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 "builtin-regs.h"
32 #include "gdb_obstack.h"
33 #include "dummy-frame.h"
37 #include "frame-unwind.h"
39 /* Return a frame uniq ID that can be used to, later, re-find the
43 get_frame_id (struct frame_info
*fi
)
58 const struct frame_id null_frame_id
; /* All zeros. */
61 frame_id_build (CORE_ADDR base
, CORE_ADDR func_or_pc
)
70 frame_id_p (struct frame_id l
)
72 /* The .func can be NULL but the .base cannot. */
77 frame_id_eq (struct frame_id l
, struct frame_id r
)
79 /* If .base is different, the frames are different. */
82 /* Add a test to check that the frame ID's are for the same function
88 frame_id_inner (struct frame_id l
, struct frame_id r
)
90 /* Only return non-zero when strictly inner than. Note that, per
91 comment in "frame.h", there is some fuzz here. Frameless
92 functions are not strictly inner than (same .base but different
94 return INNER_THAN (l
.base
, r
.base
);
98 frame_find_by_id (struct frame_id id
)
100 struct frame_info
*frame
;
102 /* ZERO denotes the null frame, let the caller decide what to do
103 about it. Should it instead return get_current_frame()? */
104 if (!frame_id_p (id
))
107 for (frame
= get_current_frame ();
109 frame
= get_prev_frame (frame
))
111 struct frame_id
this = get_frame_id (frame
);
112 if (frame_id_eq (id
, this))
113 /* An exact match. */
115 if (frame_id_inner (id
, this))
118 /* Either, we're not yet gone far enough out along the frame
119 chain (inner(this,id), or we're comparing frameless functions
120 (same .base, different .func, no test available). Struggle
121 on until we've definitly gone to far. */
127 frame_pc_unwind (struct frame_info
*frame
)
129 if (!frame
->pc_unwind_cache_p
)
131 frame
->pc_unwind_cache
= frame
->unwind
->pc (frame
, &frame
->unwind_cache
);
132 frame
->pc_unwind_cache_p
= 1;
134 return frame
->pc_unwind_cache
;
138 frame_id_unwind (struct frame_info
*frame
)
140 if (!frame
->id_unwind_cache_p
)
142 frame
->unwind
->id (frame
, &frame
->unwind_cache
, &frame
->id_unwind_cache
);
143 frame
->id_unwind_cache_p
= 1;
145 return frame
->id_unwind_cache
;
150 frame_register_unwind (struct frame_info
*frame
, int regnum
,
151 int *optimizedp
, enum lval_type
*lvalp
,
152 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
154 struct frame_unwind_cache
*cache
;
156 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
157 that the value proper does not need to be fetched. */
158 gdb_assert (optimizedp
!= NULL
);
159 gdb_assert (lvalp
!= NULL
);
160 gdb_assert (addrp
!= NULL
);
161 gdb_assert (realnump
!= NULL
);
162 /* gdb_assert (bufferp != NULL); */
164 /* NOTE: cagney/2002-04-14: It would be nice if, instead of a
165 special case, there was always an inner frame dedicated to the
166 hardware registers. Unfortunatly, there is too much unwind code
167 around that looks up/down the frame chain while making the
168 assumption that each frame level is using the same unwind code. */
172 /* We're in the inner-most frame, get the value direct from the
175 *lvalp
= lval_register
;
176 /* ULGH! Code uses the offset into the raw register byte array
177 as a way of identifying a register. */
178 *addrp
= REGISTER_BYTE (regnum
);
179 /* Should this code test ``register_cached (regnum) < 0'' and do
180 something like set realnum to -1 when the register isn't
184 deprecated_read_register_gen (regnum
, bufferp
);
188 /* Ask this frame to unwind its register. */
189 frame
->unwind
->reg (frame
, &frame
->unwind_cache
, regnum
,
190 optimizedp
, lvalp
, addrp
, realnump
, bufferp
);
194 frame_register (struct frame_info
*frame
, int regnum
,
195 int *optimizedp
, enum lval_type
*lvalp
,
196 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
198 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
199 that the value proper does not need to be fetched. */
200 gdb_assert (optimizedp
!= NULL
);
201 gdb_assert (lvalp
!= NULL
);
202 gdb_assert (addrp
!= NULL
);
203 gdb_assert (realnump
!= NULL
);
204 /* gdb_assert (bufferp != NULL); */
206 /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
207 of the register in the register cache. It should instead return
208 the REGNUM corresponding to that register. Translate the . */
209 if (GET_SAVED_REGISTER_P ())
211 GET_SAVED_REGISTER (bufferp
, optimizedp
, addrp
, frame
, regnum
, lvalp
);
212 /* Compute the REALNUM if the caller wants it. */
213 if (*lvalp
== lval_register
)
216 for (regnum
= 0; regnum
< NUM_REGS
+ NUM_PSEUDO_REGS
; regnum
++)
218 if (*addrp
== register_offset_hack (current_gdbarch
, regnum
))
224 internal_error (__FILE__
, __LINE__
,
225 "Failed to compute the register number corresponding"
226 " to 0x%s", paddr_d (*addrp
));
232 /* Reached the the bottom (youngest, inner most) of the frame chain
