1 /* Cache and manage frames for GDB, the GNU debugger.
3 Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000,
4 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
27 #include "inferior.h" /* for inferior_ptid */
29 #include "gdb_assert.h"
30 #include "gdb_string.h"
31 #include "user-regs.h"
32 #include "gdb_obstack.h"
33 #include "dummy-frame.h"
34 #include "sentinel-frame.h"
38 #include "frame-unwind.h"
39 #include "frame-base.h"
44 static struct frame_info *get_prev_frame_1 (struct frame_info *this_frame);
46 /* We keep a cache of stack frames, each of which is a "struct
47 frame_info". The innermost one gets allocated (in
48 wait_for_inferior) each time the inferior stops; current_frame
49 points to it. Additional frames get allocated (in get_prev_frame)
50 as needed, and are chained through the next and prev fields. Any
51 time that the frame cache becomes invalid (most notably when we
52 execute something, but also if we change how we interpret the
53 frames (e.g. "set heuristic-fence-post" in mips-tdep.c, or anything
54 which reads new symbols)), we should call reinit_frame_cache. */
58 /* Level of this frame. The inner-most (youngest) frame is at level
59 0. As you move towards the outer-most (oldest) frame, the level
60 increases. This is a cached value. It could just as easily be
61 computed by counting back from the selected frame to the inner
63 /* NOTE: cagney/2002-04-05: Perhaps a level of ``-1'' should be
64 reserved to indicate a bogus frame - one that has been created
65 just to keep GDB happy (GDB always needs a frame). For the
66 moment leave this as speculation. */
69 /* The frame's type. */
70 /* FIXME: cagney/2003-04-02: Should instead be returning
71 ->unwind->type. Unfortunately, legacy code is still explicitly
72 setting the type using the method deprecated_set_frame_type.
73 Eliminate that method and this field can be eliminated. */
76 /* For each register, address of where it was saved on entry to the
77 frame, or zero if it was not saved on entry to this frame. This
78 includes special registers such as pc and fp saved in special
79 ways in the stack frame. The SP_REGNUM is even more special, the
80 address here is the sp for the previous frame, not the address
81 where the sp was saved. */
82 /* Allocated by frame_saved_regs_zalloc () which is called /
83 initialized by DEPRECATED_FRAME_INIT_SAVED_REGS(). */
84 CORE_ADDR *saved_regs; /*NUM_REGS + NUM_PSEUDO_REGS*/
86 /* Anything extra for this structure that may have been defined in
87 the machine dependent files. */
88 /* Allocated by frame_extra_info_zalloc () which is called /
89 initialized by DEPRECATED_INIT_EXTRA_FRAME_INFO */
90 struct frame_extra_info *extra_info;
92 /* The frame's low-level unwinder and corresponding cache. The
93 low-level unwinder is responsible for unwinding register values
94 for the previous frame. The low-level unwind methods are
95 selected based on the presence, or otherwise, of register unwind
96 information such as CFI. */
98 const struct frame_unwind *unwind;
100 /* Cached copy of the previous frame's resume address. */
106 /* Cached copy of the previous frame's function address. */
113 /* This frame's ID. */
117 struct frame_id value;
120 /* The frame's high-level base methods, and corresponding cache.
121 The high level base methods are selected based on the frame's
123 const struct frame_base *base;
126 /* Pointers to the next (down, inner, younger) and previous (up,
127 outer, older) frame_info's in the frame cache. */
128 struct frame_info *next; /* down, inner, younger */
130 struct frame_info *prev; /* up, outer, older */
133 /* Flag to control debugging. */
135 static int frame_debug;
137 /* Flag to indicate whether backtraces should stop at main et.al. */
139 static int backtrace_past_main;
140 static unsigned int backtrace_limit = UINT_MAX;
144 fprint_frame_id (struct ui_file *file, struct frame_id id)
146 fprintf_unfiltered (file, "{stack=0x%s,code=0x%s,special=0x%s}",
147 paddr_nz (id.stack_addr),
148 paddr_nz (id.code_addr),
149 paddr_nz (id.special_addr));
153 fprint_frame_type (struct ui_file *file, enum frame_type type)
158 fprintf_unfiltered (file, "UNKNOWN_FRAME");
161 fprintf_unfiltered (file, "NORMAL_FRAME");
164 fprintf_unfiltered (file, "DUMMY_FRAME");
167 fprintf_unfiltered (file, "SIGTRAMP_FRAME");
170 fprintf_unfiltered (file, "<unknown type>");
176 fprint_frame (struct ui_file *file, struct frame_info *fi)
180 fprintf_unfiltered (file, "<NULL frame>");
183 fprintf_unfiltered (file, "{");
184 fprintf_unfiltered (file, "level=%d", fi->level);
185 fprintf_unfiltered (file, ",");
186 fprintf_unfiltered (file, "type=");
187 fprint_frame_type (file, fi->type);
188 fprintf_unfiltered (file, ",");
189 fprintf_unfiltered (file, "unwind=");
190 if (fi->unwind != NULL)
191 gdb_print_host_address (fi->unwind, file);
193 fprintf_unfiltered (file, "<unknown>");
194 fprintf_unfiltered (file, ",");
195 fprintf_unfiltered (file, "pc=");
196 if (fi->next != NULL && fi->next->prev_pc.p)
197 fprintf_unfiltered (file, "0x%s", paddr_nz (fi->next->prev_pc.value));
199 fprintf_unfiltered (file, "<unknown>");
200 fprintf_unfiltered (file, ",");
201 fprintf_unfiltered (file, "id=");
203 fprint_frame_id (file, fi->this_id.value);
205 fprintf_unfiltered (file, "<unknown>");
206 fprintf_unfiltered (file, ",");
207 fprintf_unfiltered (file, "func=");
208 if (fi->next != NULL && fi->next->prev_func.p)
209 fprintf_unfiltered (file, "0x%s", paddr_nz (fi->next->prev_func.addr));
211 fprintf_unfiltered (file, "<unknown>");
212 fprintf_unfiltered (file, "}");
215 /* Return a frame uniq ID that can be used to, later, re-find the
219 get_frame_id (struct frame_info *fi)
223 return null_frame_id;
227 gdb_assert (!legacy_frame_p (current_gdbarch));
229 fprintf_unfiltered (gdb_stdlog, "{ get_frame_id (fi=%d) ",
231 /* Find the unwinder. */
232 if (fi->unwind == NULL)
234 fi->unwind = frame_unwind_find_by_frame (fi->next,
235 &fi->prologue_cache);
236 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
237 type in the frame, the unwinder's type should be returned
238 directly. Unfortunately legacy code, called by
239 legacy_get_prev_frame(), explicitly sets the frame's type
240 using the method deprecated_set_frame_type(). */
241 fi->type = fi->unwind->type;
243 /* Find THIS frame's ID. */
244 fi->unwind->this_id (fi->next, &fi->prologue_cache, &fi->this_id.value);
248 fprintf_unfiltered (gdb_stdlog, "-> ");
249 fprint_frame_id (gdb_stdlog, fi->this_id.value);
250 fprintf_unfiltered (gdb_stdlog, " }\n");
253 return fi->this_id.value;
257 frame_unwind_id (struct frame_info *next_frame)
259 /* Use prev_frame, and not get_prev_frame. The latter will truncate
260 the frame chain, leading to this function unintentionally
261 returning a null_frame_id (e.g., when a caller requests the frame
262 ID of "main()"s caller. */
263 return get_frame_id (get_prev_frame_1 (next_frame));
266 const struct frame_id null_frame_id; /* All zeros. */
269 frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr,
270 CORE_ADDR special_addr)
273 id.stack_addr = stack_addr;
274 id.code_addr = code_addr;
275 id.special_addr = special_addr;
280 frame_id_build (CORE_ADDR stack_addr, CORE_ADDR code_addr)
282 return frame_id_build_special (stack_addr, code_addr, 0);
286 frame_id_p (struct frame_id l)
289 /* The .code can be NULL but the .stack cannot. */
290 p = (l.stack_addr != 0);
293 fprintf_unfiltered (gdb_stdlog, "{ frame_id_p (l=");
294 fprint_frame_id (gdb_stdlog, l);
295 fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", p);
301 frame_id_eq (struct frame_id l, struct frame_id r)
304 if (l.stack_addr == 0 || r.stack_addr == 0)
305 /* Like a NaN, if either ID is invalid, the result is false. */
307 else if (l.stack_addr != r.stack_addr)
308 /* If .stack addresses are different, the frames are different. */
310 else if (l.code_addr == 0 || r.code_addr == 0)
311 /* A zero code addr is a wild card, always succeed. */
313 else if (l.code_addr != r.code_addr)
314 /* If .code addresses are different, the frames are different. */
316 else if (l.special_addr == 0 || r.special_addr == 0)
317 /* A zero special addr is a wild card (or unused), always succeed. */
319 else if (l.special_addr == r.special_addr)
320 /* Frames are equal. */
327 fprintf_unfiltered (gdb_stdlog, "{ frame_id_eq (l=");
328 fprint_frame_id (gdb_stdlog, l);
329 fprintf_unfiltered (gdb_stdlog, ",r=");
330 fprint_frame_id (gdb_stdlog, r);
331 fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", eq);
337 frame_id_inner (struct frame_id l, struct frame_id r)
340 if (l.stack_addr == 0 || r.stack_addr == 0)
341 /* Like NaN, any operation involving an invalid ID always fails. */
344 /* Only return non-zero when strictly inner than. Note that, per
345 comment in "frame.h", there is some fuzz here. Frameless
346 functions are not strictly inner than (same .stack but
347 different .code and/or .special address). */
348 inner = INNER_THAN (l.stack_addr, r.stack_addr);
351 fprintf_unfiltered (gdb_stdlog, "{ frame_id_inner (l=");
352 fprint_frame_id (gdb_stdlog, l);
353 fprintf_unfiltered (gdb_stdlog, ",r=");
354 fprint_frame_id (gdb_stdlog, r);
355 fprintf_unfiltered (gdb_stdlog, ") -> %d }\n", inner);
361 frame_find_by_id (struct frame_id id)
363 struct frame_info *frame;
365 /* ZERO denotes the null frame, let the caller decide what to do
366 about it. Should it instead return get_current_frame()? */
367 if (!frame_id_p (id))
370 for (frame = get_current_frame ();
372 frame = get_prev_frame (frame))
374 struct frame_id this = get_frame_id (frame);
375 if (frame_id_eq (id, this))
376 /* An exact match. */
378 if (frame_id_inner (id, this))
381 /* Either we're not yet gone far enough out along the frame
382 chain (inner(this,id)), or we're comparing frameless functions
383 (same .base, different .func, no test available). Struggle
384 on until we've definitly gone to far. */
390 frame_pc_unwind (struct frame_info *this_frame)
392 if (!this_frame->prev_pc.p)
395 if (gdbarch_unwind_pc_p (current_gdbarch))
397 /* The right way. The `pure' way. The one true way. This
398 method depends solely on the register-unwind code to
399 determine the value of registers in THIS frame, and hence
400 the value of this frame's PC (resume address). A typical
401 implementation is no more than:
403 frame_unwind_register (this_frame, ISA_PC_REGNUM, buf);
404 return extract_unsigned_integer (buf, size of ISA_PC_REGNUM);
406 Note: this method is very heavily dependent on a correct
407 register-unwind implementation, it pays to fix that
408 method first; this method is frame type agnostic, since
409 it only deals with register values, it works with any
410 frame. This is all in stark contrast to the old
411 FRAME_SAVED_PC which would try to directly handle all the
412 different ways that a PC could be unwound. */
413 pc = gdbarch_unwind_pc (current_gdbarch, this_frame);
415 else if (this_frame->level < 0)
417 /* FIXME: cagney/2003-03-06: Old code and a sentinel
418 frame. Do like was always done. Fetch the PC's value
419 directly from the global registers array (via read_pc).
