Commit | Line | Data |
---|---|---|
4f460812 | 1 | /* Cache and manage frames for GDB, the GNU debugger. |
96cb11df | 2 | |
6aba47ca DJ |
3 | Copyright (C) 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, 2001, |
4 | 2002, 2003, 2004, 2007 Free Software Foundation, Inc. | |
d65fe839 AC |
5 | |
6 | This file is part of GDB. | |
7 | ||
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 2 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
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. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with this program; if not, write to the Free Software | |
197e01b6 EZ |
20 | Foundation, Inc., 51 Franklin Street, Fifth Floor, |
21 | Boston, MA 02110-1301, USA. */ | |
d65fe839 AC |
22 | |
23 | #include "defs.h" | |
24 | #include "frame.h" | |
25 | #include "target.h" | |
26 | #include "value.h" | |
39f77062 | 27 | #include "inferior.h" /* for inferior_ptid */ |
4e052eda | 28 | #include "regcache.h" |
4f460812 | 29 | #include "gdb_assert.h" |
e36180d7 | 30 | #include "gdb_string.h" |
eb8bc282 | 31 | #include "user-regs.h" |
4c1e7e9d AC |
32 | #include "gdb_obstack.h" |
33 | #include "dummy-frame.h" | |
a94dd1fd | 34 | #include "sentinel-frame.h" |
4c1e7e9d AC |
35 | #include "gdbcore.h" |
36 | #include "annotate.h" | |
6e7f8b9c | 37 | #include "language.h" |
494cca16 | 38 | #include "frame-unwind.h" |
da62e633 | 39 | #include "frame-base.h" |
eb4f72c5 AC |
40 | #include "command.h" |
41 | #include "gdbcmd.h" | |
f4c5303c | 42 | #include "observer.h" |
c8cd9f6c | 43 | #include "objfiles.h" |
60250e8b | 44 | #include "exceptions.h" |
eb4f72c5 | 45 | |
5613d8d3 AC |
46 | static struct frame_info *get_prev_frame_1 (struct frame_info *this_frame); |
47 | ||
bd013d54 AC |
48 | /* We keep a cache of stack frames, each of which is a "struct |
49 | frame_info". The innermost one gets allocated (in | |
50 | wait_for_inferior) each time the inferior stops; current_frame | |
51 | points to it. Additional frames get allocated (in get_prev_frame) | |
52 | as needed, and are chained through the next and prev fields. Any | |
53 | time that the frame cache becomes invalid (most notably when we | |
54 | execute something, but also if we change how we interpret the | |
55 | frames (e.g. "set heuristic-fence-post" in mips-tdep.c, or anything | |
56 | which reads new symbols)), we should call reinit_frame_cache. */ | |
57 | ||
58 | struct frame_info | |
59 | { | |
60 | /* Level of this frame. The inner-most (youngest) frame is at level | |
61 | 0. As you move towards the outer-most (oldest) frame, the level | |
62 | increases. This is a cached value. It could just as easily be | |
63 | computed by counting back from the selected frame to the inner | |
64 | most frame. */ | |
bbde78fa | 65 | /* NOTE: cagney/2002-04-05: Perhaps a level of ``-1'' should be |
bd013d54 AC |
66 | reserved to indicate a bogus frame - one that has been created |
67 | just to keep GDB happy (GDB always needs a frame). For the | |
68 | moment leave this as speculation. */ | |
69 | int level; | |
70 | ||
bd013d54 AC |
71 | /* The frame's low-level unwinder and corresponding cache. The |
72 | low-level unwinder is responsible for unwinding register values | |
73 | for the previous frame. The low-level unwind methods are | |
bbde78fa | 74 | selected based on the presence, or otherwise, of register unwind |
bd013d54 AC |
75 | information such as CFI. */ |
76 | void *prologue_cache; | |
77 | const struct frame_unwind *unwind; | |
78 | ||
79 | /* Cached copy of the previous frame's resume address. */ | |
80 | struct { | |
81 | int p; | |
82 | CORE_ADDR value; | |
83 | } prev_pc; | |
84 | ||
85 | /* Cached copy of the previous frame's function address. */ | |
86 | struct | |
87 | { | |
88 | CORE_ADDR addr; | |
89 | int p; | |
90 | } prev_func; | |
91 | ||
92 | /* This frame's ID. */ | |
93 | struct | |
94 | { | |
95 | int p; | |
96 | struct frame_id value; | |
97 | } this_id; | |
98 | ||
99 | /* The frame's high-level base methods, and corresponding cache. | |
100 | The high level base methods are selected based on the frame's | |
101 | debug info. */ | |
102 | const struct frame_base *base; | |
103 | void *base_cache; | |
104 | ||
105 | /* Pointers to the next (down, inner, younger) and previous (up, | |
106 | outer, older) frame_info's in the frame cache. */ | |
107 | struct frame_info *next; /* down, inner, younger */ | |
108 | int prev_p; | |
109 | struct frame_info *prev; /* up, outer, older */ | |
55feb689 DJ |
110 | |
111 | /* The reason why we could not set PREV, or UNWIND_NO_REASON if we | |
112 | could. Only valid when PREV_P is set. */ | |
113 | enum unwind_stop_reason stop_reason; | |
bd013d54 AC |
114 | }; |
115 | ||
ac2bd0a9 AC |
116 | /* Flag to control debugging. */ |
117 | ||
118 | static int frame_debug; | |
920d2a44 AC |
119 | static void |
120 | show_frame_debug (struct ui_file *file, int from_tty, | |
121 | struct cmd_list_element *c, const char *value) | |
122 | { | |
123 | fprintf_filtered (file, _("Frame debugging is %s.\n"), value); | |
124 | } | |
ac2bd0a9 | 125 | |
25d29d70 AC |
126 | /* Flag to indicate whether backtraces should stop at main et.al. */ |
127 | ||
128 | static int backtrace_past_main; | |
920d2a44 AC |
129 | static void |
130 | show_backtrace_past_main (struct ui_file *file, int from_tty, | |
131 | struct cmd_list_element *c, const char *value) | |
132 | { | |
133 | fprintf_filtered (file, _("\ | |
134 | Whether backtraces should continue past \"main\" is %s.\n"), | |
135 | value); | |
136 | } | |
137 | ||
2315ffec | 138 | static int backtrace_past_entry; |
920d2a44 AC |
139 | static void |
140 | show_backtrace_past_entry (struct ui_file *file, int from_tty, | |
141 | struct cmd_list_element *c, const char *value) | |
142 | { | |
143 | fprintf_filtered (file, _("\ | |
144 | Whether backtraces should continue past the entry point of a program is %s.\n"), | |
145 | value); | |
146 | } | |
147 | ||
4a5e53e8 | 148 | static int backtrace_limit = INT_MAX; |
920d2a44 AC |
149 | static void |
150 | show_backtrace_limit (struct ui_file *file, int from_tty, | |
151 | struct cmd_list_element *c, const char *value) | |
152 | { | |
153 | fprintf_filtered (file, _("\ | |
154 | An upper bound on the number of backtrace levels is %s.\n"), | |
155 | value); | |
156 | } | |
157 | ||
eb4f72c5 | 158 | |
ca73dd9d AC |
159 | static void |
160 | fprint_field (struct ui_file *file, const char *name, int p, CORE_ADDR addr) | |
161 | { | |
162 | if (p) | |
163 | fprintf_unfiltered (file, "%s=0x%s", name, paddr_nz (addr)); | |
164 | else | |
165 | fprintf_unfiltered (file, "!%s", name); | |
166 | } | |
d65fe839 | 167 | |
00905d52 | 168 | void |
7f78e237 AC |
169 | fprint_frame_id (struct ui_file *file, struct frame_id id) |
170 | { | |
ca73dd9d AC |
171 | fprintf_unfiltered (file, "{"); |
172 | fprint_field (file, "stack", id.stack_addr_p, id.stack_addr); | |
173 | fprintf_unfiltered (file, ","); | |
174 | fprint_field (file, "code", id.code_addr_p, id.code_addr); | |
175 | fprintf_unfiltered (file, ","); | |
176 | fprint_field (file, "special", id.special_addr_p, id.special_addr); | |
177 | fprintf_unfiltered (file, "}"); | |
7f78e237 AC |
178 | } |
179 | ||
180 | static void | |
181 | fprint_frame_type (struct ui_file *file, enum frame_type type) | |
182 | { | |
183 | switch (type) | |
184 | { | |
7f78e237 AC |
185 | case NORMAL_FRAME: |
186 | fprintf_unfiltered (file, "NORMAL_FRAME"); | |
187 | return; | |
188 | case DUMMY_FRAME: | |
189 | fprintf_unfiltered (file, "DUMMY_FRAME"); | |
190 | return; | |
191 | case SIGTRAMP_FRAME: | |
192 | fprintf_unfiltered (file, "SIGTRAMP_FRAME"); | |
193 | return; | |
194 | default: | |
195 | fprintf_unfiltered (file, "<unknown type>"); | |
196 | return; | |
197 | }; | |
198 | } | |
199 | ||
200 | static void | |
201 | fprint_frame (struct ui_file *file, struct frame_info *fi) | |
202 | { | |
203 | if (fi == NULL) | |
204 | { | |
205 | fprintf_unfiltered (file, "<NULL frame>"); | |
206 | return; | |
207 | } | |
208 | fprintf_unfiltered (file, "{"); | |
209 | fprintf_unfiltered (file, "level=%d", fi->level); | |
210 | fprintf_unfiltered (file, ","); | |
211 | fprintf_unfiltered (file, "type="); | |
c1bf6f65 AC |
212 | if (fi->unwind != NULL) |
213 | fprint_frame_type (file, fi->unwind->type); | |
214 | else | |
215 | fprintf_unfiltered (file, "<unknown>"); | |
7f78e237 AC |
216 | fprintf_unfiltered (file, ","); |
217 | fprintf_unfiltered (file, "unwind="); | |
218 | if (fi->unwind != NULL) | |
219 | gdb_print_host_address (fi->unwind, file); | |
220 | else | |
221 | fprintf_unfiltered (file, "<unknown>"); | |
222 | fprintf_unfiltered (file, ","); | |
223 | fprintf_unfiltered (file, "pc="); | |
224 | if (fi->next != NULL && fi->next->prev_pc.p) | |
225 | fprintf_unfiltered (file, "0x%s", paddr_nz (fi->next->prev_pc.value)); | |
226 | else | |
227 | fprintf_unfiltered (file, "<unknown>"); | |
228 | fprintf_unfiltered (file, ","); | |
229 | fprintf_unfiltered (file, "id="); | |
230 | if (fi->this_id.p) | |
231 | fprint_frame_id (file, fi->this_id.value); | |
232 | else | |
233 | fprintf_unfiltered (file, "<unknown>"); | |
234 | fprintf_unfiltered (file, ","); | |
235 | fprintf_unfiltered (file, "func="); | |
236 | if (fi->next != NULL && fi->next->prev_func.p) | |
237 | fprintf_unfiltered (file, "0x%s", paddr_nz (fi->next->prev_func.addr)); | |
238 | else | |
239 | fprintf_unfiltered (file, "<unknown>"); | |
240 | fprintf_unfiltered (file, "}"); | |
241 | } | |
242 | ||
7a424e99 | 243 | /* Return a frame uniq ID that can be used to, later, re-find the |
101dcfbe AC |
244 | frame. */ |
245 | ||
7a424e99 AC |
246 | struct frame_id |
247 | get_frame_id (struct frame_info *fi) | |
101dcfbe AC |
248 | { |
249 | if (fi == NULL) | |
250 | { | |
