_setjmp.S revision 1.5 1 /* $NetBSD: _setjmp.S,v 1.5 2020/05/04 06:42:11 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2002 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matthew Fredette.
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 <machine/asm.h>
33 #include <machine/frame.h>
34
35 #if defined(LIBC_SCCS) && !defined(lint)
36 RCSID("$NetBSD: _setjmp.S,v 1.5 2020/05/04 06:42:11 skrll Exp $")
37 #endif /* LIBC_SCCS and not lint */
38
39 /*
40 * C library -- setjmp, longjmp
41 *
42 * longjmp(a,v)
43 * will generate a "return(v)" from
44 * the last call to
45 * setjmp(a)
46 * by restoring registers from the stack,
47 * and a struct sigcontext, see <signal.h>
48 */
49
50 ENTRY(_setjmp,0)
51 /* A sigcontext is at the beginning of our jmp_buf. */
52 stw %r0, 0(%arg0) ; no onstack
53 stw %r0, 4(%arg0) ; unused word (old style signal mask)
54 stw %sp, 8(%arg0) ; sc.sc_sp = %sp
55 stw %r0, 16(%arg0) ; sc.sc_ap = NULL
56 mfsp %sr0, %r1
57 stw %r1, 20(%arg0) ; sc.sc_pcsqh = %sr0
58 stw %rp, 24(%arg0) ; sc.sc_pcoqh = %rp
59 stw %r1, 28(%arg0) ; sc.sc_pcsqh = %sr0
60 ldo 4(%rp), %r1
61 stw %r1, 32(%arg0) ; sc.sc_pcoqt = %rp + 4
62 stw %r0, 36(%arg0) ; set sc.sc_ps
63
64 /* We store all callee-saved registers after the sigcontext. */
65 ldo 56(%arg0), %r1
66 stwm %r3, 4(%r1)
67 stwm %r4, 4(%r1)
68 stwm %r5, 4(%r1)
69 stwm %r6, 4(%r1)
70 stwm %r7, 4(%r1)
71 stwm %r8, 4(%r1)
72 stwm %r9, 4(%r1)
73 stwm %r10, 4(%r1)
74 stwm %r11, 4(%r1)
75 stwm %r12, 4(%r1)
76 stwm %r13, 4(%r1)
77 stwm %r14, 4(%r1)
78 stwm %r15, 4(%r1)
79 stwm %r16, 4(%r1)
80 stwm %r17, 4(%r1)
81 stwm %r18, 4(%r1)
82
83 /* Return 0. */
84 bv %r0(%rp)
85 copy %r0, %ret0
86 EXIT(_setjmp)
87
88 ENTRY(_longjmp,0)
89 ldw 8(%arg0), %r1 ; ensure non-zero SP
90 combt,=,n %r0, %r1, botch ; oops!
91 add,<> %r0, %arg1, %ret0 ; ensure return value non-zero
92 ldi 1, %ret0
93
94 /* restore callee-saved registers */
95 ldo 56(%arg0), %r1
96 ldwm 4(%r1), %r3
97 ldwm 4(%r1), %r4
98 ldwm 4(%r1), %r5
99 ldwm 4(%r1), %r6
100 ldwm 4(%r1), %r7
101 ldwm 4(%r1), %r8
102 ldwm 4(%r1), %r9
103 ldwm 4(%r1), %r10
104 ldwm 4(%r1), %r11
105 ldwm 4(%r1), %r12
106 ldwm 4(%r1), %r13
107 ldwm 4(%r1), %r14
108 ldwm 4(%r1), %r15
109 ldwm 4(%r1), %r16
110 ldwm 4(%r1), %r17
111 ldwm 4(%r1), %r18
112
113 /* restore the rest */
114 ldw 8(%arg0), %sp
115 ldw 24(%arg0), %rp
116 bv %r0(%rp)
117 nop
118 botch:
119 bl longjmperror, %rp
120 nop
121 bl abort, %rp
122 nop
123 EXIT(_longjmp)
124
125 .end
126