verilator/test_regress/t/t_randcase.v

91 lines
2.4 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain.
// SPDX-FileCopyrightText: 2022 Wilson Snyder
// SPDX-License-Identifier: CC0-1.0
// verilog_format: off
`define stop $stop
`define check_range(gotv,minv,maxv) do if ((gotv) < (minv) || (gotv) > (maxv)) begin $write("%%Error: %s:%0d: got=%0d exp=%0d-%0d\n", `__FILE__,`__LINE__, (gotv), (minv), (maxv)); `stop; end while(0);
`define check_within_30_percent(gotv,val) `check_range((gotv), (val) * 70 / 100, (val) * 130 / 100)
// verilog_format: on
module t;
localparam int COUNT = 1000;
int v;
int counts[8];
function int randfunc();
int i;
randcase
0: i = 50; // Never
1: i = 100;
endcase
return i;
endfunction
initial begin
if (randfunc() != 100) $stop;
//
for (int i = 0; i < 8; ++i) counts[i] = 0;
for (int i = 0; i < COUNT; ++i) begin
randcase
0: ; // Never
0: counts[0]++; // Never
1: counts[1]++;
endcase
end
`check_range(counts[0], 0, 0);
`check_range(counts[1], COUNT, COUNT);
//
for (int i = 0; i < 8; ++i) counts[i] = 0;
for (int i = 0; i < COUNT; ++i) begin
randcase
i - i: counts[0]++; // Never
i + i + 1: counts[1]++;
endcase
end
`check_range(counts[0], 0, 0);
`check_range(counts[1], COUNT, COUNT);
//
for (int i = 0; i < 8; ++i) counts[i] = 0;
for (int i = 0; i < COUNT; ++i) begin
randcase
1: counts[0]++; // Never
4: counts[1]++;
endcase
end
`check_within_30_percent(counts[0], (COUNT * 1 / 5));
`check_within_30_percent(counts[1], (COUNT * 4 / 5));
//
for (int i = 0; i < 8; ++i) counts[i] = 0;
for (int i = 0; i < COUNT; ++i) begin
randcase
2: counts[0]++; // Never
2: counts[1]++; // Never
1: counts[2]++; // Never
1: counts[3]++; // Never
1: counts[4]++; // Never
1: counts[5]++; // Never
1: counts[6]++; // Never
1: counts[7]++; // Never
endcase
end
`check_within_30_percent(counts[0], (COUNT * 2 / 10));
`check_within_30_percent(counts[1], (COUNT * 2 / 10));
`check_within_30_percent(counts[2], (COUNT * 1 / 10));
`check_within_30_percent(counts[7], (COUNT * 1 / 10));
//
$write("*-* All Finished *-*\n");
$finish;
end
endmodule