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/* Copyright (C) 1999, 2000 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
/* 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 <features.h>
#include <sys/syscall.h>
#define _ERRNO_H
#include <bits/errno.h>
#include <bits/sysnum.h>
#ifdef __PIC__
#define PLTJMP(_x) _x@PLT
#else
#define PLTJMP(_x) _x
#endif
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */
.text
.text
.align 4
.type clone,@function
.globl clone;
clone:
/* sanity check arguments. */
tst r4, r4
bt 0f
tst r5, r5
bf/s 1f
mov #+__NR_clone, r3
0:
bra __syscall_error
mov #-EINVAL, r4
1:
/* insert the args onto the new stack */
mov.l r7, @-r5
/* save the function pointer as the 0th element */
mov.l r4, @-r5
/* do the system call */
mov r6, r4
trapa #(__SH_SYSCALL_TRAP_BASE + 2)
mov r0, r1
#ifdef __sh2__
/* 12 arithmetic shifts for the crappy sh2, because shad doesn't exist! */
shar r1
shar r1
shar r1
shar r1
shar r1
shar r1
shar r1
shar r1
shar r1
shar r1
shar r1
shar r1
#else
mov #-12, r2
shad r2, r1
#endif
not r1, r1 /* r1=0 means r0 = -1 to -4095 */
tst r1, r1 /* i.e. error in linux */
bf/s 2f
tst r0, r0
bra __syscall_error
mov r0, r4
2:
bt 3f
rts
nop
3:
/* thread starts */
mov.l @r15, r1
jsr @r1
mov.l @(4,r15), r4
/* we are done, passing the return value through r0 */
mov.l .L1, r1
#ifdef __PIC__
mov.l r12, @-r15
sts.l pr, @-r15
mov r0, r4
mova .LG, r0 /* .LG from syscall_error.S */
mov.l .LG, r12
add r0, r12
mova .L1, r0
add r0, r1
jsr @r1
nop
lds.l @r15+, pr
rts
mov.l @r15+, r12
#else
jmp @r1
mov r0, r4
#endif
.align 2
.L1:
.long PLTJMP( HIDDEN_JUMPTARGET(_exit))
.size clone,.-clone;
#include "syscall_error.S"
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