420 This assumes that this frame belongs to the current
421 global register cache. The assumption is dangerous. */
424 else if (DEPRECATED_FRAME_SAVED_PC_P ())
426 /* FIXME: cagney/2003-03-06: Old code, but not a sentinel
427 frame. Do like was always done. Note that this method,
428 unlike unwind_pc(), tries to handle all the different
429 frame cases directly. It fails. */
430 pc = DEPRECATED_FRAME_SAVED_PC (this_frame);
433 internal_error (__FILE__, __LINE__, "No gdbarch_unwind_pc method");
434 this_frame->prev_pc.value = pc;
435 this_frame->prev_pc.p = 1;
437 fprintf_unfiltered (gdb_stdlog,
438 "{ frame_pc_unwind (this_frame=%d) -> 0x%s }\n",
440 paddr_nz (this_frame->prev_pc.value));
442 return this_frame->prev_pc.value;
446 frame_func_unwind (struct frame_info *fi)
448 if (!fi->prev_func.p)
450 /* Make certain that this, and not the adjacent, function is
452 CORE_ADDR addr_in_block = frame_unwind_address_in_block (fi);
454 fi->prev_func.addr = get_pc_function_start (addr_in_block);
456 fprintf_unfiltered (gdb_stdlog,
457 "{ frame_func_unwind (fi=%d) -> 0x%s }\n",
458 fi->level, paddr_nz (fi->prev_func.addr));
460 return fi->prev_func.addr;
464 get_frame_func (struct frame_info *fi)
466 return frame_func_unwind (fi->next);
470 do_frame_unwind_register (void *src, int regnum, void *buf)
472 frame_unwind_register (src, regnum, buf);
477 frame_pop (struct frame_info *this_frame)
479 struct regcache *scratch_regcache;
480 struct cleanup *cleanups;
482 if (DEPRECATED_POP_FRAME_P ())
484 /* A legacy architecture that has implemented a custom pop
485 function. All new architectures should instead be using the
486 generic code below. */
487 DEPRECATED_POP_FRAME;
491 /* Make a copy of all the register values unwound from this
492 frame. Save them in a scratch buffer so that there isn't a
493 race between trying to extract the old values from the
494 current_regcache while at the same time writing new values
495 into that same cache. */
496 struct regcache *scratch = regcache_xmalloc (current_gdbarch);
497 struct cleanup *cleanups = make_cleanup_regcache_xfree (scratch);
498 regcache_save (scratch, do_frame_unwind_register, this_frame);
499 /* FIXME: cagney/2003-03-16: It should be possible to tell the
500 target's register cache that it is about to be hit with a
501 burst register transfer and that the sequence of register
502 writes should be batched. The pair target_prepare_to_store()
503 and target_store_registers() kind of suggest this
504 functionality. Unfortunately, they don't implement it. Their
505 lack of a formal definition can lead to targets writing back
506 bogus values (arguably a bug in the target code mind). */
507 /* Now copy those saved registers into the current regcache.
508 Here, regcache_cpy() calls regcache_restore(). */
509 regcache_cpy (current_regcache, scratch);
510 do_cleanups (cleanups);
512 /* We've made right mess of GDB's local state, just discard
514 flush_cached_frames ();
518 frame_register_unwind (struct frame_info *frame, int regnum,
519 int *optimizedp, enum lval_type *lvalp,
520 CORE_ADDR *addrp, int *realnump, void *bufferp)
522 struct frame_unwind_cache *cache;
526 fprintf_unfiltered (gdb_stdlog, "\
527 { frame_register_unwind (frame=%d,regnum=%d(%s),...) ",
528 frame->level, regnum,
529 frame_map_regnum_to_name (frame, regnum));
532 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
533 that the value proper does not need to be fetched. */
534 gdb_assert (optimizedp != NULL);
535 gdb_assert (lvalp != NULL);
536 gdb_assert (addrp != NULL);
537 gdb_assert (realnump != NULL);
538 /* gdb_assert (bufferp != NULL); */
540 /* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame
541 is broken. There is always a frame. If there, for some reason,
542 isn't a frame, there is some pretty busted code as it should have
543 detected the problem before calling here. */
544 gdb_assert (frame != NULL);
546 /* Find the unwinder. */
547 if (frame->unwind == NULL)
549 frame->unwind = frame_unwind_find_by_frame (frame->next,
550 &frame->prologue_cache);
551 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
552 type in the frame, the unwinder's type should be returned
553 directly. Unfortunately, legacy code, called by
554 legacy_get_prev_frame(), explicitly set the frames type using
555 the method deprecated_set_frame_type(). */
556 frame->type = frame->unwind->type;
559 /* Ask this frame to unwind its register. See comment in
560 "frame-unwind.h" for why NEXT frame and this unwind cache are
562 frame->unwind->prev_register (frame->next, &frame->prologue_cache, regnum,
563 optimizedp, lvalp, addrp, realnump, bufferp);
567 fprintf_unfiltered (gdb_stdlog, "->");
568 fprintf_unfiltered (gdb_stdlog, " *optimizedp=%d", (*optimizedp));
569 fprintf_unfiltered (gdb_stdlog, " *lvalp=%d", (int) (*lvalp));
570 fprintf_unfiltered (gdb_stdlog, " *addrp=0x%s", paddr_nz ((*addrp)));
571 fprintf_unfiltered (gdb_stdlog, " *bufferp=");
573 fprintf_unfiltered (gdb_stdlog, "<NULL>");
577 const unsigned char *buf = bufferp;
578 fprintf_unfiltered (gdb_stdlog, "[");
579 for (i = 0; i < register_size (current_gdbarch, regnum); i++)
580 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
581 fprintf_unfiltered (gdb_stdlog, "]");
583 fprintf_unfiltered (gdb_stdlog, " }\n");
588 frame_register (struct frame_info *frame, int regnum,
589 int *optimizedp, enum lval_type *lvalp,
590 CORE_ADDR *addrp, int *realnump, void *bufferp)
592 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
593 that the value proper does not need to be fetched. */
594 gdb_assert (optimizedp != NULL);
595 gdb_assert (lvalp != NULL);
596 gdb_assert (addrp != NULL);
597 gdb_assert (realnump != NULL);
598 /* gdb_assert (bufferp != NULL); */
600 /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
601 of the register in the register cache. It should instead return
602 the REGNUM corresponding to that register. Translate the . */
603 if (DEPRECATED_GET_SAVED_REGISTER_P ())
605 DEPRECATED_GET_SAVED_REGISTER (bufferp, optimizedp, addrp, frame,
607 /* Compute the REALNUM if the caller wants it. */
608 if (*lvalp == lval_register)
611 for (regnum = 0; regnum < NUM_REGS + NUM_PSEUDO_REGS; regnum++)
613 if (*addrp == register_offset_hack (current_gdbarch, regnum))
619 internal_error (__FILE__, __LINE__,
620 "Failed to compute the register number corresponding"
621 " to 0x%s", paddr_d (*addrp));
627 /* Obtain the register value by unwinding the register from the next
628 (more inner frame). */
629 gdb_assert (frame != NULL && frame->next != NULL);
630 frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
635 frame_unwind_register (struct frame_info *frame, int regnum, void *buf)
641 frame_register_unwind (frame, regnum, &optimized, &lval, &addr,
646 get_frame_register (struct frame_info *frame,
647 int regnum, void *buf)
649 frame_unwind_register (frame->next, regnum, buf);
653 frame_unwind_register_signed (struct frame_info *frame, int regnum)
655 char buf[MAX_REGISTER_SIZE];
656 frame_unwind_register (frame, regnum, buf);
657 return extract_signed_integer (buf, DEPRECATED_REGISTER_VIRTUAL_SIZE (regnum));
661 get_frame_register_signed (struct frame_info *frame, int regnum)
663 return frame_unwind_register_signed (frame->next, regnum);
667 frame_unwind_register_unsigned (struct frame_info *frame, int regnum)
669 char buf[MAX_REGISTER_SIZE];
670 frame_unwind_register (frame, regnum, buf);
671 return extract_unsigned_integer (buf, DEPRECATED_REGISTER_VIRTUAL_SIZE (regnum));
675 get_frame_register_unsigned (struct frame_info *frame, int regnum)
677 return frame_unwind_register_unsigned (frame->next, regnum);
681 frame_unwind_unsigned_register (struct frame_info *frame, int regnum,
684 char buf[MAX_REGISTER_SIZE];
685 frame_unwind_register (frame, regnum, buf);
686 (*val) = extract_unsigned_integer (buf, DEPRECATED_REGISTER_VIRTUAL_SIZE (regnum));
690 put_frame_register (struct frame_info *frame, int regnum, const void *buf)
692 struct gdbarch *gdbarch = get_frame_arch (frame);
697 frame_register (frame, regnum, &optim, &lval, &addr, &realnum, NULL);
699 error ("Attempt to assign to a value that was optimized out.");
704 /* FIXME: write_memory doesn't yet take constant buffers.
