yosys/tests/simple/task_func.v

36 lines
534 B
Verilog

module test01(clk, a, b, c, x, y, z, w);
input clk;
input [7:0] a, b, c;
output reg [7:0] x, y, z, w;
function [7:0] sum_shift;
input [3:0] s1, s2, s3;
sum_shift = s1 + (s2 << 2) + (s3 << 4);
endfunction
task reset_w;
w = 0;
endtask
task add_to;
output [7:0] out;
input [7:0] in;
out = out + in;
endtask
always @(posedge clk) begin
x = sum_shift(a, b, c);
y = sum_shift(a[7:4], b[5:2], c[3:0]);
z = sum_shift(a[0], b[5:4], c >> 5) ^ sum_shift(1, 2, 3);
reset_w;
add_to(w, x);
add_to(w, y);
add_to(w, z);
end
endmodule