Current File : //proc/self/root/glibc-2.29/sysdeps/unix/sysv/linux/csky/abiv2/clone.S
/* Wrapper around clone system call. C-SKY ABIV2 version.
Copyright (C) 2018-2019 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/>. */
/* 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>
/* int clone (int (*fn) (void *arg), void *child_stack, int flags, void *arg,
pid_t *ptid, struct user_desc *tls, pid_t *ctid) */
.text
ENTRY (__clone)
/* Sanity check arguments. */
cmpnei a0, 0 /* No NULL function pointers. */
bf __error_arg
cmpnei a1, 0 /* No NULL stack pointers. */
bf __error_arg
subi a1, 8
stw a0, (a1, 0) /* Insert the function into the new stack. */
stw a3, (a1, 4) /* Insert the args into the new stack. */
mov t1, r7 /* Save r7. */
mov t2, r4 /* Save r4. */
/* The syscall expects the args to be in different slots. */
mov a0, a2
ldw a2, (sp, 0)
ldw a3, (sp, 8)
ldw r4, (sp, 4)
lrw r7, __NR_clone
trap 0
mov r7, t1 /* Restore r7. */
mov r4, t2 /* Restore r4. */
btsti a0, 31 /* Check if return is less than zero. */
bt __do_syscall_error
cmpnei a0, 0
bf __child
rts
__error_arg:
lrw a0, -EINVAL
__do_syscall_error:
#ifdef __PIC__
subi sp, 8
stw gb, (sp, 0)
stw r15, (sp, 4)
grs gb, .Lgetpc
.Lgetpc:
lrw t0, .Lgetpc@GOTPC
addu gb, gb, t0
lrw t0, __syscall_error@PLT
ldr.w t0, (gb, t0 << 0)
jsr t0
ldw gb, (sp, 0)
ldw r15, (sp, 4)
addi sp, 8
#else
jmpi __syscall_error
#endif /* __PIC__ */
rts
PSEUDO_END (__clone)
__child:
ldw a0, (sp, 4) /* Restore args from new sp. */
ldw a1, (sp, 0) /* Restore function from new sp. */
addi sp, 8
jsr a1
/* exit */
lrw r7, __NR_exit
trap 0
libc_hidden_def (__clone)
weak_alias (__clone, clone)
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