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"
34 #include "sentinel-frame.h"
38 #include "frame-unwind.h"
42 /* Flag to control debugging. */
44 static int frame_debug
;
46 /* Flag to indicate whether backtraces should stop at main. */
48 static int backtrace_below_main
;
50 /* Return a frame uniq ID that can be used to, later, re-find the
54 get_frame_id (struct frame_info
*fi
)
69 const struct frame_id null_frame_id
; /* All zeros. */
72 frame_id_build (CORE_ADDR base
, CORE_ADDR func_or_pc
)
81 frame_id_p (struct frame_id l
)
83 /* The .func can be NULL but the .base cannot. */
88 frame_id_eq (struct frame_id l
, struct frame_id r
)
90 /* If .base is different, the frames are different. */
93 /* Add a test to check that the frame ID's are for the same function
99 frame_id_inner (struct frame_id l
, struct frame_id r
)
101 /* Only return non-zero when strictly inner than. Note that, per
102 comment in "frame.h", there is some fuzz here. Frameless
103 functions are not strictly inner than (same .base but different
105 return INNER_THAN (l
.base
, r
.base
);
109 frame_find_by_id (struct frame_id id
)
111 struct frame_info
*frame
;
113 /* ZERO denotes the null frame, let the caller decide what to do
114 about it. Should it instead return get_current_frame()? */
115 if (!frame_id_p (id
))
118 for (frame
= get_current_frame ();
120 frame
= get_prev_frame (frame
))
122 struct frame_id
this = get_frame_id (frame
);
123 if (frame_id_eq (id
, this))
124 /* An exact match. */
126 if (frame_id_inner (id
, this))
129 /* Either, we're not yet gone far enough out along the frame
130 chain (inner(this,id), or we're comparing frameless functions
131 (same .base, different .func, no test available). Struggle
132 on until we've definitly gone to far. */
138 frame_pc_unwind (struct frame_info
*this_frame
)
140 if (!this_frame
->pc_unwind_cache_p
)
143 if (gdbarch_unwind_pc_p (current_gdbarch
))
145 /* The right way. The `pure' way. The one true way. This
146 method depends solely on the register-unwind code to
147 determine the value of registers in THIS frame, and hence
148 the value of this frame's PC (resume address). A typical
149 implementation is no more than:
151 frame_unwind_register (this_frame, ISA_PC_REGNUM, buf);
152 return extract_address (buf, size of ISA_PC_REGNUM);
154 Note: this method is very heavily dependent on a correct
155 register-unwind implementation, it pays to fix that
156 method first; this method is frame type agnostic, since
157 it only deals with register values, it works with any
158 frame. This is all in stark contrast to the old
159 FRAME_SAVED_PC which would try to directly handle all the
160 different ways that a PC could be unwound. */
161 pc
= gdbarch_unwind_pc (current_gdbarch
, this_frame
);
163 else if (this_frame
->level
< 0)
165 /* FIXME: cagney/2003-03-06: Old code and and a sentinel
166 frame. Do like was always done. Fetch the PC's value
167 direct from the global registers array (via read_pc).
168 This assumes that this frame belongs to the current
169 global register cache. The assumption is dangerous. */
172 else if (DEPRECATED_FRAME_SAVED_PC_P ())
174 /* FIXME: cagney/2003-03-06: Old code, but not a sentinel
175 frame. Do like was always done. Note that this method,
176 unlike unwind_pc(), tries to handle all the different
177 frame cases directly. It fails. */
178 pc
= DEPRECATED_FRAME_SAVED_PC (this_frame
);
181 internal_error (__FILE__
, __LINE__
, "No gdbarch_unwind_pc method");
182 this_frame
->pc_unwind_cache
= pc
;
183 this_frame
->pc_unwind_cache_p
= 1;
185 return this_frame
->pc_unwind_cache
;
189 do_frame_unwind_register (void *src
, int regnum
, void *buf
)
191 frame_unwind_register (src
, regnum
, buf
);
196 frame_pop (struct frame_info
*this_frame
)
198 struct regcache
*scratch_regcache
;
199 struct cleanup
*cleanups
;
203 /* A legacy architecture that has implemented a custom pop
204 function. All new architectures should instead be using the
205 generic code below. */
210 /* Make a copy of all the register values unwound from this
211 frame. Save them in a scratch buffer so that there isn't a
212 race betweening trying to extract the old values from the
213 current_regcache while, at the same time writing new values
214 into that same cache. */
215 struct regcache
*scratch
= regcache_xmalloc (current_gdbarch
);
216 struct cleanup
*cleanups
= make_cleanup_regcache_xfree (scratch
);
217 regcache_save (scratch
, do_frame_unwind_register
, this_frame
);
218 /* Now copy those saved registers into the current regcache.
219 Here, regcache_cpy() calls regcache_restore(). */
220 regcache_cpy (current_regcache
, scratch
);
221 do_cleanups (cleanups
);
223 /* We've made right mess of GDB's local state, just discard
225 target_store_registers (-1);
226 flush_cached_frames ();
230 frame_register_unwind (struct frame_info
*frame
, int regnum
,
231 int *optimizedp
, enum lval_type
*lvalp
,
232 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
234 struct frame_unwind_cache
*cache
;
236 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
237 that the value proper does not need to be fetched. */
238 gdb_assert (optimizedp
!= NULL
);
239 gdb_assert (lvalp
!= NULL
);
240 gdb_assert (addrp
!= NULL
);
241 gdb_assert (realnump
!= NULL
);
242 /* gdb_assert (bufferp != NULL); */
244 /* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame
245 is broken. There is always a frame. If there, for some reason,
246 isn't, there is some pretty busted code as it should have
247 detected the problem before calling here. */
248 gdb_assert (frame
!= NULL
);
250 /* Ask this frame to unwind its register. */
251 frame
->unwind
->reg (frame
, &frame
->unwind_cache
, regnum
,
252 optimizedp
, lvalp
, addrp
, realnump
, bufferp
);
256 frame_register (struct frame_info
*frame
, int regnum
,
257 int *optimizedp
, enum lval_type
*lvalp
,
258 CORE_ADDR
*addrp
, int *realnump
, void *bufferp
)
260 /* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
261 that the value proper does not need to be fetched. */
262 gdb_assert (optimizedp
!= NULL
);
263 gdb_assert (lvalp
!= NULL
);
264 gdb_assert (addrp
!= NULL
);
265 gdb_assert (realnump
!= NULL
);
266 /* gdb_assert (bufferp != NULL); */
268 /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
269 of the register in the register cache. It should instead return
270 the REGNUM corresponding to that register. Translate the . */
271 if (GET_SAVED_REGISTER_P ())
273 GET_SAVED_REGISTER (bufferp
, optimizedp
, addrp
, frame
, regnum
, lvalp
);
274 /* Compute the REALNUM if the caller wants it. */
275 if (*lvalp
== lval_register
)
278 for (regnum
= 0; regnum
< NUM_REGS
+ NUM_PSEUDO_REGS
; regnum
++)
280 if (*addrp
== register_offset_hack (current_gdbarch
, regnum
))
286 internal_error (__FILE__
