1 /* libunwind - a platform-independent unwind library
2 Copyright (C) 2001-2004 Hewlett-Packard Co
3 Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
4
5 Permission is hereby granted, free of charge, to any person obtaining
6 a copy of this software and associated documentation files (the
7 "Software"), to deal in the Software without restriction, including
8 without limitation the rights to use, copy, modify, merge, publish,
9 distribute, sublicense, and/or sell copies of the Software, and to
10 permit persons to whom the Software is furnished to do so, subject to
11 the following conditions:
12
13 The above copyright notice and this permission notice shall be
14 included in all copies or substantial portions of the Software.
15
16 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
23
24 /* This illustrates the basics of using the unwind interface for
25 exception handling. */
26
27 #include "compiler.h"
28
29 #ifdef HAVE_CONFIG_H
30 # include "config.h"
31 #endif
32
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <unistd.h>
36
37 #include <libunwind.h>
38
39 #ifdef HAVE_IA64INTRIN_H
40 # include <ia64intrin.h>
41 #endif
42
43 #define panic(args...) \
44 { ++nerrors; fprintf (stderr, args); }
45
46 int nerrors = 0;
47 int verbose = 0;
48 int depth = 13;
49 volatile int got_here = 0;
50
51 extern void b (int);
52
53 void
raise_exception(void)54 raise_exception (void)
55 {
56 unw_cursor_t cursor;
57 unw_context_t uc;
58 int i;
59 unw_word_t ip;
60 unw_word_t sp;
61
62 unw_getcontext (&uc);
63 if (unw_init_local (&cursor, &uc) < 0)
64 {
65 panic ("unw_init_local() failed!\n");
66 return;
67 }
68
69 if (verbose)
70 {
71 printf ("raise_exception(): sp=%p\n", (void*) &sp);
72 unw_get_reg (&cursor, UNW_REG_IP, &ip);
73 unw_get_reg (&cursor, UNW_REG_SP, &sp);
74 printf ("\t #%-3d ip=%p sp=%p\n", 0, (void*) ip, (void*) sp);
75 }
76
77 /* unwind to top-most frame a(), skipping over b() and raise_exception(): */
78 for (i = 0; i < depth + 2; ++i)
79 if (unw_step (&cursor) < 0)
80 {
81 panic ("unw_step() failed!\n");
82 return;
83 }
84 else if (verbose)
85 {
86 unw_get_reg (&cursor, UNW_REG_IP, &ip);
87 unw_get_reg (&cursor, UNW_REG_SP, &sp);
88 printf ("\t #%-3d ip=%p sp=%p\n", i + 1, (void*) ip, (void*) sp);
89 }
90 unw_resume (&cursor); /* transfer control to exception handler */
91 }
92
93 uintptr_t
get_bsp(void)94 get_bsp (void)
95 {
96 #if UNW_TARGET_IA64
97 # ifdef __INTEL_COMPILER
98 return __getReg (_IA64_REG_AR_BSP);
99 # else
100 return (uintptr_t) __builtin_ia64_bsp ();
101 # endif
102 #else
103 return 0;
104 #endif
105 }
106
107 int NOINLINE
a(int n)108 a (int n)
109 {
110 long stack;
111 int result = 99;
112
113 if (verbose)
114 printf ("a(n=%d): sp=%p bsp=0x%lx\n",
115 n, &stack, (unsigned long) get_bsp ());
116
117 if (n > 0)
118 a (n - 1);
119 else
120 b (16);
121
122 if (verbose)
123 {
124 printf ("exception handler: here we go (sp=%p, bsp=0x%lx)...\n",
125 &stack, (unsigned long) get_bsp ());
126 /* This call works around a bug in gcc (up-to pre3.4) which
127 causes invalid assembly code to be generated when
128 __builtin_ia64_bsp() gets predicated. */
129 getpid ();
130 }
131 if (n == depth)
132 {
133 result = 0;
134 got_here = 1;
135 }
136 return result;
137 }
138
139 void NOINLINE
b(int n)140 b (int n)
141 {
142 if ((n & 1) == 0)
143 {
144 if (verbose)
145 printf ("b(n=%d) calling raise_exception()\n", n);
146 raise_exception ();
147 }
148 panic ("FAILURE: b() returned from raise_exception()!!\n");
149 }
150
151 int
main(int argc,char ** argv)152 main (int argc, char **argv)
153 {
154 int result;
155
156 if (argc > 1)
157 {
158 ++verbose;
159 depth = atol (argv[1]);
160 if (depth < 1)
161 {
162 fprintf (stderr, "Usage: %s depth\n"
163 " depth must be >= 1\n", argv[0]);
164 exit (-1);
165 }
166 }
167
168 result = a (depth);
169 if (result != 0 || !got_here || nerrors > 0)
170 {
171 fprintf (stderr,
172 "FAILURE: test failed: result=%d got_here=%d nerrors=%d\n",
173 result, got_here, nerrors);
174 exit (-1);
175 }
176
177 if (verbose)
178 printf ("SUCCESS!\n");
179 return 0;
180 }
181