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#
# clone.S, part of the i960 support for the uClibc library.
#
# Copyright (C) 2002 by Okiok Data Ltd. http://www.okiok.com/
#
# This program 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.
#
# This program 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 this program; if not, write to the Free Software Foundation, Inc.,
# at 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Derived from an old port of uC-libc to the i960 by Keith Adams (kma@cse.ogi.edu).
#
#include <sys/syscall.h>
#include <bits/errno.h>
/* clone is even more special than fork as it mucks with stacks
and invokes a function in the right context after its all over. */
/* int _clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */
.globl clone
clone:
/* set up new stack image in regs r4-r7; argument will be in r3 in child. */
ldconst 0, r4 /* pfp == 0 */
addo 16, g1, r5 /* sp == newfp + 16 */
mov g0, r6 /* rip == fnc */
mov g2, r7
stq r4, (g1)
addo sp, 4, sp
st g10, -4(sp)
mov sp, g10
ldconst __NR_clone, g13
calls 0
/* Do the system call */
cmpibg 0, g0, __syscall_error /* if < 0, error */
be thread_start /* if == 0, we're the child */
ret /* we're the parent */
__syscall_error:
not g0, r3
callx ___errno_location
st r3, (g0)
ret
thread_start:
# our new pfp is in g1; here we go
flushreg
mov g1, pfp
flushreg
ret
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