, __LINE__
,
287 "Failed to compute the register number corresponding"
288 " to 0x%s", paddr_d (*addrp
));
294 /* Obtain the register value by unwinding the register from the next
295 (more inner frame). */
296 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
297 frame_register_unwind (frame
->next
, regnum
, optimizedp
, lvalp
, addrp
,
302 frame_unwind_register (struct frame_info
*frame
, int regnum
, void *buf
)
308 frame_register_unwind (frame
, regnum
, &optimized
, &lval
, &addr
,
313 frame_unwind_signed_register (struct frame_info
*frame
, int regnum
,
316 void *buf
= alloca (MAX_REGISTER_RAW_SIZE
);
317 frame_unwind_register (frame
, regnum
, buf
);
318 (*val
) = extract_signed_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
322 frame_unwind_unsigned_register (struct frame_info
*frame
, int regnum
,
325 void *buf
= alloca (MAX_REGISTER_RAW_SIZE
);
326 frame_unwind_register (frame
, regnum
, buf
);
327 (*val
) = extract_unsigned_integer (buf
, REGISTER_VIRTUAL_SIZE (regnum
));
331 frame_read_register (struct frame_info
*frame
, int regnum
, void *buf
)
333 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
334 frame_unwind_register (frame
->next
, regnum
, buf
);
338 frame_read_unsigned_register (struct frame_info
*frame
, int regnum
,
341 /* NOTE: cagney/2002-10-31: There is a bit of dogma here - there is
342 always a frame. Both this, and the equivalent
343 frame_read_signed_register() function, can only be called with a
344 valid frame. If, for some reason, this function is called
345 without a frame then the problem isn't here, but rather in the
346 caller. It should of first created a frame and then passed that
348 /* NOTE: cagney/2002-10-31: As a side bar, keep in mind that the
349 ``current_frame'' should not be treated as a special case. While
350 ``get_next_frame (current_frame) == NULL'' currently holds, it
351 should, as far as possible, not be relied upon. In the future,
352 ``get_next_frame (current_frame)'' may instead simply return a
353 normal frame object that simply always gets register values from
354 the register cache. Consequently, frame code should try to avoid
355 tests like ``if get_next_frame() == NULL'' and instead just rely
356 on recursive frame calls (like the below code) when manipulating
358 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
359 frame_unwind_unsigned_register (frame
->next
, regnum
, val
);
363 frame_read_signed_register (struct frame_info
*frame
, int regnum
,
366 /* See note above in frame_read_unsigned_register(). */
367 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
368 frame_unwind_signed_register (frame
->next
, regnum
, val
);
372 generic_unwind_get_saved_register (char *raw_buffer
,
375 struct frame_info
*frame
,
377 enum lval_type
*lvalp
)
382 enum lval_type lvalx
;
384 if (!target_has_registers
)
385 error ("No registers.");
387 /* Keep things simple, ensure that all the pointers (except valuep)
389 if (optimizedp
== NULL
)
390 optimizedp
= &optimizedx
;
396 gdb_assert (frame
!= NULL
&& frame
->next
!= NULL
);
397 frame_register_unwind (frame
->next
, regnum
, optimizedp
, lvalp
, addrp
,
398 &realnumx
, raw_buffer
);
402 get_saved_register (char *raw_buffer
,
405 struct frame_info
*frame
,
407 enum lval_type
*lval
)
409 if (GET_SAVED_REGISTER_P ())
411 GET_SAVED_REGISTER (raw_buffer
, optimized
, addrp
, frame
, regnum
, lval
);
414 generic_unwind_get_saved_register (raw_buffer
, optimized
, addrp
, frame
,
418 /* frame_register_read ()
420 Find and return the value of REGNUM for the specified stack frame.
421 The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
423 Returns 0 if the register value could not be found. */
426 frame_register_read (struct frame_info
*frame
, int regnum
, void *myaddr
)
432 frame_register (frame
, regnum
, &optimized
, &lval
, &addr
, &realnum
, myaddr
);
434 /* FIXME: cagney/2002-05-15: This test, is just bogus.
436 It indicates that the target failed to supply a value for a
437 register because it was "not available" at this time. Problem
438 is, the target still has the register and so get saved_register()
439 may be returning a value saved on the stack. */
441 if (register_cached (regnum
) < 0)
442 return 0; /* register value not available */
448 /* Map between a frame register number and its name. A frame register
449 space is a superset of the cooked register space --- it also
450 includes builtin registers. */
453 frame_map_name_to_regnum (const char *name
, int len
)
460 /* Search register name space. */
461 for (i
= 0; i
< NUM_REGS
+ NUM_PSEUDO_REGS
; i
++)
462 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
463 && strncmp (name
, REGISTER_NAME (i
), len
) == 0)
468 /* Try builtin registers. */
469 i
= builtin_reg_map_name_to_regnum (name
, len
);
472 /* A builtin register doesn't fall into the architecture's
474 gdb_assert (i
>= NUM_REGS
+ NUM_PSEUDO_REGS
);
482 frame_map_regnum_to_name (int regnum
)
486 if (regnum
< NUM_REGS
+ NUM_PSEUDO_REGS
)
487 return REGISTER_NAME (regnum
);
488 return builtin_reg_map_regnum_to_name (regnum
);
491 /* Create a sentinel frame. */
494 create_sentinel_frame (struct regcache
*regcache
)
496 struct frame_info
*frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
497 frame
->type
= NORMAL_FRAME
;
499 /* Explicitly initialize the sentinel frame's cache. Provide it
500 with the underlying regcache. In the future additional
501 information, such as the frame's thread will be added. */
502 frame
->unwind_cache
= sentinel_frame_cache (regcache
);
503 /* For the moment there is only one sentinel frame implementation. */
504 frame
->unwind
= sentinel_frame_unwind
;
505 /* Link this frame back to itself. The frame is self referential
506 (the unwound PC is the same as the pc), so make it so. */
508 /* Always unwind the PC as part of creating this frame. This
509 ensures that the frame's PC points at something valid. */
510 /* FIXME: cagney/2003-01-10: Problem here. Unwinding a sentinel
511 frame's PC may require information such as the frame's thread's
512 stop reason. Is it possible to get to that? */
513 frame
->pc
= frame_pc_unwind (frame
);
517 /* Info about the innermost stack frame (contents of FP register) */
519 static struct frame_info
*current_frame
;
521 /* Cache for frame addresses already read by gdb. Valid only while
522 inferior is stopped. Control variables for the frame cache should
523 be local to this module. */
525 static struct obstack frame_cache_obstack
;
528 frame_obstack_zalloc (unsigned long size
)
530 void *data
= obstack_alloc (&frame_cache_obstack
, size
);
531 memset (data
, 0, size
);
536 frame_saved_regs_zalloc (struct frame_info
*fi
)
538 fi
->saved_regs
= (CORE_ADDR
*)
539 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
