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedLoadKeyed(const Operator* op,
                                                        Node* receiver,
                                                        Node* key,
                                                        FeedbackSlot slot) {
  // TODO(mstarzinger,6112): This is a workaround for OSR loop entries being
  // pruned from the graph by a soft-deopt. It can happen that a LoadIC that
  // control-dominates the OSR entry is still in "uninitialized" state.
  if (bytecode_analysis()->HasOSREntryPoint()) return nullptr;
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceLoadKeyedOperation(
      op, receiver, key, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedStoreNamed(const Operator* op,
                                                         Node* receiver,
                                                         Node* value,
                                                         FeedbackSlot slot) {
  // TODO(mstarzinger,6112): This is a workaround for OSR loop entries being
  // pruned from the graph by a soft-deopt. It can happen that a LoadIC that
  // control-dominates the OSR entry is still in "uninitialized" state.
  if (bytecode_analysis()->HasOSREntryPoint()) return nullptr;
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceStoreNamedOperation(
      op, receiver, value, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

Node* BytecodeGraphBuilder::TryBuildSimplifiedStoreKeyed(const Operator* op,
                                                         Node* receiver,
                                                         Node* key, Node* value,
                                                         FeedbackSlot slot) {
  // TODO(mstarzinger,6112): This is a workaround for OSR loop entries being
  // pruned from the graph by a soft-deopt. It can happen that a LoadIC that
  // control-dominates the OSR entry is still in "uninitialized" state.
  if (bytecode_analysis()->HasOSREntryPoint()) return nullptr;
  Node* effect = environment()->GetEffectDependency();
  Node* control = environment()->GetControlDependency();
  Reduction early_reduction = type_hint_lowering().ReduceStoreKeyedOperation(
      op, receiver, key, value, effect, control, slot);
  if (early_reduction.Changed()) {
    ApplyEarlyReduction(early_reduction);
    return early_reduction.replacement();
  }
  return nullptr;
}

void BytecodeGraphBuilder::ApplyEarlyReduction(Reduction reduction) {
  Node* node = reduction.replacement();
  DCHECK(node->op()->HasProperty(Operator::kNoWrite));
  if (node->op()->EffectOutputCount() > 0) {
    environment()->UpdateEffectDependency(node);
  }
  if (IrOpcode::IsGraphTerminator(node->opcode())) {
    MergeControlToLeaveFunction(node);
  }
}

Node** BytecodeGraphBuilder::EnsureInputBufferSize(int size) {
  if (size > input_buffer_size_) {
    size = size + kInputBufferSizeIncrement + input_buffer_size_;
    input_buffer_ = local_zone()->NewArray<Node*>(size);
    input_buffer_size_ = size;
  }
  return input_buffer_;
}

void BytecodeGraphBuilder::EnterAndExitExceptionHandlers(int current_offset) {
  Handle<HandlerTable> table = exception_handler_table();
  int num_entries = table->NumberOfRangeEntries();

  // Potentially exit exception handlers.
  while (!exception_handlers_.empty()) {
    int current_end = exception_handlers_.top().end_offset_;
    if (current_offset < current_end) break;  // Still covered by range.
    exception_handlers_.pop();
  }

  // Potentially enter exception handlers.
  while (current_exception_handler_ < num_entries) {
    int next_start = table->GetRangeStart(current_exception_handler_);
    if (current_offset < next_start) break;  // Not yet covered by range.
    int next_end = table->GetRangeEnd(current_exception_handler_);
    int next_handler = table->GetRangeHandler(current_exception_handler_);
    int context_register = table->GetRangeData(current_exception_handler_);
    exception_handlers_.push(
        {next_start, next_end, next_handler, context_register});
    current_exception_handler_++;
  }
}

Node* BytecodeGraphBuilder::MakeNode(const Operator* op, int value_input_count,
                                     Node* const* value_inputs,
                                     bool incomplete) {
  DCHECK_EQ(op->ValueInputCount(), value_input_count);

  bool has_context = OperatorProperties::HasContextInput(op);
  bool has_frame_state = OperatorProperties::HasFrameStateInput(op);
  bool has_control = op->ControlInputCount() == 1;
  bool has_effect = op->EffectInputCount() == 1;

  DCHECK_LT(op->ControlInputCount(), 2);
  DCHECK_LT(op->EffectInputCount(), 2);

