Separate CodeAssembler and CodeStubAssembler

src/compiler/code-stub-assembler.cc

Index: src/compiler/code-stub-assembler.cc
diff --git a/src/compiler/code-stub-assembler.cc b/src/compiler/code-stub-assembler.cc
deleted file mode 100644
index 424f5b0116a3d92af36ae8ff677222d3d4348ebc..0000000000000000000000000000000000000000
--- a/src/compiler/code-stub-assembler.cc
+++ /dev/null
@@ -1,1770 +0,0 @@
-// 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/code-stub-assembler.h"
-
-#include <ostream>
-
-#include "src/code-factory.h"
-#include "src/compiler/graph.h"
-#include "src/compiler/instruction-selector.h"
-#include "src/compiler/linkage.h"
-#include "src/compiler/pipeline.h"
-#include "src/compiler/raw-machine-assembler.h"
-#include "src/compiler/schedule.h"
-#include "src/frames.h"
-#include "src/interface-descriptors.h"
-#include "src/interpreter/bytecodes.h"
-#include "src/machine-type.h"
-#include "src/macro-assembler.h"
-#include "src/zone.h"
-
-namespace v8 {
-namespace internal {
-namespace compiler {
-
-CodeStubAssembler::CodeStubAssembler(Isolate* isolate, Zone* zone,
-                                     const CallInterfaceDescriptor& descriptor,
-                                     Code::Flags flags, const char* name,
-                                     size_t result_size)
-    : CodeStubAssembler(
-          isolate, zone,
-          Linkage::GetStubCallDescriptor(
-              isolate, zone, descriptor, descriptor.GetStackParameterCount(),
-              CallDescriptor::kNoFlags, Operator::kNoProperties,
-              MachineType::AnyTagged(), result_size),
-          flags, name) {}
-
-CodeStubAssembler::CodeStubAssembler(Isolate* isolate, Zone* zone,
-                                     int parameter_count, Code::Flags flags,
-                                     const char* name)
-    : CodeStubAssembler(isolate, zone, Linkage::GetJSCallDescriptor(
-                                           zone, false, parameter_count,
-                                           CallDescriptor::kNoFlags),
-                        flags, name) {}
-
-CodeStubAssembler::CodeStubAssembler(Isolate* isolate, Zone* zone,
-                                     CallDescriptor* call_descriptor,
-                                     Code::Flags flags, const char* name)
-    : raw_assembler_(new RawMachineAssembler(
-          isolate, new (zone) Graph(zone), call_descriptor,
-          MachineType::PointerRepresentation(),
-          InstructionSelector::SupportedMachineOperatorFlags())),
-      flags_(flags),
-      name_(name),
-      code_generated_(false),
-      variables_(zone) {}
-
-CodeStubAssembler::~CodeStubAssembler() {}
-
-void CodeStubAssembler::CallPrologue() {}
-
-void CodeStubAssembler::CallEpilogue() {}
-
-Handle<Code> CodeStubAssembler::GenerateCode() {
-  DCHECK(!code_generated_);
-
-  Schedule* schedule = raw_assembler_->Export();
-  Handle<Code> code = Pipeline::GenerateCodeForCodeStub(
-      isolate(), raw_assembler_->call_descriptor(), graph(), schedule, flags_,
-      name_);
-
-  code_generated_ = true;
-  return code;
-}
-
-
-Node* CodeStubAssembler::Int32Constant(int value) {
-  return raw_assembler_->Int32Constant(value);
-}
-
-
-Node* CodeStubAssembler::IntPtrConstant(intptr_t value) {
-  return raw_assembler_->IntPtrConstant(value);
-}
-
-
-Node* CodeStubAssembler::NumberConstant(double value) {
-  return raw_assembler_->NumberConstant(value);
-}
-
-Node* CodeStubAssembler::SmiConstant(Smi* value) {
-  return IntPtrConstant(bit_cast<intptr_t>(value));
-}
-
-Node* CodeStubAssembler::HeapConstant(Handle<HeapObject> object) {
-  return raw_assembler_->HeapConstant(object);
-}
-
-
-Node* CodeStubAssembler::BooleanConstant(bool value) {
-  return raw_assembler_->BooleanConstant(value);
-}
-
-Node* CodeStubAssembler::ExternalConstant(ExternalReference address) {
-  return raw_assembler_->ExternalConstant(address);
-}
-
-Node* CodeStubAssembler::Float64Constant(double value) {
-  return raw_assembler_->Float64Constant(value);
-}
-
-Node* CodeStubAssembler::BooleanMapConstant() {
-  return HeapConstant(isolate()->factory()->boolean_map());
-}
-
-Node* CodeStubAssembler::EmptyStringConstant() {
-  return LoadRoot(Heap::kempty_stringRootIndex);
-}
-
-Node* CodeStubAssembler::HeapNumberMapConstant() {
-  return HeapConstant(isolate()->factory()->heap_number_map());
-}
-
-Node* CodeStubAssembler::NaNConstant() {
-  return LoadRoot(Heap::kNanValueRootIndex);
-}
-
-Node* CodeStubAssembler::NoContextConstant() {
-  return SmiConstant(Smi::FromInt(0));
-}
-
-Node* CodeStubAssembler::NullConstant() {
-  return LoadRoot(Heap::kNullValueRootIndex);
-}
-
-Node* CodeStubAssembler::UndefinedConstant() {
-  return LoadRoot(Heap::kUndefinedValueRootIndex);
-}
-
-Node* CodeStubAssembler::Parameter(int value) {
-  return raw_assembler_->Parameter(value);
-}
-
-void CodeStubAssembler::Return(Node* value) {
-  return raw_assembler_->Return(value);
-}
-
-void CodeStubAssembler::Bind(CodeStubAssembler::Label* label) {
-  return label->Bind();
-}
-
-Node* CodeStubAssembler::LoadFramePointer() {
-  return raw_assembler_->LoadFramePointer();
-}
-
-Node* CodeStubAssembler::LoadParentFramePointer() {
-  return raw_assembler_->LoadParentFramePointer();
-}
-
-Node* CodeStubAssembler::LoadStackPointer() {
-  return raw_assembler_->LoadStackPointer();
-}
-
-Node* CodeStubAssembler::SmiShiftBitsConstant() {
-  return IntPtrConstant(kSmiShiftSize + kSmiTagSize);
-}
-
-Node* CodeStubAssembler::Float64Round(Node* x) {
-  Node* one = Float64Constant(1.0);
-  Node* one_half = Float64Constant(0.5);
-
-  Variable var_x(this, MachineRepresentation::kFloat64);
-  Label return_x(this);
-
-  // Round up {x} towards Infinity.
-  var_x.Bind(Float64Ceil(x));
-
-  GotoIf(Float64LessThanOrEqual(Float64Sub(var_x.value(), one_half), x),
-         &return_x);
-  var_x.Bind(Float64Sub(var_x.value(), one));
-  Goto(&return_x);
-
-  Bind(&return_x);
-  return var_x.value();
-}
-
-Node* CodeStubAssembler::Float64Ceil(Node* x) {
-  if (raw_assembler_->machine()->Float64RoundUp().IsSupported()) {
-    return raw_assembler_->Float64RoundUp(x);
-  }
-
-  Node* one = Float64Constant(1.0);
-  Node* zero = Float64Constant(0.0);
-  Node* two_52 = Float64Constant(4503599627370496.0E0);
-  Node* minus_two_52 = Float64Constant(-4503599627370496.0E0);
-
-  Variable var_x(this, MachineRepresentation::kFloat64);
-  Label return_x(this), return_minus_x(this);
-  var_x.Bind(x);
-
-  // Check if {x} is greater than zero.
-  Label if_xgreaterthanzero(this), if_xnotgreaterthanzero(this);
-  Branch(Float64GreaterThan(x, zero), &if_xgreaterthanzero,
-         &if_xnotgreaterthanzero);
-
-  Bind(&if_xgreaterthanzero);
-  {
-    // Just return {x} unless it's in the range ]0,2^52[.
-    GotoIf(Float64GreaterThanOrEqual(x, two_52), &return_x);
-
-    // Round positive {x} towards Infinity.
-    var_x.Bind(Float64Sub(Float64Add(two_52, x), two_52));
-    GotoUnless(Float64LessThan(var_x.value(), x), &return_x);
-    var_x.Bind(Float64Add(var_x.value(), one));
-    Goto(&return_x);
-  }
-
-  Bind(&if_xnotgreaterthanzero);
-  {
-    // Just return {x} unless it's in the range ]-2^52,0[
-    GotoIf(Float64LessThanOrEqual(x, minus_two_52), &return_x);
-    GotoUnless(Float64LessThan(x, zero), &return_x);
-
-    // Round negated {x} towards Infinity and return the result negated.
