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/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Claire Xenia Wolf <claire@yosyshq.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
(* techmap_celltype = "$alu" *)
module _80_ice40_alu (A, B, CI, BI, X, Y, CO);
parameter A_SIGNED = 0;
parameter B_SIGNED = 0;
parameter A_WIDTH = 1;
parameter B_WIDTH = 1;
parameter Y_WIDTH = 1;
(* force_downto *)
input [A_WIDTH-1:0] A;
(* force_downto *)
input [B_WIDTH-1:0] B;
(* force_downto *)
output [Y_WIDTH-1:0] X, Y;
input CI, BI;
(* force_downto *)
output [Y_WIDTH-1:0] CO;
wire _TECHMAP_FAIL_ = Y_WIDTH <= 2;
(* force_downto *)
wire [Y_WIDTH-1:0] A_buf, B_buf;
\$pos #(.A_SIGNED(A_SIGNED), .A_WIDTH(A_WIDTH), .Y_WIDTH(Y_WIDTH)) A_conv (.A(A), .Y(A_buf));
\$pos #(.A_SIGNED(B_SIGNED), .A_WIDTH(B_WIDTH), .Y_WIDTH(Y_WIDTH)) B_conv (.A(B), .Y(B_buf));
(* force_downto *)
wire [Y_WIDTH-1:0] AA = A_buf;
(* force_downto *)
wire [Y_WIDTH-1:0] BB = BI ? ~B_buf : B_buf;
(* force_downto *)
wire [Y_WIDTH-1:0] C = {CO, CI};
genvar i;
generate for (i = 0; i < Y_WIDTH; i = i + 1) begin:slice
\$__ICE40_CARRY_WRAPPER #(
// A[0]: 1010 1010 1010 1010
// A[1]: 1100 1100 1100 1100
// A[2]: 1111 0000 1111 0000
// A[3]: 1111 1111 0000 0000
.LUT(16'b 0110_1001_1001_0110),
.I3_IS_CI(1'b1)
) carry (
.A(AA[i]),
.B(BB[i]),
.CI(C[i]),
.I0(1'b0),
.I3(1'bx),
.CO(CO[i]),
.O(Y[i])
);
end endgenerate
assign X = AA ^ BB;
endmodule
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