* elf32-ppc.c: Formatting.
[deliverable/binutils-gdb.git] / gdb / frame.c
CommitLineData
4f460812 1/* Cache and manage frames for GDB, the GNU debugger.
96cb11df
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2
3 Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000,
51603483 4 2001, 2002, 2003 Free Software Foundation, Inc.
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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"
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30#include "gdb_string.h"
31#include "builtin-regs.h"
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32#include "gdb_obstack.h"
33#include "dummy-frame.h"
a94dd1fd 34#include "sentinel-frame.h"
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35#include "gdbcore.h"
36#include "annotate.h"
6e7f8b9c 37#include "language.h"
494cca16 38#include "frame-unwind.h"
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39#include "command.h"
40#include "gdbcmd.h"
41
42/* Flag to indicate whether backtraces should stop at main. */
43
44static int backtrace_below_main;
d65fe839 45
7a424e99 46/* Return a frame uniq ID that can be used to, later, re-find the
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47 frame. */
48
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49struct frame_id
50get_frame_id (struct frame_info *fi)
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51{
52 if (fi == NULL)
53 {
7a424e99 54 return null_frame_id;
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55 }
56 else
57 {
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58 struct frame_id id;
59 id.base = fi->frame;
60 id.pc = fi->pc;
61 return id;
101dcfbe
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62 }
63}
64
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65const struct frame_id null_frame_id; /* All zeros. */
66
67struct frame_id
68frame_id_build (CORE_ADDR base, CORE_ADDR func_or_pc)
69{
70 struct frame_id id;
71 id.base = base;
72 id.pc = func_or_pc;
73 return id;
74}
75
76int
77frame_id_p (struct frame_id l)
78{
79 /* The .func can be NULL but the .base cannot. */
80 return (l.base != 0);
81}
82
83int
84frame_id_eq (struct frame_id l, struct frame_id r)
85{
86 /* If .base is different, the frames are different. */
87 if (l.base != r.base)
88 return 0;
89 /* Add a test to check that the frame ID's are for the same function
90 here. */
91 return 1;
92}
93
94int
95frame_id_inner (struct frame_id l, struct frame_id r)
96{
97 /* Only return non-zero when strictly inner than. Note that, per
98 comment in "frame.h", there is some fuzz here. Frameless
99 functions are not strictly inner than (same .base but different
100 .func). */
101 return INNER_THAN (l.base, r.base);
102}
103
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104struct frame_info *
105frame_find_by_id (struct frame_id id)
106{
107 struct frame_info *frame;
108
109 /* ZERO denotes the null frame, let the caller decide what to do
110 about it. Should it instead return get_current_frame()? */
7a424e99 111 if (!frame_id_p (id))
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112 return NULL;
113
114 for (frame = get_current_frame ();
115 frame != NULL;
116 frame = get_prev_frame (frame))
117 {
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118 struct frame_id this = get_frame_id (frame);
119 if (frame_id_eq (id, this))
120 /* An exact match. */
121 return frame;
122 if (frame_id_inner (id, this))
123 /* Gone to far. */
101dcfbe 124 return NULL;
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125 /* Either, we're not yet gone far enough out along the frame
126 chain (inner(this,id), or we're comparing frameless functions
127 (same .base, different .func, no test available). Struggle
128 on until we've definitly gone to far. */
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129 }
130 return NULL;
131}
132
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133CORE_ADDR
134frame_pc_unwind (struct frame_info *frame)
135{
136 if (!frame->pc_unwind_cache_p)
137 {
494cca16 138 frame->pc_unwind_cache = frame->unwind->pc (frame, &frame->unwind_cache);
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139 frame->pc_unwind_cache_p = 1;
140 }
141 return frame->pc_unwind_cache;
142}
143
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144struct frame_id
145frame_id_unwind (struct frame_info *frame)
146{
147 if (!frame->id_unwind_cache_p)
148 {
494cca16 149 frame->unwind->id (frame, &frame->unwind_cache, &frame->id_unwind_cache);
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150 frame->id_unwind_cache_p = 1;
151 }
152 return frame->id_unwind_cache;
153}
154
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155void
156frame_pop (struct frame_info *frame)
157{
158 /* FIXME: cagney/2003-01-18: There is probably a chicken-egg problem
159 with passing in current_regcache. The pop function needs to be
160 written carefully so as to not overwrite registers whose [old]
161 values are needed to restore other registers. Instead, this code
162 should pass in a scratch cache and, as a second step, restore the
163 registers using that. */
164 frame->unwind->pop (frame, &frame->unwind_cache, current_regcache);
165 flush_cached_frames ();
166}
c689142b 167
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168void
169frame_register_unwind (struct frame_info *frame, int regnum,
170 int *optimizedp, enum lval_type *lvalp,
171 CORE_ADDR *addrp, int *realnump, void *bufferp)
172{
173 struct frame_unwind_cache *cache;
174
175 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
176 that the value proper does not need to be fetched. */
177 gdb_assert (optimizedp != NULL);
178 gdb_assert (lvalp != NULL);
179 gdb_assert (addrp != NULL);
180 gdb_assert (realnump != NULL);
181 /* gdb_assert (bufferp != NULL); */
182
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183 /* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame
184 is broken. There is always a frame. If there, for some reason,
185 isn't, there is some pretty busted code as it should have
186 detected the problem before calling here. */
187 gdb_assert (frame != NULL);
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188
189 /* Ask this frame to unwind its register. */
494cca16
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190 frame->unwind->reg (frame, &frame->unwind_cache, regnum,
191 optimizedp, lvalp, addrp, realnump, bufferp);
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192}
193
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194void
195frame_register (struct frame_info *frame, int regnum,
196 int *optimizedp, enum lval_type *lvalp,
197 CORE_ADDR *addrp, int *realnump, void *bufferp)
198{
199 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
200 that the value proper does not need to be fetched. */
201 gdb_assert (optimizedp != NULL);
202 gdb_assert (lvalp != NULL);
203 gdb_assert (addrp != NULL);
204 gdb_assert (realnump != NULL);
205 /* gdb_assert (bufferp != NULL); */
206
207 /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
208 of the register in the register cache. It should instead return
209 the REGNUM corresponding to that register. Translate the . */
210 if (GET_SAVED_REGISTER_P ())
211 {
212 GET_SAVED_REGISTER (bufferp, optimizedp, addrp, frame, regnum, lvalp);
213 /* Compute the REALNUM if the caller wants it. */
214 if (*lvalp == lval_register)
215 {
216 int regnum;
217 for (regnum = 0; regnum < NUM_REGS + NUM_PSEUDO_REGS; regnum++)
218 {
219 if (*addrp == register_offset_hack (current_gdbarch, regnum))
220 {
221 *realnump = regnum;
222 return;
223 }
224 }
225 internal_error (__FILE__, __LINE__,
226 "Failed to compute the register number corresponding"
227 " to 0x%s", paddr_d (*addrp));
228 }
229 *realnump = -1;
230 return;
231 }
232
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233 /* Obtain the register value by unwinding the register from the next
234 (more inner frame). */
235 gdb_assert (frame != NULL && frame->next != NULL);
236 frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
237 realnump, bufferp);
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238}
239
135c175f 240void
