diff --git a/test/unittests/compiler/instruction-sequence-unittest.cc b/test/unittests/compiler/instruction-sequence-unittest.cc
new file mode 100644
index 0000000..9546376
--- /dev/null
+++ b/test/unittests/compiler/instruction-sequence-unittest.cc
@@ -0,0 +1,475 @@
+// Copyright 2014 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/base/utils/random-number-generator.h"
+#include "src/compiler/pipeline.h"
+#include "test/unittests/compiler/instruction-sequence-unittest.h"
+#include "test/unittests/test-utils.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+static const char*
+    general_register_names_[RegisterConfiguration::kMaxGeneralRegisters];
+static const char*
+    double_register_names_[RegisterConfiguration::kMaxDoubleRegisters];
+static char register_names_[10 * (RegisterConfiguration::kMaxGeneralRegisters +
+                                  RegisterConfiguration::kMaxDoubleRegisters)];
+
+
+static void InitializeRegisterNames() {
+  char* loc = register_names_;
+  for (int i = 0; i < RegisterConfiguration::kMaxGeneralRegisters; ++i) {
+    general_register_names_[i] = loc;
+    loc += base::OS::SNPrintF(loc, 100, "gp_%d", i);
+    *loc++ = 0;
+  }
+  for (int i = 0; i < RegisterConfiguration::kMaxDoubleRegisters; ++i) {
+    double_register_names_[i] = loc;
+    loc += base::OS::SNPrintF(loc, 100, "fp_%d", i) + 1;
+    *loc++ = 0;
+  }
+}
+
+
+InstructionSequenceTest::InstructionSequenceTest()
+    : sequence_(nullptr),
+      num_general_registers_(kDefaultNRegs),
+      num_double_registers_(kDefaultNRegs),
+      instruction_blocks_(zone()),
+      current_instruction_index_(-1),
+      current_block_(nullptr),
+      block_returns_(false) {
+  InitializeRegisterNames();
+}
+
+
+void InstructionSequenceTest::SetNumRegs(int num_general_registers,
+                                         int num_double_registers) {
+  CHECK(config_.is_empty());
+  CHECK(instructions_.empty());
+  CHECK(instruction_blocks_.empty());
+  num_general_registers_ = num_general_registers;
+  num_double_registers_ = num_double_registers;
+}
+
+
+RegisterConfiguration* InstructionSequenceTest::config() {
+  if (config_.is_empty()) {
+    config_.Reset(new RegisterConfiguration(
+        num_general_registers_, num_double_registers_, num_double_registers_,
+        general_register_names_, double_register_names_));
+  }
+  return config_.get();
+}
+
+
+InstructionSequence* InstructionSequenceTest::sequence() {
+  if (sequence_ == nullptr) {
+    sequence_ = new (zone()) InstructionSequence(zone(), &instruction_blocks_);
+  }
+  return sequence_;
+}
+
+
+void InstructionSequenceTest::StartLoop(int loop_blocks) {
+  CHECK(current_block_ == nullptr);
+  if (!loop_blocks_.empty()) {
+    CHECK(!loop_blocks_.back().loop_header_.IsValid());
+  }
+  LoopData loop_data = {Rpo::Invalid(), loop_blocks};
+  loop_blocks_.push_back(loop_data);
+}
+
+
+void InstructionSequenceTest::EndLoop() {
+  CHECK(current_block_ == nullptr);
+  CHECK(!loop_blocks_.empty());
+  CHECK_EQ(0, loop_blocks_.back().expected_blocks_);
+  loop_blocks_.pop_back();
+}
+
+
+void InstructionSequenceTest::StartBlock() {
+  block_returns_ = false;
+  NewBlock();
+}
+
+
+int InstructionSequenceTest::EndBlock(BlockCompletion completion) {
+  int instruction_index = kMinInt;
+  if (block_returns_) {
+    CHECK(completion.type_ == kBlockEnd || completion.type_ == kFallThrough);
+    completion.type_ = kBlockEnd;
+  }