233 (youngest, inner most) frame, go direct to the hardware register
234 cache (do not pass go, do not try to cache the value, ...). The
235 unwound value would have been cached in frame->next but that
236 doesn't exist. This doesn't matter as the hardware register
237 cache is stopping any unnecessary accesses to the target. */
239 /* NOTE: cagney/2002-04-14: It would be nice if, instead of a
240 special case, there was always an inner frame dedicated to the
241 hardware registers. Unfortunatly, there is too much unwind code
242 around that looks up/down the frame chain while making the
243 assumption that each frame level is using the same unwind code. */
246 frame_register_unwind (NULL
, regnum
, optimizedp
, lvalp
, addrp
, realnump
,
249 frame_register_unwind (frame
->next
, regnum
, optimizedp
, lvalp
, addrp
,
254 frame_unwind_signed_register (struct frame_info
*frame
, int regnum
,
261 void *buf
= alloca (MAX_REGISTER_RAW_SIZE
);
262 frame_register_unwind (frame
, regnum
, &optimized
, &lval
, &addr
,
264 (*val
) = extract_signed_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
268 frame_unwind_unsigned_register (struct frame_info
*frame
, int regnum
,
275 void *buf
= alloca (MAX_REGISTER_RAW_SIZE
);
276 frame_register_unwind (frame
, regnum
, &optimized
, &lval
, &addr
,
278 (*val
) = extract_unsigned_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
282 frame_read_unsigned_register (struct frame_info
*frame
, int regnum
,
285 /* NOTE: cagney/2002-10-31: There is a bit of dogma here - there is
286 always a frame. Both this, and the equivalent
287 frame_read_signed_register() function, can only be called with a
288 valid frame. If, for some reason, this function is called
289 without a frame then the problem isn't here, but rather in the
290 caller. It should of first created a frame and then passed that
292 /* NOTE: cagney/2002-10-31: As a side bar, keep in mind that the
293 ``current_frame'' should not be treated as a special case. While
294 ``get_next_frame (current_frame) == NULL'' currently holds, it
295 should, as far as possible, not be relied upon. In the future,
296 ``get_next_frame (current_frame)'' may instead simply return a
297 normal frame object that simply always gets register values from
298 the register cache. Consequently, frame code should try to avoid
299 tests like ``if get_next_frame() == NULL'' and instead just rely
300 on recursive frame calls (like the below code) when manipulating
302 gdb_assert (frame
!= NULL
);
303 frame_unwind_unsigned_register (get_next_frame (frame
), regnum
, val
);
307 frame_read_signed_register (struct frame_info
*frame
, int regnum
,
310 /* See note in frame_read_unsigned_register(). */
311 gdb_assert (frame
!= NULL
);
312 frame_unwind_signed_register (get_next_frame (frame
), regnum
, val
);
316 generic_unwind_get_saved_register (char *raw_buffer
,
319 struct frame_info
*frame
,
321 enum lval_type
*lvalp
)
326 enum lval_type lvalx
;
328 if (!target_has_registers
)
329 error ("No registers.");
331 /* Keep things simple, ensure that all the pointers (except valuep)
333 if (optimizedp
== NULL
)
334 optimizedp
= &optimizedx
;
340 /* Reached the the bottom (youngest, inner most) of the frame chain
341 (youngest, inner most) frame, go direct to the hardware register
342 cache (do not pass go, do not try to cache the value, ...). The
343 unwound value would have been cached in frame->next but that
344 doesn't exist. This doesn't matter as the hardware register
345 cache is stopping any unnecessary accesses to the target. */
347 /* NOTE: cagney/2002-04-14: It would be nice if, instead of a
348 special case, there was always an inner frame dedicated to the
349 hardware registers. Unfortunatly, there is too much unwind code
350 around that looks up/down the frame chain while making the
351 assumption that each frame level is using the same unwind code. */
354 frame_register_unwind (NULL
, regnum
, optimizedp
, lvalp
, addrp
, &realnumx
,
357 frame_register_unwind (frame
->next
, regnum
, optimizedp
, lvalp
, addrp
,
358 &realnumx
, raw_buffer
);
362 get_saved_register (char *raw_buffer
,
365 struct frame_info
*frame
,
367 enum lval_type
*lval
)
369 if (GET_SAVED_REGISTER_P ())
371 GET_SAVED_REGISTER (raw_buffer
, optimized
, addrp
, frame
, regnum
, lval
);
374 generic_unwind_get_saved_register (raw_buffer
, optimized
, addrp
, frame
,
378 /* frame_register_read ()
380 Find and return the value of REGNUM for the specified stack frame.
381 The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
383 Returns 0 if the register value could not be found. */
386 frame_register_read (struct frame_info
*frame
, int regnum
, void *myaddr
)
392 frame_register (frame
, regnum
, &optimized
, &lval
, &addr
, &realnum
, myaddr
);
394 /* FIXME: cagney/2002-05-15: This test, is just bogus.
