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module top();
wire [7:0] Z, CO;
reg [7:0] A, B, CI;
reg ok;
test test(Z, CO, A, B, CI);
task check;
input [7:0] want_z, want_co;
begin
$display("A = %d, B = %d, CI = %d", A, B, CI);
$display("==> Z = %d, CO = %d", Z, CO);
$display("??? Z = %d, CO = %d", want_z, want_co);
if (want_co !== CO || want_z !== Z) begin
$display("FAILED");
ok = 0;
end
$display;
end
endtask // check
initial begin
ok = 1;
A = 0;
B = 0;
CI = 0;
#1 check(0, 0);
A = 4;
#1 check(4, 0);
B = 251;
#1 check(255, 0);
if (ok)
$display("PASSED");
end
endmodule // top
module test (Z, CO, A, B, CI);
parameter width=8;
input [width-1:0] A, B, CI;
output [width-1:0] Z, CO;
reg [width-1:0] Z, CO;
integer i;
always @(A or B or CI) begin
for(i=0; i < width; i=i+1)
{CO[i],Z[i]} = A[i] + B[i] + CI[i];
end
endmodule
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