Small cleanup of unused code in hydrogen IR.

src/hydrogen-instructions.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 593 matching lines @@
 
   virtual const char* Mnemonic() const = 0;
   virtual Opcode opcode() const = 0;
 
   // Updated the inferred type of this instruction and returns true if
   // it has changed.
   bool UpdateInferredType();
 
   virtual HType CalculateInferredType() const;
 
-  // Helper for type conversions used by normal and phi instructions.
-  void InsertInputConversion(HInstruction* previous, int index, HType type);
-
 #ifdef DEBUG
   virtual void Verify() = 0;
 #endif
 
  protected:
   // This function must be overridden for instructions with flag kUseGVN, to
   // compare the non-Operand parts of the instruction.
   virtual bool DataEquals(HValue* other) const {
     UNREACHABLE();
     return false;
@@ skipping 2790 matching lines @@
   HValue* object() const { return left(); }
   HValue* key() const { return right(); }
 };
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_