396 It indicates that the target failed to supply a value for a
397 register because it was "not available" at this time. Problem
398 is, the target still has the register and so get saved_register()
399 may be returning a value saved on the stack. */
401 if (register_cached (regnum
) < 0)
402 return 0; /* register value not available */
408 /* Map between a frame register number and its name. A frame register
409 space is a superset of the cooked register space --- it also
410 includes builtin registers. */
413 frame_map_name_to_regnum (const char *name
, int len
)
417 /* Search register name space. */
418 for (i
= 0; i
< NUM_REGS
+ NUM_PSEUDO_REGS
; i
++)
419 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
420 && strncmp (name
, REGISTER_NAME (i
), len
) == 0)
425 /* Try builtin registers. */
426 i
= builtin_reg_map_name_to_regnum (name
, len
);
429 /* A builtin register doesn't fall into the architecture's
431 gdb_assert (i
>= NUM_REGS
+ NUM_PSEUDO_REGS
);
439 frame_map_regnum_to_name (int regnum
)
443 if (regnum
< NUM_REGS
+ NUM_PSEUDO_REGS
)
444 return REGISTER_NAME (regnum
);
445 return builtin_reg_map_regnum_to_name (regnum
);
448 /* Info about the innermost stack frame (contents of FP register) */
450 static struct frame_info
*current_frame
;
452 /* Cache for frame addresses already read by gdb. Valid only while
453 inferior is stopped. Control variables for the frame cache should
454 be local to this module. */
456 static struct obstack frame_cache_obstack
;
459 frame_obstack_zalloc (unsigned long size
)
461 void *data
= obstack_alloc (&frame_cache_obstack
, size
);
462 memset (data
, 0, size
);
467 frame_saved_regs_zalloc (struct frame_info
*fi
)
469 fi
->saved_regs
= (CORE_ADDR
*)
470 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
471 return fi
->saved_regs
;
475 get_frame_saved_regs (struct frame_info
*fi
)
477 return fi
->saved_regs
;
480 /* Return the innermost (currently executing) stack frame. */
483 get_current_frame (void)
485 if (current_frame
== NULL
)
487 if (target_has_stack
)
488 current_frame
= create_new_frame (read_fp (), read_pc ());
492 return current_frame
;
495 /* The "selected" stack frame is used by default for local and arg
496 access. May be zero, for no selected frame. */
498 struct frame_info
*deprecated_selected_frame
;
500 /* Return the selected frame. Always non-null (unless there isn't an
501 inferior sufficient for creating a frame) in which case an error is
505 get_selected_frame (void)
507 if (deprecated_selected_frame
== NULL
)
508 /* Hey! Don't trust this. It should really be re-finding the
509 last selected frame of the currently selected thread. This,
510 though, is better than nothing. */
511 select_frame (get_current_frame ());
512 /* There is always a frame. */
513 gdb_assert (deprecated_selected_frame
!= NULL
);
514 return deprecated_selected_frame
;
517 /* Select frame FI (or NULL - to invalidate the current frame). */
520 select_frame (struct frame_info
*fi
)
522 register struct symtab
*s
;
524 deprecated_selected_frame
= fi
;
525 /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
526 frame is being invalidated. */
527 if (selected_frame_level_changed_hook
)
528 selected_frame_level_changed_hook (frame_relative_level (fi
));
530 /* FIXME: kseitz/2002-08-28: It would be nice to call
531 selected_frame_level_changed_event right here, but due to limitations
532 in the current interfaces, we would end up flooding UIs with events
533 because select_frame is used extensively internally.
535 Once we have frame-parameterized frame (and frame-related) commands,
536 the event notification can be moved here, since this function will only
537 be called when the users selected frame is being changed. */
539 /* Ensure that symbols for this frame are read in. Also, determine the
540 source language of this frame, and switch to it if desired. */
543 s
= find_pc_symtab (fi
->pc
);
545 && s
->language
!= current_language
->la_language
546 && s
->language
!= language_unknown
547 && language_mode
== language_mode_auto
)
549 set_language (s
->language
);
554 /* Return the register saved in the simplistic ``saved_regs'' cache.
