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////                                                              ////

////  OR1200's reg2mem aligner                                    ////

////                                                              ////

////  This file is part of the OpenRISC 1200 project              ////

////  http://www.opencores.org/cores/or1k/                        ////

////                                                              ////

////  Description                                                 ////

////  Aligns register data to memory alignment.                   ////

////                                                              ////

////  To Do:                                                      ////

////   - make it smaller and faster                               ////

////                                                              ////

////  Author(s):                                                  ////

////      - Damjan Lampret, lampret@opencores.org                 ////

////                                                              ////

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////                                                              ////

//// Copyright (C) 2000 Authors and OPENCORES.ORG                 ////

////                                                              ////

//// This source file may be used and distributed without         ////

//// restriction provided that this copyright statement is not    ////

//// removed from the file and that any derivative work contains  ////

//// the original copyright notice and the associated disclaimer. ////

////                                                              ////

//// 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 2.1 of the License, or (at your option) any   ////

//// later version.                                               ////

////                                                              ////

//// This source 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 Lesser General Public License for more ////

//// details.                                                     ////

////                                                              ////

//// You should have received a copy of the GNU Lesser General    ////

//// Public License along with this source; if not, download it   ////

//// from http://www.opencores.org/lgpl.shtml                     ////

////                                                              ////

//////////////////////////////////////////////////////////////////////

//

// CVS Revision History

//

// $Log: not supported by cvs2svn $

// Revision 1.1.1.1  2001/10/06 10:18:36  igorm

// no message

//

// Revision 1.2  2001/08/09 13:39:33  lampret

// Major clean-up.

//

// Revision 1.1  2001/07/20 00:46:21  lampret

// Development version of RTL. Libraries are missing.

//

//

// synopsys translate_off

`include "timescale.v"

// synopsys translate_on

`include "defines.v"

module reg2mem(addr, lsu_op, regdata, memdata);

parameter width = `OPERAND_WIDTH;

//

// I/O

//

input   [1:0]                    addr;

input   [`LSUOP_WIDTH-1:0]       lsu_op;

input   [width-1:0]              regdata;

output  [width-1:0]              memdata;

//

// Internal regs and wires

//

reg     [width-1:0]              memdata;

//

// Mux to memdata[31:24]

//

always @(lsu_op or addr or regdata) begin

        casex({lsu_op, addr[1:0]})       // synopsys full_case parallel_case

                {`LSUOP_SB, 2'b00} : memdata[31:24] = regdata[7:0];

                {`LSUOP_SH, 2'b00} : memdata[31:24] = regdata[15:8];

                default : memdata[31:24] = regdata[31:24];

        endcase

end

//

// Mux to memdata[23:16]

//

always @(lsu_op or addr or regdata) begin

        casex({lsu_op, addr[1:0]})       // synopsys full_case parallel_case

                {`LSUOP_SW, 2'b00} : memdata[23:16] = regdata[23:16];

                default : memdata[23:16] = regdata[7:0];

        endcase

end

//

// Mux to memdata[15:8]

//

always @(lsu_op or addr or regdata) begin

        casex({lsu_op, addr[1:0]})       // synopsys full_case parallel_case

                {`LSUOP_SB, 2'b10} : memdata[15:8] = regdata[7:0];

                default : memdata[15:8] = regdata[15:8];

        endcase

end

//

// Mux to memdata[7:0]

//

always @(regdata)

        memdata[7:0] = regdata[7:0];

endmodule