Commit | Line | Data |
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4f460812 | 1 | /* Cache and manage frames for GDB, the GNU debugger. |
96cb11df AC |
2 | |
3 | Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, | |
51603483 | 4 | 2001, 2002, 2003 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 | |
20 | Foundation, Inc., 59 Temple Place - Suite 330, | |
21 | Boston, MA 02111-1307, USA. */ | |
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 AC |
30 | #include "gdb_string.h" |
31 | #include "builtin-regs.h" | |
4c1e7e9d AC |
32 | #include "gdb_obstack.h" |
33 | #include "dummy-frame.h" | |
34 | #include "gdbcore.h" | |
35 | #include "annotate.h" | |
6e7f8b9c | 36 | #include "language.h" |
494cca16 | 37 | #include "frame-unwind.h" |
eb4f72c5 AC |
38 | #include "command.h" |
39 | #include "gdbcmd.h" | |
40 | ||
41 | /* Flag to indicate whether backtraces should stop at main. */ | |
42 | ||
43 | static int backtrace_below_main; | |
d65fe839 | 44 | |
7a424e99 | 45 | /* Return a frame uniq ID that can be used to, later, re-find the |
101dcfbe AC |
46 | frame. */ |
47 | ||
7a424e99 AC |
48 | struct frame_id |
49 | get_frame_id (struct frame_info *fi) | |
101dcfbe AC |
50 | { |
51 | if (fi == NULL) | |
52 | { | |
7a424e99 | 53 | return null_frame_id; |
101dcfbe AC |
54 | } |
55 | else | |
56 | { | |
7a424e99 AC |
57 | struct frame_id id; |
58 | id.base = fi->frame; | |
59 | id.pc = fi->pc; | |
60 | return id; | |
101dcfbe AC |
61 | } |
62 | } | |
63 | ||
7a424e99 AC |
64 | const struct frame_id null_frame_id; /* All zeros. */ |
65 | ||
66 | struct frame_id | |
67 | frame_id_build (CORE_ADDR base, CORE_ADDR func_or_pc) | |
68 | { | |
69 | struct frame_id id; | |
70 | id.base = base; | |
71 | id.pc = func_or_pc; | |
72 | return id; | |
73 | } | |
74 | ||
75 | int | |
76 | frame_id_p (struct frame_id l) | |
77 | { | |
78 | /* The .func can be NULL but the .base cannot. */ | |
79 | return (l.base != 0); | |
80 | } | |
81 | ||
82 | int | |
83 | frame_id_eq (struct frame_id l, struct frame_id r) | |
84 | { | |
85 | /* If .base is different, the frames are different. */ | |
86 | if (l.base != r.base) | |
87 | return 0; | |
88 | /* Add a test to check that the frame ID's are for the same function | |
89 | here. */ | |
90 | return 1; | |
91 | } | |
92 | ||
93 | int | |
94 | frame_id_inner (struct frame_id l, struct frame_id r) | |
95 | { | |
96 | /* Only return non-zero when strictly inner than. Note that, per | |
97 | comment in "frame.h", there is some fuzz here. Frameless | |
98 | functions are not strictly inner than (same .base but different | |
99 | .func). */ | |
100 | return INNER_THAN (l.base, r.base); | |
101 | } | |
102 | ||
101dcfbe AC |
103 | struct frame_info * |
104 | frame_find_by_id (struct frame_id id) | |
105 | { | |
106 | struct frame_info *frame; | |
107 | ||
108 | /* ZERO denotes the null frame, let the caller decide what to do | |
109 | about it. Should it instead return get_current_frame()? */ | |
7a424e99 | 110 | if (!frame_id_p (id)) |
101dcfbe AC |
111 | return NULL; |
112 | ||
113 | for (frame = get_current_frame (); | |
114 | frame != NULL; | |
115 | frame = get_prev_frame (frame)) | |
116 | { | |
7a424e99 AC |
117 | struct frame_id this = get_frame_id (frame); |
118 | if (frame_id_eq (id, this)) | |
119 | /* An exact match. */ | |
120 | return frame; | |
121 | if (frame_id_inner (id, this)) | |
122 | /* Gone to far. */ | |
101dcfbe | 123 | return NULL; |
7a424e99 AC |
124 | /* Either, we're not yet gone far enough out along the frame |
125 | chain (inner(this,id), or we're comparing frameless functions | |
126 | (same .base, different .func, no test available). Struggle | |
127 | on until we've definitly gone to far. */ | |
101dcfbe AC |
128 | } |
129 | return NULL; | |
130 | } | |
131 | ||
f18c5a73 AC |
132 | CORE_ADDR |
133 | frame_pc_unwind (struct frame_info *frame) | |
134 | { | |
135 | if (!frame->pc_unwind_cache_p) | |
136 | { | |
494cca16 | 137 | frame->pc_unwind_cache = frame->unwind->pc (frame, &frame->unwind_cache); |
f18c5a73 AC |
138 | frame->pc_unwind_cache_p = 1; |
139 | } | |
140 | return frame->pc_unwind_cache; | |
141 | } | |
142 | ||
c689142b AC |
143 | struct frame_id |
144 | frame_id_unwind (struct frame_info *frame) | |
145 | { | |
146 | if (!frame->id_unwind_cache_p) | |
147 | { | |
494cca16 | 148 | frame->unwind->id (frame, &frame->unwind_cache, &frame->id_unwind_cache); |
c689142b AC |
149 | frame->id_unwind_cache_p = 1; |
150 | } | |
151 | return frame->id_unwind_cache; | |
152 | } | |
153 | ||
dbe9fe58 AC |
154 | void |
155 | frame_pop (struct frame_info *frame) | |
156 | { | |
157 | /* FIXME: cagney/2003-01-18: There is probably a chicken-egg problem | |
158 | with passing in current_regcache. The pop function needs to be | |
159 | written carefully so as to not overwrite registers whose [old] | |
160 | values are needed to restore other registers. Instead, this code | |
161 | should pass in a scratch cache and, as a second step, restore the | |
162 | registers using that. */ | |
163 | frame->unwind->pop (frame, &frame->unwind_cache, current_regcache); | |
164 | flush_cached_frames (); | |
165 | } | |
c689142b | 166 | |
4f460812 AC |
167 | void |
168 | frame_register_unwind (struct frame_info *frame, int regnum, | |
169 | int *optimizedp, enum lval_type *lvalp, | |
170 | CORE_ADDR *addrp, int *realnump, void *bufferp) | |
171 | { | |
172 | struct frame_unwind_cache *cache; | |
173 | ||
174 | /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates | |
175 | that the value proper does not need to be fetched. */ | |
176 | gdb_assert (optimizedp != NULL); | |
177 | gdb_assert (lvalp != NULL); | |
178 | gdb_assert (addrp != NULL); | |
179 | gdb_assert (realnump != NULL); | |
180 | /* gdb_assert (bufferp != NULL); */ | |
181 | ||
182 | /* NOTE: cagney/2002-04-14: It would be nice if, instead of a | |
183 | special case, there was always an inner frame dedicated to the | |
184 | hardware registers. Unfortunatly, there is too much unwind code | |
185 | around that looks up/down the frame chain while making the | |
186 | assumption that each frame level is using the same unwind code. */ | |
187 | ||
188 | if (frame == NULL) | |
189 | { | |
190 | /* We're in the inner-most frame, get the value direct from the | |
191 | register cache. */ | |
192 | *optimizedp = 0; | |
193 | *lvalp = lval_register; | |
fa5f27c7 AC |
194 | /* ULGH! Code uses the offset into the raw register byte array |
195 | as a way of identifying a register. */ | |
196 | *addrp = REGISTER_BYTE (regnum); | |
4f460812 AC |
197 | /* Should this code test ``register_cached (regnum) < 0'' and do |
198 | something like set realnum to -1 when the register isn't | |
199 | available? */ | |
200 | *realnump = regnum; | |
201 | if (bufferp) | |
4caf0990 | 202 | deprecated_read_register_gen (regnum, bufferp); |
4f460812 AC |
203 | return; |
204 | } | |
205 | ||
206 | /* Ask this frame to unwind its register. */ | |
494cca16 AC |
207 | frame->unwind->reg (frame, &frame->unwind_cache, regnum, |
208 | optimizedp, lvalp, addrp, realnump, bufferp); | |
4f460812 AC |
209 | } |
210 | ||
a216a322 AC |
211 | void |
212 | frame_register (struct frame_info *frame, int regnum, | |
213 | int *optimizedp, enum lval_type *lvalp, | |
214 | CORE_ADDR *addrp, int *realnump, void *bufferp) | |
215 | { | |
216 | /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates | |
217 | that the value proper does not need to be fetched. */ | |
218 | gdb_assert (optimizedp != NULL); | |
219 | gdb_assert (lvalp != NULL); | |
220 | gdb_assert (addrp != NULL); | |
221 | gdb_assert (realnump != NULL); | |
222 | /* gdb_assert (bufferp != NULL); */ | |
223 | ||
224 | /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset | |
