1/* $NetBSD: swapcontext.S,v 1.3 2008/04/28 20:22:57 martin 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 34#if defined(LIBC_SCCS) && !defined(lint) 35 .text 36 .asciz "$NetBSD: swapcontext.S,v 1.3 2008/04/28 20:22:57 martin Exp $" 37#endif /* LIBC_SCCS && !lint */ 38 39ENTRY(swapcontext) 40 mc_off = 56 # offset of uc_mcontext 41 stdu %r1,-SF_SZ(%r1) # set up new stack frame 42 mflr %r0 43 std %r0,[SF_SZ+SF_LR](%r1) # save link register 44 std %r3,SF_PARAM(%r1) # must save oucp (was 8) 45 std %r4,SF_PARAM+8(%r1) # must save ucp (was 12) 46 bl ._getcontext # getcontext(oucp) 47 nop 48 cmpdi %r3,0 49 bne 1f 50 ld %r11,SF_PARAM(%r1) # load oucp for adjustment 51 ld %r0,SF_SZ+SF_LR(%r1) # get LR back 52 std %r0,mc_off+34*8(%r11) # pc <- lr 53 la %r0,16(%r1) 54 std %r0,mc_off+1*8(%r11) # adjust sp 55 ld %r3,SF_PARAM+8(%r1) # load ucp 56 bl .setcontext # setcontext(ucp) 57 nop 581: 59 ld %r0,SF_SZ+SF_LR(%r1) 60 mtlr %r0 61 la %r1,SF_SZ(%r1) 62 blr 63