7a424e99 | 251 | return null_frame_id; |
101dcfbe | 252 | } |
d0a55772 | 253 | if (!fi->this_id.p) |
101dcfbe | 254 | { |
7f78e237 AC |
255 | if (frame_debug) |
256 | fprintf_unfiltered (gdb_stdlog, "{ get_frame_id (fi=%d) ", | |
257 | fi->level); | |
c50901fd AC |
258 | /* Find the unwinder. */ |
259 | if (fi->unwind == NULL) | |
c1bf6f65 AC |
260 | fi->unwind = frame_unwind_find_by_frame (fi->next, |
261 | &fi->prologue_cache); | |
06c77151 | 262 | /* Find THIS frame's ID. */ |
d0a55772 AC |
263 | fi->unwind->this_id (fi->next, &fi->prologue_cache, &fi->this_id.value); |
264 | fi->this_id.p = 1; | |
7f78e237 AC |
265 | if (frame_debug) |
266 | { | |
267 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
268 | fprint_frame_id (gdb_stdlog, fi->this_id.value); | |
269 | fprintf_unfiltered (gdb_stdlog, " }\n"); | |
270 | } | |
101dcfbe | 271 | } |
18adea3f | 272 | return fi->this_id.value; |
101dcfbe AC |
273 | } |
274 | ||
5613d8d3 AC |
275 | struct frame_id |
276 | frame_unwind_id (struct frame_info *next_frame) | |
277 | { | |
278 | /* Use prev_frame, and not get_prev_frame. The latter will truncate | |
279 | the frame chain, leading to this function unintentionally | |
280 | returning a null_frame_id (e.g., when a caller requests the frame | |
281 | ID of "main()"s caller. */ | |
282 | return get_frame_id (get_prev_frame_1 (next_frame)); | |
283 | } | |
284 | ||
7a424e99 AC |
285 | const struct frame_id null_frame_id; /* All zeros. */ |
286 | ||
287 | struct frame_id | |
48c66725 JJ |
288 | frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr, |
289 | CORE_ADDR special_addr) | |
7a424e99 | 290 | { |
12b0b6de | 291 | struct frame_id id = null_frame_id; |
d0a55772 | 292 | id.stack_addr = stack_addr; |
12b0b6de | 293 | id.stack_addr_p = 1; |
d0a55772 | 294 | id.code_addr = code_addr; |
12b0b6de | 295 | id.code_addr_p = 1; |
48c66725 | 296 | id.special_addr = special_addr; |
12b0b6de | 297 | id.special_addr_p = 1; |
7a424e99 AC |
298 | return id; |
299 | } | |
300 | ||
48c66725 JJ |
301 | struct frame_id |
302 | frame_id_build (CORE_ADDR stack_addr, CORE_ADDR code_addr) | |
303 | { | |
12b0b6de UW |
304 | struct frame_id id = null_frame_id; |
305 | id.stack_addr = stack_addr; | |
306 | id.stack_addr_p = 1; | |
307 | id.code_addr = code_addr; | |
308 | id.code_addr_p = 1; | |
309 | return id; | |
310 | } | |
311 | ||
312 | struct frame_id | |
313 | frame_id_build_wild (CORE_ADDR stack_addr) | |
314 | { | |
315 | struct frame_id id = null_frame_id; | |
316 | id.stack_addr = stack_addr; | |
317 | id.stack_addr_p = 1; | |
318 | return id; | |
48c66725 JJ |
319 | } |
320 | ||
7a424e99 AC |
321 | int |
322 | frame_id_p (struct frame_id l) | |
323 | { | |
d0a55772 | 324 | int p; |
12b0b6de UW |
325 | /* The frame is valid iff it has a valid stack address. */ |
326 | p = l.stack_addr_p; | |
7f78e237 AC |
327 | if (frame_debug) |
328 | { | |
329 | fprintf_unfiltered (gdb_stdlog, "{ frame_id_p (l="); | |
330 | fprint_frame_id (gdb_stdlog, l); | |
331 | fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", p); | |
332 | } | |
d0a55772 | 333 | return p; |
7a424e99 AC |
334 | } |
335 | ||
336 | int | |
337 | frame_id_eq (struct frame_id l, struct frame_id r) | |
338 | { | |
d0a55772 | 339 | int eq; |
12b0b6de UW |
340 | if (!l.stack_addr_p || !r.stack_addr_p) |
341 | /* Like a NaN, if either ID is invalid, the result is false. | |
342 | Note that a frame ID is invalid iff it is the null frame ID. */ | |
d0a55772 AC |
343 | eq = 0; |
344 | else if (l.stack_addr != r.stack_addr) | |
345 | /* If .stack addresses are different, the frames are different. */ | |
346 | eq = 0; | |
12b0b6de UW |
347 | else if (!l.code_addr_p || !r.code_addr_p) |
348 | /* An invalid code addr is a wild card, always succeed. */ | |
d0a55772 | 349 | eq = 1; |
48c66725 JJ |
350 | else if (l.code_addr != r.code_addr) |
351 | /* If .code addresses are different, the frames are different. */ | |
352 | eq = 0; | |
12b0b6de UW |
353 | else if (!l.special_addr_p || !r.special_addr_p) |
354 | /* An invalid special addr is a wild card (or unused), always succeed. */ | |
48c66725 JJ |
355 | eq = 1; |
356 | else if (l.special_addr == r.special_addr) | |
357 | /* Frames are equal. */ | |
d0a55772 AC |
358 | eq = 1; |
359 | else | |
4aa79dcc AC |
360 | /* No luck. */ |
361 | eq = 0; | |
7f78e237 AC |
362 | if (frame_debug) |
363 | { | |
364 | fprintf_unfiltered (gdb_stdlog, "{ frame_id_eq (l="); | |
365 | fprint_frame_id (gdb_stdlog, l); | |
366 | fprintf_unfiltered (gdb_stdlog, ",r="); | |
367 | fprint_frame_id (gdb_stdlog, r); | |
368 | fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", eq); | |
369 | } | |
d0a55772 | 370 | return eq; |
7a424e99 AC |
371 | } |
372 | ||
373 | int | |
374 | frame_id_inner (struct frame_id l, struct frame_id r) | |
375 | { | |
d0a55772 | 376 | int inner; |
12b0b6de | 377 | if (!l.stack_addr_p || !r.stack_addr_p) |
d0a55772 AC |
378 | /* Like NaN, any operation involving an invalid ID always fails. */ |
379 | inner = 0; | |
380 | else | |
381 | /* Only return non-zero when strictly inner than. Note that, per | |
382 | comment in "frame.h", there is some fuzz here. Frameless | |
383 | functions are not strictly inner than (same .stack but | |
48c66725 | 384 | different .code and/or .special address). */ |
4d1e7dd1 | 385 | inner = gdbarch_inner_than (current_gdbarch, l.stack_addr, r.stack_addr); |
7f78e237 AC |
386 | if (frame_debug) |
387 | { | |
388 | fprintf_unfiltered (gdb_stdlog, "{ frame_id_inner (l="); | |
389 | fprint_frame_id (gdb_stdlog, l); | |
390 | fprintf_unfiltered (gdb_stdlog, ",r="); | |
391 | fprint_frame_id (gdb_stdlog, r); | |
392 | fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", inner); | |
393 | } | |
d0a55772 | 394 | return inner; |
7a424e99 AC |
395 | } |
396 | ||
101dcfbe AC |
397 | struct frame_info * |
398 | frame_find_by_id (struct frame_id id) | |
399 | { | |
400 | struct frame_info *frame; | |
401 | ||
402 | /* ZERO denotes the null frame, let the caller decide what to do | |
403 | about it. Should it instead return get_current_frame()? */ | |
7a424e99 | 404 | if (!frame_id_p (id)) |
101dcfbe AC |
405 | return NULL; |
406 | ||
407 | for (frame = get_current_frame (); | |
408 | frame != NULL; | |
409 | frame = get_prev_frame (frame)) | |
410 | { | |
7a424e99 AC |
411 | struct frame_id this = get_frame_id (frame); |
412 | if (frame_id_eq (id, this)) | |
413 | /* An exact match. */ | |
414 | return frame; | |
415 | if (frame_id_inner (id, this)) | |
416 | /* Gone to far. */ | |
101dcfbe | 417 | return NULL; |
bbde78fa JM |
418 | /* Either we're not yet gone far enough out along the frame |
419 | chain (inner(this,id)), or we're comparing frameless functions | |
7a424e99 AC |
420 | (same .base, different .func, no test available). Struggle |
421 | on until we've definitly gone to far. */ | |
101dcfbe AC |
422 | } |
423 | return NULL; | |
424 | } | |
425 | ||
f18c5a73 | 426 | CORE_ADDR |
12cc2063 | 427 | frame_pc_unwind (struct frame_info *this_frame) |
f18c5a73 | 428 | { |
d1340264 | 429 | if (!this_frame->prev_pc.p) |
f18c5a73 | 430 | { |
12cc2063 | 431 | CORE_ADDR pc; |
cbafadeb AC |
432 | if (this_frame->unwind == NULL) |
433 | this_frame->unwind | |
434 | = frame_unwind_find_by_frame (this_frame->next, | |
435 | &this_frame->prologue_cache); | |
436 | if (this_frame->unwind->prev_pc != NULL) | |
437 | /* A per-frame unwinder, prefer it. */ | |
438 | pc = this_frame->unwind->prev_pc (this_frame->next, | |
439 | &this_frame->prologue_cache); | |
440 | else if (gdbarch_unwind_pc_p (current_gdbarch)) | |
12cc2063 AC |
441 | { |
442 | /* The right way. The `pure' way. The one true way. This | |
443 | method depends solely on the register-unwind code to | |
444 | determine the value of registers in THIS frame, and hence | |
445 | the value of this frame's PC (resume address). A typical | |
446 | implementation is no more than: | |
447 | ||
448 | frame_unwind_register (this_frame, ISA_PC_REGNUM, buf); | |
af1342ab | 449 | return extract_unsigned_integer (buf, size of ISA_PC_REGNUM); |
12cc2063 AC |
450 | |
451 | Note: this method is very heavily dependent on a correct | |
452 | register-unwind implementation, it pays to fix that | |
453 | method first; this method is frame type agnostic, since | |
454 | it only deals with register values, it works with any | |
455 | frame. This is all in stark contrast to the old | |
456 | FRAME_SAVED_PC which would try to directly handle all the | |
457 | different ways that a PC could be unwound. */ | |
458 | pc = gdbarch_unwind_pc (current_gdbarch, this_frame); | |
459 | } | |
12cc2063 | 460 | else |
e2e0b3e5 | 461 | internal_error (__FILE__, __LINE__, _("No unwind_pc method")); |
d1340264 AC |
462 | this_frame->prev_pc.value = pc; |
463 | this_frame->prev_pc.p = 1; | |
7f78e237 AC |
464 | if (frame_debug) |
465 | fprintf_unfiltered (gdb_stdlog, | |
466 | "{ frame_pc_unwind (this_frame=%d) -> 0x%s }\n", | |
467 | this_frame->level, | |
468 | paddr_nz (this_frame->prev_pc.value)); | |
f18c5a73 | 469 | } |
d1340264 | 470 | return this_frame->prev_pc.value; |
f18c5a73 AC |
471 | } |
472 | ||
be41e9f4 | 473 | CORE_ADDR |
93d42b30 | 474 | frame_func_unwind (struct frame_info *fi, enum frame_type this_type) |
be41e9f4 AC |
475 | { |
476 | if (!fi->prev_func.p) | |
477 | { | |
57bfe177 AC |
478 | /* Make certain that this, and not the adjacent, function is |
479 | found. */ | |
93d42b30 | 480 | CORE_ADDR addr_in_block = frame_unwind_address_in_block (fi, this_type); |
be41e9f4 | 481 | fi->prev_func.p = 1; |
57bfe177 | 482 | fi->prev_func.addr = get_pc_function_start (addr_in_block); |
7f78e237 AC |
483 | if (frame_debug) |
484 | fprintf_unfiltered (gdb_stdlog, | |
485 | "{ frame_func_unwind (fi=%d) -> 0x%s }\n", | |
486 | fi->level, paddr_nz (fi->prev_func.addr)); | |