225 | of the register in the register cache. It should instead return | |
226 | the REGNUM corresponding to that register. Translate the . */ | |
227 | if (GET_SAVED_REGISTER_P ()) | |
228 | { | |
229 | GET_SAVED_REGISTER (bufferp, optimizedp, addrp, frame, regnum, lvalp); | |
230 | /* Compute the REALNUM if the caller wants it. */ | |
231 | if (*lvalp == lval_register) | |
232 | { | |
233 | int regnum; | |
234 | for (regnum = 0; regnum < NUM_REGS + NUM_PSEUDO_REGS; regnum++) | |
235 | { | |
236 | if (*addrp == register_offset_hack (current_gdbarch, regnum)) | |
237 | { | |
238 | *realnump = regnum; | |
239 | return; | |
240 | } | |
241 | } | |
242 | internal_error (__FILE__, __LINE__, | |
243 | "Failed to compute the register number corresponding" | |
244 | " to 0x%s", paddr_d (*addrp)); | |
245 | } | |
246 | *realnump = -1; | |
247 | return; | |
248 | } | |
249 | ||
250 | /* Reached the the bottom (youngest, inner most) of the frame chain | |
251 | (youngest, inner most) frame, go direct to the hardware register | |
252 | cache (do not pass go, do not try to cache the value, ...). The | |
253 | unwound value would have been cached in frame->next but that | |
254 | doesn't exist. This doesn't matter as the hardware register | |
255 | cache is stopping any unnecessary accesses to the target. */ | |
256 | ||
257 | /* NOTE: cagney/2002-04-14: It would be nice if, instead of a | |
258 | special case, there was always an inner frame dedicated to the | |
259 | hardware registers. Unfortunatly, there is too much unwind code | |
260 | around that looks up/down the frame chain while making the | |
261 | assumption that each frame level is using the same unwind code. */ | |
262 | ||
263 | if (frame == NULL) | |
264 | frame_register_unwind (NULL, regnum, optimizedp, lvalp, addrp, realnump, | |
265 | bufferp); | |
266 | else | |
267 | frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp, | |
268 | realnump, bufferp); | |
269 | } | |
270 | ||
135c175f AC |
271 | void |
272 | frame_unwind_signed_register (struct frame_info *frame, int regnum, | |
273 | LONGEST *val) | |
274 | { | |
275 | int optimized; | |
276 | CORE_ADDR addr; | |
277 | int realnum; | |
278 | enum lval_type lval; | |
279 | void *buf = alloca (MAX_REGISTER_RAW_SIZE); | |
280 | frame_register_unwind (frame, regnum, &optimized, &lval, &addr, | |
281 | &realnum, buf); | |
282 | (*val) = extract_signed_integer (buf, REGISTER_VIRTUAL_SIZE (regnum)); | |
283 | } | |
284 | ||
285 | void | |
286 | frame_unwind_unsigned_register (struct frame_info *frame, int regnum, | |
287 | ULONGEST *val) | |
288 | { | |
289 | int optimized; | |
290 | CORE_ADDR addr; | |
291 | int realnum; | |
292 | enum lval_type lval; | |
293 | void *buf = alloca (MAX_REGISTER_RAW_SIZE); | |
294 | frame_register_unwind (frame, regnum, &optimized, &lval, &addr, | |
295 | &realnum, buf); | |
296 | (*val) = extract_unsigned_integer (buf, REGISTER_VIRTUAL_SIZE (regnum)); | |
297 | } | |
4f460812 | 298 | |
f908a0eb AC |
299 | void |
300 | frame_read_unsigned_register (struct frame_info *frame, int regnum, | |
301 | ULONGEST *val) | |
302 | { | |
303 | /* NOTE: cagney/2002-10-31: There is a bit of dogma here - there is | |
304 | always a frame. Both this, and the equivalent | |
305 | frame_read_signed_register() function, can only be called with a | |
306 | valid frame. If, for some reason, this function is called | |
307 | without a frame then the problem isn't here, but rather in the | |
308 | caller. It should of first created a frame and then passed that | |
309 | in. */ | |
310 | /* NOTE: cagney/2002-10-31: As a side bar, keep in mind that the | |
311 | ``current_frame'' should not be treated as a special case. While | |
312 | ``get_next_frame (current_frame) == NULL'' currently holds, it | |
313 | should, as far as possible, not be relied upon. In the future, | |
314 | ``get_next_frame (current_frame)'' may instead simply return a | |
315 | normal frame object that simply always gets register values from | |
316 | the register cache. Consequently, frame code should try to avoid | |
317 | tests like ``if get_next_frame() == NULL'' and instead just rely | |
318 | on recursive frame calls (like the below code) when manipulating | |
319 | a frame chain. */ | |
320 | gdb_assert (frame != NULL); | |
321 | frame_unwind_unsigned_register (get_next_frame (frame), regnum, val); | |
322 | } | |
323 | ||
324 | void | |
325 | frame_read_signed_register (struct frame_info *frame, int regnum, | |
326 | LONGEST *val) | |
327 | { | |
328 | /* See note in frame_read_unsigned_register(). */ | |
329 | gdb_assert (frame != NULL); | |
330 | frame_unwind_signed_register (get_next_frame (frame), regnum, val); | |
331 | } | |
332 | ||
18cde8d5 | 333 | static void |
4f460812 AC |
334 | generic_unwind_get_saved_register (char *raw_buffer, |
335 | int *optimizedp, | |
336 | CORE_ADDR *addrp, | |
337 | struct frame_info *frame, | |
338 | int regnum, | |
339 | enum lval_type *lvalp) | |
340 | { | |
341 | int optimizedx; | |
342 | CORE_ADDR addrx; | |
343 | int realnumx; | |
344 | enum lval_type lvalx; | |
345 | ||
346 | if (!target_has_registers) | |
347 | error ("No registers."); | |
348 | ||
349 | /* Keep things simple, ensure that all the pointers (except valuep) | |
350 | are non NULL. */ | |
351 | if (optimizedp == NULL) | |
352 | optimizedp = &optimizedx; | |
353 | if (lvalp == NULL) | |
354 | lvalp = &lvalx; | |
355 | if (addrp == NULL) | |
356 | addrp = &addrx; | |
357 | ||
358 | /* Reached the the bottom (youngest, inner most) of the frame chain | |
359 | (youngest, inner most) frame, go direct to the hardware register | |
360 | cache (do not pass go, do not try to cache the value, ...). The | |
361 | unwound value would have been cached in frame->next but that | |
362 | doesn't exist. This doesn't matter as the hardware register | |
363 | cache is stopping any unnecessary accesses to the target. */ | |
364 | ||
365 | /* NOTE: cagney/2002-04-14: It would be nice if, instead of a | |
366 | special case, there was always an inner frame dedicated to the | |
367 | hardware registers. Unfortunatly, there is too much unwind code | |
368 | around that looks up/down the frame chain while making the | |
369 | assumption that each frame level is using the same unwind code. */ | |
370 | ||
371 | if (frame == NULL) | |
372 | frame_register_unwind (NULL, regnum, optimizedp, lvalp, addrp, &realnumx, | |
373 | raw_buffer); | |
374 | else | |
375 | frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp, | |
376 | &realnumx, raw_buffer); | |
377 | } | |
378 | ||
d65fe839 AC |
379 | void |
380 | get_saved_register (char *raw_buffer, | |
381 | int *optimized, | |
382 | CORE_ADDR *addrp, | |
383 | struct frame_info *frame, | |
384 | int regnum, | |
385 | enum lval_type *lval) | |
386 | { | |
a216a322 AC |
387 | if (GET_SAVED_REGISTER_P ()) |
388 | { | |
389 | GET_SAVED_REGISTER (raw_buffer, optimized, addrp, frame, regnum, lval); | |
390 | return; | |
391 | } | |
392 | generic_unwind_get_saved_register (raw_buffer, optimized, addrp, frame, | |
393 | regnum, lval); | |
d65fe839 AC |
394 | } |
395 | ||
cda5a58a | 396 | /* frame_register_read () |
d65fe839 | 397 | |
cda5a58a | 398 | Find and return the value of REGNUM for the specified stack frame. |
d65fe839 AC |
399 | The number of bytes copied is REGISTER_RAW_SIZE (REGNUM). |
400 | ||
cda5a58a | 401 | Returns 0 if the register value could not be found. */ |
d65fe839 | 402 | |
cda5a58a AC |
403 | int |
404 | frame_register_read (struct frame_info *frame, int regnum, void *myaddr) | |
d65fe839 | 405 | { |
a216a322 AC |
406 | int optimized; |
407 | enum lval_type lval; | |
408 | CORE_ADDR addr; | |
409 | int realnum; | |
410 | frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr); | |