555 If the value isn't here AND a value is needed, try the next inner
559 frame_saved_regs_register_unwind (struct frame_info
*frame
, void **cache
,
560 int regnum
, int *optimizedp
,
561 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
562 int *realnump
, void *bufferp
)
564 /* There is always a frame at this point. And THIS is the frame
565 we're interested in. */
566 gdb_assert (frame
!= NULL
);
567 /* If we're using generic dummy frames, we'd better not be in a call
568 dummy. (generic_call_dummy_register_unwind ought to have been called
570 gdb_assert (!(DEPRECATED_USE_GENERIC_DUMMY_FRAMES
571 && (get_frame_type (frame
) == DUMMY_FRAME
)));
573 /* Only (older) architectures that implement the
574 FRAME_INIT_SAVED_REGS method should be using this function. */
575 gdb_assert (FRAME_INIT_SAVED_REGS_P ());
577 /* Load the saved_regs register cache. */
578 if (frame
->saved_regs
== NULL
)
579 FRAME_INIT_SAVED_REGS (frame
);
581 if (frame
->saved_regs
!= NULL
582 && frame
->saved_regs
[regnum
] != 0)
584 if (regnum
== SP_REGNUM
)
586 /* SP register treated specially. */
592 store_address (bufferp
, REGISTER_RAW_SIZE (regnum
),
593 frame
->saved_regs
[regnum
]);
597 /* Any other register is saved in memory, fetch it but cache
598 a local copy of its value. */
600 *lvalp
= lval_memory
;
601 *addrp
= frame
->saved_regs
[regnum
];
606 /* Save each register value, as it is read in, in a
607 frame based cache. */
608 void **regs
= (*cache
);
611 int sizeof_cache
= ((NUM_REGS
+ NUM_PSEUDO_REGS
)
613 regs
= frame_obstack_zalloc (sizeof_cache
);
616 if (regs
[regnum
] == NULL
)
619 = frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum
));
620 read_memory (frame
->saved_regs
[regnum
], regs
[regnum
],
621 REGISTER_RAW_SIZE (regnum
));
623 memcpy (bufferp
, regs
[regnum
], REGISTER_RAW_SIZE (regnum
));
625 /* Read the value in from memory. */
626 read_memory (frame
->saved_regs
[regnum
], bufferp
,
627 REGISTER_RAW_SIZE (regnum
));
634 /* No luck, assume this and the next frame have the same register
635 value. If a value is needed, pass the request on down the chain;
636 otherwise just return an indication that the value is in the same
637 register as the next frame. */
641 *lvalp
= lval_register
;
647 frame_register_unwind (frame
->next
, regnum
, optimizedp
, lvalp
, addrp
,
653 frame_saved_regs_pc_unwind (struct frame_info
*frame
, void **cache
)
655 return FRAME_SAVED_PC (frame
);
659 frame_saved_regs_id_unwind (struct frame_info
*next_frame
, void **cache
,
666 /* Start out by assuming it's NULL. */
667 (*id
) = null_frame_id
;
669 if (next_frame
->next
== NULL
)
670 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
671 the frame chain, not just the inner most frame! The generic,
672 per-architecture, frame code should handle this and the below
673 should simply be removed. */
674 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (next_frame
);
679 /* A frameless inner-most frame. The `FP' (which isn't an
680 architecture frame-pointer register!) of the caller is the same
682 /* FIXME: 2002-11-09: There isn't any reason to special case this
683 edge condition. Instead the per-architecture code should hande
685 base
= get_frame_base (next_frame
);
688 /* Two macros defined in tm.h specify the machine-dependent
689 actions to be performed here.
691 First, get the frame's chain-pointer.
693 If that is zero, the frame is the outermost frame or a leaf
694 called by the outermost frame. This means that if start
695 calls main without a frame, we'll return 0 (which is fine
698 Nope; there's a problem. This also returns when the current
699 routine is a leaf of main. This is unacceptable. We move
700 this to after the ffi test; I'd rather have backtraces from
701 start go curfluy than have an abort called from main not show
703 base
= FRAME_CHAIN (next_frame
);
705 if (!frame_chain_valid (base
, next_frame
))
711 /* FIXME: cagney/2002-06-08: This should probably return the frame's
712 function and not the PC (a.k.a. resume address). */
713 pc
= frame_pc_unwind (next_frame
);
718 const struct frame_unwind trad_frame_unwinder
= {
719 frame_saved_regs_pc_unwind
,
720 frame_saved_regs_id_unwind
,
721 frame_saved_regs_register_unwind
723 const struct frame_unwind
*trad_frame_unwind
= &trad_frame_unwinder
;
726 /* Function: get_saved_register
727 Find register number REGNUM relative to FRAME and put its (raw,
728 target format) contents in *RAW_BUFFER.
730 Set *OPTIMIZED if the variable was optimized out (and thus can't be
731 fetched). Note that this is never set to anything other than zero
732 in this implementation.
