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. Unfortunatly, 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 /* If dwarf2 unwind frame informations is used, this structure holds
90 all related unwind data. */
91 struct context
*context
;
93 /* The frame's low-level unwinder and corresponding cache. The
94 low-level unwinder is responsible for unwinding register values
95 for the previous frame. The low-level unwind methods are
96 selected based on the presence, or otherwize, of register unwind
97 information such as CFI. */
99 const struct frame_unwind
*unwind
;
101 /* Cached copy of the previous frame's resume address. */
107 /* Cached copy of the previous frame's function address. */
114 /* This frame's ID. */
118 struct frame_id value
;
121 /* The frame's high-level base methods, and corresponding cache.
122 The high level base methods are selected based on the frame's
124 const struct frame_base
*base
;
127 /* Pointers to the next (down, inner, younger) and previous (up,
128 outer, older) frame_info's in the frame cache. */
129 struct frame_info
*next
; /* down, inner, younger */
131 struct frame_info
*prev
; /* up, outer, older */
134 /* Flag to control debugging. */
136 static int frame_debug
;
138 /* Flag to indicate whether backtraces should stop at main et.al. */
140 static int backtrace_past_main
;
141 static unsigned int backtrace_limit
= UINT_MAX
;
145 fprint_frame_id (struct ui_file
*file
, struct frame_id id
)
147 fprintf_unfiltered (file
, "{stack=0x%s,code=0x%s}",
148 paddr_nz (id
.stack_addr
),
149 paddr_nz (id
.code_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 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
236 type in the frame, the unwinder's type should be returned
237 directly. Unfortunatly, legacy code, called by
238 legacy_get_prev_frame, explicitly set the frames type
239 using the method deprecated_set_frame_type(). */
240 gdb_assert (fi
->unwind
->type
!= UNKNOWN_FRAME
);
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
;
256 const struct frame_id null_frame_id
; /* All zeros. */
259 frame_id_build (CORE_ADDR stack_addr
, CORE_ADDR code_addr
)
262 id
.stack_addr
= stack_addr
;
263 id
.code_addr
= code_addr
;
268 frame_id_p (struct frame_id l
)
271 /* The .code can be NULL but the .stack cannot. */
272 p
= (l
.stack_addr
!= 0);
275 fprintf_unfiltered (gdb_stdlog
, "{ frame_id_p (l=");
276 fprint_frame_id (gdb_stdlog
, l
);
277 fprintf_unfiltered (gdb_stdlog
, ") -> %d }\n", p
);
283 frame_id_eq (struct frame_id l
, struct frame_id r
)
286 if (l
.stack_addr
== 0 || r
.stack_addr
== 0)
287 /* Like a NaN, if either ID is invalid, the result is false. */
289 else if (l
.stack_addr
!= r
.stack_addr
)
290 /* If .stack addresses are different, the frames are different. */
292 else if (l
.code_addr
== 0 || r
.code_addr
== 0)
293 /* A zero code addr is a wild card, always succeed. */
295 else if (l
.code_addr
== r
.code_addr
)
296 /* The .stack and .code are identical, the ID's are identical. */
303 fprintf_unfiltered (gdb_stdlog
, "{ frame_id_eq (l=");
304 fprint_frame_id (gdb_stdlog
, l
);
305 fprintf_unfiltered (gdb_stdlog
, ",r=");
306 fprint_frame_id (gdb_stdlog
, r
);
307 fprintf_unfiltered (gdb_stdlog
, ") -> %d }\n", eq
);
313 frame_id_inner (struct frame_id l
, struct frame_id r
)
316 if (l
.stack_addr
== 0 || r
.stack_addr
== 0)
317 /* Like NaN, any operation involving an invalid ID always fails. */
320 /* Only return non-zero when strictly inner than. Note that, per
321 comment in "frame.h", there is some fuzz here. Frameless
322 functions are not strictly inner than (same .stack but
324 inner
= INNER_THAN (l
.stack_addr
, r
.stack_addr
);
327 fprintf_unfiltered (gdb_stdlog
, "{ frame_id_inner (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", inner
);
337 frame_find_by_id (struct frame_id id
)
339 struct frame_info
*frame
;
341 /* ZERO denotes the null frame, let the caller decide what to do
342 about it. Should it instead return get_current_frame()? */
343 if (!frame_id_p (id
))
346 for (frame
= get_current_frame ();
348 frame
= get_prev_frame (frame
))
350 struct frame_id
this = get_frame_id (frame
);
351 if (frame_id_eq (id
, this))
352 /* An exact match. */
354 if (frame_id_inner (id
, this))
357 /* Either, we're not yet gone far enough out along the frame
358 chain (inner(this,id), or we're comparing frameless functions
359 (same .base, different .func, no test available). Struggle
360 on until we've definitly gone to far. */
366 frame_pc_unwind (struct frame_info
*this_frame
)
368 if (!this_frame
->prev_pc
.p
)
371 if (gdbarch_unwind_pc_p (current_gdbarch
))
373 /* The right way. The `pure' way. The one true way. This
374 method depends solely on the register-unwind code to
375 determine the value of registers in THIS frame, and hence
376 the value of this frame's PC (resume address). A typical
377 implementation is no more than:
379 frame_unwind_register (this_frame, ISA_PC_REGNUM, buf);
380 return extract_unsigned_integer (buf, size of ISA_PC_REGNUM);
382 Note: this method is very heavily dependent on a correct
383 register-unwind implementation, it pays to fix that
384 method first; this method is frame type agnostic, since
385 it only deals with register values, it works with any
386 frame. This is all in stark contrast to the old
387 FRAME_SAVED_PC which would try to directly handle all the
388 different ways that a PC could be unwound. */
389 pc
= gdbarch_unwind_pc (current_gdbarch
, this_frame
);
391 else if (this_frame
->level
< 0)
393 /* FIXME: cagney/2003-03-06: Old code and and a sentinel
394 frame. Do like was always done. Fetch the PC's value
395 direct from the global registers array (via read_pc).
396 This assumes that this frame belongs to the current
397 global register cache. The assumption is dangerous. */
400 else if (DEPRECATED_FRAME_SAVED_PC_P ())
402 /* FIXME: cagney/2003-03-06: Old code, but not a sentinel
403 frame. Do like was always done. Note that this method,
404 unlike unwind_pc(), tries to handle all the different
405 frame cases directly. It fails. */
406 pc
= DEPRECATED_FRAME_SAVED_PC (this_frame
);
409 internal_error (__FILE__
, __LINE__
, "No gdbarch_unwind_pc method");
410 this_frame
->prev_pc
.value
= pc
;
411 this_frame
->prev_pc
.p
= 1;
413 fprintf_unfiltered (gdb_stdlog
,
414 "{ frame_pc_unwind (this_frame=%d) -> 0x%s }\n",
416 paddr_nz (this_frame
->prev_pc
.value
));
418 return this_frame
->prev_pc
.value
;
422 frame_func_unwind (struct frame_info
*fi
)
424 if (!fi
->prev_func
.p
)
426 /* Make certain that this, and not the adjacent, function is
428 CORE_ADDR addr_in_block
= frame_unwind_address_in_block (fi
);
430 fi
->prev_func
.addr
= get_pc_function_start (addr_in_block
);
432 fprintf_unfiltered (gdb_stdlog
,
433 "{ frame_func_unwind (fi=%d) -> 0x%s }\n",
434 fi
->level
, paddr_nz (fi
->prev_func
.addr
));
436 return fi
->prev_func
.addr
;
440 get_frame_func (struct frame_info
*fi
)
442 return frame_func_unwind (fi
->next
);
446 do_frame_unwind_register (void *src
, int regnum
, void *buf
)
448 frame_unwind_register (src
, regnum
, buf
);
453 frame_pop (struct frame_info
*this_frame
)
455 struct regcache
*scratch_regcache
;
456 struct cleanup
*cleanups
;
458 if (DEPRECATED_POP_FRAME_P ())
460 /* A legacy architecture that has implemented a custom pop
461 function. All new architectures should instead be using the
462 generic code below. */
463 DEPRECATED_POP_FRAME
;
467 /* Make a copy of all the register values unwound from this
468 frame. Save them in a scratch buffer so that there isn't a
469 race betweening trying to extract the old values from the
470 current_regcache while, at the same time writing new values
471 into that same cache. */
472 struct regcache
*scratch
= regcache_xmalloc (current_gdbarch
);
473 struct cleanup
*cleanups
= make_cleanup_regcache_xfree (scratch
);
474 regcache_save (scratch
, do_frame_unwind_register
, this_frame
);
475 /* FIXME: cagney/2003-03-16: It should be possible to tell the
476 target's register cache that it is about to be hit with a
477 burst register transfer and that the sequence of register
478 writes should be batched. The pair target_prepare_to_store()
479 and target_store_registers() kind of suggest this
480 functionality. Unfortunatly, they don't implement it. Their
481 lack of a formal definition can lead to targets writing back
482 bogus values (arguably a bug in the target code mind). */
483 /* Now copy those saved registers into the current regcache.
