题解 | #流水线乘法器#

`timescale 1ns/1ns

module multi_pipe#(
	parameter size = 4
)(
	input 						clk 		,   
	input 						rst_n		,
	input	[size-1:0]			mul_a		,
	input	[size-1:0]			mul_b		,
 
 	output	reg	[size*2-1:0]	mul_out		
);
reg[size*2-1:0]temp;
wire [size*2-1:0] temp0 ;
wire [size*2-1:0] temp1 ;
wire [size*2-1:0] temp2 ;
wire [size*2-1:0]temp3 ;
assign temp0 = mul_b[0]? mul_a : 'd0;
assign temp1 = mul_b[1]? (mul_a<<1) : 'd0;
assign temp2 = mul_b[2]? (mul_a<<2) : 'd0;
assign temp3 = mul_b[3]? (mul_a<<3) : 'd0;
always @(posedge clk or negedge rst_n) begin
       if(!rst_n) begin
              mul_out <= 'd0;
			  temp<=0;
       end
       else begin
              temp<=temp0+temp1+temp2+ temp3;
			  mul_out<=temp;
       end
end
endmodule