706 char tmp[MAX_REGISTER_SIZE];
707 memcpy (tmp, buf, register_size (gdbarch, regnum));
708 write_memory (addr, tmp, register_size (gdbarch, regnum));
712 regcache_cooked_write (current_regcache, realnum, buf);
715 error ("Attempt to assign to an unmodifiable value.");
719 /* frame_register_read ()
721 Find and return the value of REGNUM for the specified stack frame.
722 The number of bytes copied is DEPRECATED_REGISTER_RAW_SIZE
725 Returns 0 if the register value could not be found. */
728 frame_register_read (struct frame_info *frame, int regnum, void *myaddr)
734 frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
736 /* FIXME: cagney/2002-05-15: This test is just bogus.
738 It indicates that the target failed to supply a value for a
739 register because it was "not available" at this time. Problem
740 is, the target still has the register and so get saved_register()
741 may be returning a value saved on the stack. */
743 if (register_cached (regnum) < 0)
744 return 0; /* register value not available */
750 /* Map between a frame register number and its name. A frame register
751 space is a superset of the cooked register space --- it also
752 includes builtin registers. */
755 frame_map_name_to_regnum (struct frame_info *frame, const char *name, int len)
757 return user_reg_map_name_to_regnum (get_frame_arch (frame), name, len);
761 frame_map_regnum_to_name (struct frame_info *frame, int regnum)
763 return user_reg_map_regnum_to_name (get_frame_arch (frame), regnum);
766 /* Create a sentinel frame. */
768 static struct frame_info *
769 create_sentinel_frame (struct regcache *regcache)
771 struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
772 frame->type = NORMAL_FRAME;
774 /* Explicitly initialize the sentinel frame's cache. Provide it
775 with the underlying regcache. In the future additional
776 information, such as the frame's thread will be added. */
777 frame->prologue_cache = sentinel_frame_cache (regcache);
778 /* For the moment there is only one sentinel frame implementation. */
779 frame->unwind = sentinel_frame_unwind;
780 /* Link this frame back to itself. The frame is self referential
781 (the unwound PC is the same as the pc), so make it so. */
783 /* Make the sentinel frame's ID valid, but invalid. That way all
784 comparisons with it should fail. */
785 frame->this_id.p = 1;
786 frame->this_id.value = null_frame_id;
789 fprintf_unfiltered (gdb_stdlog, "{ create_sentinel_frame (...) -> ");
790 fprint_frame (gdb_stdlog, frame);
791 fprintf_unfiltered (gdb_stdlog, " }\n");
796 /* Info about the innermost stack frame (contents of FP register) */
798 static struct frame_info *current_frame;
800 /* Cache for frame addresses already read by gdb. Valid only while
801 inferior is stopped. Control variables for the frame cache should
802 be local to this module. */
804 static struct obstack frame_cache_obstack;
807 frame_obstack_zalloc (unsigned long size)
809 void *data = obstack_alloc (&frame_cache_obstack, size);
810 memset (data, 0, size);
815 frame_saved_regs_zalloc (struct frame_info *fi)
817 fi->saved_regs = (CORE_ADDR *)
818 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS);
819 return fi->saved_regs;
823 deprecated_get_frame_saved_regs (struct frame_info *fi)
825 return fi->saved_regs;
828 /* Return the innermost (currently executing) stack frame. This is
829 split into two functions. The function unwind_to_current_frame()
830 is wrapped in catch exceptions so that, even when the unwind of the
831 sentinel frame fails, the function still returns a stack frame. */
834 unwind_to_current_frame (struct ui_out *ui_out, void *args)
836 struct frame_info *frame = get_prev_frame (args);
837 /* A sentinel frame can fail to unwind, e.g., because its PC value
838 lands in somewhere like start. */
841 current_frame = frame;
846 get_current_frame (void)
848 /* First check, and report, the lack of registers. Having GDB
849 report "No stack!" or "No memory" when the target doesn't even
850 have registers is very confusing. Besides, "printcmd.exp"
851 explicitly checks that ``print $pc'' with no registers prints "No
853 if (!target_has_registers)
854 error ("No registers.");
855 if (!target_has_stack)
857 if (!target_has_memory)
858 error ("No memory.");
859 if (current_frame == NULL)
861 struct frame_info *sentinel_frame =
862 create_sentinel_frame (current_regcache);
863 if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
864 NULL, RETURN_MASK_ERROR) != 0)
866 /* Oops! Fake a current frame? Is this useful? It has a PC
867 of zero, for instance. */
868 current_frame = sentinel_frame;
871 return current_frame;
874 /* The "selected" stack frame is used by default for local and arg
875 access. May be zero, for no selected frame. */
877 struct frame_info *deprecated_selected_frame;
879 /* Return the selected frame. Always non-NULL (unless there isn't an
880 inferior sufficient for creating a frame) in which case an error is
884 get_selected_frame (void)
886 if (deprecated_selected_frame == NULL)
887 /* Hey! Don't trust this. It should really be re-finding the
888 last selected frame of the currently selected thread. This,
889 though, is better than nothing. */
890 select_frame (get_current_frame ());
891 /* There is always a frame. */
892 gdb_assert (deprecated_selected_frame != NULL);
893 return deprecated_selected_frame;
896 /* This is a variant of get_selected_frame() which can be called when
897 the inferior does not have a frame; in that case it will return
898 NULL instead of calling error(). */
901 deprecated_safe_get_selected_frame (void)
903 if (!target_has_registers || !target_has_stack || !target_has_memory)
905 return get_selected_frame ();
908 /* Select frame FI (or NULL - to invalidate the current frame). */
911 select_frame (struct frame_info *fi)
915 deprecated_selected_frame = fi;
916 /* NOTE: cagney/2002-05-04: FI can be NULL. This occurs when the
917 frame is being invalidated. */
918 if (deprecated_selected_frame_level_changed_hook)
919 deprecated_selected_frame_level_changed_hook (frame_relative_level (fi));
921 /* FIXME: kseitz/2002-08-28: It would be nice to call
922 selected_frame_level_changed_event() right here, but due to limitations
923 in the current interfaces, we would end up flooding UIs with events
924 because select_frame() is used extensively internally.
926 Once we have frame-parameterized frame (and frame-related) commands,
927 the event notification can be moved here, since this function will only
928 be called when the user's selected frame is being changed. */
930 /* Ensure that symbols for this frame are read in. Also, determine the
931 source language of this frame, and switch to it if desired. */
934 /* We retrieve the frame's symtab by using the frame PC. However
935 we cannot use the frame PC as-is, because it usually points to
936 the instruction following the "call", which is sometimes the
937 first instruction of another function. So we rely on
938 get_frame_address_in_block() which provides us with a PC which
939 is guaranteed to be inside the frame's code block. */
940 s = find_pc_symtab (get_frame_address_in_block (fi));
942 && s->language != current_language->la_language
943 && s->language != language_unknown
944 && language_mode == language_mode_auto)
946 set_language (s->language);
951 /* Return the register saved in the simplistic ``saved_regs'' cache.
952 If the value isn't here AND a value is needed, try the next inner
956 legacy_saved_regs_prev_register (struct frame_info *next_frame,
957 void **this_prologue_cache,
958 int regnum, int *optimizedp,
959 enum lval_type *lvalp, CORE_ADDR *addrp,
960 int *realnump, void *bufferp)
962 /* HACK: New code is passed the next frame and this cache.
963 Unfortunately, old code expects this frame. Since this is a
964 backward compatibility hack, cheat by walking one level along the
965 prologue chain to the frame the old code expects.