d65fe839 | 411 | |
c97dcfc7 AC |
412 | /* FIXME: cagney/2002-05-15: This test, is just bogus. |
413 | ||
414 | It indicates that the target failed to supply a value for a | |
415 | register because it was "not available" at this time. Problem | |
416 | is, the target still has the register and so get saved_register() | |
417 | may be returning a value saved on the stack. */ | |
418 | ||
d65fe839 | 419 | if (register_cached (regnum) < 0) |
cda5a58a | 420 | return 0; /* register value not available */ |
d65fe839 | 421 | |
a216a322 | 422 | return !optimized; |
d65fe839 | 423 | } |
e36180d7 AC |
424 | |
425 | ||
426 | /* Map between a frame register number and its name. A frame register | |
427 | space is a superset of the cooked register space --- it also | |
428 | includes builtin registers. */ | |
429 | ||
430 | int | |
431 | frame_map_name_to_regnum (const char *name, int len) | |
432 | { | |
433 | int i; | |
434 | ||
435 | /* Search register name space. */ | |
436 | for (i = 0; i < NUM_REGS + NUM_PSEUDO_REGS; i++) | |
437 | if (REGISTER_NAME (i) && len == strlen (REGISTER_NAME (i)) | |
438 | && strncmp (name, REGISTER_NAME (i), len) == 0) | |
439 | { | |
440 | return i; | |
441 | } | |
442 | ||
443 | /* Try builtin registers. */ | |
444 | i = builtin_reg_map_name_to_regnum (name, len); | |
445 | if (i >= 0) | |
446 | { | |
447 | /* A builtin register doesn't fall into the architecture's | |
448 | register range. */ | |
449 | gdb_assert (i >= NUM_REGS + NUM_PSEUDO_REGS); | |
450 | return i; | |
451 | } | |
452 | ||
453 | return -1; | |
454 | } | |
455 | ||
456 | const char * | |
457 | frame_map_regnum_to_name (int regnum) | |
458 | { | |
459 | if (regnum < 0) | |
460 | return NULL; | |
461 | if (regnum < NUM_REGS + NUM_PSEUDO_REGS) | |
462 | return REGISTER_NAME (regnum); | |
463 | return builtin_reg_map_regnum_to_name (regnum); | |
464 | } | |
4c1e7e9d AC |
465 | |
466 | /* Info about the innermost stack frame (contents of FP register) */ | |
467 | ||
468 | static struct frame_info *current_frame; | |
469 | ||
470 | /* Cache for frame addresses already read by gdb. Valid only while | |
471 | inferior is stopped. Control variables for the frame cache should | |
472 | be local to this module. */ | |
473 | ||
474 | static struct obstack frame_cache_obstack; | |
475 | ||
476 | void * | |
479ab5a0 | 477 | frame_obstack_zalloc (unsigned long size) |
4c1e7e9d | 478 | { |
479ab5a0 AC |
479 | void *data = obstack_alloc (&frame_cache_obstack, size); |
480 | memset (data, 0, size); | |
481 | return data; | |
4c1e7e9d AC |
482 | } |
483 | ||
6baff1d2 | 484 | CORE_ADDR * |
4c1e7e9d AC |
485 | frame_saved_regs_zalloc (struct frame_info *fi) |
486 | { | |
487 | fi->saved_regs = (CORE_ADDR *) | |
479ab5a0 | 488 | frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS); |
6baff1d2 | 489 | return fi->saved_regs; |
4c1e7e9d AC |
490 | } |
491 | ||
6baff1d2 AC |
492 | CORE_ADDR * |
493 | get_frame_saved_regs (struct frame_info *fi) | |
494 | { | |
495 | return fi->saved_regs; | |
496 | } | |
4c1e7e9d AC |
497 | |
498 | /* Return the innermost (currently executing) stack frame. */ | |
499 | ||
500 | struct frame_info * | |
501 | get_current_frame (void) | |
502 | { | |
503 | if (current_frame == NULL) | |
504 | { | |
505 | if (target_has_stack) | |
506 | current_frame = create_new_frame (read_fp (), read_pc ()); | |
507 | else | |
508 | error ("No stack."); | |
509 | } | |
510 | return current_frame; | |
511 | } | |
512 | ||
6e7f8b9c AC |
513 | /* The "selected" stack frame is used by default for local and arg |
514 | access. May be zero, for no selected frame. */ | |
515 | ||
516 | struct frame_info *deprecated_selected_frame; | |
517 | ||
518 | /* Return the selected frame. Always non-null (unless there isn't an | |
519 | inferior sufficient for creating a frame) in which case an error is | |
520 | thrown. */ | |
521 | ||
522 | struct frame_info * | |
523 | get_selected_frame (void) | |
524 | { | |
525 | if (deprecated_selected_frame == NULL) | |
526 | /* Hey! Don't trust this. It should really be re-finding the | |
527 | last selected frame of the currently selected thread. This, | |
528 | though, is better than nothing. */ | |
529 | select_frame (get_current_frame ()); | |
530 | /* There is always a frame. */ | |
531 | gdb_assert (deprecated_selected_frame != NULL); | |
532 | return deprecated_selected_frame; | |
533 | } | |
534 | ||
535 | /* Select frame FI (or NULL - to invalidate the current frame). */ | |
536 | ||
537 | void | |
538 | select_frame (struct frame_info *fi) | |
539 | { | |
540 | register struct symtab *s; | |
541 | ||
542 | deprecated_selected_frame = fi; | |
543 | /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the | |
544 | frame is being invalidated. */ | |
545 | if (selected_frame_level_changed_hook) | |
546 | selected_frame_level_changed_hook (frame_relative_level (fi)); | |
547 | ||
548 | /* FIXME: kseitz/2002-08-28: It would be nice to call | |
549 | selected_frame_level_changed_event right here, but due to limitations | |
550 | in the current interfaces, we would end up flooding UIs with events | |
551 | because select_frame is used extensively internally. | |
552 | ||
553 | Once we have frame-parameterized frame (and frame-related) commands, | |
554 | the event notification can be moved here, since this function will only | |
555 | be called when the users selected frame is being changed. */ | |
556 | ||
557 | /* Ensure that symbols for this frame are read in. Also, determine the | |
558 | source language of this frame, and switch to it if desired. */ | |
559 | if (fi) | |
560 | { | |
561 | s = find_pc_symtab (fi->pc); | |
562 | if (s | |
563 | && s->language != current_language->la_language | |
564 | && s->language != language_unknown | |
565 | && language_mode == language_mode_auto) | |
566 | { | |
567 | set_language (s->language); | |
568 | } | |
569 | } | |
570 | } | |
571 | ||
4c1e7e9d AC |
572 | /* Return the register saved in the simplistic ``saved_regs'' cache. |
573 | If the value isn't here AND a value is needed, try the next inner | |
574 | most frame. */ | |
575 | ||
576 | static void | |
577 | frame_saved_regs_register_unwind (struct frame_info *frame, void **cache, | |
578 | int regnum, int *optimizedp, | |
579 | enum lval_type *lvalp, CORE_ADDR *addrp, | |
580 | int *realnump, void *bufferp) | |
581 | { | |
582 | /* There is always a frame at this point. And THIS is the frame | |
583 | we're interested in. */ | |
584 | gdb_assert (frame != NULL); | |
585 | /* If we're using generic dummy frames, we'd better not be in a call | |
586 | dummy. (generic_call_dummy_register_unwind ought to have been called | |
587 | instead.) */ | |
07555a72 | 588 | gdb_assert (!(DEPRECATED_USE_GENERIC_DUMMY_FRAMES |
5e0f933e | 589 | && (get_frame_type (frame) == DUMMY_FRAME))); |
4c1e7e9d | 590 | |
8f871025 AC |
591 | /* Only (older) architectures that implement the |
592 | FRAME_INIT_SAVED_REGS method should be using this function. */ | |
593 | gdb_assert (FRAME_INIT_SAVED_REGS_P ()); | |
594 | ||
4c1e7e9d AC |
595 | /* Load the saved_regs register cache. */ |
596 | if (frame->saved_regs == NULL) | |
597 | FRAME_INIT_SAVED_REGS (frame); | |
598 | ||
599 | if (frame->saved_regs != NULL | |
600 | && frame->saved_regs[regnum] != 0) | |
601 | { | |
602 | if (regnum == SP_REGNUM) | |
603 | { | |
604 | /* SP register treated specially. */ | |
605 | *optimizedp = 0; | |
606 | *lvalp = not_lval; | |
607 | *addrp = 0; | |
608 | *realnump = -1; | |
609 | if (bufferp != NULL) | |
610 | store_address (bufferp, REGISTER_RAW_SIZE (regnum), | |
611 | frame->saved_regs[regnum]); | |
612 | } | |
613 | else | |
614 | { | |
615 | /* Any other register is saved in memory, fetch it but cache | |
