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/* Copyright 2001 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Alexandre Oliva <aoliva@redhat.com>.
Based on ../i386/clone.S.
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. If not, see
<http://www.gnu.org/licenses/>. */
/* clone() is even more special than fork() as it mucks with stacks
and invokes a function in the right context after its all over. */
#include <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#include <asm-syntax.h>
#include <bp-sym.h>
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */
.text
ENTRY (BP_SYM (__clone))
/* Sanity check arguments. */
cmp 0,d0 /* no NULL function pointers */
beq L(error_inval)
cmp 0,d1 /* no NULL stack pointers */
beq L(error_inval)
/* Allocate room for a function call in the new stack, and
store fn and arg in it. They will be read back in
thread_start. */
mov d1,a0
sub 12,a0
mov d0,(a0)
mov (16,sp),d1
mov d1,(4,a0)
/* Do the system call */
mov a0,d1
mov (12,sp),a0
mov SYS_ify(clone),d0
syscall 0
cmp 0,d0
beq thread_start
blt L(to_SYSCALL_ERROR_LABEL)
L(pseudo_end):
ret
L(error_inval):
mov -EINVAL,d0
L(to_SYSCALL_ERROR_LABEL):
jmp SYSCALL_ERROR_LABEL
thread_start:
mov 0,a3 /* terminate the stack frame */
mov (4,sp),d0
mov (sp),a0
calls (a0)
#ifdef PIC
L(here):
mov pc,a2
add _GLOBAL_OFFSET_TABLE_-(L(here) - .),a2
#endif
call JUMPTARGET (_exit),[],0
PSEUDO_END (BP_SYM (__clone))
weak_alias (BP_SYM (__clone), BP_SYM (clone))
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