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 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"
43 /* We keep a cache of stack frames, each of which is a "struct
44 frame_info". The innermost one gets allocated (in
45 wait_for_inferior) each time the inferior stops; current_frame
46 points to it. Additional frames get allocated (in get_prev_frame)
47 as needed, and are chained through the next and prev fields. Any
48 time that the frame cache becomes invalid (most notably when we
49 execute something, but also if we change how we interpret the
50 frames (e.g. "set heuristic-fence-post" in mips-tdep.c, or anything
51 which reads new symbols)), we should call reinit_frame_cache. */
55 /* Level of this frame. The inner-most (youngest) frame is at level
56 0. As you move towards the outer-most (oldest) frame, the level
57 increases. This is a cached value. It could just as easily be
58 computed by counting back from the selected frame to the inner
60 /* NOTE: cagney/2002-04-05: Perhaphs a level of ``-1'' should be
61 reserved to indicate a bogus frame - one that has been created
62 just to keep GDB happy (GDB always needs a frame). For the
63 moment leave this as speculation. */
66 /* The frame's type. */
67 /* FIXME: cagney/2003-04-02: Should instead be returning
68 ->unwind->type. Unfortunately, legacy code is still explicitly
69 setting the type using the method deprecated_set_frame_type.
70 Eliminate that method and this field can be eliminated. */
73 /* For each register, address of where it was saved on entry to the
74 frame, or zero if it was not saved on entry to this frame. This
75 includes special registers such as pc and fp saved in special
76 ways in the stack frame. The SP_REGNUM is even more special, the
77 address here is the sp for the previous frame, not the address
78 where the sp was saved. */
79 /* Allocated by frame_saved_regs_zalloc () which is called /
80 initialized by DEPRECATED_FRAME_INIT_SAVED_REGS(). */
81 CORE_ADDR
*saved_regs
; /*NUM_REGS + NUM_PSEUDO_REGS*/
83 /* Anything extra for this structure that may have been defined in
84 the machine dependent files. */
85 /* Allocated by frame_extra_info_zalloc () which is called /
86 initialized by DEPRECATED_INIT_EXTRA_FRAME_INFO */
87 struct frame_extra_info
*extra_info
;
89 /* The frame's low-level unwinder and corresponding cache. The
90 low-level unwinder is responsible for unwinding register values
91 for the previous frame. The low-level unwind methods are
92 selected based on the presence, or otherwize, of register unwind
93 information such as CFI. */
95 const struct frame_unwind
*unwind
;
97 /* Cached copy of the previous frame's resume address. */
103 /* Cached copy of the previous frame's function address. */
110 /* This frame's ID. */
114 struct frame_id value
;
117 /* The frame's high-level base methods, and corresponding cache.
118 The high level base methods are selected based on the frame's
120 const struct frame_base
*base
;
123 /* Pointers to the next (down, inner, younger) and previous (up,
124 outer, older) frame_info's in the frame cache. */
125 struct frame_info
*next
; /* down, inner, younger */
127 struct frame_info
*prev
; /* up, outer, older */
130 /* Flag to control debugging. */
132 static int frame_debug
;
134 /* Flag to indicate whether backtraces should stop at main et.al. */
136 static int backtrace_past_main
;
137 static unsigned int backtrace_limit
= UINT_MAX
;
141 fprint_frame_id (struct ui_file
*file
, struct frame_id id
)
143 fprintf_unfiltered (file
, "{stack=0x%s,code=0x%s,special=0x%s}",
144 paddr_nz (id
.stack_addr
),
145 paddr_nz (id
.code_addr
),
146 paddr_nz (id
.special_addr
));
150 fprint_frame_type (struct ui_file
*file
, enum frame_type type
)
155 fprintf_unfiltered (file
, "UNKNOWN_FRAME");
158 fprintf_unfiltered (file
, "NORMAL_FRAME");
161 fprintf_unfiltered (file
, "DUMMY_FRAME");
164 fprintf_unfiltered (file
, "SIGTRAMP_FRAME");
167 fprintf_unfiltered (file
, "<unknown type>");
173 fprint_frame (struct ui_file
*file
, struct frame_info
*fi
)
177 fprintf_unfiltered (file
, "<NULL frame>");
180 fprintf_unfiltered (file
, "{");
181 fprintf_unfiltered (file
, "level=%d", fi
->level
);
182 fprintf_unfiltered (file
, ",");
183 fprintf_unfiltered (file
, "type=");
184 fprint_frame_type (file
, fi
->type
);
185 fprintf_unfiltered (file
, ",");
186 fprintf_unfiltered (file
, "unwind=");
187 if (fi
->unwind
!= NULL
)
188 gdb_print_host_address (fi
->unwind
, file
);
190 fprintf_unfiltered (file
, "<unknown>");
191 fprintf_unfiltered (file
, ",");
192 fprintf_unfiltered (file
, "pc=");
193 if (fi
->next
!= NULL
&& fi
->next
->prev_pc
.p
)
194 fprintf_unfiltered (file
, "0x%s", paddr_nz (fi
->next
->prev_pc
.value
));
196 fprintf_unfiltered (file
, "<unknown>");
197 fprintf_unfiltered (file
, ",");
198 fprintf_unfiltered (file
, "id=");
200 fprint_frame_id (file
, fi
->this_id
.value
);
202 fprintf_unfiltered (file
, "<unknown>");
203 fprintf_unfiltered (file
, ",");
204 fprintf_unfiltered (file
, "func=");
205 if (fi
->next
!= NULL
&& fi
->next
->prev_func
.p
)
206 fprintf_unfiltered (file
, "0x%s", paddr_nz (fi
->next
->prev_func
.addr
));
208 fprintf_unfiltered (file
, "<unknown>");
209 fprintf_unfiltered (file
, "}");
212 /* Return a frame uniq ID that can be used to, later, re-find the
216 get_frame_id (struct frame_info
*fi
)
220 return null_frame_id
;
224 gdb_assert (!legacy_frame_p (current_gdbarch
));
226 fprintf_unfiltered (gdb_stdlog
, "{ get_frame_id (fi=%d) ",
228 /* Find the unwinder. */
229 if (fi
->unwind
== NULL
)
231 fi
->unwind
= frame_unwind_find_by_frame (fi
->next
);
232 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
233 type in the frame, the unwinder's type should be returned
234 directly. Unfortunately, legacy code, called by
235 legacy_get_prev_frame, explicitly set the frames type
236 using the method deprecated_set_frame_type(). */
237 gdb_assert (fi
->unwind
->type
!= UNKNOWN_FRAME
);
238 fi
->type
= fi
->unwind
->type
;
240 /* Find THIS frame's ID. */
241 fi
->unwind
->this_id (fi
->next
, &fi
->prologue_cache
, &fi
->this_id
.value
);
245 fprintf_unfiltered (gdb_stdlog
, "-> ");
246 fprint_frame_id (gdb_stdlog
, fi
->this_id
.value
);
247 fprintf_unfiltered (gdb_stdlog
, " }\n");
250 return fi
->this_id
.value
;
253 const struct frame_id null_frame_id
; /* All zeros. */
256 frame_id_build_special (CORE_ADDR stack_addr
, CORE_ADDR code_addr
,
257 CORE_ADDR special_addr
)
260 id
.stack_addr
= stack_addr
;
261 id
.code_addr
= code_addr
;
262 id
.special_addr
= special_addr
;
267 frame_id_build (CORE_ADDR stack_addr
, CORE_ADDR code_addr
)
269 return frame_id_build_special (stack_addr
, code_addr
, 0);
273 frame_id_p (struct frame_id l
)
276 /* The .code can be NULL but the .stack cannot. */
277 p
= (l
.stack_addr
!= 0);
280 fprintf_unfiltered (gdb_stdlog
, "{ frame_id_p (l=");
281 fprint_frame_id (gdb_stdlog
, l
);
282 fprintf_unfiltered (gdb_stdlog
, ") -> %d }\n", p
);
288 frame_id_eq (struct frame_id l
, struct frame_id r
)
291 if (l
.stack_addr
== 0 || r
.stack_addr
== 0)
292 /* Like a NaN, if either ID is invalid, the result is false. */
294 else if (l
.stack_addr
!= r
.stack_addr
)
295 /* If .stack addresses are different, the frames are different. */
297 else if (l
.code_addr
== 0 || r
.code_addr
== 0)
298 /* A zero code addr is a wild card, always succeed. */
300 else if (l
.code_addr
!= r
.code_addr
)
301 /* If .code addresses are different, the frames are different. */
303 else if (l
.special_addr
== 0 || r
.special_addr
== 0)
304 /* A zero special addr is a wild card (or unused), always succeed. */
306 else if (l
.special_addr
== r
.special_addr
)
307 /* Frames are equal. */
314 fprintf_unfiltered (gdb_stdlog
, "{ frame_id_eq (l=");
315 fprint_frame_id (gdb_stdlog
, l
);
316 fprintf_unfiltered (gdb_stdlog
, ",r=");
317 fprint_frame_id (gdb_stdlog
, r
);
318 fprintf_unfiltered (gdb_stdlog
, ") -> %d }\n", eq
);
324 frame_id_inner (struct frame_id l
, struct frame_id r
)
327 if (l
.stack_addr
== 0 || r
.stack_addr
== 0)
328 /* Like NaN, any operation involving an invalid ID always fails. */
331 /* Only return non-zero when strictly inner than. Note that, per
332 comment in "frame.h", there is some fuzz here. Frameless
333 functions are not strictly inner than (same .stack but
334 different .code and/or .special address). */
335 inner
= INNER_THAN (l
.stack_addr
, r
.stack_addr
);
338 fprintf_unfiltered (gdb_stdlog
, "{ frame_id_inner (l=");
339 fprint_frame_id (gdb_stdlog
, l
);
340 fprintf_unfiltered (gdb_stdlog
, ",r=");
341 fprint_frame_id (gdb_stdlog
, r
);
342 fprintf_unfiltered (gdb_stdlog
, ") -> %d }\n", inner
);
348 frame_find_by_id (struct frame_id id
)
350 struct frame_info
*frame
;
352 /* ZERO denotes the null frame, let the caller decide what to do
353 about it. Should it instead return get_current_frame()? */
354 if (!frame_id_p (id
))
357 for (frame
= get_current_frame ();
359 frame
= get_prev_frame (frame
))
361 struct frame_id
this = get_frame_id (frame
);
362 if (frame_id_eq (id
, this))
363 /* An exact match. */
365 if (frame_id_inner (id
, this))
368 /* Either, we're not yet gone far enough out along the frame
369 chain (inner(this,id), or we're comparing frameless functions
370 (same .base, different .func, no test available). Struggle
371 on until we've definitly gone to far. */
377 frame_pc_unwind (struct frame_info
*this_frame
)
379 if (!this_frame
->prev_pc
.p
)
382 if (gdbarch_unwind_pc_p (current_gdbarch
))
384 /* The right way. The `pure' way. The one true way. This
385 method depends solely on the register-unwind code to
386 determine the value of registers in THIS frame, and hence
387 the value of this frame's PC (resume address). A typical
388 implementation is no more than:
390 frame_unwind_register (this_frame, ISA_PC_REGNUM, buf);
391 return extract_unsigned_integer (buf, size of ISA_PC_REGNUM);
393 Note: this method is very heavily dependent on a correct
394 register-unwind implementation, it pays to fix that
395 method first; this method is frame type agnostic, since
396 it only deals with register values, it works with any
397 frame. This is all in stark contrast to the old
398 FRAME_SAVED_PC which would try to directly handle all the
399 different ways that a PC could be unwound. */
400 pc
= gdbarch_unwind_pc (current_gdbarch
, this_frame
);
402 else if (this_frame
->level
< 0)
404 /* FIXME: cagney/2003-03-06: Old code and and a sentinel
405 frame. Do like was always done. Fetch the PC's value
406 direct from the global registers array (via read_pc).