be41e9f4 AC |
487 | } |
488 | return fi->prev_func.addr; | |
489 | } | |
490 | ||
491 | CORE_ADDR | |
492 | get_frame_func (struct frame_info *fi) | |
493 | { | |
93d42b30 | 494 | return frame_func_unwind (fi->next, get_frame_type (fi)); |
be41e9f4 AC |
495 | } |
496 | ||
7a25a7c1 | 497 | static int |
2d522557 | 498 | do_frame_register_read (void *src, int regnum, gdb_byte *buf) |
7a25a7c1 | 499 | { |
a81dcb05 | 500 | frame_register_read (src, regnum, buf); |
7a25a7c1 AC |
501 | return 1; |
502 | } | |
503 | ||
a81dcb05 AC |
504 | struct regcache * |
505 | frame_save_as_regcache (struct frame_info *this_frame) | |
506 | { | |
507 | struct regcache *regcache = regcache_xmalloc (current_gdbarch); | |
508 | struct cleanup *cleanups = make_cleanup_regcache_xfree (regcache); | |
509 | regcache_save (regcache, do_frame_register_read, this_frame); | |
510 | discard_cleanups (cleanups); | |
511 | return regcache; | |
512 | } | |
513 | ||
dbe9fe58 | 514 | void |
7a25a7c1 AC |
515 | frame_pop (struct frame_info *this_frame) |
516 | { | |
348473d5 NF |
517 | struct frame_info *prev_frame; |
518 | struct regcache *scratch; | |
519 | struct cleanup *cleanups; | |
520 | ||
521 | /* Ensure that we have a frame to pop to. */ | |
522 | prev_frame = get_prev_frame_1 (this_frame); | |
523 | ||
524 | if (!prev_frame) | |
525 | error (_("Cannot pop the initial frame.")); | |
526 | ||
c1bf6f65 AC |
527 | /* Make a copy of all the register values unwound from this frame. |
528 | Save them in a scratch buffer so that there isn't a race between | |
529 | trying to extract the old values from the current_regcache while | |
530 | at the same time writing new values into that same cache. */ | |
348473d5 NF |
531 | scratch = frame_save_as_regcache (prev_frame); |
532 | cleanups = make_cleanup_regcache_xfree (scratch); | |
c1bf6f65 AC |
533 | |
534 | /* FIXME: cagney/2003-03-16: It should be possible to tell the | |
535 | target's register cache that it is about to be hit with a burst | |
536 | register transfer and that the sequence of register writes should | |
537 | be batched. The pair target_prepare_to_store() and | |
538 | target_store_registers() kind of suggest this functionality. | |
539 | Unfortunately, they don't implement it. Their lack of a formal | |
540 | definition can lead to targets writing back bogus values | |
541 | (arguably a bug in the target code mind). */ | |
542 | /* Now copy those saved registers into the current regcache. | |
543 | Here, regcache_cpy() calls regcache_restore(). */ | |
544 | regcache_cpy (current_regcache, scratch); | |
545 | do_cleanups (cleanups); | |
7a25a7c1 | 546 | |
7a25a7c1 AC |
547 | /* We've made right mess of GDB's local state, just discard |
548 | everything. */ | |
35f196d9 | 549 | reinit_frame_cache (); |
dbe9fe58 | 550 | } |
c689142b | 551 | |
4f460812 AC |
552 | void |
553 | frame_register_unwind (struct frame_info *frame, int regnum, | |
554 | int *optimizedp, enum lval_type *lvalp, | |
10c42a71 | 555 | CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp) |
4f460812 AC |
556 | { |
557 | struct frame_unwind_cache *cache; | |
558 | ||
7f78e237 AC |
559 | if (frame_debug) |
560 | { | |
6764ddad AC |
561 | fprintf_unfiltered (gdb_stdlog, "\ |
562 | { frame_register_unwind (frame=%d,regnum=%d(%s),...) ", | |
563 | frame->level, regnum, | |
564 | frame_map_regnum_to_name (frame, regnum)); | |
7f78e237 AC |
565 | } |
566 | ||
4f460812 AC |
567 | /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates |
568 | that the value proper does not need to be fetched. */ | |
569 | gdb_assert (optimizedp != NULL); | |
570 | gdb_assert (lvalp != NULL); | |
571 | gdb_assert (addrp != NULL); | |
572 | gdb_assert (realnump != NULL); | |
573 | /* gdb_assert (bufferp != NULL); */ | |
574 | ||
a94dd1fd AC |
575 | /* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame |
576 | is broken. There is always a frame. If there, for some reason, | |
bbde78fa | 577 | isn't a frame, there is some pretty busted code as it should have |
a94dd1fd AC |
578 | detected the problem before calling here. */ |
579 | gdb_assert (frame != NULL); | |
4f460812 | 580 | |
c50901fd AC |
581 | /* Find the unwinder. */ |
582 | if (frame->unwind == NULL) | |
c1bf6f65 AC |
583 | frame->unwind = frame_unwind_find_by_frame (frame->next, |
584 | &frame->prologue_cache); | |
c50901fd | 585 | |
6dc42492 | 586 | /* Ask this frame to unwind its register. See comment in |
bbde78fa | 587 | "frame-unwind.h" for why NEXT frame and this unwind cache are |
6dc42492 AC |
588 | passed in. */ |
589 | frame->unwind->prev_register (frame->next, &frame->prologue_cache, regnum, | |
590 | optimizedp, lvalp, addrp, realnump, bufferp); | |
591 | ||
7f78e237 AC |
592 | if (frame_debug) |
593 | { | |
594 | fprintf_unfiltered (gdb_stdlog, "->"); | |
595 | fprintf_unfiltered (gdb_stdlog, " *optimizedp=%d", (*optimizedp)); | |
596 | fprintf_unfiltered (gdb_stdlog, " *lvalp=%d", (int) (*lvalp)); | |
597 | fprintf_unfiltered (gdb_stdlog, " *addrp=0x%s", paddr_nz ((*addrp))); | |
598 | fprintf_unfiltered (gdb_stdlog, " *bufferp="); | |
599 | if (bufferp == NULL) | |
600 | fprintf_unfiltered (gdb_stdlog, "<NULL>"); | |
601 | else | |
602 | { | |
603 | int i; | |
d2cf594a | 604 | const unsigned char *buf = bufferp; |
7f78e237 AC |
605 | fprintf_unfiltered (gdb_stdlog, "["); |
606 | for (i = 0; i < register_size (current_gdbarch, regnum); i++) | |
607 | fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]); | |
608 | fprintf_unfiltered (gdb_stdlog, "]"); | |
609 | } | |
610 | fprintf_unfiltered (gdb_stdlog, " }\n"); | |
611 | } | |
4f460812 AC |
612 | } |
613 | ||
a216a322 AC |
614 | void |
615 | frame_register (struct frame_info *frame, int regnum, | |
616 | int *optimizedp, enum lval_type *lvalp, | |
10c42a71 | 617 | CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp) |
a216a322 AC |
618 | { |
619 | /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates | |
620 | that the value proper does not need to be fetched. */ | |
621 | gdb_assert (optimizedp != NULL); | |
622 | gdb_assert (lvalp != NULL); | |
623 | gdb_assert (addrp != NULL); | |
624 | gdb_assert (realnump != NULL); | |
625 | /* gdb_assert (bufferp != NULL); */ | |
626 | ||
a94dd1fd AC |
627 | /* Obtain the register value by unwinding the register from the next |
628 | (more inner frame). */ | |
629 | gdb_assert (frame != NULL && frame->next != NULL); | |
630 | frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp, | |
631 | realnump, bufferp); | |
a216a322 AC |
632 | } |
633 | ||
135c175f | 634 | void |
10c42a71 | 635 | frame_unwind_register (struct frame_info *frame, int regnum, gdb_byte *buf) |
135c175f AC |
636 | { |
637 | int optimized; | |
638 | CORE_ADDR addr; | |
639 | int realnum; | |
640 | enum lval_type lval; | |
135c175f AC |
641 | frame_register_unwind (frame, regnum, &optimized, &lval, &addr, |
642 | &realnum, buf); | |
5b181d62 AC |
643 | } |
644 | ||
f0e7d0e8 AC |
645 | void |
646 | get_frame_register (struct frame_info *frame, | |
10c42a71 | 647 | int regnum, gdb_byte *buf) |
f0e7d0e8 AC |
648 | { |
649 | frame_unwind_register (frame->next, regnum, buf); | |
650 | } | |
651 | ||
652 | LONGEST | |
653 | frame_unwind_register_signed (struct frame_info *frame, int regnum) | |
654 | { | |
10c42a71 | 655 | gdb_byte buf[MAX_REGISTER_SIZE]; |
f0e7d0e8 | 656 | frame_unwind_register (frame, regnum, buf); |
5bc602c7 AC |
657 | return extract_signed_integer (buf, register_size (get_frame_arch (frame), |
658 | regnum)); | |
f0e7d0e8 AC |
659 | } |
660 | ||
661 | LONGEST | |
662 | get_frame_register_signed (struct frame_info *frame, int regnum) | |
663 | { | |
664 | return frame_unwind_register_signed (frame->next, regnum); | |
665 | } | |
666 | ||
667 | ULONGEST | |
668 | frame_unwind_register_unsigned (struct frame_info *frame, int regnum) | |
669 | { | |
10c42a71 | 670 | gdb_byte buf[MAX_REGISTER_SIZE]; |
f0e7d0e8 | 671 | frame_unwind_register (frame, regnum, buf); |
5bc602c7 AC |
672 | return extract_unsigned_integer (buf, register_size (get_frame_arch (frame), |
673 | regnum)); | |
f0e7d0e8 AC |
674 | } |
675 | ||
676 | ULONGEST | |
677 | get_frame_register_unsigned (struct frame_info *frame, int regnum) | |
678 | { | |
679 | return frame_unwind_register_unsigned (frame->next, regnum); | |
680 | } | |
681 | ||
135c175f AC |
682 | void |
683 | frame_unwind_unsigned_register (struct frame_info *frame, int regnum, | |
684 | ULONGEST *val) | |
685 | { | |
10c42a71 | 686 | gdb_byte buf[MAX_REGISTER_SIZE]; |
5b181d62 | 687 | frame_unwind_register (frame, regnum, buf); |
5bc602c7 AC |
688 | (*val) = extract_unsigned_integer (buf, |
689 | register_size (get_frame_arch (frame), | |
690 | regnum)); | |
135c175f | 691 | } |
4f460812 | 692 | |
ff2e87ac | 693 | void |
10c42a71 AC |
694 | put_frame_register (struct frame_info *frame, int regnum, |
695 | const gdb_byte *buf) | |
ff2e87ac AC |
696 | { |
697 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
698 | int realnum; | |
699 | int optim; | |
700 | enum lval_type lval; | |
701 | CORE_ADDR addr; | |
702 | frame_register (frame, regnum, &optim, &lval, &addr, &realnum, NULL); | |
703 | if (optim) | |
8a3fe4f8 | 704 | error (_("Attempt to assign to a value that was optimized out.")); |
ff2e87ac AC |
705 | switch (lval) |
706 | { | |
707 | case lval_memory: | |
708 | { | |
709 | /* FIXME: write_memory doesn't yet take constant buffers. | |
710 | Arrrg! */ | |
10c42a71 | 711 | gdb_byte tmp[MAX_REGISTER_SIZE]; |
ff2e87ac AC |
712 | memcpy (tmp, buf, register_size (gdbarch, regnum)); |
713 | write_memory (addr, tmp, register_size (gdbarch, regnum)); | |
714 | break; | |
715 | } | |
716 | case lval_register: | |
717 | regcache_cooked_write (current_regcache, realnum, buf); | |
718 | break; | |
719 | default: | |
