karatsuba_mult_163.v

module karatsuba_mult_163(
    A, B, C
);

parameter m=163;
parameter n=325;
input [m-1:0]A;
input [m-1:0]B;
output [n-1:0]C;


parameter p=(m+1)/2;

wire [p-1:0]A_l, B_l;
wire [p-2:0] A_h, B_h;
wire [2*p-4:0]C1;
wire [2*p-2:0]C4, C5, C6; //C1=A_h*B_h, C4=A_l*B_l, C_2=A_h+A_l, C_3=B_h+B_l, C_6=(A_h+A_l)*(B_h+B_l)+A_h*B_h+A_l*B_l
wire [p-1:0]C2, C3;

// wire [p-1:0]A_h, B_h, A_l, B_l;
// wire [2*p-2:0]C1, C4, C5, C6; //C1=A_h*B_h, C4=A_l*B_l, C_2=A_h+A_l, C_3=B_h+B_l, C_6=(A_h+A_l)*(B_h+B_l)+A_h*B_h+A_l*B_l
// wire [p-1:0]C2, C3;

assign A_l=A[p-1:0];
assign A_h=A[m-1:p];
assign B_l=B[p-1:0];
assign B_h=B[m-1:p];

assign C2=A_h^A_l;
assign C3=B_h^B_l;

// initial begin
// $display("at163=%b\n", A);
// end

karatsuba_mult_81 M1(A_h, B_h, C1);
karatsuba_mult_82 M2(A_l, B_l, C4);
karatsuba_mult_82 M3(C2, C3, C5);
assign C6=C5^C1^C4;


assign C=(C1<<(m+1))^(C6<<p)^C4;

endmodule