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	Remove wide mux inference
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					 5 changed files with 3 additions and 195 deletions
				
			
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/*
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 *  yosys -- Yosys Open SYnthesis Suite
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 *
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 *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
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 *                2019  Eddie Hung    <eddie@fpgeh.com>
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 *
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 *  Permission to use, copy, modify, and/or distribute this software for any
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 *  purpose with or without fee is hereby granted, provided that the above
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 *  copyright notice and this permission notice appear in all copies.
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 *
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 *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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 *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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 *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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 *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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 *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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 *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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 *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 *
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 */
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module \$shiftx (A, B, Y);
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  parameter A_SIGNED = 0;
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  parameter B_SIGNED = 0;
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  parameter A_WIDTH = 1;
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  parameter B_WIDTH = 1;
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  parameter Y_WIDTH = 1;
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  input [A_WIDTH-1:0] A;
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  input [B_WIDTH-1:0] B;
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  output [Y_WIDTH-1:0] Y;
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  parameter [B_WIDTH-1:0] _TECHMAP_CONSTMSK_B_ = 0;
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  parameter [B_WIDTH-1:0] _TECHMAP_CONSTVAL_B_ = 0;
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  generate
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    genvar i, j;
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    // TODO: Check if this opt still necessary
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    if (B_SIGNED) begin
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      if (_TECHMAP_CONSTMSK_B_[B_WIDTH-1] && _TECHMAP_CONSTVAL_B_[B_WIDTH-1] == 1'b0)
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        // Optimisation to remove B_SIGNED if sign bit of B is constant-0
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        \$__XILINX_SHIFTX  #(.A_SIGNED(A_SIGNED), .B_SIGNED(0), .A_WIDTH(A_WIDTH), .B_WIDTH(B_WIDTH-1'd1), .Y_WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A), .B(B[B_WIDTH-2:0]), .Y(Y));
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      else
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        wire _TECHMAP_FAIL_ = 1;
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    end
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    else if (B_WIDTH < 3 || A_WIDTH <= 4) begin
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      wire _TECHMAP_FAIL_ = 1;
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    end
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    else begin
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        \$__XILINX_SHIFTX  #(.A_SIGNED(A_SIGNED), .B_SIGNED(B_SIGNED), .A_WIDTH(A_WIDTH), .B_WIDTH(B_WIDTH), .Y_WIDTH(Y_WIDTH)) _TECHMAP_REPLACE_ (.A(A), .B(B), .Y(Y));
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    end
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  endgenerate
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endmodule
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