-    Node* minus_x = Float64Neg(x);
-    var_x.Bind(Float64Sub(Float64Add(two_52, minus_x), two_52));
-    GotoUnless(Float64GreaterThan(var_x.value(), minus_x), &return_minus_x);
-    var_x.Bind(Float64Sub(var_x.value(), one));
-    Goto(&return_minus_x);
-  }
-
-  Bind(&return_minus_x);
-  var_x.Bind(Float64Neg(var_x.value()));
-  Goto(&return_x);
-
-  Bind(&return_x);
-  return var_x.value();
-}
-
-Node* CodeStubAssembler::Float64Floor(Node* x) {
-  if (raw_assembler_->machine()->Float64RoundDown().IsSupported()) {
-    return raw_assembler_->Float64RoundDown(x);
-  }
-
-  Node* one = Float64Constant(1.0);
-  Node* zero = Float64Constant(0.0);
-  Node* two_52 = Float64Constant(4503599627370496.0E0);
-  Node* minus_two_52 = Float64Constant(-4503599627370496.0E0);
-
-  Variable var_x(this, MachineRepresentation::kFloat64);
-  Label return_x(this), return_minus_x(this);
-  var_x.Bind(x);
-
-  // Check if {x} is greater than zero.
-  Label if_xgreaterthanzero(this), if_xnotgreaterthanzero(this);
-  Branch(Float64GreaterThan(x, zero), &if_xgreaterthanzero,
-         &if_xnotgreaterthanzero);
-
-  Bind(&if_xgreaterthanzero);
-  {
-    // Just return {x} unless it's in the range ]0,2^52[.
-    GotoIf(Float64GreaterThanOrEqual(x, two_52), &return_x);
-
-    // Round positive {x} towards -Infinity.
-    var_x.Bind(Float64Sub(Float64Add(two_52, x), two_52));
-    GotoUnless(Float64GreaterThan(var_x.value(), x), &return_x);
-    var_x.Bind(Float64Sub(var_x.value(), one));
-    Goto(&return_x);
-  }
-
-  Bind(&if_xnotgreaterthanzero);
-  {
-    // Just return {x} unless it's in the range ]-2^52,0[
-    GotoIf(Float64LessThanOrEqual(x, minus_two_52), &return_x);
-    GotoUnless(Float64LessThan(x, zero), &return_x);
-
-    // Round negated {x} towards -Infinity and return the result negated.
-    Node* minus_x = Float64Neg(x);
-    var_x.Bind(Float64Sub(Float64Add(two_52, minus_x), two_52));
-    GotoUnless(Float64LessThan(var_x.value(), minus_x), &return_minus_x);
-    var_x.Bind(Float64Add(var_x.value(), one));
-    Goto(&return_minus_x);
-  }
-
-  Bind(&return_minus_x);
-  var_x.Bind(Float64Neg(var_x.value()));
-  Goto(&return_x);
-
-  Bind(&return_x);
-  return var_x.value();
-}
-
-Node* CodeStubAssembler::Float64Trunc(Node* x) {
-  if (raw_assembler_->machine()->Float64RoundTruncate().IsSupported()) {
-    return raw_assembler_->Float64RoundTruncate(x);
-  }
-
-  Node* one = Float64Constant(1.0);
-  Node* zero = Float64Constant(0.0);
-  Node* two_52 = Float64Constant(4503599627370496.0E0);
-  Node* minus_two_52 = Float64Constant(-4503599627370496.0E0);
-
-  Variable var_x(this, MachineRepresentation::kFloat64);
-  Label return_x(this), return_minus_x(this);
-  var_x.Bind(x);
-
-  // Check if {x} is greater than 0.
-  Label if_xgreaterthanzero(this), if_xnotgreaterthanzero(this);
-  Branch(Float64GreaterThan(x, zero), &if_xgreaterthanzero,
-         &if_xnotgreaterthanzero);
-
-  Bind(&if_xgreaterthanzero);
-  {
-    if (raw_assembler_->machine()->Float64RoundDown().IsSupported()) {
-      var_x.Bind(raw_assembler_->Float64RoundDown(x));
-    } else {
-      // Just return {x} unless it's in the range ]0,2^52[.
-      GotoIf(Float64GreaterThanOrEqual(x, two_52), &return_x);
-
-      // Round positive {x} towards -Infinity.
-      var_x.Bind(Float64Sub(Float64Add(two_52, x), two_52));
-      GotoUnless(Float64GreaterThan(var_x.value(), x), &return_x);
-      var_x.Bind(Float64Sub(var_x.value(), one));
-    }
-    Goto(&return_x);
-  }
-
-  Bind(&if_xnotgreaterthanzero);
-  {
-    if (raw_assembler_->machine()->Float64RoundUp().IsSupported()) {
-      var_x.Bind(raw_assembler_->Float64RoundUp(x));
-      Goto(&return_x);
-    } else {
-      // Just return {x} unless its in the range ]-2^52,0[.
-      GotoIf(Float64LessThanOrEqual(x, minus_two_52), &return_x);
-      GotoUnless(Float64LessThan(x, zero), &return_x);
-
-      // Round negated {x} towards -Infinity and return result negated.
-      Node* minus_x = Float64Neg(x);
-      var_x.Bind(Float64Sub(Float64Add(two_52, minus_x), two_52));
-      GotoUnless(Float64GreaterThan(var_x.value(), minus_x), &return_minus_x);
-      var_x.Bind(Float64Sub(var_x.value(), one));
-      Goto(&return_minus_x);
-    }
-  }
-
-  Bind(&return_minus_x);
-  var_x.Bind(Float64Neg(var_x.value()));
-  Goto(&return_x);
-
-  Bind(&return_x);
-  return var_x.value();
-}
-
-Node* CodeStubAssembler::SmiTag(Node* value) {
-  return raw_assembler_->WordShl(value, SmiShiftBitsConstant());
-}
-
-Node* CodeStubAssembler::SmiUntag(Node* value) {
-  return raw_assembler_->WordSar(value, SmiShiftBitsConstant());
-}
-
-Node* CodeStubAssembler::SmiFromWord32(Node* value) {
-  if (raw_assembler_->machine()->Is64()) {
-    value = raw_assembler_->ChangeInt32ToInt64(value);
-  }
-  return raw_assembler_->WordShl(value, SmiShiftBitsConstant());
-}
-
-Node* CodeStubAssembler::SmiToWord32(Node* value) {
-  Node* result = raw_assembler_->WordSar(value, SmiShiftBitsConstant());
-  if (raw_assembler_->machine()->Is64()) {
-    result = raw_assembler_->TruncateInt64ToInt32(result);
-  }
-  return result;
-}
-
-Node* CodeStubAssembler::SmiToFloat64(Node* value) {
-  return ChangeInt32ToFloat64(SmiUntag(value));
-}
-
-Node* CodeStubAssembler::SmiAdd(Node* a, Node* b) { return IntPtrAdd(a, b); }
-
-Node* CodeStubAssembler::SmiAddWithOverflow(Node* a, Node* b) {
-  return IntPtrAddWithOverflow(a, b);
-}
-
-Node* CodeStubAssembler::SmiSub(Node* a, Node* b) { return IntPtrSub(a, b); }
-
-Node* CodeStubAssembler::SmiSubWithOverflow(Node* a, Node* b) {
-  return IntPtrSubWithOverflow(a, b);
-}
-
-Node* CodeStubAssembler::SmiEqual(Node* a, Node* b) { return WordEqual(a, b); }
-
-Node* CodeStubAssembler::SmiAboveOrEqual(Node* a, Node* b) {
-  return UintPtrGreaterThanOrEqual(a, b);
-}
-
-Node* CodeStubAssembler::SmiLessThan(Node* a, Node* b) {
-  return IntPtrLessThan(a, b);
-}
-
-Node* CodeStubAssembler::SmiLessThanOrEqual(Node* a, Node* b) {
-  return IntPtrLessThanOrEqual(a, b);
-}
-
-Node* CodeStubAssembler::SmiMin(Node* a, Node* b) {
-  // TODO(bmeurer): Consider using Select once available.
