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/* Copyright (C) 1993, 1994, 1995 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>
/* Since vfork shares the address space between the parent and child,
we must take care to avoid the child unwinding the stack frame and
clobbering it for the parent. */
.text
ENTRY (__vfork)
popl scratch /* Save the return PC in a register. */
DO_CALL (vfork, 0) /* Do the system call. */
pushl scratch /* Put the return PC back on the stack. */
jb syscall_error /* Branch if error. */
/* 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. */
decl r1
andl r1, r0
ret
weak_alias (__vfork, vfork)
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