734 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
735 whether the value was fetched from memory, from a register, or in a
736 strange and non-modifiable way (e.g. a frame pointer which was
737 calculated rather than fetched). We will use not_lval for values
738 fetched from generic dummy frames.
740 Set *ADDRP to the address, either in memory or as a REGISTER_BYTE
741 offset into the registers array. If the value is stored in a dummy
742 frame, set *ADDRP to zero.
744 To use this implementation, define a function called
745 "get_saved_register" in your target code, which simply passes all
746 of its arguments to this function.
748 The argument RAW_BUFFER must point to aligned memory. */
751 deprecated_generic_get_saved_register (char *raw_buffer
, int *optimized
,
753 struct frame_info
*frame
, int regnum
,
754 enum lval_type
*lval
)
756 if (!target_has_registers
)
757 error ("No registers.");
759 gdb_assert (FRAME_INIT_SAVED_REGS_P ());
761 /* Normal systems don't optimize out things with register numbers. */
762 if (optimized
!= NULL
)
765 if (addrp
) /* default assumption: not found in memory */
768 /* Note: since the current frame's registers could only have been
769 saved by frames INTERIOR TO the current frame, we skip examining
770 the current frame itself: otherwise, we would be getting the
771 previous frame's registers which were saved by the current frame. */
773 while (frame
&& ((frame
= frame
->next
) != NULL
))
775 if (get_frame_type (frame
) == DUMMY_FRAME
)
777 if (lval
) /* found it in a CALL_DUMMY frame */
780 /* FIXME: cagney/2002-06-26: This should be via the
781 gdbarch_register_read() method so that it, on the fly,
782 constructs either a raw or pseudo register from the raw
784 regcache_raw_read (generic_find_dummy_frame (frame
->pc
,
790 FRAME_INIT_SAVED_REGS (frame
);
791 if (frame
->saved_regs
!= NULL
792 && frame
->saved_regs
[regnum
] != 0)
794 if (lval
) /* found it saved on the stack */
796 if (regnum
== SP_REGNUM
)
798 if (raw_buffer
) /* SP register treated specially */
799 store_address (raw_buffer
, REGISTER_RAW_SIZE (regnum
),
800 frame
->saved_regs
[regnum
]);
804 if (addrp
) /* any other register */
805 *addrp
= frame
->saved_regs
[regnum
];
807 read_memory (frame
->saved_regs
[regnum
], raw_buffer
,
808 REGISTER_RAW_SIZE (regnum
));
814 /* If we get thru the loop to this point, it means the register was
815 not saved in any frame. Return the actual live-register value. */
817 if (lval
) /* found it in a live register */
818 *lval
= lval_register
;
820 *addrp
= REGISTER_BYTE (regnum
);
822 deprecated_read_register_gen (regnum
, raw_buffer
);
825 /* Create an arbitrary (i.e. address specified by user) or innermost frame.
826 Always returns a non-NULL value. */
829 create_new_frame (CORE_ADDR addr
, CORE_ADDR pc
)
831 struct frame_info
*fi
;
832 enum frame_type type
;
834 fi
= frame_obstack_zalloc (sizeof (struct frame_info
));
838 /* NOTE: cagney/2002-11-18: The code segments, found in
839 create_new_frame and get_prev_frame(), that initializes the
840 frames type is subtly different. The latter only updates ->type
841 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
842 get_prev_frame() overriding the frame's type when the INIT code
843 has previously set it. This is really somewhat bogus. The
844 initialization, as seen in create_new_frame(), should occur
845 before the INIT function has been called. */
846 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
847 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
848 ? DEPRECATED_PC_IN_CALL_DUMMY (pc
, 0, 0)
849 : pc_in_dummy_frame (pc
)))
850 /* NOTE: cagney/2002-11-11: Does this even occure? */
855 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
856 if (PC_IN_SIGTRAMP (fi
->pc
, name
))
857 type
= SIGTRAMP_FRAME
;
863 if (INIT_EXTRA_FRAME_INFO_P ())
864 INIT_EXTRA_FRAME_INFO (0, fi
);
866 /* Select/initialize an unwind function. */
867 fi
->unwind
= frame_unwind_find_by_pc (current_gdbarch
, fi
->pc
);
872 /* Return the frame that FRAME calls (NULL if FRAME is the innermost
876 get_next_frame (struct frame_info
*frame
)
881 /* Flush the entire frame cache. */
884 flush_cached_frames (void)
886 /* Since we can't really be sure what the first object allocated was */
887 obstack_free (&frame_cache_obstack
, 0);
888 obstack_init (&frame_cache_obstack
);
890 current_frame
= NULL
; /* Invalidate cache */
892 annotate_frames_invalid ();
895 /* Flush the frame cache, and start a new one if necessary. */
898 reinit_frame_cache (void)
900 flush_cached_frames ();
902 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
903 if (PIDGET (inferior_ptid
) != 0)
905 select_frame (get_current_frame ());
909 /* Return a structure containing various interesting information
910 about the frame that called NEXT_FRAME. Returns NULL
911 if there is no such frame. */
914 get_prev_frame (struct frame_info
*next_frame
)
916 CORE_ADDR address
= 0;
917 struct frame_info
*prev
;
920 /* Return the inner-most frame, when the caller passes in NULL. */
921 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
922 caller should have previously obtained a valid frame using
923 get_selected_frame() and then called this code - only possibility
924 I can think of is code behaving badly. */
925 if (next_frame
== NULL
)
927 /* NOTE: cagney/2002-11-09: There was a code segment here that
928 would error out when CURRENT_FRAME was NULL. The comment
929 that went with it made the claim ...