540 return fi
->saved_regs
;
544 get_frame_saved_regs (struct frame_info
*fi
)
546 return fi
->saved_regs
;
549 /* Return the innermost (currently executing) stack frame. This is
550 split into two functions. The function unwind_to_current_frame()
551 is wrapped in catch exceptions so that, even when the unwind of the
552 sentinel frame fails, the function still returns a stack frame. */
555 unwind_to_current_frame (struct ui_out
*ui_out
, void *args
)
557 struct frame_info
*frame
= get_prev_frame (args
);
558 /* A sentinel frame can fail to unwind, eg, because it's PC value
559 lands in somewhere like start. */
562 current_frame
= frame
;
567 get_current_frame (void)
569 /* First check, and report, the lack of registers. Having GDB
570 report "No stack!" or "No memory" when the target doesn't even
571 have registers is very confusing. Besides, "printcmd.exp"
572 explicitly checks that ``print $pc'' with no registers prints "No
574 if (!target_has_registers
)
575 error ("No registers.");
576 if (!target_has_stack
)
578 if (!target_has_memory
)
579 error ("No memory.");
580 if (current_frame
== NULL
)
582 struct frame_info
*sentinel_frame
=
583 create_sentinel_frame (current_regcache
);
584 if (catch_exceptions (uiout
, unwind_to_current_frame
, sentinel_frame
,
585 NULL
, RETURN_MASK_ERROR
) != 0)
587 /* Oops! Fake a current frame? Is this useful? It has a PC
588 of zero, for instance. */
589 current_frame
= sentinel_frame
;
592 return current_frame
;
595 /* The "selected" stack frame is used by default for local and arg
596 access. May be zero, for no selected frame. */
598 struct frame_info
*deprecated_selected_frame
;
600 /* Return the selected frame. Always non-null (unless there isn't an
601 inferior sufficient for creating a frame) in which case an error is
605 get_selected_frame (void)
607 if (deprecated_selected_frame
== NULL
)
608 /* Hey! Don't trust this. It should really be re-finding the
609 last selected frame of the currently selected thread. This,
610 though, is better than nothing. */
611 select_frame (get_current_frame ());
612 /* There is always a frame. */
613 gdb_assert (deprecated_selected_frame
!= NULL
);
614 return deprecated_selected_frame
;
617 /* Select frame FI (or NULL - to invalidate the current frame). */
620 select_frame (struct frame_info
*fi
)
622 register struct symtab
*s
;
624 deprecated_selected_frame
= fi
;
625 /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
626 frame is being invalidated. */
627 if (selected_frame_level_changed_hook
)
628 selected_frame_level_changed_hook (frame_relative_level (fi
));
630 /* FIXME: kseitz/2002-08-28: It would be nice to call
631 selected_frame_level_changed_event right here, but due to limitations
632 in the current interfaces, we would end up flooding UIs with events
633 because select_frame is used extensively internally.
635 Once we have frame-parameterized frame (and frame-related) commands,
636 the event notification can be moved here, since this function will only
637 be called when the users selected frame is being changed. */
639 /* Ensure that symbols for this frame are read in. Also, determine the
640 source language of this frame, and switch to it if desired. */
643 s
= find_pc_symtab (fi
->pc
);
645 && s
->language
!= current_language
->la_language
646 && s
->language
!= language_unknown
647 && language_mode
== language_mode_auto
)
649 set_language (s
->language
);
654 /* Return the register saved in the simplistic ``saved_regs'' cache.
655 If the value isn't here AND a value is needed, try the next inner
659 frame_saved_regs_register_unwind (struct frame_info
*frame
, void **cache
,
660 int regnum
, int *optimizedp
,
661 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
662 int *realnump
, void *bufferp
)
664 /* There is always a frame at this point. And THIS is the frame
665 we're interested in. */
666 gdb_assert (frame
!= NULL
);
667 /* If we're using generic dummy frames, we'd better not be in a call
668 dummy. (generic_call_dummy_register_unwind ought to have been called
670 gdb_assert (!(DEPRECATED_USE_GENERIC_DUMMY_FRAMES
671 && (get_frame_type (frame
) == DUMMY_FRAME
)));
673 /* Only (older) architectures that implement the
674 DEPRECATED_FRAME_INIT_SAVED_REGS method should be using this
676 gdb_assert (DEPRECATED_FRAME_INIT_SAVED_REGS_P ());
678 /* Load the saved_regs register cache. */
679 if (get_frame_saved_regs (frame
) == NULL
)
680 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
682 if (get_frame_saved_regs (frame
) != NULL
683 && get_frame_saved_regs (frame
)[regnum
] != 0)
685 if (regnum
== SP_REGNUM
)
687 /* SP register treated specially. */
693 store_address (bufferp
, REGISTER_RAW_SIZE (regnum
),
694 get_frame_saved_regs (frame
)[regnum
]);
698 /* Any other register is saved in memory, fetch it but cache
699 a local copy of its value. */
701 *lvalp
= lval_memory
;
702 *addrp
= get_frame_saved_regs (frame
)[regnum
];
707 /* Save each register value, as it is read in, in a
708 frame based cache. */
709 void **regs
= (*cache
);
712 int sizeof_cache
= ((NUM_REGS
+ NUM_PSEUDO_REGS
)
714 regs
= frame_obstack_zalloc (sizeof_cache
);
717 if (regs
[regnum
] == NULL
)
720 = frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum
));
721 read_memory (get_frame_saved_regs (frame
)[regnum
], regs
[regnum
],
722 REGISTER_RAW_SIZE (regnum
));
724 memcpy (bufferp
, regs
[regnum
], REGISTER_RAW_SIZE (regnum
));
726 /* Read the value in from memory. */
727 read_memory (get_frame_saved_regs (frame
)[regnum
], bufferp
,
728 REGISTER_RAW_SIZE (regnum
));
735 /* No luck, assume this and the next frame have the same register
736 value. Pass the request down the frame chain to the next frame.
737 Hopefully that will find the register's location, either in a
738 register or in memory. */
739 frame_register (frame
, regnum
, optimizedp
, lvalp
, addrp
, realnump
,
744 frame_saved_regs_id_unwind (struct frame_info
*next_frame
, void **cache
,
751 /* Start out by assuming it's NULL. */
752 (*id
) = null_frame_id
;
754 if (frame_relative_level (next_frame
) <= 0)
755 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
756 the frame chain, not just the inner most frame! The generic,
757 per-architecture, frame code should handle this and the below
758 should simply be removed. */
759 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (next_frame
);
764 /* A frameless inner-most frame. The `FP' (which isn't an
765 architecture frame-pointer register!) of the caller is the same
767 /* FIXME: 2002-11-09: There isn't any reason to special case this
768 edge condition. Instead the per-architecture code should hande
770 base
= get_frame_base (next_frame
);
773 /* Two macros defined in tm.h specify the machine-dependent
774 actions to be performed here.