5b181d62 241frame_unwind_register (struct frame_info *frame, int regnum, void *buf)
135c175f
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242{
243 int optimized;
244 CORE_ADDR addr;
245 int realnum;
246 enum lval_type lval;
135c175f
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247 frame_register_unwind (frame, regnum, &optimized, &lval, &addr,
248 &realnum, buf);
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249}
250
251void
252frame_unwind_signed_register (struct frame_info *frame, int regnum,
253 LONGEST *val)
254{
255 void *buf = alloca (MAX_REGISTER_RAW_SIZE);
256 frame_unwind_register (frame, regnum, buf);
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257 (*val) = extract_signed_integer (buf, REGISTER_VIRTUAL_SIZE (regnum));
258}
259
260void
261frame_unwind_unsigned_register (struct frame_info *frame, int regnum,
262 ULONGEST *val)
263{
135c175f 264 void *buf = alloca (MAX_REGISTER_RAW_SIZE);
5b181d62 265 frame_unwind_register (frame, regnum, buf);
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266 (*val) = extract_unsigned_integer (buf, REGISTER_VIRTUAL_SIZE (regnum));
267}
4f460812 268
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269void
270frame_read_register (struct frame_info *frame, int regnum, void *buf)
271{
272 gdb_assert (frame != NULL && frame->next != NULL);
273 frame_unwind_register (frame->next, regnum, buf);
274}
275
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276void
277frame_read_unsigned_register (struct frame_info *frame, int regnum,
278 ULONGEST *val)
279{
280 /* NOTE: cagney/2002-10-31: There is a bit of dogma here - there is
281 always a frame. Both this, and the equivalent
282 frame_read_signed_register() function, can only be called with a
283 valid frame. If, for some reason, this function is called
284 without a frame then the problem isn't here, but rather in the
285 caller. It should of first created a frame and then passed that
286 in. */
287 /* NOTE: cagney/2002-10-31: As a side bar, keep in mind that the
288 ``current_frame'' should not be treated as a special case. While
289 ``get_next_frame (current_frame) == NULL'' currently holds, it
290 should, as far as possible, not be relied upon. In the future,
291 ``get_next_frame (current_frame)'' may instead simply return a
292 normal frame object that simply always gets register values from
293 the register cache. Consequently, frame code should try to avoid
294 tests like ``if get_next_frame() == NULL'' and instead just rely
295 on recursive frame calls (like the below code) when manipulating
296 a frame chain. */
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297 gdb_assert (frame != NULL && frame->next != NULL);
298 frame_unwind_unsigned_register (frame->next, regnum, val);
f908a0eb
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299}
300
301void
302frame_read_signed_register (struct frame_info *frame, int regnum,
303 LONGEST *val)
304{
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305 /* See note above in frame_read_unsigned_register(). */
306 gdb_assert (frame != NULL && frame->next != NULL);
307 frame_unwind_signed_register (frame->next, regnum, val);
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308}
309
18cde8d5 310static void
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311generic_unwind_get_saved_register (char *raw_buffer,
312 int *optimizedp,
313 CORE_ADDR *addrp,
314 struct frame_info *frame,
315 int regnum,
316 enum lval_type *lvalp)
317{
318 int optimizedx;
319 CORE_ADDR addrx;
320 int realnumx;
321 enum lval_type lvalx;
322
323 if (!target_has_registers)
324 error ("No registers.");
325
326 /* Keep things simple, ensure that all the pointers (except valuep)
327 are non NULL. */
328 if (optimizedp == NULL)
329 optimizedp = &optimizedx;
330 if (lvalp == NULL)
331 lvalp = &lvalx;
332 if (addrp == NULL)
333 addrp = &addrx;
334
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335 gdb_assert (frame != NULL && frame->next != NULL);
336 frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
337 &realnumx, raw_buffer);
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338}
339
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340void
341get_saved_register (char *raw_buffer,
342 int *optimized,
343 CORE_ADDR *addrp,
344 struct frame_info *frame,
345 int regnum,
346 enum lval_type *lval)
347{
a216a322
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348 if (GET_SAVED_REGISTER_P ())
349 {
350 GET_SAVED_REGISTER (raw_buffer, optimized, addrp, frame, regnum, lval);
351 return;
352 }
353 generic_unwind_get_saved_register (raw_buffer, optimized, addrp, frame,
354 regnum, lval);
d65fe839
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355}
356
cda5a58a 357/* frame_register_read ()
d65fe839 358
cda5a58a 359 Find and return the value of REGNUM for the specified stack frame.
d65fe839
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360 The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
361
cda5a58a 362 Returns 0 if the register value could not be found. */
d65fe839 363
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364int
365frame_register_read (struct frame_info *frame, int regnum, void *myaddr)
d65fe839 366{
a216a322
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367 int optimized;
368 enum lval_type lval;
369 CORE_ADDR addr;
370 int realnum;
371 frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
d65fe839 372
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373 /* FIXME: cagney/2002-05-15: This test, is just bogus.
374
375 It indicates that the target failed to supply a value for a
376 register because it was "not available" at this time. Problem
377 is, the target still has the register and so get saved_register()
378 may be returning a value saved on the stack. */
379
d65fe839 380 if (register_cached (regnum) < 0)
cda5a58a 381 return 0; /* register value not available */
d65fe839 382
a216a322 383 return !optimized;
d65fe839 384}
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385
386
387/* Map between a frame register number and its name. A frame register
388 space is a superset of the cooked register space --- it also
389 includes builtin registers. */
390
391int
392frame_map_name_to_regnum (const char *name, int len)
393{
394 int i;
395
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396 if (len < 0)
397 len = strlen (name);
398
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399 /* Search register name space. */
400 for (i = 0; i < NUM_REGS + NUM_PSEUDO_REGS; i++)
401 if (REGISTER_NAME (i) && len == strlen (REGISTER_NAME (i))
402 && strncmp (name, REGISTER_NAME (i), len) == 0)
403 {
404 return i;
405 }
406
407 /* Try builtin registers. */
408 i = builtin_reg_map_name_to_regnum (name, len);
409 if (i >= 0)
410 {
411 /* A builtin register doesn't fall into the architecture's
412 register range. */
413 gdb_assert (i >= NUM_REGS + NUM_PSEUDO_REGS);
414 return i;
415 }
416
417 return -1;
418}
419
420const char *
421frame_map_regnum_to_name (int regnum)
422{
423 if (regnum < 0)
424 return NULL;
425 if (regnum < NUM_REGS + NUM_PSEUDO_REGS)
426 return REGISTER_NAME (regnum);
427 return builtin_reg_map_regnum_to_name (regnum);
428}
4c1e7e9d 429
a94dd1fd
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430/* Create a sentinel frame. */
431
432struct frame_info *
433create_sentinel_frame (struct regcache *regcache)
434{
435 struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
436 frame->type = NORMAL_FRAME;
437 frame->level = -1;
438 /* Explicitly initialize the sentinel frame's cache. Provide it
439 with the underlying regcache. In the future additional
440 information, such as the frame's thread will be added. */
441 frame->unwind_cache = sentinel_frame_cache (regcache);
442 /* For the moment there is only one sentinel frame implementation. */
443 frame->unwind = sentinel_frame_unwind;
444 /* Link this frame back to itself. The frame is self referential
445 (the unwound PC is the same as the pc), so make it so. */
446 frame->next = frame;
447 /* Always unwind the PC as part of creating this frame. This
448 ensures that the frame's PC points at something valid. */
