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
, DEPRECATED_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
, DEPRECATED_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
, DEPRECATED_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
, DEPRECATED_REGISTER_VIRTUAL_SIZE (regnum
));
674 put_frame_register (struct frame_info
*frame
, int regnum
, const void *buf
)
676 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
681 frame_register (frame
, regnum
, &optim
, &lval
, &addr
, &realnum
, NULL
);
683 error ("Attempt to assign to a value that was optimized out.");
688 /* FIXME: write_memory doesn't yet take constant buffers.
690 char tmp
[MAX_REGISTER_SIZE
];
691 memcpy (tmp
, buf
, register_size (gdbarch
, regnum
));
692 write_memory (addr
, tmp
, register_size (gdbarch
, regnum
));
696 regcache_cooked_write (current_regcache
, realnum
, buf
);
699 error ("Attempt to assign to an unmodifiable value.");
703 /* frame_register_read ()
705 Find and return the value of REGNUM for the specified stack frame.
706 The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
708 Returns 0 if the register value could not be found. */
711 frame_register_read (struct frame_info
*frame
, int regnum
, void *myaddr
)
717 frame_register (frame
, regnum
, &optimized
, &lval
, &addr
, &realnum
, myaddr
);
719 /* FIXME: cagney/2002-05-15: This test, is just bogus.
721 It indicates that the target failed to supply a value for a
722 register because it was "not available" at this time. Problem
723 is, the target still has the register and so get saved_register()
724 may be returning a value saved on the stack. */
726 if (register_cached (regnum
) < 0)
727 return 0; /* register value not available */
733 /* Map between a frame register number and its name. A frame register
734 space is a superset of the cooked register space --- it also
735 includes builtin registers. */
738 frame_map_name_to_regnum (struct frame_info
*frame
, const char *name
, int len
)
740 return user_reg_map_name_to_regnum (get_frame_arch (frame
), name
, len
);
744 frame_map_regnum_to_name (struct frame_info
*frame
, int regnum
)
746 return user_reg_map_regnum_to_name (get_frame_arch (frame
), regnum
);
749 /* Create a sentinel frame. */
751 static struct frame_info
*
752 create_sentinel_frame (struct regcache
*regcache
)
754 struct frame_info
*frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
755 frame
->type
= NORMAL_FRAME
;
757 /* Explicitly initialize the sentinel frame's cache. Provide it
758 with the underlying regcache. In the future additional
759 information, such as the frame's thread will be added. */
760 frame
->prologue_cache
= sentinel_frame_cache (regcache
);
761 /* For the moment there is only one sentinel frame implementation. */
762 frame
->unwind
= sentinel_frame_unwind
;
763 /* Link this frame back to itself. The frame is self referential
764 (the unwound PC is the same as the pc), so make it so. */
766 /* Make the sentinel frame's ID valid, but invalid. That way all
767 comparisons with it should fail. */
768 frame
->this_id
.p
= 1;
769 frame
->this_id
.value
= null_frame_id
;
772 fprintf_unfiltered (gdb_stdlog
, "{ create_sentinel_frame (...) -> ");
773 fprint_frame (gdb_stdlog
, frame
);
774 fprintf_unfiltered (gdb_stdlog
, " }\n");
779 /* Info about the innermost stack frame (contents of FP register) */
781 static struct frame_info
*current_frame
;
783 /* Cache for frame addresses already read by gdb. Valid only while
784 inferior is stopped. Control variables for the frame cache should
785 be local to this module. */
787 static struct obstack frame_cache_obstack
;
790 frame_obstack_zalloc (unsigned long size
)
792 void *data
= obstack_alloc (&frame_cache_obstack
, size
);
793 memset (data
, 0, size
);
798 frame_saved_regs_zalloc (struct frame_info
*fi
)
800 fi
->saved_regs
= (CORE_ADDR
*)
801 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
802 return fi
->saved_regs
;
806 deprecated_get_frame_saved_regs (struct frame_info
*fi
)
808 return fi
->saved_regs
;
811 /* Return the innermost (currently executing) stack frame. This is
812 split into two functions. The function unwind_to_current_frame()
813 is wrapped in catch exceptions so that, even when the unwind of the
814 sentinel frame fails, the function still returns a stack frame. */
817 unwind_to_current_frame (struct ui_out
*ui_out
, void *args
)
819 struct frame_info
*frame
= get_prev_frame (args
);
820 /* A sentinel frame can fail to unwind, eg, because it's PC value
821 lands in somewhere like start. */
824 current_frame
= frame
;
829 get_current_frame (void)
831 /* First check, and report, the lack of registers. Having GDB
832 report "No stack!" or "No memory" when the target doesn't even
833 have registers is very confusing. Besides, "printcmd.exp"
834 explicitly checks that ``print $pc'' with no registers prints "No
836 if (!target_has_registers
)
837 error ("No registers.");
838 if (!target_has_stack
)
840 if (!target_has_memory
)
841 error ("No memory.");
842 if (current_frame
== NULL
)
844 struct frame_info
*sentinel_frame
=
845 create_sentinel_frame (current_regcache
);
846 if (catch_exceptions (uiout
, unwind_to_current_frame
, sentinel_frame
,
847 NULL
, RETURN_MASK_ERROR
) != 0)
849 /* Oops! Fake a current frame? Is this useful? It has a PC
850 of zero, for instance. */
851 current_frame
= sentinel_frame
;
854 return current_frame
;
857 /* The "selected" stack frame is used by default for local and arg
858 access. May be zero, for no selected frame. */
860 struct frame_info
*deprecated_selected_frame
;
862 /* Return the selected frame. Always non-null (unless there isn't an
863 inferior sufficient for creating a frame) in which case an error is
867 get_selected_frame (void)
869 if (deprecated_selected_frame
== NULL
)
870 /* Hey! Don't trust this. It should really be re-finding the
871 last selected frame of the currently selected thread. This,
872 though, is better than nothing. */
873 select_frame (get_current_frame ());
874 /* There is always a frame. */
875 gdb_assert (deprecated_selected_frame
!= NULL
);
876 return deprecated_selected_frame
;
879 /* This is a variant of get_selected_frame which can be called when
880 the inferior does not have a frame; in that case it will return
881 NULL instead of calling error (). */
884 deprecated_safe_get_selected_frame (void)
886 if (!target_has_registers
|| !target_has_stack
|| !target_has_memory
)
888 return get_selected_frame ();
891 /* Select frame FI (or NULL - to invalidate the current frame). */
894 select_frame (struct frame_info
*fi
)
898 deprecated_selected_frame
= fi
;
899 /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
900 frame is being invalidated. */
901 if (selected_frame_level_changed_hook
)
902 selected_frame_level_changed_hook (frame_relative_level (fi
));
904 /* FIXME: kseitz/2002-08-28: It would be nice to call
905 selected_frame_level_changed_event right here, but due to limitations
906 in the current interfaces, we would end up flooding UIs with events
907 because select_frame is used extensively internally.
909 Once we have frame-parameterized frame (and frame-related) commands,
910 the event notification can be moved here, since this function will only
911 be called when the users selected frame is being changed. */
913 /* Ensure that symbols for this frame are read in. Also, determine the
914 source language of this frame, and switch to it if desired. */
917 s
= find_pc_symtab (get_frame_pc (fi
));
919 && s
->language
!= current_language
->la_language
920 && s
->language
!= language_unknown
921 && language_mode
== language_mode_auto
)
923 set_language (s
->language
);
928 /* Return the register saved in the simplistic ``saved_regs'' cache.