-  Variable min(this, MachineRepresentation::kTagged);
-  Label if_a(this), if_b(this), join(this);
-  BranchIfSmiLessThan(a, b, &if_a, &if_b);
-  Bind(&if_a);
-  min.Bind(a);
-  Goto(&join);
-  Bind(&if_b);
-  min.Bind(b);
-  Goto(&join);
-  Bind(&join);
-  return min.value();
-}
-
-#define DEFINE_CODE_STUB_ASSEMBER_BINARY_OP(name)   \
-  Node* CodeStubAssembler::name(Node* a, Node* b) { \
-    return raw_assembler_->name(a, b);              \
-  }
-CODE_STUB_ASSEMBLER_BINARY_OP_LIST(DEFINE_CODE_STUB_ASSEMBER_BINARY_OP)
-#undef DEFINE_CODE_STUB_ASSEMBER_BINARY_OP
-
-Node* CodeStubAssembler::WordShl(Node* value, int shift) {
-  return raw_assembler_->WordShl(value, IntPtrConstant(shift));
-}
-
-#define DEFINE_CODE_STUB_ASSEMBER_UNARY_OP(name) \
-  Node* CodeStubAssembler::name(Node* a) { return raw_assembler_->name(a); }
-CODE_STUB_ASSEMBLER_UNARY_OP_LIST(DEFINE_CODE_STUB_ASSEMBER_UNARY_OP)
-#undef DEFINE_CODE_STUB_ASSEMBER_UNARY_OP
-
-Node* CodeStubAssembler::WordIsSmi(Node* a) {
-  return WordEqual(raw_assembler_->WordAnd(a, IntPtrConstant(kSmiTagMask)),
-                   IntPtrConstant(0));
-}
-
-Node* CodeStubAssembler::WordIsPositiveSmi(Node* a) {
-  return WordEqual(
-      raw_assembler_->WordAnd(a, IntPtrConstant(kSmiTagMask | kSmiSignMask)),
-      IntPtrConstant(0));
-}
-
-Node* CodeStubAssembler::LoadBufferObject(Node* buffer, int offset,
-                                          MachineType rep) {
-  return raw_assembler_->Load(rep, buffer, IntPtrConstant(offset));
-}
-
-Node* CodeStubAssembler::LoadObjectField(Node* object, int offset,
-                                         MachineType rep) {
-  return raw_assembler_->Load(rep, object,
-                              IntPtrConstant(offset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::StoreObjectFieldNoWriteBarrier(
-    Node* object, int offset, Node* value, MachineRepresentation rep) {
-  return StoreNoWriteBarrier(rep, object,
-                             IntPtrConstant(offset - kHeapObjectTag), value);
-}
-
-Node* CodeStubAssembler::LoadHeapNumberValue(Node* object) {
-  return Load(MachineType::Float64(), object,
-              IntPtrConstant(HeapNumber::kValueOffset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::StoreHeapNumberValue(Node* object, Node* value) {
-  return StoreNoWriteBarrier(
-      MachineRepresentation::kFloat64, object,
-      IntPtrConstant(HeapNumber::kValueOffset - kHeapObjectTag), value);
-}
-
-Node* CodeStubAssembler::TruncateHeapNumberValueToWord32(Node* object) {
-  Node* value = LoadHeapNumberValue(object);
-  return raw_assembler_->TruncateFloat64ToInt32(TruncationMode::kJavaScript,
-                                                value);
-}
-
-Node* CodeStubAssembler::LoadMapBitField(Node* map) {
-  return Load(MachineType::Uint8(), map,
-              IntPtrConstant(Map::kBitFieldOffset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::LoadMapBitField2(Node* map) {
-  return Load(MachineType::Uint8(), map,
-              IntPtrConstant(Map::kBitField2Offset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::LoadMapBitField3(Node* map) {
-  return Load(MachineType::Uint32(), map,
-              IntPtrConstant(Map::kBitField3Offset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::LoadMapInstanceType(Node* map) {
-  return Load(MachineType::Uint8(), map,
-              IntPtrConstant(Map::kInstanceTypeOffset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::LoadMapDescriptors(Node* map) {
-  return LoadObjectField(map, Map::kDescriptorsOffset);
-}
-
-Node* CodeStubAssembler::LoadNameHash(Node* name) {
-  return Load(MachineType::Uint32(), name,
-              IntPtrConstant(Name::kHashFieldOffset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::LoadFixedArrayElementInt32Index(
-    Node* object, Node* index, int additional_offset) {
-  Node* header_size = IntPtrConstant(additional_offset +
-                                     FixedArray::kHeaderSize - kHeapObjectTag);
-  if (raw_assembler_->machine()->Is64()) {
-    index = ChangeInt32ToInt64(index);
-  }
-  Node* scaled_index = WordShl(index, IntPtrConstant(kPointerSizeLog2));
-  Node* offset = IntPtrAdd(scaled_index, header_size);
-  return Load(MachineType::AnyTagged(), object, offset);
-}
-
-Node* CodeStubAssembler::LoadMapInstanceSize(Node* map) {
-  return Load(MachineType::Uint8(), map,
-              IntPtrConstant(Map::kInstanceSizeOffset - kHeapObjectTag));
-}
-
-Node* CodeStubAssembler::LoadFixedArrayElementSmiIndex(Node* object,
-                                                       Node* smi_index,
-                                                       int additional_offset) {
-  int const kSmiShiftBits = kSmiShiftSize + kSmiTagSize;
-  Node* header_size = IntPtrConstant(additional_offset +
-                                     FixedArray::kHeaderSize - kHeapObjectTag);
-  Node* scaled_index =
-      (kSmiShiftBits > kPointerSizeLog2)
-          ? WordSar(smi_index, IntPtrConstant(kSmiShiftBits - kPointerSizeLog2))
-          : WordShl(smi_index,
-                    IntPtrConstant(kPointerSizeLog2 - kSmiShiftBits));
-  Node* offset = IntPtrAdd(scaled_index, header_size);
-  return Load(MachineType::AnyTagged(), object, offset);
-}
-
-Node* CodeStubAssembler::LoadFixedArrayElementConstantIndex(Node* object,
-                                                            int index) {
-  Node* offset = IntPtrConstant(FixedArray::kHeaderSize - kHeapObjectTag +
-                                index * kPointerSize);
-  return raw_assembler_->Load(MachineType::AnyTagged(), object, offset);
-}
-
-Node* CodeStubAssembler::StoreFixedArrayElementNoWriteBarrier(Node* object,
-                                                              Node* index,
-                                                              Node* value) {
-  Node* offset =
-      IntPtrAdd(WordShl(index, IntPtrConstant(kPointerSizeLog2)),
-                IntPtrConstant(FixedArray::kHeaderSize - kHeapObjectTag));
-  return StoreNoWriteBarrier(MachineRepresentation::kTagged, object, offset,
-                             value);
-}
-
-Node* CodeStubAssembler::StoreFixedArrayElementInt32Index(Node* object,
-                                                          Node* index,
-                                                          Node* value) {
-  if (raw_assembler_->machine()->Is64()) {
-    index = ChangeInt32ToInt64(index);
-  }
-  Node* offset =
-      IntPtrAdd(WordShl(index, IntPtrConstant(kPointerSizeLog2)),
-                IntPtrConstant(FixedArray::kHeaderSize - kHeapObjectTag));
-  return Store(MachineRepresentation::kTagged, object, offset, value);
-}
-
-Node* CodeStubAssembler::LoadRoot(Heap::RootListIndex root_index) {
-  if (isolate()->heap()->RootCanBeTreatedAsConstant(root_index)) {
-    Handle<Object> root = isolate()->heap()->root_handle(root_index);
-    if (root->IsSmi()) {
-      return SmiConstant(Smi::cast(*root));
-    } else {
-      return HeapConstant(Handle<HeapObject>::cast(root));
-    }
-  }
-
-  compiler::Node* roots_array_start =
-      ExternalConstant(ExternalReference::roots_array_start(isolate()));
-  USE(roots_array_start);
-
-  // TODO(danno): Implement thee root-access case where the root is not constant
-  // and must be loaded from the root array.
-  UNIMPLEMENTED();
-  return nullptr;
-}
-
-Node* CodeStubAssembler::AllocateRawUnaligned(Node* size_in_bytes,
-                                              AllocationFlags flags,
-                                              Node* top_address,
-                                              Node* limit_address) {
-  Node* top = Load(MachineType::Pointer(), top_address);
-  Node* limit = Load(MachineType::Pointer(), limit_address);
-
-  // If there's not enough space, call the runtime.
-  RawMachineLabel runtime_call(RawMachineLabel::kDeferred), no_runtime_call,
-      merge_runtime;
-  raw_assembler_->Branch(
-      raw_assembler_->IntPtrLessThan(IntPtrSub(limit, top), size_in_bytes),
-      &runtime_call, &no_runtime_call);
-
-  raw_assembler_->Bind(&runtime_call);
-  // AllocateInTargetSpace does not use the context.
-  Node* context = IntPtrConstant(0);
-  Node* runtime_flags = SmiTag(Int32Constant(
-      AllocateDoubleAlignFlag::encode(false) |
-      AllocateTargetSpace::encode(flags & kPretenured
-                                      ? AllocationSpace::OLD_SPACE
-                                      : AllocationSpace::NEW_SPACE)));
-  Node* runtime_result = CallRuntime(Runtime::kAllocateInTargetSpace, context,
-                                     SmiTag(size_in_bytes), runtime_flags);
-  raw_assembler_->Goto(&merge_runtime);
-
-  // When there is enough space, return `top' and bump it up.
-  raw_assembler_->Bind(&no_runtime_call);
-  Node* no_runtime_result = top;
-  StoreNoWriteBarrier(MachineType::PointerRepresentation(), top_address,
-                      IntPtrAdd(top, size_in_bytes));
-  no_runtime_result =
-      IntPtrAdd(no_runtime_result, IntPtrConstant(kHeapObjectTag));
-  raw_assembler_->Goto(&merge_runtime);
-
-  raw_assembler_->Bind(&merge_runtime);
-  return raw_assembler_->Phi(MachineType::PointerRepresentation(),
-                             runtime_result, no_runtime_result);
-}
-
-Node* CodeStubAssembler::AllocateRawAligned(Node* size_in_bytes,
-                                            AllocationFlags flags,
-                                            Node* top_address,
-                                            Node* limit_address) {
-  Node* top = Load(MachineType::Pointer(), top_address);
-  Node* limit = Load(MachineType::Pointer(), limit_address);
-  Node* adjusted_size = size_in_bytes;
-  if (flags & kDoubleAlignment) {
-    // TODO(epertoso): Simd128 alignment.
