// DESCRIPTION: Verilator: Verilog Test module
//
// Test case #4: $root absolute hierarchical reference to tristate signal.
// A submodule reads a tristate signal from the top module via $root.
//
// This program is free software; you can redistribute it and/or modify it
// under the terms of either the GNU Lesser General Public License Version 3
// or the Perl Artistic License Version 2.0.
// SPDX-FileCopyrightText: 2026 Wilson Snyder
// SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0

// verilog_format: off
`define stop $stop
`define checkh(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d:  got='h%x exp='h%x\n", `__FILE__,`__LINE__, (gotv), (expv)); `stop; end while(0);
// verilog_format: on

module sub_root_reader (
    output logic [7:0] val
);
  assign val = $root.t.root_bus;
endmodule

module t;
  tri [7:0] root_bus;
  logic root_we;
  assign root_bus = root_we ? 8'hCC : 8'hzz;

  logic [7:0] root_readback;
  sub_root_reader u_reader (.val(root_readback));

  initial begin
    #1;
    root_we = 1'b0;
    #1;
    `checkh(root_readback, 8'hzz);

    #1;
    root_we = 1'b1;
    #1;
    `checkh(root_readback, 8'hCC);

    #1;
    root_we = 1'b0;
    #1;
    `checkh(root_readback, 8'hzz);

    #1;
    $write("*-* All Finished *-*\n");
    $finish;
  end
endmodule