+  switch (completion.type_) {
+    case kBlockEnd:
+      break;
+    case kFallThrough:
+      instruction_index = EmitFallThrough();
+      break;
+    case kJump:
+      CHECK(!block_returns_);
+      instruction_index = EmitJump();
+      break;
+    case kBranch:
+      CHECK(!block_returns_);
+      instruction_index = EmitBranch(completion.op_);
+      break;
+  }
+  completions_.push_back(completion);
+  CHECK(current_block_ != nullptr);
+  sequence()->EndBlock(current_block_->rpo_number());
+  current_block_ = nullptr;
+  return instruction_index;
+}
+
+
+InstructionSequenceTest::TestOperand InstructionSequenceTest::Imm(int32_t imm) {
+  int index = sequence()->AddImmediate(Constant(imm));
+  return TestOperand(kImmediate, index);
+}
+
+
+InstructionSequenceTest::VReg InstructionSequenceTest::Define(
+    TestOperand output_op) {
+  VReg vreg = NewReg();
+  InstructionOperand* outputs[1]{ConvertOutputOp(vreg, output_op)};
+  Emit(vreg.value_, kArchNop, 1, outputs);
+  return vreg;
+}
+
+
+int InstructionSequenceTest::Return(TestOperand input_op_0) {
+  block_returns_ = true;
+  InstructionOperand* inputs[1]{ConvertInputOp(input_op_0)};
+  return Emit(NewIndex(), kArchRet, 0, nullptr, 1, inputs);
+}
+
+
+PhiInstruction* InstructionSequenceTest::Phi(VReg incoming_vreg_0,
+                                             VReg incoming_vreg_1,
+                                             VReg incoming_vreg_2,
+                                             VReg incoming_vreg_3) {
+  auto phi = new (zone()) PhiInstruction(zone(), NewReg().value_, 10);
+  VReg inputs[] = {incoming_vreg_0, incoming_vreg_1, incoming_vreg_2,
+                   incoming_vreg_3};
+  for (size_t i = 0; i < arraysize(inputs); ++i) {
+    if (inputs[i].value_ == kNoValue) break;
+    Extend(phi, inputs[i]);
+  }
+  current_block_->AddPhi(phi);
+  return phi;
+}
+
+
+void InstructionSequenceTest::Extend(PhiInstruction* phi, VReg vreg) {
+  phi->Extend(zone(), vreg.value_);
+}
+
+
+InstructionSequenceTest::VReg InstructionSequenceTest::DefineConstant(
+    int32_t imm) {
+  VReg vreg = NewReg();
+  sequence()->AddConstant(vreg.value_, Constant(imm));
+  InstructionOperand* outputs[1]{ConstantOperand::Create(vreg.value_, zone())};
+  Emit(vreg.value_, kArchNop, 1, outputs);
+  return vreg;
+}
+
+
+int InstructionSequenceTest::EmitNop() { return Emit(NewIndex(), kArchNop); }
+
+
+static size_t CountInputs(size_t size,
+                          InstructionSequenceTest::TestOperand* inputs) {
+  size_t i = 0;
+  for (; i < size; ++i) {
+    if (inputs[i].type_ == InstructionSequenceTest::kInvalid) break;
+  }
+  return i;
+}
+
+
+int InstructionSequenceTest::EmitI(size_t input_size, TestOperand* inputs) {
+  InstructionOperand** mapped_inputs = ConvertInputs(input_size, inputs);
+  return Emit(NewIndex(), kArchNop, 0, nullptr, input_size, mapped_inputs);
+}
+
+
+int InstructionSequenceTest::EmitI(TestOperand input_op_0,
+                                   TestOperand input_op_1,
+                                   TestOperand input_op_2,
+                                   TestOperand input_op_3) {
+  TestOperand inputs[] = {input_op_0, input_op_1, input_op_2, input_op_3};
+  return EmitI(CountInputs(arraysize(inputs), inputs), inputs);
+}
+
+
+InstructionSequenceTest::VReg InstructionSequenceTest::EmitOI(
+    TestOperand output_op, size_t input_size, TestOperand* inputs) {
+  VReg output_vreg = NewReg();
