return REDUCED;
return DefUseEffect.REDUCED;
  private static byte longXor(OPT_Instruction s) {   if (CF_LONG) {      canonicalizeCommutativeOperator(s);      OPT_Operand op1 = Binary.getVal1(s);      OPT_Operand op2 = Binary.getVal2(s);      if (op1.similar(op2)) {        // THE SAME OPERAND: x ^ x == 0        Move.mutate(s, LONG_MOVE, Binary.getClearResult(s),                     LC(0));        return MOVE_FOLDED;      }      if (op2.isLongConstant()) {        long val2 = op2.asLongConstant().value;        if (op1.isLongConstant()) {          // BOTH CONSTANTS: FOLD          long val1 = op1.asLongConstant().value;          Move.mutate(s, LONG_MOVE, Binary.getClearResult(s),                       LC(val1 ^ val2));          return MOVE_FOLDED;        } else {          // ONLY OP2 IS CONSTANT: ATTEMPT TO APPLY AXIOMS          if (val2 == -1L) {                // x ^ -1L == x ^ 0xff..ff = ~x            Unary.mutate(s, LONG_NOT, Binary.getClearResult(s),                          Binary.getClearVal1(s));            return REDUCED;          }          if (val2 == 0L) {                 // x ^ 0L == x            Move.mutate(s, LONG_MOVE, Binary.getClearResult(s),                         Binary.getClearVal1(s));            return MOVE_REDUCED;          }        }      }    }    return UNCHANGED;  }