967 Do not try this at home. Professional driver, closed course. */
968 struct frame_info *frame = next_frame->prev;
969 gdb_assert (frame != NULL);
971 if (deprecated_get_frame_saved_regs (frame) == NULL)
973 /* If nothing has initialized the saved regs, do it now. */
974 gdb_assert (DEPRECATED_FRAME_INIT_SAVED_REGS_P ());
975 DEPRECATED_FRAME_INIT_SAVED_REGS (frame);
976 gdb_assert (deprecated_get_frame_saved_regs (frame) != NULL);
979 if (deprecated_get_frame_saved_regs (frame) != NULL
980 && deprecated_get_frame_saved_regs (frame)[regnum] != 0)
982 if (regnum == SP_REGNUM)
984 /* SP register treated specially. */
990 /* NOTE: cagney/2003-05-09: In-lined store_address() with
991 it's body - store_unsigned_integer(). */
992 store_unsigned_integer (bufferp, DEPRECATED_REGISTER_RAW_SIZE (regnum),
993 deprecated_get_frame_saved_regs (frame)[regnum]);
997 /* Any other register is saved in memory, fetch it but cache
998 a local copy of its value. */
1000 *lvalp = lval_memory;
1001 *addrp = deprecated_get_frame_saved_regs (frame)[regnum];
1003 if (bufferp != NULL)
1006 /* Save each register value, as it is read in, in a
1007 frame based cache. */
1008 void **regs = (*this_prologue_cache);
1011 int sizeof_cache = ((NUM_REGS + NUM_PSEUDO_REGS)
1013 regs = frame_obstack_zalloc (sizeof_cache);
1014 (*this_prologue_cache) = regs;
1016 if (regs[regnum] == NULL)
1019 = frame_obstack_zalloc (DEPRECATED_REGISTER_RAW_SIZE (regnum));
1020 read_memory (deprecated_get_frame_saved_regs (frame)[regnum], regs[regnum],
1021 DEPRECATED_REGISTER_RAW_SIZE (regnum));
1023 memcpy (bufferp, regs[regnum], DEPRECATED_REGISTER_RAW_SIZE (regnum));
1025 /* Read the value in from memory. */
1026 read_memory (deprecated_get_frame_saved_regs (frame)[regnum], bufferp,
1027 DEPRECATED_REGISTER_RAW_SIZE (regnum));
1034 /* No luck. Assume this and the next frame have the same register
1035 value. Pass the unwind request down the frame chain to the next
1036 frame. Hopefully that frame will find the register's location. */
1037 frame_register_unwind (next_frame, regnum, optimizedp, lvalp, addrp,
1042 legacy_saved_regs_this_id (struct frame_info *next_frame,
1043 void **this_prologue_cache,
1044 struct frame_id *id)
1046 /* A developer is trying to bring up a new architecture, help them
1047 by providing a default unwinder that refuses to unwind anything
1048 (the ID is always NULL). In the case of legacy code,
1049 legacy_get_prev_frame() will have previously set ->this_id.p, so
1050 this code won't be called. */
1051 (*id) = null_frame_id;
1054 const struct frame_unwind legacy_saved_regs_unwinder = {
1055 /* Not really. It gets overridden by legacy_get_prev_frame(). */
1057 legacy_saved_regs_this_id,
1058 legacy_saved_regs_prev_register
1060 const struct frame_unwind *legacy_saved_regs_unwind = &legacy_saved_regs_unwinder;
1063 /* Function: deprecated_generic_get_saved_register
1064 Find register number REGNUM relative to FRAME and put its (raw,
1065 target format) contents in *RAW_BUFFER.
1067 Set *OPTIMIZED if the variable was optimized out (and thus can't be
1068 fetched). Note that this is never set to anything other than zero
1069 in this implementation.
1071 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
1072 whether the value was fetched from memory, from a register, or in a
1073 strange and non-modifiable way (e.g. a frame pointer which was
1074 calculated rather than fetched). We will use not_lval for values
1075 fetched from generic dummy frames.
1077 Set *ADDRP to the address, either in memory or as a
1078 DEPRECATED_REGISTER_BYTE offset into the registers array. If the
1079 value is stored in a dummy frame, set *ADDRP to zero.
1081 The argument RAW_BUFFER must point to aligned memory. */
1084 deprecated_generic_get_saved_register (char *raw_buffer, int *optimized,
1086 struct frame_info *frame, int regnum,
1087 enum lval_type *lval)
1089 if (!target_has_registers)
1090 error ("No registers.");
1092 /* Normal systems don't optimize out things with register numbers. */
1093 if (optimized != NULL)
1096 if (addrp) /* default assumption: not found in memory */
1099 /* Note: since the current frame's registers could only have been
1100 saved by frames INTERIOR TO the current frame, we skip examining
1101 the current frame itself: otherwise, we would be getting the
1102 previous frame's registers which were saved by the current frame. */
1106 for (frame = get_next_frame (frame);
1107 frame_relative_level (frame) >= 0;
1108 frame = get_next_frame (frame))
1110 if (get_frame_type (frame) == DUMMY_FRAME)
1112 if (lval) /* found it in a CALL_DUMMY frame */
1115 /* FIXME: cagney/2002-06-26: This should be via the
1116 gdbarch_register_read() method so that it, on the
1117 fly, constructs either a raw or pseudo register
1118 from the raw register cache. */
1120 (deprecated_find_dummy_frame_regcache (get_frame_pc (frame),
1121 get_frame_base (frame)),
1122 regnum, raw_buffer);
1126 DEPRECATED_FRAME_INIT_SAVED_REGS (frame);
1127 if (deprecated_get_frame_saved_regs (frame) != NULL
1128 && deprecated_get_frame_saved_regs (frame)[regnum] != 0)
1130 if (lval) /* found it saved on the stack */
1131 *lval = lval_memory;
1132 if (regnum == SP_REGNUM)
1134 if (raw_buffer) /* SP register treated specially */
1135 /* NOTE: cagney/2003-05-09: In-line store_address()
1136 with it's body - store_unsigned_integer(). */
1137 store_unsigned_integer (raw_buffer,
1138 DEPRECATED_REGISTER_RAW_SIZE (regnum),
1139 deprecated_get_frame_saved_regs (frame)[regnum]);
1143 if (addrp) /* any other register */
1144 *addrp = deprecated_get_frame_saved_regs (frame)[regnum];
1146 read_memory (deprecated_get_frame_saved_regs (frame)[regnum], raw_buffer,
1147 DEPRECATED_REGISTER_RAW_SIZE (regnum));
1154 /* If we get thru the loop to this point, it means the register was
1155 not saved in any frame. Return the actual live-register value. */
1157 if (lval) /* found it in a live register */
1158 *lval = lval_register;
1160 *addrp = DEPRECATED_REGISTER_BYTE (regnum);
1162 deprecated_read_register_gen (regnum, raw_buffer);
1165 /* Determine the frame's type based on its PC. */
1167 static enum frame_type
1168 frame_type_from_pc (CORE_ADDR pc)
1170 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1171 && deprecated_pc_in_call_dummy (pc, 0, 0))
1176 find_pc_partial_function (pc, &name, NULL, NULL);
1177 if (DEPRECATED_PC_IN_SIGTRAMP (pc, name))
1178 return SIGTRAMP_FRAME;
1180 return NORMAL_FRAME;
1184 /* Create an arbitrary (i.e. address specified by user) or innermost frame.
1185 Always returns a non-NULL value. */
1188 create_new_frame (CORE_ADDR addr, CORE_ADDR pc)
1190 struct frame_info *fi;
1194 fprintf_unfiltered (gdb_stdlog,
1195 "{ create_new_frame (addr=0x%s, pc=0x%s) ",
1196 paddr_nz (addr), paddr_nz (pc));
1199 fi = frame_obstack_zalloc (sizeof (struct frame_info));
1201 fi->next = create_sentinel_frame (current_regcache);
1203 /* Select/initialize both the unwind function and the frame's type
1205 fi->unwind = frame_unwind_find_by_frame (fi->next, &fi->prologue_cache);
1206 if (fi->unwind->type != UNKNOWN_FRAME)
1207 fi->type = fi->unwind->type;
1209 fi->type = frame_type_from_pc (pc);
1212 deprecated_update_frame_base_hack (fi, addr);
1213 deprecated_update_frame_pc_hack (fi, pc);
1215 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1216 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, fi);
1220 fprintf_unfiltered (gdb_stdlog, "-> ");
1221 fprint_frame (gdb_stdlog, fi);
1222 fprintf_unfiltered (gdb_stdlog, " }\n");
1228 /* Return the frame that THIS_FRAME calls (NULL if THIS_FRAME is the
1229 innermost frame). Be careful to not fall off the bottom of the
1230 frame chain and onto the sentinel frame. */
1233 get_next_frame (struct frame_info *this_frame)
1235 if (this_frame->level > 0)
1236 return this_frame->next;
1241 /* Observer for the target_changed event. */
1244 frame_observer_target_changed (struct target_ops *target)
1246 flush_cached_frames ();
1249 /* Flush the entire frame cache. */
1252 flush_cached_frames (void)
1254 /* Since we can't really be sure what the first object allocated was */
1255 obstack_free (&frame_cache_obstack, 0);
1256 obstack_init (&frame_cache_obstack);
1258 current_frame = NULL; /* Invalidate cache */
1259 select_frame (NULL);
1260 annotate_frames_invalid ();
1262 fprintf_unfiltered (gdb_stdlog, "{ flush_cached_frames () }\n");
1265 /* Flush the frame cache, and start a new one if necessary. */
1268 reinit_frame_cache (void)
1270 flush_cached_frames ();
1272 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
1273 if (PIDGET (inferior_ptid) != 0)
1275 select_frame (get_current_frame ());
1279 /* Create the previous frame using the deprecated methods
1280 INIT_EXTRA_INFO, and INIT_FRAME_PC. */
1282 static struct frame_info *
1283 legacy_get_prev_frame (struct frame_info *this_frame)
1285 CORE_ADDR address = 0;
1286 struct frame_info *prev;
1289 /* Don't frame_debug print legacy_get_prev_frame() here, just
1290 confuses the output. */
1292 /* Allocate the new frame.
