Subversion Repositories raptor64

`include "Raptor64_opcodes.v"

`timescale 1ns / 1ps

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

//        __

//   \\__/ o\    (C) 2012  Robert Finch

//    \  __ /    All rights reserved.

//     \/_//     robfinch<remove>@opencores.org

//       ||

//  

//      Raptor64_shift.v

//  - shift operations

//

//  

// 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/>.    

//                                                                          

//

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

//

module Raptor64_shift(xIR, a, b, mask, o, rolo);

input [31:0] xIR;

input [63:0] a;

input [63:0] b;

input [63:0] mask;

output [63:0] o;

reg [63:0] o;

output [63:0] rolo;

wire [6:0] xOpcode = xIR[31:25];

wire [5:0] xFunc = xIR[5:0];

wire [3:0] xFunc4 = xIR[3:0];

wire [127:0] shlxo = {64'd0,a} << b[5:0];

wire [127:0] shruxo = {a,64'd0} >> b[5:0];

wire [63:0] shlo = shlxo[63:0];

wire [63:0] shruo = shruxo[127:64];

assign rolo = {shlxo[127:64]|shlxo[63:0]};

wire [63:0] roro = {shruxo[127:64]|shruxo[63:0]};

wire [63:0] shro = ~(~a >> b[5:0]);

always @(xOpcode,xFunc,xFunc4,shlo,shruo,rolo,roro,shro,mask)

case(xOpcode)

`RR:

        case(xFunc)

        `SHL:   o = shlo;

        `SHLU:  o = shlo;

        `SHRU:  o = shruo;

        `ROL:   o = rolo;

        `ROR:   o = roro;

        `SHR:   o = shro;

        default:        o = 64'd0;

        endcase

`SHFTI:

        case(xFunc4)

        `SHLI:  o = shlo;

        `SHLUI: o = shlo;

        `SHRUI: o = shruo;

        `ROLI:  o = rolo;

        `RORI:  o = roro;

        `SHRI:  o = shro;

        default:        o = 64'd0;

        endcase

default:        o = 64'd0;

endcase

endmodule