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// ========== Copyright Header Begin ==========================================
//
// OpenSPARC T1 Processor File: tlu_prencoder16.v
// Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
// DO NOT ALTER OR REMOVE COPYRIGHT NOTICES.
//
// The above named program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public
// License version 2 as published by the Free Software Foundation.
//
// The above named program is distributed in the hope that it will be
// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public
// License along with this work; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
//
// ========== Copyright Header End ============================================
////////////////////////////////////////////////////////////////////////
/*
// Description: Datapath Priority Encoder 16b
// - 15b multihot vector as input
// - 15b 1-hit vector as output
// - Can use some std length such as 16b
// - msb is given highest priority
*/
////////////////////////////////////////////////////////////////////////
// Global header file includes
////////////////////////////////////////////////////////////////////////
`include "sys.h" // system level definition file which contains the
// time scale definition
////////////////////////////////////////////////////////////////////////
// Local header file includes / local defines
////////////////////////////////////////////////////////////////////////
module tlu_prencoder16 (din, dout);
input [14:0] din ;
output [3:0] dout ;
wire [14:0] onehot ;
assign onehot[14] = din[14] ;
assign onehot[13] = din[13] & ~din[14] ;
assign onehot[12] = din[12] & ~(|din[14:13]) ;
assign onehot[11] = din[11] & ~(|din[14:12]) ;
assign onehot[10] = din[10] & ~(|din[14:11]) ;
assign onehot[9] = din[9] & ~(|din[14:10]) ;
assign onehot[8] = din[8] & ~(|din[14:9]) ;
assign onehot[7] = din[7] & ~(|din[14:8]) ;
assign onehot[6] = din[6] & ~(|din[14:7]) ;
assign onehot[5] = din[5] & ~(|din[14:6]) ;
assign onehot[4] = din[4] & ~(|din[14:5]) ;
assign onehot[3] = din[3] & ~(|din[14:4]) ;
assign onehot[2] = din[2] & ~(|din[14:3]) ;
assign onehot[1] = din[1] & ~(|din[14:2]) ;
assign onehot[0] = din[0] & ~(|din[14:1]) ;
//assign onehot[0] = din[0] & ~(|din[15:1]) ;
assign dout[3] = |onehot[14:7] ;
assign dout[2] = (|onehot[6:3]) | (|onehot[14:11]) ;
assign dout[1] = (|onehot[2:1]) | (|onehot[6:5]) |
(|onehot[10:9]) | (|onehot[14:13]) ;
assign dout[0] = onehot[0] | onehot[2] | onehot[4] | onehot[6] |
onehot[8] | onehot[10] | onehot[12] | onehot[14] ;
endmodule