929 If the value isn't here AND a value is needed, try the next inner
933 legacy_saved_regs_prev_register (struct frame_info
*next_frame
,
934 void **this_prologue_cache
,
935 int regnum
, int *optimizedp
,
936 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
937 int *realnump
, void *bufferp
)
939 /* HACK: New code is passed the next frame and this cache.
940 Unfortunatly, old code expects this frame. Since this is a
941 backward compatibility hack, cheat by walking one level along the
942 prologue chain to the frame the old code expects.
944 Do not try this at home. Professional driver, closed course. */
945 struct frame_info
*frame
= next_frame
->prev
;
946 gdb_assert (frame
!= NULL
);
948 if (deprecated_get_frame_saved_regs (frame
) == NULL
)
950 /* If nothing's initialized the saved regs, do it now. */
951 gdb_assert (DEPRECATED_FRAME_INIT_SAVED_REGS_P ());
952 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
953 gdb_assert (deprecated_get_frame_saved_regs (frame
) != NULL
);
956 if (deprecated_get_frame_saved_regs (frame
) != NULL
957 && deprecated_get_frame_saved_regs (frame
)[regnum
] != 0)
959 if (regnum
== SP_REGNUM
)
961 /* SP register treated specially. */
967 /* NOTE: cagney/2003-05-09: In-lined store_address with
968 it's body - store_unsigned_integer. */
969 store_unsigned_integer (bufferp
, REGISTER_RAW_SIZE (regnum
),
970 deprecated_get_frame_saved_regs (frame
)[regnum
]);
974 /* Any other register is saved in memory, fetch it but cache
975 a local copy of its value. */
977 *lvalp
= lval_memory
;
978 *addrp
= deprecated_get_frame_saved_regs (frame
)[regnum
];
983 /* Save each register value, as it is read in, in a
984 frame based cache. */
985 void **regs
= (*this_prologue_cache
);
988 int sizeof_cache
= ((NUM_REGS
+ NUM_PSEUDO_REGS
)
990 regs
= frame_obstack_zalloc (sizeof_cache
);
991 (*this_prologue_cache
) = regs
;
993 if (regs
[regnum
] == NULL
)
996 = frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum
));
997 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], regs
[regnum
],
998 REGISTER_RAW_SIZE (regnum
));
1000 memcpy (bufferp
, regs
[regnum
], REGISTER_RAW_SIZE (regnum
));
1002 /* Read the value in from memory. */
1003 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], bufferp
,
1004 REGISTER_RAW_SIZE (regnum
));
1011 /* No luck. Assume this and the next frame have the same register
1012 value. Pass the unwind request down the frame chain to the next
1013 frame. Hopefully that frame will find the register's location. */
1014 frame_register_unwind (next_frame
, regnum
, optimizedp
, lvalp
, addrp
,
1019 legacy_saved_regs_this_id (struct frame_info
*next_frame
,
1020 void **this_prologue_cache
,
1021 struct frame_id
*id
)
1023 /* legacy_get_prev_frame() always sets ->this_id.p, hence this is
1025 internal_error (__FILE__
, __LINE__
, "legacy_saved_regs_this_id() called");
1028 const struct frame_unwind legacy_saved_regs_unwinder
= {
1029 /* Not really. It gets overridden by legacy_get_prev_frame. */
1031 legacy_saved_regs_this_id
,
1032 legacy_saved_regs_prev_register
1034 const struct frame_unwind
*legacy_saved_regs_unwind
= &legacy_saved_regs_unwinder
;
1037 /* Function: deprecated_generic_get_saved_register
1038 Find register number REGNUM relative to FRAME and put its (raw,
1039 target format) contents in *RAW_BUFFER.
1041 Set *OPTIMIZED if the variable was optimized out (and thus can't be
1042 fetched). Note that this is never set to anything other than zero
1043 in this implementation.
1045 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
1046 whether the value was fetched from memory, from a register, or in a
1047 strange and non-modifiable way (e.g. a frame pointer which was
1048 calculated rather than fetched). We will use not_lval for values
1049 fetched from generic dummy frames.
1051 Set *ADDRP to the address, either in memory or as a
1052 DEPRECATED_REGISTER_BYTE offset into the registers array. If the
1053 value is stored in a dummy frame, set *ADDRP to zero.
1055 The argument RAW_BUFFER must point to aligned memory. */
1058 deprecated_generic_get_saved_register (char *raw_buffer
, int *optimized
,
1060 struct frame_info
*frame
, int regnum
,
1061 enum lval_type
*lval
)
1063 if (!target_has_registers
)
1064 error ("No registers.");
1066 /* Normal systems don't optimize out things with register numbers. */
1067 if (optimized
!= NULL
)
1070 if (addrp
) /* default assumption: not found in memory */
1073 /* Note: since the current frame's registers could only have been
1074 saved by frames INTERIOR TO the current frame, we skip examining
1075 the current frame itself: otherwise, we would be getting the
1076 previous frame's registers which were saved by the current frame. */
1080 for (frame
= get_next_frame (frame
);
1081 frame_relative_level (frame
) >= 0;
1082 frame
= get_next_frame (frame
))
1084 if (get_frame_type (frame
) == DUMMY_FRAME
)
1086 if (lval
) /* found it in a CALL_DUMMY frame */
1089 /* FIXME: cagney/2002-06-26: This should be via the
1090 gdbarch_register_read() method so that it, on the
1091 fly, constructs either a raw or pseudo register
1092 from the raw register cache. */
1094 (deprecated_find_dummy_frame_regcache (get_frame_pc (frame
),
1095 get_frame_base (frame
)),
1096 regnum
, raw_buffer
);
1100 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
1101 if (deprecated_get_frame_saved_regs (frame
) != NULL
1102 && deprecated_get_frame_saved_regs (frame
)[regnum
] != 0)
1104 if (lval
) /* found it saved on the stack */
1105 *lval
= lval_memory
;
1106 if (regnum
== SP_REGNUM
)
1108 if (raw_buffer
) /* SP register treated specially */
1109 /* NOTE: cagney/2003-05-09: In-line store_address
1110 with it's body - store_unsigned_integer. */
1111 store_unsigned_integer (raw_buffer
,
1112 REGISTER_RAW_SIZE (regnum
),
1113 deprecated_get_frame_saved_regs (frame
)[regnum
]);
1117 if (addrp
) /* any other register */
1118 *addrp
= deprecated_get_frame_saved_regs (frame
)[regnum
];
1120 read_memory (deprecated_get_frame_saved_regs (frame
)[regnum
], raw_buffer
,
1121 REGISTER_RAW_SIZE (regnum
));
1128 /* If we get thru the loop to this point, it means the register was
1129 not saved in any frame. Return the actual live-register value. */
1131 if (lval
) /* found it in a live register */
1132 *lval
= lval_register
;
1134 *addrp
= DEPRECATED_REGISTER_BYTE (regnum
);
1136 deprecated_read_register_gen (regnum
, raw_buffer
);
1139 /* Determine the frame's type based on its PC. */
1141 static enum frame_type
1142 frame_type_from_pc (CORE_ADDR pc
)
1144 /* FIXME: cagney/2002-11-24: Can't yet directly call
1145 pc_in_dummy_frame() as some architectures don't set
1146 PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the
1147 latter is implemented by simply calling pc_in_dummy_frame). */
1148 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1149 && DEPRECATED_PC_IN_CALL_DUMMY (pc
, 0, 0))
1154 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
1155 if (PC_IN_SIGTRAMP (pc
, name
))
1156 return SIGTRAMP_FRAME
;
1158 return NORMAL_FRAME
;
1162 /* Create an arbitrary (i.e. address specified by user) or innermost frame.
