| /* |
| * Copyright (c) 2002 Stephen Williams (steve@icarus.com) |
| * |
| * This source code is free software; you can redistribute it |
| * and/or modify it in source code form under the terms of the GNU |
| * General Public License as published by the Free Software |
| * Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA |
| */ |
| |
| /* |
| * This checks that ! of x works properly. |
| */ |
| |
| module main; |
| |
| reg x; |
| reg [1:0] xx; |
| |
| |
| initial begin |
| if (1'bx !== 1'bx) begin |
| $display("FAILED -- simple constant x does't compare."); |
| $finish; |
| end |
| |
| if (1'bx !== !1'bx) begin |
| $display("FAILED -- !1'bx comes out wrong."); |
| $finish; |
| end |
| |
| x = 1'bx; |
| if (x !== 1'bx) begin |
| $display("FAILED -- variable x comes out wrong."); |
| $finish; |
| end |
| |
| x = !x; |
| if (x !== 1'bx) begin |
| $display("FAILED -- ! of variable x comes out wrong."); |
| $finish; |
| end |
| |
| xx = 2'bx0; |
| if (xx !== 2'bx0) begin |
| $display("FAILED -- variable x comes out wrong."); |
| $finish; |
| end |
| |
| x = !xx; |
| if (x !== 1'bx) begin |
| $display("FAILED -- ! of variable xx comes out wrong."); |
| $finish; |
| end |
| |
| $display("PASSED"); |
| end |
| |
| endmodule // main |