484 Here, regcache_cpy() calls regcache_restore(). */
485 regcache_cpy (current_regcache
, scratch
);
486 do_cleanups (cleanups
);
488 /* We've made right mess of GDB's local state, just discard
490 flush_cached_frames ();
494 frame_register_unwind (struct frame_info
*frame
, int regnum
,
495 int *optimizedp
, enum lval_type
*lvalp
,
496 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
498 struct frame_unwind_cache
*cache
;
502 fprintf_unfiltered (gdb_stdlog
,
503 "{ frame_register_unwind (frame=%d,regnum=\"%s\",...) ",
504 frame
->level
, frame_map_regnum_to_name (frame
, regnum
));
507 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
508 that the value proper does not need to be fetched. */
509 gdb_assert (optimizedp
!= NULL
);
510 gdb_assert (lvalp
!= NULL
);
511 gdb_assert (addrp
!= NULL
);
512 gdb_assert (realnump
!= NULL
);
513 /* gdb_assert (bufferp != NULL); */
515 /* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame
516 is broken. There is always a frame. If there, for some reason,
517 isn't, there is some pretty busted code as it should have
518 detected the problem before calling here. */
519 gdb_assert (frame
!= NULL
);
521 /* Find the unwinder. */
522 if (frame
->unwind
== NULL
)
524 frame
->unwind
= frame_unwind_find_by_frame (frame
->next
);
525 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
526 type in the frame, the unwinder's type should be returned
527 directly. Unfortunatly, legacy code, called by
528 legacy_get_prev_frame, explicitly set the frames type using
529 the method deprecated_set_frame_type(). */
530 gdb_assert (frame
->unwind
->type
!= UNKNOWN_FRAME
);
531 frame
->type
= frame
->unwind
->type
;
534 /* Ask this frame to unwind its register. See comment in
535 "frame-unwind.h" for why NEXT frame and this unwind cace are
537 frame
->unwind
->prev_register (frame
->next
, &frame
->prologue_cache
, regnum
,
538 optimizedp
, lvalp
, addrp
, realnump
, bufferp
);
542 fprintf_unfiltered (gdb_stdlog
, "->");
543 fprintf_unfiltered (gdb_stdlog
, " *optimizedp=%d", (*optimizedp
));
544 fprintf_unfiltered (gdb_stdlog
, " *lvalp=%d", (int) (*lvalp
));
545 fprintf_unfiltered (gdb_stdlog
, " *addrp=0x%s", paddr_nz ((*addrp
)));
546 fprintf_unfiltered (gdb_stdlog
, " *bufferp=");
548 fprintf_unfiltered (gdb_stdlog
, "<NULL>");
552 const unsigned char *buf
= bufferp
;
553 fprintf_unfiltered (gdb_stdlog
, "[");
554 for (i
= 0; i
< register_size (current_gdbarch
, regnum
); i
++)
555 fprintf_unfiltered (gdb_stdlog
, "%02x", buf
[i
]);
556 fprintf_unfiltered (gdb_stdlog
, "]");
558 fprintf_unfiltered (gdb_stdlog
, " }\n");
563 frame_register (struct frame_info
*frame
, int regnum
,
564 int *optimizedp
, enum lval_type
*lvalp
,
565 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
567 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
568 that the value proper does not need to be fetched. */
569 gdb_assert (optimizedp
!= NULL
);
570 gdb_assert (lvalp
!= NULL
);
571 gdb_assert (addrp
!= NULL
);
572 gdb_assert (realnump
!= NULL
);
573 /* gdb_assert (bufferp != NULL); */
575 /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
576 of the register in the register cache. It should instead return
577 the REGNUM corresponding to that register. Translate the . */
578 if (DEPRECATED_GET_SAVED_REGISTER_P ())
580 DEPRECATED_GET_SAVED_REGISTER (bufferp
, optimizedp
, addrp
, frame
,
582 /* Compute the REALNUM if the caller wants it. */
583 if (*lvalp
== lval_register
)
586 for (regnum
= 0; regnum
< NUM_REGS
+ NUM_PSEUDO_REGS
; regnum
++)
588 if (*addrp
== register_offset_hack (current_gdbarch
, regnum
))
594 internal_error (__FILE__
, __LINE__
,
595 "Failed to compute the register number corresponding"
596 " to 0x%s", paddr_d (*addrp
));
602 /* Obtain the register value by unwinding the register from the next
603 (more inner frame). */
604 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
605 frame_register_unwind (frame
->next
, regnum
, optimizedp
, lvalp
, addrp
,
610 frame_unwind_register (struct frame_info
*frame
, int regnum
, void *buf
)
616 frame_register_unwind (frame
, regnum
, &optimized
, &lval
, &addr
,
621 get_frame_register (struct frame_info
*frame
,
622 int regnum
, void *buf
)
624 frame_unwind_register (frame
->next
, regnum
, buf
);
628 frame_unwind_register_signed (struct frame_info
*frame
, int regnum
)
630 char buf
[MAX_REGISTER_SIZE
];
631 frame_unwind_register (frame
, regnum
, buf
);
632 return extract_signed_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
636 get_frame_register_signed (struct frame_info
*frame
, int regnum
)
638 return frame_unwind_register_signed (frame
->next
, regnum
);
642 frame_unwind_register_unsigned (struct frame_info
*frame
, int regnum
)
644 char buf
[MAX_REGISTER_SIZE
];
645 frame_unwind_register (frame
, regnum
, buf
);
646 return extract_unsigned_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
650 get_frame_register_unsigned (struct frame_info
*frame
, int regnum
)
652 return frame_unwind_register_unsigned (frame
->next
, regnum
);
656 frame_unwind_signed_register (struct frame_info
*frame
, int regnum
,
659 char buf
[MAX_REGISTER_SIZE
];
660 frame_unwind_register (frame
, regnum
, buf
);
661 (*val
) = extract_signed_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
665 frame_unwind_unsigned_register (struct frame_info
*frame
, int regnum
,
668 char buf
[MAX_REGISTER_SIZE
];
669 frame_unwind_register (frame
, regnum
, buf
);
670 (*val
) = extract_unsigned_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
674 frame_read_register (struct frame_info
*frame
, int regnum
, void *buf
)
676 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
677 frame_unwind_register (frame
->next
, regnum
, buf
);
681 frame_read_unsigned_register (struct frame_info
*frame
, int regnum
,
684 /* NOTE: cagney/2002-10-31: There is a bit of dogma here - there is
685 always a frame. Both this, and the equivalent
686 frame_read_signed_register() function, can only be called with a
687 valid frame. If, for some reason, this function is called
688 without a frame then the problem isn't here, but rather in the
689 caller. It should of first created a frame and then passed that
691 /* NOTE: cagney/2002-10-31: As a side bar, keep in mind that the
692 ``current_frame'' should not be treated as a special case. While
693 ``get_next_frame (current_frame) == NULL'' currently holds, it
694 should, as far as possible, not be relied upon. In the future,
695 ``get_next_frame (current_frame)'' may instead simply return a
696 normal frame object that simply always gets register values from
697 the register cache. Consequently, frame code should try to avoid
698 tests like ``if get_next_frame() == NULL'' and instead just rely
699 on recursive frame calls (like the below code) when manipulating
701 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
702 frame_unwind_unsigned_register (frame
->next
, regnum
, val
);
706 frame_read_signed_register (struct frame_info
*frame
, int regnum
,
709 /* See note above in frame_read_unsigned_register(). */
710 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
711 frame_unwind_signed_register (frame
->next
, regnum
, val
);
715 put_frame_register (struct frame_info
*frame
, int regnum
, const void *buf
)
717 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
722 frame_register (frame
, regnum
, &optim
, &lval
, &addr
, &realnum
, NULL
);
724 error ("Attempt to assign to a value that was optimized out.");
729 /* FIXME: write_memory doesn't yet take constant buffers.
731 char tmp
[MAX_REGISTER_SIZE
];
732 memcpy (tmp
, buf
, register_size (gdbarch
, regnum
));
733 write_memory (addr
, tmp
, register_size (gdbarch
, regnum
));
737 regcache_cooked_write (current_regcache
, realnum
, buf
);
740 error ("Attempt to assign to an unmodifiable value.");
744 /* frame_register_read ()
746 Find and return the value of REGNUM for the specified stack frame.
747 The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
749 Returns 0 if the register value could not be found. */
752 frame_register_read (struct frame_info
*frame
, int regnum
, void *myaddr
)
758 frame_register (frame
, regnum
, &optimized
, &lval
, &addr
, &realnum
, myaddr
);
760 /* FIXME: cagney/2002-05-15: This test, is just bogus.
