swapcontext.S revision 1.1.4.2
1 1.1.4.2 tls /* $NetBSD: swapcontext.S,v 1.1.4.2 2014/08/20 00:02:08 tls Exp $ */ 2 1.1.4.2 tls 3 1.1.4.2 tls /*- 4 1.1.4.2 tls * Copyright (c) 2014 The NetBSD Foundation, Inc. 5 1.1.4.2 tls * All rights reserved. 6 1.1.4.2 tls * 7 1.1.4.2 tls * This code is derived from software contributed to The NetBSD Foundation 8 1.1.4.2 tls * by Matt Thomas of 3am Software Foundry. 9 1.1.4.2 tls * 10 1.1.4.2 tls * Redistribution and use in source and binary forms, with or without 11 1.1.4.2 tls * modification, are permitted provided that the following conditions 12 1.1.4.2 tls * are met: 13 1.1.4.2 tls * 1. Redistributions of source code must retain the above copyright 14 1.1.4.2 tls * notice, this list of conditions and the following disclaimer. 15 1.1.4.2 tls * 2. Redistributions in binary form must reproduce the above copyright 16 1.1.4.2 tls * notice, this list of conditions and the following disclaimer in the 17 1.1.4.2 tls * documentation and/or other materials provided with the distribution. 18 1.1.4.2 tls * 19 1.1.4.2 tls * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 1.1.4.2 tls * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 1.1.4.2 tls * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 1.1.4.2 tls * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 1.1.4.2 tls * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 1.1.4.2 tls * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 1.1.4.2 tls * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 1.1.4.2 tls * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 1.1.4.2 tls * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 1.1.4.2 tls * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 1.1.4.2 tls * POSSIBILITY OF SUCH DAMAGE. 30 1.1.4.2 tls */ 31 1.1.4.2 tls 32 1.1.4.2 tls #include <machine/asm.h> 33 1.1.4.2 tls #include "assym.h" 34 1.1.4.2 tls 35 1.1.4.2 tls #if defined(LIBC_SCCS) && !defined(lint) 36 1.1.4.2 tls RCSID("$NetBSD: swapcontext.S,v 1.1.4.2 2014/08/20 00:02:08 tls Exp $") 37 1.1.4.2 tls #endif /* LIBC_SCCS && !lint */ 38 1.1.4.2 tls 39 1.1.4.2 tls /* LINTSTUB: int swapcontext(ucontext_t * restrict, ucontext_t * restrict); */ 40 1.1.4.2 tls 41 1.1.4.2 tls ENTRY(swapcontext) 42 1.1.4.2 tls sub sp, sp, #32 /* allocate stack frame */ 43 1.1.4.2 tls stp x29, x30, [sp, #16] /* save FP & RA */ 44 1.1.4.2 tls add x29, sp, #16 /* new FP */ 45 1.1.4.2 tls stp x0, x1, [sp, #0] /* save oucp & ucp */ 46 1.1.4.2 tls 47 1.1.4.2 tls bl _C_LABEL(_getcontext) /* getcontext(oucp) */ 48 1.1.4.2 tls mov x3, x0 /* save return value */ 49 1.1.4.2 tls 50 1.1.4.2 tls ldp x2, x0, [sp, #0] /* restore oucp & ucp */ 51 1.1.4.2 tls ldp x29, x30, [sp, #16] /* restore FP & RA */ 52 1.1.4.2 tls add sp, sp, #32 /* free stack frame */ 53 1.1.4.2 tls 54 1.1.4.2 tls /* 55 1.1.4.2 tls * Assume _getcontext succeeded. 56 1.1.4.2 tls */ 57 1.1.4.2 tls mov x4, sp /* Get SP */ 58 1.1.4.2 tls str x4, [x2, #_UC_REGS_SP] /* Adjust saved SP. */ 59 1.1.4.2 tls str x30, [x2, #_UC_REGS_PC] /* Adjust saved LR. */ 60 1.1.4.2 tls 61 1.1.4.2 tls cbz x3, _C_LABEL(setcontext)/* setcontext if getcontext succeeded */ 62 1.1.4.2 tls mov x0, x3 /* restore getcontext return value */ 63 1.1.4.2 tls ret /* return on error from getcontext */ 64 1.1.4.2 tls END(swapcontext) 65
Indexes created Tue Oct 21 12:09:54 GMT 2025