/* Copyright (C) 1997-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Richard Henderson (rth@tamu.edu).

   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 <asm/errno.h>

#include <asm/unistd.h>

#include <tcb-offsets.h>

#include <sysdep.h>

/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,

	     pid_t *ptid, void *tls, pid_t *ctid); */

	.register	%g2,#scratch

	.register	%g3,#scratch

	.text

ENTRY (__clone)

	save	%sp, -192, %sp

	cfi_def_cfa_register(%fp)

	cfi_window_save

	cfi_register(%o7, %i7)

	/* sanity check arguments */

	brz,pn	%i0, 99f		/* fn non-NULL? */

	 mov	%i0, %g2

	brz,pn	%i1, 99f		/* child_stack non-NULL? */

	 mov	%i2, %o0		/* clone flags */

	/* The child_stack is the top of the stack, allocate one

	   whole stack frame from that as this is what the kernel

	   expects.  Also, subtract STACK_BIAS.  */

	sub	%i1, 192 + 0x7ff, %o1

	mov	%i3, %g3

	mov	%i4,%o2			/* PTID */

	mov	%i5,%o3			/* TLS */

	ldx	[%fp+0x7ff+176],%o4	/* CTID */

	/* Do the system call */

	set	__NR_clone, %g1

	ta	0x6d

	bcs,pn	%xcc, 98f

	 nop

	brnz,pn	%o1, __thread_start

	 nop

	jmpl	%i7 + 8, %g0

	 restore %o0, %g0, %o0

99:	mov	EINVAL, %o0

98:	call	HIDDEN_JUMPTARGET(__errno_location)

	 mov	%o0, %i0

	st	%i0, [%o0]

	jmpl	%i7 + 8, %g0

	 restore %g0,-1,%o0

END(__clone)

	.type __thread_start,@function

__thread_start:

	mov	%g0, %fp	/* terminate backtrace */

	call	%g2

	 mov	%g3,%o0

	set	__NR_exit, %g1

	ta	0x6d

	 nop

	.size	__thread_start, .-__thread_start

libc_hidden_def (__clone)

weak_alias (__clone, clone)