[Interpreter] Optimize the Register Optimizer.

test/unittests/interpreter/bytecode-dead-code-optimizer-unittest.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/interpreter/bytecode-dead-code-optimizer.h"
 #include "src/interpreter/bytecode-label.h"
 #include "src/objects.h"
 #include "test/unittests/test-utils.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
 class BytecodeDeadCodeOptimizerTest : public BytecodePipelineStage,
                                       public TestWithIsolateAndZone {
  public:
   BytecodeDeadCodeOptimizerTest()
       : dead_code_optimizer_(this), last_written_(Bytecode::kIllegal) {}
   ~BytecodeDeadCodeOptimizerTest() override {}
 
   void Write(BytecodeNode* node) override {
     write_count_++;
-    last_written_.Clone(node);
+    last_written_ = *node;
   }
 
   void WriteJump(BytecodeNode* node, BytecodeLabel* label) override {
     write_count_++;
-    last_written_.Clone(node);
+    last_written_ = *node;
   }
 
   void BindLabel(BytecodeLabel* label) override {}
   void BindLabel(const BytecodeLabel& target, BytecodeLabel* label) override {}
   Handle<BytecodeArray> ToBytecodeArray(
       Isolate* isolate, int fixed_register_count, int parameter_count,
       Handle<FixedArray> handle_table) override {
     return Handle<BytecodeArray>();
   }
 
   BytecodeDeadCodeOptimizer* optimizer() { return &dead_code_optimizer_; }
 
   int write_count() const { return write_count_; }
   const BytecodeNode& last_written() const { return last_written_; }
 
  private:
   BytecodeDeadCodeOptimizer dead_code_optimizer_;
 
   int write_count_ = 0;
   BytecodeNode last_written_;
 };
 
 TEST_F(BytecodeDeadCodeOptimizerTest, LiveCodeKept) {
   BytecodeNode add(Bytecode::kAdd, Register(0).ToOperand(), 1);
   optimizer()->Write(&add);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(add, last_written());
 
   BytecodeLabel target;
-  BytecodeNode jump(Bytecode::kJump, 0, nullptr);
+  BytecodeNode jump(Bytecode::kJump, 0);
   optimizer()->WriteJump(&jump, &target);
   CHECK_EQ(write_count(), 2);
   CHECK_EQ(jump, last_written());
 }
 
 TEST_F(BytecodeDeadCodeOptimizerTest, DeadCodeAfterReturnEliminated) {
   BytecodeNode ret(Bytecode::kReturn);
   optimizer()->Write(&ret);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(ret, last_written());
@@ skipping 23 matching lines @@
   CHECK_EQ(rethrow, last_written());
 
   BytecodeNode add(Bytecode::kAdd, Register(0).ToOperand(), 1);
   optimizer()->Write(&add);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(rethrow, last_written());
 }
 
 TEST_F(BytecodeDeadCodeOptimizerTest, DeadCodeAfterJumpEliminated) {
   BytecodeLabel target;
-  BytecodeNode jump(Bytecode::kJump, 0, nullptr);
+  BytecodeNode jump(Bytecode::kJump, 0);
   optimizer()->WriteJump(&jump, &target);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(jump, last_written());
 
   BytecodeNode add(Bytecode::kAdd, Register(0).ToOperand(), 1);
   optimizer()->Write(&add);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(jump, last_written());
 }
 
 TEST_F(BytecodeDeadCodeOptimizerTest, DeadCodeStillDeadAfterConditinalJump) {
   BytecodeNode ret(Bytecode::kReturn);
   optimizer()->Write(&ret);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(ret, last_written());
 
   BytecodeLabel target;
-  BytecodeNode jump(Bytecode::kJumpIfTrue, 0, nullptr);
+  BytecodeNode jump(Bytecode::kJumpIfTrue, 0);
   optimizer()->WriteJump(&jump, &target);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(ret, last_written());
 
   BytecodeNode add(Bytecode::kAdd, Register(0).ToOperand(), 1);
   optimizer()->Write(&add);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(ret, last_written());
 }
 
 TEST_F(BytecodeDeadCodeOptimizerTest, CodeLiveAfterLabelBind) {
   BytecodeNode ret(Bytecode::kReturn);
   optimizer()->Write(&ret);
   CHECK_EQ(write_count(), 1);
   CHECK_EQ(ret, last_written());
 
   BytecodeLabel target;
   optimizer()->BindLabel(&target);
 
   BytecodeNode add(Bytecode::kAdd, Register(0).ToOperand(), 1);
   optimizer()->Write(&add);
   CHECK_EQ(write_count(), 2);
   CHECK_EQ(add, last_written());
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8