776 First, get the frame's chain-pointer.
778 If that is zero, the frame is the outermost frame or a leaf
779 called by the outermost frame. This means that if start
780 calls main without a frame, we'll return 0 (which is fine
783 Nope; there's a problem. This also returns when the current
784 routine is a leaf of main. This is unacceptable. We move
785 this to after the ffi test; I'd rather have backtraces from
786 start go curfluy than have an abort called from main not show
788 gdb_assert (FRAME_CHAIN_P ());
789 base
= FRAME_CHAIN (next_frame
);
791 if (!frame_chain_valid (base
, next_frame
))
797 /* FIXME: cagney/2002-06-08: This should probably return the frame's
798 function and not the PC (a.k.a. resume address). */
799 pc
= frame_pc_unwind (next_frame
);
804 const struct frame_unwind trad_frame_unwinder
= {
805 frame_saved_regs_id_unwind
,
806 frame_saved_regs_register_unwind
808 const struct frame_unwind
*trad_frame_unwind
= &trad_frame_unwinder
;
811 /* Function: get_saved_register
812 Find register number REGNUM relative to FRAME and put its (raw,
813 target format) contents in *RAW_BUFFER.
815 Set *OPTIMIZED if the variable was optimized out (and thus can't be
816 fetched). Note that this is never set to anything other than zero
817 in this implementation.
819 Set *LVAL to lval_memory, lval_register, or not_lval, depending on
820 whether the value was fetched from memory, from a register, or in a
821 strange and non-modifiable way (e.g. a frame pointer which was
822 calculated rather than fetched). We will use not_lval for values
823 fetched from generic dummy frames.
825 Set *ADDRP to the address, either in memory or as a REGISTER_BYTE
826 offset into the registers array. If the value is stored in a dummy
827 frame, set *ADDRP to zero.
829 To use this implementation, define a function called
830 "get_saved_register" in your target code, which simply passes all
831 of its arguments to this function.
833 The argument RAW_BUFFER must point to aligned memory. */
836 deprecated_generic_get_saved_register (char *raw_buffer
, int *optimized
,
838 struct frame_info
*frame
, int regnum
,
839 enum lval_type
*lval
)
841 if (!target_has_registers
)
842 error ("No registers.");
844 gdb_assert (DEPRECATED_FRAME_INIT_SAVED_REGS_P ());
846 /* Normal systems don't optimize out things with register numbers. */
847 if (optimized
!= NULL
)
850 if (addrp
) /* default assumption: not found in memory */
853 /* Note: since the current frame's registers could only have been
854 saved by frames INTERIOR TO the current frame, we skip examining
855 the current frame itself: otherwise, we would be getting the
856 previous frame's registers which were saved by the current frame. */
860 for (frame
= get_next_frame (frame
);
861 frame_relative_level (frame
) >= 0;
862 frame
= get_next_frame (frame
))
864 if (get_frame_type (frame
) == DUMMY_FRAME
)
866 if (lval
) /* found it in a CALL_DUMMY frame */
869 /* FIXME: cagney/2002-06-26: This should be via the
870 gdbarch_register_read() method so that it, on the
871 fly, constructs either a raw or pseudo register
872 from the raw register cache. */
874 (generic_find_dummy_frame (get_frame_pc (frame
),
875 get_frame_base (frame
)),
880 DEPRECATED_FRAME_INIT_SAVED_REGS (frame
);
881 if (get_frame_saved_regs (frame
) != NULL
882 && get_frame_saved_regs (frame
)[regnum
] != 0)
884 if (lval
) /* found it saved on the stack */
886 if (regnum
== SP_REGNUM
)
888 if (raw_buffer
) /* SP register treated specially */
889 store_address (raw_buffer
, REGISTER_RAW_SIZE (regnum
),
890 get_frame_saved_regs (frame
)[regnum
]);
894 if (addrp
) /* any other register */
895 *addrp
= get_frame_saved_regs (frame
)[regnum
];
897 read_memory (get_frame_saved_regs (frame
)[regnum
], raw_buffer
,
898 REGISTER_RAW_SIZE (regnum
));
905 /* If we get thru the loop to this point, it means the register was
906 not saved in any frame. Return the actual live-register value. */
908 if (lval
) /* found it in a live register */
909 *lval
= lval_register
;
911 *addrp
= REGISTER_BYTE (regnum
);
913 deprecated_read_register_gen (regnum
, raw_buffer
);
916 /* Determine the frame's type based on its PC. */
918 static enum frame_type
919 frame_type_from_pc (CORE_ADDR pc
)
921 /* FIXME: cagney/2002-11-24: Can't yet directly call
922 pc_in_dummy_frame() as some architectures don't set
923 PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the
924 latter is implemented by simply calling pc_in_dummy_frame). */
925 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
926 && DEPRECATED_PC_IN_CALL_DUMMY (pc
, 0, 0))
931 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
932 if (PC_IN_SIGTRAMP (pc
, name
))
933 return SIGTRAMP_FRAME
;
939 /* Create an arbitrary (i.e. address specified by user) or innermost frame.
