[Interpreter] Move BytecodeHasHandler() from Interpreter to Bytecodes.

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 494 matching lines @@
 
   // Decodes an unsigned operand in a byte array.
   static uint32_t DecodeUnsignedOperand(const uint8_t* operand_start,
                                         OperandType operand_type,
                                         OperandScale operand_scale);
 
   // Decode a single bytecode and operands to |os|.
   static std::ostream& Decode(std::ostream& os, const uint8_t* bytecode_start,
                               int number_of_parameters);
 
+  // Returns true if a handler is generated for a bytecode at a given

[oth, 2016/03/24 15:50:35]

Could we also say something like "All bytecodes have handlers at
OperandScale::kSingle, but only bytecodes with scalable operands have handlers
with larger OperandScale values."

[Stefano Sanfilippo, 2016/03/24 16:07:14]

Done.

+  // operand scale.
+  static bool BytecodeHasHandler(Bytecode bytecode, OperandScale operand_scale);
+
   // Return the next larger operand scale.
   static OperandScale NextOperandScale(OperandScale operand_scale);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(Bytecodes);
 };
 
 std::ostream& operator<<(std::ostream& os, const Bytecode& bytecode);
 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_