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/******************************************************************************

*                                                                             *

* License Agreement                                                           *

*                                                                             *

* Copyright (c) 2003-2005 Altera Corporation, San Jose, California, USA.      *

* All rights reserved.                                                        *

*                                                                             *

* Permission is hereby granted, free of charge, to any person obtaining a     *

* copy of this software and associated documentation files (the "Software"),  *

* to deal in the Software without restriction, including without limitation   *

* the rights to use, copy, modify, merge, publish, distribute, sublicense,    *

* and/or sell copies of the Software, and to permit persons to whom the       *

* Software is furnished to do so, subject to the following conditions:        *

*                                                                             *

* The above copyright notice and this permission notice shall be included in  *

* all copies or substantial portions of the Software.                         *

*                                                                             *

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR  *

* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,    *

* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE *

* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER      *

* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING     *

* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER         *

* DEALINGS IN THE SOFTWARE.                                                   *

*                                                                             *

* This agreement shall be governed in all respects by the laws of the State   *

* of California and by the laws of the United States of America.              *

*                                                                             *

******************************************************************************/

        /*

         * This is the trap exception handler for Nios2.

         */

        /*

         * Provide a label which can be used to pull this file in.

         */

        .section .exceptions.start

        .globl alt_exception_trap

alt_exception_trap:

        /*

         * Pull in the entry/exit code.

         */

        .globl alt_exception

        .section .exceptions.soft, "xa"

.Ltrap_handler:

        /*

         * Did a trap instruction cause the exception?

         *

         * The instruction which the exception occurred on has been loaded

         * into r2 by code in alt_exception_entry.S

         *

         */

        movhi r3,0x003b              /* upper half of trap opcode */

        ori   r3,r3,0x683a           /* lower half of trap opcode */

        bne   r2,r3,.Lnot_trap

        /*

         *  There is no trap handler defined here, and so executing a trap

         *  instruction causes a software break.  If you provide a trap handler,

         *  then you must replace the break instruction below with your handler.

         *  Your handler must preserve ea and the usual callee saved registers.

         */

        break

        br   .Lexception_exit

.Lnot_trap:

        .section .exceptions.exit.label

.Lexception_exit: