1 /* Signal trampoline unwinder, for GDB the GNU Debugger.
3 Copyright 2004 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 #include "tramp-frame.h"
24 #include "frame-unwind.h"
29 #include "trad-frame.h"
30 #include "frame-base.h"
31 #include "gdb_assert.h"
35 const struct tramp_frame *tramp_frame;
38 struct tramp_frame_cache
41 const struct tramp_frame *tramp_frame;
42 struct trad_frame_cache *trad_cache;
45 static struct trad_frame_cache *
46 tramp_frame_cache (struct frame_info *next_frame,
49 CORE_ADDR pc = frame_pc_unwind (next_frame);
50 struct tramp_frame_cache *tramp_cache = (*this_cache);
51 if (tramp_cache->trad_cache == NULL)
53 tramp_cache->trad_cache = trad_frame_cache_zalloc (next_frame);
54 tramp_cache->tramp_frame->init (tramp_cache->tramp_frame,
56 tramp_cache->trad_cache,
59 return tramp_cache->trad_cache;
63 tramp_frame_this_id (struct frame_info *next_frame,
65 struct frame_id *this_id)
67 struct trad_frame_cache *trad_cache
68 = tramp_frame_cache (next_frame, this_cache);
69 trad_frame_get_id (trad_cache, this_id);
73 tramp_frame_prev_register (struct frame_info *next_frame,
77 enum lval_type * lvalp,
79 int *realnump, void *valuep)
81 struct trad_frame_cache *trad_cache
82 = tramp_frame_cache (next_frame, this_cache);
83 trad_frame_get_register (trad_cache, next_frame, prev_regnum, optimizedp,
84 lvalp, addrp, realnump, valuep);
88 tramp_frame_start (CORE_ADDR pc, const struct tramp_frame *tramp)
91 /* Search through the trampoline for one that matches the
92 instruction sequence around PC. */
93 for (ti = 0; tramp->insn[ti] != TRAMP_SENTINEL_INSN; ti++)
95 CORE_ADDR func = pc - tramp->insn_size * ti;
99 bfd_byte buf[sizeof (tramp->insn[0])];
101 if (tramp->insn[i] == TRAMP_SENTINEL_INSN)
103 if (target_read_memory (func + i * tramp->insn_size, buf,
104 tramp->insn_size) != 0)
106 insn = extract_unsigned_integer (buf, tramp->insn_size);
107 if (tramp->insn[i] != insn)
111 /* Trampoline doesn't match. */
116 tramp_frame_sniffer (const struct frame_unwind *self,
117 struct frame_info *next_frame,
120 const struct tramp_frame *tramp = self->unwind_data->tramp_frame;
121 CORE_ADDR pc = frame_pc_unwind (next_frame);
124 struct tramp_frame_cache *tramp_cache;
126 /* If the function has a valid symbol name, it isn't a
128 find_pc_partial_function (pc, &name, NULL, NULL);
131 /* If the function lives in a valid section (even without a starting
132 point) it isn't a trampoline. */
133 if (find_pc_section (pc) != NULL)
135 /* Finally, check that the trampoline matches at PC. */
136 func = tramp_frame_start (pc, tramp);
139 tramp_cache = FRAME_OBSTACK_ZALLOC (struct tramp_frame_cache);
140 tramp_cache->func = func;
141 tramp_cache->tramp_frame = tramp;
142 (*this_cache) = tramp_cache;
147 tramp_frame_append (struct gdbarch *gdbarch,
148 const struct tramp_frame *tramp_frame)
150 struct frame_data *data;
151 struct frame_unwind *unwinder;
154 /* Check that the instruction sequence contains a sentinel. */
155 for (i = 0; i < ARRAY_SIZE (tramp_frame->insn); i++)
157 if (tramp_frame->insn[i] == TRAMP_SENTINEL_INSN)
160 gdb_assert (i < ARRAY_SIZE (tramp_frame->insn));
161 gdb_assert (tramp_frame->insn_size <= sizeof (tramp_frame->insn[0]));
163 data = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_data);
164 unwinder = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind);
166 data->tramp_frame = tramp_frame;
167 unwinder->type = SIGTRAMP_FRAME;
168 unwinder->unwind_data = data;
169 unwinder->sniffer = tramp_frame_sniffer;
170 unwinder->this_id = tramp_frame_this_id;
171 unwinder->prev_register = tramp_frame_prev_register;
172 frame_unwind_register_unwinder (gdbarch, unwinder);