-    RawMachineLabel aligned, not_aligned, merge;
-    raw_assembler_->Branch(WordAnd(top, IntPtrConstant(kDoubleAlignmentMask)),
-                           &not_aligned, &aligned);
-
-    raw_assembler_->Bind(&not_aligned);
-    Node* not_aligned_size =
-        IntPtrAdd(size_in_bytes, IntPtrConstant(kPointerSize));
-    raw_assembler_->Goto(&merge);
-
-    raw_assembler_->Bind(&aligned);
-    raw_assembler_->Goto(&merge);
-
-    raw_assembler_->Bind(&merge);
-    adjusted_size = raw_assembler_->Phi(MachineType::PointerRepresentation(),
-                                        not_aligned_size, adjusted_size);
-  }
-
-  Node* address = AllocateRawUnaligned(adjusted_size, kNone, top, limit);
-
-  RawMachineLabel needs_filler, doesnt_need_filler, merge_address;
-  raw_assembler_->Branch(
-      raw_assembler_->IntPtrEqual(adjusted_size, size_in_bytes),
-      &doesnt_need_filler, &needs_filler);
-
-  raw_assembler_->Bind(&needs_filler);
-  // Store a filler and increase the address by kPointerSize.
-  // TODO(epertoso): this code assumes that we only align to kDoubleSize. Change
-  // it when Simd128 alignment is supported.
-  StoreNoWriteBarrier(MachineType::PointerRepresentation(), top,
-                      LoadRoot(Heap::kOnePointerFillerMapRootIndex));
-  Node* address_with_filler = IntPtrAdd(address, IntPtrConstant(kPointerSize));
-  raw_assembler_->Goto(&merge_address);
-
-  raw_assembler_->Bind(&doesnt_need_filler);
-  Node* address_without_filler = address;
-  raw_assembler_->Goto(&merge_address);
-
-  raw_assembler_->Bind(&merge_address);
-  address = raw_assembler_->Phi(MachineType::PointerRepresentation(),
-                                address_with_filler, address_without_filler);
-  // Update the top.
-  StoreNoWriteBarrier(MachineType::PointerRepresentation(), top_address,
-                      IntPtrAdd(top, adjusted_size));
-  return address;
-}
-
-Node* CodeStubAssembler::Allocate(int size_in_bytes, AllocationFlags flags) {
-  bool const new_space = !(flags & kPretenured);
-  Node* top_address = ExternalConstant(
-      new_space
-          ? ExternalReference::new_space_allocation_top_address(isolate())
-          : ExternalReference::old_space_allocation_top_address(isolate()));
-  Node* limit_address = ExternalConstant(
-      new_space
-          ? ExternalReference::new_space_allocation_limit_address(isolate())
-          : ExternalReference::old_space_allocation_limit_address(isolate()));
-
-#ifdef V8_HOST_ARCH_32_BIT
-  if (flags & kDoubleAlignment) {
-    return AllocateRawAligned(IntPtrConstant(size_in_bytes), flags, top_address,
-                              limit_address);
-  }
-#endif
-
-  return AllocateRawUnaligned(IntPtrConstant(size_in_bytes), flags, top_address,
-                              limit_address);
-}
-
-Node* CodeStubAssembler::InnerAllocate(Node* previous, int offset) {
-  return IntPtrAdd(previous, IntPtrConstant(offset));
-}
-
-Node* CodeStubAssembler::AllocateHeapNumber() {
-  Node* result = Allocate(HeapNumber::kSize, kNone);
-  StoreMapNoWriteBarrier(result, HeapNumberMapConstant());
-  return result;
-}
-
-Node* CodeStubAssembler::AllocateHeapNumberWithValue(Node* value) {
-  Node* result = AllocateHeapNumber();
-  StoreHeapNumberValue(result, value);
-  return result;
-}
-
-Node* CodeStubAssembler::AllocateSeqOneByteString(int length) {
-  Node* result = Allocate(SeqOneByteString::SizeFor(length));
-  StoreMapNoWriteBarrier(result, LoadRoot(Heap::kOneByteStringMapRootIndex));
-  StoreObjectFieldNoWriteBarrier(result, SeqOneByteString::kLengthOffset,
-                                 SmiConstant(Smi::FromInt(length)));
-  StoreObjectFieldNoWriteBarrier(result, SeqOneByteString::kHashFieldOffset,
-                                 IntPtrConstant(String::kEmptyHashField));
-  return result;
-}
-
-Node* CodeStubAssembler::AllocateSeqTwoByteString(int length) {
-  Node* result = Allocate(SeqTwoByteString::SizeFor(length));
-  StoreMapNoWriteBarrier(result, LoadRoot(Heap::kStringMapRootIndex));
-  StoreObjectFieldNoWriteBarrier(result, SeqTwoByteString::kLengthOffset,
-                                 SmiConstant(Smi::FromInt(length)));
-  StoreObjectFieldNoWriteBarrier(result, SeqTwoByteString::kHashFieldOffset,
-                                 IntPtrConstant(String::kEmptyHashField));
-  return result;
-}
-
-Node* CodeStubAssembler::Load(MachineType rep, Node* base) {
-  return raw_assembler_->Load(rep, base);
-}
-
-Node* CodeStubAssembler::Load(MachineType rep, Node* base, Node* index) {
-  return raw_assembler_->Load(rep, base, index);
-}
-
-Node* CodeStubAssembler::Store(MachineRepresentation rep, Node* base,
-                               Node* value) {
-  return raw_assembler_->Store(rep, base, value, kFullWriteBarrier);
-}
-
-Node* CodeStubAssembler::Store(MachineRepresentation rep, Node* base,
-                               Node* index, Node* value) {
-  return raw_assembler_->Store(rep, base, index, value, kFullWriteBarrier);
-}
-
-Node* CodeStubAssembler::StoreNoWriteBarrier(MachineRepresentation rep,
-                                             Node* base, Node* value) {
-  return raw_assembler_->Store(rep, base, value, kNoWriteBarrier);
-}
-
-Node* CodeStubAssembler::StoreNoWriteBarrier(MachineRepresentation rep,
-                                             Node* base, Node* index,
-                                             Node* value) {
-  return raw_assembler_->Store(rep, base, index, value, kNoWriteBarrier);
-}
-
-Node* CodeStubAssembler::Projection(int index, Node* value) {
-  return raw_assembler_->Projection(index, value);
-}
-
-Node* CodeStubAssembler::LoadMap(Node* object) {
-  return LoadObjectField(object, HeapObject::kMapOffset);
-}
-
-Node* CodeStubAssembler::StoreMapNoWriteBarrier(Node* object, Node* map) {
-  return StoreNoWriteBarrier(
-      MachineRepresentation::kTagged, object,
-      IntPtrConstant(HeapNumber::kMapOffset - kHeapObjectTag), map);
-}
-
-Node* CodeStubAssembler::LoadInstanceType(Node* object) {
-  return LoadMapInstanceType(LoadMap(object));
-}
-
-Node* CodeStubAssembler::LoadElements(Node* object) {
-  return LoadObjectField(object, JSObject::kElementsOffset);
-}
-
-Node* CodeStubAssembler::LoadFixedArrayBaseLength(Node* array) {
-  return LoadObjectField(array, FixedArrayBase::kLengthOffset);
-}
-
-Node* CodeStubAssembler::BitFieldDecode(Node* word32, uint32_t shift,
-                                        uint32_t mask) {
-  return raw_assembler_->Word32Shr(
-      raw_assembler_->Word32And(word32, raw_assembler_->Int32Constant(mask)),
-      raw_assembler_->Int32Constant(shift));
-}
-
-Node* CodeStubAssembler::ChangeFloat64ToTagged(Node* value) {
-  Node* value32 = raw_assembler_->TruncateFloat64ToInt32(
-      TruncationMode::kRoundToZero, value);
-  Node* value64 = ChangeInt32ToFloat64(value32);
-
-  Label if_valueisint32(this), if_valueisheapnumber(this), if_join(this);
-
-  Label if_valueisequal(this), if_valueisnotequal(this);
-  Branch(Float64Equal(value, value64), &if_valueisequal, &if_valueisnotequal);
-  Bind(&if_valueisequal);
-  {
-    Label if_valueiszero(this), if_valueisnotzero(this);
-    Branch(Float64Equal(value, Float64Constant(0.0)), &if_valueiszero,
-           &if_valueisnotzero);
-
-    Bind(&if_valueiszero);
-    BranchIfInt32LessThan(raw_assembler_->Float64ExtractHighWord32(value),
-                          Int32Constant(0), &if_valueisheapnumber,
-                          &if_valueisint32);
-
-    Bind(&if_valueisnotzero);
-    Goto(&if_valueisint32);
-  }
-  Bind(&if_valueisnotequal);
-  Goto(&if_valueisheapnumber);
-
-  Variable var_result(this, MachineRepresentation::kTagged);
-  Bind(&if_valueisint32);
-  {
-    if (raw_assembler_->machine()->Is64()) {
-      Node* result = SmiTag(ChangeInt32ToInt64(value32));
-      var_result.Bind(result);
-      Goto(&if_join);
-    } else {
-      Node* pair = Int32AddWithOverflow(value32, value32);
-      Node* overflow = Projection(1, pair);
-      Label if_overflow(this, Label::kDeferred), if_notoverflow(this);
-      Branch(overflow, &if_overflow, &if_notoverflow);
-      Bind(&if_overflow);
-      Goto(&if_valueisheapnumber);
-      Bind(&if_notoverflow);
-      {
-        Node* result = Projection(0, pair);
-        var_result.Bind(result);
-        Goto(&if_join);
-      }
-    }
-  }
-  Bind(&if_valueisheapnumber);
-  {
-    Node* result = AllocateHeapNumberWithValue(value);
-    var_result.Bind(result);
-    Goto(&if_join);
-  }
-  Bind(&if_join);
-  return var_result.value();
-}
-
-Node* CodeStubAssembler::ChangeInt32ToTagged(Node* value) {
-  if (raw_assembler_->machine()->Is64()) {
-    return SmiTag(ChangeInt32ToInt64(value));
-  }
-  Variable var_result(this, MachineRepresentation::kTagged);
-  Node* pair = Int32AddWithOverflow(value, value);
-  Node* overflow = Projection(1, pair);
-  Label if_overflow(this, Label::kDeferred), if_notoverflow(this),
-      if_join(this);
-  Branch(overflow, &if_overflow, &if_notoverflow);
-  Bind(&if_overflow);
-  {
-    Node* value64 = ChangeInt32ToFloat64(value);
-    Node* result = AllocateHeapNumberWithValue(value64);
-    var_result.Bind(result);
-  }
-  Goto(&if_join);
-  Bind(&if_notoverflow);
-  {
-    Node* result = Projection(0, pair);
-    var_result.Bind(result);
-  }
-  Goto(&if_join);
-  Bind(&if_join);
-  return var_result.value();
-}
-
-Node* CodeStubAssembler::ChangeUint32ToTagged(Node* value) {
-  Label if_overflow(this, Label::kDeferred), if_not_overflow(this),
-      if_join(this);
-  Variable var_result(this, MachineRepresentation::kTagged);
-  // If {value} > 2^31 - 1, we need to store it in a HeapNumber.