1163 Always returns a non-NULL value. */
1166 create_new_frame (CORE_ADDR addr
, CORE_ADDR pc
)
1168 struct frame_info
*fi
;
1172 fprintf_unfiltered (gdb_stdlog
,
1173 "{ create_new_frame (addr=0x%s, pc=0x%s) ",
1174 paddr_nz (addr
), paddr_nz (pc
));
1177 fi
= frame_obstack_zalloc (sizeof (struct frame_info
));
1179 fi
->next
= create_sentinel_frame (current_regcache
);
1181 /* Select/initialize both the unwind function and the frame's type
1183 fi
->unwind
= frame_unwind_find_by_frame (fi
->next
);
1184 if (fi
->unwind
->type
!= UNKNOWN_FRAME
)
1185 fi
->type
= fi
->unwind
->type
;
1187 fi
->type
= frame_type_from_pc (pc
);
1190 deprecated_update_frame_base_hack (fi
, addr
);
1191 deprecated_update_frame_pc_hack (fi
, pc
);
1193 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1194 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, fi
);
1198 fprintf_unfiltered (gdb_stdlog
, "-> ");
1199 fprint_frame (gdb_stdlog
, fi
);
1200 fprintf_unfiltered (gdb_stdlog
, " }\n");
1206 /* Return the frame that THIS_FRAME calls (NULL if THIS_FRAME is the
1207 innermost frame). Be careful to not fall off the bottom of the
1208 frame chain and onto the sentinel frame. */
1211 get_next_frame (struct frame_info
*this_frame
)
1213 if (this_frame
->level
> 0)
1214 return this_frame
->next
;
1220 deprecated_get_next_frame_hack (struct frame_info
*this_frame
)
1222 return this_frame
->next
;
1225 /* Flush the entire frame cache. */
1228 flush_cached_frames (void)
1230 /* Since we can't really be sure what the first object allocated was */
1231 obstack_free (&frame_cache_obstack
, 0);
1232 obstack_init (&frame_cache_obstack
);
1234 current_frame
= NULL
; /* Invalidate cache */
1235 select_frame (NULL
);
1236 annotate_frames_invalid ();
1238 fprintf_unfiltered (gdb_stdlog
, "{ flush_cached_frames () }\n");
1241 /* Flush the frame cache, and start a new one if necessary. */
1244 reinit_frame_cache (void)
1246 flush_cached_frames ();
1248 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
1249 if (PIDGET (inferior_ptid
) != 0)
1251 select_frame (get_current_frame ());
1255 /* Create the previous frame using the deprecated methods
1256 INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */
1258 static struct frame_info
*
1259 legacy_get_prev_frame (struct frame_info
*this_frame
)
1261 CORE_ADDR address
= 0;
1262 struct frame_info
*prev
;
1265 /* Don't frame_debug print legacy_get_prev_frame() here, just
1266 confuses the output. */
1268 /* Allocate the new frame.
1270 There is no reason to worry about memory leaks, should the
1271 remainder of the function fail. The allocated memory will be
1272 quickly reclaimed when the frame cache is flushed, and the `we've
1273 been here before' check, in get_prev_frame will stop repeated
1274 memory allocation calls. */
1275 prev
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
1276 prev
->level
= this_frame
->level
+ 1;
1278 /* Do not completly wire it in to the frame chain. Some (bad) code
1279 in INIT_FRAME_EXTRA_INFO tries to look along frame->prev to pull
1280 some fancy tricks (of course such code is, by definition,
1283 On the other hand, methods, such as get_frame_pc() and
1284 get_frame_base() rely on being able to walk along the frame
1285 chain. Make certain that at least they work by providing that
1286 link. Of course things manipulating prev can't go back. */
1287 prev
->next
= this_frame
;
1289 /* NOTE: cagney/2002-11-18: Should have been correctly setting the
1290 frame's type here, before anything else, and not last, at the
1291 bottom of this function. The various
1292 DEPRECATED_INIT_EXTRA_FRAME_INFO, DEPRECATED_INIT_FRAME_PC,
1293 DEPRECATED_INIT_FRAME_PC_FIRST and
1294 DEPRECATED_FRAME_INIT_SAVED_REGS methods are full of work-arounds
1295 that handle the frame not being correctly set from the start.
1296 Unfortunatly those same work-arounds rely on the type defaulting
1297 to NORMAL_FRAME. Ulgh! The new frame code does not have this
1299 prev
->type
= UNKNOWN_FRAME
;
1301 /* A legacy frame's ID is always computed here. Mark it as valid. */
1302 prev
->this_id
.p
= 1;
1304 /* Handle sentinel frame unwind as a special case. */
1305 if (this_frame
->level
< 0)
1307 /* Try to unwind the PC. If that doesn't work, assume we've reached
1308 the oldest frame and simply return. Is there a better sentinal
1309 value? The unwound PC value is then used to initialize the new
1310 previous frame's type.
1312 Note that the pc-unwind is intentionally performed before the
1313 frame chain. This is ok since, for old targets, both
1314 frame_pc_unwind (nee, DEPRECATED_FRAME_SAVED_PC) and
1315 DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
1316 have already been initialized (using
1317 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1320 By unwinding the PC first, it becomes possible to, in the case of
1321 a dummy frame, avoid also unwinding the frame ID. This is
1322 because (well ignoring the PPC) a dummy frame can be located
1323 using THIS_FRAME's frame ID. */
1325 deprecated_update_frame_pc_hack (prev
, frame_pc_unwind (this_frame
));
1326 if (get_frame_pc (prev
) == 0)
1328 /* The allocated PREV_FRAME will be reclaimed when the frame
1329 obstack is next purged. */
1332 fprintf_unfiltered (gdb_stdlog
, "-> ");
1333 fprint_frame (gdb_stdlog
, NULL
);
1334 fprintf_unfiltered (gdb_stdlog
,
1335 " // unwound legacy PC zero }\n");
1340 /* Set the unwind functions based on that identified PC. Ditto
1341 for the "type" but strongly prefer the unwinder's frame type. */
1342 prev
->unwind
= frame_unwind_find_by_frame (prev
->next
);
1343 if (prev
->unwind
->type
== UNKNOWN_FRAME
)
1344 prev
->type
= frame_type_from_pc (get_frame_pc (prev
));
1346 prev
->type
= prev
->unwind
->type
;
1348 /* Find the prev's frame's ID. */
1349 if (prev
->type
== DUMMY_FRAME
1350 && gdbarch_unwind_dummy_id_p (current_gdbarch
))
1352 /* When unwinding a normal frame, the stack structure is
1353 determined by analyzing the frame's function's code (be
1354 it using brute force prologue analysis, or the dwarf2
1355 CFI). In the case of a dummy frame, that simply isn't
1356 possible. The The PC is either the program entry point,
1357 or some random address on the stack. Trying to use that
1358 PC to apply standard frame ID unwind techniques is just
1359 asking for trouble. */
1360 /* Use an architecture specific method to extract the prev's
1361 dummy ID from the next frame. Note that this method uses
1362 frame_register_unwind to obtain the register values
1363 needed to determine the dummy frame's ID. */
1364 prev
->this_id
.value
= gdbarch_unwind_dummy_id (current_gdbarch
,
1369 /* We're unwinding a sentinel frame, the PC of which is
1370 pointing at a stack dummy. Fake up the dummy frame's ID
1371 using the same sequence as is found a traditional
1372 unwinder. Once all architectures supply the
1373 unwind_dummy_id method, this code can go away. */
1374 prev
->this_id
.value
= frame_id_build (deprecated_read_fp (),
1378 /* Check that the unwound ID is valid. */
1379 if (!frame_id_p (prev
->this_id
.value
))
1383 fprintf_unfiltered (gdb_stdlog
, "-> ");
1384 fprint_frame (gdb_stdlog
, NULL
);
1385 fprintf_unfiltered (gdb_stdlog
,
