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/*  Special support for trampolines

 *

 *   Copyright (C) 1996, 1997, 2000 Free Software Foundation, Inc.

 *   Written By Michael Meissner

 *

 * This file is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License as published by the

 * Free Software Foundation; either version 2, or (at your option) any

 * later version.

 *

 * In addition to the permissions in the GNU General Public License, the

 * Free Software Foundation gives you unlimited permission to link the

 * compiled version of this file with other programs, and to distribute

 * those programs without any restriction coming from the use of this

 * file.  (The General Public License restrictions do apply in other

 * respects; for example, they cover modification of the file, and

 * distribution when not linked into another program.)

 *

 * This 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; see the file COPYING.  If not, write to

 * the Free Software Foundation, 51 Franklin Street, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 *

 *    As a special exception, if you link this library with files

 *    compiled with GCC to produce an executable, this does not cause

 *    the resulting executable to be covered by the GNU General Public License.

 *    This exception does not however invalidate any other reasons why

 *    the executable file might be covered by the GNU General Public License.

 */

/* Set up trampolines.  */

        .file   "tramp.asm"

        .section ".text"

        #include "ppc-asm.h"

#ifndef __powerpc64__

        .type   trampoline_initial,@object

        .align  2

trampoline_initial:

        mflr    r0

        bcl     20,31,1f

.Lfunc = .-trampoline_initial

        .long   0                        /* will be replaced with function address */

.Lchain = .-trampoline_initial

        .long   0                        /* will be replaced with static chain */

1:      mflr    r11

        mtlr    r0

        lwz     r0,0(r11)               /* function address */

        lwz     r11,4(r11)              /* static chain */

        mtctr   r0

        bctr

trampoline_size = .-trampoline_initial

        .size   trampoline_initial,trampoline_size

/* R3 = stack address to store trampoline */

/* R4 = length of trampoline area */

/* R5 = function address */

/* R6 = static chain */

FUNC_START(__trampoline_setup)

        mflr    r0              /* save return address */

        bcl     20,31,.LCF0     /* load up __trampoline_initial into r7 */

.LCF0:

        mflr    r11

        addi    r7,r11,trampoline_initial-4-.LCF0 /* trampoline address -4 */

        li      r8,trampoline_size      /* verify that the trampoline is big enough */

        cmpw    cr1,r8,r4

        srwi    r4,r4,2         /* # words to move */

        addi    r9,r3,-4        /* adjust pointer for lwzu */

        mtctr   r4

        blt     cr1,.Labort

        mtlr    r0

        /* Copy the instructions to the stack */

.Lmove:

        lwzu    r10,4(r7)

        stwu    r10,4(r9)

        bdnz    .Lmove

        /* Store correct function and static chain */

        stw     r5,.Lfunc(r3)

        stw     r6,.Lchain(r3)

        /* Now flush both caches */

        mtctr   r4

.Lcache:

        icbi    0,r3

        dcbf    0,r3

        addi    r3,r3,4

        bdnz    .Lcache

        /* Finally synchronize things & return */

        sync

        isync

        blr

.Labort:

#if defined SHARED && defined HAVE_AS_REL16

        bcl     20,31,1f

1:      mflr    r30

        addis   r30,r30,_GLOBAL_OFFSET_TABLE_-1b@ha

        addi    r30,r30,_GLOBAL_OFFSET_TABLE_-1b@l

#endif

        bl      JUMP_TARGET(abort)

FUNC_END(__trampoline_setup)

#endif