yosys4gal/techmaps/pla.v

`ifndef PLA_MAX_PRODUCTS
$fatal(1, "Macro PLA_MAX_PRODUCTS must be defined");
`endif

(* techmap_celltype = "$sop $__sop" *)
module _80_sop (A, Y);

parameter WIDTH = 0;
parameter DEPTH = 0;
parameter TABLE = 0;

input [WIDTH-1:0] A;
output reg Y;

// Add a blank variable to TABLE
function [2*(WIDTH+1)*DEPTH-1:0] add_var_table;
	integer i, j;
	for (i = 0; i < DEPTH; i=i+1) begin
		for (j = 0; j < WIDTH + 1; j=j+1) begin
			if (j < WIDTH) begin
				add_var_table[2*(WIDTH+1)*i + 2*j + 0] = TABLE[2*WIDTH*i + 2*j + 0];
				add_var_table[2*(WIDTH+1)*i + 2*j + 1] = TABLE[2*WIDTH*i + 2*j + 1];
			end else begin
				add_var_table[2*(WIDTH+1)*i + 2*j + 0] = 1'b0;
				add_var_table[2*(WIDTH+1)*i + 2*j + 1] = 1'b0;
			end
		end
	end
endfunction

generate
	genvar i, j;
	if (DEPTH <= `PLA_MAX_PRODUCTS) begin // Convert to GAL_SOP object if it fits
		GAL_SOP #(
			.WIDTH(WIDTH),
			.DEPTH(DEPTH),
			.TABLE(TABLE))
		_TECHMAP_REPLACE_ (
			.A(A),
			.Y(Y)
		);
	end else begin // Otherwise split into two new SOP objects
		wire partial;
		\$__sop #(
			.WIDTH(WIDTH),
			.DEPTH(`PLA_MAX_PRODUCTS),
			.TABLE(TABLE[2*WIDTH*`PLA_MAX_PRODUCTS-1:0])
		) sop_partial (
			.A(A),
			.Y(partial)
		);

		localparam EXTRA_VAR_TABLE = add_var_table();
		\$__sop #(
			.WIDTH(WIDTH+1),
			.DEPTH(DEPTH-`PLA_MAX_PRODUCTS+1),
			.TABLE({EXTRA_VAR_TABLE[2*(WIDTH+1)*DEPTH-1:2*(WIDTH+1)*`PLA_MAX_PRODUCTS], {2'b10, {{WIDTH}{2'b00}}}})
		) sop_rest (
			.A({partial, A}),
			.Y(Y)
		);
	end
endgenerate

endmodule