1386 " // unwound legacy ID invalid }\n");
1391 /* Check that the new frame isn't inner to (younger, below,
1392 next) the old frame. If that happens the frame unwind is
1394 /* FIXME: cagney/2003-02-25: Ignore the sentinel frame since
1395 that doesn't have a valid frame ID. Should instead set the
1396 sentinel frame's frame ID to a `sentinel'. Leave it until
1397 after the switch to storing the frame ID, instead of the
1398 frame base, in the frame object. */
1401 this_frame
->prev
= prev
;
1403 /* FIXME: cagney/2002-01-19: This call will go away. Instead of
1404 initializing extra info, all frames will use the frame_cache
1405 (passed to the unwind functions) to store additional frame
1406 info. Unfortunatly legacy targets can't use
1407 legacy_get_prev_frame() to unwind the sentinel frame and,
1408 consequently, are forced to take this code path and rely on
1409 the below call to DEPRECATED_INIT_EXTRA_FRAME_INFO to
1410 initialize the inner-most frame. */
1411 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1413 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, prev
);
1416 if (prev
->type
== NORMAL_FRAME
)
1417 prev
->this_id
.value
.code_addr
1418 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1422 fprintf_unfiltered (gdb_stdlog
, "-> ");
1423 fprint_frame (gdb_stdlog
, prev
);
1424 fprintf_unfiltered (gdb_stdlog
, " } // legacy innermost frame\n");
1429 /* This code only works on normal frames. A sentinel frame, where
1430 the level is -1, should never reach this code. */
1431 gdb_assert (this_frame
->level
>= 0);
1433 /* On some machines it is possible to call a function without
1434 setting up a stack frame for it. On these machines, we
1435 define this macro to take two args; a frameinfo pointer
1436 identifying a frame and a variable to set or clear if it is
1437 or isn't leafless. */
1439 /* Still don't want to worry about this except on the innermost
1440 frame. This macro will set FROMLEAF if THIS_FRAME is a frameless
1441 function invocation. */
1442 if (this_frame
->level
== 0)
1443 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
1444 the frame chain, not just the inner most frame! The generic,
1445 per-architecture, frame code should handle this and the below
1446 should simply be removed. */
1447 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (this_frame
);
1452 /* A frameless inner-most frame. The `FP' (which isn't an
1453 architecture frame-pointer register!) of the caller is the same
1455 /* FIXME: 2002-11-09: There isn't any reason to special case this
1456 edge condition. Instead the per-architecture code should hande
1458 /* FIXME: cagney/2003-06-16: This returns the inner most stack
1459 address for the previous frame, that, however, is wrong. It
1460 should be the inner most stack address for the previous to
1461 previous frame. This is because it is the previous to previous
1462 frame's innermost stack address that is constant through out
1463 the lifetime of the previous frame (trust me :-). */
1464 address
= get_frame_base (this_frame
);
1467 /* Two macros defined in tm.h specify the machine-dependent
1468 actions to be performed here.
1470 First, get the frame's chain-pointer.
1472 If that is zero, the frame is the outermost frame or a leaf
1473 called by the outermost frame. This means that if start
1474 calls main without a frame, we'll return 0 (which is fine
1477 Nope; there's a problem. This also returns when the current
1478 routine is a leaf of main. This is unacceptable. We move
1479 this to after the ffi test; I'd rather have backtraces from
1480 start go curfluy than have an abort called from main not show
1482 if (DEPRECATED_FRAME_CHAIN_P ())
1483 address
= DEPRECATED_FRAME_CHAIN (this_frame
);
1486 /* Someone is part way through coverting an old architecture
1487 to the new frame code. Implement FRAME_CHAIN the way the
1489 /* Find PREV frame's unwinder. */
1490 prev
->unwind
= frame_unwind_find_by_frame (this_frame
->next
);
1491 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
1492 type in the frame, the unwinder's type should be returned
1493 directly. Unfortunatly, legacy code, called by
1494 legacy_get_prev_frame, explicitly set the frames type
1495 using the method deprecated_set_frame_type(). */
1496 prev
->type
= prev
->unwind
->type
;
1497 /* Find PREV frame's ID. */
1498 prev
->unwind
->this_id (this_frame
,
1499 &prev
->prologue_cache
,
1500 &prev
->this_id
.value
);
1501 prev
->this_id
.p
= 1;
1502 address
= prev
->this_id
.value
.stack_addr
;
1505 if (!legacy_frame_chain_valid (address
, this_frame
))
1509 fprintf_unfiltered (gdb_stdlog
, "-> ");
1510 fprint_frame (gdb_stdlog
, NULL
);
1511 fprintf_unfiltered (gdb_stdlog
,
1512 " // legacy frame chain invalid }\n");
1521 fprintf_unfiltered (gdb_stdlog
, "-> ");
1522 fprint_frame (gdb_stdlog
, NULL
);
1523 fprintf_unfiltered (gdb_stdlog
,
1524 " // legacy frame chain NULL }\n");
1529 /* Link in the already allocated prev frame. */
1530 this_frame
->prev
= prev
;
1531 deprecated_update_frame_base_hack (prev
, address
);
1533 /* This change should not be needed, FIXME! We should determine
1534 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1535 after DEPRECATED_INIT_EXTRA_FRAME_INFO and come up with a simple
1536 way to express what goes on here.
1538 DEPRECATED_INIT_EXTRA_FRAME_INFO is called from two places:
1539 create_new_frame (where the PC is already set up) and here (where
1540 it isn't). DEPRECATED_INIT_FRAME_PC is only called from here,
1541 always after DEPRECATED_INIT_EXTRA_FRAME_INFO.
1543 The catch is the MIPS, where DEPRECATED_INIT_EXTRA_FRAME_INFO
1544 requires the PC value (which hasn't been set yet). Some other
1545 machines appear to require DEPRECATED_INIT_EXTRA_FRAME_INFO
1546 before they can do DEPRECATED_INIT_FRAME_PC. Phoo.
1548 We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
1549 complication to an already overcomplicated part of GDB.
1550 gnu@cygnus.com, 15Sep92.
1552 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
1553 DEPRECATED_INIT_EXTRA_FRAME_INFO, one possible scheme:
1555 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1556 (deprecated_read_fp ()), read_pc ()). Machines with extra frame
1557 info would do that (or the local equivalent) and then set the
1560 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1561 create_new_frame would no longer init extra frame info;
1562 SETUP_ARBITRARY_FRAME would have to do that.
1564 INIT_PREV_FRAME(fromleaf, prev) Replace
1565 DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC.
1566 This should also return a flag saying whether to keep the new
1567 frame, or whether to discard it, because on some machines (e.g.
1568 mips) it is really awkward to have DEPRECATED_FRAME_CHAIN_VALID
1569 called BEFORE DEPRECATED_INIT_EXTRA_FRAME_INFO (there is no good
1570 way to get information deduced in DEPRECATED_FRAME_CHAIN_VALID
1571 into the extra fields of the new frame). std_frame_pc(fromleaf,
1574 This is the default setting for INIT_PREV_FRAME. It just does
1575 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1576 will call it from INIT_PREV_FRAME (either at the beginning, the
1577 end, or in the middle). Some machines won't use it.