449 /* FIXME: cagney/2003-01-10: Problem here. Unwinding a sentinel
450 frame's PC may require information such as the frame's thread's
451 stop reason. Is it possible to get to that? */
452 frame->pc = frame_pc_unwind (frame);
453 return frame;
454}
455
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456/* Info about the innermost stack frame (contents of FP register) */
457
458static struct frame_info *current_frame;
459
460/* Cache for frame addresses already read by gdb. Valid only while
461 inferior is stopped. Control variables for the frame cache should
462 be local to this module. */
463
464static struct obstack frame_cache_obstack;
465
466void *
479ab5a0 467frame_obstack_zalloc (unsigned long size)
4c1e7e9d 468{
479ab5a0
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469 void *data = obstack_alloc (&frame_cache_obstack, size);
470 memset (data, 0, size);
471 return data;
4c1e7e9d
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472}
473
6baff1d2 474CORE_ADDR *
4c1e7e9d
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475frame_saved_regs_zalloc (struct frame_info *fi)
476{
477 fi->saved_regs = (CORE_ADDR *)
479ab5a0 478 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS);
6baff1d2 479 return fi->saved_regs;
4c1e7e9d
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480}
481
6baff1d2
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482CORE_ADDR *
483get_frame_saved_regs (struct frame_info *fi)
484{
485 return fi->saved_regs;
486}
4c1e7e9d 487
a94dd1fd
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488/* Return the innermost (currently executing) stack frame. This is
489 split into two functions. The function unwind_to_current_frame()
490 is wrapped in catch exceptions so that, even when the unwind of the
491 sentinel frame fails, the function still returns a stack frame. */
492
493static int
494unwind_to_current_frame (struct ui_out *ui_out, void *args)
495{
496 struct frame_info *frame = get_prev_frame (args);
497 /* A sentinel frame can fail to unwind, eg, because it's PC value
498 lands in somewhere like start. */
499 if (frame == NULL)
500 return 1;
501 current_frame = frame;
502 return 0;
503}
4c1e7e9d
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504
505struct frame_info *
506get_current_frame (void)
507{
a94dd1fd
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508 if (!target_has_stack)
509 error ("No stack.");
510 if (!target_has_registers)
511 error ("No registers.");
512 if (!target_has_memory)
513 error ("No memory.");
4c1e7e9d
AC
514 if (current_frame == NULL)
515 {
a94dd1fd
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516 struct frame_info *sentinel_frame =
517 create_sentinel_frame (current_regcache);
518 if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
519 NULL, RETURN_MASK_ERROR) != 0)
520 {
521 /* Oops! Fake a current frame? Is this useful? It has a PC
522 of zero, for instance. */
523 current_frame = sentinel_frame;
524 }
4c1e7e9d
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525 }
526 return current_frame;
527}
528
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529/* The "selected" stack frame is used by default for local and arg
530 access. May be zero, for no selected frame. */
531
532struct frame_info *deprecated_selected_frame;
533
534/* Return the selected frame. Always non-null (unless there isn't an
535 inferior sufficient for creating a frame) in which case an error is
536 thrown. */
537
538struct frame_info *
539get_selected_frame (void)
540{
541 if (deprecated_selected_frame == NULL)
542 /* Hey! Don't trust this. It should really be re-finding the
543 last selected frame of the currently selected thread. This,
544 though, is better than nothing. */
545 select_frame (get_current_frame ());
546 /* There is always a frame. */
547 gdb_assert (deprecated_selected_frame != NULL);
548 return deprecated_selected_frame;
549}
550
551/* Select frame FI (or NULL - to invalidate the current frame). */
552
553void
554select_frame (struct frame_info *fi)
555{
556 register struct symtab *s;
557
558 deprecated_selected_frame = fi;
559 /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
560 frame is being invalidated. */
561 if (selected_frame_level_changed_hook)
562 selected_frame_level_changed_hook (frame_relative_level (fi));
563
564 /* FIXME: kseitz/2002-08-28: It would be nice to call
565 selected_frame_level_changed_event right here, but due to limitations
566 in the current interfaces, we would end up flooding UIs with events
567 because select_frame is used extensively internally.
568
569 Once we have frame-parameterized frame (and frame-related) commands,
570 the event notification can be moved here, since this function will only
571 be called when the users selected frame is being changed. */
572
573 /* Ensure that symbols for this frame are read in. Also, determine the
574 source language of this frame, and switch to it if desired. */
575 if (fi)
576 {
577 s = find_pc_symtab (fi->pc);
578 if (s
579 && s->language != current_language->la_language
580 && s->language != language_unknown
581 && language_mode == language_mode_auto)
582 {
583 set_language (s->language);
584 }
585 }
586}
587
4c1e7e9d
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588/* Return the register saved in the simplistic ``saved_regs'' cache.
589 If the value isn't here AND a value is needed, try the next inner
590 most frame. */
591
592static void
593frame_saved_regs_register_unwind (struct frame_info *frame, void **cache,
594 int regnum, int *optimizedp,
595 enum lval_type *lvalp, CORE_ADDR *addrp,
596 int *realnump, void *bufferp)
597{
598 /* There is always a frame at this point. And THIS is the frame
599 we're interested in. */
600 gdb_assert (frame != NULL);
601 /* If we're using generic dummy frames, we'd better not be in a call
602 dummy. (generic_call_dummy_register_unwind ought to have been called
603 instead.) */
07555a72 604 gdb_assert (!(DEPRECATED_USE_GENERIC_DUMMY_FRAMES
5e0f933e 605 && (get_frame_type (frame) == DUMMY_FRAME)));
4c1e7e9d 606
8f871025
AC
607 /* Only (older) architectures that implement the
608 FRAME_INIT_SAVED_REGS method should be using this function. */
609 gdb_assert (FRAME_INIT_SAVED_REGS_P ());
610
4c1e7e9d 611 /* Load the saved_regs register cache. */
a94dd1fd 612 if (get_frame_saved_regs (frame) == NULL)
4c1e7e9d
AC
613 FRAME_INIT_SAVED_REGS (frame);
614
a94dd1fd
AC
615 if (get_frame_saved_regs (frame) != NULL
616 && get_frame_saved_regs (frame)[regnum] != 0)
4c1e7e9d
AC
617 {
618 if (regnum == SP_REGNUM)
619 {
620 /* SP register treated specially. */
621 *optimizedp = 0;
622 *lvalp = not_lval;
623 *addrp = 0;
624 *realnump = -1;
625 if (bufferp != NULL)
626 store_address (bufferp, REGISTER_RAW_SIZE (regnum),
a94dd1fd 627 get_frame_saved_regs (frame)[regnum]);
4c1e7e9d
AC
628 }
629 else
630 {
631 /* Any other register is saved in memory, fetch it but cache
632 a local copy of its value. */
633 *optimizedp = 0;
634 *lvalp = lval_memory;
a94dd1fd 635 *addrp = get_frame_saved_regs (frame)[regnum];
4c1e7e9d
AC
636 *realnump = -1;
637 if (bufferp != NULL)
638 {
639#if 1
640 /* Save each register value, as it is read in, in a
641 frame based cache. */
642 void **regs = (*cache);
643 if (regs == NULL)
644 {
645 int sizeof_cache = ((NUM_REGS + NUM_PSEUDO_REGS)
646 * sizeof (void *));
479ab5a0 647 regs = frame_obstack_zalloc (sizeof_cache);
4c1e7e9d
AC
648 (*cache) = regs;
649 }
650 if (regs[regnum] == NULL)
651 {
652 regs[regnum]
479ab5a0 653 = frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum));
a94dd1fd 654 read_memory (get_frame_saved_regs (frame)[regnum], regs[regnum],
4c1e7e9d
AC
655 REGISTER_RAW_SIZE (regnum));
656 }
657 memcpy (bufferp, regs[regnum], REGISTER_RAW_SIZE (regnum));
658#else
659 /* Read the value in from memory. */
a94dd1fd 660 read_memory (get_frame_saved_regs (frame)[regnum], bufferp,
4c1e7e9d
AC
661 REGISTER_RAW_SIZE (regnum));
662#endif
663 }
664 }
665 return;
666 }
667
668 /* No luck, assume this and the next frame have the same register
a94dd1fd
AC
669 value. Pass the request down the frame chain to the next frame.