+  InstructionOperand* outputs[1]{ConvertOutputOp(output_vreg, output_op)};
+  InstructionOperand** mapped_inputs = ConvertInputs(input_size, inputs);
+  Emit(output_vreg.value_, kArchNop, 1, outputs, input_size, mapped_inputs);
+  return output_vreg;
+}
+
+
+InstructionSequenceTest::VReg InstructionSequenceTest::EmitOI(
+    TestOperand output_op, TestOperand input_op_0, TestOperand input_op_1,
+    TestOperand input_op_2, TestOperand input_op_3) {
+  TestOperand inputs[] = {input_op_0, input_op_1, input_op_2, input_op_3};
+  return EmitOI(output_op, CountInputs(arraysize(inputs), inputs), inputs);
+}
+
+
+InstructionSequenceTest::VReg InstructionSequenceTest::EmitCall(
+    TestOperand output_op, size_t input_size, TestOperand* inputs) {
+  VReg output_vreg = NewReg();
+  InstructionOperand* outputs[1]{ConvertOutputOp(output_vreg, output_op)};
+  CHECK(UnallocatedOperand::cast(outputs[0])->HasFixedPolicy());
+  InstructionOperand** mapped_inputs = ConvertInputs(input_size, inputs);
+  Emit(output_vreg.value_, kArchCallCodeObject, 1, outputs, input_size,
+       mapped_inputs, 0, nullptr, true);
+  return output_vreg;
+}
+
+
+InstructionSequenceTest::VReg InstructionSequenceTest::EmitCall(
+    TestOperand output_op, TestOperand input_op_0, TestOperand input_op_1,
+    TestOperand input_op_2, TestOperand input_op_3) {
+  TestOperand inputs[] = {input_op_0, input_op_1, input_op_2, input_op_3};
+  return EmitCall(output_op, CountInputs(arraysize(inputs), inputs), inputs);
+}
+
+
+const Instruction* InstructionSequenceTest::GetInstruction(
+    int instruction_index) {
+  auto it = instructions_.find(instruction_index);
+  CHECK(it != instructions_.end());
+  return it->second;
+}
+
+
+int InstructionSequenceTest::EmitBranch(TestOperand input_op) {
+  InstructionOperand* inputs[4]{ConvertInputOp(input_op), ConvertInputOp(Imm()),
+                                ConvertInputOp(Imm()), ConvertInputOp(Imm())};
+  InstructionCode opcode = kArchJmp | FlagsModeField::encode(kFlags_branch) |
+                           FlagsConditionField::encode(kEqual);
+  auto instruction =
+      NewInstruction(opcode, 0, nullptr, 4, inputs)->MarkAsControl();
+  return AddInstruction(NewIndex(), instruction);
+}
+
+
+int InstructionSequenceTest::EmitFallThrough() {
+  auto instruction = NewInstruction(kArchNop, 0, nullptr)->MarkAsControl();
+  return AddInstruction(NewIndex(), instruction);
+}
+
+
+int InstructionSequenceTest::EmitJump() {
+  InstructionOperand* inputs[1]{ConvertInputOp(Imm())};
+  auto instruction =
+      NewInstruction(kArchJmp, 0, nullptr, 1, inputs)->MarkAsControl();
+  return AddInstruction(NewIndex(), instruction);
+}
+
+
+Instruction* InstructionSequenceTest::NewInstruction(
+    InstructionCode code, size_t outputs_size, InstructionOperand** outputs,
+    size_t inputs_size, InstructionOperand** inputs, size_t temps_size,
+    InstructionOperand** temps) {
+  CHECK_NE(nullptr, current_block_);
+  return Instruction::New(zone(), code, outputs_size, outputs, inputs_size,
+                          inputs, temps_size, temps);
+}
+
+
+InstructionOperand* InstructionSequenceTest::Unallocated(
+    TestOperand op, UnallocatedOperand::ExtendedPolicy policy) {
+  auto unallocated = new (zone()) UnallocatedOperand(policy);
+  unallocated->set_virtual_register(op.vreg_.value_);
+  return unallocated;
+}
+
+
+InstructionOperand* InstructionSequenceTest::Unallocated(