1579 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1581 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1582 reason for things to be this complicated.
1584 The trick is to assume that there is always a frame. Instead of
1585 special casing the inner-most frame, create fake frame
1586 (containing the hardware registers) that is inner to the
1587 user-visible inner-most frame (...) and then unwind from that.
1588 That way architecture code can use use the standard
1589 frame_XX_unwind() functions and not differentiate between the
1590 inner most and any other case.
1592 Since there is always a frame to unwind from, there is always
1593 somewhere (THIS_FRAME) to store all the info needed to construct
1594 a new (previous) frame without having to first create it. This
1595 means that the convolution below - needing to carefully order a
1596 frame's initialization - isn't needed.
1598 The irony here though, is that DEPRECATED_FRAME_CHAIN(), at least
1599 for a more up-to-date architecture, always calls
1600 FRAME_SAVED_PC(), and FRAME_SAVED_PC() computes the PC but
1601 without first needing the frame! Instead of the convolution
1602 below, we could have simply called FRAME_SAVED_PC() and been done
1603 with it! Note that FRAME_SAVED_PC() is being superseed by
1604 frame_pc_unwind() and that function does have somewhere to cache
1607 if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
1608 deprecated_update_frame_pc_hack (prev
,
1609 DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf
,
1612 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1613 DEPRECATED_INIT_EXTRA_FRAME_INFO (fromleaf
, prev
);
1615 /* This entry is in the frame queue now, which is good since
1616 FRAME_SAVED_PC may use that queue to figure out its value (see
1617 tm-sparc.h). We want the pc saved in the inferior frame. */
1618 if (DEPRECATED_INIT_FRAME_PC_P ())
1619 deprecated_update_frame_pc_hack (prev
,
1620 DEPRECATED_INIT_FRAME_PC (fromleaf
,
1623 /* If ->frame and ->pc are unchanged, we are in the process of
1624 getting ourselves into an infinite backtrace. Some architectures
1625 check this in DEPRECATED_FRAME_CHAIN or thereabouts, but it seems
1626 like there is no reason this can't be an architecture-independent
1628 if (get_frame_base (prev
) == get_frame_base (this_frame
)
1629 && get_frame_pc (prev
) == get_frame_pc (this_frame
))
1631 this_frame
->prev
= NULL
;
1632 obstack_free (&frame_cache_obstack
, prev
);
1635 fprintf_unfiltered (gdb_stdlog
, "-> ");
1636 fprint_frame (gdb_stdlog
, NULL
);
1637 fprintf_unfiltered (gdb_stdlog
,
1638 " // legacy this.id == prev.id }\n");
1643 /* Initialize the code used to unwind the frame PREV based on the PC
1644 (and probably other architectural information). The PC lets you
1645 check things like the debug info at that point (dwarf2cfi?) and
1646 use that to decide how the frame should be unwound.
1648 If there isn't a FRAME_CHAIN, the code above will have already
1650 if (prev
->unwind
== NULL
)
1651 prev
->unwind
= frame_unwind_find_by_frame (prev
->next
);
1653 /* If the unwinder provides a frame type, use it. Otherwize
1654 continue on to that heuristic mess. */
1655 if (prev
->unwind
->type
!= UNKNOWN_FRAME
)
1657 prev
->type
= prev
->unwind
->type
;
1658 if (prev
->type
== NORMAL_FRAME
)
1659 /* FIXME: cagney/2003-06-16: would get_frame_pc() be better? */
1660 prev
->this_id
.value
.code_addr
1661 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1664 fprintf_unfiltered (gdb_stdlog
, "-> ");
1665 fprint_frame (gdb_stdlog
, prev
);
1666 fprintf_unfiltered (gdb_stdlog
, " } // legacy with unwound type\n");
1671 /* NOTE: cagney/2002-11-18: The code segments, found in
1672 create_new_frame and get_prev_frame(), that initializes the
1673 frames type is subtly different. The latter only updates ->type
1674 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1675 get_prev_frame() overriding the frame's type when the INIT code
1676 has previously set it. This is really somewhat bogus. The
1677 initialization, as seen in create_new_frame(), should occur
1678 before the INIT function has been called. */
1679 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1680 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
1681 ? DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (prev
), 0, 0)
1682 : pc_in_dummy_frame (get_frame_pc (prev
))))
1683 prev
->type
= DUMMY_FRAME
;
1686 /* FIXME: cagney/2002-11-10: This should be moved to before the
1687 INIT code above so that the INIT code knows what the frame's
1688 type is (in fact, for a [generic] dummy-frame, the type can
1689 be set and then the entire initialization can be skipped.
1690 Unforunatly, its the INIT code that sets the PC (Hmm, catch
1693 find_pc_partial_function (get_frame_pc (prev
), &name
, NULL
, NULL
);
1694 if (PC_IN_SIGTRAMP (get_frame_pc (prev
), name
))
1695 prev
->type
= SIGTRAMP_FRAME
;
1696 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1697 architectures are forcing the frame's type in INIT so we
1698 don't want to override it here. Remember, NORMAL_FRAME == 0,
1699 so it all works (just :-/). Once this initialization is
1700 moved to the start of this function, all this nastness will
1704 if (prev
->type
== NORMAL_FRAME
)
1705 prev
->this_id
.value
.code_addr
1706 = get_pc_function_start (prev
->this_id
.value
.code_addr
);
1710 fprintf_unfiltered (gdb_stdlog
, "-> ");
1711 fprint_frame (gdb_stdlog
, prev
);
1712 fprintf_unfiltered (gdb_stdlog
, " } // legacy with confused type\n");
1718 /* Return a structure containing various interesting information
1719 about the frame that called THIS_FRAME. Returns NULL
1720 if there is no such frame. */
1723 get_prev_frame (struct frame_info
*this_frame
)
1725 struct frame_info
*prev_frame
;
1729 fprintf_unfiltered (gdb_stdlog
, "{ get_prev_frame (this_frame=");
1730 if (this_frame
!= NULL
)
1731 fprintf_unfiltered (gdb_stdlog
, "%d", this_frame
->level
);
1733 fprintf_unfiltered (gdb_stdlog
, "<NULL>");
1734 fprintf_unfiltered (gdb_stdlog
, ") ");
1737 /* Return the inner-most frame, when the caller passes in NULL. */
1738 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
1739 caller should have previously obtained a valid frame using
1740 get_selected_frame() and then called this code - only possibility
1741 I can think of is code behaving badly.
1743 NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
1744 block_innermost_frame(). It does the sequence: frame = NULL;
1745 while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
1746 it couldn't be written better, I don't know.
1748 NOTE: cagney/2003-01-11: I suspect what is happening is
1749 block_innermost_frame() is, when the target has no state
1750 (registers, memory, ...), still calling this function. The
1751 assumption being that this function will return NULL indicating
1752 that a frame isn't possible, rather than checking that the target
1753 has state and then calling get_current_frame() and
1754 get_prev_frame(). This is a guess mind. */
1755 if (this_frame
== NULL
)
1757 /* NOTE: cagney/2002-11-09: There was a code segment here that
1758 would error out when CURRENT_FRAME was NULL. The comment
1759 that went with it made the claim ...
1761 ``This screws value_of_variable, which just wants a nice
1762 clean NULL return from block_innermost_frame if there are no
1763 frames. I don't think I've ever seen this message happen
1764 otherwise. And returning NULL here is a perfectly legitimate
1767 Per the above, this code shouldn't even be called with a NULL
1769 return current_frame
;
1772 /* There is always a frame. If this assertion fails, suspect that
1773 something should be calling get_selected_frame() or
1774 get_current_frame(). */
1775 gdb_assert (this_frame
!= NULL
);
1777 if (this_frame
->level
>= 0
1778 && !backtrace_past_main
1779 && inside_main_func (get_frame_pc (this_frame
)))
1780 /* Don't unwind past main(), bug always unwind the sentinel frame.
