1/*        $NetBSD: swapcontext.S,v 1.8 2013/09/12 15:36:16 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
34#if defined(LIBC_SCCS) && !defined(lint)
35          RCSID("$NetBSD: swapcontext.S,v 1.8 2013/09/12 15:36:16 joerg Exp $")
36#endif /* LIBC_SCCS && !lint */
37
38
39ENTRY(swapcontext)
40          mov       %o0, %o2                      /* must save pointer */
41          mov       %o1, %o3                      /* must save pointer */
42          mov       SYS_getcontext, %g1
43          t         ST_SYSCALL
44          bcc,a     1f
45           stx      %g0, [%o2 + 64 + 11 * 8]      /* gr[_REG_O0] = 0 */
46          ERROR()
471:
48          add       %o7, 12, %o1
49          stx       %o1, [%o2 + 64 + 2 * 8]                 /* gr[_REG_nPC] = retaddr + 4 */
50          add       %o7, 8, %o1
51          stx       %o1, [%o2 + 64 + 1 * 8]                 /* gr[_REG_PC] = retaddr */
52
53#if __PIC__ - 0 >= 2
54          PIC_PROLOGUE(%g5,%o4)                             /* %g5 = _GLOBAL_OFFSET_TABLE */
55          set       _C_LABEL(setcontext), %o5
56          ldx       [%g5+%o5], %o4
57          jmp       %o4
58           mov      %o3, %o0
59#elif __PIC__ - 0 >= 1
60          PIC_PROLOGUE(%g5,%o4)                             /* %g5 = _GLOBAL_OFFSET_TABLE */
61          ldx       [%g5+_C_LABEL(setcontext)], %o4
62          jmp       %o4
63           mov      %o3, %o0
64#else
65          ba,a      _C_LABEL(setcontext)
66           mov      %o3, %o0
67#endif
68