yosys/techlibs/xilinx/abc9_model.v

/*
 *  yosys -- Yosys Open SYnthesis Suite
 *
 *  Copyright (C) 2012  Claire Xenia Wolf <claire@yosyshq.com>
 *                2019  Eddie Hung    <eddie@fpgeh.com>
 *
 *  Permission to use, copy, modify, and/or distribute this software for any
 *  purpose with or without fee is hereby granted, provided that the above
 *  copyright notice and this permission notice appear in all copies.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

// ============================================================================

// Box containing MUXF7.[AB] + MUXF8,
//   Necessary to make these an atomic unit so that
//   ABC cannot optimise just one of the MUXF7 away
//   and expect to save on its delay
(* abc9_box, lib_whitebox *)
module \$__XILINX_MUXF78 (output O, input I0, I1, I2, I3, S0, S1);
  assign O = S1 ? (S0 ? I3 : I2)
                : (S0 ? I1 : I0);
  specify
    (I0 => O) = 294;
    (I1 => O) = 297;
    (I2 => O) = 311;
    (I3 => O) = 317;
    (S0 => O) = 390;
    (S1 => O) = 273;
  endspecify
endmodule