931 ``This screws value_of_variable, which just wants a nice
932 clean NULL return from block_innermost_frame if there are no
933 frames. I don't think I've ever seen this message happen
934 otherwise. And returning NULL here is a perfectly legitimate
937 Per the above, this code shouldn't even be called with a NULL
939 return current_frame
;
942 /* Only try to do the unwind once. */
943 if (next_frame
->prev_p
)
944 return next_frame
->prev
;
945 next_frame
->prev_p
= 1;
947 /* On some machines it is possible to call a function without
948 setting up a stack frame for it. On these machines, we
949 define this macro to take two args; a frameinfo pointer
950 identifying a frame and a variable to set or clear if it is
951 or isn't leafless. */
953 /* Still don't want to worry about this except on the innermost
954 frame. This macro will set FROMLEAF if NEXT_FRAME is a frameless
955 function invocation. */
956 if (next_frame
->next
== NULL
)
957 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
958 the frame chain, not just the inner most frame! The generic,
959 per-architecture, frame code should handle this and the below
960 should simply be removed. */
961 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (next_frame
);
966 /* A frameless inner-most frame. The `FP' (which isn't an
967 architecture frame-pointer register!) of the caller is the same
969 /* FIXME: 2002-11-09: There isn't any reason to special case this
970 edge condition. Instead the per-architecture code should hande
972 address
= get_frame_base (next_frame
);
975 /* Two macros defined in tm.h specify the machine-dependent
976 actions to be performed here.
978 First, get the frame's chain-pointer.
980 If that is zero, the frame is the outermost frame or a leaf
981 called by the outermost frame. This means that if start
982 calls main without a frame, we'll return 0 (which is fine
985 Nope; there's a problem. This also returns when the current
986 routine is a leaf of main. This is unacceptable. We move
987 this to after the ffi test; I'd rather have backtraces from
988 start go curfluy than have an abort called from main not show
990 address
= FRAME_CHAIN (next_frame
);
992 if (!frame_chain_valid (address
, next_frame
))
998 /* Create an initially zero previous frame. */
999 prev
= frame_obstack_zalloc (sizeof (struct frame_info
));
1002 next_frame
->prev
= prev
;
1003 prev
->next
= next_frame
;
1004 prev
->frame
= address
;
1005 prev
->level
= next_frame
->level
+ 1;
1006 /* FIXME: cagney/2002-11-18: Should be setting the frame's type
1007 here, before anything else, and not last. Various INIT functions
1008 are full of work-arounds for the frames type not being set
1009 correctly from the word go. Ulgh! */
1010 prev
->type
= NORMAL_FRAME
;
1012 /* This change should not be needed, FIXME! We should determine
1013 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1014 after INIT_EXTRA_FRAME_INFO and come up with a simple way to
1015 express what goes on here.
1017 INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame
1018 (where the PC is already set up) and here (where it isn't).
1019 DEPRECATED_INIT_FRAME_PC is only called from here, always after
1020 INIT_EXTRA_FRAME_INFO.
1022 The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the
1023 PC value (which hasn't been set yet). Some other machines appear
1024 to require INIT_EXTRA_FRAME_INFO before they can do
1025 DEPRECATED_INIT_FRAME_PC. Phoo.
1027 We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
1028 complication to an already overcomplicated part of GDB.
1029 gnu@cygnus.com, 15Sep92.
1031 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
1032 INIT_EXTRA_FRAME_INFO, one possible scheme:
1034 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1035 (read_fp ()), read_pc ()). Machines with extra frame info would
1036 do that (or the local equivalent) and then set the extra fields.
1038 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1039 create_new_frame would no longer init extra frame info;
1040 SETUP_ARBITRARY_FRAME would have to do that.
1042 INIT_PREV_FRAME(fromleaf, prev) Replace INIT_EXTRA_FRAME_INFO and
1043 DEPRECATED_INIT_FRAME_PC. This should also return a flag saying
1044 whether to keep the new frame, or whether to discard it, because
1045 on some machines (e.g. mips) it is really awkward to have
1046 FRAME_CHAIN_VALID called *before* INIT_EXTRA_FRAME_INFO (there is
1047 no good way to get information deduced in FRAME_CHAIN_VALID into
1048 the extra fields of the new frame). std_frame_pc(fromleaf, prev)
1050 This is the default setting for INIT_PREV_FRAME. It just does
1051 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1052 will call it from INIT_PREV_FRAME (either at the beginning, the
1053 end, or in the middle). Some machines won't use it.