407 This assumes that this frame belongs to the current
408 global register cache. The assumption is dangerous. */
411 else if (DEPRECATED_FRAME_SAVED_PC_P ())
413 /* FIXME: cagney/2003-03-06: Old code, but not a sentinel
414 frame. Do like was always done. Note that this method,
415 unlike unwind_pc(), tries to handle all the different
416 frame cases directly. It fails. */
417 pc
= DEPRECATED_FRAME_SAVED_PC (this_frame
);
420 internal_error (__FILE__
, __LINE__
, "No gdbarch_unwind_pc method");
421 this_frame
->prev_pc
.value
= pc
;
422 this_frame
->prev_pc
.p
= 1;
424 fprintf_unfiltered (gdb_stdlog
,
425 "{ frame_pc_unwind (this_frame=%d) -> 0x%s }\n",
427 paddr_nz (this_frame
->prev_pc
.value
));
429 return this_frame
->prev_pc
.value
;
433 frame_func_unwind (struct frame_info
*fi
)
435 if (!fi
->prev_func
.p
)
437 /* Make certain that this, and not the adjacent, function is
439 CORE_ADDR addr_in_block
= frame_unwind_address_in_block (fi
);
441 fi
->prev_func
.addr
= get_pc_function_start (addr_in_block
);
443 fprintf_unfiltered (gdb_stdlog
,
444 "{ frame_func_unwind (fi=%d) -> 0x%s }\n",
445 fi
->level
, paddr_nz (fi
->prev_func
.addr
));
447 return fi
->prev_func
.addr
;
451 get_frame_func (struct frame_info
*fi
)
453 return frame_func_unwind (fi
->next
);
457 do_frame_unwind_register (void *src
, int regnum
, void *buf
)
459 frame_unwind_register (src
, regnum
, buf
);
464 frame_pop (struct frame_info
*this_frame
)
466 struct regcache
*scratch_regcache
;
467 struct cleanup
*cleanups
;
469 if (DEPRECATED_POP_FRAME_P ())
471 /* A legacy architecture that has implemented a custom pop
472 function. All new architectures should instead be using the
473 generic code below. */
474 DEPRECATED_POP_FRAME
;
478 /* Make a copy of all the register values unwound from this
479 frame. Save them in a scratch buffer so that there isn't a
480 race betweening trying to extract the old values from the
481 current_regcache while, at the same time writing new values
482 into that same cache. */
483 struct regcache
*scratch
= regcache_xmalloc (current_gdbarch
);
484 struct cleanup
*cleanups
= make_cleanup_regcache_xfree (scratch
);
485 regcache_save (scratch
, do_frame_unwind_register
, this_frame
);
486 /* FIXME: cagney/2003-03-16: It should be possible to tell the
487 target's register cache that it is about to be hit with a
488 burst register transfer and that the sequence of register
489 writes should be batched. The pair target_prepare_to_store()
490 and target_store_registers() kind of suggest this
491 functionality. Unfortunately, they don't implement it. Their
492 lack of a formal definition can lead to targets writing back
493 bogus values (arguably a bug in the target code mind). */
494 /* Now copy those saved registers into the current regcache.
495 Here, regcache_cpy() calls regcache_restore(). */
496 regcache_cpy (current_regcache
, scratch
);
497 do_cleanups (cleanups
);
499 /* We've made right mess of GDB's local state, just discard
501 flush_cached_frames ();
505 frame_register_unwind (struct frame_info
*frame
, int regnum
,
506 int *optimizedp
, enum lval_type
*lvalp
,
507 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
509 struct frame_unwind_cache
*cache
;
513 fprintf_unfiltered (gdb_stdlog
,
514 "{ frame_register_unwind (frame=%d,regnum=\"%s\",...) ",
515 frame
->level
, frame_map_regnum_to_name (frame
, regnum
));
518 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
519 that the value proper does not need to be fetched. */
520 gdb_assert (optimizedp
!= NULL
);
521 gdb_assert (lvalp
!= NULL
);
522 gdb_assert (addrp
!= NULL
);
523 gdb_assert (realnump
!= NULL
);
524 /* gdb_assert (bufferp != NULL); */
526 /* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame
527 is broken. There is always a frame. If there, for some reason,
528 isn't, there is some pretty busted code as it should have
529 detected the problem before calling here. */
530 gdb_assert (frame
!= NULL
);
532 /* Find the unwinder. */
533 if (frame
->unwind
== NULL
)
535 frame
->unwind
= frame_unwind_find_by_frame (frame
->next
);
536 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
537 type in the frame, the unwinder's type should be returned
538 directly. Unfortunately, legacy code, called by
539 legacy_get_prev_frame, explicitly set the frames type using
540 the method deprecated_set_frame_type(). */
541 gdb_assert (frame
->unwind
->type
!= UNKNOWN_FRAME
);
542 frame
->type
= frame
->unwind
->type
;
545 /* Ask this frame to unwind its register. See comment in
546 "frame-unwind.h" for why NEXT frame and this unwind cace are
548 frame
->unwind
->prev_register (frame
->next
, &frame
->prologue_cache
, regnum
,
549 optimizedp
, lvalp
, addrp
, realnump
, bufferp
);
553 fprintf_unfiltered (gdb_stdlog
, "->");
554 fprintf_unfiltered (gdb_stdlog
, " *optimizedp=%d", (*optimizedp
));
555 fprintf_unfiltered (gdb_stdlog
, " *lvalp=%d", (int) (*lvalp
));
556 fprintf_unfiltered (gdb_stdlog
, " *addrp=0x%s", paddr_nz ((*addrp
)));
557 fprintf_unfiltered (gdb_stdlog
, " *bufferp=");
559 fprintf_unfiltered (gdb_stdlog
, "<NULL>");
563 const unsigned char *buf
= bufferp
;
564 fprintf_unfiltered (gdb_stdlog
, "[");
565 for (i
= 0; i
< register_size (current_gdbarch
, regnum
); i
++)
566 fprintf_unfiltered (gdb_stdlog
, "%02x", buf
[i
]);
567 fprintf_unfiltered (gdb_stdlog
, "]");
569 fprintf_unfiltered (gdb_stdlog
, " }\n");
574 frame_register (struct frame_info
*frame
, int regnum
,
575 int *optimizedp
, enum lval_type
*lvalp
,
576 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
578 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
579 that the value proper does not need to be fetched. */
580 gdb_assert (optimizedp
!= NULL
);
581 gdb_assert (lvalp
!= NULL
);
582 gdb_assert (addrp
!= NULL
);
583 gdb_assert (realnump
!= NULL
);
584 /* gdb_assert (bufferp != NULL); */
586 /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
587 of the register in the register cache. It should instead return
588 the REGNUM corresponding to that register. Translate the . */
589 if (DEPRECATED_GET_SAVED_REGISTER_P ())
591 DEPRECATED_GET_SAVED_REGISTER (bufferp
, optimizedp
, addrp
, frame
,
593 /* Compute the REALNUM if the caller wants it. */
594 if (*lvalp
== lval_register
)
597 for (regnum
= 0; regnum
< NUM_REGS
+ NUM_PSEUDO_REGS
; regnum
++)
599 if (*addrp
== register_offset_hack (current_gdbarch
, regnum
))
605 internal_error (__FILE__
, __LINE__
,
606 "Failed to compute the register number corresponding"
607 " to 0x%s", paddr_d (*addrp
));
613 /* Obtain the register value by unwinding the register from the next
614 (more inner frame). */
615 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
616 frame_register_unwind (frame
->next
, regnum
, optimizedp
, lvalp
, addrp
,
621 frame_unwind_register (struct frame_info
*frame
, int regnum
, void *buf
)
627 frame_register_unwind (frame
, regnum
, &optimized
, &lval
, &addr
,
632 get_frame_register (struct frame_info
*frame
,
633 int regnum
, void *buf
)
635 frame_unwind_register (frame
->next
, regnum
, buf
);
639 frame_unwind_register_signed (struct frame_info
*frame
, int regnum
)
641 char buf
[MAX_REGISTER_SIZE
];
642 frame_unwind_register (frame
, regnum
, buf
);
643 return extract_signed_integer (buf
, DEPRECATED_REGISTER_VIRTUAL_SIZE (regnum
));
647 get_frame_register_signed (struct frame_info
*frame
, int regnum
)
649 return frame_unwind_register_signed (frame
->next
, regnum
);
653 frame_unwind_register_unsigned (struct frame_info
*frame
, int regnum
)
655 char buf
[MAX_REGISTER_SIZE
];
656 frame_unwind_register (frame
, regnum
, buf
);
657 return extract_unsigned_integer (buf
, DEPRECATED_REGISTER_VIRTUAL_SIZE (regnum
));
661 get_frame_register_unsigned (struct frame_info
*frame
, int regnum
)
663 return frame_unwind_register_unsigned (frame
->next
, regnum
);
667 frame_unwind_unsigned_register (struct frame_info
*frame
, int regnum
,
670 char buf
[MAX_REGISTER_SIZE
];
671 frame_unwind_register (frame
, regnum
, buf
);
672 (*val
) = extract_unsigned_integer (buf
, DEPRECATED_REGISTER_VIRTUAL_SIZE (regnum
));
676 put_frame_register (struct frame_info
*frame
, int regnum
, const void *buf
)
678 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
683 frame_register (frame
, regnum
, &optim
, &lval
, &addr
, &realnum
, NULL
);
685 error ("Attempt to assign to a value that was optimized out.");
690 /* FIXME: write_memory doesn't yet take constant buffers.
