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"
38 /* Return a frame uniq ID that can be used to, later, re-find the
42 get_frame_id (struct frame_info
*fi
)
57 const struct frame_id null_frame_id
; /* All zeros. */
60 frame_id_build (CORE_ADDR base
, CORE_ADDR func_or_pc
)
69 frame_id_p (struct frame_id l
)
71 /* The .func can be NULL but the .base cannot. */
76 frame_id_eq (struct frame_id l
, struct frame_id r
)
78 /* If .base is different, the frames are different. */
81 /* Add a test to check that the frame ID's are for the same function
87 frame_id_inner (struct frame_id l
, struct frame_id r
)
89 /* Only return non-zero when strictly inner than. Note that, per
90 comment in "frame.h", there is some fuzz here. Frameless
91 functions are not strictly inner than (same .base but different
93 return INNER_THAN (l
.base
, r
.base
);
97 frame_find_by_id (struct frame_id id
)
99 struct frame_info
*frame
;
101 /* ZERO denotes the null frame, let the caller decide what to do
102 about it. Should it instead return get_current_frame()? */
103 if (!frame_id_p (id
))
106 for (frame
= get_current_frame ();
108 frame
= get_prev_frame (frame
))
110 struct frame_id
this = get_frame_id (frame
);
111 if (frame_id_eq (id
, this))
112 /* An exact match. */
114 if (frame_id_inner (id
, this))
117 /* Either, we're not yet gone far enough out along the frame
118 chain (inner(this,id), or we're comparing frameless functions
119 (same .base, different .func, no test available). Struggle
120 on until we've definitly gone to far. */
126 frame_pc_unwind (struct frame_info
*frame
)
128 if (!frame
->pc_unwind_cache_p
)
130 frame
->pc_unwind_cache
= frame
->pc_unwind (frame
, &frame
->unwind_cache
);
131 frame
->pc_unwind_cache_p
= 1;
133 return frame
->pc_unwind_cache
;
137 frame_id_unwind (struct frame_info
*frame
)
139 if (!frame
->id_unwind_cache_p
)
141 frame
->id_unwind_cache
=
142 frame
->id_unwind (frame
, &frame
->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
->register_unwind (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
);
658 static struct frame_id
659 frame_saved_regs_id_unwind (struct frame_info
*next_frame
, void **cache
)
664 if (next_frame
->next
== NULL
)
665 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
666 the frame chain, not just the inner most frame! The generic,
667 per-architecture, frame code should handle this and the below
668 should simply be removed. */
669 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (next_frame
);
674 /* A frameless inner-most frame. The `FP' (which isn't an
675 architecture frame-pointer register!) of the caller is the same
677 /* FIXME: 2002-11-09: There isn't any reason to special case this
678 edge condition. Instead the per-architecture code should hande
680 id
.base
= get_frame_base (next_frame
);
683 /* Two macros defined in tm.h specify the machine-dependent
684 actions to be performed here.
686 First, get the frame's chain-pointer.
688 If that is zero, the frame is the outermost frame or a leaf
689 called by the outermost frame. This means that if start
690 calls main without a frame, we'll return 0 (which is fine
693 Nope; there's a problem. This also returns when the current
694 routine is a leaf of main. This is unacceptable. We move
695 this to after the ffi test; I'd rather have backtraces from
696 start go curfluy than have an abort called from main not show
698 id
.base
= FRAME_CHAIN (next_frame
);
700 if (!frame_chain_valid (id
.base
, next_frame
))
701 return null_frame_id
;
704 return null_frame_id
;
706 /* FIXME: cagney/2002-06-08: This should probably return the frame's
707 function and not the PC (a.k.a. resume address). */
708 id
.pc
= frame_pc_unwind (next_frame
);
712 /* Function: get_saved_register
713 Find register number REGNUM relative to FRAME and put its (raw,
714 target format) contents in *RAW_BUFFER.
716 Set *OPTIMIZED if the variable was optimized out (and thus can't be
717 fetched). Note that this is never set to anything other than zero
718 in this implementation.
720 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
721 whether the value was fetched from memory, from a register, or in a
722 strange and non-modifiable way (e.g. a frame pointer which was
723 calculated rather than fetched). We will use not_lval for values
724 fetched from generic dummy frames.
