1/* $NetBSD: swapcontext.S,v 1.6 2013/07/17 03:05:17 matt Exp $ */ 2 3/*- 4 * Copyright (c) 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Klaus Klein. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include "SYS.h" 33#include "assym.h" 34 35#if defined(LIBC_SCCS) && !defined(lint) 36 RCSID("$NetBSD: swapcontext.S,v 1.6 2013/07/17 03:05:17 matt Exp $") 37#endif /* LIBC_SCCS && !lint */ 38 39ENTRY(swapcontext) 40 movl 4(%sp),-(%sp) | push oucp on stack 41 jbsr PIC_PLT(_C_LABEL(_getcontext)) | getcontext(oucp) 42 tstl %d0 | OK? 43 jne L1 44 movl (%sp),%a0 45 addql #8,UC_MCONTEXT_SP(%a0) | adjust saved stack pointer (again) 46 movl %sp@(4),UC_MCONTEXT_PC(%a0) | adjust saved program counter (again) 47 movl 12(%sp),(%sp) | push ucp on stack 48 jbsr PIC_PLT(_C_LABEL(setcontext)) | setcontext(ucp) 49L1: addql #4,%sp | pop ucp 50 rts 51END(swapcontext) 52