[Interpreter] Add implementations of arithmetic binary op bytecodes.

src/interpreter/interpreter.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_INTERPRETER_H_
 #define V8_INTERPRETER_INTERPRETER_H_
 
 // Clients of this interface shouldn't depend on lots of interpreter internals.
 // Do not include anything from src/interpreter other than
 // src/interpreter/bytecodes.h here!
 #include "src/base/macros.h"
+#include "src/builtins.h"
 #include "src/interpreter/bytecodes.h"
 
 namespace v8 {
 namespace internal {
 
 class Isolate;
 class CompilationInfo;
 
 namespace compiler {
 class InterpreterAssembler;
@@ skipping 17 matching lines @@
   // Generate bytecode for |info|.
   static bool MakeBytecode(CompilationInfo* info);
 
  private:
 // Bytecode handler generator functions.
 #define DECLARE_BYTECODE_HANDLER_GENERATOR(Name, ...) \
   void Do##Name(compiler::InterpreterAssembler* assembler);
   BYTECODE_LIST(DECLARE_BYTECODE_HANDLER_GENERATOR)
 #undef DECLARE_BYTECODE_HANDLER_GENERATOR
 
+  // Generates code to perform the binary operations via |binop_builtin|.
+  void DoBinaryOp(Builtins::JavaScript binop_builtin,
+                  compiler::InterpreterAssembler* assembler);
+
   bool IsInterpreterTableInitialized(Handle<FixedArray> handler_table);
 
   Isolate* isolate_;
 
   DISALLOW_COPY_AND_ASSIGN(Interpreter);
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_INTERPRETER_H_