726 Set *ADDRP to the address, either in memory or as a REGISTER_BYTE
727 offset into the registers array. If the value is stored in a dummy
728 frame, set *ADDRP to zero.
730 To use this implementation, define a function called
731 "get_saved_register" in your target code, which simply passes all
732 of its arguments to this function.
734 The argument RAW_BUFFER must point to aligned memory. */
737 deprecated_generic_get_saved_register (char *raw_buffer
, int *optimized
,
739 struct frame_info
*frame
, int regnum
,
740 enum lval_type
*lval
)
742 if (!target_has_registers
)
743 error ("No registers.");
745 gdb_assert (FRAME_INIT_SAVED_REGS_P ());
747 /* Normal systems don't optimize out things with register numbers. */
748 if (optimized
!= NULL
)
751 if (addrp
) /* default assumption: not found in memory */
754 /* Note: since the current frame's registers could only have been
755 saved by frames INTERIOR TO the current frame, we skip examining
756 the current frame itself: otherwise, we would be getting the
757 previous frame's registers which were saved by the current frame. */
759 while (frame
&& ((frame
= frame
->next
) != NULL
))
761 if (get_frame_type (frame
) == DUMMY_FRAME
)
763 if (lval
) /* found it in a CALL_DUMMY frame */
766 /* FIXME: cagney/2002-06-26: This should be via the
767 gdbarch_register_read() method so that it, on the fly,
768 constructs either a raw or pseudo register from the raw
770 regcache_raw_read (generic_find_dummy_frame (frame
->pc
,
776 FRAME_INIT_SAVED_REGS (frame
);
777 if (frame
->saved_regs
!= NULL
778 && frame
->saved_regs
[regnum
] != 0)
780 if (lval
) /* found it saved on the stack */
782 if (regnum
== SP_REGNUM
)
784 if (raw_buffer
) /* SP register treated specially */
785 store_address (raw_buffer
, REGISTER_RAW_SIZE (regnum
),
786 frame
->saved_regs
[regnum
]);
790 if (addrp
) /* any other register */
791 *addrp
= frame
->saved_regs
[regnum
];
793 read_memory (frame
->saved_regs
[regnum
], raw_buffer
,
794 REGISTER_RAW_SIZE (regnum
));
800 /* If we get thru the loop to this point, it means the register was
801 not saved in any frame. Return the actual live-register value. */
803 if (lval
) /* found it in a live register */
804 *lval
= lval_register
;
806 *addrp
= REGISTER_BYTE (regnum
);
808 deprecated_read_register_gen (regnum
, raw_buffer
);
811 /* Using the PC, select a mechanism for unwinding a frame returning
812 the previous frame. The register unwind function should, on
813 demand, initialize the ->context object. */
816 set_unwind_by_pc (CORE_ADDR pc
, CORE_ADDR fp
,
817 frame_register_unwind_ftype
**unwind_register
,
818 frame_pc_unwind_ftype
**unwind_pc
,
819 frame_id_unwind_ftype
**unwind_id
)
821 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
)
823 /* Still need to set this to something. The ``info frame'' code
824 calls this function to find out where the saved registers are.
825 Hopefully this is robust enough to stop any core dumps and
826 return vaguely correct values.. */
827 *unwind_register
= frame_saved_regs_register_unwind
;
828 *unwind_pc
= frame_saved_regs_pc_unwind
;
829 *unwind_id
= frame_saved_regs_id_unwind
;
831 else if (DEPRECATED_PC_IN_CALL_DUMMY_P ()
832 ? DEPRECATED_PC_IN_CALL_DUMMY (pc
, 0, 0)
833 : pc_in_dummy_frame (pc
))
835 *unwind_register
= dummy_frame_register_unwind
;
836 *unwind_pc
= dummy_frame_pc_unwind
;
837 *unwind_id
= dummy_frame_id_unwind
;
841 *unwind_register
= frame_saved_regs_register_unwind
;
842 *unwind_pc
= frame_saved_regs_pc_unwind
;
843 *unwind_id
= frame_saved_regs_id_unwind
;
847 /* Create an arbitrary (i.e. address specified by user) or innermost frame.