-  Branch(Int32LessThan(value, Int32Constant(0)), &if_overflow,
-         &if_not_overflow);
-  Bind(&if_not_overflow);
-  {
-    if (raw_assembler_->machine()->Is64()) {
-      var_result.Bind(SmiTag(ChangeUint32ToUint64(value)));
-    } else {
-      // If tagging {value} results in an overflow, we need to use a HeapNumber
-      // to represent it.
-      Node* pair = Int32AddWithOverflow(value, value);
-      Node* overflow = Projection(1, pair);
-      GotoIf(overflow, &if_overflow);
-
-      Node* result = Projection(0, pair);
-      var_result.Bind(result);
-    }
-  }
-  Goto(&if_join);
-
-  Bind(&if_overflow);
-  {
-    Node* float64_value = ChangeUint32ToFloat64(value);
-    var_result.Bind(AllocateHeapNumberWithValue(float64_value));
-  }
-  Goto(&if_join);
-
-  Bind(&if_join);
-  return var_result.value();
-}
-
-Node* CodeStubAssembler::TruncateTaggedToFloat64(Node* context, Node* value) {
-  // We might need to loop once due to ToNumber conversion.
-  Variable var_value(this, MachineRepresentation::kTagged),
-      var_result(this, MachineRepresentation::kFloat64);
-  Label loop(this, &var_value), done_loop(this, &var_result);
-  var_value.Bind(value);
-  Goto(&loop);
-  Bind(&loop);
-  {
-    // Load the current {value}.
-    value = var_value.value();
-
-    // Check if the {value} is a Smi or a HeapObject.
-    Label if_valueissmi(this), if_valueisnotsmi(this);
-    Branch(WordIsSmi(value), &if_valueissmi, &if_valueisnotsmi);
-
-    Bind(&if_valueissmi);
-    {
-      // Convert the Smi {value}.
-      var_result.Bind(SmiToFloat64(value));
-      Goto(&done_loop);
-    }
-
-    Bind(&if_valueisnotsmi);
-    {
-      // Check if {value} is a HeapNumber.
-      Label if_valueisheapnumber(this),
-          if_valueisnotheapnumber(this, Label::kDeferred);
-      Branch(WordEqual(LoadMap(value), HeapNumberMapConstant()),
-             &if_valueisheapnumber, &if_valueisnotheapnumber);
-
-      Bind(&if_valueisheapnumber);
-      {
-        // Load the floating point value.
-        var_result.Bind(LoadHeapNumberValue(value));
-        Goto(&done_loop);
-      }
-
-      Bind(&if_valueisnotheapnumber);
-      {
-        // Convert the {value} to a Number first.
-        Callable callable = CodeFactory::NonNumberToNumber(isolate());
-        var_value.Bind(CallStub(callable, context, value));
-        Goto(&loop);
-      }
-    }
-  }
-  Bind(&done_loop);
-  return var_result.value();
-}
-
-Node* CodeStubAssembler::TruncateTaggedToWord32(Node* context, Node* value) {
-  // We might need to loop once due to ToNumber conversion.
-  Variable var_value(this, MachineRepresentation::kTagged),
-      var_result(this, MachineRepresentation::kWord32);
-  Label loop(this, &var_value), done_loop(this, &var_result);
-  var_value.Bind(value);
-  Goto(&loop);
-  Bind(&loop);
-  {
-    // Load the current {value}.
-    value = var_value.value();
-
-    // Check if the {value} is a Smi or a HeapObject.
-    Label if_valueissmi(this), if_valueisnotsmi(this);
-    Branch(WordIsSmi(value), &if_valueissmi, &if_valueisnotsmi);
-
-    Bind(&if_valueissmi);
-    {
-      // Convert the Smi {value}.
-      var_result.Bind(SmiToWord32(value));
-      Goto(&done_loop);
-    }
-
-    Bind(&if_valueisnotsmi);
-    {
-      // Check if {value} is a HeapNumber.
-      Label if_valueisheapnumber(this),
-          if_valueisnotheapnumber(this, Label::kDeferred);
-      Branch(WordEqual(LoadMap(value), HeapNumberMapConstant()),
-             &if_valueisheapnumber, &if_valueisnotheapnumber);
-
-      Bind(&if_valueisheapnumber);
-      {
-        // Truncate the floating point value.
-        var_result.Bind(TruncateHeapNumberValueToWord32(value));
-        Goto(&done_loop);
-      }
-
-      Bind(&if_valueisnotheapnumber);
-      {
-        // Convert the {value} to a Number first.
-        Callable callable = CodeFactory::NonNumberToNumber(isolate());
-        var_value.Bind(CallStub(callable, context, value));
-        Goto(&loop);
-      }
-    }
-  }
-  Bind(&done_loop);
-  return var_result.value();
-}
-
-Node* CodeStubAssembler::ToThisString(Node* context, Node* value,
-                                      char const* method_name) {
-  Variable var_value(this, MachineRepresentation::kTagged);
-  var_value.Bind(value);
-
-  // Check if the {value} is a Smi or a HeapObject.
-  Label if_valueissmi(this, Label::kDeferred), if_valueisnotsmi(this),
-      if_valueisstring(this);
-  Branch(WordIsSmi(value), &if_valueissmi, &if_valueisnotsmi);
-  Bind(&if_valueisnotsmi);
-  {
-    // Load the instance type of the {value}.
-    Node* value_instance_type = LoadInstanceType(value);
-
-    // Check if the {value} is already String.
-    Label if_valueisnotstring(this, Label::kDeferred);
-    Branch(
-        Int32LessThan(value_instance_type, Int32Constant(FIRST_NONSTRING_TYPE)),
-        &if_valueisstring, &if_valueisnotstring);
-    Bind(&if_valueisnotstring);
-    {
-      // Check if the {value} is null.
-      Label if_valueisnullorundefined(this, Label::kDeferred),
-          if_valueisnotnullorundefined(this, Label::kDeferred),
-          if_valueisnotnull(this, Label::kDeferred);
-      Branch(WordEqual(value, NullConstant()), &if_valueisnullorundefined,
-             &if_valueisnotnull);
-      Bind(&if_valueisnotnull);
-      {
-        // Check if the {value} is undefined.
-        Branch(WordEqual(value, UndefinedConstant()),
-               &if_valueisnullorundefined, &if_valueisnotnullorundefined);
-        Bind(&if_valueisnotnullorundefined);
-        {
-          // Convert the {value} to a String.
