glibc/sysdeps/unix/arm/fork.S

/* Copyright (C) 1991,92,94,95,97,2002 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 Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library.  If not, see
   <http://www.gnu.org/licenses/>.  */

#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
	DO_RET (r14)
PSEUDO_END (__fork)
libc_hidden_def (__fork)

weak_alias (__fork, fork)