848 Always returns a non-NULL value. */
851 create_new_frame (CORE_ADDR addr
, CORE_ADDR pc
)
853 struct frame_info
*fi
;
854 enum frame_type type
;
856 fi
= frame_obstack_zalloc (sizeof (struct frame_info
));
860 /* NOTE: cagney/2002-11-18: The code segments, found in
861 create_new_frame and get_prev_frame(), that initializes the
862 frames type is subtly different. The latter only updates ->type
863 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
864 get_prev_frame() overriding the frame's type when the INIT code
865 has previously set it. This is really somewhat bogus. The
866 initialization, as seen in create_new_frame(), should occur
867 before the INIT function has been called. */
868 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
869 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
870 ? DEPRECATED_PC_IN_CALL_DUMMY (pc
, 0, 0)
871 : pc_in_dummy_frame (pc
)))
872 /* NOTE: cagney/2002-11-11: Does this even occure? */
877 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
878 if (PC_IN_SIGTRAMP (fi
->pc
, name
))
879 type
= SIGTRAMP_FRAME
;
885 if (INIT_EXTRA_FRAME_INFO_P ())
886 INIT_EXTRA_FRAME_INFO (0, fi
);
888 /* Select/initialize an unwind function. */
889 set_unwind_by_pc (fi
->pc
, fi
->frame
, &fi
->register_unwind
,
890 &fi
->pc_unwind
, &fi
->id_unwind
);
895 /* Return the frame that FRAME calls (NULL if FRAME is the innermost
899 get_next_frame (struct frame_info
*frame
)
904 /* Flush the entire frame cache. */
907 flush_cached_frames (void)
909 /* Since we can't really be sure what the first object allocated was */
910 obstack_free (&frame_cache_obstack
, 0);
911 obstack_init (&frame_cache_obstack
);
913 current_frame
= NULL
; /* Invalidate cache */
915 annotate_frames_invalid ();
918 /* Flush the frame cache, and start a new one if necessary. */
921 reinit_frame_cache (void)
923 flush_cached_frames ();
925 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
926 if (PIDGET (inferior_ptid
) != 0)
928 select_frame (get_current_frame ());
932 /* Return a structure containing various interesting information
933 about the frame that called NEXT_FRAME. Returns NULL
934 if there is no such frame. */
937 get_prev_frame (struct frame_info
*next_frame
)
939 CORE_ADDR address
= 0;
940 struct frame_info
*prev
;
943 /* Return the inner-most frame, when the caller passes in NULL. */
944 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
945 caller should have previously obtained a valid frame using
946 get_selected_frame() and then called this code - only possibility
947 I can think of is code behaving badly. */
948 if (next_frame
== NULL
)
950 /* NOTE: cagney/2002-11-09: There was a code segment here that
951 would error out when CURRENT_FRAME was NULL. The comment
952 that went with it made the claim ...
954 ``This screws value_of_variable, which just wants a nice
955 clean NULL return from block_innermost_frame if there are no
956 frames. I don't think I've ever seen this message happen
957 otherwise. And returning NULL here is a perfectly legitimate
960 Per the above, this code shouldn't even be called with a NULL
962 return current_frame
;
965 /* Only try to do the unwind once. */
966 if (next_frame
->prev_p
)
967 return next_frame
->prev
;
968 next_frame
->prev_p
= 1;
970 /* On some machines it is possible to call a function without
971 setting up a stack frame for it. On these machines, we
972 define this macro to take two args; a frameinfo pointer
973 identifying a frame and a variable to set or clear if it is
974 or isn't leafless. */
976 /* Still don't want to worry about this except on the innermost
977 frame. This macro will set FROMLEAF if NEXT_FRAME is a frameless
978 function invocation. */
979 if (next_frame
->next
== NULL
)
980 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
981 the frame chain, not just the inner most frame! The generic,
982 per-architecture, frame code should handle this and the below
983 should simply be removed. */
984 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (next_frame
);
989 /* A frameless inner-most frame. The `FP' (which isn't an
990 architecture frame-pointer register!) of the caller is the same
992 /* FIXME: 2002-11-09: There isn't any reason to special case this
993 edge condition. Instead the per-architecture code should hande
995 address
= get_frame_base (next_frame
);
998 /* Two macros defined in tm.h specify the machine-dependent
999 actions to be performed here.