692 char tmp
[MAX_REGISTER_SIZE
];
693 memcpy (tmp
, buf
, register_size (gdbarch
, regnum
));
694 write_memory (addr
, tmp
, register_size (gdbarch
, regnum
));
698 regcache_cooked_write (current_regcache
, realnum
, buf
);
701 error ("Attempt to assign to an unmodifiable value.");
705 /* frame_register_read ()
707 Find and return the value of REGNUM for the specified stack frame.
708 The number of bytes copied is DEPRECATED_REGISTER_RAW_SIZE
711 Returns 0 if the register value could not be found. */
714 frame_register_read (struct frame_info
*frame
, int regnum
, void *myaddr
)
720 frame_register (frame
, regnum
, &optimized
, &lval
, &addr
, &realnum
, myaddr
);
722 /* FIXME: cagney/2002-05-15: This test, is just bogus.
724 It indicates that the target failed to supply a value for a
725 register because it was "not available" at this time. Problem
726 is, the target still has the register and so get saved_register()
727 may be returning a value saved on the stack. */
729 if (register_cached (regnum
) < 0)
730 return 0; /* register value not available */
736 /* Map between a frame register number and its name. A frame register
737 space is a superset of the cooked register space --- it also
738 includes builtin registers. */
741 frame_map_name_to_regnum (struct frame_info
*frame
, const char *name
, int len
)
743 return user_reg_map_name_to_regnum (get_frame_arch (frame
), name
, len
);
747 frame_map_regnum_to_name (struct frame_info
*frame
, int regnum
)
749 return user_reg_map_regnum_to_name (get_frame_arch (frame
), regnum
);
752 /* Create a sentinel frame. */
754 static struct frame_info
*
755 create_sentinel_frame (struct regcache
*regcache
)
757 struct frame_info
*frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
758 frame
->type
= NORMAL_FRAME
;
760 /* Explicitly initialize the sentinel frame's cache. Provide it
761 with the underlying regcache. In the future additional
762 information, such as the frame's thread will be added. */
763 frame
->prologue_cache
= sentinel_frame_cache (regcache
);
764 /* For the moment there is only one sentinel frame implementation. */
765 frame
->unwind
= sentinel_frame_unwind
;
766 /* Link this frame back to itself. The frame is self referential
767 (the unwound PC is the same as the pc), so make it so. */
769 /* Make the sentinel frame's ID valid, but invalid. That way all
770 comparisons with it should fail. */
771 frame
->this_id
.p
= 1;
772 frame
->this_id
.value
= null_frame_id
;
775 fprintf_unfiltered (gdb_stdlog
, "{ create_sentinel_frame (...) -> ");
776 fprint_frame (gdb_stdlog
, frame
);
777 fprintf_unfiltered (gdb_stdlog
, " }\n");
782 /* Info about the innermost stack frame (contents of FP register) */
784 static struct frame_info
*current_frame
;
786 /* Cache for frame addresses already read by gdb. Valid only while
787 inferior is stopped. Control variables for the frame cache should
788 be local to this module. */
790 static struct obstack frame_cache_obstack
;
793 frame_obstack_zalloc (unsigned long size
)
795 void *data
= obstack_alloc (&frame_cache_obstack
, size
);
796 memset (data
, 0, size
);
801 frame_saved_regs_zalloc (struct frame_info
*fi
)
803 fi
->saved_regs
= (CORE_ADDR
*)
804 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
805 return fi
->saved_regs
;
809 deprecated_get_frame_saved_regs (struct frame_info
*fi
)
811 return fi
->saved_regs
;
814 /* Return the innermost (currently executing) stack frame. This is
815 split into two functions. The function unwind_to_current_frame()
816 is wrapped in catch exceptions so that, even when the unwind of the
817 sentinel frame fails, the function still returns a stack frame. */
820 unwind_to_current_frame (struct ui_out
*ui_out
, void *args
)
822 struct frame_info
*frame
= get_prev_frame (args
);
823 /* A sentinel frame can fail to unwind, eg, because it's PC value
824 lands in somewhere like start. */
827 current_frame
= frame
;
832 get_current_frame (void)
834 /* First check, and report, the lack of registers. Having GDB
835 report "No stack!" or "No memory" when the target doesn't even
836 have registers is very confusing. Besides, "printcmd.exp"
837 explicitly checks that ``print $pc'' with no registers prints "No
839 if (!target_has_registers
)
840 error ("No registers.");
841 if (!target_has_stack
)
843 if (!target_has_memory
)
844 error ("No memory.");
845 if (current_frame
== NULL
)
847 struct frame_info
*sentinel_frame
=
848 create_sentinel_frame (current_regcache
);
849 if (catch_exceptions (uiout
, unwind_to_current_frame
, sentinel_frame
,
850 NULL
, RETURN_MASK_ERROR
) != 0)
852 /* Oops! Fake a current frame? Is this useful? It has a PC
853 of zero, for instance. */
854 current_frame
= sentinel_frame
;
857 return current_frame
;
860 /* The "selected" stack frame is used by default for local and arg
861 access. May be zero, for no selected frame. */
863 struct frame_info
*deprecated_selected_frame
;
865 /* Return the selected frame. Always non-null (unless there isn't an
866 inferior sufficient for creating a frame) in which case an error is
870 get_selected_frame (void)
872 if (deprecated_selected_frame
== NULL
)
873 /* Hey! Don't trust this. It should really be re-finding the
874 last selected frame of the currently selected thread. This,
875 though, is better than nothing. */
876 select_frame (get_current_frame ());
877 /* There is always a frame. */
878 gdb_assert (deprecated_selected_frame
!= NULL
);
879 return deprecated_selected_frame
;
882 /* This is a variant of get_selected_frame which can be called when
883 the inferior does not have a frame; in that case it will return
884 NULL instead of calling error (). */
887 deprecated_safe_get_selected_frame (void)
889 if (!target_has_registers
|| !target_has_stack
|| !target_has_memory
)
891 return get_selected_frame ();
894 /* Select frame FI (or NULL - to invalidate the current frame). */
897 select_frame (struct frame_info
*fi
)
901 deprecated_selected_frame
= fi
;
902 /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
903 frame is being invalidated. */
904 if (selected_frame_level_changed_hook
)
905 selected_frame_level_changed_hook (frame_relative_level (fi
));
907 /* FIXME: kseitz/2002-08-28: It would be nice to call
908 selected_frame_level_changed_event right here, but due to limitations
909 in the current interfaces, we would end up flooding UIs with events
910 because select_frame is used extensively internally.
912 Once we have frame-parameterized frame (and frame-related) commands,
913 the event notification can be moved here, since this function will only
914 be called when the users selected frame is being changed. */
916 /* Ensure that symbols for this frame are read in. Also, determine the
917 source language of this frame, and switch to it if desired. */
920 s
= find_pc_symtab (get_frame_pc (fi
));
922 && s
->language
!= current_language
->la_language
923 && s
->language
!= language_unknown
924 && language_mode
== language_mode_auto
)
926 set_language (s
->language
);
931 /* Return the register saved in the simplistic ``saved_regs'' cache.
932 If the value isn't here AND a value is needed, try the next inner
936 legacy_saved_regs_prev_register (struct frame_info
*next_frame
,
937 void **this_prologue_cache
,
938 int regnum
, int *optimizedp
,
939 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
940 int *realnump
, void *bufferp
)
942 /* HACK: New code is passed the next frame and this cache.
943 Unfortunately, old code expects this frame. Since this is a
944 backward compatibility hack, cheat by walking one level along the
945 prologue chain to the frame the old code expects.