1294 There is no reason to worry about memory leaks, should the
1295 remainder of the function fail. The allocated memory will be
1296 quickly reclaimed when the frame cache is flushed, and the `we've
1297 been here before' check, in get_prev_frame() will stop repeated
1298 memory allocation calls. */
1299 prev = FRAME_OBSTACK_ZALLOC (struct frame_info);
1300 prev->level = this_frame->level + 1;
1302 /* Do not completely wire it in to the frame chain. Some (bad) code
1303 in INIT_FRAME_EXTRA_INFO tries to look along frame->prev to pull
1304 some fancy tricks (of course such code is, by definition,
1307 On the other hand, methods, such as get_frame_pc() and
1308 get_frame_base() rely on being able to walk along the frame
1309 chain. Make certain that at least they work by providing that
1310 link. Of course things manipulating prev can't go back. */
1311 prev->next = this_frame;
1313 /* NOTE: cagney/2002-11-18: Should have been correctly setting the
1314 frame's type here, before anything else, and not last, at the
1315 bottom of this function. The various
1316 DEPRECATED_INIT_EXTRA_FRAME_INFO, DEPRECATED_INIT_FRAME_PC, and
1317 DEPRECATED_FRAME_INIT_SAVED_REGS methods are full of work-arounds
1318 that handle the frame not being correctly set from the start.
1319 Unfortunately those same work-arounds rely on the type defaulting
1320 to NORMAL_FRAME. Ulgh! The new frame code does not have this
1322 prev->type = UNKNOWN_FRAME;
1324 /* A legacy frame's ID is always computed here. Mark it as valid. */
1325 prev->this_id.p = 1;
1327 /* Handle sentinel frame unwind as a special case. */
1328 if (this_frame->level < 0)
1330 /* Try to unwind the PC. If that doesn't work, assume we've reached
1331 the oldest frame and simply return. Is there a better sentinal
1332 value? The unwound PC value is then used to initialize the new
1333 previous frame's type.
1335 Note that the pc-unwind is intentionally performed before the
1336 frame chain. This is ok since, for old targets, both
1337 frame_pc_unwind() (nee, DEPRECATED_FRAME_SAVED_PC) and
1338 DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
1339 have already been initialized (using
1340 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1343 By unwinding the PC first, it becomes possible to, in the case of
1344 a dummy frame, avoid also unwinding the frame ID. This is
1345 because (well ignoring the PPC) a dummy frame can be located
1346 using THIS_FRAME's frame ID. */
1348 deprecated_update_frame_pc_hack (prev, frame_pc_unwind (this_frame));
1349 if (get_frame_pc (prev) == 0)
1351 /* The allocated PREV_FRAME will be reclaimed when the frame
1352 obstack is next purged. */
1355 fprintf_unfiltered (gdb_stdlog, "-> ");
1356 fprint_frame (gdb_stdlog, NULL);
1357 fprintf_unfiltered (gdb_stdlog,
1358 " // unwound legacy PC zero }\n");
1363 /* Set the unwind functions based on that identified PC. Ditto
1364 for the "type" but strongly prefer the unwinder's frame type. */
1365 prev->unwind = frame_unwind_find_by_frame (prev->next,
1366 &prev->prologue_cache);
1367 if (prev->unwind->type == UNKNOWN_FRAME)
1368 prev->type = frame_type_from_pc (get_frame_pc (prev));
1370 prev->type = prev->unwind->type;
1372 /* Find the prev's frame's ID. */
1373 if (prev->type == DUMMY_FRAME
1374 && gdbarch_unwind_dummy_id_p (current_gdbarch))
1376 /* When unwinding a normal frame, the stack structure is
1377 determined by analyzing the frame's function's code (be
1378 it using brute force prologue analysis, or the dwarf2
1379 CFI). In the case of a dummy frame, that simply isn't
1380 possible. The The PC is either the program entry point,
1381 or some random address on the stack. Trying to use that
1382 PC to apply standard frame ID unwind techniques is just
1383 asking for trouble. */
1384 /* Use an architecture specific method to extract the prev's
1385 dummy ID from the next frame. Note that this method uses
1386 frame_register_unwind to obtain the register values
1387 needed to determine the dummy frame's ID. */
1388 prev->this_id.value = gdbarch_unwind_dummy_id (current_gdbarch,
1393 /* We're unwinding a sentinel frame, the PC of which is
1394 pointing at a stack dummy. Fake up the dummy frame's ID
1395 using the same sequence as is found a traditional
1396 unwinder. Once all architectures supply the
1397 unwind_dummy_id method, this code can go away. */
1398 prev->this_id.value = frame_id_build (deprecated_read_fp (),
1402 /* Check that the unwound ID is valid. */
1403 if (!frame_id_p (prev->this_id.value))
1407 fprintf_unfiltered (gdb_stdlog, "-> ");
1408 fprint_frame (gdb_stdlog, NULL);
1409 fprintf_unfiltered (gdb_stdlog,
1410 " // unwound legacy ID invalid }\n");
1415 /* Check that the new frame isn't inner to (younger, below,
1416 next) the old frame. If that happens the frame unwind is
1418 /* FIXME: cagney/2003-02-25: Ignore the sentinel frame since
1419 that doesn't have a valid frame ID. Should instead set the
1420 sentinel frame's frame ID to a `sentinel'. Leave it until
1421 after the switch to storing the frame ID, instead of the
1422 frame base, in the frame object. */
1425 this_frame->prev = prev;
1427 /* FIXME: cagney/2002-01-19: This call will go away. Instead of
1428 initializing extra info, all frames will use the frame_cache
1429 (passed to the unwind functions) to store additional frame
1430 info. Unfortunately legacy targets can't use
1431 legacy_get_prev_frame() to unwind the sentinel frame and,
1432 consequently, are forced to take this code path and rely on
1433 the below call to DEPRECATED_INIT_EXTRA_FRAME_INFO to
1434 initialize the inner-most frame. */
1435 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1437 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, prev);
1440 if (prev->type == NORMAL_FRAME)
1441 prev->this_id.value.code_addr
1442 = get_pc_function_start (prev->this_id.value.code_addr);
1446 fprintf_unfiltered (gdb_stdlog, "-> ");
1447 fprint_frame (gdb_stdlog, prev);
1448 fprintf_unfiltered (gdb_stdlog, " } // legacy innermost frame\n");
1453 /* This code only works on normal frames. A sentinel frame, where
1454 the level is -1, should never reach this code. */
1455 gdb_assert (this_frame->level >= 0);
1457 /* On some machines it is possible to call a function without
1458 setting up a stack frame for it. On these machines, we
1459 define this macro to take two args; a frameinfo pointer
1460 identifying a frame and a variable to set or clear if it is
1461 or isn't leafless. */
1463 /* Still don't want to worry about this except on the innermost
1464 frame. This macro will set FROMLEAF if THIS_FRAME is a frameless
1465 function invocation. */
1466 if (this_frame->level == 0)
1467 /* FIXME: 2002-11-09: Frameless functions can occur anywhere in
1468 the frame chain, not just the inner most frame! The generic,
1469 per-architecture, frame code should handle this and the below
1470 should simply be removed. */
1471 fromleaf = (DEPRECATED_FRAMELESS_FUNCTION_INVOCATION_P ()
1472 && DEPRECATED_FRAMELESS_FUNCTION_INVOCATION (this_frame));
1477 /* A frameless inner-most frame. The `FP' (which isn't an
1478 architecture frame-pointer register!) of the caller is the same
1480 /* FIXME: 2002-11-09: There isn't any reason to special case this
1481 edge condition. Instead the per-architecture code should handle
1483 /* FIXME: cagney/2003-06-16: This returns the inner most stack
1484 address for the previous frame, that, however, is wrong. It
1485 should be the inner most stack address for the previous to
1486 previous frame. This is because it is the previous to previous
1487 frame's innermost stack address that is constant through out
1488 the lifetime of the previous frame (trust me :-). */
1489 address = get_frame_base (this_frame);
1492 /* Two macros defined in tm.h specify the machine-dependent
1493 actions to be performed here.
1495 First, get the frame's chain-pointer.
1497 If that is zero, the frame is the outermost frame or a leaf
1498 called by the outermost frame. This means that if start
1499 calls main without a frame, we'll return 0 (which is fine
1502 Nope; there's a problem. This also returns when the current
1503 routine is a leaf of main. This is unacceptable. We move
1504 this to after the ffi test; I'd rather have backtraces from
1505 start go curfluy than have an abort called from main not show
1507 if (DEPRECATED_FRAME_CHAIN_P ())
1508 address = DEPRECATED_FRAME_CHAIN (this_frame);
1511 /* Someone is part way through coverting an old architecture
1512 to the new frame code. Implement FRAME_CHAIN the way the
1514 /* Find PREV frame's unwinder. */
1515 prev->unwind = frame_unwind_find_by_frame (this_frame,
1516 &prev->prologue_cache);
1517 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
1518 type in the frame, the unwinder's type should be returned
1519 directly. Unfortunately, legacy code, called by
1520 legacy_get_prev_frame(), explicitly set the frames type
1521 using the method deprecated_set_frame_type(). */
1522 prev->type = prev->unwind->type;
1523 /* Find PREV frame's ID. */
1524 prev->unwind->this_id (this_frame,
1525 &prev->prologue_cache,
1526 &prev->this_id.value);
1527 prev->this_id.p = 1;
1528 address = prev->this_id.value.stack_addr;
1531 if (!legacy_frame_chain_valid (address, this_frame))
1535 fprintf_unfiltered (gdb_stdlog, "-> ");
1536 fprint_frame (gdb_stdlog, NULL);
1537 fprintf_unfiltered (gdb_stdlog,
1538 " // legacy frame chain invalid }\n");
1547 fprintf_unfiltered (gdb_stdlog, "-> ");
1548 fprint_frame (gdb_stdlog, NULL);
1549 fprintf_unfiltered (gdb_stdlog,
1550 " // legacy frame chain NULL }\n");
1555 /* Link in the already allocated prev frame. */
1556 this_frame->prev = prev;
1557 deprecated_update_frame_base_hack (prev, address);
1559 /* This change should not be needed, FIXME! We should determine
1560 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1561 after DEPRECATED_INIT_EXTRA_FRAME_INFO and come up with a simple
1562 way to express what goes on here.