762 It indicates that the target failed to supply a value for a
763 register because it was "not available" at this time. Problem
764 is, the target still has the register and so get saved_register()
765 may be returning a value saved on the stack. */
767 if (register_cached (regnum
) < 0)
768 return 0; /* register value not available */
774 /* Map between a frame register number and its name. A frame register
775 space is a superset of the cooked register space --- it also
776 includes builtin registers. */
779 frame_map_name_to_regnum (struct frame_info
*frame
, const char *name
, int len
)
781 return user_reg_map_name_to_regnum (get_frame_arch (frame
), name
, len
);
785 frame_map_regnum_to_name (struct frame_info
*frame
, int regnum
)
787 return user_reg_map_regnum_to_name (get_frame_arch (frame
), regnum
);
790 /* Create a sentinel frame. */
792 static struct frame_info
*
793 create_sentinel_frame (struct regcache
*regcache
)
795 struct frame_info
*frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
796 frame
->type
= NORMAL_FRAME
;
798 /* Explicitly initialize the sentinel frame's cache. Provide it
799 with the underlying regcache. In the future additional
800 information, such as the frame's thread will be added. */
801 frame
->prologue_cache
= sentinel_frame_cache (regcache
);
802 /* For the moment there is only one sentinel frame implementation. */
803 frame
->unwind
= sentinel_frame_unwind
;
804 /* Link this frame back to itself. The frame is self referential
805 (the unwound PC is the same as the pc), so make it so. */
807 /* Make the sentinel frame's ID valid, but invalid. That way all
808 comparisons with it should fail. */
809 frame
->this_id
.p
= 1;
810 frame
->this_id
.value
= null_frame_id
;
813 fprintf_unfiltered (gdb_stdlog
, "{ create_sentinel_frame (...) -> ");
814 fprint_frame (gdb_stdlog
, frame
);
815 fprintf_unfiltered (gdb_stdlog
, " }\n");
820 /* Info about the innermost stack frame (contents of FP register) */
822 static struct frame_info
*current_frame
;
824 /* Cache for frame addresses already read by gdb. Valid only while
825 inferior is stopped. Control variables for the frame cache should
826 be local to this module. */
828 static struct obstack frame_cache_obstack
;
831 frame_obstack_zalloc (unsigned long size
)
833 void *data
= obstack_alloc (&frame_cache_obstack
, size
);
834 memset (data
, 0, size
);
839 frame_saved_regs_zalloc (struct frame_info
*fi
)
841 fi
->saved_regs
= (CORE_ADDR
*)
842 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
843 return fi
->saved_regs
;
847 deprecated_get_frame_saved_regs (struct frame_info
*fi
)
849 return fi
->saved_regs
;
852 /* Return the innermost (currently executing) stack frame. This is
853 split into two functions. The function unwind_to_current_frame()
854 is wrapped in catch exceptions so that, even when the unwind of the
855 sentinel frame fails, the function still returns a stack frame. */
858 unwind_to_current_frame (struct ui_out
*ui_out
, void *args
)
860 struct frame_info
*frame
= get_prev_frame (args
);
861 /* A sentinel frame can fail to unwind, eg, because it's PC value
862 lands in somewhere like start. */
865 current_frame
= frame
;
870 get_current_frame (void)
872 /* First check, and report, the lack of registers. Having GDB
873 report "No stack!" or "No memory" when the target doesn't even
874 have registers is very confusing. Besides, "printcmd.exp"
875 explicitly checks that ``print $pc'' with no registers prints "No
877 if (!target_has_registers
)
878 error ("No registers.");
879 if (!target_has_stack
)
881 if (!target_has_memory
)
882 error ("No memory.");
883 if (current_frame
== NULL
)
885 struct frame_info
*sentinel_frame
=
886 create_sentinel_frame (current_regcache
);
887 if (catch_exceptions (uiout
, unwind_to_current_frame
, sentinel_frame
,
888 NULL
, RETURN_MASK_ERROR
) != 0)
890 /* Oops! Fake a current frame? Is this useful? It has a PC
891 of zero, for instance. */
892 current_frame
= sentinel_frame
;
895 return current_frame
;
898 /* The "selected" stack frame is used by default for local and arg
899 access. May be zero, for no selected frame. */
901 struct frame_info
*deprecated_selected_frame
;
903 /* Return the selected frame. Always non-null (unless there isn't an
904 inferior sufficient for creating a frame) in which case an error is
908 get_selected_frame (void)
910 if (deprecated_selected_frame
== NULL
)
911 /* Hey! Don't trust this. It should really be re-finding the
912 last selected frame of the currently selected thread. This,
913 though, is better than nothing. */
914 select_frame (get_current_frame ());
915 /* There is always a frame. */
916 gdb_assert (deprecated_selected_frame
!= NULL
);
917 return deprecated_selected_frame
;
920 /* This is a variant of get_selected_frame which can be called when
921 the inferior does not have a frame; in that case it will return
922 NULL instead of calling error (). */
925 deprecated_safe_get_selected_frame (void)
927 if (!target_has_registers
|| !target_has_stack
|| !target_has_memory
)
929 return get_selected_frame ();
932 /* Select frame FI (or NULL - to invalidate the current frame). */
935 select_frame (struct frame_info
*fi
)
939 deprecated_selected_frame
= fi
;
940 /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
941 frame is being invalidated. */
942 if (selected_frame_level_changed_hook
)
943 selected_frame_level_changed_hook (frame_relative_level (fi
));
945 /* FIXME: kseitz/2002-08-28: It would be nice to call
946 selected_frame_level_changed_event right here, but due to limitations
947 in the current interfaces, we would end up flooding UIs with events
948 because select_frame is used extensively internally.
950 Once we have frame-parameterized frame (and frame-related) commands,
951 the event notification can be moved here, since this function will only
952 be called when the users selected frame is being changed. */
954 /* Ensure that symbols for this frame are read in. Also, determine the
955 source language of this frame, and switch to it if desired. */
958 s
= find_pc_symtab (get_frame_pc (fi
));
960 && s
->language
!= current_language
->la_language
961 && s
->language
!= language_unknown
962 && language_mode
== language_mode_auto
)
964 set_language (s
->language
);
969 /* Return the register saved in the simplistic ``saved_regs'' cache.
970 If the value isn't here AND a value is needed, try the next inner
974 legacy_saved_regs_prev_register (struct frame_info
*next_frame
,
975 void **this_prologue_cache
,
976 int regnum
, int *optimizedp
,
977 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
978 int *realnump
, void *bufferp
)
980 /* HACK: New code is passed the next frame and this cache.
981 Unfortunatly, old code expects this frame. Since this is a
982 backward compatibility hack, cheat by walking one level along the
983 prologue chain to the frame the old code expects.
985 Do not try this at home. Professional driver, closed course. */
986 struct frame_info
*frame
= next_frame
->prev
;
987 gdb_assert (frame
!= NULL
);
989 if (deprecated_get_frame_saved_regs (frame
) == NULL
)
991 /* If nothing's initialized the saved regs, do it now. */
992 gdb_assert (DEPRECATED_FRAME_INIT_SAVED_REGS_P ());
993 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
994 gdb_assert (deprecated_get_frame_saved_regs (frame
) != NULL
);
997 if (deprecated_get_frame_saved_regs (frame
) != NULL
998 && deprecated_get_frame_saved_regs (frame
)[regnum
] != 0)
1000 if (regnum
== SP_REGNUM
)
1002 /* SP register treated specially. */
1007 if (bufferp
!= NULL
)
1008 /* NOTE: cagney/2003-05-09: In-lined store_address with
1009 it's body - store_unsigned_integer. */
1010 store_unsigned_integer (bufferp
, REGISTER_RAW_SIZE (regnum
),
1011 deprecated_get_frame_saved_regs (frame
)[regnum
]);
1015 /* Any other register is saved in memory, fetch it but cache
1016 a local copy of its value. */
1018 *lvalp
= lval_memory
;
1019 *addrp
= deprecated_get_frame_saved_regs (frame
)[regnum
];
1021 if (bufferp
!= NULL
)
1024 /* Save each register value, as it is read in, in a
1025 frame based cache. */
1026 void **regs
= (*this_prologue_cache
);
1029 int sizeof_cache
= ((NUM_REGS
+ NUM_PSEUDO_REGS
)
1031 regs
= frame_obstack_zalloc (sizeof_cache
);
1032 (*this_prologue_cache
) = regs
;
1034 if (regs
[regnum
] == NULL
)
1037 = frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum
));
1038 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], regs
[regnum
],
1039 REGISTER_RAW_SIZE (regnum
));
1041 memcpy (bufferp
, regs
[regnum
], REGISTER_RAW_SIZE (regnum
));
1043 /* Read the value in from memory. */
1044 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], bufferp
,
1045 REGISTER_RAW_SIZE (regnum
));
1052 /* No luck. Assume this and the next frame have the same register
1053 value. Pass the unwind request down the frame chain to the next
1054 frame. Hopefully that frame will find the register's location. */
1055 frame_register_unwind (next_frame
, regnum
, optimizedp
, lvalp
, addrp
,
1060 legacy_saved_regs_this_id (struct frame_info
*next_frame
,
1061 void **this_prologue_cache
,
1062 struct frame_id
*id
)
1064 /* legacy_get_prev_frame() always sets ->this_id.p, hence this is
1066 internal_error (__FILE__
, __LINE__
, "legacy_saved_regs_this_id() called");
1069 const struct frame_unwind legacy_saved_regs_unwinder
= {
1070 /* Not really. It gets overridden by legacy_get_prev_frame. */
1072 legacy_saved_regs_this_id
,
1073 legacy_saved_regs_prev_register
1075 const struct frame_unwind
*legacy_saved_regs_unwind
= &legacy_saved_regs_unwinder
;
1078 /* Function: deprecated_generic_get_saved_register
1079 Find register number REGNUM relative to FRAME and put its (raw,
1080 target format) contents in *RAW_BUFFER.
1082 Set *OPTIMIZED if the variable was optimized out (and thus can't be
1083 fetched). Note that this is never set to anything other than zero
1084 in this implementation.
1086 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
1087 whether the value was fetched from memory, from a register, or in a
1088 strange and non-modifiable way (e.g. a frame pointer which was
1089 calculated rather than fetched). We will use not_lval for values
1090 fetched from generic dummy frames.
1092 Set *ADDRP to the address, either in memory or as a
1093 DEPRECATED_REGISTER_BYTE offset into the registers array. If the
1094 value is stored in a dummy frame, set *ADDRP to zero.