947 Do not try this at home. Professional driver, closed course. */
948 struct frame_info
*frame
= next_frame
->prev
;
949 gdb_assert (frame
!= NULL
);
951 if (deprecated_get_frame_saved_regs (frame
) == NULL
)
953 /* If nothing's initialized the saved regs, do it now. */
954 gdb_assert (DEPRECATED_FRAME_INIT_SAVED_REGS_P ());
955 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
956 gdb_assert (deprecated_get_frame_saved_regs (frame
) != NULL
);
959 if (deprecated_get_frame_saved_regs (frame
) != NULL
960 && deprecated_get_frame_saved_regs (frame
)[regnum
] != 0)
962 if (regnum
== SP_REGNUM
)
964 /* SP register treated specially. */
970 /* NOTE: cagney/2003-05-09: In-lined store_address with
971 it's body - store_unsigned_integer. */
972 store_unsigned_integer (bufferp
, DEPRECATED_REGISTER_RAW_SIZE (regnum
),
973 deprecated_get_frame_saved_regs (frame
)[regnum
]);
977 /* Any other register is saved in memory, fetch it but cache
978 a local copy of its value. */
980 *lvalp
= lval_memory
;
981 *addrp
= deprecated_get_frame_saved_regs (frame
)[regnum
];
986 /* Save each register value, as it is read in, in a
987 frame based cache. */
988 void **regs
= (*this_prologue_cache
);
991 int sizeof_cache
= ((NUM_REGS
+ NUM_PSEUDO_REGS
)
993 regs
= frame_obstack_zalloc (sizeof_cache
);
994 (*this_prologue_cache
) = regs
;
996 if (regs
[regnum
] == NULL
)
999 = frame_obstack_zalloc (DEPRECATED_REGISTER_RAW_SIZE (regnum
));
1000 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], regs
[regnum
],
1001 DEPRECATED_REGISTER_RAW_SIZE (regnum
));
1003 memcpy (bufferp
, regs
[regnum
], DEPRECATED_REGISTER_RAW_SIZE (regnum
));
1005 /* Read the value in from memory. */
1006 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], bufferp
,
1007 DEPRECATED_REGISTER_RAW_SIZE (regnum
));
1014 /* No luck. Assume this and the next frame have the same register
1015 value. Pass the unwind request down the frame chain to the next
1016 frame. Hopefully that frame will find the register's location. */
1017 frame_register_unwind (next_frame
, regnum
, optimizedp
, lvalp
, addrp
,
1022 legacy_saved_regs_this_id (struct frame_info
*next_frame
,
1023 void **this_prologue_cache
,
1024 struct frame_id
*id
)
1026 /* legacy_get_prev_frame() always sets ->this_id.p, hence this is
1028 internal_error (__FILE__
, __LINE__
, "legacy_saved_regs_this_id() called");
1031 const struct frame_unwind legacy_saved_regs_unwinder
= {
1032 /* Not really. It gets overridden by legacy_get_prev_frame. */
1034 legacy_saved_regs_this_id
,
1035 legacy_saved_regs_prev_register
1037 const struct frame_unwind
*legacy_saved_regs_unwind
= &legacy_saved_regs_unwinder
;
1040 /* Function: deprecated_generic_get_saved_register
1041 Find register number REGNUM relative to FRAME and put its (raw,
1042 target format) contents in *RAW_BUFFER.
1044 Set *OPTIMIZED if the variable was optimized out (and thus can't be
1045 fetched). Note that this is never set to anything other than zero
1046 in this implementation.
1048 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
1049 whether the value was fetched from memory, from a register, or in a
1050 strange and non-modifiable way (e.g. a frame pointer which was
1051 calculated rather than fetched). We will use not_lval for values
1052 fetched from generic dummy frames.
1054 Set *ADDRP to the address, either in memory or as a
1055 DEPRECATED_REGISTER_BYTE offset into the registers array. If the
1056 value is stored in a dummy frame, set *ADDRP to zero.
1058 The argument RAW_BUFFER must point to aligned memory. */
1061 deprecated_generic_get_saved_register (char *raw_buffer
, int *optimized
,
1063 struct frame_info
*frame
, int regnum
,
1064 enum lval_type
*lval
)
1066 if (!target_has_registers
)
1067 error ("No registers.");
1069 /* Normal systems don't optimize out things with register numbers. */
1070 if (optimized
!= NULL
)
1073 if (addrp
) /* default assumption: not found in memory */
1076 /* Note: since the current frame's registers could only have been
1077 saved by frames INTERIOR TO the current frame, we skip examining
1078 the current frame itself: otherwise, we would be getting the
1079 previous frame's registers which were saved by the current frame. */
1083 for (frame
= get_next_frame (frame
);
1084 frame_relative_level (frame
) >= 0;
1085 frame
= get_next_frame (frame
))
1087 if (get_frame_type (frame
) == DUMMY_FRAME
)
1089 if (lval
) /* found it in a CALL_DUMMY frame */
1092 /* FIXME: cagney/2002-06-26: This should be via the
1093 gdbarch_register_read() method so that it, on the
1094 fly, constructs either a raw or pseudo register
1095 from the raw register cache. */
1097 (deprecated_find_dummy_frame_regcache (get_frame_pc (frame
),
1098 get_frame_base (frame
)),
1099 regnum
, raw_buffer
);
1103 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
1104 if (deprecated_get_frame_saved_regs (frame
) != NULL
1105 && deprecated_get_frame_saved_regs (frame
)[regnum
] != 0)
1107 if (lval
) /* found it saved on the stack */
1108 *lval
= lval_memory
;
1109 if (regnum
== SP_REGNUM
)
1111 if (raw_buffer
) /* SP register treated specially */
1112 /* NOTE: cagney/2003-05-09: In-line store_address
1113 with it's body - store_unsigned_integer. */
1114 store_unsigned_integer (raw_buffer
,
1115 DEPRECATED_REGISTER_RAW_SIZE (regnum
),
1116 deprecated_get_frame_saved_regs (frame
)[regnum
]);
1120 if (addrp
) /* any other register */
1121 *addrp
= deprecated_get_frame_saved_regs (frame
)[regnum
];
1123 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], raw_buffer
,
1124 DEPRECATED_REGISTER_RAW_SIZE (regnum
));
1131 /* If we get thru the loop to this point, it means the register was
1132 not saved in any frame. Return the actual live-register value. */
1134 if (lval
) /* found it in a live register */
1135 *lval
= lval_register
;
1137 *addrp
= DEPRECATED_REGISTER_BYTE (regnum
);
1139 deprecated_read_register_gen (regnum
, raw_buffer
);
1142 /* Determine the frame's type based on its PC. */
1144 static enum frame_type
1145 frame_type_from_pc (CORE_ADDR pc
)
1147 /* FIXME: cagney/2002-11-24: Can't yet directly call
1148 pc_in_dummy_frame() as some architectures don't set
1149 PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the
1150 latter is implemented by simply calling pc_in_dummy_frame). */
1151 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1152 && DEPRECATED_PC_IN_CALL_DUMMY (pc
, 0, 0))
1157 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
1158 if (PC_IN_SIGTRAMP (pc
, name
))
1159 return SIGTRAMP_FRAME
;
1161 return NORMAL_FRAME
;
1165 /* Create an arbitrary (i.e. address specified by user) or innermost frame.
1166 Always returns a non-NULL value. */
1169 create_new_frame (CORE_ADDR addr
, CORE_ADDR pc
)
1171 struct frame_info
*fi
;
1175 fprintf_unfiltered (gdb_stdlog
,
1176 "{ create_new_frame (addr=0x%s, pc=0x%s) ",
1177 paddr_nz (addr
), paddr_nz (pc
));
1180 fi
= frame_obstack_zalloc (sizeof (struct frame_info
));
1182 fi
->next
= create_sentinel_frame (current_regcache
);
1184 /* Select/initialize both the unwind function and the frame's type
1186 fi
->unwind
= frame_unwind_find_by_frame (fi
->next
);
1187 if (fi
->unwind
->type
!= UNKNOWN_FRAME
)
1188 fi
->type
= fi
->unwind
->type
;
1190 fi
->type
= frame_type_from_pc (pc
);
1193 deprecated_update_frame_base_hack (fi
, addr
);
1194 deprecated_update_frame_pc_hack (fi
, pc
);
1196 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1197 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, fi
);
1201 fprintf_unfiltered (gdb_stdlog
, "-> ");
1202 fprint_frame (gdb_stdlog
, fi
);
1203 fprintf_unfiltered (gdb_stdlog
, " }\n");
1209 /* Return the frame that THIS_FRAME calls (NULL if THIS_FRAME is the
1210 innermost frame). Be careful to not fall off the bottom of the
1211 frame chain and onto the sentinel frame. */
1214 get_next_frame (struct frame_info
*this_frame
)
1216 if (this_frame
->level
> 0)
1217 return this_frame
->next
;
1223 deprecated_get_next_frame_hack (struct frame_info
*this_frame
)
1225 return this_frame
->next
;
1228 /* Flush the entire frame cache. */
1231 flush_cached_frames (void)
1233 /* Since we can't really be sure what the first object allocated was */
1234 obstack_free (&frame_cache_obstack
, 0);
1235 obstack_init (&frame_cache_obstack
);
1237 current_frame
= NULL
; /* Invalidate cache */
1238 select_frame (NULL
);
1239 annotate_frames_invalid ();
1241 fprintf_unfiltered (gdb_stdlog
, "{ flush_cached_frames () }\n");
1244 /* Flush the frame cache, and start a new one if necessary. */
1247 reinit_frame_cache (void)
1249 flush_cached_frames ();
1251 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
1252 if (PIDGET (inferior_ptid
) != 0)
1254 select_frame (get_current_frame ());
1258 /* Create the previous frame using the deprecated methods
1259 INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */
1261 static struct frame_info
*
1262 legacy_get_prev_frame (struct frame_info
*this_frame
)
1264 CORE_ADDR address
= 0;
1265 struct frame_info
*prev
;
1268 /* Don't frame_debug print legacy_get_prev_frame() here, just
1269 confuses the output. */
1271 /* Allocate the new frame.
1273 There is no reason to worry about memory leaks, should the
1274 remainder of the function fail. The allocated memory will be
1275 quickly reclaimed when the frame cache is flushed, and the `we've
1276 been here before' check, in get_prev_frame will stop repeated
1277 memory allocation calls. */
1278 prev
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
1279 prev
->level
= this_frame
->level
+ 1;
1281 /* Do not completly wire it in to the frame chain. Some (bad) code
1282 in INIT_FRAME_EXTRA_INFO tries to look along frame->prev to pull
1283 some fancy tricks (of course such code is, by definition,
1286 On the other hand, methods, such as get_frame_pc() and
1287 get_frame_base() rely on being able to walk along the frame
1288 chain. Make certain that at least they work by providing that
1289 link. Of course things manipulating prev can't go back. */
1290 prev
->next
= this_frame
;
1292 /* NOTE: cagney/2002-11-18: Should have been correctly setting the
1293 frame's type here, before anything else, and not last, at the
1294 bottom of this function. The various
1295 DEPRECATED_INIT_EXTRA_FRAME_INFO, DEPRECATED_INIT_FRAME_PC,
1296 DEPRECATED_INIT_FRAME_PC_FIRST and
1297 DEPRECATED_FRAME_INIT_SAVED_REGS methods are full of work-arounds
1298 that handle the frame not being correctly set from the start.
