Subversion Repositories raptor64

//=============================================================================

//      (C) 2006-2011  Robert Finch

//      All rights reserved.

//      robfinch@opencores.org

//

//      rol.v

//              Rotate or shift left by up to 64 bits.

//

//

// This source file is free software: you can redistribute it and/or modify 

// it under the terms of the GNU Lesser General Public License as published 

// by the Free Software Foundation, either version 3 of the License, or     

// (at your option) any later version.                                      

//                                                                          

// This source file 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 program.  If not, see <http://www.gnu.org/licenses/>.    

//                                                                          

//      Funnel rotater / shifter

//      Rotate, arithmetic shift left, or logical shift /

//      arithmetic shift right by 0 to 63 bits.

//      Parameterized with a default width of 32 bits.

//

//=============================================================================

//

// op

//      0        shift left

//      1       rotate left

module rol

#(parameter WID = 32)

(

input op,

input [WID:1] a,

input [5:0] b,

output [WID:1] o

);

wire [WID:1] t1, t2, t3;

assign o = t3;

rolx1  #(WID) u1 (op,  a, b[1:0], t1);

rolx4  #(WID) u2 (op, t1, b[3:2], t2);

rolx16 #(WID) u3 (op, t2, b[5:4], t3);

endmodule