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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 <asm/unistd.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#ifdef __HAVE_SHARED__
#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 #0x12
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 __HAVE_SHARED__
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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