940 Always returns a non-NULL value. */
943 create_new_frame (CORE_ADDR addr
, CORE_ADDR pc
)
945 struct frame_info
*fi
;
947 fi
= frame_obstack_zalloc (sizeof (struct frame_info
));
951 fi
->next
= create_sentinel_frame (current_regcache
);
952 fi
->type
= frame_type_from_pc (pc
);
954 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
955 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, fi
);
957 /* Select/initialize an unwind function. */
958 fi
->unwind
= frame_unwind_find_by_pc (current_gdbarch
, fi
->pc
);
963 /* Return the frame that FRAME calls (NULL if FRAME is the innermost
964 frame). Be careful to not fall off the bottom of the frame chain
965 and onto the sentinel frame. */
968 get_next_frame (struct frame_info
*frame
)
970 if (frame
->level
> 0)
976 /* Flush the entire frame cache. */
979 flush_cached_frames (void)
981 /* Since we can't really be sure what the first object allocated was */
982 obstack_free (&frame_cache_obstack
, 0);
983 obstack_init (&frame_cache_obstack
);
985 current_frame
= NULL
; /* Invalidate cache */
987 annotate_frames_invalid ();
990 /* Flush the frame cache, and start a new one if necessary. */
993 reinit_frame_cache (void)
995 flush_cached_frames ();
997 /* FIXME: The inferior_ptid test is wrong if there is a corefile. */
998 if (PIDGET (inferior_ptid
) != 0)
1000 select_frame (get_current_frame ());
1004 /* Create the previous frame using the deprecated methods
1005 INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */
1007 static struct frame_info
*
1008 legacy_get_prev_frame (struct frame_info
*next_frame
)
1010 CORE_ADDR address
= 0;
1011 struct frame_info
*prev
;
1014 /* This code only works on normal frames. A sentinel frame, where
1015 the level is -1, should never reach this code. */
1016 gdb_assert (next_frame
->level
>= 0);
1018 /* On some machines it is possible to call a function without
1019 setting up a stack frame for it. On these machines, we
1020 define this macro to take two args; a frameinfo pointer
1021 identifying a frame and a variable to set or clear if it is
1022 or isn't leafless. */
1024 /* Still don't want to worry about this except on the innermost
1025 frame. This macro will set FROMLEAF if NEXT_FRAME is a frameless
1026 function invocation. */
1027 if (next_frame
->level
== 0)
1028 /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
1029 the frame chain, not just the inner most frame! The generic,
1030 per-architecture, frame code should handle this and the below
1031 should simply be removed. */
1032 fromleaf
= FRAMELESS_FUNCTION_INVOCATION (next_frame
);
1037 /* A frameless inner-most frame. The `FP' (which isn't an
1038 architecture frame-pointer register!) of the caller is the same
1040 /* FIXME: 2002-11-09: There isn't any reason to special case this
1041 edge condition. Instead the per-architecture code should hande
1043 address
= get_frame_base (next_frame
);
1046 /* Two macros defined in tm.h specify the machine-dependent
1047 actions to be performed here.
1049 First, get the frame's chain-pointer.
1051 If that is zero, the frame is the outermost frame or a leaf
1052 called by the outermost frame. This means that if start
1053 calls main without a frame, we'll return 0 (which is fine
1056 Nope; there's a problem. This also returns when the current
1057 routine is a leaf of main. This is unacceptable. We move
1058 this to after the ffi test; I'd rather have backtraces from
1059 start go curfluy than have an abort called from main not show
1061 gdb_assert (FRAME_CHAIN_P ());
1062 address
= FRAME_CHAIN (next_frame
);
1064 if (!frame_chain_valid (address
, next_frame
))
1070 /* Create an initially zero previous frame. */
1071 prev
= frame_obstack_zalloc (sizeof (struct frame_info
));
1074 next_frame
->prev
= prev
;
1075 prev
->next
= next_frame
;
1076 prev
->frame
= address
;
1077 prev
->level
= next_frame
->level
+ 1;
1078 /* FIXME: cagney/2002-11-18: Should be setting the frame's type
1079 here, before anything else, and not last. Various INIT functions
1080 are full of work-arounds for the frames type not being set
1081 correctly from the word go. Ulgh! */
1082 prev
->type
= NORMAL_FRAME
;
1084 /* This change should not be needed, FIXME! We should determine
1085 whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
1086 after DEPRECATED_INIT_EXTRA_FRAME_INFO and come up with a simple
1087 way to express what goes on here.
1089 DEPRECATED_INIT_EXTRA_FRAME_INFO is called from two places:
1090 create_new_frame (where the PC is already set up) and here (where
1091 it isn't). DEPRECATED_INIT_FRAME_PC is only called from here,
1092 always after DEPRECATED_INIT_EXTRA_FRAME_INFO.
1094 The catch is the MIPS, where DEPRECATED_INIT_EXTRA_FRAME_INFO
1095 requires the PC value (which hasn't been set yet). Some other
1096 machines appear to require DEPRECATED_INIT_EXTRA_FRAME_INFO
1097 before they can do DEPRECATED_INIT_FRAME_PC. Phoo.
1099 We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
1100 complication to an already overcomplicated part of GDB.
1101 gnu@cygnus.com, 15Sep92.
1103 Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
1104 DEPRECATED_INIT_EXTRA_FRAME_INFO, one possible scheme:
1106 SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
1107 (read_fp ()), read_pc ()). Machines with extra frame info would
1108 do that (or the local equivalent) and then set the extra fields.
1110 SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
1111 create_new_frame would no longer init extra frame info;
1112 SETUP_ARBITRARY_FRAME would have to do that.
1114 INIT_PREV_FRAME(fromleaf, prev) Replace
1115 DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC.
1116 This should also return a flag saying whether to keep the new
1117 frame, or whether to discard it, because on some machines (e.g.
1118 mips) it is really awkward to have FRAME_CHAIN_VALID called
1119 BEFORE DEPRECATED_INIT_EXTRA_FRAME_INFO (there is no good way to
1120 get information deduced in FRAME_CHAIN_VALID into the extra
1121 fields of the new frame). std_frame_pc(fromleaf, prev)
1123 This is the default setting for INIT_PREV_FRAME. It just does
1124 what the default DEPRECATED_INIT_FRAME_PC does. Some machines
1125 will call it from INIT_PREV_FRAME (either at the beginning, the
1126 end, or in the middle). Some machines won't use it.
1128 kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
1130 /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
1131 reason for things to be this complicated.
1133 The trick is to assume that there is always a frame. Instead of
1134 special casing the inner-most frame, create fake frame
1135 (containing the hardware registers) that is inner to the
1136 user-visible inner-most frame (...) and then unwind from that.
1137 That way architecture code can use use the standard
1138 frame_XX_unwind() functions and not differentiate between the
1139 inner most and any other case.
1141 Since there is always a frame to unwind from, there is always
1142 somewhere (NEXT_FRAME) to store all the info needed to construct
1143 a new (previous) frame without having to first create it. This
1144 means that the convolution below - needing to carefully order a
1145 frame's initialization - isn't needed.
