1/* $NetBSD: swapcontext.S,v 1.14 2013/11/30 20:20:42 joerg 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 1.14 2013/11/30 20:20:42 joerg Exp $") 37#endif /* LIBC_SCCS && !lint */ 38 39ENTRY(swapcontext) 40#if defined(__ARM_EABI__) && defined(__UNWIND_TABLES__) 41 .fnstart 42 .cfi_startproc 43#endif 44 push {r0-r2, lr} /* Must save oucp, ucp, lr. */ 45#if defined(__ARM_EABI__) && defined(__UNWIND_TABLES__) 46 .save {r0-r2, lr} 47 .cfi_def_cfa_offset 16 48 .cfi_offset 14, -4 49 .cfi_offset 2, -8 50 .cfi_offset 1, -12 51 .cfi_offset 0, -16 52#endif 53 bl PLT_SYM(_C_LABEL(_getcontext)) /* getcontext(oucp) */ 54 cmp r0, #0 55#if !defined(__thumb__) 56 pop {r0-r2, lr} 57#if defined(__ARM_EABI__) && defined(__UNWIND_TABLES__) 58 .cfi_def_cfa_offset 0 59#endif 60 RETc(ne) 61#else 62 pop {r0-r3} 63 beq 1f 64#if defined(__ARM_EABI__) && defined(__UNWIND_TABLES__) 65 .cfi_def_cfa_offset 0 66 .cfi_register 14, 3 67#endif 68 RETr(r3) 691: 70#endif 71#if !defined(__thumb__) 72 str sp, [r0, #_UC_REGS_SP] /* Adjust saved SP. */ 73 str lr, [r0, #_UC_REGS_PC] /* Adjust saved SP. */ 74#else 75 mov r2, sp 76 str r2, [r0, #_UC_REGS_SP] /* Adjust saved SP. */ 77 str r3, [r0, #_UC_REGS_PC] /* Adjust saved PC. */ 78 mov lr, r3 79#endif 80#ifdef SOFTFLOAT 81 /* Ahem. */ 82#endif 83 mov r0, r1 84#if !defined(__thumb__) || defined(_ARM_ARCH_T2) 85 b PLT_SYM(_C_LABEL(setcontext)) 86#else 87 push {lr} 88 bl PLT_SYM(_C_LABEL(setcontext)) 89 pop {pc} 90#endif 91#if defined(__ARM_EABI__) && defined(__UNWIND_TABLES__) 92 .cfi_endproc 93 .fnend 94#endif 95END(swapcontext) 96