8a3fe4f8 | 720 | error (_("Attempt to assign to an unmodifiable value.")); |
ff2e87ac AC |
721 | } |
722 | } | |
723 | ||
cda5a58a | 724 | /* frame_register_read () |
d65fe839 | 725 | |
cda5a58a | 726 | Find and return the value of REGNUM for the specified stack frame. |
5bc602c7 | 727 | The number of bytes copied is REGISTER_SIZE (REGNUM). |
d65fe839 | 728 | |
cda5a58a | 729 | Returns 0 if the register value could not be found. */ |
d65fe839 | 730 | |
cda5a58a | 731 | int |
10c42a71 AC |
732 | frame_register_read (struct frame_info *frame, int regnum, |
733 | gdb_byte *myaddr) | |
d65fe839 | 734 | { |
a216a322 AC |
735 | int optimized; |
736 | enum lval_type lval; | |
737 | CORE_ADDR addr; | |
738 | int realnum; | |
739 | frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr); | |
d65fe839 | 740 | |
a216a322 | 741 | return !optimized; |
d65fe839 | 742 | } |
e36180d7 | 743 | |
00fa51f6 UW |
744 | int |
745 | get_frame_register_bytes (struct frame_info *frame, int regnum, | |
746 | CORE_ADDR offset, int len, gdb_byte *myaddr) | |
747 | { | |
748 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
749 | ||
750 | /* Skip registers wholly inside of OFFSET. */ | |
751 | while (offset >= register_size (gdbarch, regnum)) | |
752 | { | |
753 | offset -= register_size (gdbarch, regnum); | |
754 | regnum++; | |
755 | } | |
756 | ||
757 | /* Copy the data. */ | |
758 | while (len > 0) | |
759 | { | |
760 | int curr_len = register_size (gdbarch, regnum) - offset; | |
761 | if (curr_len > len) | |
762 | curr_len = len; | |
763 | ||
764 | if (curr_len == register_size (gdbarch, regnum)) | |
765 | { | |
766 | if (!frame_register_read (frame, regnum, myaddr)) | |
767 | return 0; | |
768 | } | |
769 | else | |
770 | { | |
771 | gdb_byte buf[MAX_REGISTER_SIZE]; | |
772 | if (!frame_register_read (frame, regnum, buf)) | |
773 | return 0; | |
774 | memcpy (myaddr, buf + offset, curr_len); | |
775 | } | |
776 | ||
765f065a | 777 | myaddr += curr_len; |
00fa51f6 UW |
778 | len -= curr_len; |
779 | offset = 0; | |
780 | regnum++; | |
781 | } | |
782 | ||
783 | return 1; | |
784 | } | |
785 | ||
786 | void | |
787 | put_frame_register_bytes (struct frame_info *frame, int regnum, | |
788 | CORE_ADDR offset, int len, const gdb_byte *myaddr) | |
789 | { | |
790 | struct gdbarch *gdbarch = get_frame_arch (frame); | |
791 | ||
792 | /* Skip registers wholly inside of OFFSET. */ | |
793 | while (offset >= register_size (gdbarch, regnum)) | |
794 | { | |
795 | offset -= register_size (gdbarch, regnum); | |
796 | regnum++; | |
797 | } | |
798 | ||
799 | /* Copy the data. */ | |
800 | while (len > 0) | |
801 | { | |
802 | int curr_len = register_size (gdbarch, regnum) - offset; | |
803 | if (curr_len > len) | |
804 | curr_len = len; | |
805 | ||
806 | if (curr_len == register_size (gdbarch, regnum)) | |
807 | { | |
808 | put_frame_register (frame, regnum, myaddr); | |
809 | } | |
810 | else | |
811 | { | |
812 | gdb_byte buf[MAX_REGISTER_SIZE]; | |
813 | frame_register_read (frame, regnum, buf); | |
814 | memcpy (buf + offset, myaddr, curr_len); | |
815 | put_frame_register (frame, regnum, buf); | |
816 | } | |
817 | ||
765f065a | 818 | myaddr += curr_len; |
00fa51f6 UW |
819 | len -= curr_len; |
820 | offset = 0; | |
821 | regnum++; | |
822 | } | |
823 | } | |
e36180d7 AC |
824 | |
825 | /* Map between a frame register number and its name. A frame register | |
826 | space is a superset of the cooked register space --- it also | |
827 | includes builtin registers. */ | |
828 | ||
829 | int | |
eb8bc282 | 830 | frame_map_name_to_regnum (struct frame_info *frame, const char *name, int len) |
e36180d7 | 831 | { |
eb8bc282 | 832 | return user_reg_map_name_to_regnum (get_frame_arch (frame), name, len); |
e36180d7 AC |
833 | } |
834 | ||
835 | const char * | |
eb8bc282 | 836 | frame_map_regnum_to_name (struct frame_info *frame, int regnum) |
e36180d7 | 837 | { |
eb8bc282 | 838 | return user_reg_map_regnum_to_name (get_frame_arch (frame), regnum); |
e36180d7 | 839 | } |
4c1e7e9d | 840 | |
a94dd1fd AC |
841 | /* Create a sentinel frame. */ |
842 | ||
b9362cc7 | 843 | static struct frame_info * |
a94dd1fd AC |
844 | create_sentinel_frame (struct regcache *regcache) |
845 | { | |
846 | struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info); | |
a94dd1fd AC |
847 | frame->level = -1; |
848 | /* Explicitly initialize the sentinel frame's cache. Provide it | |
849 | with the underlying regcache. In the future additional | |
850 | information, such as the frame's thread will be added. */ | |
6dc42492 | 851 | frame->prologue_cache = sentinel_frame_cache (regcache); |
a94dd1fd AC |
852 | /* For the moment there is only one sentinel frame implementation. */ |
853 | frame->unwind = sentinel_frame_unwind; | |
854 | /* Link this frame back to itself. The frame is self referential | |
855 | (the unwound PC is the same as the pc), so make it so. */ | |
856 | frame->next = frame; | |
50bbdbd9 AC |
857 | /* Make the sentinel frame's ID valid, but invalid. That way all |
858 | comparisons with it should fail. */ | |
d0a55772 AC |
859 | frame->this_id.p = 1; |
860 | frame->this_id.value = null_frame_id; | |
7f78e237 AC |
861 | if (frame_debug) |
862 | { | |
863 | fprintf_unfiltered (gdb_stdlog, "{ create_sentinel_frame (...) -> "); | |
864 | fprint_frame (gdb_stdlog, frame); | |
865 | fprintf_unfiltered (gdb_stdlog, " }\n"); | |
866 | } | |
a94dd1fd AC |
867 | return frame; |
868 | } | |
869 | ||
4c1e7e9d AC |
870 | /* Info about the innermost stack frame (contents of FP register) */ |
871 | ||
872 | static struct frame_info *current_frame; | |
873 | ||
874 | /* Cache for frame addresses already read by gdb. Valid only while | |
875 | inferior is stopped. Control variables for the frame cache should | |
876 | be local to this module. */ | |
877 | ||
878 | static struct obstack frame_cache_obstack; | |
879 | ||
880 | void * | |
479ab5a0 | 881 | frame_obstack_zalloc (unsigned long size) |
4c1e7e9d | 882 | { |
479ab5a0 AC |
883 | void *data = obstack_alloc (&frame_cache_obstack, size); |
884 | memset (data, 0, size); | |
885 | return data; | |
4c1e7e9d AC |
886 | } |
887 | ||
a94dd1fd AC |
888 | /* Return the innermost (currently executing) stack frame. This is |
889 | split into two functions. The function unwind_to_current_frame() | |
890 | is wrapped in catch exceptions so that, even when the unwind of the | |
891 | sentinel frame fails, the function still returns a stack frame. */ | |
892 | ||
893 | static int | |
894 | unwind_to_current_frame (struct ui_out *ui_out, void *args) | |
895 | { | |
896 | struct frame_info *frame = get_prev_frame (args); | |
bbde78fa | 897 | /* A sentinel frame can fail to unwind, e.g., because its PC value |
a94dd1fd AC |
898 | lands in somewhere like start. */ |
899 | if (frame == NULL) | |
900 | return 1; | |
901 | current_frame = frame; | |
902 | return 0; | |
903 | } | |
4c1e7e9d AC |
904 | |
905 | struct frame_info * | |
906 | get_current_frame (void) | |
907 | { | |
0a1e1ca1 AC |
908 | /* First check, and report, the lack of registers. Having GDB |
909 | report "No stack!" or "No memory" when the target doesn't even | |
910 | have registers is very confusing. Besides, "printcmd.exp" | |
911 | explicitly checks that ``print $pc'' with no registers prints "No | |
912 | registers". */ | |
a94dd1fd | 913 | if (!target_has_registers) |
8a3fe4f8 | 914 | error (_("No registers.")); |
0a1e1ca1 | 915 | if (!target_has_stack) |
8a3fe4f8 | 916 | error (_("No stack.")); |
a94dd1fd | 917 | if (!target_has_memory) |
8a3fe4f8 | 918 | error (_("No memory.")); |
4c1e7e9d AC |
919 | if (current_frame == NULL) |
920 | { | |
a94dd1fd AC |
921 | struct frame_info *sentinel_frame = |
922 | create_sentinel_frame (current_regcache); | |
923 | if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame, | |
1c3c7ee7 | 924 | RETURN_MASK_ERROR) != 0) |
a94dd1fd AC |
925 | { |
926 | /* Oops! Fake a current frame? Is this useful? It has a PC | |
927 | of zero, for instance. */ | |
928 | current_frame = sentinel_frame; | |
929 | } | |
4c1e7e9d AC |
930 | } |
931 | return current_frame; | |
932 | } | |
933 | ||
6e7f8b9c AC |
934 | /* The "selected" stack frame is used by default for local and arg |
935 | access. May be zero, for no selected frame. */ | |
936 | ||
206415a3 | 937 | static struct frame_info *selected_frame; |
6e7f8b9c | 938 | |
bbde78fa | 939 | /* Return the selected frame. Always non-NULL (unless there isn't an |
6e7f8b9c AC |
940 | inferior sufficient for creating a frame) in which case an error is |
941 | thrown. */ | |
942 | ||
943 | struct frame_info * | |
b04f3ab4 | 944 | get_selected_frame (const char *message) |
6e7f8b9c | 945 | { |
206415a3 | 946 | if (selected_frame == NULL) |
b04f3ab4 AC |
947 | { |
948 | if (message != NULL && (!target_has_registers | |
949 | || !target_has_stack | |
950 | || !target_has_memory)) | |
8a3fe4f8 | 951 | error (("%s"), message); |
b04f3ab4 AC |
952 | /* Hey! Don't trust this. It should really be re-finding the |
953 | last selected frame of the currently selected thread. This, | |
954 | though, is better than nothing. */ | |
955 | select_frame (get_current_frame ()); | |
956 | } | |
6e7f8b9c | 957 | /* There is always a frame. */ |
206415a3 DJ |
958 | gdb_assert (selected_frame != NULL); |
959 | return selected_frame; | |
6e7f8b9c AC |
960 | } |
961 | ||
bbde78fa | 962 | /* This is a variant of get_selected_frame() which can be called when |
7dd88986 | 963 | the inferior does not have a frame; in that case it will return |
bbde78fa | 964 | NULL instead of calling error(). */ |
7dd88986 DJ |
965 | |
966 | struct frame_info * | |
967 | deprecated_safe_get_selected_frame (void) | |
968 | { | |
969 | if (!target_has_registers || !target_has_stack || !target_has_memory) | |
970 | return NULL; | |
