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// nandgame ALU
`timescale 1us/1us
`include "nandgame_types.v"
`include "arith_unit.sv"
`include "logic_unit.sv"
`ifndef NANDGAME_ALU
`define NANDGAME_ALU
module alu #(
parameter DATA_WIDTH = 16
) (
// "X" operand
input [(DATA_WIDTH-1):0] X_in,
// "Y" operand
input [(DATA_WIDTH-1):0] Y_in,
// "u" flag. 1=arithmetic, 0=logic operation
input logic u_arith_nlogic_in,
// opcode, see ArithCode / LogicCode
input logic [1:0] opcode_in,
// zero the "X" operand
input logic zx_in,
// swap "X" and "Y" operands
input logic sw_in,
// result of operation
output logic [(DATA_WIDTH-1):0] result_out
);
logic [(DATA_WIDTH-1):0] int_op_x /* verilator public */;
logic [(DATA_WIDTH-1):0] int_op_y /* verilator public */;
logic [(DATA_WIDTH-1):0] int_result_arith;
logic [(DATA_WIDTH-1):0] int_result_logic;
assign int_op_x = zx_in ? 0
: (sw_in ? Y_in : X_in);
assign int_op_y = sw_in ? X_in : Y_in;
arith_unit au (
.X_in(int_op_x),
.Y_in(int_op_y),
.result_out(int_result_arith),
.arith_operation_in(ArithCode'(opcode_in))
);
logic_unit lu (
.X_in(int_op_x),
.Y_in(int_op_y),
.result_out(int_result_logic),
.logic_operation_in(LogicCode'(opcode_in))
);
assign result_out = u_arith_nlogic_in ? int_result_arith : int_result_logic;
endmodule
`endif
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