8bitworkshop/test/cli/verilog/t_assign_inline.v

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed into the Public Domain, for any use,
// without warranty, 2015 by Mike Thyer.
// SPDX-License-Identifier: CC0-1.0

module t (/*AUTOARG*/
   // Inputs
   clk
   );
   input clk;

   int cycle=0;

   // verilator lint_off UNOPTFLAT
   reg  [7:0] a_r;
   wire [7:0] a_w;
   reg  [7:0] b_r;
   reg  [7:0] c_d_r, c_q_r;

   assign a_w = a_r;

   always @(*) begin
     a_r = 0;
     b_r = a_w;  // Substituting the a_w assignment to get b_r = 0 is wrong, as a_r is not "complete"
     a_r = c_q_r;
     c_d_r = c_q_r;
   end

   // stimulus + checks
   always @(posedge clk) begin
     cycle <= cycle+1;
     if (cycle==0) begin
       c_q_r <= 8'b0;
     end
     else begin
       c_q_r <= c_d_r+1;
`ifdef TEST_VERBOSE
       $display("[%0t] a_r=%0d, b_r=%0d", $time, a_r, b_r); // a_r and b_r should always be the same
`endif
     end
     if (cycle >= 10) begin
       if (b_r==9) begin
         $write("*-* All Finished *-*\n");
         $finish;
       end
       else begin
         $stop;
       end
     end
   end

endmodule