1147 The irony here though, is that FRAME_CHAIN(), at least for a more
1148 up-to-date architecture, always calls FRAME_SAVED_PC(), and
1149 FRAME_SAVED_PC() computes the PC but without first needing the
1150 frame! Instead of the convolution below, we could have simply
1151 called FRAME_SAVED_PC() and been done with it! Note that
1152 FRAME_SAVED_PC() is being superseed by frame_pc_unwind() and that
1153 function does have somewhere to cache that PC value. */
1155 if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
1156 prev
->pc
= (DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf
, prev
));
1158 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1159 DEPRECATED_INIT_EXTRA_FRAME_INFO (fromleaf
, prev
);
1161 /* This entry is in the frame queue now, which is good since
1162 FRAME_SAVED_PC may use that queue to figure out its value (see
1163 tm-sparc.h). We want the pc saved in the inferior frame. */
1164 if (DEPRECATED_INIT_FRAME_PC_P ())
1165 prev
->pc
= DEPRECATED_INIT_FRAME_PC (fromleaf
, prev
);
1167 /* If ->frame and ->pc are unchanged, we are in the process of
1168 getting ourselves into an infinite backtrace. Some architectures
1169 check this in FRAME_CHAIN or thereabouts, but it seems like there
1170 is no reason this can't be an architecture-independent check. */
1171 if (prev
->frame
== next_frame
->frame
1172 && prev
->pc
== next_frame
->pc
)
1174 next_frame
->prev
= NULL
;
1175 obstack_free (&frame_cache_obstack
, prev
);
1179 /* Initialize the code used to unwind the frame PREV based on the PC
1180 (and probably other architectural information). The PC lets you
1181 check things like the debug info at that point (dwarf2cfi?) and
1182 use that to decide how the frame should be unwound. */
1183 prev
->unwind
= frame_unwind_find_by_pc (current_gdbarch
, prev
->pc
);
1185 /* NOTE: cagney/2002-11-18: The code segments, found in
1186 create_new_frame and get_prev_frame(), that initializes the
1187 frames type is subtly different. The latter only updates ->type
1188 when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
1189 get_prev_frame() overriding the frame's type when the INIT code
1190 has previously set it. This is really somewhat bogus. The
1191 initialization, as seen in create_new_frame(), should occur
1192 before the INIT function has been called. */
1193 if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1194 && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
1195 ? DEPRECATED_PC_IN_CALL_DUMMY (prev
->pc
, 0, 0)
1196 : pc_in_dummy_frame (prev
->pc
)))
1197 prev
->type
= DUMMY_FRAME
;
1200 /* FIXME: cagney/2002-11-10: This should be moved to before the
1201 INIT code above so that the INIT code knows what the frame's
1202 type is (in fact, for a [generic] dummy-frame, the type can
1203 be set and then the entire initialization can be skipped.
1204 Unforunatly, its the INIT code that sets the PC (Hmm, catch
1207 find_pc_partial_function (prev
->pc
, &name
, NULL
, NULL
);
1208 if (PC_IN_SIGTRAMP (prev
->pc
, name
))
1209 prev
->type
= SIGTRAMP_FRAME
;
1210 /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
1211 architectures are forcing the frame's type in INIT so we
1212 don't want to override it here. Remember, NORMAL_FRAME == 0,
1213 so it all works (just :-/). Once this initialization is
1214 moved to the start of this function, all this nastness will
1221 /* Return a structure containing various interesting information
1222 about the frame that called NEXT_FRAME. Returns NULL
1223 if there is no such frame. */
1226 get_prev_frame (struct frame_info
*next_frame
)
1228 struct frame_info
*prev_frame
;
1230 /* Return the inner-most frame, when the caller passes in NULL. */
1231 /* NOTE: cagney/2002-11-09: Not sure how this would happen. The
1232 caller should have previously obtained a valid frame using
1233 get_selected_frame() and then called this code - only possibility
1234 I can think of is code behaving badly.
1236 NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
1237 block_innermost_frame(). It does the sequence: frame = NULL;
1238 while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
1239 it couldn't be written better, I don't know.
1241 NOTE: cagney/2003-01-11: I suspect what is happening is
1242 block_innermost_frame() is, when the target has no state
1243 (registers, memory, ...), still calling this function. The
1244 assumption being that this function will return NULL indicating
1245 that a frame isn't possible, rather than checking that the target
1246 has state and then calling get_current_frame() and
1247 get_prev_frame(). This is a guess mind. */
1248 if (next_frame
== NULL
)
1250 /* NOTE: cagney/2002-11-09: There was a code segment here that
1251 would error out when CURRENT_FRAME was NULL. The comment
1252 that went with it made the claim ...
1254 ``This screws value_of_variable, which just wants a nice
1255 clean NULL return from block_innermost_frame if there are no
1256 frames. I don't think I've ever seen this message happen
1257 otherwise. And returning NULL here is a perfectly legitimate
1260 Per the above, this code shouldn't even be called with a NULL
1262 return current_frame
;
1265 /* There is always a frame. If this assertion fails, suspect that
1266 something should be calling get_selected_frame() or
1267 get_current_frame(). */
1268 gdb_assert (next_frame
!= NULL
);
1270 if (next_frame
->level
>= 0
1271 && !backtrace_below_main
1272 && inside_main_func (get_frame_pc (next_frame
)))
1273 /* Don't unwind past main(), bug always unwind the sentinel frame.
1274 Note, this is done _before_ the frame has been marked as
1275 previously unwound. That way if the user later decides to
1276 allow unwinds past main(), that just happens. */
1279 fprintf_unfiltered (gdb_stdlog
,
1280 "Outermost frame - inside main func.\n");
1284 /* Only try to do the unwind once. */
1285 if (next_frame
->prev_p
)
1286 return next_frame
->prev
;
1287 next_frame
->prev_p
= 1;
1289 /* If we're inside the entry file, it isn't valid. Don't apply this
1290 test to a dummy frame - dummy frame PC's typically land in the
1291 entry file. Don't apply this test to the sentinel frame.
1292 Sentinel frames should always be allowed to unwind. */
1293 /* NOTE: drow/2002-12-25: should there be a way to disable this
1294 check? It assumes a single small entry file, and the way some
1295 debug readers (e.g. dbxread) figure out which object is the
1296 entry file is somewhat hokey. */
1297 /* NOTE: cagney/2003-01-10: If there is a way of disabling this test
1298 then it should probably be moved to before the ->prev_p test,
1300 if (next_frame
->type
!= DUMMY_FRAME
&& next_frame
->level
>= 0
1301 && inside_entry_file (get_frame_pc (next_frame
)))
1304 fprintf_unfiltered (gdb_stdlog
,
1305 "Outermost frame - inside entry file\n");
1309 /* If we're already inside the entry function for the main objfile,
1310 then it isn't valid. Don't apply this test to a dummy frame -
1311 dummy frame PC's typically land in the entry func. Don't apply
1312 this test to the sentinel frame. Sentinel frames should always
1313 be allowed to unwind. */
1314 /* NOTE: cagney/2003-02-25: Don't enable until someone has found
1315 hard evidence that this is needed. */
1317 && next_frame
->type
!= DUMMY_FRAME
&& next_frame
->level
>= 0
1318 && inside_entry_func (get_frame_pc (next_frame
)))
1321 fprintf_unfiltered (gdb_stdlog
,
1322 "Outermost frame - inside entry func\n");
1326 /* If any of the old frame initialization methods are around, use
1327 the legacy get_prev_frame method. Just don't try to unwind a
1328 sentinel frame using that method - it doesn't work. All sentinal
1329 frames use the new unwind code. */
1330 if ((DEPRECATED_INIT_FRAME_PC_P ()
1331 || DEPRECATED_INIT_FRAME_PC_FIRST_P ()
1332 || DEPRECATED_INIT_EXTRA_FRAME_INFO_P ()
1333 || FRAME_CHAIN_P ())
1334 && next_frame
->level
>= 0)
1336 prev_frame
= legacy_get_prev_frame (next_frame
);
1337 if (frame_debug
&& prev_frame
== NULL
)
1338 fprintf_unfiltered (gdb_stdlog
,
1339 "Outermost frame - legacy_get_prev_frame NULL.\n");
1343 /* Allocate the new frame but do not wire it in to the frame chain.