1564 DEPRECATED_INIT_EXTRA_FRAME_INFO is called from two places:
1565 create_new_frame (where the PC is already set up) and here (where
1566 it isn't). DEPRECATED_INIT_FRAME_PC is only called from here,
1567 always after DEPRECATED_INIT_EXTRA_FRAME_INFO.
1569 The catch is the MIPS, where DEPRECATED_INIT_EXTRA_FRAME_INFO
1570 requires the PC value (which hasn't been set yet). Some other
1571 machines appear to require DEPRECATED_INIT_EXTRA_FRAME_INFO
1572 before they can do DEPRECATED_INIT_FRAME_PC. Phoo.
1574 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
1575 DEPRECATED_INIT_EXTRA_FRAME_INFO, one possible scheme:
1577 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1578 (deprecated_read_fp ()), read_pc ()). Machines with extra frame
1579 info would do that (or the local equivalent) and then set the
1582 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1583 create_new_frame would no longer init extra frame info;
1584 SETUP_ARBITRARY_FRAME would have to do that.
1586 INIT_PREV_FRAME(fromleaf, prev) Replace
1587 DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC.
1588 This should also return a flag saying whether to keep the new
1589 frame, or whether to discard it, because on some machines (e.g.
1590 mips) it is really awkward to have DEPRECATED_FRAME_CHAIN_VALID
1591 called BEFORE DEPRECATED_INIT_EXTRA_FRAME_INFO (there is no good
1592 way to get information deduced in DEPRECATED_FRAME_CHAIN_VALID
1593 into the extra fields of the new frame). std_frame_pc(fromleaf,
1596 This is the default setting for INIT_PREV_FRAME. It just does
1597 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1598 will call it from INIT_PREV_FRAME (either at the beginning, the
1599 end, or in the middle). Some machines won't use it.
1601 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1603 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1604 reason for things to be this complicated.
1606 The trick is to assume that there is always a frame. Instead of
1607 special casing the inner-most frame, create a fake frame
1608 (containing the hardware registers) that is inner to the
1609 user-visible inner-most frame (...) and then unwind from that.
1610 That way architecture code can use the standard
1611 frame_XX_unwind() functions and not differentiate between the
1612 inner most and any other case.
1614 Since there is always a frame to unwind from, there is always
1615 somewhere (THIS_FRAME) to store all the info needed to construct
1616 a new (previous) frame without having to first create it. This
1617 means that the convolution below - needing to carefully order a
1618 frame's initialization - isn't needed.
1620 The irony here though, is that DEPRECATED_FRAME_CHAIN(), at least
1621 for a more up-to-date architecture, always calls
1622 FRAME_SAVED_PC(), and FRAME_SAVED_PC() computes the PC but
1623 without first needing the frame! Instead of the convolution
1624 below, we could have simply called FRAME_SAVED_PC() and been done
1625 with it! Note that FRAME_SAVED_PC() is being superseded by
1626 frame_pc_unwind() and that function does have somewhere to cache
1629 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1630 DEPRECATED_INIT_EXTRA_FRAME_INFO (fromleaf, prev);
1632 /* This entry is in the frame queue now, which is good since
1633 FRAME_SAVED_PC may use that queue to figure out its value (see
1634 tm-sparc.h). We want the PC saved in the inferior frame. */
1635 if (DEPRECATED_INIT_FRAME_PC_P ())
1636 deprecated_update_frame_pc_hack (prev,
1637 DEPRECATED_INIT_FRAME_PC (fromleaf,
1640 /* If ->frame and ->pc are unchanged, we are in the process of
1641 getting ourselves into an infinite backtrace. Some architectures
1642 check this in DEPRECATED_FRAME_CHAIN or thereabouts, but it seems
1643 like there is no reason this can't be an architecture-independent
1645 if (get_frame_base (prev) == get_frame_base (this_frame)
1646 && get_frame_pc (prev) == get_frame_pc (this_frame))
1648 this_frame->prev = NULL;
1649 obstack_free (&frame_cache_obstack, prev);
1652 fprintf_unfiltered (gdb_stdlog, "-> ");
1653 fprint_frame (gdb_stdlog, NULL);
1654 fprintf_unfiltered (gdb_stdlog,
1655 " // legacy this.id == prev.id }\n");
1660 /* Initialize the code used to unwind the frame PREV based on the PC
1661 (and probably other architectural information). The PC lets you
1662 check things like the debug info at that point (dwarf2cfi?) and
1663 use that to decide how the frame should be unwound.
1665 If there isn't a FRAME_CHAIN, the code above will have already
1667 if (prev->unwind == NULL)
1668 prev->unwind = frame_unwind_find_by_frame (prev->next,
1669 &prev->prologue_cache);
1671 /* If the unwinder provides a frame type, use it. Otherwise
1672 continue on to that heuristic mess. */
1673 if (prev->unwind->type != UNKNOWN_FRAME)
1675 prev->type = prev->unwind->type;
1676 if (prev->type == NORMAL_FRAME)
1677 /* FIXME: cagney/2003-06-16: would get_frame_pc() be better? */
1678 prev->this_id.value.code_addr
1679 = get_pc_function_start (prev->this_id.value.code_addr);
1682 fprintf_unfiltered (gdb_stdlog, "-> ");
1683 fprint_frame (gdb_stdlog, prev);
1684 fprintf_unfiltered (gdb_stdlog, " } // legacy with unwound type\n");
1689 /* NOTE: cagney/2002-11-18: The code segments, found in
1690 create_new_frame() and get_prev_frame(), that initialize the
1691 frame's type is subtly different. The latter only updates ->type
1692 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1693 get_prev_frame() overriding the frame's type when the INIT code
1694 has previously set it. This is really somewhat bogus. The
1695 initialization, as seen in create_new_frame(), should occur
1696 before the INIT function has been called. */
1697 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1698 && deprecated_pc_in_call_dummy (get_frame_pc (prev), 0, 0))
1699 prev->type = DUMMY_FRAME;
1702 /* FIXME: cagney/2002-11-10: This should be moved to before the
1703 INIT code above so that the INIT code knows what the frame's
1704 type is (in fact, for a [generic] dummy-frame, the type can
1705 be set and then the entire initialization can be skipped).
1706 Unfortunately, it's the INIT code that sets the PC (Hmm, catch
1709 find_pc_partial_function (get_frame_pc (prev), &name, NULL, NULL);
1710 if (DEPRECATED_PC_IN_SIGTRAMP (get_frame_pc (prev), name))
1711 prev->type = SIGTRAMP_FRAME;
1712 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1713 architectures are forcing the frame's type in INIT so we
1714 don't want to override it here. Remember, NORMAL_FRAME == 0,
1715 so it all works (just :-/). Once this initialization is
1716 moved to the start of this function, all this nastness will
1720 if (prev->type == NORMAL_FRAME)
1721 prev->this_id.value.code_addr
1722 = get_pc_function_start (prev->this_id.value.code_addr);
1726 fprintf_unfiltered (gdb_stdlog, "-> ");
1727 fprint_frame (gdb_stdlog, prev);
1728 fprintf_unfiltered (gdb_stdlog, " } // legacy with confused type\n");
1734 /* Return a "struct frame_info" corresponding to the frame that called
1735 THIS_FRAME. Returns NULL if there is no such frame.
1737 Unlike get_prev_frame, this function always tries to unwind the
1740 static struct frame_info *
1741 get_prev_frame_1 (struct frame_info *this_frame)
1743 struct frame_info *prev_frame;
1745 gdb_assert (this_frame != NULL);
1749 fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame_1 (this_frame=");
1750 if (this_frame != NULL)
1751 fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level);
1753 fprintf_unfiltered (gdb_stdlog, "<NULL>");
1754 fprintf_unfiltered (gdb_stdlog, ") ");
1757 /* Only try to do the unwind once. */
1758 if (this_frame->prev_p)
1762 fprintf_unfiltered (gdb_stdlog, "-> ");
1763 fprint_frame (gdb_stdlog, this_frame->prev);
1764 fprintf_unfiltered (gdb_stdlog, " // cached \n");
1766 return this_frame->prev;
1768 this_frame->prev_p = 1;
1770 /* If any of the old frame initialization methods are around, use
1771 the legacy get_prev_frame() method. */
1772 if (legacy_frame_p (current_gdbarch))
1774 prev_frame = legacy_get_prev_frame (this_frame);
1778 /* Check that this frame's ID was valid. If it wasn't, don't try to
1779 unwind to the prev frame. Be careful to not apply this test to
1780 the sentinel frame. */
1781 if (this_frame->level >= 0 && !frame_id_p (get_frame_id (this_frame)))
1785 fprintf_unfiltered (gdb_stdlog, "-> ");
1786 fprint_frame (gdb_stdlog, NULL);
1787 fprintf_unfiltered (gdb_stdlog, " // this ID is NULL }\n");
1792 /* Check that this frame's ID isn't inner to (younger, below, next)
1793 the next frame. This happens when a frame unwind goes backwards.