+    TestOperand op, UnallocatedOperand::ExtendedPolicy policy,
+    UnallocatedOperand::Lifetime lifetime) {
+  auto unallocated = new (zone()) UnallocatedOperand(policy, lifetime);
+  unallocated->set_virtual_register(op.vreg_.value_);
+  return unallocated;
+}
+
+
+InstructionOperand* InstructionSequenceTest::Unallocated(
+    TestOperand op, UnallocatedOperand::ExtendedPolicy policy, int index) {
+  auto unallocated = new (zone()) UnallocatedOperand(policy, index);
+  unallocated->set_virtual_register(op.vreg_.value_);
+  return unallocated;
+}
+
+
+InstructionOperand* InstructionSequenceTest::Unallocated(
+    TestOperand op, UnallocatedOperand::BasicPolicy policy, int index) {
+  auto unallocated = new (zone()) UnallocatedOperand(policy, index);
+  unallocated->set_virtual_register(op.vreg_.value_);
+  return unallocated;
+}
+
+
+InstructionOperand** InstructionSequenceTest::ConvertInputs(
+    size_t input_size, TestOperand* inputs) {
+  InstructionOperand** mapped_inputs =
+      zone()->NewArray<InstructionOperand*>(static_cast<int>(input_size));
+  for (size_t i = 0; i < input_size; ++i) {
+    mapped_inputs[i] = ConvertInputOp(inputs[i]);
+  }
+  return mapped_inputs;
+}
+
+
+InstructionOperand* InstructionSequenceTest::ConvertInputOp(TestOperand op) {
+  if (op.type_ == kImmediate) {
+    CHECK_EQ(op.vreg_.value_, kNoValue);
+    return ImmediateOperand::Create(op.value_, zone());
+  }
+  CHECK_NE(op.vreg_.value_, kNoValue);
+  switch (op.type_) {
+    case kNone:
+      return Unallocated(op, UnallocatedOperand::NONE,
+                         UnallocatedOperand::USED_AT_START);
+    case kUnique:
+      return Unallocated(op, UnallocatedOperand::NONE);
+    case kUniqueRegister:
+      return Unallocated(op, UnallocatedOperand::MUST_HAVE_REGISTER);
+    case kRegister:
+      return Unallocated(op, UnallocatedOperand::MUST_HAVE_REGISTER,
+                         UnallocatedOperand::USED_AT_START);
+    case kFixedRegister:
+      CHECK(0 <= op.value_ && op.value_ < num_general_registers_);
+      return Unallocated(op, UnallocatedOperand::FIXED_REGISTER, op.value_);
+    case kFixedSlot:
+      return Unallocated(op, UnallocatedOperand::FIXED_SLOT, op.value_);
+    default:
+      break;
+  }
+  CHECK(false);
+  return NULL;
+}
+
+
+InstructionOperand* InstructionSequenceTest::ConvertOutputOp(VReg vreg,
+                                                             TestOperand op) {
+  CHECK_EQ(op.vreg_.value_, kNoValue);
+  op.vreg_ = vreg;
+  switch (op.type_) {
+    case kSameAsFirst:
+      return Unallocated(op, UnallocatedOperand::SAME_AS_FIRST_INPUT);
+    case kRegister:
+      return Unallocated(op, UnallocatedOperand::MUST_HAVE_REGISTER);
+    case kFixedSlot:
+      return Unallocated(op, UnallocatedOperand::FIXED_SLOT, op.value_);
+    case kFixedRegister:
+      CHECK(0 <= op.value_ && op.value_ < num_general_registers_);
+      return Unallocated(op, UnallocatedOperand::FIXED_REGISTER, op.value_);
+    default:
+      break;
+  }
+  CHECK(false);
+  return NULL;
+}
+
+
+InstructionBlock* InstructionSequenceTest::NewBlock() {
+  CHECK(current_block_ == nullptr);
+  auto block_id = BasicBlock::Id::FromSize(instruction_blocks_.size());
+  Rpo rpo = Rpo::FromInt(block_id.ToInt());
+  Rpo loop_header = Rpo::Invalid();
+  Rpo loop_end = Rpo::Invalid();
+  if (!loop_blocks_.empty()) {
+    auto& loop_data = loop_blocks_.back();
+    // This is a loop header.