-          Callable callable = CodeFactory::ToString(isolate());
-          var_value.Bind(CallStub(callable, context, value));
-          Goto(&if_valueisstring);
-        }
-      }
-
-      Bind(&if_valueisnullorundefined);
-      {
-        // The {value} is either null or undefined.
-        CallRuntime(Runtime::kThrowCalledOnNullOrUndefined, context,
-                    HeapConstant(factory()->NewStringFromAsciiChecked(
-                        method_name, TENURED)));
-        Goto(&if_valueisstring);  // Never reached.
-      }
-    }
-  }
-  Bind(&if_valueissmi);
-  {
-    // The {value} is a Smi, convert it to a String.
-    Callable callable = CodeFactory::NumberToString(isolate());
-    var_value.Bind(CallStub(callable, context, value));
-    Goto(&if_valueisstring);
-  }
-  Bind(&if_valueisstring);
-  return var_value.value();
-}
-
-Node* CodeStubAssembler::StringCharCodeAt(Node* string, Node* index) {
-  // Translate the {index} into a Word.
-  index = SmiToWord(index);
-
-  // We may need to loop in case of cons or sliced strings.
-  Variable var_index(this, MachineType::PointerRepresentation());
-  Variable var_result(this, MachineRepresentation::kWord32);
-  Variable var_string(this, MachineRepresentation::kTagged);
-  Variable* loop_vars[] = {&var_index, &var_string};
-  Label done_loop(this, &var_result), loop(this, 2, loop_vars);
-  var_string.Bind(string);
-  var_index.Bind(index);
-  Goto(&loop);
-  Bind(&loop);
-  {
-    // Load the current {index}.
-    index = var_index.value();
-
-    // Load the current {string}.
-    string = var_string.value();
-
-    // Load the instance type of the {string}.
-    Node* string_instance_type = LoadInstanceType(string);
-
-    // Check if the {string} is a SeqString.
-    Label if_stringissequential(this), if_stringisnotsequential(this);
-    Branch(Word32Equal(Word32And(string_instance_type,
-                                 Int32Constant(kStringRepresentationMask)),
-                       Int32Constant(kSeqStringTag)),
-           &if_stringissequential, &if_stringisnotsequential);
-
-    Bind(&if_stringissequential);
-    {
-      // Check if the {string} is a TwoByteSeqString or a OneByteSeqString.
-      Label if_stringistwobyte(this), if_stringisonebyte(this);
-      Branch(Word32Equal(Word32And(string_instance_type,
-                                   Int32Constant(kStringEncodingMask)),
-                         Int32Constant(kTwoByteStringTag)),
-             &if_stringistwobyte, &if_stringisonebyte);
-
-      Bind(&if_stringisonebyte);
-      {
-        var_result.Bind(
-            Load(MachineType::Uint8(), string,
-                 IntPtrAdd(index, IntPtrConstant(SeqOneByteString::kHeaderSize -
-                                                 kHeapObjectTag))));
-        Goto(&done_loop);
-      }
-
-      Bind(&if_stringistwobyte);
-      {
-        var_result.Bind(
-            Load(MachineType::Uint16(), string,
-                 IntPtrAdd(WordShl(index, IntPtrConstant(1)),
-                           IntPtrConstant(SeqTwoByteString::kHeaderSize -
-                                          kHeapObjectTag))));
-        Goto(&done_loop);
-      }
-    }
-
-    Bind(&if_stringisnotsequential);
-    {
-      // Check if the {string} is a ConsString.
-      Label if_stringiscons(this), if_stringisnotcons(this);
-      Branch(Word32Equal(Word32And(string_instance_type,
-                                   Int32Constant(kStringRepresentationMask)),
-                         Int32Constant(kConsStringTag)),
-             &if_stringiscons, &if_stringisnotcons);
-
-      Bind(&if_stringiscons);
-      {
-        // Check whether the right hand side is the empty string (i.e. if
-        // this is really a flat string in a cons string). If that is not
-        // the case we flatten the string first.
-        Label if_rhsisempty(this), if_rhsisnotempty(this, Label::kDeferred);
-        Node* rhs = LoadObjectField(string, ConsString::kSecondOffset);
-        Branch(WordEqual(rhs, EmptyStringConstant()), &if_rhsisempty,
-               &if_rhsisnotempty);
-
-        Bind(&if_rhsisempty);
-        {
-          // Just operate on the left hand side of the {string}.
-          var_string.Bind(LoadObjectField(string, ConsString::kFirstOffset));
-          Goto(&loop);
-        }
-
-        Bind(&if_rhsisnotempty);
-        {
-          // Flatten the {string} and lookup in the resulting string.
-          var_string.Bind(CallRuntime(Runtime::kFlattenString,
-                                      NoContextConstant(), string));
-          Goto(&loop);
-        }
-      }
-
-      Bind(&if_stringisnotcons);
-      {
-        // Check if the {string} is an ExternalString.
-        Label if_stringisexternal(this), if_stringisnotexternal(this);
-        Branch(Word32Equal(Word32And(string_instance_type,
-                                     Int32Constant(kStringRepresentationMask)),
-                           Int32Constant(kExternalStringTag)),
-               &if_stringisexternal, &if_stringisnotexternal);
-
-        Bind(&if_stringisexternal);
-        {
-          // Check if the {string} is a short external string.
-          Label if_stringisshort(this),
-              if_stringisnotshort(this, Label::kDeferred);
-          Branch(Word32Equal(Word32And(string_instance_type,
-                                       Int32Constant(kShortExternalStringMask)),
-                             Int32Constant(0)),
-                 &if_stringisshort, &if_stringisnotshort);
-
-          Bind(&if_stringisshort);
-          {
-            // Load the actual resource data from the {string}.
-            Node* string_resource_data =
-                LoadObjectField(string, ExternalString::kResourceDataOffset,
-                                MachineType::Pointer());
-
-            // Check if the {string} is a TwoByteExternalString or a
-            // OneByteExternalString.
-            Label if_stringistwobyte(this), if_stringisonebyte(this);
-            Branch(Word32Equal(Word32And(string_instance_type,
-                                         Int32Constant(kStringEncodingMask)),
-                               Int32Constant(kTwoByteStringTag)),
-                   &if_stringistwobyte, &if_stringisonebyte);
-
-            Bind(&if_stringisonebyte);
-            {
-              var_result.Bind(
-                  Load(MachineType::Uint8(), string_resource_data, index));
-              Goto(&done_loop);
-            }
-
-            Bind(&if_stringistwobyte);
-            {
-              var_result.Bind(Load(MachineType::Uint16(), string_resource_data,
-                                   WordShl(index, IntPtrConstant(1))));
-              Goto(&done_loop);
-            }
-          }
-
-          Bind(&if_stringisnotshort);
-          {
-            // The {string} might be compressed, call the runtime.
-            var_result.Bind(SmiToWord32(
-                CallRuntime(Runtime::kExternalStringGetChar,
-                            NoContextConstant(), string, SmiTag(index))));
-            Goto(&done_loop);
-          }
-        }
-
-        Bind(&if_stringisnotexternal);
-        {
-          // The {string} is a SlicedString, continue with its parent.
-          Node* string_offset =
-              SmiToWord(LoadObjectField(string, SlicedString::kOffsetOffset));
-          Node* string_parent =
-              LoadObjectField(string, SlicedString::kParentOffset);
-          var_index.Bind(IntPtrAdd(index, string_offset));
-          var_string.Bind(string_parent);
-          Goto(&loop);
-        }
-      }
-    }
-  }
-
-  Bind(&done_loop);
-  return var_result.value();
-}
-
-Node* CodeStubAssembler::StringFromCharCode(Node* code) {
-  Variable var_result(this, MachineRepresentation::kTagged);
-
-  // Check if the {code} is a one-byte char code.
-  Label if_codeisonebyte(this), if_codeistwobyte(this, Label::kDeferred),
-      if_done(this);
-  Branch(Int32LessThanOrEqual(code, Int32Constant(String::kMaxOneByteCharCode)),
-         &if_codeisonebyte, &if_codeistwobyte);
-  Bind(&if_codeisonebyte);
-  {
-    // Load the isolate wide single character string cache.
-    Node* cache = LoadRoot(Heap::kSingleCharacterStringCacheRootIndex);
-
-    // Check if we have an entry for the {code} in the single character string
-    // cache already.
-    Label if_entryisundefined(this, Label::kDeferred),
-        if_entryisnotundefined(this);
-    Node* entry = LoadFixedArrayElementInt32Index(cache, code);
-    Branch(WordEqual(entry, UndefinedConstant()), &if_entryisundefined,
-           &if_entryisnotundefined);
-
-    Bind(&if_entryisundefined);
-    {
-      // Allocate a new SeqOneByteString for {code} and store it in the {cache}.
-      Node* result = AllocateSeqOneByteString(1);
-      StoreNoWriteBarrier(
-          MachineRepresentation::kWord8, result,
-          IntPtrConstant(SeqOneByteString::kHeaderSize - kHeapObjectTag), code);
-      StoreFixedArrayElementInt32Index(cache, code, result);
-      var_result.Bind(result);
-      Goto(&if_done);
-    }
-
-    Bind(&if_entryisnotundefined);
-    {
-      // Return the entry from the {cache}.
