libucontext/arch/ppc64/startcontext.S

34 lines
1.0 KiB
ArmAsm

/*
* Copyright (c) 2018 Ariadne Conill <ariadne@dereferenced.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* This software is provided 'as is' and without any warranty, express or
* implied. In no event shall the authors be liable for any damages arising
* from the use of this software.
*/
#include "common-defs.h"
.hidden libucontext_trampoline
FUNC(libucontext_trampoline)
cmpdi 31,0 /* test if ucontext link pointer is null */
beq no_linked_context /* if it is, exit */
/* now, call SYS_swapcontext */
mr 4,31 /* ucp is in r31 */
li 3,0 /* don't care about restoring, set oucp to NULL */
li 5,1696 /* sizeof(ucontext_t) */
li 0,249 /* SYS_swapcontext */
sc
/* we should not wind back up here, if we do, exit with -1 */
li 3,-1
no_linked_context:
b exit@GOT
nop
END(libucontext_trampoline)