1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
5 * T R A C E B A C K - G C C t a b l e s *
7 * C Implementation File *
9 * Copyright (C) 2004-2007, AdaCore *
10 * Copyright (C) 2008, Free Software Foundation, Inc. *
12 * GNAT is free software; you can redistribute it and/or modify it under *
13 * terms of the GNU General Public License as published by the Free Soft- *
14 * ware Foundation; either version 2, or (at your option) any later ver- *
15 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
16 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
17 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
18 * for more details. You should have received a copy of the GNU General *
19 * Public License distributed with GNAT; see file COPYING. If not, write *
20 * to the Free Software Foundation, 51 Franklin Street, Fifth Floor, *
21 * Boston, MA 02110-1301, USA. *
23 * As a special exception, if you link this file with other files to *
24 * produce an executable, this file does not by itself cause the resulting *
25 * executable to be covered by the GNU General Public License. This except- *
26 * ion does not however invalidate any other reasons why the executable *
27 * file might be covered by the GNU Public License. *
29 * GNAT was originally developed by the GNAT team at New York University. *
30 * Extensive contributions were provided by Ada Core Technologies Inc. *
32 ****************************************************************************/
34 /* This is an implementation of the __gnat_backtrace routine using the
35 underlying GCC unwinding support associated with the exception handling
36 infrastructure. This will only work for ZCX based applications. */
40 /* The implementation boils down to a call to _Unwind_Backtrace with a
41 tailored callback and carried-on data structure to keep track of the
42 input parameters we got as well as of the basic processing state. */
48 #if !defined (__USING_SJLJ_EXCEPTIONS__)
60 #if defined (__ia64__) && defined (__hpux__)
64 static _Unwind_Reason_Code
65 trace_callback (struct _Unwind_Context * uw_context, uw_data_t * uw_data)
69 #if defined (__ia64__) && defined (__hpux__)
70 /* Work around problem with _Unwind_GetIP on ia64 HP-UX. */
71 uwx_get_reg ((struct uwx_env *) uw_context, UWX_REG_IP, (uint64_t *) &pc);
73 pc = (void *) _Unwind_GetIP (uw_context);
76 if (uw_data->n_frames_skipped < uw_data->n_frames_to_skip)
78 uw_data->n_frames_skipped ++;
79 return _URC_NO_REASON;
82 if (uw_data->n_entries_filled >= uw_data->max_len)
83 return _URC_NORMAL_STOP;
85 if (pc < uw_data->exclude_min || pc > uw_data->exclude_max)
86 uw_data->traceback [uw_data->n_entries_filled ++] = pc + PC_ADJUST;
88 return _URC_NO_REASON;
98 __gnat_backtrace (void ** traceback, int max_len,
99 void * exclude_min, void * exclude_max,
102 #if defined (__USING_SJLJ_EXCEPTIONS__)
103 /* We have no unwind material (tables) at hand with sjlj eh, and no
104 way to retrieve complete and accurate call chain information from
105 the context stack we maintain. */
109 /* State carried over during the whole unwinding process. */
111 uw_data.traceback = traceback;
112 uw_data.max_len = max_len;
113 uw_data.exclude_min = exclude_min;
114 uw_data.exclude_max = exclude_max;
116 uw_data.n_frames_to_skip = skip_frames;
118 uw_data.n_frames_skipped = 0;
119 uw_data.n_entries_filled = 0;
121 _Unwind_Backtrace ((_Unwind_Trace_Fn)trace_callback, &uw_data);
123 return uw_data.n_entries_filled;