616 | a local copy of its value. */ | |
617 | *optimizedp = 0; | |
618 | *lvalp = lval_memory; | |
619 | *addrp = frame->saved_regs[regnum]; | |
620 | *realnump = -1; | |
621 | if (bufferp != NULL) | |
622 | { | |
623 | #if 1 | |
624 | /* Save each register value, as it is read in, in a | |
625 | frame based cache. */ | |
626 | void **regs = (*cache); | |
627 | if (regs == NULL) | |
628 | { | |
629 | int sizeof_cache = ((NUM_REGS + NUM_PSEUDO_REGS) | |
630 | * sizeof (void *)); | |
479ab5a0 | 631 | regs = frame_obstack_zalloc (sizeof_cache); |
4c1e7e9d AC |
632 | (*cache) = regs; |
633 | } | |
634 | if (regs[regnum] == NULL) | |
635 | { | |
636 | regs[regnum] | |
479ab5a0 | 637 | = frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum)); |
4c1e7e9d AC |
638 | read_memory (frame->saved_regs[regnum], regs[regnum], |
639 | REGISTER_RAW_SIZE (regnum)); | |
640 | } | |
641 | memcpy (bufferp, regs[regnum], REGISTER_RAW_SIZE (regnum)); | |
642 | #else | |
643 | /* Read the value in from memory. */ | |
644 | read_memory (frame->saved_regs[regnum], bufferp, | |
645 | REGISTER_RAW_SIZE (regnum)); | |
646 | #endif | |
647 | } | |
648 | } | |
649 | return; | |
650 | } | |
651 | ||
652 | /* No luck, assume this and the next frame have the same register | |
653 | value. If a value is needed, pass the request on down the chain; | |
654 | otherwise just return an indication that the value is in the same | |
655 | register as the next frame. */ | |
656 | if (bufferp == NULL) | |
657 | { | |
658 | *optimizedp = 0; | |
659 | *lvalp = lval_register; | |
660 | *addrp = 0; | |
661 | *realnump = regnum; | |
662 | } | |
663 | else | |
664 | { | |
665 | frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp, | |
666 | realnump, bufferp); | |
667 | } | |
668 | } | |
669 | ||
f18c5a73 AC |
670 | static CORE_ADDR |
671 | frame_saved_regs_pc_unwind (struct frame_info *frame, void **cache) | |
672 | { | |
673 | return FRAME_SAVED_PC (frame); | |
674 | } | |
675 | ||
c170fb60 AC |
676 | static void |
677 | frame_saved_regs_id_unwind (struct frame_info *next_frame, void **cache, | |
678 | struct frame_id *id) | |
c689142b AC |
679 | { |
680 | int fromleaf; | |
c170fb60 AC |
681 | CORE_ADDR base; |
682 | CORE_ADDR pc; | |
683 | ||
684 | /* Start out by assuming it's NULL. */ | |
685 | (*id) = null_frame_id; | |
c689142b AC |
686 | |
687 | if (next_frame->next == NULL) | |
688 | /* FIXME: 2002-11-09: Frameless functions can occure anywhere in | |
689 | the frame chain, not just the inner most frame! The generic, | |
690 | per-architecture, frame code should handle this and the below | |
691 | should simply be removed. */ | |
692 | fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame); | |
693 | else | |
694 | fromleaf = 0; | |
695 | ||
696 | if (fromleaf) | |
697 | /* A frameless inner-most frame. The `FP' (which isn't an | |
698 | architecture frame-pointer register!) of the caller is the same | |
699 | as the callee. */ | |
700 | /* FIXME: 2002-11-09: There isn't any reason to special case this | |
701 | edge condition. Instead the per-architecture code should hande | |
702 | it locally. */ | |
c170fb60 | 703 | base = get_frame_base (next_frame); |
c689142b AC |
704 | else |
705 | { | |
706 | /* Two macros defined in tm.h specify the machine-dependent | |
707 | actions to be performed here. | |
708 | ||
709 | First, get the frame's chain-pointer. | |
710 | ||
711 | If that is zero, the frame is the outermost frame or a leaf | |
712 | called by the outermost frame. This means that if start | |
713 | calls main without a frame, we'll return 0 (which is fine | |
714 | anyway). | |
715 | ||
716 | Nope; there's a problem. This also returns when the current | |
717 | routine is a leaf of main. This is unacceptable. We move | |
718 | this to after the ffi test; I'd rather have backtraces from | |
719 | start go curfluy than have an abort called from main not show | |
720 | main. */ | |
c170fb60 | 721 | base = FRAME_CHAIN (next_frame); |
c689142b | 722 | |
c170fb60 AC |
723 | if (!frame_chain_valid (base, next_frame)) |
724 | return; | |
c689142b | 725 | } |
c170fb60 AC |
726 | if (base == 0) |
727 | return; | |
c689142b AC |
728 | |
729 | /* FIXME: cagney/2002-06-08: This should probably return the frame's | |
730 | function and not the PC (a.k.a. resume address). */ | |
c170fb60 AC |
731 | pc = frame_pc_unwind (next_frame); |
732 | id->pc = pc; | |
733 | id->base = base; | |
c689142b AC |
734 | } |
735 | ||
dbe9fe58 AC |
736 | static void |
737 | frame_saved_regs_pop (struct frame_info *fi, void **cache, | |
738 | struct regcache *regcache) | |
739 | { | |
dedc2a2b | 740 | gdb_assert (POP_FRAME_P ()); |
dbe9fe58 AC |
741 | POP_FRAME; |
742 | } | |
743 | ||
494cca16 | 744 | const struct frame_unwind trad_frame_unwinder = { |
dbe9fe58 | 745 | frame_saved_regs_pop, |
494cca16 AC |
746 | frame_saved_regs_pc_unwind, |
747 | frame_saved_regs_id_unwind, | |
748 | frame_saved_regs_register_unwind | |
749 | }; | |
750 | const struct frame_unwind *trad_frame_unwind = &trad_frame_unwinder; | |
751 | ||
752 | ||
4c1e7e9d AC |
753 | /* Function: get_saved_register |
754 | Find register number REGNUM relative to FRAME and put its (raw, | |
755 | target format) contents in *RAW_BUFFER. | |
756 | ||
757 | Set *OPTIMIZED if the variable was optimized out (and thus can't be | |
758 | fetched). Note that this is never set to anything other than zero | |
759 | in this implementation. | |
760 | ||
761 | Set *LVAL to lval_memory, lval_register, or not_lval, depending on | |
762 | whether the value was fetched from memory, from a register, or in a | |
763 | strange and non-modifiable way (e.g. a frame pointer which was | |
764 | calculated rather than fetched). We will use not_lval for values | |
765 | fetched from generic dummy frames. | |
766 | ||
767 | Set *ADDRP to the address, either in memory or as a REGISTER_BYTE | |
768 | offset into the registers array. If the value is stored in a dummy | |
769 | frame, set *ADDRP to zero. | |
770 | ||
771 | To use this implementation, define a function called | |
772 | "get_saved_register" in your target code, which simply passes all | |
773 | of its arguments to this function. | |
774 | ||
775 | The argument RAW_BUFFER must point to aligned memory. */ | |
776 | ||
777 | void | |
778 | deprecated_generic_get_saved_register (char *raw_buffer, int *optimized, | |
779 | CORE_ADDR *addrp, | |
780 | struct frame_info *frame, int regnum, | |
781 | enum lval_type *lval) | |
782 | { | |
783 | if (!target_has_registers) | |
784 | error ("No registers."); | |
785 | ||
8f871025 AC |
786 | gdb_assert (FRAME_INIT_SAVED_REGS_P ()); |
787 | ||
4c1e7e9d AC |
788 | /* Normal systems don't optimize out things with register numbers. */ |
789 | if (optimized != NULL) | |
790 | *optimized = 0; | |
791 | ||
792 | if (addrp) /* default assumption: not found in memory */ | |
793 | *addrp = 0; | |
794 | ||
795 | /* Note: since the current frame's registers could only have been | |
796 | saved by frames INTERIOR TO the current frame, we skip examining | |
797 | the current frame itself: otherwise, we would be getting the | |
798 | previous frame's registers which were saved by the current frame. */ | |
799 | ||
800 | while (frame && ((frame = frame->next) != NULL)) | |
801 | { | |
5e0f933e | 802 | if (get_frame_type (frame) == DUMMY_FRAME) |
4c1e7e9d AC |
803 | { |
804 | if (lval) /* found it in a CALL_DUMMY frame */ | |
805 | *lval = not_lval; | |
806 | if (raw_buffer) | |
807 | /* FIXME: cagney/2002-06-26: This should be via the | |
808 | gdbarch_register_read() method so that it, on the fly, | |
809 | constructs either a raw or pseudo register from the raw | |
810 | register cache. */ | |
811 | regcache_raw_read (generic_find_dummy_frame (frame->pc, | |