1781 Note, this is done _before_ the frame has been marked as
1782 previously unwound. That way if the user later decides to
1783 allow unwinds past main(), that just happens. */
1786 fprintf_unfiltered (gdb_stdlog
, "-> NULL // inside main func }\n");
1790 if (this_frame
->level
> backtrace_limit
)
1792 error ("Backtrace limit of %d exceeded", backtrace_limit
);
1795 /* If we're already inside the entry function for the main objfile,
1796 then it isn't valid. Don't apply this test to a dummy frame -
1797 dummy frame PC's typically land in the entry func. Don't apply
1798 this test to the sentinel frame. Sentinel frames should always
1799 be allowed to unwind. */
1800 /* NOTE: cagney/2003-02-25: Don't enable until someone has found
1801 hard evidence that this is needed. */
1802 /* NOTE: cagney/2003-07-07: Fixed a bug in inside_main_func - wasn't
1803 checking for "main" in the minimal symbols. With that fixed
1804 asm-source tests now stop in "main" instead of halting the
1805 backtrace in wierd and wonderful ways somewhere inside the entry
1806 file. Suspect that deprecated_inside_entry_file and
1807 inside_entry_func tests were added to work around that (now
1809 /* NOTE: cagney/2003-07-15: danielj (if I'm reading it right)
1810 suggested having the inside_entry_func test use the
1811 inside_main_func msymbol trick (along with entry_point_address I
1812 guess) to determine the address range of the start function.
1813 That should provide a far better stopper than the current
1815 /* NOTE: cagney/2003-07-15: Need to add a "set backtrace
1816 beyond-entry-func" command so that this can be selectively
1820 && backtrace_beyond_entry_func
1822 && this_frame
->type
!= DUMMY_FRAME
&& this_frame
->level
>= 0
1823 && inside_entry_func (get_frame_pc (this_frame
)))
1827 fprintf_unfiltered (gdb_stdlog
, "-> ");
1828 fprint_frame (gdb_stdlog
, NULL
);
1829 fprintf_unfiltered (gdb_stdlog
, "// inside entry func }\n");
1834 /* Only try to do the unwind once. */
1835 if (this_frame
->prev_p
)
1839 fprintf_unfiltered (gdb_stdlog
, "-> ");
1840 fprint_frame (gdb_stdlog
, this_frame
->prev
);
1841 fprintf_unfiltered (gdb_stdlog
, " // cached \n");
1843 return this_frame
->prev
;
1845 this_frame
->prev_p
= 1;
1847 /* If we're inside the entry file, it isn't valid. Don't apply this
1848 test to a dummy frame - dummy frame PC's typically land in the
1849 entry file. Don't apply this test to the sentinel frame.
1850 Sentinel frames should always be allowed to unwind. */
1851 /* NOTE: drow/2002-12-25: should there be a way to disable this
1852 check? It assumes a single small entry file, and the way some
1853 debug readers (e.g. dbxread) figure out which object is the
1854 entry file is somewhat hokey. */
1855 /* NOTE: cagney/2003-01-10: If there is a way of disabling this test
1856 then it should probably be moved to before the ->prev_p test,
1858 /* NOTE: vinschen/2003-04-01: Disabled. It turns out that the call
1859 to deprecated_inside_entry_file destroys a meaningful backtrace
1860 under some conditions. E. g. the backtrace tests in the
1861 asm-source testcase are broken for some targets. In this test
1862 the functions are all implemented as part of one file and the
1863 testcase is not necessarily linked with a start file (depending
1864 on the target). What happens is, that the first frame is printed
1865 normaly and following frames are treated as being inside the
1866 enttry file then. This way, only the #0 frame is printed in the
1867 backtrace output. */
1869 && this_frame
->type
!= DUMMY_FRAME
&& this_frame
->level
>= 0
1870 && deprecated_inside_entry_file (get_frame_pc (this_frame
)))
1874 fprintf_unfiltered (gdb_stdlog
, "-> ");
1875 fprint_frame (gdb_stdlog
, NULL
);
1876 fprintf_unfiltered (gdb_stdlog
, " // inside entry file }\n");
1881 /* If any of the old frame initialization methods are around, use
1882 the legacy get_prev_frame method. */
1883 if (legacy_frame_p (current_gdbarch
))
1885 prev_frame
= legacy_get_prev_frame (this_frame
);
1889 /* Check that this frame's ID was valid. If it wasn't, don't try to
1890 unwind to the prev frame. Be careful to not apply this test to
1891 the sentinel frame. */
1892 if (this_frame
->level
>= 0 && !frame_id_p (get_frame_id (this_frame
)))
1896 fprintf_unfiltered (gdb_stdlog
, "-> ");
1897 fprint_frame (gdb_stdlog
, NULL
);
1898 fprintf_unfiltered (gdb_stdlog
, " // this ID is NULL }\n");
1903 /* Check that this frame's ID isn't inner to (younger, below, next)
1904 the next frame. This happens when a frame unwind goes backwards.
1905 Since the sentinel frame doesn't really exist, don't compare the
1906 inner-most against that sentinel. */
1907 if (this_frame
->level
> 0
1908 && frame_id_inner (get_frame_id (this_frame
),
1909 get_frame_id (this_frame
->next
)))
1910 error ("Previous frame inner to this frame (corrupt stack?)");
1912 /* Check that this and the next frame are not identical. If they
1913 are, there is most likely a stack cycle. As with the inner-than
1914 test above, avoid comparing the inner-most and sentinel frames. */
1915 if (this_frame
->level
> 0
1916 && frame_id_eq (get_frame_id (this_frame
),
1917 get_frame_id (this_frame
->next
)))
1918 error ("Previous frame identical to this frame (corrupt stack?)");
1920 /* Allocate the new frame but do not wire it in to the frame chain.
1921 Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
1922 frame->next to pull some fancy tricks (of course such code is, by
1923 definition, recursive). Try to prevent it.
1925 There is no reason to worry about memory leaks, should the
1926 remainder of the function fail. The allocated memory will be
1927 quickly reclaimed when the frame cache is flushed, and the `we've
1928 been here before' check above will stop repeated memory
1929 allocation calls. */
1930 prev_frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
1931 prev_frame
->level
= this_frame
->level
+ 1;
1933 /* Try to unwind the PC. If that doesn't work, assume we've reached
1934 the oldest frame and simply return. Is there a better sentinal
1935 value? The unwound PC value is then used to initialize the new
1936 previous frame's type.
1938 Note that the pc-unwind is intentionally performed before the
1939 frame chain. This is ok since, for old targets, both
1940 frame_pc_unwind (nee, FRAME_SAVED_PC) and
1941 DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
1942 have already been initialized (using
1943 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1946 By unwinding the PC first, it becomes possible to, in the case of
1947 a dummy frame, avoid also unwinding the frame ID. This is
1948 because (well ignoring the PPC) a dummy frame can be located
1949 using THIS_FRAME's frame ID. */
1951 if (frame_pc_unwind (this_frame
) == 0)
1953 /* The allocated PREV_FRAME will be reclaimed when the frame
1954 obstack is next purged. */
1957 fprintf_unfiltered (gdb_stdlog
, "-> ");
1958 fprint_frame (gdb_stdlog
, NULL
);
1959 fprintf_unfiltered (gdb_stdlog
, " // unwound PC zero }\n");
1964 /* Don't yet compute ->unwind (and hence ->type). It is computed
1965 on-demand in get_frame_type, frame_register_unwind, and
1968 /* Don't yet compute the frame's ID. It is computed on-demand by
1971 /* The unwound frame ID is validate at the start of this function,
1972 as part of the logic to decide if that frame should be further
1973 unwound, and not here while the prev frame is being created.
