verilator/test_regress/t/t_order_comboclkloop.v

73 lines
1.7 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain.
// SPDX-FileCopyrightText: 2003 Wilson Snyder
// SPDX-License-Identifier: CC0-1.0
module t (
input clk
);
// verilator lint_off COMBDLY
// verilator lint_off LATCH
// verilator lint_off UNOPT
// verilator lint_off UNOPTFLAT
// verilator lint_off MULTIDRIVEN
reg [31:0] runnerm1, runner;
initial runner = 0;
reg [31:0] runcount;
initial runcount = 0;
reg [31:0] clkrun;
initial clkrun = 0;
reg [31:0] clkcount;
initial clkcount = 0;
always @( /*AS*/ runner) begin
runnerm1 = runner - 32'd1;
end
reg run0;
always @( /*AS*/ runnerm1) begin
if ((runner & 32'hf) != 0) begin
runcount = runcount + 1;
runner = runnerm1;
$write(" seq runcount=%0d runner =%0x\n", runcount, runnerm1);
end
run0 = (runner[8:4] != 0 && runner[3:0] == 0);
end
always @(posedge run0) begin
// Do something that forces another combo run
clkcount <= clkcount + 1;
runner[8:4] <= runner[8:4] - 1;
runner[3:0] <= 3;
$write("[%0t] posedge runner=%0x\n", $time, runner);
end
reg [7:0] cyc;
initial cyc = 0;
always @(posedge clk) begin
$write("[%0t] %x counts %0x %0x\n", $time, cyc, runcount, clkcount);
cyc <= cyc + 8'd1;
case (cyc)
8'd00: begin
runner <= 0;
end
8'd01: begin
runner <= 32'h35;
end
default: ;
endcase
case (cyc)
8'd02: begin
if (runcount != 32'he) $stop;
if (clkcount != 32'h3) $stop;
end
8'd03: begin
$write("*-* All Finished *-*\n");
$finish;
end
default: ;
endcase
end
endmodule