1299 Unfortunately those same work-arounds rely on the type defaulting
1300 to NORMAL_FRAME. Ulgh! The new frame code does not have this
1302 prev
->type
= UNKNOWN_FRAME
;
1304 /* A legacy frame's ID is always computed here. Mark it as valid. */
1305 prev
->this_id
.p
= 1;
1307 /* Handle sentinel frame unwind as a special case. */
1308 if (this_frame
->level
< 0)
1310 /* Try to unwind the PC. If that doesn't work, assume we've reached
1311 the oldest frame and simply return. Is there a better sentinal
1312 value? The unwound PC value is then used to initialize the new
1313 previous frame's type.
1315 Note that the pc-unwind is intentionally performed before the
1316 frame chain. This is ok since, for old targets, both
1317 frame_pc_unwind (nee, DEPRECATED_FRAME_SAVED_PC) and
1318 DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
1319 have already been initialized (using
1320 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1323 By unwinding the PC first, it becomes possible to, in the case of
1324 a dummy frame, avoid also unwinding the frame ID. This is
1325 because (well ignoring the PPC) a dummy frame can be located
1326 using THIS_FRAME's frame ID. */
1328 deprecated_update_frame_pc_hack (prev
, frame_pc_unwind (this_frame
));
1329 if (get_frame_pc (prev
) == 0)
1331 /* The allocated PREV_FRAME will be reclaimed when the frame
1332 obstack is next purged. */
1335 fprintf_unfiltered (gdb_stdlog
, "-> ");
1336 fprint_frame (gdb_stdlog
, NULL
);
1337 fprintf_unfiltered (gdb_stdlog
,
1338 " // unwound legacy PC zero }\n");
1343 /* Set the unwind functions based on that identified PC. Ditto
1344 for the "type" but strongly prefer the unwinder's frame type. */
1345 prev
->unwind
= frame_unwind_find_by_frame (prev
->next
);
1346 if (prev
->unwind
->type
== UNKNOWN_FRAME
)
1347 prev
->type
= frame_type_from_pc (get_frame_pc (prev
));
1349 prev
->type
= prev
->unwind
->type
;
1351 /* Find the prev's frame's ID. */
1352 if (prev
->type
== DUMMY_FRAME
1353 && gdbarch_unwind_dummy_id_p (current_gdbarch
))
1355 /* When unwinding a normal frame, the stack structure is
1356 determined by analyzing the frame's function's code (be
1357 it using brute force prologue analysis, or the dwarf2
1358 CFI). In the case of a dummy frame, that simply isn't
1359 possible. The The PC is either the program entry point,
1360 or some random address on the stack. Trying to use that
1361 PC to apply standard frame ID unwind techniques is just
1362 asking for trouble. */
1363 /* Use an architecture specific method to extract the prev's
1364 dummy ID from the next frame. Note that this method uses
1365 frame_register_unwind to obtain the register values
1366 needed to determine the dummy frame's ID. */
1367 prev
->this_id
.value
= gdbarch_unwind_dummy_id (current_gdbarch
,
1372 /* We're unwinding a sentinel frame, the PC of which is
1373 pointing at a stack dummy. Fake up the dummy frame's ID
1374 using the same sequence as is found a traditional
1375 unwinder. Once all architectures supply the
1376 unwind_dummy_id method, this code can go away. */
1377 prev
->this_id
.value
= frame_id_build (deprecated_read_fp (),
1381 /* Check that the unwound ID is valid. */
1382 if (!frame_id_p (prev
->this_id
.value
))
1386 fprintf_unfiltered (gdb_stdlog
, "-> ");
1387 fprint_frame (gdb_stdlog
, NULL
);
1388 fprintf_unfiltered (gdb_stdlog
,
1389 " // unwound legacy ID invalid }\n");
1394 /* Check that the new frame isn't inner to (younger, below,
1395 next) the old frame. If that happens the frame unwind is
1397 /* FIXME: cagney/2003-02-25: Ignore the sentinel frame since
1398 that doesn't have a valid frame ID. Should instead set the
1399 sentinel frame's frame ID to a `sentinel'. Leave it until
1400 after the switch to storing the frame ID, instead of the
1401 frame base, in the frame object. */
1404 this_frame
->prev
= prev
;
1406 /* FIXME: cagney/2002-01-19: This call will go away. Instead of
1407 initializing extra info, all frames will use the frame_cache
1408 (passed to the unwind functions) to store additional frame
1409 info. Unfortunately legacy targets can't use
1410 legacy_get_prev_frame() to unwind the sentinel frame and,
1411 consequently, are forced to take this code path and rely on
1412 the below call to DEPRECATED_INIT_EXTRA_FRAME_INFO to
1413 initialize the inner-most frame. */
1414 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1416 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, prev
);
1419 if (prev
->type
== NORMAL_FRAME
)
1420 prev
->this_id
.value
.code_addr
1421 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1425 fprintf_unfiltered (gdb_stdlog
, "-> ");
1426 fprint_frame (gdb_stdlog
, prev
);
1427 fprintf_unfiltered (gdb_stdlog
, " } // legacy innermost frame\n");
1432 /* This code only works on normal frames. A sentinel frame, where
1433 the level is -1, should never reach this code. */
1434 gdb_assert (this_frame
->level
>= 0);
1436 /* On some machines it is possible to call a function without
1437 setting up a stack frame for it. On these machines, we
1438 define this macro to take two args; a frameinfo pointer
1439 identifying a frame and a variable to set or clear if it is
1440 or isn't leafless. */
1442 /* Still don't want to worry about this except on the innermost
1443 frame. This macro will set FROMLEAF if THIS_FRAME is a frameless
1444 function invocation. */
1445 if (this_frame
->level
== 0)
1446 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
1447 the frame chain, not just the inner most frame! The generic,
1448 per-architecture, frame code should handle this and the below
1449 should simply be removed. */
1450 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (this_frame
);
1455 /* A frameless inner-most frame. The `FP' (which isn't an
1456 architecture frame-pointer register!) of the caller is the same
1458 /* FIXME: 2002-11-09: There isn't any reason to special case this
1459 edge condition. Instead the per-architecture code should hande
1461 /* FIXME: cagney/2003-06-16: This returns the inner most stack
1462 address for the previous frame, that, however, is wrong. It
1463 should be the inner most stack address for the previous to
1464 previous frame. This is because it is the previous to previous
1465 frame's innermost stack address that is constant through out
1466 the lifetime of the previous frame (trust me :-). */
1467 address
= get_frame_base (this_frame
);
1470 /* Two macros defined in tm.h specify the machine-dependent
1471 actions to be performed here.
1473 First, get the frame's chain-pointer.
1475 If that is zero, the frame is the outermost frame or a leaf
1476 called by the outermost frame. This means that if start
1477 calls main without a frame, we'll return 0 (which is fine
1480 Nope; there's a problem. This also returns when the current
1481 routine is a leaf of main. This is unacceptable. We move
1482 this to after the ffi test; I'd rather have backtraces from
1483 start go curfluy than have an abort called from main not show
1485 if (DEPRECATED_FRAME_CHAIN_P ())
1486 address
= DEPRECATED_FRAME_CHAIN (this_frame
);
1489 /* Someone is part way through coverting an old architecture
1490 to the new frame code. Implement FRAME_CHAIN the way the
1492 /* Find PREV frame's unwinder. */
1493 prev
->unwind
= frame_unwind_find_by_frame (this_frame
->next
);
1494 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
1495 type in the frame, the unwinder's type should be returned
1496 directly. Unfortunately, legacy code, called by
1497 legacy_get_prev_frame, explicitly set the frames type
1498 using the method deprecated_set_frame_type(). */
1499 prev
->type
= prev
->unwind
->type
;
1500 /* Find PREV frame's ID. */
1501 prev
->unwind
->this_id (this_frame
,
1502 &prev
->prologue_cache
,
1503 &prev
->this_id
.value
);
1504 prev
->this_id
.p
= 1;
1505 address
= prev
->this_id
.value
.stack_addr
;
1508 if (!legacy_frame_chain_valid (address
, this_frame
))
1512 fprintf_unfiltered (gdb_stdlog
, "-> ");
1513 fprint_frame (gdb_stdlog
, NULL
);
1514 fprintf_unfiltered (gdb_stdlog
,
1515 " // legacy frame chain invalid }\n");
1524 fprintf_unfiltered (gdb_stdlog
, "-> ");
1525 fprint_frame (gdb_stdlog
, NULL
);
1526 fprintf_unfiltered (gdb_stdlog
,
1527 " // legacy frame chain NULL }\n");
1532 /* Link in the already allocated prev frame. */
1533 this_frame
->prev
= prev
;
1534 deprecated_update_frame_base_hack (prev
, address
);
1536 /* This change should not be needed, FIXME! We should determine
1537 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1538 after DEPRECATED_INIT_EXTRA_FRAME_INFO and come up with a simple
1539 way to express what goes on here.
1541 DEPRECATED_INIT_EXTRA_FRAME_INFO is called from two places:
1542 create_new_frame (where the PC is already set up) and here (where
1543 it isn't). DEPRECATED_INIT_FRAME_PC is only called from here,
1544 always after DEPRECATED_INIT_EXTRA_FRAME_INFO.
1546 The catch is the MIPS, where DEPRECATED_INIT_EXTRA_FRAME_INFO
1547 requires the PC value (which hasn't been set yet). Some other
1548 machines appear to require DEPRECATED_INIT_EXTRA_FRAME_INFO
1549 before they can do DEPRECATED_INIT_FRAME_PC. Phoo.
