Files
vortex/hw/rtl/libs/VX_pending_size.v
2021-01-09 16:32:55 -08:00

35 lines
798 B
Verilog

`include "VX_platform.vh"
module VX_pending_size #(
parameter SIZE = 1
) (
input wire clk,
input wire reset,
input wire push,
input wire pop,
output wire full
);
localparam ADDRW = $clog2(SIZE);
reg [ADDRW-1:0] size_r;
reg full_r;
always @(posedge clk) begin
if (reset) begin
size_r <= 0;
full_r <= 0;
end else begin
assert(!push || !full);
if (push) begin
if (!pop && (used_r == ADDRW'(SIZE-1)))
full_r <= 1;
end else if (pop) begin
full_r <= 0;
end
size_r <= size_r + ADDRW'($signed(2'(push && !pop) - 2'(pop && !push)));
end
end
assign full = full_r;
endmodule