glibc/sysdeps/unix/sysv/linux/arm/clone.S
Ulrich Drepper e361ccd999 Update.
2002-12-20  Art Haas  <ahaas@airmail.net>

	* sysdeps/gnu/siglist.c: Convert GCC extension initializer
	syntax to C99.

2002-12-21  Philip Blundell  <philb@gnu.org>

	* sysdeps/arm/elf/start.S (_start): Optimise a little.  Push stack
	top as seventh arg to __libc_start_main.
	Reported by paulnash@wildseed.com.

	* sysdeps/unix/sysv/linux/arm/clone.S: Small optimisation.

	* sysdeps/unix/sysv/linux/arm/sigcontextinfo.h: Elide
	compatibility cruft when new enough kernel is assumed.
2002-12-21 18:53:25 +00:00

61 lines
1.8 KiB
ArmAsm

/* Copyright (C) 1996, 1997, 1998, 1999, 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Pat Beirne <patb@corelcomputer.com>
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 <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg); */
.text
ENTRY(__clone)
@ sanity check args
cmp r0, #0
cmpne r1, #0
moveq r0, #-EINVAL
beq PLTJMP(syscall_error)
@ insert the args onto the new stack
str r3, [r1, #-4]!
str r0, [r1, #-4]!
@ do the system call
@ get flags
mov r0, r2
@ new sp is already in r1
swi SYS_ify(clone)
movs a1, a1
blt PLTJMP(C_SYMBOL_NAME(__syscall_error))
RETINSTR(movne, pc, lr)
@ pick the function arg and call address off the stack and execute
ldr r0, [sp, #4]
mov lr, pc
ldr pc, [sp]
@ and we are done, passing the return value through r0
b PLTJMP(_exit)
PSEUDO_END (__clone)
weak_alias (__clone, clone)