1096 The argument RAW_BUFFER must point to aligned memory. */
1099 deprecated_generic_get_saved_register (char *raw_buffer
, int *optimized
,
1101 struct frame_info
*frame
, int regnum
,
1102 enum lval_type
*lval
)
1104 if (!target_has_registers
)
1105 error ("No registers.");
1107 /* Normal systems don't optimize out things with register numbers. */
1108 if (optimized
!= NULL
)
1111 if (addrp
) /* default assumption: not found in memory */
1114 /* Note: since the current frame's registers could only have been
1115 saved by frames INTERIOR TO the current frame, we skip examining
1116 the current frame itself: otherwise, we would be getting the
1117 previous frame's registers which were saved by the current frame. */
1121 for (frame
= get_next_frame (frame
);
1122 frame_relative_level (frame
) >= 0;
1123 frame
= get_next_frame (frame
))
1125 if (get_frame_type (frame
) == DUMMY_FRAME
)
1127 if (lval
) /* found it in a CALL_DUMMY frame */
1130 /* FIXME: cagney/2002-06-26: This should be via the
1131 gdbarch_register_read() method so that it, on the
1132 fly, constructs either a raw or pseudo register
1133 from the raw register cache. */
1135 (deprecated_find_dummy_frame_regcache (get_frame_pc (frame
),
1136 get_frame_base (frame
)),
1137 regnum
, raw_buffer
);
1141 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
1142 if (deprecated_get_frame_saved_regs (frame
) != NULL
1143 && deprecated_get_frame_saved_regs (frame
)[regnum
] != 0)
1145 if (lval
) /* found it saved on the stack */
1146 *lval
= lval_memory
;
1147 if (regnum
== SP_REGNUM
)
1149 if (raw_buffer
) /* SP register treated specially */
1150 /* NOTE: cagney/2003-05-09: In-line store_address
1151 with it's body - store_unsigned_integer. */
1152 store_unsigned_integer (raw_buffer
,
1153 REGISTER_RAW_SIZE (regnum
),
1154 deprecated_get_frame_saved_regs (frame
)[regnum
]);
1158 if (addrp
) /* any other register */
1159 *addrp
= deprecated_get_frame_saved_regs (frame
)[regnum
];
1161 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], raw_buffer
,
1162 REGISTER_RAW_SIZE (regnum
));
1169 /* If we get thru the loop to this point, it means the register was
1170 not saved in any frame. Return the actual live-register value. */
1172 if (lval
) /* found it in a live register */
1173 *lval
= lval_register
;
1175 *addrp
= DEPRECATED_REGISTER_BYTE (regnum
);
1177 deprecated_read_register_gen (regnum
, raw_buffer
);
1180 /* Determine the frame's type based on its PC. */
1182 static enum frame_type
1183 frame_type_from_pc (CORE_ADDR pc
)
1185 /* FIXME: cagney/2002-11-24: Can't yet directly call
1186 pc_in_dummy_frame() as some architectures don't set
1187 PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the
1188 latter is implemented by simply calling pc_in_dummy_frame). */
1189 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1190 && DEPRECATED_PC_IN_CALL_DUMMY (pc
, 0, 0))
1195 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
1196 if (PC_IN_SIGTRAMP (pc
, name
))
1197 return SIGTRAMP_FRAME
;
1199 return NORMAL_FRAME
;
1203 /* Create an arbitrary (i.e. address specified by user) or innermost frame.
1204 Always returns a non-NULL value. */
1207 create_new_frame (CORE_ADDR addr
, CORE_ADDR pc
)
1209 struct frame_info
*fi
;
1213 fprintf_unfiltered (gdb_stdlog
,
1214 "{ create_new_frame (addr=0x%s, pc=0x%s) ",
1215 paddr_nz (addr
), paddr_nz (pc
));
1218 fi
= frame_obstack_zalloc (sizeof (struct frame_info
));
1220 fi
->next
= create_sentinel_frame (current_regcache
);
1222 /* Select/initialize both the unwind function and the frame's type
1224 fi
->unwind
= frame_unwind_find_by_frame (fi
->next
);
1225 if (fi
->unwind
->type
!= UNKNOWN_FRAME
)
1226 fi
->type
= fi
->unwind
->type
;
1228 fi
->type
= frame_type_from_pc (pc
);
1231 deprecated_update_frame_base_hack (fi
, addr
);
1232 deprecated_update_frame_pc_hack (fi
, pc
);
1234 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1235 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, fi
);
1239 fprintf_unfiltered (gdb_stdlog
, "-> ");
1240 fprint_frame (gdb_stdlog
, fi
);
1241 fprintf_unfiltered (gdb_stdlog
, " }\n");
1247 /* Return the frame that THIS_FRAME calls (NULL if THIS_FRAME is the
1248 innermost frame). Be careful to not fall off the bottom of the
1249 frame chain and onto the sentinel frame. */
1252 get_next_frame (struct frame_info
*this_frame
)
1254 if (this_frame
->level
> 0)
1255 return this_frame
->next
;
1261 deprecated_get_next_frame_hack (struct frame_info
*this_frame
)
1263 return this_frame
->next
;
1266 /* Flush the entire frame cache. */
1269 flush_cached_frames (void)
1271 /* Since we can't really be sure what the first object allocated was */
1272 obstack_free (&frame_cache_obstack
, 0);
1273 obstack_init (&frame_cache_obstack
);
1275 current_frame
= NULL
; /* Invalidate cache */
1276 select_frame (NULL
);
1277 annotate_frames_invalid ();
1279 fprintf_unfiltered (gdb_stdlog
, "{ flush_cached_frames () }\n");
1282 /* Flush the frame cache, and start a new one if necessary. */
1285 reinit_frame_cache (void)
1287 flush_cached_frames ();
1289 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
1290 if (PIDGET (inferior_ptid
) != 0)
1292 select_frame (get_current_frame ());
1296 /* Create the previous frame using the deprecated methods
1297 INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */
1299 static struct frame_info
*
1300 legacy_get_prev_frame (struct frame_info
*this_frame
)
1302 CORE_ADDR address
= 0;
1303 struct frame_info
*prev
;
1306 /* Don't frame_debug print legacy_get_prev_frame() here, just
1307 confuses the output. */
1309 /* Allocate the new frame.
1311 There is no reason to worry about memory leaks, should the
1312 remainder of the function fail. The allocated memory will be
1313 quickly reclaimed when the frame cache is flushed, and the `we've
1314 been here before' check, in get_prev_frame will stop repeated
1315 memory allocation calls. */
1316 prev
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
1317 prev
->level
= this_frame
->level
+ 1;
1319 /* Do not completly wire it in to the frame chain. Some (bad) code
1320 in INIT_FRAME_EXTRA_INFO tries to look along frame->prev to pull
1321 some fancy tricks (of course such code is, by definition,
1324 On the other hand, methods, such as get_frame_pc() and
1325 get_frame_base() rely on being able to walk along the frame
1326 chain. Make certain that at least they work by providing that
1327 link. Of course things manipulating prev can't go back. */
1328 prev
->next
= this_frame
;
1330 /* NOTE: cagney/2002-11-18: Should have been correctly setting the
1331 frame's type here, before anything else, and not last, at the
1332 bottom of this function. The various
1333 DEPRECATED_INIT_EXTRA_FRAME_INFO, DEPRECATED_INIT_FRAME_PC,
1334 DEPRECATED_INIT_FRAME_PC_FIRST and
1335 DEPRECATED_FRAME_INIT_SAVED_REGS methods are full of work-arounds
1336 that handle the frame not being correctly set from the start.
1337 Unfortunatly those same work-arounds rely on the type defaulting
1338 to NORMAL_FRAME. Ulgh! The new frame code does not have this
1340 prev
->type
= UNKNOWN_FRAME
;
1342 /* A legacy frame's ID is always computed here. Mark it as valid. */
1343 prev
->this_id
.p
= 1;
1345 /* Handle sentinel frame unwind as a special case. */
1346 if (this_frame
->level
< 0)
1348 /* Try to unwind the PC. If that doesn't work, assume we've reached
1349 the oldest frame and simply return. Is there a better sentinal
1350 value? The unwound PC value is then used to initialize the new
1351 previous frame's type.