1344 Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
1345 frame->next to pull some fancy tricks (of course such code is, by
1346 definition, recursive). Try to prevent it.
1348 There is no reason to worry about memory leaks, should the
1349 remainder of the function fail. The allocated memory will be
1350 quickly reclaimed when the frame cache is flushed, and the `we've
1351 been here before' check above will stop repeated memory
1352 allocation calls. */
1353 prev_frame
= FRAME_OBSTACK_ZALLOC (struct frame_info
);
1354 prev_frame
->level
= next_frame
->level
+ 1;
1356 /* Try to unwind the PC. If that doesn't work, assume we've reached
1357 the oldest frame and simply return. Is there a better sentinal
1358 value? The unwound PC value is then used to initialize the new
1359 previous frame's type.
1361 Note that the pc-unwind is intentionally performed before the
1362 frame chain. This is ok since, for old targets, both
1363 frame_pc_unwind (nee, FRAME_SAVED_PC) and FRAME_CHAIN()) assume
1364 NEXT_FRAME's data structures have already been initialized (using
1365 DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
1368 By unwinding the PC first, it becomes possible to, in the case of
1369 a dummy frame, avoid also unwinding the frame ID. This is
1370 because (well ignoring the PPC) a dummy frame can be located
1371 using NEXT_FRAME's frame ID. */
1373 prev_frame
->pc
= frame_pc_unwind (next_frame
);
1374 if (prev_frame
->pc
== 0)
1376 /* The allocated PREV_FRAME will be reclaimed when the frame
1377 obstack is next purged. */
1379 fprintf_unfiltered (gdb_stdlog
,
1380 "Outermost frame - unwound PC zero\n");
1383 prev_frame
->type
= frame_type_from_pc (prev_frame
->pc
);
1385 /* Set the unwind functions based on that identified PC. */
1386 prev_frame
->unwind
= frame_unwind_find_by_pc (current_gdbarch
,
1389 /* Find the prev's frame's ID. */
1390 switch (prev_frame
->type
)
1393 /* When unwinding a normal frame, the stack structure is
1394 determined by analyzing the frame's function's code (be it
1395 using brute force prologue analysis, or the dwarf2 CFI). In
1396 the case of a dummy frame, that simply isn't possible. The
1397 The PC is either the program entry point, or some random
1398 address on the stack. Trying to use that PC to apply
1399 standard frame ID unwind techniques is just asking for
1401 if (gdbarch_unwind_dummy_id_p (current_gdbarch
))
1403 /* Assume hand_function_call(), via SAVE_DUMMY_FRAME_TOS,
1404 previously saved the dummy frame's ID. Things only work
1405 if the two return the same value. */
1406 gdb_assert (SAVE_DUMMY_FRAME_TOS_P ());
1407 /* Use an architecture specific method to extract the prev's
1408 dummy ID from the next frame. Note that this method uses
1409 frame_register_unwind to obtain the register values
1410 needed to determine the dummy frame's ID. */
1411 prev_frame
->id
= gdbarch_unwind_dummy_id (current_gdbarch
,
1414 else if (next_frame
->level
< 0)
1416 /* We're unwinding a sentinel frame, the PC of which is
1417 pointing at a stack dummy. Fake up the dummy frame's ID
1418 using the same sequence as is found a traditional
1419 unwinder. Once all architectures supply the
1420 unwind_dummy_id method, this code can go away. */
1421 prev_frame
->id
.base
= read_fp ();
1422 prev_frame
->id
.pc
= read_pc ();
1426 /* Outch! We're not on the innermost frame yet we're trying
1427 to unwind to a dummy. The architecture must provide the
1428 unwind_dummy_id() method. Abandon the unwind process but
1429 only after first warning the user. */
1430 internal_warning (__FILE__
, __LINE__
,
1431 "Missing unwind_dummy_id architecture method");
1436 case SIGTRAMP_FRAME
:
1437 /* FIXME: cagney/2003-03-04: The below call isn't right. It
1438 should instead be doing something like "prev_frame -> unwind
1439 -> id (next_frame, & prev_frame -> unwind_cache, & prev_frame
1440 -> id)" but that requires more extensive (pending) changes. */
1441 next_frame
->unwind
->id (next_frame
, &next_frame
->unwind_cache
,
1443 /* Check that the unwound ID is valid. */
1444 if (!frame_id_p (prev_frame
->id
))
1447 fprintf_unfiltered (gdb_stdlog
,
1448 "Outermost frame - unwound frame ID invalid\n");
1451 /* Check that the new frame isn't inner to (younger, below,
1452 next) the old frame. If that happens the frame unwind is
1454 /* FIXME: cagney/2003-02-25: Ignore the sentinel frame since
1455 that doesn't have a valid frame ID. Should instead set the
1456 sentinel frame's frame ID to a `sentinel'. Leave it until
1457 after the switch to storing the frame ID, instead of the
1458 frame base, in the frame object. */
1459 if (next_frame
->level
>= 0
1460 && frame_id_inner (prev_frame
->id
, get_frame_id (next_frame
)))
1461 error ("Unwound frame inner-to selected frame (corrupt stack?)");
1462 /* Note that, due to frameless functions, the stronger test of
1463 the new frame being outer to the old frame can't be used -
1464 frameless functions differ by only their PC value. */
1467 internal_error (__FILE__
, __LINE__
, "bad switch");
1470 /* FIXME: cagney/2002-12-18: Instead of this hack, should only store
1471 the frame ID in PREV_FRAME. Unfortunatly, some architectures
1472 (HP/UX) still reply on EXTRA_FRAME_INFO and, hence, still poke at
1473 the "struct frame_info" object directly. */
1474 prev_frame
->frame
= prev_frame
->id
.base
;
1477 next_frame
->prev
= prev_frame
;
1478 prev_frame
->next
= next_frame
;
1480 /* FIXME: cagney/2002-01-19: This call will go away. Instead of
1481 initializing extra info, all frames will use the frame_cache
1482 (passed to the unwind functions) to store additional frame info.
1483 Unfortunatly legacy targets can't use legacy_get_prev_frame() to
1484 unwind the sentinel frame and, consequently, are forced to take
1485 this code path and rely on the below call to
1486 DEPRECATED_INIT_EXTRA_FRAME_INFO to initialize the inner-most
1488 if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
1490 gdb_assert (prev_frame
->level
== 0);
1491 DEPRECATED_INIT_EXTRA_FRAME_INFO (0, prev_frame
);
1498 get_frame_pc (struct frame_info
*frame
)
1504 pc_notcurrent (struct frame_info
*frame
)
1506 /* If FRAME is not the innermost frame, that normally means that
1507 FRAME->pc points at the return instruction (which is *after* the
1508 call instruction), and we want to get the line containing the
1509 call (because the call is where the user thinks the program is).