b04f3ab4 | 971 | return get_selected_frame (NULL); |
7dd88986 DJ |
972 | } |
973 | ||
6e7f8b9c AC |
974 | /* Select frame FI (or NULL - to invalidate the current frame). */ |
975 | ||
976 | void | |
977 | select_frame (struct frame_info *fi) | |
978 | { | |
52f0bd74 | 979 | struct symtab *s; |
6e7f8b9c | 980 | |
206415a3 | 981 | selected_frame = fi; |
bbde78fa | 982 | /* NOTE: cagney/2002-05-04: FI can be NULL. This occurs when the |
6e7f8b9c | 983 | frame is being invalidated. */ |
9a4105ab AC |
984 | if (deprecated_selected_frame_level_changed_hook) |
985 | deprecated_selected_frame_level_changed_hook (frame_relative_level (fi)); | |
6e7f8b9c AC |
986 | |
987 | /* FIXME: kseitz/2002-08-28: It would be nice to call | |
bbde78fa | 988 | selected_frame_level_changed_event() right here, but due to limitations |
6e7f8b9c | 989 | in the current interfaces, we would end up flooding UIs with events |
bbde78fa | 990 | because select_frame() is used extensively internally. |
6e7f8b9c AC |
991 | |
992 | Once we have frame-parameterized frame (and frame-related) commands, | |
993 | the event notification can be moved here, since this function will only | |
bbde78fa | 994 | be called when the user's selected frame is being changed. */ |
6e7f8b9c AC |
995 | |
996 | /* Ensure that symbols for this frame are read in. Also, determine the | |
997 | source language of this frame, and switch to it if desired. */ | |
998 | if (fi) | |
999 | { | |
7ae4c3a5 | 1000 | /* We retrieve the frame's symtab by using the frame PC. However |
bbde78fa | 1001 | we cannot use the frame PC as-is, because it usually points to |
7ae4c3a5 JB |
1002 | the instruction following the "call", which is sometimes the |
1003 | first instruction of another function. So we rely on | |
1004 | get_frame_address_in_block() which provides us with a PC which | |
1005 | is guaranteed to be inside the frame's code block. */ | |
1006 | s = find_pc_symtab (get_frame_address_in_block (fi)); | |
6e7f8b9c AC |
1007 | if (s |
1008 | && s->language != current_language->la_language | |
1009 | && s->language != language_unknown | |
1010 | && language_mode == language_mode_auto) | |
1011 | { | |
1012 | set_language (s->language); | |
1013 | } | |
1014 | } | |
1015 | } | |
c689142b | 1016 | |
4c1e7e9d AC |
1017 | /* Create an arbitrary (i.e. address specified by user) or innermost frame. |
1018 | Always returns a non-NULL value. */ | |
1019 | ||
1020 | struct frame_info * | |
1021 | create_new_frame (CORE_ADDR addr, CORE_ADDR pc) | |
1022 | { | |
1023 | struct frame_info *fi; | |
4c1e7e9d | 1024 | |
7f78e237 AC |
1025 | if (frame_debug) |
1026 | { | |
1027 | fprintf_unfiltered (gdb_stdlog, | |
1028 | "{ create_new_frame (addr=0x%s, pc=0x%s) ", | |
1029 | paddr_nz (addr), paddr_nz (pc)); | |
1030 | } | |
1031 | ||
35d5d4ee | 1032 | fi = FRAME_OBSTACK_ZALLOC (struct frame_info); |
4c1e7e9d | 1033 | |
a94dd1fd | 1034 | fi->next = create_sentinel_frame (current_regcache); |
7df05f2b AC |
1035 | |
1036 | /* Select/initialize both the unwind function and the frame's type | |
1037 | based on the PC. */ | |
82417da5 | 1038 | fi->unwind = frame_unwind_find_by_frame (fi->next, &fi->prologue_cache); |
7df05f2b | 1039 | |
18adea3f | 1040 | fi->this_id.p = 1; |
11889732 AC |
1041 | deprecated_update_frame_base_hack (fi, addr); |
1042 | deprecated_update_frame_pc_hack (fi, pc); | |
4c1e7e9d | 1043 | |
7f78e237 AC |
1044 | if (frame_debug) |
1045 | { | |
1046 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
1047 | fprint_frame (gdb_stdlog, fi); | |
1048 | fprintf_unfiltered (gdb_stdlog, " }\n"); | |
1049 | } | |
1050 | ||
4c1e7e9d AC |
1051 | return fi; |
1052 | } | |
1053 | ||
03febf99 AC |
1054 | /* Return the frame that THIS_FRAME calls (NULL if THIS_FRAME is the |
1055 | innermost frame). Be careful to not fall off the bottom of the | |
1056 | frame chain and onto the sentinel frame. */ | |
4c1e7e9d AC |
1057 | |
1058 | struct frame_info * | |
03febf99 | 1059 | get_next_frame (struct frame_info *this_frame) |
4c1e7e9d | 1060 | { |
03febf99 AC |
1061 | if (this_frame->level > 0) |
1062 | return this_frame->next; | |
a94dd1fd AC |
1063 | else |
1064 | return NULL; | |
4c1e7e9d AC |
1065 | } |
1066 | ||
f4c5303c OF |
1067 | /* Observer for the target_changed event. */ |
1068 | ||
1069 | void | |
1070 | frame_observer_target_changed (struct target_ops *target) | |
1071 | { | |
35f196d9 | 1072 | reinit_frame_cache (); |
f4c5303c OF |
1073 | } |
1074 | ||
4c1e7e9d AC |
1075 | /* Flush the entire frame cache. */ |
1076 | ||
1077 | void | |
35f196d9 | 1078 | reinit_frame_cache (void) |
4c1e7e9d AC |
1079 | { |
1080 | /* Since we can't really be sure what the first object allocated was */ | |
1081 | obstack_free (&frame_cache_obstack, 0); | |
1082 | obstack_init (&frame_cache_obstack); | |
1083 | ||
1084 | current_frame = NULL; /* Invalidate cache */ | |
1085 | select_frame (NULL); | |
1086 | annotate_frames_invalid (); | |
7f78e237 | 1087 | if (frame_debug) |
35f196d9 | 1088 | fprintf_unfiltered (gdb_stdlog, "{ reinit_frame_cache () }\n"); |
4c1e7e9d AC |
1089 | } |
1090 | ||
e48af409 DJ |
1091 | /* Find where a register is saved (in memory or another register). |
1092 | The result of frame_register_unwind is just where it is saved | |
5efde112 | 1093 | relative to this particular frame. */ |
e48af409 DJ |
1094 | |
1095 | static void | |
1096 | frame_register_unwind_location (struct frame_info *this_frame, int regnum, | |
1097 | int *optimizedp, enum lval_type *lvalp, | |
1098 | CORE_ADDR *addrp, int *realnump) | |
1099 | { | |
1100 | gdb_assert (this_frame == NULL || this_frame->level >= 0); | |
1101 | ||
1102 | while (this_frame != NULL) | |
1103 | { | |
1104 | frame_register_unwind (this_frame, regnum, optimizedp, lvalp, | |
1105 | addrp, realnump, NULL); | |
1106 | ||
1107 | if (*optimizedp) | |
1108 | break; | |
1109 | ||
1110 | if (*lvalp != lval_register) | |
1111 | break; | |
1112 | ||
1113 | regnum = *realnump; | |
1114 | this_frame = get_next_frame (this_frame); | |
1115 | } | |
1116 | } | |
1117 | ||
5613d8d3 AC |
1118 | /* Return a "struct frame_info" corresponding to the frame that called |
1119 | THIS_FRAME. Returns NULL if there is no such frame. | |
5bf00f29 | 1120 | |
5613d8d3 AC |
1121 | Unlike get_prev_frame, this function always tries to unwind the |
1122 | frame. */ | |
eb4f72c5 | 1123 | |
5613d8d3 AC |
1124 | static struct frame_info * |
1125 | get_prev_frame_1 (struct frame_info *this_frame) | |
eb4f72c5 AC |
1126 | { |
1127 | struct frame_info *prev_frame; | |
756e95f1 | 1128 | struct frame_id this_id; |
eb4f72c5 | 1129 | |
5613d8d3 AC |
1130 | gdb_assert (this_frame != NULL); |
1131 | ||
7f78e237 AC |
1132 | if (frame_debug) |
1133 | { | |
5613d8d3 | 1134 | fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame_1 (this_frame="); |
7f78e237 AC |
1135 | if (this_frame != NULL) |
1136 | fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level); | |
1137 | else | |
1138 | fprintf_unfiltered (gdb_stdlog, "<NULL>"); | |
1139 | fprintf_unfiltered (gdb_stdlog, ") "); | |
1140 | } | |
1141 | ||
5613d8d3 AC |
1142 | /* Only try to do the unwind once. */ |
1143 | if (this_frame->prev_p) | |
1144 | { | |
1145 | if (frame_debug) | |
1146 | { | |
1147 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
1148 | fprint_frame (gdb_stdlog, this_frame->prev); | |
1149 | fprintf_unfiltered (gdb_stdlog, " // cached \n"); | |
1150 | } | |
1151 | return this_frame->prev; | |
1152 | } | |
1153 | this_frame->prev_p = 1; | |
55feb689 | 1154 | this_frame->stop_reason = UNWIND_NO_REASON; |
5613d8d3 | 1155 | |
5613d8d3 AC |
1156 | /* Check that this frame's ID was valid. If it wasn't, don't try to |
1157 | unwind to the prev frame. Be careful to not apply this test to | |
1158 | the sentinel frame. */ | |
756e95f1 MK |
1159 | this_id = get_frame_id (this_frame); |
1160 | if (this_frame->level >= 0 && !frame_id_p (this_id)) | |
5613d8d3 AC |
1161 | { |
1162 | if (frame_debug) | |
1163 | { | |
1164 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
1165 | fprint_frame (gdb_stdlog, NULL); | |
1166 | fprintf_unfiltered (gdb_stdlog, " // this ID is NULL }\n"); | |
1167 | } | |
55feb689 | 1168 | this_frame->stop_reason = UNWIND_NULL_ID; |
5613d8d3 AC |
1169 | return NULL; |
1170 | } | |
1171 | ||
1172 | /* Check that this frame's ID isn't inner to (younger, below, next) | |
1173 | the next frame. This happens when a frame unwind goes backwards. | |
adb54772 AC |
1174 | Exclude signal trampolines (due to sigaltstack the frame ID can |
1175 | go backwards) and sentinel frames (the test is meaningless). */ | |
1176 | if (this_frame->next->level >= 0 | |
c1bf6f65 | 1177 | && this_frame->next->unwind->type != SIGTRAMP_FRAME |
756e95f1 | 1178 | && frame_id_inner (this_id, get_frame_id (this_frame->next))) |
55feb689 DJ |
1179 | { |
1180 | if (frame_debug) | |
1181 | { | |
1182 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
1183 | fprint_frame (gdb_stdlog, NULL); | |
1184 | fprintf_unfiltered (gdb_stdlog, " // this frame ID is inner }\n"); | |
1185 | } | |
1186 | this_frame->stop_reason = UNWIND_INNER_ID; | |
1187 | return NULL; | |
1188 | } | |
5613d8d3 AC |
1189 | |
1190 | /* Check that this and the next frame are not identical. If they | |
1191 | are, there is most likely a stack cycle. As with the inner-than | |
1192 | test above, avoid comparing the inner-most and sentinel frames. */ | |
1193 | if (this_frame->level > 0 | |
756e95f1 | 1194 | && frame_id_eq (this_id, get_frame_id (this_frame->next))) |
55feb689 DJ |
1195 | { |
1196 | if (frame_debug) | |
1197 | { | |
1198 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
1199 | fprint_frame (gdb_stdlog, NULL); | |
1200 | fprintf_unfiltered (gdb_stdlog, " // this frame has same ID }\n"); | |
1201 | } | |
1202 | this_frame->stop_reason = UNWIND_SAME_ID; | |
