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/* Copyright (C) 1998, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <sysdep.h>
.text
ENTRY (__mmap)
/* Because we can only get five args through the syscall interface, and
mmap() takes six, we need to build a parameter block and pass its
address instead. The 386 port does a similar trick. */
/* This code previously moved sp into ip and stored the args using
stmdb ip!, {a1-a4}. It did not modify sp, so the stack never had
to be restored after the syscall completed. It saved an
instruction and meant no stack cleanup work was required.
This will not work in the case of a mmap call being interrupted
by a signal. If the signal handler uses any stack the arguments
to mmap will be trashed. The results of a restart of mmap are
then unpredictable. */
/* store args on the stack */
stmdb sp!, {a1-a4}
/* do the syscall */
mov a1, sp
swi SYS_ify (mmap)
/* pop args off the stack. */
add sp, sp, #16
cmn r0, $4096
RETINSTR(movcc, pc, lr)
b PLTJMP(syscall_error);
PSEUDO_END (__mmap)
weak_alias (__mmap, mmap)
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