else if (addr instanceof OPT_ConstantOperand) { VM._assert(false); }
  static OPT_Operand asRegAddress(OPT_Operand addr,                           OPT_Instruction s,                           OPT_IR ir) {    if (addr instanceof OPT_AddressConstantOperand) {      OPT_RegisterOperand rop = ir.regpool.makeTempAddress();      s.insertBefore(Move.create(REF_MOVE, rop, addr));      return rop.copyD2U();    }    // Operand was OK as is.    return addr;  }