670 Hopefully that will find the register's location, either in a
671 register or in memory. */
672 frame_register (frame, regnum, optimizedp, lvalp, addrp, realnump,
673 bufferp);
4c1e7e9d
AC
674}
675
f18c5a73
AC
676static CORE_ADDR
677frame_saved_regs_pc_unwind (struct frame_info *frame, void **cache)
678{
d62d1979 679 gdb_assert (FRAME_SAVED_PC_P ());
f18c5a73
AC
680 return FRAME_SAVED_PC (frame);
681}
682
c170fb60
AC
683static void
684frame_saved_regs_id_unwind (struct frame_info *next_frame, void **cache,
685 struct frame_id *id)
c689142b
AC
686{
687 int fromleaf;
c170fb60
AC
688 CORE_ADDR base;
689 CORE_ADDR pc;
690
691 /* Start out by assuming it's NULL. */
692 (*id) = null_frame_id;
c689142b 693
a94dd1fd 694 if (frame_relative_level (next_frame) <= 0)
c689142b
AC
695 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
696 the frame chain, not just the inner most frame! The generic,
697 per-architecture, frame code should handle this and the below
698 should simply be removed. */
699 fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame);
700 else
701 fromleaf = 0;
702
703 if (fromleaf)
704 /* A frameless inner-most frame. The `FP' (which isn't an
705 architecture frame-pointer register!) of the caller is the same
706 as the callee. */
707 /* FIXME: 2002-11-09: There isn't any reason to special case this
708 edge condition. Instead the per-architecture code should hande
709 it locally. */
c170fb60 710 base = get_frame_base (next_frame);
c689142b
AC
711 else
712 {
713 /* Two macros defined in tm.h specify the machine-dependent
714 actions to be performed here.
715
716 First, get the frame's chain-pointer.
717
718 If that is zero, the frame is the outermost frame or a leaf
719 called by the outermost frame. This means that if start
720 calls main without a frame, we'll return 0 (which is fine
721 anyway).
722
723 Nope; there's a problem. This also returns when the current
724 routine is a leaf of main. This is unacceptable. We move
725 this to after the ffi test; I'd rather have backtraces from
726 start go curfluy than have an abort called from main not show
727 main. */
d62d1979 728 gdb_assert (FRAME_CHAIN_P ());
c170fb60 729 base = FRAME_CHAIN (next_frame);
c689142b 730
c170fb60
AC
731 if (!frame_chain_valid (base, next_frame))
732 return;
c689142b 733 }
c170fb60
AC
734 if (base == 0)
735 return;
c689142b
AC
736
737 /* FIXME: cagney/2002-06-08: This should probably return the frame's
738 function and not the PC (a.k.a. resume address). */
c170fb60
AC
739 pc = frame_pc_unwind (next_frame);
740 id->pc = pc;
741 id->base = base;
c689142b
AC
742}
743
dbe9fe58
AC
744static void
745frame_saved_regs_pop (struct frame_info *fi, void **cache,
746 struct regcache *regcache)
747{
dedc2a2b 748 gdb_assert (POP_FRAME_P ());
dbe9fe58
AC
749 POP_FRAME;
750}
751
494cca16 752const struct frame_unwind trad_frame_unwinder = {
dbe9fe58 753 frame_saved_regs_pop,
494cca16
AC
754 frame_saved_regs_pc_unwind,
755 frame_saved_regs_id_unwind,
756 frame_saved_regs_register_unwind
757};
758const struct frame_unwind *trad_frame_unwind = &trad_frame_unwinder;
759
760
4c1e7e9d
AC
761/* Function: get_saved_register
762 Find register number REGNUM relative to FRAME and put its (raw,
763 target format) contents in *RAW_BUFFER.
764
765 Set *OPTIMIZED if the variable was optimized out (and thus can't be
766 fetched). Note that this is never set to anything other than zero
767 in this implementation.
768
769 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
770 whether the value was fetched from memory, from a register, or in a
771 strange and non-modifiable way (e.g. a frame pointer which was
772 calculated rather than fetched). We will use not_lval for values
773 fetched from generic dummy frames.
774
775 Set *ADDRP to the address, either in memory or as a REGISTER_BYTE
776 offset into the registers array. If the value is stored in a dummy
777 frame, set *ADDRP to zero.
778
779 To use this implementation, define a function called
780 "get_saved_register" in your target code, which simply passes all
781 of its arguments to this function.