1353 Note that the pc-unwind is intentionally performed before the
1354 frame chain. This is ok since, for old targets, both
1355 frame_pc_unwind (nee, DEPRECATED_FRAME_SAVED_PC) and
1356 DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
1357 have already been initialized (using
1358 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1361 By unwinding the PC first, it becomes possible to, in the case of
1362 a dummy frame, avoid also unwinding the frame ID. This is
1363 because (well ignoring the PPC) a dummy frame can be located
1364 using THIS_FRAME's frame ID. */
1366 deprecated_update_frame_pc_hack (prev
, frame_pc_unwind (this_frame
));
1367 if (get_frame_pc (prev
) == 0)
1369 /* The allocated PREV_FRAME will be reclaimed when the frame
1370 obstack is next purged. */
1373 fprintf_unfiltered (gdb_stdlog
, "-> ");
1374 fprint_frame (gdb_stdlog
, NULL
);
1375 fprintf_unfiltered (gdb_stdlog
,
1376 " // unwound legacy PC zero }\n");
1381 /* Set the unwind functions based on that identified PC. Ditto
1382 for the "type" but strongly prefer the unwinder's frame type. */
1383 prev
->unwind
= frame_unwind_find_by_frame (prev
->next
);
1384 if (prev
->unwind
->type
== UNKNOWN_FRAME
)
1385 prev
->type
= frame_type_from_pc (get_frame_pc (prev
));
1387 prev
->type
= prev
->unwind
->type
;
1389 /* Find the prev's frame's ID. */
1390 if (prev
->type
== DUMMY_FRAME
1391 && gdbarch_unwind_dummy_id_p (current_gdbarch
))
1393 /* When unwinding a normal frame, the stack structure is
1394 determined by analyzing the frame's function's code (be
1395 it using brute force prologue analysis, or the dwarf2
1396 CFI). In the case of a dummy frame, that simply isn't
1397 possible. The The PC is either the program entry point,
1398 or some random address on the stack. Trying to use that
1399 PC to apply standard frame ID unwind techniques is just
1400 asking for trouble. */
1401 /* Use an architecture specific method to extract the prev's
1402 dummy ID from the next frame. Note that this method uses
1403 frame_register_unwind to obtain the register values
1404 needed to determine the dummy frame's ID. */
1405 prev
->this_id
.value
= gdbarch_unwind_dummy_id (current_gdbarch
,
1410 /* We're unwinding a sentinel frame, the PC of which is
1411 pointing at a stack dummy. Fake up the dummy frame's ID
1412 using the same sequence as is found a traditional
1413 unwinder. Once all architectures supply the
1414 unwind_dummy_id method, this code can go away. */
1415 prev
->this_id
.value
= frame_id_build (deprecated_read_fp (),
1419 /* Check that the unwound ID is valid. */
1420 if (!frame_id_p (prev
->this_id
.value
))
1424 fprintf_unfiltered (gdb_stdlog
, "-> ");
1425 fprint_frame (gdb_stdlog
, NULL
);
1426 fprintf_unfiltered (gdb_stdlog
,
1427 " // unwound legacy ID invalid }\n");
1432 /* Check that the new frame isn't inner to (younger, below,
1433 next) the old frame. If that happens the frame unwind is
1435 /* FIXME: cagney/2003-02-25: Ignore the sentinel frame since
1436 that doesn't have a valid frame ID. Should instead set the
1437 sentinel frame's frame ID to a `sentinel'. Leave it until
1438 after the switch to storing the frame ID, instead of the
1439 frame base, in the frame object. */
1442 this_frame
->prev
= prev
;
1444 /* FIXME: cagney/2002-01-19: This call will go away. Instead of
1445 initializing extra info, all frames will use the frame_cache
1446 (passed to the unwind functions) to store additional frame
1447 info. Unfortunatly legacy targets can't use
1448 legacy_get_prev_frame() to unwind the sentinel frame and,
1449 consequently, are forced to take this code path and rely on
1450 the below call to DEPRECATED_INIT_EXTRA_FRAME_INFO to
1451 initialize the inner-most frame. */
1452 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1454 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, prev
);
1457 if (prev
->type
== NORMAL_FRAME
)
1458 prev
->this_id
.value
.code_addr
1459 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1463 fprintf_unfiltered (gdb_stdlog
, "-> ");
1464 fprint_frame (gdb_stdlog
, prev
);
1465 fprintf_unfiltered (gdb_stdlog
, " } // legacy innermost frame\n");
1470 /* This code only works on normal frames. A sentinel frame, where
1471 the level is -1, should never reach this code. */
1472 gdb_assert (this_frame
->level
>= 0);
1474 /* On some machines it is possible to call a function without
1475 setting up a stack frame for it. On these machines, we
1476 define this macro to take two args; a frameinfo pointer
1477 identifying a frame and a variable to set or clear if it is
1478 or isn't leafless. */
1480 /* Still don't want to worry about this except on the innermost
1481 frame. This macro will set FROMLEAF if THIS_FRAME is a frameless
1482 function invocation. */
1483 if (this_frame
->level
== 0)
1484 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
1485 the frame chain, not just the inner most frame! The generic,
1486 per-architecture, frame code should handle this and the below
1487 should simply be removed. */
1488 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (this_frame
);
1493 /* A frameless inner-most frame. The `FP' (which isn't an
1494 architecture frame-pointer register!) of the caller is the same
1496 /* FIXME: 2002-11-09: There isn't any reason to special case this
1497 edge condition. Instead the per-architecture code should hande
1499 /* FIXME: cagney/2003-06-16: This returns the inner most stack
1500 address for the previous frame, that, however, is wrong. It
1501 should be the inner most stack address for the previous to
1502 previous frame. This is because it is the previous to previous
1503 frame's innermost stack address that is constant through out
1504 the lifetime of the previous frame (trust me :-). */
1505 address
= get_frame_base (this_frame
);
1508 /* Two macros defined in tm.h specify the machine-dependent
1509 actions to be performed here.
1511 First, get the frame's chain-pointer.
1513 If that is zero, the frame is the outermost frame or a leaf
1514 called by the outermost frame. This means that if start
1515 calls main without a frame, we'll return 0 (which is fine
1518 Nope; there's a problem. This also returns when the current
1519 routine is a leaf of main. This is unacceptable. We move
1520 this to after the ffi test; I'd rather have backtraces from
1521 start go curfluy than have an abort called from main not show
1523 if (DEPRECATED_FRAME_CHAIN_P ())
1524 address
= DEPRECATED_FRAME_CHAIN (this_frame
);
1527 /* Someone is part way through coverting an old architecture
1528 to the new frame code. Implement FRAME_CHAIN the way the
1530 /* Find PREV frame's unwinder. */
1531 prev
->unwind
= frame_unwind_find_by_frame (this_frame
->next
);
1532 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
1533 type in the frame, the unwinder's type should be returned
1534 directly. Unfortunatly, legacy code, called by
1535 legacy_get_prev_frame, explicitly set the frames type
1536 using the method deprecated_set_frame_type(). */
1537 prev
->type
= prev
->unwind
->type
;
1538 /* Find PREV frame's ID. */
1539 prev
->unwind
->this_id (this_frame
,
1540 &prev
->prologue_cache
,
1541 &prev
->this_id
.value
);
1542 prev
->this_id
.p
= 1;
1543 address
= prev
->this_id
.value
.stack_addr
;
1546 if (!legacy_frame_chain_valid (address
, this_frame
))
1550 fprintf_unfiltered (gdb_stdlog
, "-> ");
1551 fprint_frame (gdb_stdlog
, NULL
);
1552 fprintf_unfiltered (gdb_stdlog
,
1553 " // legacy frame chain invalid }\n");
1562 fprintf_unfiltered (gdb_stdlog
, "-> ");
1563 fprint_frame (gdb_stdlog
, NULL
);
1564 fprintf_unfiltered (gdb_stdlog
,
1565 " // legacy frame chain NULL }\n");
1570 /* Link in the already allocated prev frame. */
1571 this_frame
->prev
= prev
;
1572 deprecated_update_frame_base_hack (prev
, address
);
1574 /* This change should not be needed, FIXME! We should determine
1575 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1576 after DEPRECATED_INIT_EXTRA_FRAME_INFO and come up with a simple
1577 way to express what goes on here.
1579 DEPRECATED_INIT_EXTRA_FRAME_INFO is called from two places:
1580 create_new_frame (where the PC is already set up) and here (where
1581 it isn't). DEPRECATED_INIT_FRAME_PC is only called from here,
1582 always after DEPRECATED_INIT_EXTRA_FRAME_INFO.
1584 The catch is the MIPS, where DEPRECATED_INIT_EXTRA_FRAME_INFO
1585 requires the PC value (which hasn't been set yet). Some other
1586 machines appear to require DEPRECATED_INIT_EXTRA_FRAME_INFO
1587 before they can do DEPRECATED_INIT_FRAME_PC. Phoo.
1589 We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
1590 complication to an already overcomplicated part of GDB.
1591 gnu@cygnus.com, 15Sep92.
1593 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
1594 DEPRECATED_INIT_EXTRA_FRAME_INFO, one possible scheme:
1596 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1597 (deprecated_read_fp ()), read_pc ()). Machines with extra frame
1598 info would do that (or the local equivalent) and then set the
1601 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1602 create_new_frame would no longer init extra frame info;
1603 SETUP_ARBITRARY_FRAME would have to do that.
1605 INIT_PREV_FRAME(fromleaf, prev) Replace
1606 DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC.
1607 This should also return a flag saying whether to keep the new
1608 frame, or whether to discard it, because on some machines (e.g.
1609 mips) it is really awkward to have DEPRECATED_FRAME_CHAIN_VALID
1610 called BEFORE DEPRECATED_INIT_EXTRA_FRAME_INFO (there is no good
1611 way to get information deduced in DEPRECATED_FRAME_CHAIN_VALID
1612 into the extra fields of the new frame). std_frame_pc(fromleaf,
1615 This is the default setting for INIT_PREV_FRAME. It just does
1616 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1617 will call it from INIT_PREV_FRAME (either at the beginning, the
1618 end, or in the middle). Some machines won't use it.
1620 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1622 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1623 reason for things to be this complicated.
1625 The trick is to assume that there is always a frame. Instead of
1626 special casing the inner-most frame, create fake frame
1627 (containing the hardware registers) that is inner to the
1628 user-visible inner-most frame (...) and then unwind from that.
1629 That way architecture code can use use the standard
1630 frame_XX_unwind() functions and not differentiate between the
1631 inner most and any other case.
1633 Since there is always a frame to unwind from, there is always
1634 somewhere (THIS_FRAME) to store all the info needed to construct
1635 a new (previous) frame without having to first create it. This
1636 means that the convolution below - needing to carefully order a
1637 frame's initialization - isn't needed.