1551 We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
1552 complication to an already overcomplicated part of GDB.
1553 gnu@cygnus.com, 15Sep92.
1555 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
1556 DEPRECATED_INIT_EXTRA_FRAME_INFO, one possible scheme:
1558 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1559 (deprecated_read_fp ()), read_pc ()). Machines with extra frame
1560 info would do that (or the local equivalent) and then set the
1563 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1564 create_new_frame would no longer init extra frame info;
1565 SETUP_ARBITRARY_FRAME would have to do that.
1567 INIT_PREV_FRAME(fromleaf, prev) Replace
1568 DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC.
1569 This should also return a flag saying whether to keep the new
1570 frame, or whether to discard it, because on some machines (e.g.
1571 mips) it is really awkward to have DEPRECATED_FRAME_CHAIN_VALID
1572 called BEFORE DEPRECATED_INIT_EXTRA_FRAME_INFO (there is no good
1573 way to get information deduced in DEPRECATED_FRAME_CHAIN_VALID
1574 into the extra fields of the new frame). std_frame_pc(fromleaf,
1577 This is the default setting for INIT_PREV_FRAME. It just does
1578 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1579 will call it from INIT_PREV_FRAME (either at the beginning, the
1580 end, or in the middle). Some machines won't use it.
1582 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1584 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1585 reason for things to be this complicated.
1587 The trick is to assume that there is always a frame. Instead of
1588 special casing the inner-most frame, create fake frame
1589 (containing the hardware registers) that is inner to the
1590 user-visible inner-most frame (...) and then unwind from that.
1591 That way architecture code can use use the standard
1592 frame_XX_unwind() functions and not differentiate between the
1593 inner most and any other case.
1595 Since there is always a frame to unwind from, there is always
1596 somewhere (THIS_FRAME) to store all the info needed to construct
1597 a new (previous) frame without having to first create it. This
1598 means that the convolution below - needing to carefully order a
1599 frame's initialization - isn't needed.
1601 The irony here though, is that DEPRECATED_FRAME_CHAIN(), at least
1602 for a more up-to-date architecture, always calls
1603 FRAME_SAVED_PC(), and FRAME_SAVED_PC() computes the PC but
1604 without first needing the frame! Instead of the convolution
1605 below, we could have simply called FRAME_SAVED_PC() and been done
1606 with it! Note that FRAME_SAVED_PC() is being superseed by
1607 frame_pc_unwind() and that function does have somewhere to cache
1610 if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
1611 deprecated_update_frame_pc_hack (prev
,
1612 DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf
,
1615 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1616 DEPRECATED_INIT_EXTRA_FRAME_INFO (fromleaf
, prev
);
1618 /* This entry is in the frame queue now, which is good since
1619 FRAME_SAVED_PC may use that queue to figure out its value (see
1620 tm-sparc.h). We want the pc saved in the inferior frame. */
1621 if (DEPRECATED_INIT_FRAME_PC_P ())
1622 deprecated_update_frame_pc_hack (prev
,
1623 DEPRECATED_INIT_FRAME_PC (fromleaf
,
1626 /* If ->frame and ->pc are unchanged, we are in the process of
1627 getting ourselves into an infinite backtrace. Some architectures
1628 check this in DEPRECATED_FRAME_CHAIN or thereabouts, but it seems
1629 like there is no reason this can't be an architecture-independent
1631 if (get_frame_base (prev
) == get_frame_base (this_frame
)
1632 && get_frame_pc (prev
) == get_frame_pc (this_frame
))
1634 this_frame
->prev
= NULL
;
1635 obstack_free (&frame_cache_obstack
, prev
);
1638 fprintf_unfiltered (gdb_stdlog
, "-> ");
1639 fprint_frame (gdb_stdlog
, NULL
);
1640 fprintf_unfiltered (gdb_stdlog
,
1641 " // legacy this.id == prev.id }\n");
1646 /* Initialize the code used to unwind the frame PREV based on the PC
1647 (and probably other architectural information). The PC lets you
1648 check things like the debug info at that point (dwarf2cfi?) and
1649 use that to decide how the frame should be unwound.
1651 If there isn't a FRAME_CHAIN, the code above will have already
1653 if (prev
->unwind
== NULL
)
1654 prev
->unwind
= frame_unwind_find_by_frame (prev
->next
);
1656 /* If the unwinder provides a frame type, use it. Otherwize
1657 continue on to that heuristic mess. */
1658 if (prev
->unwind
->type
!= UNKNOWN_FRAME
)
1660 prev
->type
= prev
->unwind
->type
;
1661 if (prev
->type
== NORMAL_FRAME
)
1662 /* FIXME: cagney/2003-06-16: would get_frame_pc() be better? */
1663 prev
->this_id
.value
.code_addr
1664 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1667 fprintf_unfiltered (gdb_stdlog
, "-> ");
1668 fprint_frame (gdb_stdlog
, prev
);
1669 fprintf_unfiltered (gdb_stdlog
, " } // legacy with unwound type\n");
1674 /* NOTE: cagney/2002-11-18: The code segments, found in
1675 create_new_frame and get_prev_frame(), that initializes the
1676 frames type is subtly different. The latter only updates ->type
1677 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1678 get_prev_frame() overriding the frame's type when the INIT code
1679 has previously set it. This is really somewhat bogus. The
1680 initialization, as seen in create_new_frame(), should occur
1681 before the INIT function has been called. */
1682 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1683 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
1684 ? DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (prev
), 0, 0)
1685 : pc_in_dummy_frame (get_frame_pc (prev
))))
1686 prev
->type
= DUMMY_FRAME
;
1689 /* FIXME: cagney/2002-11-10: This should be moved to before the
1690 INIT code above so that the INIT code knows what the frame's
1691 type is (in fact, for a [generic] dummy-frame, the type can
1692 be set and then the entire initialization can be skipped.
1693 Unforunatly, its the INIT code that sets the PC (Hmm, catch
1696 find_pc_partial_function (get_frame_pc (prev
), &name
, NULL
, NULL
);
1697 if (PC_IN_SIGTRAMP (get_frame_pc (prev
), name
))
1698 prev
->type
= SIGTRAMP_FRAME
;
1699 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1700 architectures are forcing the frame's type in INIT so we
1701 don't want to override it here. Remember, NORMAL_FRAME == 0,
1702 so it all works (just :-/). Once this initialization is
1703 moved to the start of this function, all this nastness will
1707 if (prev
->type
== NORMAL_FRAME
)
1708 prev
->this_id
.value
.code_addr
1709 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1713 fprintf_unfiltered (gdb_stdlog
, "-> ");
1714 fprint_frame (gdb_stdlog
, prev
);
1715 fprintf_unfiltered (gdb_stdlog
, " } // legacy with confused type\n");
1721 /* Return a structure containing various interesting information
1722 about the frame that called THIS_FRAME. Returns NULL
1723 if there is no such frame. */
1726 get_prev_frame (struct frame_info
*this_frame
)
1728 struct frame_info
*prev_frame
;
1732 fprintf_unfiltered (gdb_stdlog
, "{ get_prev_frame (this_frame=");
1733 if (this_frame
!= NULL
)
1734 fprintf_unfiltered (gdb_stdlog
, "%d", this_frame
->level
);
1736 fprintf_unfiltered (gdb_stdlog
, "<NULL>");
1737 fprintf_unfiltered (gdb_stdlog
, ") ");
1740 /* Return the inner-most frame, when the caller passes in NULL. */
1741 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
1742 caller should have previously obtained a valid frame using
1743 get_selected_frame() and then called this code - only possibility
1744 I can think of is code behaving badly.
1746 NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
1747 block_innermost_frame(). It does the sequence: frame = NULL;
1748 while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
1749 it couldn't be written better, I don't know.
1751 NOTE: cagney/2003-01-11: I suspect what is happening is
1752 block_innermost_frame() is, when the target has no state
1753 (registers, memory, ...), still calling this function. The
1754 assumption being that this function will return NULL indicating
1755 that a frame isn't possible, rather than checking that the target
1756 has state and then calling get_current_frame() and
1757 get_prev_frame(). This is a guess mind. */
1758 if (this_frame
== NULL
)
1760 /* NOTE: cagney/2002-11-09: There was a code segment here that
1761 would error out when CURRENT_FRAME was NULL. The comment
1762 that went with it made the claim ...
1764 ``This screws value_of_variable, which just wants a nice
1765 clean NULL return from block_innermost_frame if there are no
1766 frames. I don't think I've ever seen this message happen
1767 otherwise. And returning NULL here is a perfectly legitimate
1770 Per the above, this code shouldn't even be called with a NULL
1772 return current_frame
;
1775 /* There is always a frame. If this assertion fails, suspect that
1776 something should be calling get_selected_frame() or
1777 get_current_frame(). */
1778 gdb_assert (this_frame
!= NULL
);
1780 /* Make sure we pass an address within THIS_FRAME's code block to
1781 inside_main_func. Otherwise, we might stop unwinding at a
1782 function which has a call instruction as its last instruction if
1783 that function immediately precedes main(). */
1784 if (this_frame
->level
>= 0
1785 && !backtrace_past_main
1786 && inside_main_func (get_frame_address_in_block (this_frame
)))
1787 /* Don't unwind past main(), bug always unwind the sentinel frame.
