verilator/test_regress/t/t_cover_expr.v

186 lines
5.4 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain, for
// any use, without warranty, 2024 by Wilson Snyder.
// SPDX-License-Identifier: CC0-1.0
class cls;
rand int x;
endclass
module t (/*AUTOARG*/
// Inputs
clk
);
input clk;
integer cyc;
initial cyc=1;
logic [63:32] cyc2;
always_comb cyc2 = cyc;
integer some_int;
integer other_int;
logic some_bool;
wire t1 = cyc[0];
wire t2 = cyc[1];
wire t3 = cyc[2];
wire t4 = cyc[3];
localparam bit ONE = 1'b1;
localparam bit ZERO = 1'b0;
function automatic bit invert(bit x);
return ~x;
endfunction
function automatic bit and_oper(bit a, bit b);
return a & b;
endfunction
localparam int num_intfs = 4;
intf the_intfs [num_intfs-1:0] ();
genvar intf_i;
for (intf_i = 0; intf_i < num_intfs; intf_i++) begin
always_comb the_intfs[intf_i].t = cyc[intf_i];
end
always @ (posedge clk) begin
cyc <= cyc + 1;
if ((~cyc[0] && cyc[1]) || (~cyc[2] && cyc[3])) $write("");
if ((~cyc2[32] && cyc2[33]) || (~cyc2[34] && cyc2[35])) $write("");
if ((~the_intfs[0].t && the_intfs[1].t) || (~the_intfs[2].t && the_intfs[3].t)) $write("");
if ((~t1 && t2) || (~t3 && t4)) $write("");
if (t3 && (t1 == t2)) $write("");
if (123 == (124 - 32'(t1 || t2))) $write("");
some_int <= (t2 || t3) ? 345 : 567;
some_bool <= t1 && t2;
if (t1 & t2) $write("");
if ((!t1 && t2) | (~t3 && t4)) $write("");
if (t1 ^ t2) $write("");
if (~(t1 & t2)) $write("");
if (t1 -> t2) $write("");
if (t1 <-> t2) $write("");
if (&cyc[2:0]) $write("");
if (&cyc[3:2]) $write("");
if (|cyc[2:0]) $write("");
if (^cyc[2:0]) $write("");
if (|cyc[2:0] || cyc[3]) $write("");
if (t1 & t2 & 1'b1) $write("");
if (t1 & t2 & 1'b0) $write("");
if (t1 & t2 & ONE) $write("");
if (t1 & t2 & ZERO) $write("");
if (t1 && t2) begin
$write("");
end else if (t1 || t2) begin
$write("");
end
if (invert(t1) && t2) $write("");
if (and_oper(t1, t2)) $write("");
if (t2 && t3) begin
if (t1 && t2) $write("");
end
if (0 == 1) begin
for (int loop_var = 0; loop_var < 1; loop_var++) begin
if (cyc[loop_var] && t2) $write("");
end
end
// stop at the first layer even if there's more to find
if ((cyc[3+32'(t1 && t2)+:2] == cyc[5+32'(t3 || t4)+:2]) || cyc[31]) $write("");
// impossible branches and redundant terms
if ((t1 && t2) && ~(t1 && t3) && (t1 || t4)) $write("");
if ((cyc[0] && cyc[1]) && ~(cyc[0] && cyc[2]) && (cyc[0] || cyc[3])) $write("");
// demonstrate current limitations of term matching scheme
if ((cyc[0] && cyc[1]) && ~(cyc[1-1] && cyc[2]) && (cyc[2-2] || cyc[3])) $write("");
//verilator coverage_off
if (t1 && t2) $write("");
//verilator coverage_on
if ((~t1 && t2)
||
(~t3 && t4)) $write("");
// intentionally testing wonkified expression terms
if (
cyc[
0
] &
cyc
[1]) $write("");
// for now each ternary condition is considered in isolation
other_int <= t1 ? t2 ? 1 : 2 : 3;
// no expression coverage for multi-bit expressions
if ((cyc[1:0] & cyc[3:2]) == 2'b11) $write("");
// truth table is too large
if (^cyc[6:0]) $write("");
// this one is too big even for t_cover_expr_max
if (^cyc) $write("");
if (cyc==9) begin
$write("*-* All Finished *-*\n");
$finish;
end
end
always_comb begin
if (t1 && t2) $write("");
end
logic ta, tb, tc;
initial begin
cls obj = new;
cls null_obj = null;
int q[5];
int qv[$];
q = '{1, 2, 2, 4, 3};
// lambas not handled
// NB: there is a bug w/ tracing find_first (maybe lambdas in general?)
// tracing_off does not work around the bug
qv = q.find_first with (item[0] & item[1]);
ta = '1;
tb = '0;
tc = '0;
while (ta || tb || tc) begin
tc = tb;
tb = ta;
ta = '0;
end
if (!bit'(obj.randomize() with {x < 100;})) $write("");
if (null_obj != null && null_obj.x == 5) $write("");
end
sub the_sub_1 (.p(t1), .q(t2));
sub the_sub_2 (.p(t3), .q(t4));
// TODO -- non-process expressions
sub the_sub_3 (.p(t1 ? t2 : t3), .q(t4));
// TODO
// pragma for expr coverage off / on
// investigate cover point sorting in annotated source
// consider reporting don't care terms
//
// Branches which are statically impossible to reach are still reported.
// E.g.
// -000000 point: comment=(t1=1 && t2=1 && 1'h0=1) => 1 hier=top.t
// These could potentially be pruned, but they currently follow suit for
// what branch coverage does. Perhaps a switch should be added to not
// count statically impossible things.
endmodule
module sub (
input p,
input q
);
always_comb begin
if (p && q) $write("");
end
endmodule
interface intf();
logic t;
endinterface