1639 The irony here though, is that DEPRECATED_FRAME_CHAIN(), at least
1640 for a more up-to-date architecture, always calls
1641 FRAME_SAVED_PC(), and FRAME_SAVED_PC() computes the PC but
1642 without first needing the frame! Instead of the convolution
1643 below, we could have simply called FRAME_SAVED_PC() and been done
1644 with it! Note that FRAME_SAVED_PC() is being superseed by
1645 frame_pc_unwind() and that function does have somewhere to cache
1648 if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
1649 deprecated_update_frame_pc_hack (prev
,
1650 DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf
,
1653 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1654 DEPRECATED_INIT_EXTRA_FRAME_INFO (fromleaf
, prev
);
1656 /* This entry is in the frame queue now, which is good since
1657 FRAME_SAVED_PC may use that queue to figure out its value (see
1658 tm-sparc.h). We want the pc saved in the inferior frame. */
1659 if (DEPRECATED_INIT_FRAME_PC_P ())
1660 deprecated_update_frame_pc_hack (prev
,
1661 DEPRECATED_INIT_FRAME_PC (fromleaf
,
1664 /* If ->frame and ->pc are unchanged, we are in the process of
1665 getting ourselves into an infinite backtrace. Some architectures
1666 check this in DEPRECATED_FRAME_CHAIN or thereabouts, but it seems
1667 like there is no reason this can't be an architecture-independent
1669 if (get_frame_base (prev
) == get_frame_base (this_frame
)
1670 && get_frame_pc (prev
) == get_frame_pc (this_frame
))
1672 this_frame
->prev
= NULL
;
1673 obstack_free (&frame_cache_obstack
, prev
);
1676 fprintf_unfiltered (gdb_stdlog
, "-> ");
1677 fprint_frame (gdb_stdlog
, NULL
);
1678 fprintf_unfiltered (gdb_stdlog
,
1679 " // legacy this.id == prev.id }\n");
1684 /* Initialize the code used to unwind the frame PREV based on the PC
1685 (and probably other architectural information). The PC lets you
1686 check things like the debug info at that point (dwarf2cfi?) and
1687 use that to decide how the frame should be unwound.
1689 If there isn't a FRAME_CHAIN, the code above will have already
1691 if (prev
->unwind
== NULL
)
1692 prev
->unwind
= frame_unwind_find_by_frame (prev
->next
);
1694 /* If the unwinder provides a frame type, use it. Otherwize
1695 continue on to that heuristic mess. */
1696 if (prev
->unwind
->type
!= UNKNOWN_FRAME
)
1698 prev
->type
= prev
->unwind
->type
;
1699 if (prev
->type
== NORMAL_FRAME
)
1700 /* FIXME: cagney/2003-06-16: would get_frame_pc() be better? */
1701 prev
->this_id
.value
.code_addr
1702 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1705 fprintf_unfiltered (gdb_stdlog
, "-> ");
1706 fprint_frame (gdb_stdlog
, prev
);
1707 fprintf_unfiltered (gdb_stdlog
, " } // legacy with unwound type\n");
1712 /* NOTE: cagney/2002-11-18: The code segments, found in
1713 create_new_frame and get_prev_frame(), that initializes the
1714 frames type is subtly different. The latter only updates ->type
1715 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1716 get_prev_frame() overriding the frame's type when the INIT code
1717 has previously set it. This is really somewhat bogus. The
1718 initialization, as seen in create_new_frame(), should occur
1719 before the INIT function has been called. */
1720 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1721 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
1722 ? DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (prev
), 0, 0)
1723 : pc_in_dummy_frame (get_frame_pc (prev
))))
1724 prev
->type
= DUMMY_FRAME
;
1727 /* FIXME: cagney/2002-11-10: This should be moved to before the
1728 INIT code above so that the INIT code knows what the frame's
1729 type is (in fact, for a [generic] dummy-frame, the type can
1730 be set and then the entire initialization can be skipped.
1731 Unforunatly, its the INIT code that sets the PC (Hmm, catch
1734 find_pc_partial_function (get_frame_pc (prev
), &name
, NULL
, NULL
);
1735 if (PC_IN_SIGTRAMP (get_frame_pc (prev
), name
))
1736 prev
->type
= SIGTRAMP_FRAME
;
1737 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1738 architectures are forcing the frame's type in INIT so we
1739 don't want to override it here. Remember, NORMAL_FRAME == 0,
1740 so it all works (just :-/). Once this initialization is
1741 moved to the start of this function, all this nastness will
1745 if (prev
->type
== NORMAL_FRAME
)
1746 prev
->this_id
.value
.code_addr
1747 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1751 fprintf_unfiltered (gdb_stdlog
, "-> ");
1752 fprint_frame (gdb_stdlog
, prev
);
1753 fprintf_unfiltered (gdb_stdlog
, " } // legacy with confused type\n");
1759 /* Return a structure containing various interesting information
1760 about the frame that called THIS_FRAME. Returns NULL
1761 if there is no such frame. */
1764 get_prev_frame (struct frame_info
*this_frame
)
1766 struct frame_info
*prev_frame
;
1770 fprintf_unfiltered (gdb_stdlog
, "{ get_prev_frame (this_frame=");
1771 if (this_frame
!= NULL
)
1772 fprintf_unfiltered (gdb_stdlog
, "%d", this_frame
->level
);
1774 fprintf_unfiltered (gdb_stdlog
, "<NULL>");
1775 fprintf_unfiltered (gdb_stdlog
, ") ");
1778 /* Return the inner-most frame, when the caller passes in NULL. */
1779 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
1780 caller should have previously obtained a valid frame using
1781 get_selected_frame() and then called this code - only possibility
1782 I can think of is code behaving badly.
1784 NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
1785 block_innermost_frame(). It does the sequence: frame = NULL;
1786 while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
1787 it couldn't be written better, I don't know.
1789 NOTE: cagney/2003-01-11: I suspect what is happening is
1790 block_innermost_frame() is, when the target has no state
1791 (registers, memory, ...), still calling this function. The
1792 assumption being that this function will return NULL indicating
1793 that a frame isn't possible, rather than checking that the target
1794 has state and then calling get_current_frame() and
1795 get_prev_frame(). This is a guess mind. */
1796 if (this_frame
== NULL
)
1798 /* NOTE: cagney/2002-11-09: There was a code segment here that
1799 would error out when CURRENT_FRAME was NULL. The comment
1800 that went with it made the claim ...
1802 ``This screws value_of_variable, which just wants a nice
1803 clean NULL return from block_innermost_frame if there are no
1804 frames. I don't think I've ever seen this message happen
1805 otherwise. And returning NULL here is a perfectly legitimate
1808 Per the above, this code shouldn't even be called with a NULL
1810 return current_frame
;
1813 /* There is always a frame. If this assertion fails, suspect that
1814 something should be calling get_selected_frame() or
1815 get_current_frame(). */
1816 gdb_assert (this_frame
!= NULL
);
1818 if (this_frame
->level
>= 0
1819 && !backtrace_past_main
1820 && inside_main_func (get_frame_pc (this_frame
)))
1821 /* Don't unwind past main(), bug always unwind the sentinel frame.
1822 Note, this is done _before_ the frame has been marked as
1823 previously unwound. That way if the user later decides to
1824 allow unwinds past main(), that just happens. */
1827 fprintf_unfiltered (gdb_stdlog
, "-> NULL // inside main func }\n");
1831 if (this_frame
->level
> backtrace_limit
)
1833 error ("Backtrace limit of %d exceeded", backtrace_limit
);
1836 /* If we're already inside the entry function for the main objfile,
1837 then it isn't valid. Don't apply this test to a dummy frame -
1838 dummy frame PC's typically land in the entry func. Don't apply
1839 this test to the sentinel frame. Sentinel frames should always
1840 be allowed to unwind. */
1841 /* NOTE: cagney/2003-02-25: Don't enable until someone has found
1842 hard evidence that this is needed. */
1843 /* NOTE: cagney/2003-07-07: Fixed a bug in inside_main_func - wasn't
1844 checking for "main" in the minimal symbols. With that fixed
1845 asm-source tests now stop in "main" instead of halting the
1846 backtrace in wierd and wonderful ways somewhere inside the entry
1847 file. Suspect that deprecated_inside_entry_file and
1848 inside_entry_func tests were added to work around that (now
1850 /* NOTE: cagney/2003-07-15: danielj (if I'm reading it right)
1851 suggested having the inside_entry_func test use the
1852 inside_main_func msymbol trick (along with entry_point_address I
1853 guess) to determine the address range of the start function.
1854 That should provide a far better stopper than the current
1856 /* NOTE: cagney/2003-07-15: Need to add a "set backtrace
1857 beyond-entry-func" command so that this can be selectively
1861 && backtrace_beyond_entry_func
1863 && this_frame
->type
!= DUMMY_FRAME
&& this_frame
->level
>= 0
1864 && inside_entry_func (get_frame_pc (this_frame
)))
1868 fprintf_unfiltered (gdb_stdlog
, "-> ");
1869 fprint_frame (gdb_stdlog
, NULL
);
1870 fprintf_unfiltered (gdb_stdlog
, "// inside entry func }\n");
1875 /* Only try to do the unwind once. */
1876 if (this_frame
->prev_p
)
1880 fprintf_unfiltered (gdb_stdlog
, "-> ");
1881 fprint_frame (gdb_stdlog
, this_frame
->prev
);
1882 fprintf_unfiltered (gdb_stdlog
, " // cached \n");
1884 return this_frame
->prev
;
1886 this_frame
->prev_p
= 1;
1888 /* If we're inside the entry file, it isn't valid. Don't apply this
1889 test to a dummy frame - dummy frame PC's typically land in the
1890 entry file. Don't apply this test to the sentinel frame.
