verilator/test_regress/t/t_gen_alw.v

// DESCRIPTION: Verilator: Verilog Test module
// This file ONLY is placed under the Creative Commons Public Domain, for
// any use, without warranty, 2020 by Wilson Snyder.
// SPDX-License-Identifier: CC0-1.0

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

   integer      cyc = 0;
   reg [63:0]   crc;
   reg [63:0]   sum;

   // Take CRC data and apply to testblock inputs
   wire [9:0]  in = crc[9:0];

   /*AUTOWIRE*/

   Test test (// Outputs
              .a(),
              .b(),
              /*AUTOINST*/
              // Inputs
              .clk                      (clk),
              .in                       (in[9:0]));

   // Aggregate outputs into a single result vector
   wire [63:0] result = {64'h0};

   // Test loop
   always @ (posedge clk) begin
`ifdef TEST_VERBOSE
      $write("[%0t] cyc==%0d crc=%x result=%x\n", $time, cyc, crc, result);
`endif
      cyc <= cyc + 1;
      crc <= {crc[62:0], crc[63] ^ crc[2] ^ crc[0]};
      sum <= result ^ {sum[62:0], sum[63] ^ sum[2] ^ sum[0]};
      if (cyc==0) begin
         // Setup
         crc <= 64'h5aef0c8d_d70a4497;
      end
      else if (cyc<10) begin
         sum <= 64'h0;
      end
      else if (cyc<90) begin
      end
      else if (cyc==99) begin
         $write("[%0t] cyc==%0d crc=%x sum=%x\n", $time, cyc, crc, sum);
         if (crc !== 64'hc77bb9b3784ea091) $stop;
         // What checksum will we end up with (above print should match)
`define EXPECTED_SUM 64'h0
         if (sum !== `EXPECTED_SUM) $stop;
         $write("*-* All Finished *-*\n");
         $finish;
      end
   end

endmodule

module Test (/*AUTOARG*/
   // Outputs
   a, b,
   // Inputs
   clk, in
   );
   /*verilator hier_block*/
   input clk;
   input [9:0] in;

   output reg a [9:0];
   integer ai;
   always @* begin
      for (ai=0;ai<10;ai=ai+1) begin
         a[ai]=in[ai];
      end
   end

   output reg [1:0] b [9:0];
   integer   j;

   generate
      genvar i;
      for (i=0; i<2; i=i+1) begin
         always @(posedge clk) begin
            for (j=0; j<10; j=j+1) begin
               if (a[j])
                 b[i][j] <= 1'b0;
               else
                 b[i][j] <= 1'b1;
            end
         end
      end
   endgenerate
endmodule