812 | frame->frame), | |
813 | regnum, raw_buffer); | |
814 | return; | |
815 | } | |
816 | ||
817 | FRAME_INIT_SAVED_REGS (frame); | |
818 | if (frame->saved_regs != NULL | |
819 | && frame->saved_regs[regnum] != 0) | |
820 | { | |
821 | if (lval) /* found it saved on the stack */ | |
822 | *lval = lval_memory; | |
823 | if (regnum == SP_REGNUM) | |
824 | { | |
825 | if (raw_buffer) /* SP register treated specially */ | |
826 | store_address (raw_buffer, REGISTER_RAW_SIZE (regnum), | |
827 | frame->saved_regs[regnum]); | |
828 | } | |
829 | else | |
830 | { | |
831 | if (addrp) /* any other register */ | |
832 | *addrp = frame->saved_regs[regnum]; | |
833 | if (raw_buffer) | |
834 | read_memory (frame->saved_regs[regnum], raw_buffer, | |
835 | REGISTER_RAW_SIZE (regnum)); | |
836 | } | |
837 | return; | |
838 | } | |
839 | } | |
840 | ||
841 | /* If we get thru the loop to this point, it means the register was | |
842 | not saved in any frame. Return the actual live-register value. */ | |
843 | ||
844 | if (lval) /* found it in a live register */ | |
845 | *lval = lval_register; | |
846 | if (addrp) | |
847 | *addrp = REGISTER_BYTE (regnum); | |
848 | if (raw_buffer) | |
849 | deprecated_read_register_gen (regnum, raw_buffer); | |
850 | } | |
851 | ||
eb4f72c5 AC |
852 | /* Determine the frame's type based on its PC. */ |
853 | ||
854 | static enum frame_type | |
855 | frame_type_from_pc (CORE_ADDR pc) | |
856 | { | |
857 | /* FIXME: cagney/2002-11-24: Can't yet directly call | |
858 | pc_in_dummy_frame() as some architectures don't set | |
859 | PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the | |
860 | latter is implemented by simply calling pc_in_dummy_frame). */ | |
861 | if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES | |
862 | && DEPRECATED_PC_IN_CALL_DUMMY (pc, 0, 0)) | |
863 | return DUMMY_FRAME; | |
864 | else | |
865 | { | |
866 | char *name; | |
867 | find_pc_partial_function (pc, &name, NULL, NULL); | |
868 | if (PC_IN_SIGTRAMP (pc, name)) | |
869 | return SIGTRAMP_FRAME; | |
870 | else | |
871 | return NORMAL_FRAME; | |
872 | } | |
873 | } | |
874 | ||
4c1e7e9d AC |
875 | /* Create an arbitrary (i.e. address specified by user) or innermost frame. |
876 | Always returns a non-NULL value. */ | |
877 | ||
878 | struct frame_info * | |
879 | create_new_frame (CORE_ADDR addr, CORE_ADDR pc) | |
880 | { | |
881 | struct frame_info *fi; | |
4c1e7e9d | 882 | |
479ab5a0 | 883 | fi = frame_obstack_zalloc (sizeof (struct frame_info)); |
4c1e7e9d AC |
884 | |
885 | fi->frame = addr; | |
886 | fi->pc = pc; | |
eb4f72c5 | 887 | fi->type = frame_type_from_pc (pc); |
4c1e7e9d AC |
888 | |
889 | if (INIT_EXTRA_FRAME_INFO_P ()) | |
890 | INIT_EXTRA_FRAME_INFO (0, fi); | |
891 | ||
892 | /* Select/initialize an unwind function. */ | |
494cca16 | 893 | fi->unwind = frame_unwind_find_by_pc (current_gdbarch, fi->pc); |
4c1e7e9d AC |
894 | |
895 | return fi; | |
896 | } | |
897 | ||
898 | /* Return the frame that FRAME calls (NULL if FRAME is the innermost | |
899 | frame). */ | |
900 | ||
901 | struct frame_info * | |
902 | get_next_frame (struct frame_info *frame) | |
903 | { | |
904 | return frame->next; | |
905 | } | |
906 | ||
907 | /* Flush the entire frame cache. */ | |
908 | ||
909 | void | |
910 | flush_cached_frames (void) | |
911 | { | |
912 | /* Since we can't really be sure what the first object allocated was */ | |
913 | obstack_free (&frame_cache_obstack, 0); | |
914 | obstack_init (&frame_cache_obstack); | |
915 | ||
916 | current_frame = NULL; /* Invalidate cache */ | |
917 | select_frame (NULL); | |
918 | annotate_frames_invalid (); | |
919 | } | |
920 | ||
921 | /* Flush the frame cache, and start a new one if necessary. */ | |
922 | ||
923 | void | |
924 | reinit_frame_cache (void) | |
925 | { | |
926 | flush_cached_frames (); | |
927 | ||
928 | /* FIXME: The inferior_ptid test is wrong if there is a corefile. */ | |
929 | if (PIDGET (inferior_ptid) != 0) | |
930 | { | |
931 | select_frame (get_current_frame ()); | |
932 | } | |
933 | } | |
934 | ||
eb4f72c5 AC |
935 | /* Create the previous frame using the deprecated methods |
936 | INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */ | |
4c1e7e9d | 937 | |
eb4f72c5 AC |
938 | static struct frame_info * |
939 | legacy_get_prev_frame (struct frame_info *next_frame) | |
4c1e7e9d AC |
940 | { |
941 | CORE_ADDR address = 0; | |
942 | struct frame_info *prev; | |
95adb866 | 943 | int fromleaf; |
4c1e7e9d | 944 | |
eb4f72c5 AC |
945 | /* This code only works on normal frames. A sentinel frame, where |
946 | the level is -1, should never reach this code. */ | |
947 | gdb_assert (next_frame->level >= 0); | |
4c1e7e9d AC |
948 | |
949 | /* On some machines it is possible to call a function without | |
950 | setting up a stack frame for it. On these machines, we | |
951 | define this macro to take two args; a frameinfo pointer | |
952 | identifying a frame and a variable to set or clear if it is | |
953 | or isn't leafless. */ | |
954 | ||
955 | /* Still don't want to worry about this except on the innermost | |
95adb866 AC |
956 | frame. This macro will set FROMLEAF if NEXT_FRAME is a frameless |
957 | function invocation. */ | |
eb4f72c5 | 958 | if (next_frame->level == 0) |
95adb866 AC |
959 | /* FIXME: 2002-11-09: Frameless functions can occure anywhere in |
960 | the frame chain, not just the inner most frame! The generic, | |
961 | per-architecture, frame code should handle this and the below | |
962 | should simply be removed. */ | |
963 | fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame); | |
964 | else | |
965 | fromleaf = 0; | |
966 | ||
967 | if (fromleaf) | |
968 | /* A frameless inner-most frame. The `FP' (which isn't an | |
969 | architecture frame-pointer register!) of the caller is the same | |
970 | as the callee. */ | |
971 | /* FIXME: 2002-11-09: There isn't any reason to special case this | |
972 | edge condition. Instead the per-architecture code should hande | |
973 | it locally. */ | |
c193f6ac | 974 | address = get_frame_base (next_frame); |
95adb866 | 975 | else |
4c1e7e9d AC |
976 | { |
977 | /* Two macros defined in tm.h specify the machine-dependent | |
978 | actions to be performed here. | |
95adb866 | 979 | |
4c1e7e9d | 980 | First, get the frame's chain-pointer. |
95adb866 | 981 | |
4c1e7e9d AC |
982 | If that is zero, the frame is the outermost frame or a leaf |
983 | called by the outermost frame. This means that if start | |
984 | calls main without a frame, we'll return 0 (which is fine | |
985 | anyway). | |
986 | ||
987 | Nope; there's a problem. This also returns when the current | |
988 | routine is a leaf of main. This is unacceptable. We move | |
989 | this to after the ffi test; I'd rather have backtraces from | |
990 | start go curfluy than have an abort called from main not show | |
991 | main. */ | |
992 | address = FRAME_CHAIN (next_frame); | |
993 | ||
51603483 | 994 | if (!frame_chain_valid (address, next_frame)) |
4c1e7e9d AC |
995 | return 0; |
996 | } | |
997 | if (address == 0) | |
998 | return 0; | |
999 | ||
95adb866 | 1000 | /* Create an initially zero previous frame. */ |
479ab5a0 | 1001 | prev = frame_obstack_zalloc (sizeof (struct frame_info)); |
4c1e7e9d | 1002 | |
95adb866 AC |
1003 | /* Link it in. */ |
1004 | next_frame->prev = prev; | |
4c1e7e9d AC |
1005 | prev->next = next_frame; |
1006 | prev->frame = address; | |
1007 | prev->level = next_frame->level + 1; | |
5a203e44 AC |
1008 | /* FIXME: cagney/2002-11-18: Should be setting the frame's type |
1009 | here, before anything else, and not last. Various INIT functions | |
1010 | are full of work-arounds for the frames type not being set | |
1011 | correctly from the word go. Ulgh! */ | |