1203 | return NULL; | |
1204 | } | |
5613d8d3 | 1205 | |
e48af409 DJ |
1206 | /* Check that this and the next frame do not unwind the PC register |
1207 | to the same memory location. If they do, then even though they | |
1208 | have different frame IDs, the new frame will be bogus; two | |
1209 | functions can't share a register save slot for the PC. This can | |
1210 | happen when the prologue analyzer finds a stack adjustment, but | |
d57df5e4 DJ |
1211 | no PC save. |
1212 | ||
1213 | This check does assume that the "PC register" is roughly a | |
1214 | traditional PC, even if the gdbarch_unwind_pc method adjusts | |
1215 | it (we do not rely on the value, only on the unwound PC being | |
1216 | dependent on this value). A potential improvement would be | |
1217 | to have the frame prev_pc method and the gdbarch unwind_pc | |
1218 | method set the same lval and location information as | |
1219 | frame_register_unwind. */ | |
e48af409 | 1220 | if (this_frame->level > 0 |
d57df5e4 | 1221 | && PC_REGNUM >= 0 |
e48af409 DJ |
1222 | && get_frame_type (this_frame) == NORMAL_FRAME |
1223 | && get_frame_type (this_frame->next) == NORMAL_FRAME) | |
1224 | { | |
1225 | int optimized, realnum; | |
1226 | enum lval_type lval, nlval; | |
1227 | CORE_ADDR addr, naddr; | |
1228 | ||
1229 | frame_register_unwind_location (this_frame, PC_REGNUM, &optimized, | |
1230 | &lval, &addr, &realnum); | |
1231 | frame_register_unwind_location (get_next_frame (this_frame), PC_REGNUM, | |
1232 | &optimized, &nlval, &naddr, &realnum); | |
1233 | ||
1234 | if (lval == lval_memory && lval == nlval && addr == naddr) | |
1235 | { | |
1236 | if (frame_debug) | |
1237 | { | |
1238 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
1239 | fprint_frame (gdb_stdlog, NULL); | |
1240 | fprintf_unfiltered (gdb_stdlog, " // no saved PC }\n"); | |
1241 | } | |
1242 | ||
1243 | this_frame->stop_reason = UNWIND_NO_SAVED_PC; | |
1244 | this_frame->prev = NULL; | |
1245 | return NULL; | |
1246 | } | |
1247 | } | |
1248 | ||
5613d8d3 AC |
1249 | /* Allocate the new frame but do not wire it in to the frame chain. |
1250 | Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along | |
1251 | frame->next to pull some fancy tricks (of course such code is, by | |
1252 | definition, recursive). Try to prevent it. | |
1253 | ||
1254 | There is no reason to worry about memory leaks, should the | |
1255 | remainder of the function fail. The allocated memory will be | |
1256 | quickly reclaimed when the frame cache is flushed, and the `we've | |
1257 | been here before' check above will stop repeated memory | |
1258 | allocation calls. */ | |
1259 | prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info); | |
1260 | prev_frame->level = this_frame->level + 1; | |
1261 | ||
1262 | /* Don't yet compute ->unwind (and hence ->type). It is computed | |
1263 | on-demand in get_frame_type, frame_register_unwind, and | |
1264 | get_frame_id. */ | |
1265 | ||
1266 | /* Don't yet compute the frame's ID. It is computed on-demand by | |
1267 | get_frame_id(). */ | |
1268 | ||
1269 | /* The unwound frame ID is validate at the start of this function, | |
1270 | as part of the logic to decide if that frame should be further | |
1271 | unwound, and not here while the prev frame is being created. | |
1272 | Doing this makes it possible for the user to examine a frame that | |
1273 | has an invalid frame ID. | |
1274 | ||
1275 | Some very old VAX code noted: [...] For the sake of argument, | |
1276 | suppose that the stack is somewhat trashed (which is one reason | |
1277 | that "info frame" exists). So, return 0 (indicating we don't | |
1278 | know the address of the arglist) if we don't know what frame this | |
1279 | frame calls. */ | |
1280 | ||
1281 | /* Link it in. */ | |
1282 | this_frame->prev = prev_frame; | |
1283 | prev_frame->next = this_frame; | |
1284 | ||
1285 | if (frame_debug) | |
1286 | { | |
1287 | fprintf_unfiltered (gdb_stdlog, "-> "); | |
1288 | fprint_frame (gdb_stdlog, prev_frame); | |
1289 | fprintf_unfiltered (gdb_stdlog, " }\n"); | |
1290 | } | |
1291 | ||
1292 | return prev_frame; | |
1293 | } | |
1294 | ||
1295 | /* Debug routine to print a NULL frame being returned. */ | |
1296 | ||
1297 | static void | |
1298 | frame_debug_got_null_frame (struct ui_file *file, | |
1299 | struct frame_info *this_frame, | |
1300 | const char *reason) | |
1301 | { | |
1302 | if (frame_debug) | |
1303 | { | |
1304 | fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame (this_frame="); | |
1305 | if (this_frame != NULL) | |
1306 | fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level); | |
1307 | else | |
1308 | fprintf_unfiltered (gdb_stdlog, "<NULL>"); | |
1309 | fprintf_unfiltered (gdb_stdlog, ") -> // %s}\n", reason); | |
1310 | } | |
1311 | } | |
1312 | ||
c8cd9f6c AC |
1313 | /* Is this (non-sentinel) frame in the "main"() function? */ |
1314 | ||
1315 | static int | |
1316 | inside_main_func (struct frame_info *this_frame) | |
1317 | { | |
1318 | struct minimal_symbol *msymbol; | |
1319 | CORE_ADDR maddr; | |
1320 | ||
1321 | if (symfile_objfile == 0) | |
1322 | return 0; | |
1323 | msymbol = lookup_minimal_symbol (main_name (), NULL, symfile_objfile); | |
1324 | if (msymbol == NULL) | |
1325 | return 0; | |
1326 | /* Make certain that the code, and not descriptor, address is | |
1327 | returned. */ | |
1328 | maddr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, | |
1329 | SYMBOL_VALUE_ADDRESS (msymbol), | |
1330 | ¤t_target); | |
1331 | return maddr == get_frame_func (this_frame); | |
1332 | } | |
1333 | ||
2315ffec RC |
1334 | /* Test whether THIS_FRAME is inside the process entry point function. */ |
1335 | ||
1336 | static int | |
1337 | inside_entry_func (struct frame_info *this_frame) | |
1338 | { | |
1339 | return (get_frame_func (this_frame) == entry_point_address ()); | |
1340 | } | |
1341 | ||
5613d8d3 AC |
1342 | /* Return a structure containing various interesting information about |
1343 | the frame that called THIS_FRAME. Returns NULL if there is entier | |
1344 | no such frame or the frame fails any of a set of target-independent | |
1345 | condition that should terminate the frame chain (e.g., as unwinding | |
1346 | past main()). | |
1347 | ||
1348 | This function should not contain target-dependent tests, such as | |
1349 | checking whether the program-counter is zero. */ | |
1350 | ||
1351 | struct frame_info * | |
1352 | get_prev_frame (struct frame_info *this_frame) | |
1353 | { | |
1354 | struct frame_info *prev_frame; | |
1355 | ||
eb4f72c5 AC |
1356 | /* Return the inner-most frame, when the caller passes in NULL. */ |
1357 | /* NOTE: cagney/2002-11-09: Not sure how this would happen. The | |
1358 | caller should have previously obtained a valid frame using | |
1359 | get_selected_frame() and then called this code - only possibility | |
1360 | I can think of is code behaving badly. | |
1361 | ||
1362 | NOTE: cagney/2003-01-10: Talk about code behaving badly. Check | |
1363 | block_innermost_frame(). It does the sequence: frame = NULL; | |
1364 | while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why | |
1365 | it couldn't be written better, I don't know. | |
1366 | ||
bbde78fa | 1367 | NOTE: cagney/2003-01-11: I suspect what is happening in |
eb4f72c5 | 1368 | block_innermost_frame() is, when the target has no state |
bbde78fa | 1369 | (registers, memory, ...), it is still calling this function. The |
eb4f72c5 AC |
1370 | assumption being that this function will return NULL indicating |
1371 | that a frame isn't possible, rather than checking that the target | |
1372 | has state and then calling get_current_frame() and | |
1373 | get_prev_frame(). This is a guess mind. */ | |
03febf99 | 1374 | if (this_frame == NULL) |
eb4f72c5 AC |
1375 | { |
1376 | /* NOTE: cagney/2002-11-09: There was a code segment here that | |
1377 | would error out when CURRENT_FRAME was NULL. The comment | |
1378 | that went with it made the claim ... | |
1379 | ||
1380 | ``This screws value_of_variable, which just wants a nice | |
1381 | clean NULL return from block_innermost_frame if there are no | |
1382 | frames. I don't think I've ever seen this message happen | |
1383 | otherwise. And returning NULL here is a perfectly legitimate | |
1384 | thing to do.'' | |
1385 | ||
1386 | Per the above, this code shouldn't even be called with a NULL | |
03febf99 | 1387 | THIS_FRAME. */ |
5613d8d3 | 1388 | frame_debug_got_null_frame (gdb_stdlog, this_frame, "this_frame NULL"); |
eb4f72c5 AC |
1389 | return current_frame; |
1390 | } | |
1391 | ||
1392 | /* There is always a frame. If this assertion fails, suspect that | |
1393 | something should be calling get_selected_frame() or | |
1394 | get_current_frame(). */ | |
03febf99 | 1395 | gdb_assert (this_frame != NULL); |
eb4f72c5 | 1396 | |
cc9bed83 RC |
1397 | /* tausq/2004-12-07: Dummy frames are skipped because it doesn't make much |
1398 | sense to stop unwinding at a dummy frame. One place where a dummy | |
1399 | frame may have an address "inside_main_func" is on HPUX. On HPUX, the | |
1400 | pcsqh register (space register for the instruction at the head of the | |
1401 | instruction queue) cannot be written directly; the only way to set it | |
1402 | is to branch to code that is in the target space. In order to implement | |
1403 | frame dummies on HPUX, the called function is made to jump back to where | |
1404 | the inferior was when the user function was called. If gdb was inside | |
1405 | the main function when we created the dummy frame, the dummy frame will | |
1406 | point inside the main function. */ | |
03febf99 | 1407 | if (this_frame->level >= 0 |
cc9bed83 | 1408 | && get_frame_type (this_frame) != DUMMY_FRAME |
25d29d70 | 1409 | && !backtrace_past_main |
c8cd9f6c AC |