1788 Note, this is done _before_ the frame has been marked as
1789 previously unwound. That way if the user later decides to
1790 allow unwinds past main(), that just happens. */
1793 fprintf_unfiltered (gdb_stdlog
, "-> NULL // inside main func }\n");
1797 if (this_frame
->level
> backtrace_limit
)
1799 error ("Backtrace limit of %d exceeded", backtrace_limit
);
1802 /* If we're already inside the entry function for the main objfile,
1803 then it isn't valid. Don't apply this test to a dummy frame -
1804 dummy frame PC's typically land in the entry func. Don't apply
1805 this test to the sentinel frame. Sentinel frames should always
1806 be allowed to unwind. */
1807 /* NOTE: cagney/2003-02-25: Don't enable until someone has found
1808 hard evidence that this is needed. */
1809 /* NOTE: cagney/2003-07-07: Fixed a bug in inside_main_func - wasn't
1810 checking for "main" in the minimal symbols. With that fixed
1811 asm-source tests now stop in "main" instead of halting the
1812 backtrace in wierd and wonderful ways somewhere inside the entry
1813 file. Suspect that deprecated_inside_entry_file and
1814 inside_entry_func tests were added to work around that (now
1816 /* NOTE: cagney/2003-07-15: danielj (if I'm reading it right)
1817 suggested having the inside_entry_func test use the
1818 inside_main_func msymbol trick (along with entry_point_address I
1819 guess) to determine the address range of the start function.
1820 That should provide a far better stopper than the current
1822 /* NOTE: cagney/2003-07-15: Need to add a "set backtrace
1823 beyond-entry-func" command so that this can be selectively
1827 && backtrace_beyond_entry_func
1829 && this_frame
->type
!= DUMMY_FRAME
&& this_frame
->level
>= 0
1830 && inside_entry_func (get_frame_pc (this_frame
)))
1834 fprintf_unfiltered (gdb_stdlog
, "-> ");
1835 fprint_frame (gdb_stdlog
, NULL
);
1836 fprintf_unfiltered (gdb_stdlog
, "// inside entry func }\n");
1841 /* Only try to do the unwind once. */
1842 if (this_frame
->prev_p
)
1846 fprintf_unfiltered (gdb_stdlog
, "-> ");
1847 fprint_frame (gdb_stdlog
, this_frame
->prev
);
1848 fprintf_unfiltered (gdb_stdlog
, " // cached \n");
1850 return this_frame
->prev
;
1852 this_frame
->prev_p
= 1;
1854 /* If we're inside the entry file, it isn't valid. Don't apply this
1855 test to a dummy frame - dummy frame PC's typically land in the
1856 entry file. Don't apply this test to the sentinel frame.
1857 Sentinel frames should always be allowed to unwind. */
1858 /* NOTE: drow/2002-12-25: should there be a way to disable this
1859 check? It assumes a single small entry file, and the way some
1860 debug readers (e.g. dbxread) figure out which object is the
1861 entry file is somewhat hokey. */
1862 /* NOTE: cagney/2003-01-10: If there is a way of disabling this test
1863 then it should probably be moved to before the ->prev_p test,
1865 /* NOTE: vinschen/2003-04-01: Disabled. It turns out that the call
1866 to deprecated_inside_entry_file destroys a meaningful backtrace
1867 under some conditions. E. g. the backtrace tests in the
1868 asm-source testcase are broken for some targets. In this test
1869 the functions are all implemented as part of one file and the
1870 testcase is not necessarily linked with a start file (depending
1871 on the target). What happens is, that the first frame is printed
1872 normaly and following frames are treated as being inside the
1873 enttry file then. This way, only the #0 frame is printed in the
1874 backtrace output. */
1876 && this_frame
->type
!= DUMMY_FRAME
&& this_frame
->level
>= 0
1877 && deprecated_inside_entry_file (get_frame_pc (this_frame
)))
1881 fprintf_unfiltered (gdb_stdlog
, "-> ");
1882 fprint_frame (gdb_stdlog
, NULL
);
1883 fprintf_unfiltered (gdb_stdlog
, " // inside entry file }\n");
1888 /* If any of the old frame initialization methods are around, use
1889 the legacy get_prev_frame method. */
1890 if (legacy_frame_p (current_gdbarch
))
1892 prev_frame
= legacy_get_prev_frame (this_frame
);
1896 /* Check that this frame's ID was valid. If it wasn't, don't try to
1897 unwind to the prev frame. Be careful to not apply this test to
1898 the sentinel frame. */
1899 if (this_frame
->level
>= 0 && !frame_id_p (get_frame_id (this_frame
)))
1903 fprintf_unfiltered (gdb_stdlog
, "-> ");
1904 fprint_frame (gdb_stdlog
, NULL
);
1905 fprintf_unfiltered (gdb_stdlog
, " // this ID is NULL }\n");
1910 /* Check that this frame's ID isn't inner to (younger, below, next)
1911 the next frame. This happens when a frame unwind goes backwards.
1912 Since the sentinel frame doesn't really exist, don't compare the
1913 inner-most against that sentinel. */
1914 if (this_frame
->level
> 0
1915 && frame_id_inner (get_frame_id (this_frame
),
1916 get_frame_id (this_frame
->next
)))
1917 error ("Previous frame inner to this frame (corrupt stack?)");
1919 /* Check that this and the next frame are not identical. If they
1920 are, there is most likely a stack cycle. As with the inner-than
1921 test above, avoid comparing the inner-most and sentinel frames. */
1922 if (this_frame
->level
> 0
1923 && frame_id_eq (get_frame_id (this_frame
),
1924 get_frame_id (this_frame
->next
)))
1925 error ("Previous frame identical to this frame (corrupt stack?)");
1927 /* Allocate the new frame but do not wire it in to the frame chain.
1928 Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
1929 frame->next to pull some fancy tricks (of course such code is, by
1930 definition, recursive). Try to prevent it.
1932 There is no reason to worry about memory leaks, should the
1933 remainder of the function fail. The allocated memory will be
1934 quickly reclaimed when the frame cache is flushed, and the `we've
1935 been here before' check above will stop repeated memory
1936 allocation calls. */
1937 prev_frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
1938 prev_frame
->level
= this_frame
->level
+ 1;
1940 /* Try to unwind the PC. If that doesn't work, assume we've reached
1941 the oldest frame and simply return. Is there a better sentinal
1942 value? The unwound PC value is then used to initialize the new
1943 previous frame's type.
1945 Note that the pc-unwind is intentionally performed before the
1946 frame chain. This is ok since, for old targets, both
1947 frame_pc_unwind (nee, FRAME_SAVED_PC) and
1948 DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
1949 have already been initialized (using
1950 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1953 By unwinding the PC first, it becomes possible to, in the case of
1954 a dummy frame, avoid also unwinding the frame ID. This is
1955 because (well ignoring the PPC) a dummy frame can be located
1956 using THIS_FRAME's frame ID. */
1958 if (frame_pc_unwind (this_frame
) == 0)
1960 /* The allocated PREV_FRAME will be reclaimed when the frame
1961 obstack is next purged. */
1964 fprintf_unfiltered (gdb_stdlog
, "-> ");
1965 fprint_frame (gdb_stdlog
, NULL
);
1966 fprintf_unfiltered (gdb_stdlog
, " // unwound PC zero }\n");
1971 /* Don't yet compute ->unwind (and hence ->type). It is computed
1972 on-demand in get_frame_type, frame_register_unwind, and
1975 /* Don't yet compute the frame's ID. It is computed on-demand by
1978 /* The unwound frame ID is validate at the start of this function,
1979 as part of the logic to decide if that frame should be further
1980 unwound, and not here while the prev frame is being created.
1981 Doing this makes it possible for the user to examine a frame that
1982 has an invalid frame ID.
1984 Some very old VAX code noted: [...] For the sake of argument,
1985 suppose that the stack is somewhat trashed (which is one reason
1986 that "info frame" exists). So, return 0 (indicating we don't
1987 know the address of the arglist) if we don't know what frame this
1991 this_frame
->prev
= prev_frame
;
1992 prev_frame
->next
= this_frame
;
1996 fprintf_unfiltered (gdb_stdlog
, "-> ");
1997 fprint_frame (gdb_stdlog
, prev_frame
);
1998 fprintf_unfiltered (gdb_stdlog
, " }\n");
2005 get_frame_pc (struct frame_info
*frame
)
2007 gdb_assert (frame
->next
!= NULL
);
2008 return frame_pc_unwind (frame
->next
);
2011 /* Return an address of that falls within the frame's code block. */
2014 frame_unwind_address_in_block (struct frame_info
*next_frame
)
2016 /* A draft address. */
2017 CORE_ADDR pc
= frame_pc_unwind (next_frame
);
2019 /* If THIS frame is not inner most (i.e., NEXT isn't the sentinel),
2020 and NEXT is `normal' (i.e., not a sigtramp, dummy, ....) THIS
2021 frame's PC ends up pointing at the instruction fallowing the
2022 "call". Adjust that PC value so that it falls on the call
2023 instruction (which, hopefully, falls within THIS frame's code
2024 block. So far it's proved to be a very good approximation. See
2025 get_frame_type for why ->type can't be used. */
2026 if (next_frame
->level
>= 0
2027 && get_frame_type (next_frame
) == NORMAL_FRAME
)
2033 get_frame_address_in_block (struct frame_info
*this_frame
)
2035 return frame_unwind_address_in_block (this_frame
->next
);
2039 pc_notcurrent (struct frame_info
*frame
)
2041 /* If FRAME is not the innermost frame, that normally means that
2042 FRAME->pc points at the return instruction (which is *after* the
2043 call instruction), and we want to get the line containing the
2044 call (because the call is where the user thinks the program is).