782
783 The argument RAW_BUFFER must point to aligned memory. */
784
785void
786deprecated_generic_get_saved_register (char *raw_buffer, int *optimized,
787 CORE_ADDR *addrp,
788 struct frame_info *frame, int regnum,
789 enum lval_type *lval)
790{
791 if (!target_has_registers)
792 error ("No registers.");
793
8f871025
AC
794 gdb_assert (FRAME_INIT_SAVED_REGS_P ());
795
4c1e7e9d
AC
796 /* Normal systems don't optimize out things with register numbers. */
797 if (optimized != NULL)
798 *optimized = 0;
799
800 if (addrp) /* default assumption: not found in memory */
801 *addrp = 0;
802
803 /* Note: since the current frame's registers could only have been
804 saved by frames INTERIOR TO the current frame, we skip examining
805 the current frame itself: otherwise, we would be getting the
806 previous frame's registers which were saved by the current frame. */
807
a94dd1fd 808 if (frame != NULL)
4c1e7e9d 809 {
a94dd1fd
AC
810 for (frame = get_next_frame (frame);
811 frame_relative_level (frame) >= 0;
812 frame = get_next_frame (frame))
4c1e7e9d 813 {
a94dd1fd 814 if (get_frame_type (frame) == DUMMY_FRAME)
4c1e7e9d 815 {
a94dd1fd
AC
816 if (lval) /* found it in a CALL_DUMMY frame */
817 *lval = not_lval;
818 if (raw_buffer)
819 /* FIXME: cagney/2002-06-26: This should be via the
820 gdbarch_register_read() method so that it, on the
821 fly, constructs either a raw or pseudo register
822 from the raw register cache. */
823 regcache_raw_read
824 (generic_find_dummy_frame (get_frame_pc (frame),
825 get_frame_base (frame)),
826 regnum, raw_buffer);
827 return;
4c1e7e9d 828 }
a94dd1fd
AC
829
830 FRAME_INIT_SAVED_REGS (frame);
831 if (get_frame_saved_regs (frame) != NULL
832 && get_frame_saved_regs (frame)[regnum] != 0)
4c1e7e9d 833 {
a94dd1fd
AC
834 if (lval) /* found it saved on the stack */
835 *lval = lval_memory;
836 if (regnum == SP_REGNUM)
837 {
838 if (raw_buffer) /* SP register treated specially */
839 store_address (raw_buffer, REGISTER_RAW_SIZE (regnum),
840 get_frame_saved_regs (frame)[regnum]);
841 }
842 else
843 {
844 if (addrp) /* any other register */
845 *addrp = get_frame_saved_regs (frame)[regnum];
846 if (raw_buffer)
847 read_memory (get_frame_saved_regs (frame)[regnum], raw_buffer,
848 REGISTER_RAW_SIZE (regnum));
849 }
850 return;
4c1e7e9d 851 }
4c1e7e9d
AC
852 }
853 }
854
855 /* If we get thru the loop to this point, it means the register was
856 not saved in any frame. Return the actual live-register value. */
857
858 if (lval) /* found it in a live register */
859 *lval = lval_register;
860 if (addrp)
861 *addrp = REGISTER_BYTE (regnum);
862 if (raw_buffer)
863 deprecated_read_register_gen (regnum, raw_buffer);
864}
865
eb4f72c5
AC
866/* Determine the frame's type based on its PC. */
867
868static enum frame_type
869frame_type_from_pc (CORE_ADDR pc)
870{
871 /* FIXME: cagney/2002-11-24: Can't yet directly call
872 pc_in_dummy_frame() as some architectures don't set
873 PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the
874 latter is implemented by simply calling pc_in_dummy_frame). */
875 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
876 && DEPRECATED_PC_IN_CALL_DUMMY (pc, 0, 0))
877 return DUMMY_FRAME;
878 else
879 {
880 char *name;
881 find_pc_partial_function (pc, &name, NULL, NULL);
882 if (PC_IN_SIGTRAMP (pc, name))
883 return SIGTRAMP_FRAME;
884 else
885 return NORMAL_FRAME;
886 }
887}
888
4c1e7e9d
AC
889/* Create an arbitrary (i.e. address specified by user) or innermost frame.
890 Always returns a non-NULL value. */
891
892struct frame_info *
893create_new_frame (CORE_ADDR addr, CORE_ADDR pc)
894{
895 struct frame_info *fi;
4c1e7e9d 896
479ab5a0 897 fi = frame_obstack_zalloc (sizeof (struct frame_info));
4c1e7e9d
AC
898
899 fi->frame = addr;
900 fi->pc = pc;
a94dd1fd 901 fi->next = create_sentinel_frame (current_regcache);
eb4f72c5 902 fi->type = frame_type_from_pc (pc);
4c1e7e9d
AC
903
904 if (INIT_EXTRA_FRAME_INFO_P ())
905 INIT_EXTRA_FRAME_INFO (0, fi);
906
907 /* Select/initialize an unwind function. */
494cca16 908 fi->unwind = frame_unwind_find_by_pc (current_gdbarch, fi->pc);
4c1e7e9d
AC
909
910 return fi;
911}
912
913/* Return the frame that FRAME calls (NULL if FRAME is the innermost
a94dd1fd
AC
914 frame). Be careful to not fall off the bottom of the frame chain
915 and onto the sentinel frame. */
4c1e7e9d
AC
916
917struct frame_info *
918get_next_frame (struct frame_info *frame)
919{
a94dd1fd
AC
920 if (frame->level > 0)
921 return frame->next;
922 else
923 return NULL;
4c1e7e9d
AC
924}
925
926/* Flush the entire frame cache. */
927
928void
929flush_cached_frames (void)
930{
931 /* Since we can't really be sure what the first object allocated was */
932 obstack_free (&frame_cache_obstack, 0);
933 obstack_init (&frame_cache_obstack);
934
935 current_frame = NULL; /* Invalidate cache */
936 select_frame (NULL);
937 annotate_frames_invalid ();
938}
939
940/* Flush the frame cache, and start a new one if necessary. */
941
942void
943reinit_frame_cache (void)
944{
945 flush_cached_frames ();
946
947 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
948 if (PIDGET (inferior_ptid) != 0)
949 {
950 select_frame (get_current_frame ());
951 }
952}
953
eb4f72c5
AC
954/* Create the previous frame using the deprecated methods
955 INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */
4c1e7e9d 956
eb4f72c5
AC
957static struct frame_info *
958legacy_get_prev_frame (struct frame_info *next_frame)
4c1e7e9d
AC
959{
960 CORE_ADDR address = 0;
961 struct frame_info *prev;
95adb866 962 int fromleaf;
4c1e7e9d 963
eb4f72c5
AC
964 /* This code only works on normal frames. A sentinel frame, where
965 the level is -1, should never reach this code. */
966 gdb_assert (next_frame->level >= 0);
4c1e7e9d
AC
967
968 /* On some machines it is possible to call a function without
969 setting up a stack frame for it. On these machines, we
970 define this macro to take two args; a frameinfo pointer
971 identifying a frame and a variable to set or clear if it is
972 or isn't leafless. */
973
974 /* Still don't want to worry about this except on the innermost
95adb866
AC
975 frame. This macro will set FROMLEAF if NEXT_FRAME is a frameless
976 function invocation. */
eb4f72c5 977 if (next_frame->level == 0)
95adb866
AC
978 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
979 the frame chain, not just the inner most frame! The generic,
980 per-architecture, frame code should handle this and the below
981 should simply be removed. */
982 fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame);
983 else
984 fromleaf = 0;
985
986 if (fromleaf)
987 /* A frameless inner-most frame. The `FP' (which isn't an
988 architecture frame-pointer register!) of the caller is the same
989 as the callee. */
990 /* FIXME: 2002-11-09: There isn't any reason to special case this
991 edge condition. Instead the per-architecture code should hande
992 it locally. */
c193f6ac 993 address = get_frame_base (next_frame);
95adb866 994 else
4c1e7e9d
AC
995 {
996 /* Two macros defined in tm.h specify the machine-dependent
997 actions to be performed here.
95adb866 998
4c1e7e9d 999 First, get the frame's chain-pointer.
95adb866 1000
4c1e7e9d
AC
1001 If that is zero, the frame is the outermost frame or a leaf
1002 called by the outermost frame. This means that if start
1003 calls main without a frame, we'll return 0 (which is fine
1004 anyway).
1005
1006 Nope; there's a problem. This also returns when the current
1007 routine is a leaf of main. This is unacceptable. We move
1008 this to after the ffi test; I'd rather have backtraces from
1009 start go curfluy than have an abort called from main not show
1010 main. */
d62d1979 1011 gdb_assert (FRAME_CHAIN_P ());
4c1e7e9d
AC
1012 address = FRAME_CHAIN (next_frame);
1013
51603483 1014 if (!frame_chain_valid (address, next_frame))
4c1e7e9d
AC
1015 return 0;
1016 }
1017 if (address == 0)
1018 return 0;
1019
95adb866 1020 /* Create an initially zero previous frame. */
479ab5a0 1021 prev = frame_obstack_zalloc (sizeof (struct frame_info));
4c1e7e9d 1022
95adb866
AC
1023 /* Link it in. */
1024 next_frame->prev = prev;
4c1e7e9d
AC
1025 prev->next = next_frame;
1026 prev->frame = address;
1027 prev->level = next_frame->level + 1;
5a203e44
AC
1028 /* FIXME: cagney/2002-11-18: Should be setting the frame's type
1029 here, before anything else, and not last. Various INIT functions
1030 are full of work-arounds for the frames type not being set
1031 correctly from the word go. Ulgh! */
1032 prev->type = NORMAL_FRAME;
4c1e7e9d 1033
95adb866 1034 /* This change should not be needed, FIXME! We should determine
a5afb99f
AC
1035 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1036 after INIT_EXTRA_FRAME_INFO and come up with a simple way to
1037 express what goes on here.