1891 Sentinel frames should always be allowed to unwind. */
1892 /* NOTE: drow/2002-12-25: should there be a way to disable this
1893 check? It assumes a single small entry file, and the way some
1894 debug readers (e.g. dbxread) figure out which object is the
1895 entry file is somewhat hokey. */
1896 /* NOTE: cagney/2003-01-10: If there is a way of disabling this test
1897 then it should probably be moved to before the ->prev_p test,
1899 /* NOTE: vinschen/2003-04-01: Disabled. It turns out that the call
1900 to deprecated_inside_entry_file destroys a meaningful backtrace
1901 under some conditions. E. g. the backtrace tests in the
1902 asm-source testcase are broken for some targets. In this test
1903 the functions are all implemented as part of one file and the
1904 testcase is not necessarily linked with a start file (depending
1905 on the target). What happens is, that the first frame is printed
1906 normaly and following frames are treated as being inside the
1907 enttry file then. This way, only the #0 frame is printed in the
1908 backtrace output. */
1910 && this_frame
->type
!= DUMMY_FRAME
&& this_frame
->level
>= 0
1911 && deprecated_inside_entry_file (get_frame_pc (this_frame
)))
1915 fprintf_unfiltered (gdb_stdlog
, "-> ");
1916 fprint_frame (gdb_stdlog
, NULL
);
1917 fprintf_unfiltered (gdb_stdlog
, " // inside entry file }\n");
1922 /* If any of the old frame initialization methods are around, use
1923 the legacy get_prev_frame method. */
1924 if (legacy_frame_p (current_gdbarch
))
1926 prev_frame
= legacy_get_prev_frame (this_frame
);
1930 /* Check that this frame's ID was valid. If it wasn't, don't try to
1931 unwind to the prev frame. Be careful to not apply this test to
1932 the sentinel frame. */
1933 if (this_frame
->level
>= 0 && !frame_id_p (get_frame_id (this_frame
)))
1937 fprintf_unfiltered (gdb_stdlog
, "-> ");
1938 fprint_frame (gdb_stdlog
, NULL
);
1939 fprintf_unfiltered (gdb_stdlog
, " // this ID is NULL }\n");
1944 /* Check that this frame's ID isn't inner to (younger, below, next)
1945 the next frame. This happens when a frame unwind goes backwards.
1946 Since the sentinel frame doesn't really exist, don't compare the
1947 inner-most against that sentinel. */
1948 if (this_frame
->level
> 0
1949 && frame_id_inner (get_frame_id (this_frame
),
1950 get_frame_id (this_frame
->next
)))
1951 error ("Previous frame inner to this frame (corrupt stack?)");
1953 /* Check that this and the next frame are not identical. If they
1954 are, there is most likely a stack cycle. As with the inner-than
1955 test above, avoid comparing the inner-most and sentinel frames. */
1956 if (this_frame
->level
> 0
1957 && frame_id_eq (get_frame_id (this_frame
),
1958 get_frame_id (this_frame
->next
)))
1959 error ("Previous frame identical to this frame (corrupt stack?)");
1961 /* Allocate the new frame but do not wire it in to the frame chain.
1962 Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
1963 frame->next to pull some fancy tricks (of course such code is, by
1964 definition, recursive). Try to prevent it.
1966 There is no reason to worry about memory leaks, should the
1967 remainder of the function fail. The allocated memory will be
1968 quickly reclaimed when the frame cache is flushed, and the `we've
1969 been here before' check above will stop repeated memory
1970 allocation calls. */
1971 prev_frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
1972 prev_frame
->level
= this_frame
->level
+ 1;
1974 /* Try to unwind the PC. If that doesn't work, assume we've reached
1975 the oldest frame and simply return. Is there a better sentinal
1976 value? The unwound PC value is then used to initialize the new
1977 previous frame's type.
1979 Note that the pc-unwind is intentionally performed before the
1980 frame chain. This is ok since, for old targets, both
1981 frame_pc_unwind (nee, FRAME_SAVED_PC) and
1982 DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
1983 have already been initialized (using
1984 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1987 By unwinding the PC first, it becomes possible to, in the case of
1988 a dummy frame, avoid also unwinding the frame ID. This is
1989 because (well ignoring the PPC) a dummy frame can be located
1990 using THIS_FRAME's frame ID. */
1992 if (frame_pc_unwind (this_frame
) == 0)
1994 /* The allocated PREV_FRAME will be reclaimed when the frame
1995 obstack is next purged. */
1998 fprintf_unfiltered (gdb_stdlog
, "-> ");
1999 fprint_frame (gdb_stdlog
, NULL
);
2000 fprintf_unfiltered (gdb_stdlog
, " // unwound PC zero }\n");
2005 /* Don't yet compute ->unwind (and hence ->type). It is computed
2006 on-demand in get_frame_type, frame_register_unwind, and
2009 /* Don't yet compute the frame's ID. It is computed on-demand by
2012 /* The unwound frame ID is validate at the start of this function,
2013 as part of the logic to decide if that frame should be further
2014 unwound, and not here while the prev frame is being created.
2015 Doing this makes it possible for the user to examine a frame that
2016 has an invalid frame ID.
2018 Some very old VAX code noted: [...] For the sake of argument,
2019 suppose that the stack is somewhat trashed (which is one reason
2020 that "info frame" exists). So, return 0 (indicating we don't
2021 know the address of the arglist) if we don't know what frame this
2025 this_frame
->prev
= prev_frame
;
2026 prev_frame
->next
= this_frame
;
2030 fprintf_unfiltered (gdb_stdlog
, "-> ");
2031 fprint_frame (gdb_stdlog
, prev_frame
);
2032 fprintf_unfiltered (gdb_stdlog
, " }\n");
2039 get_frame_pc (struct frame_info
*frame
)
2041 gdb_assert (frame
->next
!= NULL
);
2042 return frame_pc_unwind (frame
->next
);
2045 /* Return an address of that falls within the frame's code block. */
2048 frame_unwind_address_in_block (struct frame_info
*next_frame
)
2050 /* A draft address. */
2051 CORE_ADDR pc
= frame_pc_unwind (next_frame
);
2053 /* If THIS frame is not inner most (i.e., NEXT isn't the sentinel),
2054 and NEXT is `normal' (i.e., not a sigtramp, dummy, ....) THIS
2055 frame's PC ends up pointing at the instruction fallowing the
2056 "call". Adjust that PC value so that it falls on the call
2057 instruction (which, hopefully, falls within THIS frame's code
2058 block. So far it's proved to be a very good approximation. See
2059 get_frame_type for why ->type can't be used. */
2060 if (next_frame
->level
>= 0
2061 && get_frame_type (next_frame
) == NORMAL_FRAME
)
2067 get_frame_address_in_block (struct frame_info
*this_frame
)
2069 return frame_unwind_address_in_block (this_frame
->next
);
2073 pc_notcurrent (struct frame_info
*frame
)
2075 /* If FRAME is not the innermost frame, that normally means that
2076 FRAME->pc points at the return instruction (which is *after* the
2077 call instruction), and we want to get the line containing the
2078 call (because the call is where the user thinks the program is).
