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// baeckler - 2-13-2006
// compute sum of 36 bit lines
//
// uses nine 6:3 compressors = 27 six-luts
// plus a 5 bit carry propagate output adder (one bit falls through)

module thirtysix_six_comp (data,sum);

input [31:0] data;
output [31:0] sum;
wire [31:0] sum;

wire [5:0] word_l;
wire [5:0] word_m;
wire [5:0] word_h;

wire [2:0] sa,sb,sc,sd,se,sf;
wire [2:0] slo,sme,shi;

six_three_comp a (.data(data[5:0]),.sum(sa));
six_three_comp b (.data(data[11:6]),.sum(sb));
six_three_comp c (.data(data[17:12]),.sum(sc));
six_three_comp d (.data(data[23:18]),.sum(sd));
six_three_comp e (.data(data[29:24]),.sum(se));
six_three_comp f (.data({4'b0,data[31:30]}),.sum(sf));

six_three_comp lo (.data({sa[0],sb[0],sc[0],sd[0],se[0],sf[0]}),.sum(slo));
six_three_comp me (.data({sa[1],sb[1],sc[1],sd[1],se[1],sf[1]}),.sum(sme));
six_three_comp hi (.data({sa[2],sb[2],sc[2],sd[2],se[2],sf[2]}),.sum(shi));

wire [7:0] tmp_sum;
ternary_add t (.a({3'b0,slo}),
			.b({2'b0,sme,1'b0}),
			.c({1'b0,shi,2'b0}),
			.o(tmp_sum));
	defparam t .WIDTH = 6;
assign sum = {26'b0,tmp_sum[5:0]};

endmodule
