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/* $NetBSD: linux_sp_wrap_powerpc.S,v 1.2 2001/01/19 12:49:22 manu Exp $ */
/*-
* Copyright (c) 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Emmanuel Dreyfus.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <machine/asm.h>
/*
* See linux_exec_powerpc.c. Since the executable expects its arguments 16
* bytes lower than the place ld.so expects them, and since it was not
* possible to just duplicate the argument (ld.so erases the pace where
* the executable looks for the arguments), then we try to adjust the
* stack pointer after ld.so has done its job, and before the executable
* is actually run.
*
* This code is copied onto the stack before program startup, then
* ld.so is fooled in thinking this is the actual program. This code adjust
* the stack pointer so that the programm will find its arguments and then
* transfer control to the real program. The adjustment is of 16 bytes
*
* XXX This is really a ugly hack, and it should die.
*/
#define LINUX_SP_WRAP_OFFSET 0x10
.globl _C_LABEL(linux_sp_wrap_start)
.globl _C_LABEL(linux_sp_wrap_end)
.globl _C_LABEL(linux_sp_wrap_entry)
_C_LABEL(linux_sp_wrap_start):
addi 1,1,LINUX_SP_WRAP_OFFSET
mflr 12
bl 1f
1:
mflr 11
mtlr 12
lwz 12, _C_LABEL(linux_sp_wrap_entry)-1b(11)
mtctr 12
bctr
_C_LABEL(linux_sp_wrap_entry):
.long 0 /* orginal prog entry point. setup by kernel */
_C_LABEL(linux_sp_wrap_end):
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