1012 | prev->type = NORMAL_FRAME; | |
4c1e7e9d | 1013 | |
95adb866 | 1014 | /* This change should not be needed, FIXME! We should determine |
a5afb99f AC |
1015 | whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen |
1016 | after INIT_EXTRA_FRAME_INFO and come up with a simple way to | |
1017 | express what goes on here. | |
95adb866 AC |
1018 | |
1019 | INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame | |
1020 | (where the PC is already set up) and here (where it isn't). | |
a5afb99f | 1021 | DEPRECATED_INIT_FRAME_PC is only called from here, always after |
95adb866 AC |
1022 | INIT_EXTRA_FRAME_INFO. |
1023 | ||
1024 | The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the | |
1025 | PC value (which hasn't been set yet). Some other machines appear | |
1026 | to require INIT_EXTRA_FRAME_INFO before they can do | |
a5afb99f | 1027 | DEPRECATED_INIT_FRAME_PC. Phoo. |
95adb866 | 1028 | |
2ca6c561 AC |
1029 | We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more |
1030 | complication to an already overcomplicated part of GDB. | |
1031 | gnu@cygnus.com, 15Sep92. | |
95adb866 | 1032 | |
a5afb99f | 1033 | Assuming that some machines need DEPRECATED_INIT_FRAME_PC after |
95adb866 AC |
1034 | INIT_EXTRA_FRAME_INFO, one possible scheme: |
1035 | ||
1036 | SETUP_INNERMOST_FRAME(): Default version is just create_new_frame | |
1037 | (read_fp ()), read_pc ()). Machines with extra frame info would | |
1038 | do that (or the local equivalent) and then set the extra fields. | |
1039 | ||
1040 | SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that | |
1041 | create_new_frame would no longer init extra frame info; | |
1042 | SETUP_ARBITRARY_FRAME would have to do that. | |
1043 | ||
1044 | INIT_PREV_FRAME(fromleaf, prev) Replace INIT_EXTRA_FRAME_INFO and | |
a5afb99f AC |
1045 | DEPRECATED_INIT_FRAME_PC. This should also return a flag saying |
1046 | whether to keep the new frame, or whether to discard it, because | |
1047 | on some machines (e.g. mips) it is really awkward to have | |
95adb866 AC |
1048 | FRAME_CHAIN_VALID called *before* INIT_EXTRA_FRAME_INFO (there is |
1049 | no good way to get information deduced in FRAME_CHAIN_VALID into | |
1050 | the extra fields of the new frame). std_frame_pc(fromleaf, prev) | |
1051 | ||
1052 | This is the default setting for INIT_PREV_FRAME. It just does | |
a5afb99f AC |
1053 | what the default DEPRECATED_INIT_FRAME_PC does. Some machines |
1054 | will call it from INIT_PREV_FRAME (either at the beginning, the | |
1055 | end, or in the middle). Some machines won't use it. | |
95adb866 AC |
1056 | |
1057 | kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */ | |
1058 | ||
1059 | /* NOTE: cagney/2002-11-09: Just ignore the above! There is no | |
1060 | reason for things to be this complicated. | |
1061 | ||
1062 | The trick is to assume that there is always a frame. Instead of | |
1063 | special casing the inner-most frame, create fake frame | |
1064 | (containing the hardware registers) that is inner to the | |
1065 | user-visible inner-most frame (...) and then unwind from that. | |
1066 | That way architecture code can use use the standard | |
1067 | frame_XX_unwind() functions and not differentiate between the | |
1068 | inner most and any other case. | |
1069 | ||
1070 | Since there is always a frame to unwind from, there is always | |
1071 | somewhere (NEXT_FRAME) to store all the info needed to construct | |
1072 | a new (previous) frame without having to first create it. This | |
1073 | means that the convolution below - needing to carefully order a | |
1074 | frame's initialization - isn't needed. | |
1075 | ||
1076 | The irony here though, is that FRAME_CHAIN(), at least for a more | |
1077 | up-to-date architecture, always calls FRAME_SAVED_PC(), and | |
1078 | FRAME_SAVED_PC() computes the PC but without first needing the | |
1079 | frame! Instead of the convolution below, we could have simply | |
1080 | called FRAME_SAVED_PC() and been done with it! Note that | |
1081 | FRAME_SAVED_PC() is being superseed by frame_pc_unwind() and that | |
1082 | function does have somewhere to cache that PC value. */ | |
4c1e7e9d | 1083 | |
2ca6c561 | 1084 | if (DEPRECATED_INIT_FRAME_PC_FIRST_P ()) |
97f46953 | 1085 | prev->pc = (DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf, prev)); |
4c1e7e9d AC |
1086 | |
1087 | if (INIT_EXTRA_FRAME_INFO_P ()) | |
1088 | INIT_EXTRA_FRAME_INFO (fromleaf, prev); | |
1089 | ||
1090 | /* This entry is in the frame queue now, which is good since | |
95adb866 AC |
1091 | FRAME_SAVED_PC may use that queue to figure out its value (see |
1092 | tm-sparc.h). We want the pc saved in the inferior frame. */ | |
a5afb99f AC |
1093 | if (DEPRECATED_INIT_FRAME_PC_P ()) |
1094 | prev->pc = DEPRECATED_INIT_FRAME_PC (fromleaf, prev); | |
4c1e7e9d | 1095 | |
95adb866 AC |
1096 | /* If ->frame and ->pc are unchanged, we are in the process of |
1097 | getting ourselves into an infinite backtrace. Some architectures | |
1098 | check this in FRAME_CHAIN or thereabouts, but it seems like there | |
1099 | is no reason this can't be an architecture-independent check. */ | |
1100 | if (prev->frame == next_frame->frame | |
1101 | && prev->pc == next_frame->pc) | |
4c1e7e9d | 1102 | { |
95adb866 AC |
1103 | next_frame->prev = NULL; |
1104 | obstack_free (&frame_cache_obstack, prev); | |
1105 | return NULL; | |
4c1e7e9d AC |
1106 | } |
1107 | ||
1108 | /* Initialize the code used to unwind the frame PREV based on the PC | |
1109 | (and probably other architectural information). The PC lets you | |
1110 | check things like the debug info at that point (dwarf2cfi?) and | |
1111 | use that to decide how the frame should be unwound. */ | |
494cca16 | 1112 | prev->unwind = frame_unwind_find_by_pc (current_gdbarch, prev->pc); |
4c1e7e9d | 1113 | |
5a203e44 AC |
1114 | /* NOTE: cagney/2002-11-18: The code segments, found in |
1115 | create_new_frame and get_prev_frame(), that initializes the | |
1116 | frames type is subtly different. The latter only updates ->type | |
1117 | when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops | |
1118 | get_prev_frame() overriding the frame's type when the INIT code | |
1119 | has previously set it. This is really somewhat bogus. The | |
1120 | initialization, as seen in create_new_frame(), should occur | |
1121 | before the INIT function has been called. */ | |
07555a72 | 1122 | if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES |
ae45cd16 AC |
1123 | && (DEPRECATED_PC_IN_CALL_DUMMY_P () |
1124 | ? DEPRECATED_PC_IN_CALL_DUMMY (prev->pc, 0, 0) | |
1125 | : pc_in_dummy_frame (prev->pc))) | |
5a203e44 AC |
1126 | prev->type = DUMMY_FRAME; |
1127 | else | |
1128 | { | |
1129 | /* FIXME: cagney/2002-11-10: This should be moved to before the | |
1130 | INIT code above so that the INIT code knows what the frame's | |
1131 | type is (in fact, for a [generic] dummy-frame, the type can | |
1132 | be set and then the entire initialization can be skipped. | |
1133 | Unforunatly, its the INIT code that sets the PC (Hmm, catch | |
1134 | 22). */ | |
1135 | char *name; | |
1136 | find_pc_partial_function (prev->pc, &name, NULL, NULL); | |
1137 | if (PC_IN_SIGTRAMP (prev->pc, name)) | |
1138 | prev->type = SIGTRAMP_FRAME; | |
1139 | /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some | |
1140 | architectures are forcing the frame's type in INIT so we | |
1141 | don't want to override it here. Remember, NORMAL_FRAME == 0, | |
1142 | so it all works (just :-/). Once this initialization is | |
1143 | moved to the start of this function, all this nastness will | |
1144 | go away. */ | |
1145 | } | |
4c1e7e9d AC |
1146 | |
1147 | return prev; | |
1148 | } | |
1149 | ||
eb4f72c5 AC |
