module mask_decode(enc_mask_s1, data_in_s1, true_bits_s1, false_bits_s1);   input [3:0] enc_mask_s1;   input [14:0] data_in_s1;   output [14:0] true_bits_s1;   output [14:0] false_bits_s1;         reg [14:0] 	 true_bits_s1;   reg [14:0] 	 false_bits_s1;   reg [14:0]    mask_bits_s1;   always @ (enc_mask_s1 or mask_bits_s1 or data_in_s1)     begin	case (enc_mask_s1)	  4'b0000: mask_bits_s1 = 15'h0000;	  4'b0001: mask_bits_s1 = 15'h0001;	  4'b0010: mask_bits_s1 = 15'h0003;	  4'b0011: mask_bits_s1 = 15'h0007;	  4'b0100: mask_bits_s1 = 15'h000f;	  4'b0101: mask_bits_s1 = 15'h001f;	  4'b0110: mask_bits_s1 = 15'h003f;	  4'b0111: mask_bits_s1 = 15'h007f;	  4'b1000: mask_bits_s1 = 15'h00ff;	  4'b1001: mask_bits_s1 = 15'h01ff;	  4'b1010: mask_bits_s1 = 15'h03ff;	  4'b1011: mask_bits_s1 = 15'h07ff;	  4'b1100: mask_bits_s1 = 15'h0fff;	  4'b1101: mask_bits_s1 = 15'h1fff;	  4'b1110: mask_bits_s1 = 15'h3fff;	  4'b1111: mask_bits_s1 = 15'h7fff;/*** _Will_ never happen because every combo is covered above ***//***	  // should never happen	  default: $display("ERROR: in mask decode at %d", $time); ***/	endcase		// now false_bits_s1 has decoded mask, where it has 1	// every place the bit should be masked	// Remember, to be masked both T and F bits must be 0		// true bits are 1 when they are *not* masked, and	// they also happen to be a 1	true_bits_s1 = (~mask_bits_s1) & data_in_s1;		// false bits are 1 when they are not masked and the	// data in is a 0	false_bits_s1 = (~mask_bits_s1) & (~data_in_s1);     end   endmodule // mask_decode