1410 | && inside_main_func (this_frame)) |
1411 | /* Don't unwind past main(). Note, this is done _before_ the | |
1412 | frame has been marked as previously unwound. That way if the | |
1413 | user later decides to enable unwinds past main(), that will | |
1414 | automatically happen. */ | |
ac2bd0a9 | 1415 | { |
5613d8d3 | 1416 | frame_debug_got_null_frame (gdb_stdlog, this_frame, "inside main func"); |
ac2bd0a9 AC |
1417 | return NULL; |
1418 | } | |
eb4f72c5 | 1419 | |
4a5e53e8 DJ |
1420 | /* If the user's backtrace limit has been exceeded, stop. We must |
1421 | add two to the current level; one of those accounts for backtrace_limit | |
1422 | being 1-based and the level being 0-based, and the other accounts for | |
1423 | the level of the new frame instead of the level of the current | |
1424 | frame. */ | |
1425 | if (this_frame->level + 2 > backtrace_limit) | |
25d29d70 | 1426 | { |
4a5e53e8 DJ |
1427 | frame_debug_got_null_frame (gdb_stdlog, this_frame, |
1428 | "backtrace limit exceeded"); | |
1429 | return NULL; | |
25d29d70 AC |
1430 | } |
1431 | ||
0714963c AC |
1432 | /* If we're already inside the entry function for the main objfile, |
1433 | then it isn't valid. Don't apply this test to a dummy frame - | |
bbde78fa | 1434 | dummy frame PCs typically land in the entry func. Don't apply |
0714963c AC |
1435 | this test to the sentinel frame. Sentinel frames should always |
1436 | be allowed to unwind. */ | |
2f72f850 AC |
1437 | /* NOTE: cagney/2003-07-07: Fixed a bug in inside_main_func() - |
1438 | wasn't checking for "main" in the minimal symbols. With that | |
1439 | fixed asm-source tests now stop in "main" instead of halting the | |
bbde78fa | 1440 | backtrace in weird and wonderful ways somewhere inside the entry |
2f72f850 AC |
1441 | file. Suspect that tests for inside the entry file/func were |
1442 | added to work around that (now fixed) case. */ | |
0714963c AC |
1443 | /* NOTE: cagney/2003-07-15: danielj (if I'm reading it right) |
1444 | suggested having the inside_entry_func test use the | |
bbde78fa JM |
1445 | inside_main_func() msymbol trick (along with entry_point_address() |
1446 | I guess) to determine the address range of the start function. | |
0714963c AC |
1447 | That should provide a far better stopper than the current |
1448 | heuristics. */ | |
2315ffec RC |
1449 | /* NOTE: tausq/2004-10-09: this is needed if, for example, the compiler |
1450 | applied tail-call optimizations to main so that a function called | |
1451 | from main returns directly to the caller of main. Since we don't | |
1452 | stop at main, we should at least stop at the entry point of the | |
1453 | application. */ | |
1454 | if (!backtrace_past_entry | |
1d225535 | 1455 | && get_frame_type (this_frame) != DUMMY_FRAME && this_frame->level >= 0 |
6e4c6c91 | 1456 | && inside_entry_func (this_frame)) |
0714963c | 1457 | { |
5613d8d3 | 1458 | frame_debug_got_null_frame (gdb_stdlog, this_frame, "inside entry func"); |
0714963c AC |
1459 | return NULL; |
1460 | } | |
1461 | ||
39ee2ff0 AC |
1462 | /* Assume that the only way to get a zero PC is through something |
1463 | like a SIGSEGV or a dummy frame, and hence that NORMAL frames | |
1464 | will never unwind a zero PC. */ | |
1465 | if (this_frame->level > 0 | |
1466 | && get_frame_type (this_frame) == NORMAL_FRAME | |
1467 | && get_frame_type (get_next_frame (this_frame)) == NORMAL_FRAME | |
1468 | && get_frame_pc (this_frame) == 0) | |
1469 | { | |
1470 | frame_debug_got_null_frame (gdb_stdlog, this_frame, "zero PC"); | |
1471 | return NULL; | |
1472 | } | |
1473 | ||
5613d8d3 | 1474 | return get_prev_frame_1 (this_frame); |
eb4f72c5 AC |
1475 | } |
1476 | ||
4c1e7e9d AC |
1477 | CORE_ADDR |
1478 | get_frame_pc (struct frame_info *frame) | |
1479 | { | |
d1340264 AC |
1480 | gdb_assert (frame->next != NULL); |
1481 | return frame_pc_unwind (frame->next); | |
4c1e7e9d AC |
1482 | } |
1483 | ||
93d42b30 DJ |
1484 | /* Return an address that falls within NEXT_FRAME's caller's code |
1485 | block, assuming that the caller is a THIS_TYPE frame. */ | |
8edd5d01 AC |
1486 | |
1487 | CORE_ADDR | |
93d42b30 DJ |
1488 | frame_unwind_address_in_block (struct frame_info *next_frame, |
1489 | enum frame_type this_type) | |
8edd5d01 AC |
1490 | { |
1491 | /* A draft address. */ | |
1492 | CORE_ADDR pc = frame_pc_unwind (next_frame); | |
1493 | ||
93d42b30 DJ |
1494 | /* If NEXT_FRAME was called by a signal frame or dummy frame, then |
1495 | we shold not adjust the unwound PC. These frames may not call | |
1496 | their next frame in the normal way; the operating system or GDB | |
1497 | may have pushed their resume address manually onto the stack, so | |
1498 | it may be the very first instruction. Even if the resume address | |
1499 | was not manually pushed, they expect to be returned to. */ | |
1500 | if (this_type != NORMAL_FRAME) | |
1501 | return pc; | |
1502 | ||
8edd5d01 AC |
1503 | /* If THIS frame is not inner most (i.e., NEXT isn't the sentinel), |
1504 | and NEXT is `normal' (i.e., not a sigtramp, dummy, ....) THIS | |
1505 | frame's PC ends up pointing at the instruction fallowing the | |
1506 | "call". Adjust that PC value so that it falls on the call | |
1507 | instruction (which, hopefully, falls within THIS frame's code | |
93d42b30 | 1508 | block). So far it's proved to be a very good approximation. See |
bbde78fa | 1509 | get_frame_type() for why ->type can't be used. */ |
8edd5d01 AC |
1510 | if (next_frame->level >= 0 |
1511 | && get_frame_type (next_frame) == NORMAL_FRAME) | |
1512 | --pc; | |
1513 | return pc; | |
1514 | } | |
1515 | ||
1516 | CORE_ADDR | |
1517 | get_frame_address_in_block (struct frame_info *this_frame) | |
1518 | { | |
93d42b30 DJ |
1519 | return frame_unwind_address_in_block (this_frame->next, |
1520 | get_frame_type (this_frame)); | |
8edd5d01 AC |
1521 | } |
1522 | ||
1058bca7 AC |
1523 | static int |
1524 | pc_notcurrent (struct frame_info *frame) | |
1525 | { | |
1526 | /* If FRAME is not the innermost frame, that normally means that | |
1527 | FRAME->pc points at the return instruction (which is *after* the | |
1528 | call instruction), and we want to get the line containing the | |
1529 | call (because the call is where the user thinks the program is). | |
1530 | However, if the next frame is either a SIGTRAMP_FRAME or a | |
1531 | DUMMY_FRAME, then the next frame will contain a saved interrupt | |
1532 | PC and such a PC indicates the current (rather than next) | |
1533 | instruction/line, consequently, for such cases, want to get the | |
1534 | line containing fi->pc. */ | |
1535 | struct frame_info *next = get_next_frame (frame); | |
1536 | int notcurrent = (next != NULL && get_frame_type (next) == NORMAL_FRAME); | |
1537 | return notcurrent; | |
1538 | } | |
1539 | ||
1540 | void | |
1541 | find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal) | |
1542 | { | |
11889732 | 1543 | (*sal) = find_pc_line (get_frame_pc (frame), pc_notcurrent (frame)); |
1058bca7 AC |
1544 | } |
1545 | ||
c193f6ac AC |
1546 | /* Per "frame.h", return the ``address'' of the frame. Code should |
1547 | really be using get_frame_id(). */ | |
1548 | CORE_ADDR | |
1549 | get_frame_base (struct frame_info *fi) | |
1550 | { | |
d0a55772 | 1551 | return get_frame_id (fi).stack_addr; |
c193f6ac AC |
1552 | } |
1553 | ||
da62e633 AC |
1554 | /* High-level offsets into the frame. Used by the debug info. */ |
1555 | ||
1556 | CORE_ADDR | |
1557 | get_frame_base_address (struct frame_info *fi) | |
1558 | { | |
7df05f2b | 1559 | if (get_frame_type (fi) != NORMAL_FRAME) |
da62e633 AC |
1560 | return 0; |
1561 | if (fi->base == NULL) | |
e8a89fe2 | 1562 | fi->base = frame_base_find_by_frame (fi->next); |
da62e633 AC |
1563 | /* Sneaky: If the low-level unwind and high-level base code share a |
1564 | common unwinder, let them share the prologue cache. */ | |
1565 | if (fi->base->unwind == fi->unwind) | |
1566 | return fi->base->this_base (fi->next, &fi->prologue_cache); | |
1567 | return fi->base->this_base (fi->next, &fi->base_cache); | |
1568 | } | |
1569 | ||
1570 | CORE_ADDR | |
1571 | get_frame_locals_address (struct frame_info *fi) | |
1572 | { | |
1573 | void **cache; | |
7df05f2b | 1574 | if (get_frame_type (fi) != NORMAL_FRAME) |
da62e633 AC |
1575 | return 0; |
1576 | /* If there isn't a frame address method, find it. */ | |
1577 | if (fi->base == NULL) | |
e8a89fe2 | 1578 | fi->base = frame_base_find_by_frame (fi->next); |
da62e633 AC |
1579 | /* Sneaky: If the low-level unwind and high-level base code share a |
1580 | common unwinder, let them share the prologue cache. */ | |
1581 | if (fi->base->unwind == fi->unwind) | |
1582 | cache = &fi->prologue_cache; | |
1583 | else | |
1584 | cache = &fi->base_cache; | |
1585 | return fi->base->this_locals (fi->next, cache); | |
1586 | } | |
1587 | ||
1588 | CORE_ADDR | |
1589 | get_frame_args_address (struct frame_info *fi) | |
1590 | { | |
1591 | void **cache; | |
7df05f2b | 1592 | if (get_frame_type (fi) != NORMAL_FRAME) |
da62e633 AC |
1593 | return 0; |
1594 | /* If there isn't a frame address method, find it. */ | |
1595 | if (fi->base == NULL) | |
e8a89fe2 | 1596 | fi->base = frame_base_find_by_frame (fi->next); |
da62e633 AC |
1597 | /* Sneaky: If the low-level unwind and high-level base code share a |
1598 | common unwinder, let them share the prologue cache. */ | |
1599 | if (fi->base->unwind == fi->unwind) | |
1600 | cache = &fi->prologue_cache; | |
1601 | else | |
1602 | cache = &fi->base_cache; | |
1603 | return fi->base->this_args (fi->next, cache); | |
1604 | } | |
1605 | ||
85cf597a AC |
1606 | /* Level of the selected frame: 0 for innermost, 1 for its caller, ... |
1607 | or -1 for a NULL frame. */ | |
1608 | ||
1609 | int | |
1610 | frame_relative_level (struct frame_info *fi) | |