95adb866
AC
1038
1039 INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame
1040 (where the PC is already set up) and here (where it isn't).
a5afb99f 1041 DEPRECATED_INIT_FRAME_PC is only called from here, always after
95adb866
AC
1042 INIT_EXTRA_FRAME_INFO.
1043
1044 The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the
1045 PC value (which hasn't been set yet). Some other machines appear
1046 to require INIT_EXTRA_FRAME_INFO before they can do
a5afb99f 1047 DEPRECATED_INIT_FRAME_PC. Phoo.
95adb866 1048
2ca6c561
AC
1049 We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
1050 complication to an already overcomplicated part of GDB.
1051 gnu@cygnus.com, 15Sep92.
95adb866 1052
a5afb99f 1053 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
95adb866
AC
1054 INIT_EXTRA_FRAME_INFO, one possible scheme:
1055
1056 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1057 (read_fp ()), read_pc ()). Machines with extra frame info would
1058 do that (or the local equivalent) and then set the extra fields.
1059
1060 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1061 create_new_frame would no longer init extra frame info;
1062 SETUP_ARBITRARY_FRAME would have to do that.
1063
1064 INIT_PREV_FRAME(fromleaf, prev) Replace INIT_EXTRA_FRAME_INFO and
a5afb99f
AC
1065 DEPRECATED_INIT_FRAME_PC. This should also return a flag saying
1066 whether to keep the new frame, or whether to discard it, because
1067 on some machines (e.g. mips) it is really awkward to have
95adb866
AC
1068 FRAME_CHAIN_VALID called *before* INIT_EXTRA_FRAME_INFO (there is
1069 no good way to get information deduced in FRAME_CHAIN_VALID into
1070 the extra fields of the new frame). std_frame_pc(fromleaf, prev)
1071
1072 This is the default setting for INIT_PREV_FRAME. It just does
a5afb99f
AC
1073 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1074 will call it from INIT_PREV_FRAME (either at the beginning, the
1075 end, or in the middle). Some machines won't use it.
95adb866
AC
1076
1077 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1078
1079 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1080 reason for things to be this complicated.
1081
1082 The trick is to assume that there is always a frame. Instead of
1083 special casing the inner-most frame, create fake frame
1084 (containing the hardware registers) that is inner to the
1085 user-visible inner-most frame (...) and then unwind from that.
1086 That way architecture code can use use the standard
1087 frame_XX_unwind() functions and not differentiate between the
1088 inner most and any other case.
1089
1090 Since there is always a frame to unwind from, there is always
1091 somewhere (NEXT_FRAME) to store all the info needed to construct
1092 a new (previous) frame without having to first create it. This
1093 means that the convolution below - needing to carefully order a
1094 frame's initialization - isn't needed.
1095
1096 The irony here though, is that FRAME_CHAIN(), at least for a more
1097 up-to-date architecture, always calls FRAME_SAVED_PC(), and
1098 FRAME_SAVED_PC() computes the PC but without first needing the
1099 frame! Instead of the convolution below, we could have simply
1100 called FRAME_SAVED_PC() and been done with it! Note that
1101 FRAME_SAVED_PC() is being superseed by frame_pc_unwind() and that
1102 function does have somewhere to cache that PC value. */
4c1e7e9d 1103
2ca6c561 1104 if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
97f46953 1105 prev->pc = (DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf, prev));
4c1e7e9d
AC
1106
1107 if (INIT_EXTRA_FRAME_INFO_P ())
1108 INIT_EXTRA_FRAME_INFO (fromleaf, prev);
1109
1110 /* This entry is in the frame queue now, which is good since
95adb866
AC
1111 FRAME_SAVED_PC may use that queue to figure out its value (see
1112 tm-sparc.h). We want the pc saved in the inferior frame. */
a5afb99f
AC
1113 if (DEPRECATED_INIT_FRAME_PC_P ())
1114 prev->pc = DEPRECATED_INIT_FRAME_PC (fromleaf, prev);
4c1e7e9d 1115
95adb866
AC
1116 /* If ->frame and ->pc are unchanged, we are in the process of
1117 getting ourselves into an infinite backtrace. Some architectures
1118 check this in FRAME_CHAIN or thereabouts, but it seems like there
1119 is no reason this can't be an architecture-independent check. */
1120 if (prev->frame == next_frame->frame
1121 && prev->pc == next_frame->pc)
4c1e7e9d 1122 {
95adb866
AC
1123 next_frame->prev = NULL;
1124 obstack_free (&frame_cache_obstack, prev);
1125 return NULL;
4c1e7e9d
AC
1126 }
1127
1128 /* Initialize the code used to unwind the frame PREV based on the PC
1129 (and probably other architectural information). The PC lets you
1130 check things like the debug info at that point (dwarf2cfi?) and
1131 use that to decide how the frame should be unwound. */
494cca16 1132 prev->unwind = frame_unwind_find_by_pc (current_gdbarch, prev->pc);
4c1e7e9d 1133
5a203e44
AC
1134 /* NOTE: cagney/2002-11-18: The code segments, found in
1135 create_new_frame and get_prev_frame(), that initializes the
1136 frames type is subtly different. The latter only updates ->type
1137 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1138 get_prev_frame() overriding the frame's type when the INIT code
1139 has previously set it. This is really somewhat bogus. The
1140 initialization, as seen in create_new_frame(), should occur
1141 before the INIT function has been called. */
07555a72 1142 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
ae45cd16
AC
1143 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
1144 ? DEPRECATED_PC_IN_CALL_DUMMY (prev->pc, 0, 0)
1145 : pc_in_dummy_frame (prev->pc)))
5a203e44
AC
1146 prev->type = DUMMY_FRAME;
1147 else
1148 {
1149 /* FIXME: cagney/2002-11-10: This should be moved to before the
1150 INIT code above so that the INIT code knows what the frame's
1151 type is (in fact, for a [generic] dummy-frame, the type can
1152 be set and then the entire initialization can be skipped.
1153 Unforunatly, its the INIT code that sets the PC (Hmm, catch
1154 22). */
1155 char *name;
1156 find_pc_partial_function (prev->pc, &name, NULL, NULL);
1157 if (PC_IN_SIGTRAMP (prev->pc, name))
1158 prev->type = SIGTRAMP_FRAME;
1159 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1160 architectures are forcing the frame's type in INIT so we
1161 don't want to override it here. Remember, NORMAL_FRAME == 0,
1162 so it all works (just :-/). Once this initialization is
1163 moved to the start of this function, all this nastness will
1164 go away. */
1165 }
4c1e7e9d
AC
1166
1167 return prev;
1168}
1169
eb4f72c5
AC
1170/* Return a structure containing various interesting information
1171 about the frame that called NEXT_FRAME. Returns NULL
1172 if there is no such frame. */
1173
1174struct frame_info *
1175get_prev_frame (struct frame_info *next_frame)
1176{
1177 struct frame_info *prev_frame;
1178
1179 /* Return the inner-most frame, when the caller passes in NULL. */
1180 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
1181 caller should have previously obtained a valid frame using
1182 get_selected_frame() and then called this code - only possibility
1183 I can think of is code behaving badly.
1184
1185 NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
1186 block_innermost_frame(). It does the sequence: frame = NULL;
1187 while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
1188 it couldn't be written better, I don't know.
