module mux_128x1 (in,sel,out);
input [127:0] in;
input [6:0]sel;
output out;
wire out0_w, out1_w;

mux_64x1 m128_0(.in(in[63:0]),.sel(sel[5:0]),.out(out0_w));
mux_64x1 m128_1(.in(in[127:64]),.sel(sel[5:0]),.out(out1_w));
mux_2x1 m128_2(.a(out0_w),.b(out1_w),.sel(sel[6]),.out(out));

endmodule