1794 Exclude signal trampolines (due to sigaltstack the frame ID can
1795 go backwards) and sentinel frames (the test is meaningless). */
1796 if (this_frame->next->level >= 0
1797 && this_frame->next->type != SIGTRAMP_FRAME
1798 && frame_id_inner (get_frame_id (this_frame),
1799 get_frame_id (this_frame->next)))
1800 error ("Previous frame inner to this frame (corrupt stack?)");
1802 /* Check that this and the next frame are not identical. If they
1803 are, there is most likely a stack cycle. As with the inner-than
1804 test above, avoid comparing the inner-most and sentinel frames. */
1805 if (this_frame->level > 0
1806 && frame_id_eq (get_frame_id (this_frame),
1807 get_frame_id (this_frame->next)))
1808 error ("Previous frame identical to this frame (corrupt stack?)");
1810 /* Allocate the new frame but do not wire it in to the frame chain.
1811 Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
1812 frame->next to pull some fancy tricks (of course such code is, by
1813 definition, recursive). Try to prevent it.
1815 There is no reason to worry about memory leaks, should the
1816 remainder of the function fail. The allocated memory will be
1817 quickly reclaimed when the frame cache is flushed, and the `we've
1818 been here before' check above will stop repeated memory
1819 allocation calls. */
1820 prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
1821 prev_frame->level = this_frame->level + 1;
1823 /* Don't yet compute ->unwind (and hence ->type). It is computed
1824 on-demand in get_frame_type, frame_register_unwind, and
1827 /* Don't yet compute the frame's ID. It is computed on-demand by
1830 /* The unwound frame ID is validate at the start of this function,
1831 as part of the logic to decide if that frame should be further
1832 unwound, and not here while the prev frame is being created.
1833 Doing this makes it possible for the user to examine a frame that
1834 has an invalid frame ID.
1836 Some very old VAX code noted: [...] For the sake of argument,
1837 suppose that the stack is somewhat trashed (which is one reason
1838 that "info frame" exists). So, return 0 (indicating we don't
1839 know the address of the arglist) if we don't know what frame this
1843 this_frame->prev = prev_frame;
1844 prev_frame->next = this_frame;
1848 fprintf_unfiltered (gdb_stdlog, "-> ");
1849 fprint_frame (gdb_stdlog, prev_frame);
1850 fprintf_unfiltered (gdb_stdlog, " }\n");
1856 /* Debug routine to print a NULL frame being returned. */
1859 frame_debug_got_null_frame (struct ui_file *file,
1860 struct frame_info *this_frame,
1865 fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame (this_frame=");
1866 if (this_frame != NULL)
1867 fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level);
1869 fprintf_unfiltered (gdb_stdlog, "<NULL>");
1870 fprintf_unfiltered (gdb_stdlog, ") -> // %s}\n", reason);
1874 /* Return a structure containing various interesting information about
1875 the frame that called THIS_FRAME. Returns NULL if there is entier
1876 no such frame or the frame fails any of a set of target-independent
1877 condition that should terminate the frame chain (e.g., as unwinding
1880 This function should not contain target-dependent tests, such as
1881 checking whether the program-counter is zero. */
1884 get_prev_frame (struct frame_info *this_frame)
1886 struct frame_info *prev_frame;
1888 /* Return the inner-most frame, when the caller passes in NULL. */
1889 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
1890 caller should have previously obtained a valid frame using
1891 get_selected_frame() and then called this code - only possibility
1892 I can think of is code behaving badly.
1894 NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
1895 block_innermost_frame(). It does the sequence: frame = NULL;
1896 while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
1897 it couldn't be written better, I don't know.
1899 NOTE: cagney/2003-01-11: I suspect what is happening in
1900 block_innermost_frame() is, when the target has no state
1901 (registers, memory, ...), it is still calling this function. The
1902 assumption being that this function will return NULL indicating
1903 that a frame isn't possible, rather than checking that the target
1904 has state and then calling get_current_frame() and
1905 get_prev_frame(). This is a guess mind. */
1906 if (this_frame == NULL)
1908 /* NOTE: cagney/2002-11-09: There was a code segment here that
1909 would error out when CURRENT_FRAME was NULL. The comment
1910 that went with it made the claim ...
1912 ``This screws value_of_variable, which just wants a nice
1913 clean NULL return from block_innermost_frame if there are no
1914 frames. I don't think I've ever seen this message happen
1915 otherwise. And returning NULL here is a perfectly legitimate
1918 Per the above, this code shouldn't even be called with a NULL
1920 frame_debug_got_null_frame (gdb_stdlog, this_frame, "this_frame NULL");
1921 return current_frame;
1924 /* There is always a frame. If this assertion fails, suspect that
1925 something should be calling get_selected_frame() or
1926 get_current_frame(). */
1927 gdb_assert (this_frame != NULL);
1929 /* Make sure we pass an address within THIS_FRAME's code block to
1930 inside_main_func(). Otherwise, we might stop unwinding at a
1931 function which has a call instruction as its last instruction if
1932 that function immediately precedes main(). */
1933 if (this_frame->level >= 0
1934 && !backtrace_past_main
1935 && inside_main_func (get_frame_address_in_block (this_frame)))
1936 /* Don't unwind past main(), but always unwind the sentinel frame.
1937 Note, this is done _before_ the frame has been marked as
1938 previously unwound. That way if the user later decides to
1939 allow unwinds past main(), that just happens. */
1941 frame_debug_got_null_frame (gdb_stdlog, this_frame, "inside main func");
1945 if (this_frame->level > backtrace_limit)
1947 error ("Backtrace limit of %d exceeded", backtrace_limit);
1950 /* If we're already inside the entry function for the main objfile,
1951 then it isn't valid. Don't apply this test to a dummy frame -
1952 dummy frame PCs typically land in the entry func. Don't apply
1953 this test to the sentinel frame. Sentinel frames should always
1954 be allowed to unwind. */
1955 /* NOTE: cagney/2003-02-25: Don't enable until someone has found
1956 hard evidence that this is needed. */
1957 /* NOTE: cagney/2003-07-07: Fixed a bug in inside_main_func() -
1958 wasn't checking for "main" in the minimal symbols. With that
1959 fixed asm-source tests now stop in "main" instead of halting the
1960 backtrace in weird and wonderful ways somewhere inside the entry
1961 file. Suspect that tests for inside the entry file/func were
1962 added to work around that (now fixed) case. */
1963 /* NOTE: cagney/2003-07-15: danielj (if I'm reading it right)
1964 suggested having the inside_entry_func test use the
1965 inside_main_func() msymbol trick (along with entry_point_address()
1966 I guess) to determine the address range of the start function.
1967 That should provide a far better stopper than the current
1969 /* NOTE: cagney/2003-07-15: Need to add a "set backtrace
1970 beyond-entry-func" command so that this can be selectively
1974 && backtrace_beyond_entry_func
1976 && this_frame->type != DUMMY_FRAME && this_frame->level >= 0
1977 && inside_entry_func (this_frame))
1979 frame_debug_got_null_frame (gdb_stdlog, this_frame, "inside entry func");
1983 return get_prev_frame_1 (this_frame);
1987 get_frame_pc (struct frame_info *frame)
1989 gdb_assert (frame->next != NULL);
1990 return frame_pc_unwind (frame->next);
1993 /* Return an address of that falls within the frame's code block. */
1996 frame_unwind_address_in_block (struct frame_info *next_frame)
1998 /* A draft address. */
1999 CORE_ADDR pc = frame_pc_unwind (next_frame);
2001 /* If THIS frame is not inner most (i.e., NEXT isn't the sentinel),
2002 and NEXT is `normal' (i.e., not a sigtramp, dummy, ....) THIS
2003 frame's PC ends up pointing at the instruction fallowing the
2004 "call". Adjust that PC value so that it falls on the call
2005 instruction (which, hopefully, falls within THIS frame's code
2006 block. So far it's proved to be a very good approximation. See
2007 get_frame_type() for why ->type can't be used. */
2008 if (next_frame->level >= 0
2009 && get_frame_type (next_frame) == NORMAL_FRAME)
2015 get_frame_address_in_block (struct frame_info *this_frame)
2017 return frame_unwind_address_in_block (this_frame->next);
2021 pc_notcurrent (struct frame_info *frame)
2023 /* If FRAME is not the innermost frame, that normally means that
2024 FRAME->pc points at the return instruction (which is *after* the
2025 call instruction), and we want to get the line containing the
2026 call (because the call is where the user thinks the program is).
