Remove the first_right_arg hack for HMod.

src/hydrogen-instructions.h

 // Copyright 2012 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 4883 matching lines @@
     SetFlag(kCanOverflow);
   }
 };
 
 
 class HMod V8_FINAL : public HArithmeticBinaryOperation {
  public:
   static HInstruction* New(Zone* zone,
                            HValue* context,
                            HValue* left,
-                           HValue* right,
-                           Maybe<int> fixed_right_arg);
-
-  Maybe<int> fixed_right_arg() const { return fixed_right_arg_; }
+                           HValue* right);
 
   bool HasPowerOf2Divisor() {
     if (right()->IsConstant() &&
         HConstant::cast(right())->HasInteger32Value()) {
       int32_t value = HConstant::cast(right())->Integer32Value();
       return value != 0 && (IsPowerOf2(value) || IsPowerOf2(-value));
     }
 
     return false;
   }
@@ skipping 13 matching lines @@
   DECLARE_CONCRETE_INSTRUCTION(Mod)
 
  protected:
   virtual bool DataEquals(HValue* other) V8_OVERRIDE { return true; }
 
   virtual Range* InferRange(Zone* zone) V8_OVERRIDE;
 
  private:
   HMod(HValue* context,
        HValue* left,
-       HValue* right,
-       Maybe<int> fixed_right_arg)
-      : HArithmeticBinaryOperation(context, left, right),
-        fixed_right_arg_(fixed_right_arg) {
+       HValue* right) : HArithmeticBinaryOperation(context, left, right) {
     SetFlag(kCanBeDivByZero);
     SetFlag(kCanOverflow);
   }
-
-  const Maybe<int> fixed_right_arg_;
 };
 
 
 class HDiv V8_FINAL : public HArithmeticBinaryOperation {
  public:
   static HInstruction* New(Zone* zone,
                            HValue* context,
                            HValue* left,
                            HValue* right);
 
@@ skipping 2498 matching lines @@
   virtual bool IsDeletable() const V8_OVERRIDE { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_