glibc/sysdeps/unix/arm/fork.S
1997-05-21 01:39:40 +00:00

34 lines
1.2 KiB
ArmAsm

/* Copyright (C) 1991, 1992, 1994, 1995, 1997 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <sysdep.h>
/* ARM version. */
SYSCALL__ (fork, 0)
/* R1 is now 0 for the parent and 1 for the child. Decrement it to
make it -1 (all bits set) for the parent, and 0 (no bits set)
for the child. Then AND it with R0, so the parent gets
R0&-1==R0, and the child gets R0&0==0. */
sub r1, r1, $1
and r0, r0, r1
RETINSTR(mov, pc, r14)
PSEUDO_END(fork)
weak_alias (__fork, fork)