2079 However, if the next frame is either a SIGTRAMP_FRAME or a
2080 DUMMY_FRAME, then the next frame will contain a saved interrupt
2081 PC and such a PC indicates the current (rather than next)
2082 instruction/line, consequently, for such cases, want to get the
2083 line containing fi->pc. */
2084 struct frame_info
*next
= get_next_frame (frame
);
2085 int notcurrent
= (next
!= NULL
&& get_frame_type (next
) == NORMAL_FRAME
);
2090 find_frame_sal (struct frame_info
*frame
, struct symtab_and_line
*sal
)
2092 (*sal
) = find_pc_line (get_frame_pc (frame
), pc_notcurrent (frame
));
2095 /* Per "frame.h", return the ``address'' of the frame. Code should
2096 really be using get_frame_id(). */
2098 get_frame_base (struct frame_info
*fi
)
2100 return get_frame_id (fi
).stack_addr
;
2103 /* High-level offsets into the frame. Used by the debug info. */
2106 get_frame_base_address (struct frame_info
*fi
)
2108 if (get_frame_type (fi
) != NORMAL_FRAME
)
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 return fi
->base
->this_base (fi
->next
, &fi
->prologue_cache
);
2116 return fi
->base
->this_base (fi
->next
, &fi
->base_cache
);
2120 get_frame_locals_address (struct frame_info
*fi
)
2123 if (get_frame_type (fi
) != NORMAL_FRAME
)
2125 /* If there isn't a frame address method, find it. */
2126 if (fi
->base
== NULL
)
2127 fi
->base
= frame_base_find_by_frame (fi
->next
);
2128 /* Sneaky: If the low-level unwind and high-level base code share a
2129 common unwinder, let them share the prologue cache. */
2130 if (fi
->base
->unwind
== fi
->unwind
)
2131 cache
= &fi
->prologue_cache
;
2133 cache
= &fi
->base_cache
;
2134 return fi
->base
->this_locals (fi
->next
, cache
);
2138 get_frame_args_address (struct frame_info
*fi
)
2141 if (get_frame_type (fi
) != NORMAL_FRAME
)
2143 /* If there isn't a frame address method, find it. */
2144 if (fi
->base
== NULL
)
2145 fi
->base
= frame_base_find_by_frame (fi
->next
);
2146 /* Sneaky: If the low-level unwind and high-level base code share a
2147 common unwinder, let them share the prologue cache. */
2148 if (fi
->base
->unwind
== fi
->unwind
)
2149 cache
= &fi
->prologue_cache
;
2151 cache
= &fi
->base_cache
;
2152 return fi
->base
->this_args (fi
->next
, cache
);
2155 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
2156 or -1 for a NULL frame. */
2159 frame_relative_level (struct frame_info
*fi
)
2168 get_frame_type (struct frame_info
*frame
)
2170 /* Some targets still don't use [generic] dummy frames. Catch them
2172 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
2173 && deprecated_frame_in_dummy (frame
))
2176 /* Some legacy code, e.g, mips_init_extra_frame_info() wants
2177 to determine the frame's type prior to it being completely
2178 initialized. Don't attempt to lazily initialize ->unwind for
2179 legacy code. It will be initialized in legacy_get_prev_frame(). */
2180 if (frame
->unwind
== NULL
&& !legacy_frame_p (current_gdbarch
))
2182 /* Initialize the frame's unwinder because it is that which
2183 provides the frame's type. */
2184 frame
->unwind
= frame_unwind_find_by_frame (frame
->next
);
2185 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
2186 type in the frame, the unwinder's type should be returned
2187 directly. Unfortunatly, legacy code, called by
2188 legacy_get_prev_frame, explicitly set the frames type using
2189 the method deprecated_set_frame_type(). */
2190 gdb_assert (frame
->unwind
->type
!= UNKNOWN_FRAME
);
2191 frame
->type
= frame
->unwind
->type
;
2193 if (frame
->type
== UNKNOWN_FRAME
)
2194 return NORMAL_FRAME
;
2200 deprecated_set_frame_type (struct frame_info
*frame
, enum frame_type type
)
2202 /* Arrrg! See comment in "frame.h". */
2206 struct frame_extra_info
*
2207 get_frame_extra_info (struct frame_info
*fi
)
2209 return fi
->extra_info
;
2212 struct frame_extra_info
*
2213 frame_extra_info_zalloc (struct frame_info
*fi
, long size
)
2215 fi
->extra_info
= frame_obstack_zalloc (size
);
2216 return fi
->extra_info
;
2220 deprecated_update_frame_pc_hack (struct frame_info
*frame
, CORE_ADDR pc
)
2223 fprintf_unfiltered (gdb_stdlog
,
2224 "{ deprecated_update_frame_pc_hack (frame=%d,pc=0x%s) }\n",
2225 frame
->level
, paddr_nz (pc
));
2226 /* NOTE: cagney/2003-03-11: Some architectures (e.g., Arm) are
2227 maintaining a locally allocated frame object. Since such frame's
2228 are not in the frame chain, it isn't possible to assume that the
2229 frame has a next. Sigh. */
2230 if (frame
->next
!= NULL
)
2232 /* While we're at it, update this frame's cached PC value, found
2233 in the next frame. Oh for the day when "struct frame_info"
2234 is opaque and this hack on hack can just go away. */
2235 frame
->next
->prev_pc
.value
= pc
;
2236 frame
->next
->prev_pc
.p
= 1;
2241 deprecated_update_frame_base_hack (struct frame_info
*frame
, CORE_ADDR base
)
2244 fprintf_unfiltered (gdb_stdlog
,
2245 "{ deprecated_update_frame_base_hack (frame=%d,base=0x%s) }\n",
2246 frame
->level
, paddr_nz (base
));
2247 /* See comment in "frame.h". */
2248 frame
->this_id
.value
.stack_addr
= base
;
2252 deprecated_set_frame_saved_regs_hack (struct frame_info
*frame
,
2253 CORE_ADDR
*saved_regs
)
2255 frame
->saved_regs
= saved_regs
;
2259 deprecated_set_frame_extra_info_hack (struct frame_info
*frame
,
2260 struct frame_extra_info
*extra_info
)
2262 frame
->extra_info
= extra_info
;
2266 deprecated_set_frame_next_hack (struct frame_info
*fi
,
2267 struct frame_info
*next
)
2273 deprecated_set_frame_prev_hack (struct frame_info
*fi
,
2274 struct frame_info
*prev
)
2280 deprecated_get_frame_context (struct frame_info
*fi
)
2286 deprecated_set_frame_context (struct frame_info
*fi
,
2287 struct context
*context
)
2289 fi
->context
= context
;
2293 deprecated_frame_xmalloc (void)
2295 struct frame_info
*frame
= XMALLOC (struct frame_info
);
2296 memset (frame
, 0, sizeof (*frame
));
2297 frame
->this_id
.p
= 1;
2302 deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs
,
2303 long sizeof_extra_info
)
2305 struct frame_info
*frame
= deprecated_frame_xmalloc ();
2306 make_cleanup (xfree
, frame
);
2307 if (sizeof_saved_regs
> 0)
2309 frame
->saved_regs
= xcalloc (1, sizeof_saved_regs
);
2310 make_cleanup (xfree
, frame
->saved_regs
);
2312 if (sizeof_extra_info
> 0)
2314 frame
->extra_info
= xcalloc (1, sizeof_extra_info
);
2315 make_cleanup (xfree
, frame
->extra_info
);
2320 /* Memory access methods. */
2323 get_frame_memory (struct frame_info
*this_frame
, CORE_ADDR addr
, void *buf
,
2326 read_memory (addr
, buf
, len
);
2330 get_frame_memory_signed (struct frame_info
*this_frame
, CORE_ADDR addr
,
2333 return read_memory_integer (addr
, len
);
2337 get_frame_memory_unsigned (struct frame_info
*this_frame
, CORE_ADDR addr
,
2340 return read_memory_unsigned_integer (addr
, len
);
2343 /* Architecture method. */
2346 get_frame_arch (struct frame_info
*this_frame
)
2348 return current_gdbarch
;
2351 /* Stack pointer methods. */
2354 get_frame_sp (struct frame_info
*this_frame
)
2356 return frame_sp_unwind (this_frame
->next
);
2360 frame_sp_unwind (struct frame_info
*next_frame
)
2362 /* Normality, an architecture that provides a way of obtaining any
2363 frame inner-most address. */
2364 if (gdbarch_unwind_sp_p (current_gdbarch
))
2365 return gdbarch_unwind_sp (current_gdbarch
, next_frame
);
2366 /* Things are looking grim. If it's the inner-most frame and there
2367 is a TARGET_READ_SP then that can be used. */
2368 if (next_frame
->level
< 0 && TARGET_READ_SP_P ())
2369 return TARGET_READ_SP ();
2370 /* Now things are really are grim. Hope that the value returned by
2371 the SP_REGNUM register is meaningful. */
2375 frame_unwind_unsigned_register (next_frame
, SP_REGNUM
, &sp
);
2378 internal_error (__FILE__
, __LINE__
, "Missing unwind SP method");
2383 legacy_frame_p (struct gdbarch
*current_gdbarch
)
2385 return (DEPRECATED_INIT_FRAME_PC_P ()
2386 || DEPRECATED_INIT_FRAME_PC_FIRST_P ()
2387 || DEPRECATED_INIT_EXTRA_FRAME_INFO_P ()
2388 || DEPRECATED_FRAME_CHAIN_P ()
2389 || !gdbarch_unwind_dummy_id_p (current_gdbarch
));
2392 extern initialize_file_ftype _initialize_frame
; /* -Wmissing-prototypes */
2394 static struct cmd_list_element
*set_backtrace_cmdlist
;
2395 static struct cmd_list_element
*show_backtrace_cmdlist
;
2398 set_backtrace_cmd (char *args
, int from_tty
)
2400 help_list (set_backtrace_cmdlist
, "set backtrace ", -1, gdb_stdout
);
2404 show_backtrace_cmd (char *args
, int from_tty
)
2406 cmd_show_list (show_backtrace_cmdlist
, from_tty
, "");
2410 _initialize_frame (void)
2412 obstack_init (&frame_cache_obstack
);
2414 add_prefix_cmd ("backtrace", class_maintenance
, set_backtrace_cmd
, "\
2415 Set backtrace specific variables.\n\
2416 Configure backtrace variables such as the backtrace limit",
2417 &set_backtrace_cmdlist
, "set backtrace ",
2418 0/*allow-unknown*/, &setlist
);
2419 add_prefix_cmd ("backtrace", class_maintenance
, show_backtrace_cmd
, "\
2420 Show backtrace specific variables\n\
2421 Show backtrace variables such as the backtrace limit",
2422 &show_backtrace_cmdlist
, "show backtrace ",
2423 0/*allow-unknown*/, &showlist
);
2425 add_setshow_boolean_cmd ("past-main", class_obscure
,
2426 &backtrace_past_main
, "\
2427 Set whether backtraces should continue past \"main\".\n\
2428 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2429 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2430 of the stack trace.", "\
2431 Show whether backtraces should continue past \"main\".\n\
2432 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2433 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2434 of the stack trace.",
2435 NULL
, NULL
, &set_backtrace_cmdlist
,
2436 &show_backtrace_cmdlist
);
2438 add_setshow_uinteger_cmd ("limit", class_obscure
,
2439 &backtrace_limit
, "\
2440 Set an upper bound on the number of backtrace levels.\n\
2441 No more than the specified number of frames can be displayed or examined.\n\
2442 Zero is unlimited.", "\
2443 Show the upper bound on the number of backtrace levels.",
2444 NULL
, NULL
, &set_backtrace_cmdlist
,
2445 &show_backtrace_cmdlist
);
2447 /* Debug this files internals. */
2448 add_show_from_set (add_set_cmd ("frame", class_maintenance
, var_zinteger
,
2449 &frame_debug
, "Set frame debugging.\n\
2450 When non-zero, frame specific internal debugging is enabled.", &setdebuglist
),