1189
1190 NOTE: cagney/2003-01-11: I suspect what is happening is
1191 block_innermost_frame() is, when the target has no state
1192 (registers, memory, ...), still calling this function. The
1193 assumption being that this function will return NULL indicating
1194 that a frame isn't possible, rather than checking that the target
1195 has state and then calling get_current_frame() and
1196 get_prev_frame(). This is a guess mind. */
1197 if (next_frame == NULL)
1198 {
1199 /* NOTE: cagney/2002-11-09: There was a code segment here that
1200 would error out when CURRENT_FRAME was NULL. The comment
1201 that went with it made the claim ...
1202
1203 ``This screws value_of_variable, which just wants a nice
1204 clean NULL return from block_innermost_frame if there are no
1205 frames. I don't think I've ever seen this message happen
1206 otherwise. And returning NULL here is a perfectly legitimate
1207 thing to do.''
1208
1209 Per the above, this code shouldn't even be called with a NULL
1210 NEXT_FRAME. */
1211 return current_frame;
1212 }
1213
1214 /* There is always a frame. If this assertion fails, suspect that
1215 something should be calling get_selected_frame() or
1216 get_current_frame(). */
1217 gdb_assert (next_frame != NULL);
1218
1219 if (next_frame->level >= 0
1220 && !backtrace_below_main
1221 && inside_main_func (get_frame_pc (next_frame)))
1222 /* Don't unwind past main(), bug always unwind the sentinel frame.
1223 Note, this is done _before_ the frame has been marked as
1224 previously unwound. That way if the user later decides to
1225 allow unwinds past main(), that just happens. */
1226 return NULL;
1227
1228 /* Only try to do the unwind once. */
1229 if (next_frame->prev_p)
1230 return next_frame->prev;
1231 next_frame->prev_p = 1;
1232
1233 /* If we're inside the entry file, it isn't valid. */
1234 /* NOTE: drow/2002-12-25: should there be a way to disable this
1235 check? It assumes a single small entry file, and the way some
1236 debug readers (e.g. dbxread) figure out which object is the
1237 entry file is somewhat hokey. */
1238 /* NOTE: cagney/2003-01-10: If there is a way of disabling this test
1239 then it should probably be moved to before the ->prev_p test,
1240 above. */
1241 if (inside_entry_file (get_frame_pc (next_frame)))
1242 return NULL;
1243
1244 /* If any of the old frame initialization methods are around, use
1245 the legacy get_prev_frame method. Just don't try to unwind a
1246 sentinel frame using that method - it doesn't work. All sentinal
1247 frames use the new unwind code. */
1248 if ((DEPRECATED_INIT_FRAME_PC_P ()
1249 || DEPRECATED_INIT_FRAME_PC_FIRST_P ()
d62d1979
AC
1250 || INIT_EXTRA_FRAME_INFO_P ()
1251 || FRAME_CHAIN_P ())
eb4f72c5
AC
1252 && next_frame->level >= 0)
1253 return legacy_get_prev_frame (next_frame);
1254
1255 /* Allocate the new frame but do not wire it in to the frame chain.
1256 Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
1257 frame->next to pull some fancy tricks (of course such code is, by
1258 definition, recursive). Try to prevent it.
1259
1260 There is no reason to worry about memory leaks, should the
1261 remainder of the function fail. The allocated memory will be
1262 quickly reclaimed when the frame cache is flushed, and the `we've
1263 been here before' check above will stop repeated memory
1264 allocation calls. */
1265 prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
1266 prev_frame->level = next_frame->level + 1;
1267
1268 /* Try to unwind the PC. If that doesn't work, assume we've reached
1269 the oldest frame and simply return. Is there a better sentinal
1270 value? The unwound PC value is then used to initialize the new
1271 previous frame's type.
1272
1273 Note that the pc-unwind is intentionally performed before the
1274 frame chain. This is ok since, for old targets, both
1275 frame_pc_unwind (nee, FRAME_SAVED_PC) and FRAME_CHAIN()) assume
1276 NEXT_FRAME's data structures have already been initialized (using
1277 INIT_EXTRA_FRAME_INFO) and hence the call order doesn't matter.
1278
1279 By unwinding the PC first, it becomes possible to, in the case of
1280 a dummy frame, avoid also unwinding the frame ID. This is
1281 because (well ignoring the PPC) a dummy frame can be located
1282 using NEXT_FRAME's frame ID. */
1283
1284 prev_frame->pc = frame_pc_unwind (next_frame);
1285 if (prev_frame->pc == 0)
1286 /* The allocated PREV_FRAME will be reclaimed when the frame
1287 obstack is next purged. */
1288 return NULL;
1289 prev_frame->type = frame_type_from_pc (prev_frame->pc);
1290
1291 /* Set the unwind functions based on that identified PC. */
1292 prev_frame->unwind = frame_unwind_find_by_pc (current_gdbarch,
1293 prev_frame->pc);
1294
1295 /* FIXME: cagney/2003-01-13: A dummy frame doesn't need to unwind
1296 the frame ID because the frame ID comes from the previous frame.
1297 The other frames do though. True? */
1298 {
1299 /* FIXME: cagney/2002-12-18: Instead of this hack, should just
1300 save the frame ID directly. */
1301 struct frame_id id = frame_id_unwind (next_frame);
1302 if (!frame_id_p (id))
1303 return NULL;
1304 prev_frame->frame = id.base;
1305 }
1306
1307 /* Link it in. */
1308 next_frame->prev = prev_frame;
1309 prev_frame->next = next_frame;
1310
1311 /* FIXME: cagney/2002-01-19: This call will go away. Instead of
1312 initializing extra info, all frames will use the frame_cache
1313 (passed to the unwind functions) to store additional frame info.
1314 Unfortunatly legacy targets can't use legacy_get_prev_frame() to
1315 unwind the sentinel frame and, consequently, are forced to take
1316 this code path and rely on the below call to INIT_EXTR_FRAME_INFO
1317 to initialize the inner-most frame. */
1318 if (INIT_EXTRA_FRAME_INFO_P ())
1319 {
1320 gdb_assert (prev_frame->level == 0);
1321 INIT_EXTRA_FRAME_INFO (0, prev_frame);
1322 }
1323
1324 return prev_frame;
1325}
1326
4c1e7e9d
AC
1327CORE_ADDR
1328get_frame_pc (struct frame_info *frame)
1329{
1330 return frame->pc;
1331}
1332
1058bca7
AC
1333static int
1334pc_notcurrent (struct frame_info *frame)
1335{
1336 /* If FRAME is not the innermost frame, that normally means that
1337 FRAME->pc points at the return instruction (which is *after* the
1338 call instruction), and we want to get the line containing the
1339 call (because the call is where the user thinks the program is).