1001 First, get the frame's chain-pointer.
1003 If that is zero, the frame is the outermost frame or a leaf
1004 called by the outermost frame. This means that if start
1005 calls main without a frame, we'll return 0 (which is fine
1008 Nope; there's a problem. This also returns when the current
1009 routine is a leaf of main. This is unacceptable. We move
1010 this to after the ffi test; I'd rather have backtraces from
1011 start go curfluy than have an abort called from main not show
1013 address
= FRAME_CHAIN (next_frame
);
1015 if (!frame_chain_valid (address
, next_frame
))
1021 /* Create an initially zero previous frame. */
1022 prev
= frame_obstack_zalloc (sizeof (struct frame_info
));
1025 next_frame
->prev
= prev
;
1026 prev
->next
= next_frame
;
1027 prev
->frame
= address
;
1028 prev
->level
= next_frame
->level
+ 1;
1029 /* FIXME: cagney/2002-11-18: Should be setting the frame's type
1030 here, before anything else, and not last. Various INIT functions
1031 are full of work-arounds for the frames type not being set
1032 correctly from the word go. Ulgh! */
1033 prev
->type
= NORMAL_FRAME
;
1035 /* This change should not be needed, FIXME! We should determine
1036 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1037 after INIT_EXTRA_FRAME_INFO and come up with a simple way to
1038 express what goes on here.
1040 INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame
1041 (where the PC is already set up) and here (where it isn't).
1042 DEPRECATED_INIT_FRAME_PC is only called from here, always after
1043 INIT_EXTRA_FRAME_INFO.
1045 The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the
1046 PC value (which hasn't been set yet). Some other machines appear
1047 to require INIT_EXTRA_FRAME_INFO before they can do
1048 DEPRECATED_INIT_FRAME_PC. Phoo.
1050 We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
1051 complication to an already overcomplicated part of GDB.
1052 gnu@cygnus.com, 15Sep92.
1054 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
1055 INIT_EXTRA_FRAME_INFO, one possible scheme:
1057 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1058 (read_fp ()), read_pc ()). Machines with extra frame info would
1059 do that (or the local equivalent) and then set the extra fields.
1061 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1062 create_new_frame would no longer init extra frame info;
1063 SETUP_ARBITRARY_FRAME would have to do that.
1065 INIT_PREV_FRAME(fromleaf, prev) Replace INIT_EXTRA_FRAME_INFO and
1066 DEPRECATED_INIT_FRAME_PC. This should also return a flag saying
1067 whether to keep the new frame, or whether to discard it, because
1068 on some machines (e.g. mips) it is really awkward to have
1069 FRAME_CHAIN_VALID called *before* INIT_EXTRA_FRAME_INFO (there is
1070 no good way to get information deduced in FRAME_CHAIN_VALID into
1071 the extra fields of the new frame). std_frame_pc(fromleaf, prev)
1073 This is the default setting for INIT_PREV_FRAME. It just does
1074 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1075 will call it from INIT_PREV_FRAME (either at the beginning, the
1076 end, or in the middle). Some machines won't use it.
1078 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1080 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1081 reason for things to be this complicated.
1083 The trick is to assume that there is always a frame. Instead of
1084 special casing the inner-most frame, create fake frame
1085 (containing the hardware registers) that is inner to the
1086 user-visible inner-most frame (...) and then unwind from that.
1087 That way architecture code can use use the standard
1088 frame_XX_unwind() functions and not differentiate between the
1089 inner most and any other case.
1091 Since there is always a frame to unwind from, there is always
1092 somewhere (NEXT_FRAME) to store all the info needed to construct
1093 a new (previous) frame without having to first create it. This
1094 means that the convolution below - needing to carefully order a
1095 frame's initialization - isn't needed.