1055 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1057 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1058 reason for things to be this complicated.
1060 The trick is to assume that there is always a frame. Instead of
1061 special casing the inner-most frame, create fake frame
1062 (containing the hardware registers) that is inner to the
1063 user-visible inner-most frame (...) and then unwind from that.
1064 That way architecture code can use use the standard
1065 frame_XX_unwind() functions and not differentiate between the
1066 inner most and any other case.
1068 Since there is always a frame to unwind from, there is always
1069 somewhere (NEXT_FRAME) to store all the info needed to construct
1070 a new (previous) frame without having to first create it. This
1071 means that the convolution below - needing to carefully order a
1072 frame's initialization - isn't needed.
1074 The irony here though, is that FRAME_CHAIN(), at least for a more
1075 up-to-date architecture, always calls FRAME_SAVED_PC(), and
1076 FRAME_SAVED_PC() computes the PC but without first needing the
1077 frame! Instead of the convolution below, we could have simply
1078 called FRAME_SAVED_PC() and been done with it! Note that
1079 FRAME_SAVED_PC() is being superseed by frame_pc_unwind() and that
1080 function does have somewhere to cache that PC value. */
1082 if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
1083 prev
->pc
= (DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf
, prev
));
1085 if (INIT_EXTRA_FRAME_INFO_P ())
1086 INIT_EXTRA_FRAME_INFO (fromleaf
, prev
);
1088 /* This entry is in the frame queue now, which is good since
1089 FRAME_SAVED_PC may use that queue to figure out its value (see
1090 tm-sparc.h). We want the pc saved in the inferior frame. */
1091 if (DEPRECATED_INIT_FRAME_PC_P ())
1092 prev
->pc
= DEPRECATED_INIT_FRAME_PC (fromleaf
, prev
);
1094 /* If ->frame and ->pc are unchanged, we are in the process of
1095 getting ourselves into an infinite backtrace. Some architectures
1096 check this in FRAME_CHAIN or thereabouts, but it seems like there
1097 is no reason this can't be an architecture-independent check. */
1098 if (prev
->frame
== next_frame
->frame
1099 && prev
->pc
== next_frame
->pc
)
1101 next_frame
->prev
= NULL
;
1102 obstack_free (&frame_cache_obstack
, prev
);
1106 /* Initialize the code used to unwind the frame PREV based on the PC
1107 (and probably other architectural information). The PC lets you
1108 check things like the debug info at that point (dwarf2cfi?) and
1109 use that to decide how the frame should be unwound. */
1110 prev
->unwind
= frame_unwind_find_by_pc (current_gdbarch
, prev
->pc
);
1112 /* NOTE: cagney/2002-11-18: The code segments, found in
1113 create_new_frame and get_prev_frame(), that initializes the
1114 frames type is subtly different. The latter only updates ->type
1115 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1116 get_prev_frame() overriding the frame's type when the INIT code
1117 has previously set it. This is really somewhat bogus. The
1118 initialization, as seen in create_new_frame(), should occur
1119 before the INIT function has been called. */
1120 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1121 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
1122 ? DEPRECATED_PC_IN_CALL_DUMMY (prev
->pc
, 0, 0)
1123 : pc_in_dummy_frame (prev
->pc
)))
1124 prev
->type
= DUMMY_FRAME
;
1127 /* FIXME: cagney/2002-11-10: This should be moved to before the
1128 INIT code above so that the INIT code knows what the frame's
1129 type is (in fact, for a [generic] dummy-frame, the type can
1130 be set and then the entire initialization can be skipped.
1131 Unforunatly, its the INIT code that sets the PC (Hmm, catch
1134 find_pc_partial_function (prev
->pc
, &name
, NULL
, NULL
);
1135 if (PC_IN_SIGTRAMP (prev
->pc
, name
))
1136 prev
->type
= SIGTRAMP_FRAME
;
1137 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1138 architectures are forcing the frame's type in INIT so we
1139 don't want to override it here. Remember, NORMAL_FRAME == 0,
1140 so it all works (just :-/). Once this initialization is
1141 moved to the start of this function, all this nastness will
1149 get_frame_pc (struct frame_info
*frame
)
1155 pc_notcurrent (struct frame_info
*frame
)
1157 /* If FRAME is not the innermost frame, that normally means that
1158 FRAME->pc points at the return instruction (which is *after* the
1159 call instruction), and we want to get the line containing the
1160 call (because the call is where the user thinks the program is).
