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/* Copyright (C) 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <rth@tamu.edu>, 1996.
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>
#define _ERRNO_H 1
#include <bits/errno.h>
#include <sys/syscall.h>
#include <asm/regdef.h>
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg) */
.text
.globl __clone;
.align 3;
.ent __clone , 0;
__clone:
.frame $30 , 0, $26
.prologue 0
/* Sanity check arguments. */
ldiq v0,EINVAL
beq a0,$error /* no NULL function pointers */
beq a1,$error /* no NULL stack pointers */
/* Save the fn ptr and arg on the new stack. */
subq a1,16,a1
stq a0,0(a1)
stq a3,8(a1)
/* Do the system call */
mov a2,a0
ldiq v0,__NR_clone
call_pal 131
bne a3,$error
beq v0,thread_start
/* Successful return from the parent */
ret
/* Something bad happened -- no child created */
$error:
br gp,1f
1: ldgp gp,0(gp)
jmp zero,__syscall_error
.end __clone
/* Load up the arguments to the function. Put this block of code in
its own function so that we can terminate the stack trace with our
debug info. */
.ent thread_start
thread_start:
.frame fp,0,zero,0
mov zero,fp
.prologue 0
/* Load up the arguments. */
ldq pv,0($30)
ldq a0,8($30)
addq $30,16,$30
/* Call the user's function */
jsr ra,(pv)
ldgp gp,0(ra)
/* Call _exit rather than doing it inline for breakpoint purposes */
mov v0,a0
jsr ra,_exit
/* Die horribly. */
halt
.end thread_start
.weak clone;
clone = __clone
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