| // DESCRIPTION: Verilator: Verilog Test module |
| // |
| // This file ONLY is placed into the Public Domain, for any use, |
| // without warranty, 2013. |
| |
| // bug648 |
| |
| 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 [7:0] datai = crc[7:0]; |
| wire enable = crc[8]; |
| |
| /*AUTOWIRE*/ |
| // Beginning of automatic wires (for undeclared instantiated-module outputs) |
| logic [7:0] datao; // From test of Test.v |
| // End of automatics |
| |
| Test test (/*AUTOINST*/ |
| // Outputs |
| .datao (datao[7:0]), |
| // Inputs |
| .clk (clk), |
| .datai (datai[7:0]), |
| .enable (enable)); |
| |
| // Aggregate outputs into a single result vector |
| wire [63:0] result = {56'h0, datao}; |
| |
| // 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; |
| sum <= 64'h0; |
| 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'h9d550d82d38926fa |
| if (sum !== `EXPECTED_SUM) $stop; |
| $write("*-* All Finished *-*\n"); |
| $finish; |
| end |
| end |
| |
| endmodule |
| |
| `define FAIL 1 |
| |
| module Nested |
| ( |
| input logic clk, |
| input logic x, |
| output logic y |
| ); |
| logic t; |
| always_comb t = x ^ 1'b1; |
| |
| always_ff @(posedge clk) begin |
| if (clk) |
| y <= t; |
| end |
| endmodule |
| |
| module Test |
| ( |
| input logic clk, |
| input logic [7:0] datai, |
| input logic enable, |
| output logic [7:0] datao |
| ); |
| |
| // verilator lint_off BLKANDNBLK |
| logic [7:0] datat; |
| // verilator lint_on BLKANDNBLK |
| |
| for (genvar i = 0; i < 8; i++) begin |
| if (i%4 != 3) begin |
| `ifndef FAIL |
| logic t; |
| always_comb begin |
| t = datai[i] ^ 1'b1; |
| end |
| always_ff @(posedge clk) begin |
| if (clk) |
| datat[i] <= t; |
| end |
| `else |
| Nested nested_i |
| ( |
| .clk(clk), |
| .x(datai[i]), |
| .y(datat[i]) //<== via Vcellout wire |
| ); |
| `endif |
| |
| always_comb begin |
| casez (enable) |
| 1'b1: datao[i] = datat[i]; |
| 1'b0: datao[i] = '0; |
| default: datao[i] = 'x; |
| endcase |
| end |
| end |
| else begin |
| always_ff @(posedge clk) begin |
| if (clk) |
| datat[i] <= 0; //<== assign delayed |
| end |
| always_comb begin |
| casez (enable) |
| 1'b1: datao[i] = datat[i] ^ 1'b1; |
| 1'b0: datao[i] = '1; |
| default: datao[i] = 'x; |
| endcase |
| end |
| end |
| end |
| endmodule |