1 /* Definitions for frame unwinder, for GDB, the GNU debugger.
3 Copyright (C) 2003, 2004, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "frame-unwind.h"
24 #include "dummy-frame.h"
25 #include "inline-frame.h"
29 #include "gdb_assert.h"
30 #include "gdb_obstack.h"
32 static struct gdbarch_data *frame_unwind_data;
34 struct frame_unwind_table_entry
36 const struct frame_unwind *unwinder;
37 struct frame_unwind_table_entry *next;
40 struct frame_unwind_table
42 struct frame_unwind_table_entry *list;
43 /* The head of the OSABI part of the search list. */
44 struct frame_unwind_table_entry **osabi_head;
48 frame_unwind_init (struct obstack *obstack)
50 struct frame_unwind_table *table
51 = OBSTACK_ZALLOC (obstack, struct frame_unwind_table);
52 /* Start the table out with a few default sniffers. OSABI code
53 can't override this. */
54 table->list = OBSTACK_ZALLOC (obstack, struct frame_unwind_table_entry);
55 table->list->unwinder = dummy_frame_unwind;
56 table->list->next = OBSTACK_ZALLOC (obstack, struct frame_unwind_table_entry);
57 table->list->next->unwinder = inline_frame_unwind;
58 /* The insertion point for OSABI sniffers. */
59 table->osabi_head = &table->list->next->next;
64 frame_unwind_prepend_unwinder (struct gdbarch *gdbarch,
65 const struct frame_unwind *unwinder)
67 struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
68 struct frame_unwind_table_entry *entry;
70 /* Insert the new entry at the start of the list. */
71 entry = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind_table_entry);
72 entry->unwinder = unwinder;
73 entry->next = (*table->osabi_head);
74 (*table->osabi_head) = entry;
78 frame_unwind_append_unwinder (struct gdbarch *gdbarch,
79 const struct frame_unwind *unwinder)
81 struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
82 struct frame_unwind_table_entry **ip;
84 /* Find the end of the list and insert the new entry there. */
85 for (ip = table->osabi_head; (*ip) != NULL; ip = &(*ip)->next);
86 (*ip) = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind_table_entry);
87 (*ip)->unwinder = unwinder;
90 const struct frame_unwind *
91 frame_unwind_find_by_frame (struct frame_info *this_frame, void **this_cache)
93 struct gdbarch *gdbarch = get_frame_arch (this_frame);
94 struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
95 struct frame_unwind_table_entry *entry;
97 for (entry = table->list; entry != NULL; entry = entry->next)
99 struct cleanup *old_cleanup;
101 old_cleanup = frame_prepare_for_sniffer (this_frame, entry->unwinder);
102 if (entry->unwinder->sniffer (entry->unwinder, this_frame,
105 discard_cleanups (old_cleanup);
106 return entry->unwinder;
108 do_cleanups (old_cleanup);
110 internal_error (__FILE__, __LINE__, _("frame_unwind_find_by_frame failed"));
113 /* A default frame sniffer which always accepts the frame. Used by
114 fallback prologue unwinders. */
117 default_frame_sniffer (const struct frame_unwind *self,
118 struct frame_info *this_frame,
119 void **this_prologue_cache)
124 /* Helper functions for value-based register unwinding. These return
125 a (possibly lazy) value of the appropriate type. */
127 /* Return a value which indicates that FRAME did not save REGNUM. */
130 frame_unwind_got_optimized (struct frame_info *frame, int regnum)
132 struct gdbarch *gdbarch = frame_unwind_arch (frame);
133 struct value *reg_val;
135 reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
136 set_value_optimized_out (reg_val, 1);
140 /* Return a value which indicates that FRAME copied REGNUM into
141 register NEW_REGNUM. */
144 frame_unwind_got_register (struct frame_info *frame, int regnum, int new_regnum)
146 return value_of_register_lazy (frame, new_regnum);
149 /* Return a value which indicates that FRAME saved REGNUM in memory at
153 frame_unwind_got_memory (struct frame_info *frame, int regnum, CORE_ADDR addr)
155 struct gdbarch *gdbarch = frame_unwind_arch (frame);
156 struct value *v = value_at_lazy (register_type (gdbarch, regnum), addr);
158 set_value_stack (v, 1);
162 /* Return a value which indicates that FRAME's saved version of
163 REGNUM has a known constant (computed) value of VAL. */
166 frame_unwind_got_constant (struct frame_info *frame, int regnum,
169 struct gdbarch *gdbarch = frame_unwind_arch (frame);
170 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
171 struct value *reg_val;
173 reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
174 store_unsigned_integer (value_contents_writeable (reg_val),
175 register_size (gdbarch, regnum), byte_order, val);
180 frame_unwind_got_bytes (struct frame_info *frame, int regnum, gdb_byte *buf)
182 struct gdbarch *gdbarch = frame_unwind_arch (frame);
183 struct value *reg_val;
185 reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
186 memcpy (value_contents_raw (reg_val), buf, register_size (gdbarch, regnum));
190 /* Return a value which indicates that FRAME's saved version of REGNUM
191 has a known constant (computed) value of ADDR. Convert the
192 CORE_ADDR to a target address if necessary. */
195 frame_unwind_got_address (struct frame_info *frame, int regnum,
198 struct gdbarch *gdbarch = frame_unwind_arch (frame);
199 struct value *reg_val;
201 reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
202 pack_long (value_contents_writeable (reg_val),
203 register_type (gdbarch, regnum), addr);
207 extern initialize_file_ftype _initialize_frame_unwind; /* -Wmissing-prototypes */
210 _initialize_frame_unwind (void)
212 frame_unwind_data = gdbarch_data_register_pre_init (frame_unwind_init);