1161 However, if the next frame is either a SIGTRAMP_FRAME or a
1162 DUMMY_FRAME, then the next frame will contain a saved interrupt
1163 PC and such a PC indicates the current (rather than next)
1164 instruction/line, consequently, for such cases, want to get the
1165 line containing fi->pc. */
1166 struct frame_info
*next
= get_next_frame (frame
);
1167 int notcurrent
= (next
!= NULL
&& get_frame_type (next
) == NORMAL_FRAME
);
1172 find_frame_sal (struct frame_info
*frame
, struct symtab_and_line
*sal
)
1174 (*sal
) = find_pc_line (frame
->pc
, pc_notcurrent (frame
));
1177 /* Per "frame.h", return the ``address'' of the frame. Code should
1178 really be using get_frame_id(). */
1180 get_frame_base (struct frame_info
*fi
)
1185 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
1186 or -1 for a NULL frame. */
1189 frame_relative_level (struct frame_info
*fi
)
1198 get_frame_type (struct frame_info
*frame
)
1200 /* Some targets still don't use [generic] dummy frames. Catch them
1202 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1203 && deprecated_frame_in_dummy (frame
))
1209 deprecated_set_frame_type (struct frame_info
*frame
, enum frame_type type
)
1211 /* Arrrg! See comment in "frame.h". */
1215 #ifdef FRAME_FIND_SAVED_REGS
1216 /* XXX - deprecated. This is a compatibility function for targets
1217 that do not yet implement FRAME_INIT_SAVED_REGS. */
1218 /* Find the addresses in which registers are saved in FRAME. */
1221 deprecated_get_frame_saved_regs (struct frame_info
*frame
,
1222 struct frame_saved_regs
*saved_regs_addr
)
1224 if (frame
->saved_regs
== NULL
)
1226 frame
->saved_regs
= (CORE_ADDR
*)
1227 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
1229 if (saved_regs_addr
== NULL
)
1231 struct frame_saved_regs saved_regs
;
1232 FRAME_FIND_SAVED_REGS (frame
, saved_regs
);
1233 memcpy (frame
->saved_regs
, &saved_regs
, SIZEOF_FRAME_SAVED_REGS
);
1237 FRAME_FIND_SAVED_REGS (frame
, *saved_regs_addr
);
1238 memcpy (frame
->saved_regs
, saved_regs_addr
, SIZEOF_FRAME_SAVED_REGS
);
1243 struct frame_extra_info
*
1244 get_frame_extra_info (struct frame_info
*fi
)
1246 return fi
->extra_info
;
1249 struct frame_extra_info
*
1250 frame_extra_info_zalloc (struct frame_info
*fi
, long size
)
1252 fi
->extra_info
= frame_obstack_zalloc (size
);
1253 return fi
->extra_info
;
1257 deprecated_update_frame_pc_hack (struct frame_info
*frame
, CORE_ADDR pc
)
1259 /* See comment in "frame.h". */
1264 deprecated_update_frame_base_hack (struct frame_info
*frame
, CORE_ADDR base
)
1266 /* See comment in "frame.h". */
1267 frame
->frame
= base
;
1271 deprecated_set_frame_saved_regs_hack (struct frame_info
*frame
,
1272 CORE_ADDR
*saved_regs
)
1274 frame
->saved_regs
= saved_regs
;
1278 deprecated_set_frame_extra_info_hack (struct frame_info
*frame
,
1279 struct frame_extra_info
*extra_info
)
1281 frame
->extra_info
= extra_info
;
1285 deprecated_set_frame_next_hack (struct frame_info
*fi
,
1286 struct frame_info
*next
)
1292 deprecated_set_frame_prev_hack (struct frame_info
*fi
,
1293 struct frame_info
*prev
)
1299 deprecated_get_frame_context (struct frame_info
*fi
)
1305 deprecated_set_frame_context (struct frame_info
*fi
,
1306 struct context
*context
)
1308 fi
->context
= context
;
1312 deprecated_frame_xmalloc (void)
1314 struct frame_info
*frame
= XMALLOC (struct frame_info
);
1315 memset (frame
, 0, sizeof (struct frame_info
));
1320 deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs
,
1321 long sizeof_extra_info
)
1323 struct frame_info
*frame
= deprecated_frame_xmalloc ();
1324 make_cleanup (xfree
, frame
);
1325 if (sizeof_saved_regs
> 0)
1327 frame
->saved_regs
= xcalloc (1, sizeof_saved_regs
);
1328 make_cleanup (xfree
, frame
->saved_regs
);
1330 if (sizeof_extra_info
> 0)
1332 frame
->extra_info
= xcalloc (1, sizeof_extra_info
);
1333 make_cleanup (xfree
, frame
->extra_info
);
1339 _initialize_frame (void)
1341 obstack_init (&frame_cache_obstack
);