1974 Doing this makes it possible for the user to examine a frame that
1975 has an invalid frame ID.
1977 Some very old VAX code noted: [...] For the sake of argument,
1978 suppose that the stack is somewhat trashed (which is one reason
1979 that "info frame" exists). So, return 0 (indicating we don't
1980 know the address of the arglist) if we don't know what frame this
1984 this_frame
->prev
= prev_frame
;
1985 prev_frame
->next
= this_frame
;
1989 fprintf_unfiltered (gdb_stdlog
, "-> ");
1990 fprint_frame (gdb_stdlog
, prev_frame
);
1991 fprintf_unfiltered (gdb_stdlog
, " }\n");
1998 get_frame_pc (struct frame_info
*frame
)
2000 gdb_assert (frame
->next
!= NULL
);
2001 return frame_pc_unwind (frame
->next
);
2004 /* Return an address of that falls within the frame's code block. */
2007 frame_unwind_address_in_block (struct frame_info
*next_frame
)
2009 /* A draft address. */
2010 CORE_ADDR pc
= frame_pc_unwind (next_frame
);
2012 /* If THIS frame is not inner most (i.e., NEXT isn't the sentinel),
2013 and NEXT is `normal' (i.e., not a sigtramp, dummy, ....) THIS
2014 frame's PC ends up pointing at the instruction fallowing the
2015 "call". Adjust that PC value so that it falls on the call
2016 instruction (which, hopefully, falls within THIS frame's code
2017 block. So far it's proved to be a very good approximation. See
2018 get_frame_type for why ->type can't be used. */
2019 if (next_frame
->level
>= 0
2020 && get_frame_type (next_frame
) == NORMAL_FRAME
)
2026 get_frame_address_in_block (struct frame_info
*this_frame
)
2028 return frame_unwind_address_in_block (this_frame
->next
);
2032 pc_notcurrent (struct frame_info
*frame
)
2034 /* If FRAME is not the innermost frame, that normally means that
2035 FRAME->pc points at the return instruction (which is *after* the
2036 call instruction), and we want to get the line containing the
2037 call (because the call is where the user thinks the program is).
2038 However, if the next frame is either a SIGTRAMP_FRAME or a
2039 DUMMY_FRAME, then the next frame will contain a saved interrupt
2040 PC and such a PC indicates the current (rather than next)
2041 instruction/line, consequently, for such cases, want to get the
2042 line containing fi->pc. */
2043 struct frame_info
*next
= get_next_frame (frame
);
2044 int notcurrent
= (next
!= NULL
&& get_frame_type (next
) == NORMAL_FRAME
);
2049 find_frame_sal (struct frame_info
*frame
, struct symtab_and_line
*sal
)
2051 (*sal
) = find_pc_line (get_frame_pc (frame
), pc_notcurrent (frame
));
2054 /* Per "frame.h", return the ``address'' of the frame. Code should
2055 really be using get_frame_id(). */
2057 get_frame_base (struct frame_info
*fi
)
2059 return get_frame_id (fi
).stack_addr
;
2062 /* High-level offsets into the frame. Used by the debug info. */
2065 get_frame_base_address (struct frame_info
*fi
)
2067 if (get_frame_type (fi
) != NORMAL_FRAME
)
2069 if (fi
->base
== NULL
)
2070 fi
->base
= frame_base_find_by_frame (fi
->next
);
2071 /* Sneaky: If the low-level unwind and high-level base code share a
2072 common unwinder, let them share the prologue cache. */
2073 if (fi
->base
->unwind
== fi
->unwind
)
2074 return fi
->base
->this_base (fi
->next
, &fi
->prologue_cache
);
2075 return fi
->base
->this_base (fi
->next
, &fi
->base_cache
);
2079 get_frame_locals_address (struct frame_info
*fi
)
2082 if (get_frame_type (fi
) != NORMAL_FRAME
)
2084 /* If there isn't a frame address method, find it. */
2085 if (fi
->base
== NULL
)
2086 fi
->base
= frame_base_find_by_frame (fi
->next
);
2087 /* Sneaky: If the low-level unwind and high-level base code share a
2088 common unwinder, let them share the prologue cache. */
2089 if (fi
->base
->unwind
== fi
->unwind
)
2090 cache
= &fi
->prologue_cache
;
2092 cache
= &fi
->base_cache
;
2093 return fi
->base
->this_locals (fi
->next
, cache
);
2097 get_frame_args_address (struct frame_info
*fi
)
2100 if (get_frame_type (fi
) != NORMAL_FRAME
)
2102 /* If there isn't a frame address method, find it. */
2103 if (fi
->base
== NULL
)
2104 fi
->base
= frame_base_find_by_frame (fi
->next
);
2105 /* Sneaky: If the low-level unwind and high-level base code share a
2106 common unwinder, let them share the prologue cache. */
2107 if (fi
->base
->unwind
== fi
->unwind
)
2108 cache
= &fi
->prologue_cache
;
2110 cache
= &fi
->base_cache
;
2111 return fi
->base
->this_args (fi
->next
, cache
);
2114 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
2115 or -1 for a NULL frame. */
2118 frame_relative_level (struct frame_info
*fi
)
2127 get_frame_type (struct frame_info
*frame
)
2129 /* Some targets still don't use [generic] dummy frames. Catch them
2131 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
2132 && deprecated_frame_in_dummy (frame
))
2135 /* Some legacy code, e.g, mips_init_extra_frame_info() wants
2136 to determine the frame's type prior to it being completely
2137 initialized. Don't attempt to lazily initialize ->unwind for
2138 legacy code. It will be initialized in legacy_get_prev_frame(). */
2139 if (frame
->unwind
== NULL
&& !legacy_frame_p (current_gdbarch
))
2141 /* Initialize the frame's unwinder because it is that which
2142 provides the frame's type. */
2143 frame
->unwind
= frame_unwind_find_by_frame (frame
->next
);
2144 /* FIXME: cagney/2003-04-02: Rather than storing the frame's
2145 type in the frame, the unwinder's type should be returned
2146 directly. Unfortunatly, legacy code, called by
2147 legacy_get_prev_frame, explicitly set the frames type using
2148 the method deprecated_set_frame_type(). */
2149 gdb_assert (frame
->unwind
->type
!= UNKNOWN_FRAME
);
2150 frame
->type
= frame
->unwind
->type
;
2152 if (frame
->type
== UNKNOWN_FRAME
)
2153 return NORMAL_FRAME
;
2159 deprecated_set_frame_type (struct frame_info
*frame
, enum frame_type type
)
2161 /* Arrrg! See comment in "frame.h". */
2165 struct frame_extra_info
*
2166 get_frame_extra_info (struct frame_info
*fi
)
2168 return fi
->extra_info
;
2171 struct frame_extra_info
*
2172 frame_extra_info_zalloc (struct frame_info
*fi
, long size
)
2174 fi
->extra_info
= frame_obstack_zalloc (size
);
2175 return fi
->extra_info
;
2179 deprecated_update_frame_pc_hack (struct frame_info
*frame
, CORE_ADDR pc
)
2182 fprintf_unfiltered (gdb_stdlog