1097 The irony here though, is that FRAME_CHAIN(), at least for a more
1098 up-to-date architecture, always calls FRAME_SAVED_PC(), and
1099 FRAME_SAVED_PC() computes the PC but without first needing the
1100 frame! Instead of the convolution below, we could have simply
1101 called FRAME_SAVED_PC() and been done with it! Note that
1102 FRAME_SAVED_PC() is being superseed by frame_pc_unwind() and that
1103 function does have somewhere to cache that PC value. */
1105 if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
1106 prev
->pc
= (DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf
, prev
));
1108 if (INIT_EXTRA_FRAME_INFO_P ())
1109 INIT_EXTRA_FRAME_INFO (fromleaf
, prev
);
1111 /* This entry is in the frame queue now, which is good since
1112 FRAME_SAVED_PC may use that queue to figure out its value (see
1113 tm-sparc.h). We want the pc saved in the inferior frame. */
1114 if (DEPRECATED_INIT_FRAME_PC_P ())
1115 prev
->pc
= DEPRECATED_INIT_FRAME_PC (fromleaf
, prev
);
1117 /* If ->frame and ->pc are unchanged, we are in the process of
1118 getting ourselves into an infinite backtrace. Some architectures
1119 check this in FRAME_CHAIN or thereabouts, but it seems like there
1120 is no reason this can't be an architecture-independent check. */
1121 if (prev
->frame
== next_frame
->frame
1122 && prev
->pc
== next_frame
->pc
)
1124 next_frame
->prev
= NULL
;
1125 obstack_free (&frame_cache_obstack
, prev
);
1129 /* Initialize the code used to unwind the frame PREV based on the PC
1130 (and probably other architectural information). The PC lets you
1131 check things like the debug info at that point (dwarf2cfi?) and
1132 use that to decide how the frame should be unwound. */
1133 set_unwind_by_pc (prev
->pc
, prev
->frame
, &prev
->register_unwind
,
1134 &prev
->pc_unwind
, &prev
->id_unwind
);
1136 /* NOTE: cagney/2002-11-18: The code segments, found in
1137 create_new_frame and get_prev_frame(), that initializes the
1138 frames type is subtly different. The latter only updates ->type
1139 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1140 get_prev_frame() overriding the frame's type when the INIT code
1141 has previously set it. This is really somewhat bogus. The
1142 initialization, as seen in create_new_frame(), should occur
1143 before the INIT function has been called. */
1144 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1145 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
1146 ? DEPRECATED_PC_IN_CALL_DUMMY (prev
->pc
, 0, 0)
1147 : pc_in_dummy_frame (prev
->pc
)))
1148 prev
->type
= DUMMY_FRAME
;
1151 /* FIXME: cagney/2002-11-10: This should be moved to before the
1152 INIT code above so that the INIT code knows what the frame's
1153 type is (in fact, for a [generic] dummy-frame, the type can
1154 be set and then the entire initialization can be skipped.
1155 Unforunatly, its the INIT code that sets the PC (Hmm, catch
1158 find_pc_partial_function (prev
->pc
, &name
, NULL
, NULL
);
1159 if (PC_IN_SIGTRAMP (prev
->pc
, name
))
1160 prev
->type
= SIGTRAMP_FRAME
;
1161 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1162 architectures are forcing the frame's type in INIT so we
1163 don't want to override it here. Remember, NORMAL_FRAME == 0,
1164 so it all works (just :-/). Once this initialization is
1165 moved to the start of this function, all this nastness will
1173 get_frame_pc (struct frame_info
*frame
)
1179 pc_notcurrent (struct frame_info
*frame
)
1181 /* If FRAME is not the innermost frame, that normally means that
1182 FRAME->pc points at the return instruction (which is *after* the
1183 call instruction), and we want to get the line containing the
1184 call (because the call is where the user thinks the program is).