1150 | /* Return a structure containing various interesting information |
1151 | about the frame that called NEXT_FRAME. Returns NULL | |
1152 | if there is no such frame. */ | |
1153 | ||
1154 | struct frame_info * | |
1155 | get_prev_frame (struct frame_info *next_frame) | |
1156 | { | |
1157 | struct frame_info *prev_frame; | |
1158 | ||
1159 | /* Return the inner-most frame, when the caller passes in NULL. */ | |
1160 | /* NOTE: cagney/2002-11-09: Not sure how this would happen. The | |
1161 | caller should have previously obtained a valid frame using | |
1162 | get_selected_frame() and then called this code - only possibility | |
1163 | I can think of is code behaving badly. | |
1164 | ||
1165 | NOTE: cagney/2003-01-10: Talk about code behaving badly. Check | |
1166 | block_innermost_frame(). It does the sequence: frame = NULL; | |
1167 | while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why | |
1168 | it couldn't be written better, I don't know. | |
1169 | ||
1170 | NOTE: cagney/2003-01-11: I suspect what is happening is | |
1171 | block_innermost_frame() is, when the target has no state | |
1172 | (registers, memory, ...), still calling this function. The | |
1173 | assumption being that this function will return NULL indicating | |
1174 | that a frame isn't possible, rather than checking that the target | |
1175 | has state and then calling get_current_frame() and | |
1176 | get_prev_frame(). This is a guess mind. */ | |
1177 | if (next_frame == NULL) | |
1178 | { | |
1179 | /* NOTE: cagney/2002-11-09: There was a code segment here that | |
1180 | would error out when CURRENT_FRAME was NULL. The comment | |
1181 | that went with it made the claim ... | |
1182 | ||
1183 | ``This screws value_of_variable, which just wants a nice | |
1184 | clean NULL return from block_innermost_frame if there are no | |
1185 | frames. I don't think I've ever seen this message happen | |
1186 | otherwise. And returning NULL here is a perfectly legitimate | |
1187 | thing to do.'' | |
1188 | ||
1189 | Per the above, this code shouldn't even be called with a NULL | |
1190 | NEXT_FRAME. */ | |
1191 | return current_frame; | |
1192 | } | |
1193 | ||
1194 | /* There is always a frame. If this assertion fails, suspect that | |
1195 | something should be calling get_selected_frame() or | |
1196 | get_current_frame(). */ | |
1197 | gdb_assert (next_frame != NULL); | |
1198 | ||
1199 | if (next_frame->level >= 0 | |
1200 | && !backtrace_below_main | |
1201 | && inside_main_func (get_frame_pc (next_frame))) | |
1202 | /* Don't unwind past main(), bug always unwind the sentinel frame. | |
1203 | Note, this is done _before_ the frame has been marked as | |
1204 | previously unwound. That way if the user later decides to | |
1205 | allow unwinds past main(), that just happens. */ | |
1206 | return NULL; | |
1207 | ||
1208 | /* Only try to do the unwind once. */ | |
1209 | if (next_frame->prev_p) | |
1210 | return next_frame->prev; | |
1211 | next_frame->prev_p = 1; | |
1212 | ||
1213 | /* If we're inside the entry file, it isn't valid. */ | |
1214 | /* NOTE: drow/2002-12-25: should there be a way to disable this | |
1215 | check? It assumes a single small entry file, and the way some | |
1216 | debug readers (e.g. dbxread) figure out which object is the | |
1217 | entry file is somewhat hokey. */ | |
1218 | /* NOTE: cagney/2003-01-10: If there is a way of disabling this test | |
1219 | then it should probably be moved to before the ->prev_p test, | |
1220 | above. */ | |
1221 | if (inside_entry_file (get_frame_pc (next_frame))) | |
1222 | return NULL; | |
1223 | ||
1224 | /* If any of the old frame initialization methods are around, use | |
1225 | the legacy get_prev_frame method. Just don't try to unwind a | |
1226 | sentinel frame using that method - it doesn't work. All sentinal | |
1227 | frames use the new unwind code. */ | |
1228 | if ((DEPRECATED_INIT_FRAME_PC_P () | |
1229 | || DEPRECATED_INIT_FRAME_PC_FIRST_P () | |
1230 | || INIT_EXTRA_FRAME_INFO_P ()) | |
1231 | && next_frame->level >= 0) | |
1232 | return legacy_get_prev_frame (next_frame); | |
1233 | ||
1234 | /* Allocate the new frame but do not wire it in to the frame chain. | |
1235 | Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along | |
1236 | frame->next to pull some fancy tricks (of course such code is, by | |
1237 | definition, recursive). Try to prevent it. | |
1238 | ||
1239 | There is no reason to worry about memory leaks, should the | |
1240 | remainder of the function fail. The allocated memory will be | |
1241 | quickly reclaimed when the frame cache is flushed, and the `we've | |
1242 | been here before' check above will stop repeated memory | |
1243 | allocation calls. */ | |
1244 | prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info); | |
1245 | prev_frame->level = next_frame->level + 1; | |
1246 | ||
1247 | /* Try to unwind the PC. If that doesn't work, assume we've reached | |
1248 | the oldest frame and simply return. Is there a better sentinal | |
1249 | value? The unwound PC value is then used to initialize the new | |
1250 | previous frame's type. | |
1251 | ||
1252 | Note that the pc-unwind is intentionally performed before the | |
1253 | frame chain. This is ok since, for old targets, both | |
1254 | frame_pc_unwind (nee, FRAME_SAVED_PC) and FRAME_CHAIN()) assume | |
1255 | NEXT_FRAME's data structures have already been initialized (using | |
1256 | INIT_EXTRA_FRAME_INFO) and hence the call order doesn't matter. | |
1257 | ||
1258 | By unwinding the PC first, it becomes possible to, in the case of | |
1259 | a dummy frame, avoid also unwinding the frame ID. This is | |
1260 | because (well ignoring the PPC) a dummy frame can be located | |
1261 | using NEXT_FRAME's frame ID. */ | |
1262 | ||
1263 | prev_frame->pc = frame_pc_unwind (next_frame); | |
1264 | if (prev_frame->pc == 0) | |
1265 | /* The allocated PREV_FRAME will be reclaimed when the frame | |
1266 | obstack is next purged. */ | |
1267 | return NULL; | |
1268 | prev_frame->type = frame_type_from_pc (prev_frame->pc); | |
1269 | ||
1270 | /* Set the unwind functions based on that identified PC. */ | |
1271 | prev_frame->unwind = frame_unwind_find_by_pc (current_gdbarch, | |
1272 | prev_frame->pc); | |
1273 | ||
1274 | /* FIXME: cagney/2003-01-13: A dummy frame doesn't need to unwind | |
1275 | the frame ID because the frame ID comes from the previous frame. | |
1276 | The other frames do though. True? */ | |
1277 | { | |
1278 | /* FIXME: cagney/2002-12-18: Instead of this hack, should just | |
1279 | save the frame ID directly. */ | |
1280 | struct frame_id id = frame_id_unwind (next_frame); | |
1281 | if (!frame_id_p (id)) | |
1282 | return NULL; | |
1283 | prev_frame->frame = id.base; | |
1284 | } | |
1285 | ||
1286 | /* Link it in. */ | |
1287 | next_frame->prev = prev_frame; | |
1288 | prev_frame->next = next_frame; | |
1289 | ||
1290 | /* FIXME: cagney/2002-01-19: This call will go away. Instead of | |
1291 | initializing extra info, all frames will use the frame_cache | |
1292 | (passed to the unwind functions) to store additional frame info. | |
1293 | Unfortunatly legacy targets can't use legacy_get_prev_frame() to | |
1294 | unwind the sentinel frame and, consequently, are forced to take | |
1295 | this code path and rely on the below call to INIT_EXTR_FRAME_INFO | |
1296 | to initialize the inner-most frame. */ | |
1297 | if (INIT_EXTRA_FRAME_INFO_P ()) | |
1298 | { | |
1299 | gdb_assert (prev_frame->level == 0); | |
1300 | INIT_EXTRA_FRAME_INFO (0, prev_frame); | |
1301 | } | |
1302 | ||
1303 | return prev_frame; | |
1304 | } | |
1305 | ||
4c1e7e9d AC |
1306 | CORE_ADDR |
1307 | get_frame_pc (struct frame_info *frame) | |
1308 | { | |
1309 | return frame->pc; | |
