1*35c34461Smatt/* $NetBSD: swapcontext.S,v 1.3 2015/03/27 23:23:14 matt Exp $ */ 26cf6fe02Smatt 36cf6fe02Smatt/*- 46cf6fe02Smatt * Copyright (c) 2001 The NetBSD Foundation, Inc. 56cf6fe02Smatt * All rights reserved. 66cf6fe02Smatt * 76cf6fe02Smatt * This code is derived from software contributed to The NetBSD Foundation 86cf6fe02Smatt * by Klaus Klein. 96cf6fe02Smatt * 106cf6fe02Smatt * Redistribution and use in source and binary forms, with or without 116cf6fe02Smatt * modification, are permitted provided that the following conditions 126cf6fe02Smatt * are met: 136cf6fe02Smatt * 1. Redistributions of source code must retain the above copyright 146cf6fe02Smatt * notice, this list of conditions and the following disclaimer. 156cf6fe02Smatt * 2. Redistributions in binary form must reproduce the above copyright 166cf6fe02Smatt * notice, this list of conditions and the following disclaimer in the 176cf6fe02Smatt * documentation and/or other materials provided with the distribution. 186cf6fe02Smatt * 196cf6fe02Smatt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 206cf6fe02Smatt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 216cf6fe02Smatt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 226cf6fe02Smatt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 236cf6fe02Smatt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 246cf6fe02Smatt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 256cf6fe02Smatt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 266cf6fe02Smatt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 276cf6fe02Smatt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 286cf6fe02Smatt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 296cf6fe02Smatt * POSSIBILITY OF SUCH DAMAGE. 306cf6fe02Smatt */ 316cf6fe02Smatt 326cf6fe02Smatt#include "SYS.h" 336cf6fe02Smatt#include "assym.h" 346cf6fe02Smatt 35*35c34461Smatt__RCSID("$NetBSD: swapcontext.S,v 1.3 2015/03/27 23:23:14 matt Exp $") 366cf6fe02Smatt 376cf6fe02Smatt#define CALLFRAME_UCP CALLFRAME_S1 386cf6fe02Smatt#define CALLFRAME_OUCP CALLFRAME_S0 396cf6fe02Smatt 406cf6fe02SmattENTRY(swapcontext) 416cf6fe02Smatt addi sp, sp, -CALLFRAME_SIZ # adjust stack 426cf6fe02Smatt REG_S ra, CALLFRAME_RA(sp) # save return address 436cf6fe02Smatt REG_S a0, CALLFRAME_OUCP(sp) # save oucp 446cf6fe02Smatt REG_S a1, CALLFRAME_UCP(sp) # save ucp 456cf6fe02Smatt 466cf6fe02Smatt call PLT(_C_LABEL(_getcontext)) # getcontext(oucp) 478a3081d2Smatt mv t0, a0 # save return value 486cf6fe02Smatt 496cf6fe02Smatt REG_L ra, CALLFRAME_RA(sp) # restore return address 506cf6fe02Smatt REG_L a0, CALLFRAME_UCP(sp) # load ucp 516cf6fe02Smatt REG_L a1, CALLFRAME_OUCP(sp) # load oucp for adjustment 526cf6fe02Smatt addi sp, sp, CALLFRAME_SIZ # restore stack 536cf6fe02Smatt 548a3081d2Smatt bnez t0, 1f # error? yes, cleanup 556cf6fe02Smatt 566cf6fe02Smatt REG_S ra, UC_GREGS_PC(a1) # pc <- ra 576cf6fe02Smatt REG_S sp, UC_GREGS_SP(a1) # adjust sp 586cf6fe02Smatt 59*35c34461Smatt tail PLT(_C_LABEL(setcontext)) # setcontext(ucp) 606cf6fe02Smatt 616cf6fe02Smatt1: ret # simply return 626cf6fe02SmattEND(swapcontext) 63