[Interpreter]: Add kRegList operand type for register list operands.

src/interpreter/bytecode-register-optimizer.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/interpreter/bytecode-register-optimizer.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
@@ skipping 515 matching lines @@
   //
   // For each output register about to be clobbered, materialize an
   // equivalent if it exists. Put each register in it's own equivalence set.
   //
   const uint32_t* operands = node->operands();
   int operand_count = node->operand_count();
   const OperandType* operand_types =
       Bytecodes::GetOperandTypes(node->bytecode());
   for (int i = 0; i < operand_count; ++i) {
     int count;
-    // operand_types is terminated by OperandType::kNone so this does not
-    // go out of bounds.
-    if (operand_types[i + 1] == OperandType::kRegCount) {
+    if (operand_types[i] == OperandType::kRegList) {
+      DCHECK_LT(i, operand_count - 1);
+      DCHECK(operand_types[i + 1] == OperandType::kRegCount);
       count = static_cast<int>(operands[i + 1]);
     } else {
       count = Bytecodes::GetNumberOfRegistersRepresentedBy(operand_types[i]);
     }
 
     if (count == 0) {
       continue;
     }
 
     Register reg = Register::FromOperand(static_cast<int32_t>(operands[i]));
@@ skipping 103 matching lines @@
 void BytecodeRegisterOptimizer::RegisterListFreeEvent(RegisterList reg_list) {
   int first_index = reg_list.first_register().index();
   for (int i = 0; i < reg_list.register_count(); i++) {
     GetRegisterInfo(Register(first_index + i))->set_allocated(false);
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8