[Interpreter] Preserve source positions in peephole optimizer.

src/interpreter/bytecodes.h

 // 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.
 
 #ifndef V8_INTERPRETER_BYTECODES_H_
 #define V8_INTERPRETER_BYTECODES_H_
 
 #include <iosfwd>
 
 // Clients of this interface shouldn't depend on lots of interpreter internals.
@@ skipping 547 matching lines @@
 
   // Returns true if the bytecode is Ldar or Star.
   static bool IsLdarOrStar(Bytecode bytecode);
 
   // Returns true if the bytecode has wider operand forms.
   static bool IsBytecodeWithScalableOperands(Bytecode bytecode);
 
   // Returns true if the bytecode is a scaling prefix bytecode.
   static bool IsPrefixScalingBytecode(Bytecode bytecode);
 
+  // Returns true if the bytecode has no effects outside the current
+  // interpreter frame.
+  static bool IsWithoutExternalSideEffects(Bytecode bytecode);
+
   // Returns true if |operand_type| is any type of register operand.
   static bool IsRegisterOperandType(OperandType operand_type);
 
   // Returns true if |operand_type| represents a register used as an input.
   static bool IsRegisterInputOperandType(OperandType operand_type);
 
   // Returns true if |operand_type| represents a register used as an output.
   static bool IsRegisterOutputOperandType(OperandType operand_type);
 
   // Returns the number of registers represented by a register operand. For
@@ skipping 67 matching lines @@
 std::ostream& operator<<(std::ostream& os, const AccumulatorUse& use);
 std::ostream& operator<<(std::ostream& os, const OperandScale& operand_scale);
 std::ostream& operator<<(std::ostream& os, const OperandSize& operand_size);
 std::ostream& operator<<(std::ostream& os, const OperandType& operand_type);
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_BYTECODES_H_