1185 However, if the next frame is either a SIGTRAMP_FRAME or a
1186 DUMMY_FRAME, then the next frame will contain a saved interrupt
1187 PC and such a PC indicates the current (rather than next)
1188 instruction/line, consequently, for such cases, want to get the
1189 line containing fi->pc. */
1190 struct frame_info
*next
= get_next_frame (frame
);
1191 int notcurrent
= (next
!= NULL
&& get_frame_type (next
) == NORMAL_FRAME
);
1196 find_frame_sal (struct frame_info
*frame
, struct symtab_and_line
*sal
)
1198 (*sal
) = find_pc_line (frame
->pc
, pc_notcurrent (frame
));
1201 /* Per "frame.h", return the ``address'' of the frame. Code should
1202 really be using get_frame_id(). */
1204 get_frame_base (struct frame_info
*fi
)
1209 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
1210 or -1 for a NULL frame. */
1213 frame_relative_level (struct frame_info
*fi
)
1222 get_frame_type (struct frame_info
*frame
)
1224 /* Some targets still don't use [generic] dummy frames. Catch them
1226 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1227 && deprecated_frame_in_dummy (frame
))
1233 deprecated_set_frame_type (struct frame_info
*frame
, enum frame_type type
)
1235 /* Arrrg! See comment in "frame.h". */
1239 #ifdef FRAME_FIND_SAVED_REGS
1240 /* XXX - deprecated. This is a compatibility function for targets
1241 that do not yet implement FRAME_INIT_SAVED_REGS. */
1242 /* Find the addresses in which registers are saved in FRAME. */
1245 deprecated_get_frame_saved_regs (struct frame_info
*frame
,
1246 struct frame_saved_regs
*saved_regs_addr
)
1248 if (frame
->saved_regs
== NULL
)
1250 frame
->saved_regs
= (CORE_ADDR
*)
1251 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
1253 if (saved_regs_addr
== NULL
)
1255 struct frame_saved_regs saved_regs
;
1256 FRAME_FIND_SAVED_REGS (frame
, saved_regs
);
1257 memcpy (frame
->saved_regs
, &saved_regs
, SIZEOF_FRAME_SAVED_REGS
);
1261 FRAME_FIND_SAVED_REGS (frame
, *saved_regs_addr
);
1262 memcpy (frame
->saved_regs
, saved_regs_addr
, SIZEOF_FRAME_SAVED_REGS
);
1267 struct frame_extra_info
*
1268 get_frame_extra_info (struct frame_info
*fi
)
1270 return fi
->extra_info
;
1273 struct frame_extra_info
*
1274 frame_extra_info_zalloc (struct frame_info
*fi
, long size
)
1276 fi
->extra_info
= frame_obstack_zalloc (size
);
1277 return fi
->extra_info
;
1281 deprecated_update_frame_pc_hack (struct frame_info
*frame
, CORE_ADDR pc
)
1283 /* See comment in "frame.h". */
1288 deprecated_update_frame_base_hack (struct frame_info
*frame
, CORE_ADDR base
)
1290 /* See comment in "frame.h". */
1291 frame
->frame
= base
;
1295 deprecated_set_frame_saved_regs_hack (struct frame_info
*frame
,
1296 CORE_ADDR
*saved_regs
)
1298 frame
->saved_regs
= saved_regs
;
1302 deprecated_set_frame_extra_info_hack (struct frame_info
*frame
,
1303 struct frame_extra_info
*extra_info
)
1305 frame
->extra_info
= extra_info
;
1309 deprecated_set_frame_next_hack (struct frame_info
*fi
,
1310 struct frame_info
*next
)
1316 deprecated_set_frame_prev_hack (struct frame_info
*fi
,
1317 struct frame_info
*prev
)
1323 deprecated_get_frame_context (struct frame_info
*fi
)
1329 deprecated_set_frame_context (struct frame_info
*fi
,
1330 struct context
*context
)
1332 fi
->context
= context
;
1336 deprecated_frame_xmalloc (void)
1338 struct frame_info
*frame
= XMALLOC (struct frame_info
);
1339 memset (frame
, 0, sizeof (struct frame_info
));
1344 deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs
,
1345 long sizeof_extra_info
)
1347 struct frame_info
*frame
= deprecated_frame_xmalloc ();
1348 make_cleanup (xfree
, frame
);
1349 if (sizeof_saved_regs
> 0)
1351 frame
->saved_regs
= xcalloc (1, sizeof_saved_regs
);
1352 make_cleanup (xfree
, frame
->saved_regs
);
1354 if (sizeof_extra_info
> 0)
1356 frame
->extra_info
= xcalloc (1, sizeof_extra_info
);
1357 make_cleanup (xfree
, frame
->extra_info
);
1363 _initialize_frame (void)
1365 obstack_init (&frame_cache_obstack
);