1340 However, if the next frame is either a SIGTRAMP_FRAME or a
1341 DUMMY_FRAME, then the next frame will contain a saved interrupt
1342 PC and such a PC indicates the current (rather than next)
1343 instruction/line, consequently, for such cases, want to get the
1344 line containing fi->pc. */
1345 struct frame_info *next = get_next_frame (frame);
1346 int notcurrent = (next != NULL && get_frame_type (next) == NORMAL_FRAME);
1347 return notcurrent;
1348}
1349
1350void
1351find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal)
1352{
1353 (*sal) = find_pc_line (frame->pc, pc_notcurrent (frame));
1354}
1355
c193f6ac
AC
1356/* Per "frame.h", return the ``address'' of the frame. Code should
1357 really be using get_frame_id(). */
1358CORE_ADDR
1359get_frame_base (struct frame_info *fi)
1360{
1361 return fi->frame;
1362}
1363
85cf597a
AC
1364/* Level of the selected frame: 0 for innermost, 1 for its caller, ...
1365 or -1 for a NULL frame. */
1366
1367int
1368frame_relative_level (struct frame_info *fi)
1369{
1370 if (fi == NULL)
1371 return -1;
1372 else
1373 return fi->level;
1374}
1375
5a203e44
AC
1376enum frame_type
1377get_frame_type (struct frame_info *frame)
1378{
1379 /* Some targets still don't use [generic] dummy frames. Catch them
1380 here. */
07555a72 1381 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
5a203e44
AC
1382 && deprecated_frame_in_dummy (frame))
1383 return DUMMY_FRAME;
1384 return frame->type;
1385}
1386
1387void
1388deprecated_set_frame_type (struct frame_info *frame, enum frame_type type)
1389{
1390 /* Arrrg! See comment in "frame.h". */
1391 frame->type = type;
1392}
1393
4c1e7e9d
AC
1394#ifdef FRAME_FIND_SAVED_REGS
1395/* XXX - deprecated. This is a compatibility function for targets
1396 that do not yet implement FRAME_INIT_SAVED_REGS. */
1397/* Find the addresses in which registers are saved in FRAME. */
1398
1399void
95486978
AC
1400deprecated_get_frame_saved_regs (struct frame_info *frame,
1401 struct frame_saved_regs *saved_regs_addr)
4c1e7e9d
AC
1402{
1403 if (frame->saved_regs == NULL)
1404 {
1405 frame->saved_regs = (CORE_ADDR *)
479ab5a0 1406 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS);
4c1e7e9d
AC
1407 }
1408 if (saved_regs_addr == NULL)
1409 {
1410 struct frame_saved_regs saved_regs;
1411 FRAME_FIND_SAVED_REGS (frame, saved_regs);
1412 memcpy (frame->saved_regs, &saved_regs, SIZEOF_FRAME_SAVED_REGS);
1413 }
1414 else
1415 {
1416 FRAME_FIND_SAVED_REGS (frame, *saved_regs_addr);
1417 memcpy (frame->saved_regs, saved_regs_addr, SIZEOF_FRAME_SAVED_REGS);
1418 }
1419}
1420#endif
1421
0394eb2a
AC
1422struct frame_extra_info *
1423get_frame_extra_info (struct frame_info *fi)
1424{
1425 return fi->extra_info;
1426}
1427
2c517d0e
AC
1428struct frame_extra_info *
1429frame_extra_info_zalloc (struct frame_info *fi, long size)
1430{
479ab5a0 1431 fi->extra_info = frame_obstack_zalloc (size);
2c517d0e
AC
1432 return fi->extra_info;
1433}
1434
b87efeee 1435void
2f107107 1436deprecated_update_frame_pc_hack (struct frame_info *frame, CORE_ADDR pc)
b87efeee 1437{
2f107107 1438 /* See comment in "frame.h". */
a94dd1fd 1439 gdb_assert (frame->next != NULL);
2f107107
AC
1440 frame->pc = pc;
1441}
1442
1443void
1444deprecated_update_frame_base_hack (struct frame_info *frame, CORE_ADDR base)
1445{
1446 /* See comment in "frame.h". */
1447 frame->frame = base;
b87efeee
AC
1448}
1449
c8b8a898
AC
1450void
1451deprecated_set_frame_saved_regs_hack (struct frame_info *frame,
1452 CORE_ADDR *saved_regs)
1453{
1454 frame->saved_regs = saved_regs;
1455}
1456
1457void
1458deprecated_set_frame_extra_info_hack (struct frame_info *frame,
1459 struct frame_extra_info *extra_info)
1460{
1461 frame->extra_info = extra_info;
1462}
1463
483d36b2
AC
1464void
1465deprecated_set_frame_next_hack (struct frame_info *fi,
1466 struct frame_info *next)
1467{
1468 fi->next = next;
1469}
1470
1471void
1472deprecated_set_frame_prev_hack (struct frame_info *fi,
1473 struct frame_info *prev)
1474{
1475 fi->prev = prev;
1476}
1477
2d75187b
AC
1478struct context *
1479deprecated_get_frame_context (struct frame_info *fi)
1480{
1481 return fi->context;
1482}
1483
1484void
1485deprecated_set_frame_context (struct frame_info *fi,
1486 struct context *context)
1487{
1488 fi->context = context;
1489}
1490
c8b8a898
AC
1491struct frame_info *
1492deprecated_frame_xmalloc (void)
1493{
1494 struct frame_info *frame = XMALLOC (struct frame_info);
1495 memset (frame, 0, sizeof (struct frame_info));
1496 return frame;
1497}
1498
f6c609c4
AC
1499struct frame_info *
1500deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs,
1501 long sizeof_extra_info)
1502{
1503 struct frame_info *frame = deprecated_frame_xmalloc ();
1504 make_cleanup (xfree, frame);
1505 if (sizeof_saved_regs > 0)
1506 {
1507 frame->saved_regs = xcalloc (1, sizeof_saved_regs);
1508 make_cleanup (xfree, frame->saved_regs);
1509 }
1510 if (sizeof_extra_info > 0)
1511 {
1512 frame->extra_info = xcalloc (1, sizeof_extra_info);
1513 make_cleanup (xfree, frame->extra_info);
1514 }
1515 return frame;
1516}
c8b8a898 1517
4c1e7e9d
AC
1518void
1519_initialize_frame (void)
1520{
1521 obstack_init (&frame_cache_obstack);
eb4f72c5
AC
1522
1523 /* FIXME: cagney/2003-01-19: This command needs a rename. Suggest
1524 `set backtrace {past,beyond,...}-main'. Also suggest adding `set
1525 backtrace ...-start' to control backtraces past start. The
1526 problem with `below' is that it stops the `up' command. */
1527
1528 add_setshow_boolean_cmd ("backtrace-below-main", class_obscure,
1529 &backtrace_below_main, "\
1530Set whether backtraces should continue past \"main\".\n\
1531Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
1532the backtrace at \"main\". Set this variable if you need to see the rest\n\
1533of the stack trace.", "\
1534Show whether backtraces should continue past \"main\".\n\
1535Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
1536the backtrace at \"main\". Set this variable if you need to see the rest\n\
1537of the stack trace.",
1538 NULL, NULL, &setlist, &showlist);
4c1e7e9d 1539}
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