1510 However, if the next frame is either a SIGTRAMP_FRAME or a
1511 DUMMY_FRAME, then the next frame will contain a saved interrupt
1512 PC and such a PC indicates the current (rather than next)
1513 instruction/line, consequently, for such cases, want to get the
1514 line containing fi->pc. */
1515 struct frame_info
*next
= get_next_frame (frame
);
1516 int notcurrent
= (next
!= NULL
&& get_frame_type (next
) == NORMAL_FRAME
);
1521 find_frame_sal (struct frame_info
*frame
, struct symtab_and_line
*sal
)
1523 (*sal
) = find_pc_line (frame
->pc
, pc_notcurrent (frame
));
1526 /* Per "frame.h", return the ``address'' of the frame. Code should
1527 really be using get_frame_id(). */
1529 get_frame_base (struct frame_info
*fi
)
1534 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
1535 or -1 for a NULL frame. */
1538 frame_relative_level (struct frame_info
*fi
)
1547 get_frame_type (struct frame_info
*frame
)
1549 /* Some targets still don't use [generic] dummy frames. Catch them
1551 if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
1552 && deprecated_frame_in_dummy (frame
))
1558 deprecated_set_frame_type (struct frame_info
*frame
, enum frame_type type
)
1560 /* Arrrg! See comment in "frame.h". */
1564 #ifdef FRAME_FIND_SAVED_REGS
1565 /* XXX - deprecated. This is a compatibility function for targets
1566 that do not yet implement DEPRECATED_FRAME_INIT_SAVED_REGS. */
1567 /* Find the addresses in which registers are saved in FRAME. */
1570 deprecated_get_frame_saved_regs (struct frame_info
*frame
,
1571 struct frame_saved_regs
*saved_regs_addr
)
1573 if (frame
->saved_regs
== NULL
)
1575 frame
->saved_regs
= (CORE_ADDR
*)
1576 frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS
);
1578 if (saved_regs_addr
== NULL
)
1580 struct frame_saved_regs saved_regs
;
1581 FRAME_FIND_SAVED_REGS (frame
, saved_regs
);
1582 memcpy (frame
->saved_regs
, &saved_regs
, SIZEOF_FRAME_SAVED_REGS
);
1586 FRAME_FIND_SAVED_REGS (frame
, *saved_regs_addr
);
1587 memcpy (frame
->saved_regs
, saved_regs_addr
, SIZEOF_FRAME_SAVED_REGS
);
1592 struct frame_extra_info
*
1593 get_frame_extra_info (struct frame_info
*fi
)
1595 return fi
->extra_info
;
1598 struct frame_extra_info
*
1599 frame_extra_info_zalloc (struct frame_info
*fi
, long size
)
1601 fi
->extra_info
= frame_obstack_zalloc (size
);
1602 return fi
->extra_info
;
1606 deprecated_update_frame_pc_hack (struct frame_info
*frame
, CORE_ADDR pc
)
1608 /* See comment in "frame.h". */
1610 /* NOTE: cagney/2003-03-11: Some architectures (e.g., Arm) are
1611 maintaining a locally allocated frame object. Since such frame's
1612 are not in the frame chain, it isn't possible to assume that the
1613 frame has a next. Sigh. */
1614 if (frame
->next
!= NULL
)
1616 /* While we're at it, update this frame's cached PC value, found
1617 in the next frame. Oh for the day when "struct frame_info"
1618 is opaque and this hack on hack can just go away. */
1619 frame
->next
->pc_unwind_cache
= pc
;
1620 frame
->next
->pc_unwind_cache_p
= 1;
1625 deprecated_update_frame_base_hack (struct frame_info
*frame
, CORE_ADDR base
)
1627 /* See comment in "frame.h". */
1628 frame
->frame
= base
;
1632 deprecated_set_frame_saved_regs_hack (struct frame_info
*frame
,
1633 CORE_ADDR
*saved_regs
)
1635 frame
->saved_regs
= saved_regs
;
1639 deprecated_set_frame_extra_info_hack (struct frame_info
*frame
,
1640 struct frame_extra_info
*extra_info
)
1642 frame
->extra_info
= extra_info
;
1646 deprecated_set_frame_next_hack (struct frame_info
*fi
,
1647 struct frame_info
*next
)
1653 deprecated_set_frame_prev_hack (struct frame_info
*fi
,
1654 struct frame_info
*prev
)
1660 deprecated_get_frame_context (struct frame_info
*fi
)
1666 deprecated_set_frame_context (struct frame_info
*fi
,
1667 struct context
*context
)
1669 fi
->context
= context
;
1673 deprecated_frame_xmalloc (void)
1675 struct frame_info
*frame
= XMALLOC (struct frame_info
);
1676 memset (frame
, 0, sizeof (struct frame_info
));
1681 deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs
,
1682 long sizeof_extra_info
)
1684 struct frame_info
*frame
= deprecated_frame_xmalloc ();
1685 make_cleanup (xfree
, frame
);
1686 if (sizeof_saved_regs
> 0)
1688 frame
->saved_regs
= xcalloc (1, sizeof_saved_regs
);
1689 make_cleanup (xfree
, frame
->saved_regs
);
1691 if (sizeof_extra_info
> 0)
1693 frame
->extra_info
= xcalloc (1, sizeof_extra_info
);
1694 make_cleanup (xfree
, frame
->extra_info
);
1700 _initialize_frame (void)
1702 obstack_init (&frame_cache_obstack
);
1704 /* FIXME: cagney/2003-01-19: This command needs a rename. Suggest
1705 `set backtrace {past,beyond,...}-main'. Also suggest adding `set
1706 backtrace ...-start' to control backtraces past start. The
1707 problem with `below' is that it stops the `up' command. */
1709 add_setshow_boolean_cmd ("backtrace-below-main", class_obscure
,
1710 &backtrace_below_main
, "\
1711 Set whether backtraces should continue past \"main\".\n\
1712 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
1713 the backtrace at \"main\". Set this variable if you need to see the rest\n\
1714 of the stack trace.", "\
1715 Show whether backtraces should continue past \"main\".\n\
1716 Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
1717 the backtrace at \"main\". Set this variable if you need to see the rest\n\
1718 of the stack trace.",
1719 NULL
, NULL
, &setlist
, &showlist
);
1722 /* Debug this files internals. */
1723 add_show_from_set (add_set_cmd ("frame", class_maintenance
, var_zinteger
,
1724 &frame_debug
, "Set frame debugging.\n\
1725 When non-zero, frame specific internal debugging is enabled.", &setdebuglist
),