1611 | { | |
1612 | if (fi == NULL) | |
1613 | return -1; | |
1614 | else | |
1615 | return fi->level; | |
1616 | } | |
1617 | ||
5a203e44 AC |
1618 | enum frame_type |
1619 | get_frame_type (struct frame_info *frame) | |
1620 | { | |
c1bf6f65 AC |
1621 | if (frame->unwind == NULL) |
1622 | /* Initialize the frame's unwinder because that's what | |
1623 | provides the frame's type. */ | |
1624 | frame->unwind = frame_unwind_find_by_frame (frame->next, | |
1625 | &frame->prologue_cache); | |
1626 | return frame->unwind->type; | |
5a203e44 AC |
1627 | } |
1628 | ||
b87efeee | 1629 | void |
2f107107 | 1630 | deprecated_update_frame_pc_hack (struct frame_info *frame, CORE_ADDR pc) |
b87efeee | 1631 | { |
7f78e237 AC |
1632 | if (frame_debug) |
1633 | fprintf_unfiltered (gdb_stdlog, | |
1634 | "{ deprecated_update_frame_pc_hack (frame=%d,pc=0x%s) }\n", | |
1635 | frame->level, paddr_nz (pc)); | |
e0d2ae16 | 1636 | /* NOTE: cagney/2003-03-11: Some architectures (e.g., Arm) are |
bbde78fa | 1637 | maintaining a locally allocated frame object. Since such frames |
e0d2ae16 AC |
1638 | are not in the frame chain, it isn't possible to assume that the |
1639 | frame has a next. Sigh. */ | |
1640 | if (frame->next != NULL) | |
1641 | { | |
1642 | /* While we're at it, update this frame's cached PC value, found | |
1643 | in the next frame. Oh for the day when "struct frame_info" | |
1644 | is opaque and this hack on hack can just go away. */ | |
d1340264 AC |
1645 | frame->next->prev_pc.value = pc; |
1646 | frame->next->prev_pc.p = 1; | |
e0d2ae16 | 1647 | } |
2f107107 AC |
1648 | } |
1649 | ||
1650 | void | |
1651 | deprecated_update_frame_base_hack (struct frame_info *frame, CORE_ADDR base) | |
1652 | { | |
7f78e237 AC |
1653 | if (frame_debug) |
1654 | fprintf_unfiltered (gdb_stdlog, | |
1655 | "{ deprecated_update_frame_base_hack (frame=%d,base=0x%s) }\n", | |
1656 | frame->level, paddr_nz (base)); | |
2f107107 | 1657 | /* See comment in "frame.h". */ |
d0a55772 | 1658 | frame->this_id.value.stack_addr = base; |
b87efeee AC |
1659 | } |
1660 | ||
ae1e7417 AC |
1661 | /* Memory access methods. */ |
1662 | ||
1663 | void | |
10c42a71 AC |
1664 | get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr, |
1665 | gdb_byte *buf, int len) | |
ae1e7417 AC |
1666 | { |
1667 | read_memory (addr, buf, len); | |
1668 | } | |
1669 | ||
1670 | LONGEST | |
1671 | get_frame_memory_signed (struct frame_info *this_frame, CORE_ADDR addr, | |
1672 | int len) | |
1673 | { | |
1674 | return read_memory_integer (addr, len); | |
1675 | } | |
1676 | ||
1677 | ULONGEST | |
1678 | get_frame_memory_unsigned (struct frame_info *this_frame, CORE_ADDR addr, | |
1679 | int len) | |
1680 | { | |
1681 | return read_memory_unsigned_integer (addr, len); | |
1682 | } | |
1683 | ||
304396fb AC |
1684 | int |
1685 | safe_frame_unwind_memory (struct frame_info *this_frame, | |
10c42a71 | 1686 | CORE_ADDR addr, gdb_byte *buf, int len) |
304396fb | 1687 | { |
359a9262 JB |
1688 | /* NOTE: read_memory_nobpt returns zero on success! */ |
1689 | return !read_memory_nobpt (addr, buf, len); | |
304396fb AC |
1690 | } |
1691 | ||
ae1e7417 AC |
1692 | /* Architecture method. */ |
1693 | ||
1694 | struct gdbarch * | |
1695 | get_frame_arch (struct frame_info *this_frame) | |
1696 | { | |
1697 | return current_gdbarch; | |
1698 | } | |
1699 | ||
a9e5fdc2 AC |
1700 | /* Stack pointer methods. */ |
1701 | ||
1702 | CORE_ADDR | |
1703 | get_frame_sp (struct frame_info *this_frame) | |
1704 | { | |
1705 | return frame_sp_unwind (this_frame->next); | |
1706 | } | |
1707 | ||
1708 | CORE_ADDR | |
1709 | frame_sp_unwind (struct frame_info *next_frame) | |
1710 | { | |
bbde78fa | 1711 | /* Normality - an architecture that provides a way of obtaining any |
a9e5fdc2 AC |
1712 | frame inner-most address. */ |
1713 | if (gdbarch_unwind_sp_p (current_gdbarch)) | |
1714 | return gdbarch_unwind_sp (current_gdbarch, next_frame); | |
a9e5fdc2 AC |
1715 | /* Now things are really are grim. Hope that the value returned by |
1716 | the SP_REGNUM register is meaningful. */ | |
1717 | if (SP_REGNUM >= 0) | |
1718 | { | |
1719 | ULONGEST sp; | |
1720 | frame_unwind_unsigned_register (next_frame, SP_REGNUM, &sp); | |
1721 | return sp; | |
1722 | } | |
e2e0b3e5 | 1723 | internal_error (__FILE__, __LINE__, _("Missing unwind SP method")); |
a9e5fdc2 AC |
1724 | } |
1725 | ||
55feb689 DJ |
1726 | /* Return the reason why we can't unwind past FRAME. */ |
1727 | ||
1728 | enum unwind_stop_reason | |
1729 | get_frame_unwind_stop_reason (struct frame_info *frame) | |
1730 | { | |
1731 | /* If we haven't tried to unwind past this point yet, then assume | |
1732 | that unwinding would succeed. */ | |
1733 | if (frame->prev_p == 0) | |
1734 | return UNWIND_NO_REASON; | |
1735 | ||
1736 | /* Otherwise, we set a reason when we succeeded (or failed) to | |
1737 | unwind. */ | |
1738 | return frame->stop_reason; | |
1739 | } | |
1740 | ||
1741 | /* Return a string explaining REASON. */ | |
1742 | ||
1743 | const char * | |
1744 | frame_stop_reason_string (enum unwind_stop_reason reason) | |
1745 | { | |
1746 | switch (reason) | |
1747 | { | |
1748 | case UNWIND_NULL_ID: | |
1749 | return _("unwinder did not report frame ID"); | |
1750 | ||
1751 | case UNWIND_INNER_ID: | |
1752 | return _("previous frame inner to this frame (corrupt stack?)"); | |
1753 | ||
1754 | case UNWIND_SAME_ID: | |
1755 | return _("previous frame identical to this frame (corrupt stack?)"); | |
1756 | ||
e48af409 DJ |
1757 | case UNWIND_NO_SAVED_PC: |
1758 | return _("frame did not save the PC"); | |
1759 | ||
55feb689 DJ |
1760 | case UNWIND_NO_REASON: |
1761 | case UNWIND_FIRST_ERROR: | |
1762 | default: | |
1763 | internal_error (__FILE__, __LINE__, | |
1764 | "Invalid frame stop reason"); | |
1765 | } | |
1766 | } | |
1767 | ||
b9362cc7 AC |
1768 | extern initialize_file_ftype _initialize_frame; /* -Wmissing-prototypes */ |
1769 | ||
25d29d70 AC |
1770 | static struct cmd_list_element *set_backtrace_cmdlist; |
1771 | static struct cmd_list_element *show_backtrace_cmdlist; | |
1772 | ||
1773 | static void | |
1774 | set_backtrace_cmd (char *args, int from_tty) | |
1775 | { | |
1776 | help_list (set_backtrace_cmdlist, "set backtrace ", -1, gdb_stdout); | |
1777 | } | |
1778 | ||
1779 | static void | |
1780 | show_backtrace_cmd (char *args, int from_tty) | |
1781 | { | |
1782 | cmd_show_list (show_backtrace_cmdlist, from_tty, ""); | |
1783 | } | |
1784 | ||
4c1e7e9d AC |
1785 | void |
1786 | _initialize_frame (void) | |
1787 | { | |
1788 | obstack_init (&frame_cache_obstack); | |
eb4f72c5 | 1789 | |
f4c5303c OF |
1790 | observer_attach_target_changed (frame_observer_target_changed); |
1791 | ||
1bedd215 | 1792 | add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, _("\ |
25d29d70 | 1793 | Set backtrace specific variables.\n\ |
1bedd215 | 1794 | Configure backtrace variables such as the backtrace limit"), |
25d29d70 AC |
1795 | &set_backtrace_cmdlist, "set backtrace ", |
1796 | 0/*allow-unknown*/, &setlist); | |
1bedd215 | 1797 | add_prefix_cmd ("backtrace", class_maintenance, show_backtrace_cmd, _("\ |
25d29d70 | 1798 | Show backtrace specific variables\n\ |
1bedd215 | 1799 | Show backtrace variables such as the backtrace limit"), |
25d29d70 AC |
1800 | &show_backtrace_cmdlist, "show backtrace ", |
1801 | 0/*allow-unknown*/, &showlist); | |
1802 | ||
1803 | add_setshow_boolean_cmd ("past-main", class_obscure, | |
7915a72c AC |
1804 | &backtrace_past_main, _("\ |
1805 | Set whether backtraces should continue past \"main\"."), _("\ | |
1806 | Show whether backtraces should continue past \"main\"."), _("\ | |
eb4f72c5 AC |
1807 | Normally the caller of \"main\" is not of interest, so GDB will terminate\n\ |
1808 | the backtrace at \"main\". Set this variable if you need to see the rest\n\ | |
7915a72c | 1809 | of the stack trace."), |
2c5b56ce | 1810 | NULL, |
920d2a44 | 1811 | show_backtrace_past_main, |
2c5b56ce | 1812 | &set_backtrace_cmdlist, |
25d29d70 AC |
1813 | &show_backtrace_cmdlist); |
1814 | ||
2315ffec | 1815 | add_setshow_boolean_cmd ("past-entry", class_obscure, |
7915a72c AC |
1816 | &backtrace_past_entry, _("\ |
1817 | Set whether backtraces should continue past the entry point of a program."), | |
1818 | _("\ | |
1819 | Show whether backtraces should continue past the entry point of a program."), | |
1820 | _("\ | |
2315ffec RC |
1821 | Normally there are no callers beyond the entry point of a program, so GDB\n\ |
1822 | will terminate the backtrace there. Set this variable if you need to see \n\ | |
7915a72c | 1823 | the rest of the stack trace."), |
2c5b56ce | 1824 | NULL, |
920d2a44 | 1825 | show_backtrace_past_entry, |
2c5b56ce | 1826 | &set_backtrace_cmdlist, |
2315ffec RC |
1827 | &show_backtrace_cmdlist); |
1828 | ||
4a5e53e8 DJ |
1829 | add_setshow_integer_cmd ("limit", class_obscure, |
1830 | &backtrace_limit, _("\ | |
7915a72c AC |
1831 | Set an upper bound on the number of backtrace levels."), _("\ |
1832 | Show the upper bound on the number of backtrace levels."), _("\ | |
fec74868 | 1833 | No more than the specified number of frames can be displayed or examined.\n\ |
7915a72c | 1834 | Zero is unlimited."), |
4a5e53e8 DJ |
1835 | NULL, |
1836 | show_backtrace_limit, | |
1837 | &set_backtrace_cmdlist, | |
1838 | &show_backtrace_cmdlist); | |
ac2bd0a9 AC |
1839 | |
1840 | /* Debug this files internals. */ | |
85c07804 AC |
1841 | add_setshow_zinteger_cmd ("frame", class_maintenance, &frame_debug, _("\ |
1842 | Set frame debugging."), _("\ | |
1843 | Show frame debugging."), _("\ | |
1844 | When non-zero, frame specific internal debugging is enabled."), | |
1845 | NULL, | |
920d2a44 | 1846 | show_frame_debug, |
85c07804 | 1847 | &setdebuglist, &showdebuglist); |
4c1e7e9d | 1848 | } |