1310 | } | |
1311 | ||
1058bca7 AC |
1312 | static int |
1313 | pc_notcurrent (struct frame_info *frame) | |
1314 | { | |
1315 | /* If FRAME is not the innermost frame, that normally means that | |
1316 | FRAME->pc points at the return instruction (which is *after* the | |
1317 | call instruction), and we want to get the line containing the | |
1318 | call (because the call is where the user thinks the program is). | |
1319 | However, if the next frame is either a SIGTRAMP_FRAME or a | |
1320 | DUMMY_FRAME, then the next frame will contain a saved interrupt | |
1321 | PC and such a PC indicates the current (rather than next) | |
1322 | instruction/line, consequently, for such cases, want to get the | |
1323 | line containing fi->pc. */ | |
1324 | struct frame_info *next = get_next_frame (frame); | |
1325 | int notcurrent = (next != NULL && get_frame_type (next) == NORMAL_FRAME); | |
1326 | return notcurrent; | |
1327 | } | |
1328 | ||
1329 | void | |
1330 | find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal) | |
1331 | { | |
1332 | (*sal) = find_pc_line (frame->pc, pc_notcurrent (frame)); | |
1333 | } | |
1334 | ||
c193f6ac AC |
1335 | /* Per "frame.h", return the ``address'' of the frame. Code should |
1336 | really be using get_frame_id(). */ | |
1337 | CORE_ADDR | |
1338 | get_frame_base (struct frame_info *fi) | |
1339 | { | |
1340 | return fi->frame; | |
1341 | } | |
1342 | ||
85cf597a AC |
1343 | /* Level of the selected frame: 0 for innermost, 1 for its caller, ... |
1344 | or -1 for a NULL frame. */ | |
1345 | ||
1346 | int | |
1347 | frame_relative_level (struct frame_info *fi) | |
1348 | { | |
1349 | if (fi == NULL) | |
1350 | return -1; | |
1351 | else | |
1352 | return fi->level; | |
1353 | } | |
1354 | ||
5a203e44 AC |
1355 | enum frame_type |
1356 | get_frame_type (struct frame_info *frame) | |
1357 | { | |
1358 | /* Some targets still don't use [generic] dummy frames. Catch them | |
1359 | here. */ | |
07555a72 | 1360 | if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES |
5a203e44 AC |
1361 | && deprecated_frame_in_dummy (frame)) |
1362 | return DUMMY_FRAME; | |
1363 | return frame->type; | |
1364 | } | |
1365 | ||
1366 | void | |
1367 | deprecated_set_frame_type (struct frame_info *frame, enum frame_type type) | |
1368 | { | |
1369 | /* Arrrg! See comment in "frame.h". */ | |
1370 | frame->type = type; | |
1371 | } | |
1372 | ||
4c1e7e9d AC |
1373 | #ifdef FRAME_FIND_SAVED_REGS |
1374 | /* XXX - deprecated. This is a compatibility function for targets | |
1375 | that do not yet implement FRAME_INIT_SAVED_REGS. */ | |
1376 | /* Find the addresses in which registers are saved in FRAME. */ | |
1377 | ||
1378 | void | |
95486978 AC |
1379 | deprecated_get_frame_saved_regs (struct frame_info *frame, |
1380 | struct frame_saved_regs *saved_regs_addr) | |
4c1e7e9d AC |
1381 | { |
1382 | if (frame->saved_regs == NULL) | |
1383 | { | |
1384 | frame->saved_regs = (CORE_ADDR *) | |
479ab5a0 | 1385 | frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS); |
4c1e7e9d AC |
1386 | } |
1387 | if (saved_regs_addr == NULL) | |
1388 | { | |
1389 | struct frame_saved_regs saved_regs; | |
1390 | FRAME_FIND_SAVED_REGS (frame, saved_regs); | |
1391 | memcpy (frame->saved_regs, &saved_regs, SIZEOF_FRAME_SAVED_REGS); | |
1392 | } | |
1393 | else | |
1394 | { | |
1395 | FRAME_FIND_SAVED_REGS (frame, *saved_regs_addr); | |
1396 | memcpy (frame->saved_regs, saved_regs_addr, SIZEOF_FRAME_SAVED_REGS); | |
1397 | } | |
1398 | } | |
1399 | #endif | |
1400 | ||
0394eb2a AC |
1401 | struct frame_extra_info * |
1402 | get_frame_extra_info (struct frame_info *fi) | |
1403 | { | |
1404 | return fi->extra_info; | |
1405 | } | |
1406 | ||
2c517d0e AC |
1407 | struct frame_extra_info * |
1408 | frame_extra_info_zalloc (struct frame_info *fi, long size) | |
1409 | { | |
479ab5a0 | 1410 | fi->extra_info = frame_obstack_zalloc (size); |
2c517d0e AC |
1411 | return fi->extra_info; |
1412 | } | |
1413 | ||
b87efeee | 1414 | void |
2f107107 | 1415 | deprecated_update_frame_pc_hack (struct frame_info *frame, CORE_ADDR pc) |
b87efeee | 1416 | { |
2f107107 AC |
1417 | /* See comment in "frame.h". */ |
1418 | frame->pc = pc; | |
1419 | } | |
1420 | ||
1421 | void | |
1422 | deprecated_update_frame_base_hack (struct frame_info *frame, CORE_ADDR base) | |
1423 | { | |
1424 | /* See comment in "frame.h". */ | |
1425 | frame->frame = base; | |
b87efeee AC |
1426 | } |
1427 | ||
c8b8a898 AC |
1428 | void |
1429 | deprecated_set_frame_saved_regs_hack (struct frame_info *frame, | |
1430 | CORE_ADDR *saved_regs) | |
1431 | { | |
1432 | frame->saved_regs = saved_regs; | |
1433 | } | |
1434 | ||
1435 | void | |
1436 | deprecated_set_frame_extra_info_hack (struct frame_info *frame, | |
1437 | struct frame_extra_info *extra_info) | |
1438 | { | |
1439 | frame->extra_info = extra_info; | |
1440 | } | |
1441 | ||
483d36b2 AC |
1442 | void |
1443 | deprecated_set_frame_next_hack (struct frame_info *fi, | |
1444 | struct frame_info *next) | |
1445 | { | |
1446 | fi->next = next; | |
1447 | } | |
1448 | ||
1449 | void | |
1450 | deprecated_set_frame_prev_hack (struct frame_info *fi, | |
1451 | struct frame_info *prev) | |
1452 | { | |
1453 | fi->prev = prev; | |
1454 | } | |
1455 | ||
2d75187b AC |
1456 | struct context * |
1457 | deprecated_get_frame_context (struct frame_info *fi) | |
1458 | { | |
1459 | return fi->context; | |
1460 | } | |
1461 | ||
1462 | void | |
1463 | deprecated_set_frame_context (struct frame_info *fi, | |
1464 | struct context *context) | |
1465 | { | |
1466 | fi->context = context; | |
1467 | } | |
1468 | ||
c8b8a898 AC |
1469 | struct frame_info * |
1470 | deprecated_frame_xmalloc (void) | |
1471 | { | |
1472 | struct frame_info *frame = XMALLOC (struct frame_info); | |
1473 | memset (frame, 0, sizeof (struct frame_info)); | |
1474 | return frame; | |
1475 | } | |
1476 | ||
f6c609c4 AC |
1477 | struct frame_info * |
1478 | deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs, | |
1479 | long sizeof_extra_info) | |
1480 | { | |
1481 | struct frame_info *frame = deprecated_frame_xmalloc (); | |
1482 | make_cleanup (xfree, frame); | |
1483 | if (sizeof_saved_regs > 0) | |
1484 | { | |
1485 | frame->saved_regs = xcalloc (1, sizeof_saved_regs); | |
1486 | make_cleanup (xfree, frame->saved_regs); | |
1487 | } | |
1488 | if (sizeof_extra_info > 0) | |
1489 | { | |
1490 | frame->extra_info = xcalloc (1, sizeof_extra_info); | |
1491 | make_cleanup (xfree, frame->extra_info); | |
1492 | } | |
1493 | return frame; | |
1494 | } | |
c8b8a898 | 1495 | |
4c1e7e9d AC |
1496 | void |
1497 | _initialize_frame (void) | |
1498 | { | |
1499 | obstack_init (&frame_cache_obstack); | |
eb4f72c5 AC |
1500 | |
1501 | /* FIXME: cagney/2003-01-19: This command needs a rename. Suggest | |
1502 | `set backtrace {past,beyond,...}-main'. Also suggest adding `set | |
1503 | backtrace ...-start' to control backtraces past start. The | |
1504 | problem with `below' is that it stops the `up' command. */ | |
1505 | ||
1506 | add_setshow_boolean_cmd ("backtrace-below-main", class_obscure, | |
1507 | &backtrace_below_main, "\ | |
1508 | Set whether backtraces should continue past \"main\".\n\ | |
1509 | Normally the caller of \"main\" is not of interest, so GDB will terminate\n\ | |
1510 | the backtrace at \"main\". Set this variable if you need to see the rest\n\ | |
1511 | of the stack trace.", "\ | |
1512 | Show whether backtraces should continue past \"main\".\n\ | |
1513 | Normally the caller of \"main\" is not of interest, so GDB will terminate\n\ | |
1514 | the backtrace at \"main\". Set this variable if you need to see the rest\n\ | |
1515 | of the stack trace.", | |
1516 | NULL, NULL, &setlist, &showlist); | |
4c1e7e9d | 1517 | } |