verilator/test_regress/t/t_select_plusloop.v

72 lines
1.9 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain.
// SPDX-FileCopyrightText: 2005 Wilson Snyder
// SPDX-License-Identifier: CC0-1.0
module t (
input clk
);
reg [31:0] narrow;
reg [63:0] quad;
reg [127:0] wide;
integer cyc;
initial cyc = 0;
reg [7:0] crc;
reg [6:0] index;
always @(posedge clk) begin
//$write("[%0t] cyc==%0d crc=%b n=%x\n", $time, cyc, crc, narrow);
cyc <= cyc + 1;
if (cyc == 0) begin
// Setup
narrow <= 32'h0;
quad <= 64'h0;
wide <= 128'h0;
crc <= 8'hed;
index <= 7'h0;
end
else if (cyc < 90) begin
index <= index + 7'h2;
crc <= {crc[6:0], ~^{crc[7], crc[5], crc[4], crc[3]}};
// verilator lint_off WIDTH
if (index < 9'd20) narrow[index+:3] <= crc[2:0];
if (index < 9'd60) quad[index+:3] <= crc[2:0];
if (index < 9'd120) wide[index+:3] <= crc[2:0];
//
narrow[index[3:0]] <= ~narrow[index[3:0]];
quad[~index[3:0]] <= ~quad[~index[3:0]];
wide[~index[3:0]] <= ~wide[~index[3:0]];
// verilator lint_on WIDTH
end
else if (cyc == 90) begin
wide[12+:4] <= 4'h6;
quad[12+:4] <= 4'h6;
narrow[12+:4] <= 4'h6;
wide[42+:4] <= 4'h6;
quad[42+:4] <= 4'h6;
wide[82+:4] <= 4'h6;
end
else if (cyc == 91) begin
wide[0] <= 1'b1;
quad[0] <= 1'b1;
narrow[0] <= 1'b1;
wide[41] <= 1'b1;
quad[41] <= 1'b1;
wide[81] <= 1'b1;
end
else if (cyc == 99) begin
$write("[%0t] cyc==%0d crc=%b n=%x q=%x w=%x\n", $time, cyc, crc, narrow, quad, wide);
if (crc != 8'b01111001) $stop;
if (narrow != 32'h001661c7) $stop;
if (quad != 64'h16d49b6f64266039) $stop;
if (wide != 128'h012fd26d265b266ff6d49b6f64266039) $stop;
$write("*-* All Finished *-*\n");
$finish;
end
end
endmodule