1 /* Definitions for frame unwinder, for GDB, the GNU debugger.
3 Copyright (C) 2003, 2004, 2007, 2008, 2009, 2010, 2011
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
);
53 /* Start the table out with a few default sniffers. OSABI code
54 can't override this. */
55 table
->list
= OBSTACK_ZALLOC (obstack
, struct frame_unwind_table_entry
);
56 table
->list
->unwinder
= &dummy_frame_unwind
;
57 table
->list
->next
= OBSTACK_ZALLOC (obstack
,
58 struct frame_unwind_table_entry
);
59 table
->list
->next
->unwinder
= &inline_frame_unwind
;
60 /* The insertion point for OSABI sniffers. */
61 table
->osabi_head
= &table
->list
->next
->next
;
66 frame_unwind_prepend_unwinder (struct gdbarch
*gdbarch
,
67 const struct frame_unwind
*unwinder
)
69 struct frame_unwind_table
*table
= gdbarch_data (gdbarch
, frame_unwind_data
);
70 struct frame_unwind_table_entry
*entry
;
72 /* Insert the new entry at the start of the list. */
73 entry
= GDBARCH_OBSTACK_ZALLOC (gdbarch
, struct frame_unwind_table_entry
);
74 entry
->unwinder
= unwinder
;
75 entry
->next
= (*table
->osabi_head
);
76 (*table
->osabi_head
) = entry
;
80 frame_unwind_append_unwinder (struct gdbarch
*gdbarch
,
81 const struct frame_unwind
*unwinder
)
83 struct frame_unwind_table
*table
= gdbarch_data (gdbarch
, frame_unwind_data
);
84 struct frame_unwind_table_entry
**ip
;
86 /* Find the end of the list and insert the new entry there. */
87 for (ip
= table
->osabi_head
; (*ip
) != NULL
; ip
= &(*ip
)->next
);
88 (*ip
) = GDBARCH_OBSTACK_ZALLOC (gdbarch
, struct frame_unwind_table_entry
);
89 (*ip
)->unwinder
= unwinder
;
92 /* Iterate through sniffers for THIS_FRAME frame until one returns with an
93 unwinder implementation. THIS_FRAME->UNWIND must be NULL, it will get set
94 by this function. Possibly initialize THIS_CACHE. */
97 frame_unwind_find_by_frame (struct frame_info
*this_frame
, void **this_cache
)
99 struct gdbarch
*gdbarch
= get_frame_arch (this_frame
);
100 struct frame_unwind_table
*table
= gdbarch_data (gdbarch
, frame_unwind_data
);
101 struct frame_unwind_table_entry
*entry
;
103 for (entry
= table
->list
; entry
!= NULL
; entry
= entry
->next
)
105 struct cleanup
*old_cleanup
;
107 old_cleanup
= frame_prepare_for_sniffer (this_frame
, entry
->unwinder
);
108 if (entry
->unwinder
->sniffer (entry
->unwinder
, this_frame
,
111 discard_cleanups (old_cleanup
);
114 do_cleanups (old_cleanup
);
116 internal_error (__FILE__
, __LINE__
, _("frame_unwind_find_by_frame failed"));
119 /* A default frame sniffer which always accepts the frame. Used by
120 fallback prologue unwinders. */
123 default_frame_sniffer (const struct frame_unwind
*self
,
124 struct frame_info
*this_frame
,
125 void **this_prologue_cache
)
130 /* Helper functions for value-based register unwinding. These return
131 a (possibly lazy) value of the appropriate type. */
133 /* Return a value which indicates that FRAME did not save REGNUM. */
136 frame_unwind_got_optimized (struct frame_info
*frame
, int regnum
)
138 struct gdbarch
*gdbarch
= frame_unwind_arch (frame
);
139 struct value
*reg_val
;
141 reg_val
= value_zero (register_type (gdbarch
, regnum
), not_lval
);
142 set_value_optimized_out (reg_val
, 1);
146 /* Return a value which indicates that FRAME copied REGNUM into
147 register NEW_REGNUM. */
150 frame_unwind_got_register (struct frame_info
*frame
,
151 int regnum
, int new_regnum
)
153 return value_of_register_lazy (frame
, new_regnum
);
156 /* Return a value which indicates that FRAME saved REGNUM in memory at
160 frame_unwind_got_memory (struct frame_info
*frame
, int regnum
, CORE_ADDR addr
)
162 struct gdbarch
*gdbarch
= frame_unwind_arch (frame
);
163 struct value
*v
= value_at_lazy (register_type (gdbarch
, regnum
), addr
);
165 set_value_stack (v
, 1);
169 /* Return a value which indicates that FRAME's saved version of
170 REGNUM has a known constant (computed) value of VAL. */
173 frame_unwind_got_constant (struct frame_info
*frame
, int regnum
,
176 struct gdbarch
*gdbarch
= frame_unwind_arch (frame
);
177 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
178 struct value
*reg_val
;
180 reg_val
= value_zero (register_type (gdbarch
, regnum
), not_lval
);
181 store_unsigned_integer (value_contents_writeable (reg_val
),
182 register_size (gdbarch
, regnum
), byte_order
, val
);
187 frame_unwind_got_bytes (struct frame_info
*frame
, int regnum
, gdb_byte
*buf
)
189 struct gdbarch
*gdbarch
= frame_unwind_arch (frame
);
190 struct value
*reg_val
;
192 reg_val
= value_zero (register_type (gdbarch
, regnum
), not_lval
);
193 memcpy (value_contents_raw (reg_val
), buf
, register_size (gdbarch
, regnum
));
197 /* Return a value which indicates that FRAME's saved version of REGNUM
198 has a known constant (computed) value of ADDR. Convert the
199 CORE_ADDR to a target address if necessary. */
202 frame_unwind_got_address (struct frame_info
*frame
, int regnum
,
205 struct gdbarch
*gdbarch
= frame_unwind_arch (frame
);
206 struct value
*reg_val
;
208 reg_val
= value_zero (register_type (gdbarch
, regnum
), not_lval
);
209 pack_long (value_contents_writeable (reg_val
),
210 register_type (gdbarch
, regnum
), addr
);
214 /* -Wmissing-prototypes */
215 extern initialize_file_ftype _initialize_frame_unwind
;
218 _initialize_frame_unwind (void)
220 frame_unwind_data
= gdbarch_data_register_pre_init (frame_unwind_init
);