2045 However, if the next frame is either a SIGTRAMP_FRAME or a
2046 DUMMY_FRAME, then the next frame will contain a saved interrupt
2047 PC and such a PC indicates the current (rather than next)
2048 instruction/line, consequently, for such cases, want to get the
2049 line containing fi->pc. */
2050 struct frame_info
*next
= get_next_frame (frame
);
2051 int notcurrent
= (next
!= NULL
&& get_frame_type (next
) == NORMAL_FRAME
);
2056 find_frame_sal (struct frame_info
*frame
, struct symtab_and_line
*sal
)
2058 (*sal
) = find_pc_line (get_frame_pc (frame
), pc_notcurrent (frame
));
2061 /* Per "frame.h", return the ``address'' of the frame. Code should
2062 really be using get_frame_id(). */
2064 get_frame_base (struct frame_info
*fi
)
2066 return get_frame_id (fi
).stack_addr
;
2069 /* High-level offsets into the frame. Used by the debug info. */
2072 get_frame_base_address (struct frame_info
*fi
)
2074 if (get_frame_type (fi
) != NORMAL_FRAME
)
2076 if (fi
->base
== NULL
)
2077 fi
->base
= frame_base_find_by_frame (fi
->next
);
2078 /* Sneaky: If the low-level unwind and high-level base code share a
2079 common unwinder, let them share the prologue cache. */
2080 if (fi
->base
->unwind
== fi
->unwind
)
2081 return fi
->base
->this_base (fi
->next
, &fi
->prologue_cache
);
2082 return fi
->base
->this_base (fi
->next
, &fi
->base_cache
);
2086 get_frame_locals_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_locals (fi
->next
, cache
);
2104 get_frame_args_address (struct frame_info
*fi
)
2107 if (get_frame_type (fi
) != NORMAL_FRAME
)
2109 /* If there isn't a frame address method, find it. */
2110 if (fi
->base
== NULL
)
2111 fi
->base
= frame_base_find_by_frame (fi
->next
);
2112 /* Sneaky: If the low-level unwind and high-level base code share a
2113 common unwinder, let them share the prologue cache. */
2114 if (fi
->base
->unwind
== fi
->unwind
)
2115 cache
= &fi
->prologue_cache
;
2117 cache
= &fi
->base_cache
;
2118 return fi
->base
->this_args (fi
->next
, cache
);
2121 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
2122 or -1 for a NULL frame. */
2125 frame_relative_level (struct frame_info
*fi
)
2134 get_frame_type (struct frame_info
*frame
)
2136 /* Some targets still don't use [generic] dummy frames. Catch them
2138 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
2139 && deprecated_frame_in_dummy (frame
))
2142 /* Some legacy code, e.g, mips_init_extra_frame_info() wants
2143 to determine the frame's type prior to it being completely
2144 initialized. Don't attempt to lazily initialize ->unwind for
2145 legacy code. It will be initialized in legacy_get_prev_frame(). */
2146 if (frame
->unwind
== NULL
&& !legacy_frame_p (current_gdbarch
))
2148 /* Initialize the frame's unwinder because it is that which
2149 provides the frame's type. */
2150 frame
->unwind
= frame_unwind_find_by_frame (frame
->next
);
2151 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
2152 type in the frame, the unwinder's type should be returned
2153 directly. Unfortunately, legacy code, called by
2154 legacy_get_prev_frame, explicitly set the frames type using
2155 the method deprecated_set_frame_type(). */
2156 gdb_assert (frame
->unwind
->type
!= UNKNOWN_FRAME
);
2157 frame
->type
= frame
->unwind
->type
;
2159 if (frame
->type
== UNKNOWN_FRAME
)
2160 return NORMAL_FRAME
;
2166 deprecated_set_frame_type (struct frame_info
*frame
, enum frame_type type
)
2168 /* Arrrg! See comment in "frame.h". */
2172 struct frame_extra_info
*
2173 get_frame_extra_info (struct frame_info
*fi
)
2175 return fi
->extra_info
;
2178 struct frame_extra_info
*
2179 frame_extra_info_zalloc (struct frame_info
*fi
, long size
)
2181 fi
->extra_info
= frame_obstack_zalloc (size
);
2182 return fi
->extra_info
;
2186 deprecated_update_frame_pc_hack (struct frame_info
*frame
, CORE_ADDR pc
)
2189 fprintf_unfiltered (gdb_stdlog
,
2190 "{ deprecated_update_frame_pc_hack (frame=%d,pc=0x%s) }\n",
2191 frame
->level
, paddr_nz (pc
));
2192 /* NOTE: cagney/2003-03-11: Some architectures (e.g., Arm) are
2193 maintaining a locally allocated frame object. Since such frame's
2194 are not in the frame chain, it isn't possible to assume that the
2195 frame has a next. Sigh. */
2196 if (frame
->next
!= NULL
)
2198 /* While we're at it, update this frame's cached PC value, found
2199 in the next frame. Oh for the day when "struct frame_info"
2200 is opaque and this hack on hack can just go away. */
2201 frame
->next
->prev_pc
.value
= pc
;
2202 frame
->next
->prev_pc
.p
= 1;
2207 deprecated_update_frame_base_hack (struct frame_info
*frame
, CORE_ADDR base
)
2210 fprintf_unfiltered (gdb_stdlog
,
2211 "{ deprecated_update_frame_base_hack (frame=%d,base=0x%s) }\n",
2212 frame
->level
, paddr_nz (base
));
2213 /* See comment in "frame.h". */
2214 frame
->this_id
.value
.stack_addr
= base
;
2218 deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs
,
2219 long sizeof_extra_info
)
2221 struct frame_info
*frame
= XMALLOC (struct frame_info
);
2222 memset (frame
, 0, sizeof (*frame
));
2223 frame
->this_id
.p
= 1;
2224 make_cleanup (xfree
, frame
);
2225 if (sizeof_saved_regs
> 0)
2227 frame
->saved_regs
= xcalloc (1, sizeof_saved_regs
);
2228 make_cleanup (xfree
, frame
->saved_regs
);
2230 if (sizeof_extra_info
> 0)
2232 frame
->extra_info
= xcalloc (1, sizeof_extra_info
);
2233 make_cleanup (xfree
, frame
->extra_info
);
2238 /* Memory access methods. */
2241 get_frame_memory (struct frame_info
*this_frame
, CORE_ADDR addr
, void *buf
,
2244 read_memory (addr
, buf
, len
);
2248 get_frame_memory_signed (struct frame_info
*this_frame
, CORE_ADDR addr
,
2251 return read_memory_integer (addr
, len
);
2255 get_frame_memory_unsigned (struct frame_info
*this_frame
, CORE_ADDR addr
,
2258 return read_memory_unsigned_integer (addr
, len
);
2261 /* Architecture method. */
2264 get_frame_arch (struct frame_info
*this_frame
)
2266 return current_gdbarch
;
2269 /* Stack pointer methods. */
2272 get_frame_sp (struct frame_info
*this_frame
)
2274 return frame_sp_unwind (this_frame
->next
);
2278 frame_sp_unwind (struct frame_info
*next_frame
)
2280 /* Normality, an architecture that provides a way of obtaining any
2281 frame inner-most address. */
2282 if (gdbarch_unwind_sp_p (current_gdbarch
))
2283 return gdbarch_unwind_sp (current_gdbarch
, next_frame
);
2284 /* Things are looking grim. If it's the inner-most frame and there
2285 is a TARGET_READ_SP then that can be used. */
2286 if (next_frame
->level
< 0 && TARGET_READ_SP_P ())
2287 return TARGET_READ_SP ();
2288 /* Now things are really are grim. Hope that the value returned by
2289 the SP_REGNUM register is meaningful. */
2293 frame_unwind_unsigned_register (next_frame
, SP_REGNUM
, &sp
);
2296 internal_error (__FILE__
, __LINE__
, "Missing unwind SP method");
2301 legacy_frame_p (struct gdbarch
*current_gdbarch
)
2303 return (DEPRECATED_INIT_FRAME_PC_P ()
2304 || DEPRECATED_INIT_FRAME_PC_FIRST_P ()
2305 || DEPRECATED_INIT_EXTRA_FRAME_INFO_P ()
2306 || DEPRECATED_FRAME_CHAIN_P ()
2307 || !gdbarch_unwind_dummy_id_p (current_gdbarch
));
2310 extern initialize_file_ftype _initialize_frame
; /* -Wmissing-prototypes */
2312 static struct cmd_list_element
*set_backtrace_cmdlist
;
2313 static struct cmd_list_element
*show_backtrace_cmdlist
;
2316 set_backtrace_cmd (char *args
, int from_tty
)
2318 help_list (set_backtrace_cmdlist
, "set backtrace ", -1, gdb_stdout
);
2322 show_backtrace_cmd (char *args
, int from_tty
)
2324 cmd_show_list (show_backtrace_cmdlist
, from_tty
, "");
2328 _initialize_frame (void)
2330 obstack_init (&frame_cache_obstack
);
2332 add_prefix_cmd ("backtrace", class_maintenance
, set_backtrace_cmd
, "\
2333 Set backtrace specific variables.\n\
2334 Configure backtrace variables such as the backtrace limit",
2335 &set_backtrace_cmdlist
, "set backtrace ",
2336 0/*allow-unknown*/, &setlist
);
2337 add_prefix_cmd ("backtrace", class_maintenance
, show_backtrace_cmd
, "\
2338 Show backtrace specific variables\n\
2339 Show backtrace variables such as the backtrace limit",
2340 &show_backtrace_cmdlist
, "show backtrace ",
2341 0/*allow-unknown*/, &showlist
);
2343 add_setshow_boolean_cmd ("past-main", class_obscure
,
2344 &backtrace_past_main
, "\
2345 Set whether backtraces should continue past \"main\".\n\
2346 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2347 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2348 of the stack trace.", "\
2349 Show whether backtraces should continue past \"main\".\n\
2350 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2351 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2352 of the stack trace.",
2353 NULL
, NULL
, &set_backtrace_cmdlist
,
2354 &show_backtrace_cmdlist
);
2356 add_setshow_uinteger_cmd ("limit", class_obscure
,
2357 &backtrace_limit
, "\
2358 Set an upper bound on the number of backtrace levels.\n\
2359 No more than the specified number of frames can be displayed or examined.\n\
2360 Zero is unlimited.", "\
2361 Show the upper bound on the number of backtrace levels.",
2362 NULL
, NULL
, &set_backtrace_cmdlist
,
2363 &show_backtrace_cmdlist
);
2365 /* Debug this files internals. */
2366 add_show_from_set (add_set_cmd ("frame", class_maintenance
, var_zinteger
,
2367 &frame_debug
, "Set frame debugging.\n\
2368 When non-zero, frame specific internal debugging is enabled.", &setdebuglist
),