minix/lib/libc/arch/m68k/gen/swapcontext.S

52 lines
2.1 KiB
ArmAsm
Raw Normal View History

/* $NetBSD: swapcontext.S,v 1.6 2013/07/17 03:05:17 matt Exp $ */
/*-
* Copyright (c) 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Klaus Klein.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "SYS.h"
#include "assym.h"
#if defined(LIBC_SCCS) && !defined(lint)
RCSID("$NetBSD: swapcontext.S,v 1.6 2013/07/17 03:05:17 matt Exp $")
#endif /* LIBC_SCCS && !lint */
ENTRY(swapcontext)
movl 4(%sp),-(%sp) | push oucp on stack
jbsr PIC_PLT(_C_LABEL(_getcontext)) | getcontext(oucp)
tstl %d0 | OK?
jne L1
movl (%sp),%a0
addql #8,UC_MCONTEXT_SP(%a0) | adjust saved stack pointer (again)
movl %sp@(4),UC_MCONTEXT_PC(%a0) | adjust saved program counter (again)
movl 12(%sp),(%sp) | push ucp on stack
jbsr PIC_PLT(_C_LABEL(setcontext)) | setcontext(ucp)
L1: addql #4,%sp | pop ucp
rts
END(swapcontext)