+    if (!loop_data.loop_header_.IsValid()) {
+      loop_end = Rpo::FromInt(block_id.ToInt() + loop_data.expected_blocks_);
+      loop_data.expected_blocks_--;
+      loop_data.loop_header_ = rpo;
+    } else {
+      // This is a loop body.
+      CHECK_NE(0, loop_data.expected_blocks_);
+      // TODO(dcarney): handle nested loops.
+      loop_data.expected_blocks_--;
+      loop_header = loop_data.loop_header_;
+    }
+  }
+  // Construct instruction block.
+  auto instruction_block = new (zone())
+      InstructionBlock(zone(), block_id, rpo, loop_header, loop_end, false);
+  instruction_blocks_.push_back(instruction_block);
+  current_block_ = instruction_block;
+  sequence()->StartBlock(rpo);
+  return instruction_block;
+}
+
+
+void InstructionSequenceTest::WireBlocks() {
+  CHECK_EQ(nullptr, current_block());
+  CHECK(instruction_blocks_.size() == completions_.size());
+  size_t offset = 0;
+  for (const auto& completion : completions_) {
+    switch (completion.type_) {
+      case kBlockEnd:
+        break;
+      case kFallThrough:  // Fallthrough.
+      case kJump:
+        WireBlock(offset, completion.offset_0_);
+        break;
+      case kBranch:
+        WireBlock(offset, completion.offset_0_);
+        WireBlock(offset, completion.offset_1_);
+        break;
+    }
+    ++offset;
+  }
+}
+
+
+void InstructionSequenceTest::WireBlock(size_t block_offset, int jump_offset) {
+  size_t target_block_offset = block_offset + static_cast<size_t>(jump_offset);
+  CHECK(block_offset < instruction_blocks_.size());
+  CHECK(target_block_offset < instruction_blocks_.size());
+  auto block = instruction_blocks_[block_offset];
+  auto target = instruction_blocks_[target_block_offset];
+  block->successors().push_back(target->rpo_number());
+  target->predecessors().push_back(block->rpo_number());
+}
+
+
+int InstructionSequenceTest::Emit(int instruction_index, InstructionCode code,
+                                  size_t outputs_size,
+                                  InstructionOperand** outputs,
+                                  size_t inputs_size,
+                                  InstructionOperand** inputs,
+                                  size_t temps_size, InstructionOperand** temps,
+                                  bool is_call) {
+  auto instruction = NewInstruction(code, outputs_size, outputs, inputs_size,
+                                    inputs, temps_size, temps);
+  if (is_call) instruction->MarkAsCall();
+  return AddInstruction(instruction_index, instruction);
+}
+
+
+int InstructionSequenceTest::AddInstruction(int instruction_index,
+                                            Instruction* instruction) {
+  sequence()->AddInstruction(instruction);
+  return instruction_index;
+}
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8