-      var_result.Bind(entry);
-      Goto(&if_done);
-    }
-  }
-
-  Bind(&if_codeistwobyte);
-  {
-    // Allocate a new SeqTwoByteString for {code}.
-    Node* result = AllocateSeqTwoByteString(1);
-    StoreNoWriteBarrier(
-        MachineRepresentation::kWord16, result,
-        IntPtrConstant(SeqTwoByteString::kHeaderSize - kHeapObjectTag), code);
-    var_result.Bind(result);
-    Goto(&if_done);
-  }
-
-  Bind(&if_done);
-  return var_result.value();
-}
-
-Node* CodeStubAssembler::TruncateFloat64ToInt32(Node* value) {
-  return raw_assembler_->TruncateFloat64ToInt32(TruncationMode::kJavaScript,
-                                                value);
-}
-
-void CodeStubAssembler::BranchIf(Node* condition, Label* if_true,
-                                 Label* if_false) {
-  Label if_condition_is_true(this), if_condition_is_false(this);
-  Branch(condition, &if_condition_is_true, &if_condition_is_false);
-  Bind(&if_condition_is_true);
-  Goto(if_true);
-  Bind(&if_condition_is_false);
-  Goto(if_false);
-}
-
-Node* CodeStubAssembler::CallN(CallDescriptor* descriptor, Node* code_target,
-                               Node** args) {
-  CallPrologue();
-  Node* return_value = raw_assembler_->CallN(descriptor, code_target, args);
-  CallEpilogue();
-  return return_value;
-}
-
-
-Node* CodeStubAssembler::TailCallN(CallDescriptor* descriptor,
-                                   Node* code_target, Node** args) {
-  return raw_assembler_->TailCallN(descriptor, code_target, args);
-}
-
-Node* CodeStubAssembler::CallRuntime(Runtime::FunctionId function_id,
-                                     Node* context) {
-  CallPrologue();
-  Node* return_value = raw_assembler_->CallRuntime0(function_id, context);
-  CallEpilogue();
-  return return_value;
-}
-
-Node* CodeStubAssembler::CallRuntime(Runtime::FunctionId function_id,
-                                     Node* context, Node* arg1) {
-  CallPrologue();
-  Node* return_value = raw_assembler_->CallRuntime1(function_id, arg1, context);
-  CallEpilogue();
-  return return_value;
-}
-
-Node* CodeStubAssembler::CallRuntime(Runtime::FunctionId function_id,
-                                     Node* context, Node* arg1, Node* arg2) {
-  CallPrologue();
-  Node* return_value =
-      raw_assembler_->CallRuntime2(function_id, arg1, arg2, context);
-  CallEpilogue();
-  return return_value;
-}
-
-Node* CodeStubAssembler::CallRuntime(Runtime::FunctionId function_id,
-                                     Node* context, Node* arg1, Node* arg2,
-                                     Node* arg3) {
-  CallPrologue();
-  Node* return_value =
-      raw_assembler_->CallRuntime3(function_id, arg1, arg2, arg3, context);
-  CallEpilogue();
-  return return_value;
-}
-
-Node* CodeStubAssembler::CallRuntime(Runtime::FunctionId function_id,
-                                     Node* context, Node* arg1, Node* arg2,
-                                     Node* arg3, Node* arg4) {
-  CallPrologue();
-  Node* return_value = raw_assembler_->CallRuntime4(function_id, arg1, arg2,
-                                                    arg3, arg4, context);
-  CallEpilogue();
-  return return_value;
-}
-
-Node* CodeStubAssembler::TailCallRuntime(Runtime::FunctionId function_id,
-                                         Node* context) {
-  return raw_assembler_->TailCallRuntime0(function_id, context);
-}
-
-Node* CodeStubAssembler::TailCallRuntime(Runtime::FunctionId function_id,
-                                         Node* context, Node* arg1) {
-  return raw_assembler_->TailCallRuntime1(function_id, arg1, context);
-}
-
-Node* CodeStubAssembler::TailCallRuntime(Runtime::FunctionId function_id,
-                                         Node* context, Node* arg1,
-                                         Node* arg2) {
-  return raw_assembler_->TailCallRuntime2(function_id, arg1, arg2, context);
-}
-
-Node* CodeStubAssembler::TailCallRuntime(Runtime::FunctionId function_id,
-                                         Node* context, Node* arg1, Node* arg2,
-                                         Node* arg3) {
-  return raw_assembler_->TailCallRuntime3(function_id, arg1, arg2, arg3,
-                                          context);
-}
-
-Node* CodeStubAssembler::TailCallRuntime(Runtime::FunctionId function_id,
-                                         Node* context, Node* arg1, Node* arg2,
-                                         Node* arg3, Node* arg4) {
-  return raw_assembler_->TailCallRuntime4(function_id, arg1, arg2, arg3, arg4,
-                                          context);
-}
-
-Node* CodeStubAssembler::CallStub(Callable const& callable, Node* context,
-                                  Node* arg1, size_t result_size) {
-  Node* target = HeapConstant(callable.code());
-  return CallStub(callable.descriptor(), target, context, arg1, result_size);
-}
-
-Node* CodeStubAssembler::CallStub(Callable const& callable, Node* context,
-                                  Node* arg1, Node* arg2, size_t result_size) {
-  Node* target = HeapConstant(callable.code());
-  return CallStub(callable.descriptor(), target, context, arg1, arg2,
-                  result_size);
-}
-
-Node* CodeStubAssembler::CallStub(Callable const& callable, Node* context,
-                                  Node* arg1, Node* arg2, Node* arg3,
-                                  size_t result_size) {
-  Node* target = HeapConstant(callable.code());
-  return CallStub(callable.descriptor(), target, context, arg1, arg2, arg3,
-                  result_size);
-}
-
-Node* CodeStubAssembler::CallStub(const CallInterfaceDescriptor& descriptor,
-                                  Node* target, Node* context, Node* arg1,
-                                  size_t result_size) {
-  CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), descriptor, descriptor.GetStackParameterCount(),
-      CallDescriptor::kNoFlags, Operator::kNoProperties,
-      MachineType::AnyTagged(), result_size);
-
-  Node** args = zone()->NewArray<Node*>(2);
-  args[0] = arg1;
-  args[1] = context;
-
-  return CallN(call_descriptor, target, args);
-}
-
-Node* CodeStubAssembler::CallStub(const CallInterfaceDescriptor& descriptor,
-                                  Node* target, Node* context, Node* arg1,
-                                  Node* arg2, size_t result_size) {
-  CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), descriptor, descriptor.GetStackParameterCount(),
-      CallDescriptor::kNoFlags, Operator::kNoProperties,
-      MachineType::AnyTagged(), result_size);
-
-  Node** args = zone()->NewArray<Node*>(3);
-  args[0] = arg1;
-  args[1] = arg2;
-  args[2] = context;
-
-  return CallN(call_descriptor, target, args);
-}
-
-Node* CodeStubAssembler::CallStub(const CallInterfaceDescriptor& descriptor,
-                                  Node* target, Node* context, Node* arg1,
-                                  Node* arg2, Node* arg3, size_t result_size) {
-  CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), descriptor, descriptor.GetStackParameterCount(),
-      CallDescriptor::kNoFlags, Operator::kNoProperties,
-      MachineType::AnyTagged(), result_size);
-
-  Node** args = zone()->NewArray<Node*>(4);
-  args[0] = arg1;
-  args[1] = arg2;
-  args[2] = arg3;
-  args[3] = context;
-
-  return CallN(call_descriptor, target, args);
-}
-
-Node* CodeStubAssembler::CallStub(const CallInterfaceDescriptor& descriptor,
-                                  Node* target, Node* context, Node* arg1,
-                                  Node* arg2, Node* arg3, Node* arg4,
-                                  size_t result_size) {
-  CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), descriptor, descriptor.GetStackParameterCount(),
-      CallDescriptor::kNoFlags, Operator::kNoProperties,
-      MachineType::AnyTagged(), result_size);
-
-  Node** args = zone()->NewArray<Node*>(5);
-  args[0] = arg1;
-  args[1] = arg2;
-  args[2] = arg3;
-  args[3] = arg4;
-  args[4] = context;
-
-  return CallN(call_descriptor, target, args);
-}
-
-Node* CodeStubAssembler::CallStub(const CallInterfaceDescriptor& descriptor,
-                                  Node* target, Node* context, Node* arg1,
-                                  Node* arg2, Node* arg3, Node* arg4,
-                                  Node* arg5, size_t result_size) {
-  CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), descriptor, descriptor.GetStackParameterCount(),
-      CallDescriptor::kNoFlags, Operator::kNoProperties,
-      MachineType::AnyTagged(), result_size);
-
-  Node** args = zone()->NewArray<Node*>(6);
-  args[0] = arg1;
-  args[1] = arg2;
-  args[2] = arg3;
-  args[3] = arg4;
-  args[4] = arg5;
-  args[5] = context;
-
-  return CallN(call_descriptor, target, args);
-}
-
-Node* CodeStubAssembler::TailCallStub(Callable const& callable, Node* context,
-                                      Node* arg1, Node* arg2,