  Node* result = nullptr;
  if (!has_context && !has_frame_state && !has_control && !has_effect) {
    result = graph()->NewNode(op, value_input_count, value_inputs, incomplete);
  } else {
    bool inside_handler = !exception_handlers_.empty();
    int input_count_with_deps = value_input_count;
    if (has_context) ++input_count_with_deps;
    if (has_frame_state) ++input_count_with_deps;
    if (has_control) ++input_count_with_deps;
    if (has_effect) ++input_count_with_deps;
    Node** buffer = EnsureInputBufferSize(input_count_with_deps);
    memcpy(buffer, value_inputs, kPointerSize * value_input_count);
    Node** current_input = buffer + value_input_count;
    if (has_context) {
      *current_input++ = environment()->Context();
    }
    if (has_frame_state) {
      // The frame state will be inserted later. Here we misuse the {Dead} node
      // as a sentinel to be later overwritten with the real frame state by the
      // calls to {PrepareFrameState} within individual visitor methods.
      *current_input++ = jsgraph()->Dead();
    }
    if (has_effect) {
      *current_input++ = environment()->GetEffectDependency();
    }
    if (has_control) {
      *current_input++ = environment()->GetControlDependency();
    }
    result = graph()->NewNode(op, input_count_with_deps, buffer, incomplete);
    // Update the current control dependency for control-producing nodes.
    if (result->op()->ControlOutputCount() > 0) {
      environment()->UpdateControlDependency(result);
    }
    // Update the current effect dependency for effect-producing nodes.
    if (result->op()->EffectOutputCount() > 0) {
      environment()->UpdateEffectDependency(result);
    }
    // Add implicit exception continuation for throwing nodes.
    if (!result->op()->HasProperty(Operator::kNoThrow) && inside_handler) {
      int handler_offset = exception_handlers_.top().handler_offset_;
      int context_index = exception_handlers_.top().context_register_;
      interpreter::Register context_register(context_index);
      Environment* success_env = environment()->Copy();
      const Operator* op = common()->IfException();
      Node* effect = environment()->GetEffectDependency();
      Node* on_exception = graph()->NewNode(op, effect, result);
      Node* context = environment()->LookupRegister(context_register);
      environment()->UpdateControlDependency(on_exception);
      environment()->UpdateEffectDependency(on_exception);
      environment()->BindAccumulator(on_exception);
      environment()->SetContext(context);
      MergeIntoSuccessorEnvironment(handler_offset);
      set_environment(success_env);
    }
    // Add implicit success continuation for throwing nodes.
    if (!result->op()->HasProperty(Operator::kNoThrow) && inside_handler) {
      const Operator* if_success = common()->IfSuccess();
      Node* on_success = graph()->NewNode(if_success, result);
      environment()->UpdateControlDependency(on_success);
    }
    // Ensure checkpoints are created after operations with side-effects.
    if (has_effect && !result->op()->HasProperty(Operator::kNoWrite)) {
      mark_as_needing_eager_checkpoint(true);
    }
  }

  return result;
}


Node* BytecodeGraphBuilder::NewPhi(int count, Node* input, Node* control) {
  const Operator* phi_op = common()->Phi(MachineRepresentation::kTagged, count);
  Node** buffer = EnsureInputBufferSize(count + 1);
  MemsetPointer(buffer, input, count);
  buffer[count] = control;
  return graph()->NewNode(phi_op, count + 1, buffer, true);
}


Node* BytecodeGraphBuilder::NewEffectPhi(int count, Node* input,
                                         Node* control) {
  const Operator* phi_op = common()->EffectPhi(count);
  Node** buffer = EnsureInputBufferSize(count + 1);
  MemsetPointer(buffer, input, count);
  buffer[count] = control;
  return graph()->NewNode(phi_op, count + 1, buffer, true);
}


Node* BytecodeGraphBuilder::MergeControl(Node* control, Node* other) {
  int inputs = control->op()->ControlInputCount() + 1;
  if (control->opcode() == IrOpcode::kLoop) {
    // Control node for loop exists, add input.
    const Operator* op = common()->Loop(inputs);
    control->AppendInput(graph_zone(), other);
    NodeProperties::ChangeOp(control, op);
  } else if (control->opcode() == IrOpcode::kMerge) {
    // Control node for merge exists, add input.
    const Operator* op = common()->Merge(inputs);
    control->AppendInput(graph_zone(), other);
    NodeProperties::ChangeOp(control, op);
  } else {
    // Control node is a singleton, introduce a merge.
    const Operator* op = common()->Merge(inputs);
    Node* merge_inputs[] = {control, other};
    control = graph()->NewNode(op, arraysize(merge_inputs), merge_inputs, true);
  }
  return control;
}


Node* BytecodeGraphBuilder::MergeEffect(Node* value, Node* other,
                                        Node* control) {
  int inputs = control->op()->ControlInputCount();
  if (value->opcode() == IrOpcode::kEffectPhi &&
      NodeProperties::GetControlInput(value) == control) {
    // Phi already exists, add input.
    value->InsertInput(graph_zone(), inputs - 1, other);
    NodeProperties::ChangeOp(value, common()->EffectPhi(inputs));
  } else if (value != other) {
    // Phi does not exist yet, introduce one.
    value = NewEffectPhi(inputs, value, control);
    value->ReplaceInput(inputs - 1, other);
  }
  return value;
}


Node* BytecodeGraphBuilder::MergeValue(Node* value, Node* other,
                                       Node* control) {
  int inputs = control->op()->ControlInputCount();
  if (value->opcode() == IrOpcode::kPhi &&
      NodeProperties::GetControlInput(value) == control) {
    // Phi already exists, add input.
    value->InsertInput(graph_zone(), inputs - 1, other);
    NodeProperties::ChangeOp(
        value, common()->Phi(MachineRepresentation::kTagged, inputs));
  } else if (value != other) {
    // Phi does not exist yet, introduce one.
    value = NewPhi(inputs, value, control);
    value->ReplaceInput(inputs - 1, other);
  }
  return value;
}

void BytecodeGraphBuilder::UpdateCurrentSourcePosition(
    SourcePositionTableIterator* it, int offset) {
  if (it->done()) return;

  if (it->code_offset() == offset) {
    source_positions_->SetCurrentPosition(SourcePosition(
        it->source_position().ScriptOffset(), start_position_.InliningId()));
    it->Advance();
  } else {
    DCHECK_GT(it->code_offset(), offset);
  }
}

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