,
2183 "{ deprecated_update_frame_pc_hack (frame=%d,pc=0x%s) }\n",
2184 frame
->level
, paddr_nz (pc
));
2185 /* NOTE: cagney/2003-03-11: Some architectures (e.g., Arm) are
2186 maintaining a locally allocated frame object. Since such frame's
2187 are not in the frame chain, it isn't possible to assume that the
2188 frame has a next. Sigh. */
2189 if (frame
->next
!= NULL
)
2191 /* While we're at it, update this frame's cached PC value, found
2192 in the next frame. Oh for the day when "struct frame_info"
2193 is opaque and this hack on hack can just go away. */
2194 frame
->next
->prev_pc
.value
= pc
;
2195 frame
->next
->prev_pc
.p
= 1;
2200 deprecated_update_frame_base_hack (struct frame_info
*frame
, CORE_ADDR base
)
2203 fprintf_unfiltered (gdb_stdlog
,
2204 "{ deprecated_update_frame_base_hack (frame=%d,base=0x%s) }\n",
2205 frame
->level
, paddr_nz (base
));
2206 /* See comment in "frame.h". */
2207 frame
->this_id
.value
.stack_addr
= base
;
2211 deprecated_set_frame_saved_regs_hack (struct frame_info
*frame
,
2212 CORE_ADDR
*saved_regs
)
2214 frame
->saved_regs
= saved_regs
;
2218 deprecated_set_frame_extra_info_hack (struct frame_info
*frame
,
2219 struct frame_extra_info
*extra_info
)
2221 frame
->extra_info
= extra_info
;
2225 deprecated_set_frame_next_hack (struct frame_info
*fi
,
2226 struct frame_info
*next
)
2232 deprecated_set_frame_prev_hack (struct frame_info
*fi
,
2233 struct frame_info
*prev
)
2239 deprecated_get_frame_context (struct frame_info
*fi
)
2245 deprecated_set_frame_context (struct frame_info
*fi
,
2246 struct context
*context
)
2248 fi
->context
= context
;
2252 deprecated_frame_xmalloc (void)
2254 struct frame_info
*frame
= XMALLOC (struct frame_info
);
2255 memset (frame
, 0, sizeof (*frame
));
2256 frame
->this_id
.p
= 1;
2261 deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs
,
2262 long sizeof_extra_info
)
2264 struct frame_info
*frame
= deprecated_frame_xmalloc ();
2265 make_cleanup (xfree
, frame
);
2266 if (sizeof_saved_regs
> 0)
2268 frame
->saved_regs
= xcalloc (1, sizeof_saved_regs
);
2269 make_cleanup (xfree
, frame
->saved_regs
);
2271 if (sizeof_extra_info
> 0)
2273 frame
->extra_info
= xcalloc (1, sizeof_extra_info
);
2274 make_cleanup (xfree
, frame
->extra_info
);
2279 /* Memory access methods. */
2282 get_frame_memory (struct frame_info
*this_frame
, CORE_ADDR addr
, void *buf
,
2285 read_memory (addr
, buf
, len
);
2289 get_frame_memory_signed (struct frame_info
*this_frame
, CORE_ADDR addr
,
2292 return read_memory_integer (addr
, len
);
2296 get_frame_memory_unsigned (struct frame_info
*this_frame
, CORE_ADDR addr
,
2299 return read_memory_unsigned_integer (addr
, len
);
2302 /* Architecture method. */
2305 get_frame_arch (struct frame_info
*this_frame
)
2307 return current_gdbarch
;
2310 /* Stack pointer methods. */
2313 get_frame_sp (struct frame_info
*this_frame
)
2315 return frame_sp_unwind (this_frame
->next
);
2319 frame_sp_unwind (struct frame_info
*next_frame
)
2321 /* Normality, an architecture that provides a way of obtaining any
2322 frame inner-most address. */
2323 if (gdbarch_unwind_sp_p (current_gdbarch
))
2324 return gdbarch_unwind_sp (current_gdbarch
, next_frame
);
2325 /* Things are looking grim. If it's the inner-most frame and there
2326 is a TARGET_READ_SP then that can be used. */
2327 if (next_frame
->level
< 0 && TARGET_READ_SP_P ())
2328 return TARGET_READ_SP ();
2329 /* Now things are really are grim. Hope that the value returned by
2330 the SP_REGNUM register is meaningful. */
2334 frame_unwind_unsigned_register (next_frame
, SP_REGNUM
, &sp
);
2337 internal_error (__FILE__
, __LINE__
, "Missing unwind SP method");
2342 legacy_frame_p (struct gdbarch
*current_gdbarch
)
2344 return (DEPRECATED_INIT_FRAME_PC_P ()
2345 || DEPRECATED_INIT_FRAME_PC_FIRST_P ()
2346 || DEPRECATED_INIT_EXTRA_FRAME_INFO_P ()
2347 || DEPRECATED_FRAME_CHAIN_P ()
2348 || !gdbarch_unwind_dummy_id_p (current_gdbarch
));
2351 extern initialize_file_ftype _initialize_frame
; /* -Wmissing-prototypes */
2353 static struct cmd_list_element
*set_backtrace_cmdlist
;
2354 static struct cmd_list_element
*show_backtrace_cmdlist
;
2357 set_backtrace_cmd (char *args
, int from_tty
)
2359 help_list (set_backtrace_cmdlist
, "set backtrace ", -1, gdb_stdout
);
2363 show_backtrace_cmd (char *args
, int from_tty
)
2365 cmd_show_list (show_backtrace_cmdlist
, from_tty
, "");
2369 _initialize_frame (void)
2371 obstack_init (&frame_cache_obstack
);
2373 add_prefix_cmd ("backtrace", class_maintenance
, set_backtrace_cmd
, "\
2374 Set backtrace specific variables.\n\
2375 Configure backtrace variables such as the backtrace limit",
2376 &set_backtrace_cmdlist
, "set backtrace ",
2377 0/*allow-unknown*/, &setlist
);
2378 add_prefix_cmd ("backtrace", class_maintenance
, show_backtrace_cmd
, "\
2379 Show backtrace specific variables\n\
2380 Show backtrace variables such as the backtrace limit",
2381 &show_backtrace_cmdlist
, "show backtrace ",
2382 0/*allow-unknown*/, &showlist
);
2384 add_setshow_boolean_cmd ("past-main", class_obscure
,
2385 &backtrace_past_main
, "\
2386 Set whether backtraces should continue past \"main\".\n\
2387 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2388 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2389 of the stack trace.", "\
2390 Show whether backtraces should continue past \"main\".\n\
2391 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
2392 the backtrace at \"main\". Set this variable if you need to see the rest\n\
2393 of the stack trace.",
2394 NULL
, NULL
, &set_backtrace_cmdlist
,
2395 &show_backtrace_cmdlist
);
2397 add_setshow_uinteger_cmd ("limit", class_obscure
,
2398 &backtrace_limit
, "\
2399 Set an upper bound on the number of backtrace levels.\n\
2400 No more than the specified number of frames can be displayed or examined.\n\
2401 Zero is unlimited.", "\
2402 Show the upper bound on the number of backtrace levels.",
2403 NULL
, NULL
, &set_backtrace_cmdlist
,
2404 &show_backtrace_cmdlist
);
2406 /* Debug this files internals. */
2407 add_show_from_set (add_set_cmd ("frame", class_maintenance
, var_zinteger
,
2408 &frame_debug
, "Set frame debugging.\n\
2409 When non-zero, frame specific internal debugging is enabled.", &setdebuglist
),