verilator/test_regress/t/t_init_concat.v

84 lines
1.7 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain.
// SPDX-FileCopyrightText: 2004 Wilson Snyder
// SPDX-License-Identifier: CC0-1.0
module t (
input clk
);
integer cyc;
initial cyc = 1;
reg [31:0] wr_data;
reg wr_en;
wire [31:0] rd_data;
wire [1:0] rd_guards;
wire [1:0] rd_guardsok;
regfile regfile ( /*AUTOINST*/
// Outputs
.rd_data(rd_data[31:0]),
.rd_guards(rd_guards[1:0]),
.rd_guardsok(rd_guardsok[1:0]),
// Inputs
.wr_data(wr_data[31:0]),
.wr_en(wr_en),
.clk(clk)
);
initial wr_en = 0;
always @(posedge clk) begin
if (cyc != 0) begin
cyc <= cyc + 1;
if (cyc == 1) begin
if (!rd_guards[0]) $stop;
if (!rd_guardsok[0]) $stop;
wr_en <= 1'b1;
wr_data <= 32'hfeedf;
end
if (cyc == 2) begin
wr_en <= 0;
end
if (cyc == 3) begin
wr_en <= 0;
if (rd_data != 32'hfeedf) $stop;
if (rd_guards != 2'b11) $stop;
if (rd_guardsok != 2'b11) $stop;
end
if (cyc == 4) begin
$write("*-* All Finished *-*\n");
$finish;
end
end
end
endmodule
module regfile (
input [31:0] wr_data,
input wr_en,
output reg [31:0] rd_data,
output [1:0] rd_guards /*verilator public*/,
output [1:0] rd_guardsok /*verilator public*/,
input clk
);
always @(posedge clk) begin
if (wr_en) begin
rd_data <= wr_data;
end
end
// this initial statement will induce correct initialize behavior
// initial rd_guards= { 2'b11 };
assign rd_guards = {rd_data[0], 1'b1};
assign rd_guardsok[0] = 1'b1;
assign rd_guardsok[1] = rd_data[0];
endmodule // regfile