2027 However, if the next frame is either a SIGTRAMP_FRAME or a
2028 DUMMY_FRAME, then the next frame will contain a saved interrupt
2029 PC and such a PC indicates the current (rather than next)
2030 instruction/line, consequently, for such cases, want to get the
2031 line containing fi->pc. */
2032 struct frame_info *next = get_next_frame (frame);
2033 int notcurrent = (next != NULL && get_frame_type (next) == NORMAL_FRAME);
2038 find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal)
2040 (*sal) = find_pc_line (get_frame_pc (frame), pc_notcurrent (frame));
2043 /* Per "frame.h", return the ``address'' of the frame. Code should
2044 really be using get_frame_id(). */
2046 get_frame_base (struct frame_info *fi)
2048 return get_frame_id (fi).stack_addr;
2051 /* High-level offsets into the frame. Used by the debug info. */
2054 get_frame_base_address (struct frame_info *fi)
2056 if (get_frame_type (fi) != NORMAL_FRAME)
2058 if (fi->base == NULL)
2059 fi->base = frame_base_find_by_frame (fi->next);
2060 /* Sneaky: If the low-level unwind and high-level base code share a
2061 common unwinder, let them share the prologue cache. */
2062 if (fi->base->unwind == fi->unwind)
2063 return fi->base->this_base (fi->next, &fi->prologue_cache);
2064 return fi->base->this_base (fi->next, &fi->base_cache);
2068 get_frame_locals_address (struct frame_info *fi)
2071 if (get_frame_type (fi) != NORMAL_FRAME)
2073 /* If there isn't a frame address method, find it. */
2074 if (fi->base == NULL)
2075 fi->base = frame_base_find_by_frame (fi->next);
2076 /* Sneaky: If the low-level unwind and high-level base code share a
2077 common unwinder, let them share the prologue cache. */
2078 if (fi->base->unwind == fi->unwind)
2079 cache = &fi->prologue_cache;
2081 cache = &fi->base_cache;
2082 return fi->base->this_locals (fi->next, cache);
2086 get_frame_args_address (struct frame_info *fi)
2089 if (get_frame_type (fi) != NORMAL_FRAME)
2091 /* If there isn't a frame address method, find it. */
2092 if (fi->base == NULL)
2093 fi->base = frame_base_find_by_frame (fi->next);
2094 /* Sneaky: If the low-level unwind and high-level base code share a
2095 common unwinder, let them share the prologue cache. */
2096 if (fi->base->unwind == fi->unwind)
2097 cache = &fi->prologue_cache;
2099 cache = &fi->base_cache;
2100 return fi->base->this_args (fi->next, cache);
2103 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
2104 or -1 for a NULL frame. */
2107 frame_relative_level (struct frame_info *fi)
2116 get_frame_type (struct frame_info *frame)
2118 /* Some targets still don't use [generic] dummy frames. Catch them
2120 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
2121 && deprecated_frame_in_dummy (frame))
2124 /* Some legacy code, e.g, mips_init_extra_frame_info() wants
2125 to determine the frame's type prior to it being completely
2126 initialized. Don't attempt to lazily initialize ->unwind for
2127 legacy code. It will be initialized in legacy_get_prev_frame(). */
2128 if (frame->unwind == NULL && !legacy_frame_p (current_gdbarch))
2130 /* Initialize the frame's unwinder because that's what
2131 provides the frame's type. */
2132 frame->unwind = frame_unwind_find_by_frame (frame->next,
2133 &frame->prologue_cache);
2134 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
2135 type in the frame, the unwinder's type should be returned
2136 directly. Unfortunately, legacy code, called by
2137 legacy_get_prev_frame(), explicitly set the frames type using
2138 the method deprecated_set_frame_type(). */
2139 frame->type = frame->unwind->type;
2141 if (frame->type == UNKNOWN_FRAME)
2142 return NORMAL_FRAME;
2148 deprecated_set_frame_type (struct frame_info *frame, enum frame_type type)
2150 /* Arrrg! See comment in "frame.h". */
2154 struct frame_extra_info *
2155 get_frame_extra_info (struct frame_info *fi)
2157 return fi->extra_info;
2160 struct frame_extra_info *
2161 frame_extra_info_zalloc (struct frame_info *fi, long size)
2163 fi->extra_info = frame_obstack_zalloc (size);
2164 return fi->extra_info;
2168 deprecated_update_frame_pc_hack (struct frame_info *frame, CORE_ADDR pc)
2171 fprintf_unfiltered (gdb_stdlog,
2172 "{ deprecated_update_frame_pc_hack (frame=%d,pc=0x%s) }\n",
2173 frame->level, paddr_nz (pc));
2174 /* NOTE: cagney/2003-03-11: Some architectures (e.g., Arm) are
2175 maintaining a locally allocated frame object. Since such frames
2176 are not in the frame chain, it isn't possible to assume that the
2177 frame has a next. Sigh. */
2178 if (frame->next != NULL)
2180 /* While we're at it, update this frame's cached PC value, found
2181 in the next frame. Oh for the day when "struct frame_info"
2182 is opaque and this hack on hack can just go away. */
2183 frame->next->prev_pc.value = pc;
2184 frame->next->prev_pc.p = 1;
2189 deprecated_update_frame_base_hack (struct frame_info *frame, CORE_ADDR base)
2192 fprintf_unfiltered (gdb_stdlog,
2193 "{ deprecated_update_frame_base_hack (frame=%d,base=0x%s) }\n",
2194 frame->level, paddr_nz (base));
2195 /* See comment in "frame.h". */
2196 frame->this_id.value.stack_addr = base;
2200 deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs,
2201 long sizeof_extra_info)
2203 struct frame_info *frame = XMALLOC (struct frame_info);
2204 memset (frame, 0, sizeof (*frame));
2205 frame->this_id.p = 1;
2206 make_cleanup (xfree, frame);
2207 if (sizeof_saved_regs > 0)
2209 frame->saved_regs = xcalloc (1, sizeof_saved_regs);
2210 make_cleanup (xfree, frame->saved_regs);
2212 if (sizeof_extra_info > 0)
2214 frame->extra_info = xcalloc (1, sizeof_extra_info);
2215 make_cleanup (xfree, frame->extra_info);
2220 /* Memory access methods. */
2223 get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr, void *buf,
2226 read_memory (addr, buf, len);
2230 get_frame_memory_signed (struct frame_info *this_frame, CORE_ADDR addr,
2233 return read_memory_integer (addr, len);
2237 get_frame_memory_unsigned (struct frame_info *this_frame, CORE_ADDR addr,
2240 return read_memory_unsigned_integer (addr, len);
2244 safe_frame_unwind_memory (struct frame_info *this_frame,
2245 CORE_ADDR addr, void *buf, int len)
2247 /* NOTE: read_memory_nobpt returns zero on success! */
2248 return !read_memory_nobpt (addr, buf, len);
2251 /* Architecture method. */
2254 get_frame_arch (struct frame_info *this_frame)
2256 return current_gdbarch;
2259 /* Stack pointer methods. */
2262 get_frame_sp (struct frame_info *this_frame)
2264 return frame_sp_unwind (this_frame->next);
2268 frame_sp_unwind (struct frame_info *next_frame)
2270 /* Normality - an architecture that provides a way of obtaining any
2271 frame inner-most address. */
2272 if (gdbarch_unwind_sp_p (current_gdbarch))
2273 return gdbarch_unwind_sp (current_gdbarch, next_frame);
2274 /* Things are looking grim. If it's the inner-most frame and there
2275 is a TARGET_READ_SP, then that can be used. */
2276 if (next_frame->level < 0 && TARGET_READ_SP_P ())
2277 return TARGET_READ_SP ();
2278 /* Now things are really are grim. Hope that the value returned by
2279 the SP_REGNUM register is meaningful. */
2283 frame_unwind_unsigned_register (next_frame, SP_REGNUM, &sp);
2286 internal_error (__FILE__, __LINE__, "Missing unwind SP method");
2291 legacy_frame_p (struct gdbarch *current_gdbarch)
2293 if (DEPRECATED_INIT_FRAME_PC_P ()
2294 || DEPRECATED_INIT_EXTRA_FRAME_INFO_P ()
2295 || DEPRECATED_FRAME_CHAIN_P ())
2296 /* No question, it's a legacy frame. */
2298 if (gdbarch_unwind_dummy_id_p (current_gdbarch))
2299 /* No question, it's not a legacy frame (provided none of the
2300 deprecated methods checked above are present that is). */
2302 if (DEPRECATED_TARGET_READ_FP_P ()
2303 || DEPRECATED_FP_REGNUM >= 0)
2304 /* Assume it's legacy. If you're trying to convert a legacy frame
2305 target to the new mechanism, get rid of these. legacy
2306 get_prev_frame() requires these when unwind_frame_id() isn't
2309 /* Default to assuming that it's brand new code, and hence not
2310 legacy. Force it down the non-legacy path so that the new code
2311 uses the new frame mechanism from day one. Dummy frames won't
2312 work very well but we can live with that. */
2316 extern initialize_file_ftype _initialize_frame; /* -Wmissing-prototypes */
2318 static struct cmd_list_element *set_backtrace_cmdlist;
2319 static struct cmd_list_element *show_backtrace_cmdlist;
2322 set_backtrace_cmd (char *args, int from_tty)
2324 help_list (set_backtrace_cmdlist, "set backtrace ", -1, gdb_stdout);
2328 show_backtrace_cmd (char *args, int from_tty)
2330 cmd_show_list (show_backtrace_cmdlist, from_tty, "");
2334 _initialize_frame (void)
2336 obstack_init (&frame_cache_obstack);
2338 observer_attach_target_changed (frame_observer_target_changed);
2340 add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, "\
2341 Set backtrace specific variables.\n\
2342 Configure backtrace variables such as the backtrace limit",
2343 &set_backtrace_cmdlist, "set backtrace ",
2344 0/*allow-unknown*/, &setlist);
2345 add_prefix_cmd ("backtrace", class_maintenance, show_backtrace_cmd, "\
2346 Show backtrace specific variables\n\
2347 Show backtrace variables such as the backtrace limit",
2348 &show_backtrace_cmdlist, "show backtrace ",
2349 0/*allow-unknown*/, &showlist);
2351 add_setshow_boolean_cmd ("past-main", class_obscure,
2352 &backtrace_past_main, "\
2353 Set whether backtraces should continue past \"main\".\n\
2354 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2355 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2356 of the stack trace.", "\
2357 Show whether backtraces should continue past \"main\".\n\
2358 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2359 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2360 of the stack trace.",
2361 NULL, NULL, &set_backtrace_cmdlist,
2362 &show_backtrace_cmdlist);
2364 add_setshow_uinteger_cmd ("limit", class_obscure,
2365 &backtrace_limit, "\
2366 Set an upper bound on the number of backtrace levels.\n\
2367 No more than the specified number of frames can be displayed or examined.\n\
2368 Zero is unlimited.", "\
2369 Show the upper bound on the number of backtrace levels.",
2370 NULL, NULL, &set_backtrace_cmdlist,
2371 &show_backtrace_cmdlist);
2373 /* Debug this files internals. */
2374 add_show_from_set (add_set_cmd ("frame", class_maintenance, var_zinteger,
2375 &frame_debug, "Set frame debugging.\n\
2376 When non-zero, frame specific internal debugging is enabled.", &setdebuglist),