xref: /netbsd-src/sys/arch/hppa/hppa/sigcode.S (revision 9eed11091fdd35825be6fcc76f8279773c2b4135)
1/*	$NetBSD: sigcode.S,v 1.10 2021/10/28 11:11:11 christos Exp $	*/
2
3/*	$OpenBSD: locore.S,v 1.46 2001/09/20 18:33:03 mickey Exp $	*/
4
5/*
6 * Copyright (c) 1998-2004 Michael Shalayeff
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
22 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
28 * THE POSSIBILITY OF SUCH DAMAGE.
29 *
30 * Portitions of this file are derived from other sources, see
31 * the copyrights and acknowledgements below.
32 */
33/*
34 * Copyright (c) 1990,1991,1992,1994 The University of Utah and
35 * the Computer Systems Laboratory (CSL).  All rights reserved.
36 *
37 * THE UNIVERSITY OF UTAH AND CSL PROVIDE THIS SOFTWARE IN ITS "AS IS"
38 * CONDITION, AND DISCLAIM ANY LIABILITY OF ANY KIND FOR ANY DAMAGES
39 * WHATSOEVER RESULTING FROM ITS USE.
40 *
41 * CSL requests users of this software to return to csl-dist@cs.utah.edu any
42 * improvements that they make and grant CSL redistribution rights.
43 *
44 *	Utah $Hdr: locore.s 1.62 94/12/15$
45 */
46/*
47 *  (c) Copyright 1988 HEWLETT-PACKARD COMPANY
48 *
49 *  To anyone who acknowledges that this file is provided "AS IS"
50 *  without any express or implied warranty:
51 *      permission to use, copy, modify, and distribute this file
52 *  for any purpose is hereby granted without fee, provided that
53 *  the above copyright notice and this notice appears in all
54 *  copies, and that the name of Hewlett-Packard Company not be
55 *  used in advertising or publicity pertaining to distribution
56 *  of the software without specific, written prior permission.
57 *  Hewlett-Packard Company makes no representations about the
58 *  suitability of this software for any purpose.
59 */
60
61/*
62 * NOTICE: This is not a standalone file.  To use it, #include it in
63 * your port's locore.S, like so:
64 *
65 *	#include <hppa/hppa/sigcode.S>
66 */
67
68/*
69 * Signal "trampoline" code. Invoked from RTE setup by sendsig().
70 */
71ENTRY_NOPROFILE(sigcode,0)
72	.call
73	/*
74	 * Our sendsig() places the address of the signal handler
75	 * in %arg3.  It may actually be a PLABEL.
76	 */
77	bb,>=,n	%arg3, 30, L$sigcode_bounce	; branch if not a PLABEL
78	depi	0, 31, 2, %arg3			; zero L bit in PLABEL pointer
79	ldw	4(%arg3), %r19			; load shared library linkage
80	ldw	0(%arg3), %arg3			; load real catcher address
81L$sigcode_bounce:
82	/*
83	 * This blr puts the address of the following nop in rp.
84	 * It also schedules the nop for execution, which is why
85	 * that instruction has to be a nop, or, rather, not any
86	 * instruction only meant to execute once the signal handler
87	 * returns.
88	 */
89	blr	%r0, %rp
90	/*
91	 * This bv schedules the instruction pointed to by arg3
92	 * for execution.  So, arg3 is the address of the signal
93	 * handler.
94	 */
95	bv,n	%r0(%arg3)
96	nop
97	/*
98	 * The signal handler has returned.  Since %r3 is on the list
99	 * of callee-saved registers, it's whatever the sendsig
100	 * code wanted it set to.  Since we copy it into arg0,
101	 * it looks like sendsig leaves %r3 holding the desired
102	 * single argument to sys___sigreturn14, i.e., the
103	 * struct sigcontext *.
104	 */
105	/* Make a SYS___sigreturn14 system call. */
106	copy	%r3, %arg0
107	ldil	L%SYSCALLGATE, %r1
108	.call
109	ble	4(%sr7, %r1)
110	ldi	SYS_compat_16___sigreturn14, %t1
111	/* Make a SYS_exit system call. */
112	copy	%ret0, %arg0
113	ldil	L%SYSCALLGATE, %r1
114	.call
115	ble	4(%sr7, %r1)
116	ldi	SYS_exit, %t1
117ALTENTRY(esigcode)
118EXIT(sigcode)
119