-                                      size_t result_size) {
-  Node* target = HeapConstant(callable.code());
-  return TailCallStub(callable.descriptor(), target, context, arg1, arg2,
-                      result_size);
-}
-
-Node* CodeStubAssembler::TailCallStub(const CallInterfaceDescriptor& descriptor,
-                                      Node* target, Node* context, Node* arg1,
-                                      Node* arg2, size_t result_size) {
-  CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), descriptor, descriptor.GetStackParameterCount(),
-      CallDescriptor::kSupportsTailCalls, Operator::kNoProperties,
-      MachineType::AnyTagged(), result_size);
-
-  Node** args = zone()->NewArray<Node*>(3);
-  args[0] = arg1;
-  args[1] = arg2;
-  args[2] = context;
-
-  return raw_assembler_->TailCallN(call_descriptor, target, args);
-}
-
-Node* CodeStubAssembler::TailCallBytecodeDispatch(
-    const CallInterfaceDescriptor& interface_descriptor,
-    Node* code_target_address, Node** args) {
-  CallDescriptor* descriptor = Linkage::GetBytecodeDispatchCallDescriptor(
-      isolate(), zone(), interface_descriptor,
-      interface_descriptor.GetStackParameterCount());
-  return raw_assembler_->TailCallN(descriptor, code_target_address, args);
-}
-
-void CodeStubAssembler::Goto(CodeStubAssembler::Label* label) {
-  label->MergeVariables();
-  raw_assembler_->Goto(label->label_);
-}
-
-void CodeStubAssembler::GotoIf(Node* condition, Label* true_label) {
-  Label false_label(this);
-  Branch(condition, true_label, &false_label);
-  Bind(&false_label);
-}
-
-void CodeStubAssembler::GotoUnless(Node* condition, Label* false_label) {
-  Label true_label(this);
-  Branch(condition, &true_label, false_label);
-  Bind(&true_label);
-}
-
-void CodeStubAssembler::Branch(Node* condition,
-                               CodeStubAssembler::Label* true_label,
-                               CodeStubAssembler::Label* false_label) {
-  true_label->MergeVariables();
-  false_label->MergeVariables();
-  return raw_assembler_->Branch(condition, true_label->label_,
-                                false_label->label_);
-}
-
-void CodeStubAssembler::Switch(Node* index, Label* default_label,
-                               int32_t* case_values, Label** case_labels,
-                               size_t case_count) {
-  RawMachineLabel** labels =
-      new (zone()->New(sizeof(RawMachineLabel*) * case_count))
-          RawMachineLabel*[case_count];
-  for (size_t i = 0; i < case_count; ++i) {
-    labels[i] = case_labels[i]->label_;
-    case_labels[i]->MergeVariables();
-    default_label->MergeVariables();
-  }
-  return raw_assembler_->Switch(index, default_label->label_, case_values,
-                                labels, case_count);
-}
-
-// RawMachineAssembler delegate helpers:
-Isolate* CodeStubAssembler::isolate() const {
-  return raw_assembler_->isolate();
-}
-
-Factory* CodeStubAssembler::factory() const { return isolate()->factory(); }
-
-Graph* CodeStubAssembler::graph() const { return raw_assembler_->graph(); }
-
-Zone* CodeStubAssembler::zone() const { return raw_assembler_->zone(); }
-
-// The core implementation of Variable is stored through an indirection so
-// that it can outlive the often block-scoped Variable declarations. This is
-// needed to ensure that variable binding and merging through phis can
-// properly be verified.
-class CodeStubAssembler::Variable::Impl : public ZoneObject {
- public:
-  explicit Impl(MachineRepresentation rep) : value_(nullptr), rep_(rep) {}
-  Node* value_;
-  MachineRepresentation rep_;
-};
-
-CodeStubAssembler::Variable::Variable(CodeStubAssembler* assembler,
-                                      MachineRepresentation rep)
-    : impl_(new (assembler->zone()) Impl(rep)) {
-  assembler->variables_.push_back(impl_);
-}
-
-void CodeStubAssembler::Variable::Bind(Node* value) { impl_->value_ = value; }
-
-Node* CodeStubAssembler::Variable::value() const {
-  DCHECK_NOT_NULL(impl_->value_);
-  return impl_->value_;
-}
-
-MachineRepresentation CodeStubAssembler::Variable::rep() const {
-  return impl_->rep_;
-}
-
-bool CodeStubAssembler::Variable::IsBound() const {
-  return impl_->value_ != nullptr;
-}
-
-CodeStubAssembler::Label::Label(CodeStubAssembler* assembler,
-                                int merged_value_count,
-                                CodeStubAssembler::Variable** merged_variables,
-                                CodeStubAssembler::Label::Type type)
-    : bound_(false), merge_count_(0), assembler_(assembler), label_(nullptr) {
-  void* buffer = assembler->zone()->New(sizeof(RawMachineLabel));
-  label_ = new (buffer)
-      RawMachineLabel(type == kDeferred ? RawMachineLabel::kDeferred
-                                        : RawMachineLabel::kNonDeferred);
-  for (int i = 0; i < merged_value_count; ++i) {
-    variable_phis_[merged_variables[i]->impl_] = nullptr;
-  }
-}
-
-void CodeStubAssembler::Label::MergeVariables() {
-  ++merge_count_;
-  for (auto var : assembler_->variables_) {
-    size_t count = 0;
-    Node* node = var->value_;
-    if (node != nullptr) {
-      auto i = variable_merges_.find(var);
-      if (i != variable_merges_.end()) {
-        i->second.push_back(node);
-        count = i->second.size();
-      } else {
-        count = 1;
-        variable_merges_[var] = std::vector<Node*>(1, node);
-      }
-    }
-    // If the following asserts, then you've jumped to a label without a bound
-    // variable along that path that expects to merge its value into a phi.
-    DCHECK(variable_phis_.find(var) == variable_phis_.end() ||
-           count == merge_count_);
-    USE(count);
-
-    // If the label is already bound, we already know the set of variables to
-    // merge and phi nodes have already been created.
-    if (bound_) {
-      auto phi = variable_phis_.find(var);
-      if (phi != variable_phis_.end()) {
-        DCHECK_NOT_NULL(phi->second);
-        assembler_->raw_assembler_->AppendPhiInput(phi->second, node);
-      } else {
-        auto i = variable_merges_.find(var);
-        if (i != variable_merges_.end()) {
-          // If the following assert fires, then you've declared a variable that
-          // has the same bound value along all paths up until the point you
-          // bound this label, but then later merged a path with a new value for
-          // the variable after the label bind (it's not possible to add phis to
-          // the bound label after the fact, just make sure to list the variable
-          // in the label's constructor's list of merged variables).
-          DCHECK(find_if(i->second.begin(), i->second.end(),
-                         [node](Node* e) -> bool { return node != e; }) ==
-                 i->second.end());
-        }
-      }
-    }
-  }
-}
-
-void CodeStubAssembler::Label::Bind() {
-  DCHECK(!bound_);
-  assembler_->raw_assembler_->Bind(label_);
-
-  // Make sure that all variables that have changed along any path up to this
-  // point are marked as merge variables.
-  for (auto var : assembler_->variables_) {
-    Node* shared_value = nullptr;
-    auto i = variable_merges_.find(var);
-    if (i != variable_merges_.end()) {
-      for (auto value : i->second) {
-        DCHECK(value != nullptr);
-        if (value != shared_value) {
-          if (shared_value == nullptr) {
-            shared_value = value;
-          } else {
-            variable_phis_[var] = nullptr;
-          }
-        }
-      }
-    }
-  }
-
-  for (auto var : variable_phis_) {
-    CodeStubAssembler::Variable::Impl* var_impl = var.first;
-    auto i = variable_merges_.find(var_impl);
-    // If the following assert fires, then a variable that has been marked as
-    // being merged at the label--either by explicitly marking it so in the
-    // label constructor or by having seen different bound values at branches
-    // into the label--doesn't have a bound value along all of the paths that
-    // have been merged into the label up to this point.
-    DCHECK(i != variable_merges_.end() && i->second.size() == merge_count_);
-    Node* phi = assembler_->raw_assembler_->Phi(
-        var.first->rep_, static_cast<int>(merge_count_), &(i->second[0]));
-    variable_phis_[var_impl] = phi;
-  }
-
-  // Bind all variables to a merge phi, the common value along all paths or
-  // null.
-  for (auto var : assembler_->variables_) {
-    auto i = variable_phis_.find(var);
-    if (i != variable_phis_.end()) {
-      var->value_ = i->second;
-    } else {
-      auto j = variable_merges_.find(var);
-      if (j != variable_merges_.end() && j->second.size() == merge_count_) {
-        var->value_ = j->second.back();
-      } else {
-        var->value_ = nullptr;
-      }
-    }
-  }
-
-  bound_ = true;
-}
-
-}  // namespace compiler
-}  // namespace internal
-}  // namespace v8