xref: /dragonfly/contrib/gdb-7/gdb/frame.h (revision c3762235)
1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
2 
3    Copyright (C) 1986-2013 Free Software Foundation, Inc.
4 
5    This file is part of GDB.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 #if !defined (FRAME_H)
21 #define FRAME_H 1
22 
23 /* The following is the intended naming schema for frame functions.
24    It isn't 100% consistent, but it is aproaching that.  Frame naming
25    schema:
26 
27    Prefixes:
28 
29    get_frame_WHAT...(): Get WHAT from the THIS frame (functionaly
30    equivalent to THIS->next->unwind->what)
31 
32    frame_unwind_WHAT...(): Unwind THIS frame's WHAT from the NEXT
33    frame.
34 
35    frame_unwind_caller_WHAT...(): Unwind WHAT for NEXT stack frame's
36    real caller.  Any inlined functions in NEXT's stack frame are
37    skipped.  Use these to ignore any potentially inlined functions,
38    e.g. inlined into the first instruction of a library trampoline.
39 
40    get_stack_frame_WHAT...(): Get WHAT for THIS frame, but if THIS is
41    inlined, skip to the containing stack frame.
42 
43    put_frame_WHAT...(): Put a value into this frame (unsafe, need to
44    invalidate the frame / regcache afterwards) (better name more
45    strongly hinting at its unsafeness)
46 
47    safe_....(): Safer version of various functions, doesn't throw an
48    error (leave this for later?).  Returns non-zero / non-NULL if the
49    request succeeds, zero / NULL otherwize.
50 
51    Suffixes:
52 
53    void /frame/_WHAT(): Read WHAT's value into the buffer parameter.
54 
55    ULONGEST /frame/_WHAT_unsigned(): Return an unsigned value (the
56    alternative is *frame_unsigned_WHAT).
57 
58    LONGEST /frame/_WHAT_signed(): Return WHAT signed value.
59 
60    What:
61 
62    /frame/_memory* (frame, coreaddr, len [, buf]): Extract/return
63    *memory.
64 
65    /frame/_register* (frame, regnum [, buf]): extract/return register.
66 
67    CORE_ADDR /frame/_{pc,sp,...} (frame): Resume address, innner most
68    stack *address, ...
69 
70    */
71 
72 struct symtab_and_line;
73 struct frame_unwind;
74 struct frame_base;
75 struct block;
76 struct gdbarch;
77 struct ui_file;
78 
79 /* The frame object.  */
80 
81 struct frame_info;
82 
83 /* The frame object's ID.  This provides a per-frame unique identifier
84    that can be used to relocate a `struct frame_info' after a target
85    resume or a frame cache destruct.  It of course assumes that the
86    inferior hasn't unwound the stack past that frame.  */
87 
88 struct frame_id
89 {
90   /* The frame's stack address.  This shall be constant through out
91      the lifetime of a frame.  Note that this requirement applies to
92      not just the function body, but also the prologue and (in theory
93      at least) the epilogue.  Since that value needs to fall either on
94      the boundary, or within the frame's address range, the frame's
95      outer-most address (the inner-most address of the previous frame)
96      is used.  Watch out for all the legacy targets that still use the
97      function pointer register or stack pointer register.  They are
98      wrong.
99 
100      This field is valid only if stack_addr_p is true.  Otherwise, this
101      frame represents the null frame.  */
102   CORE_ADDR stack_addr;
103 
104   /* The frame's code address.  This shall be constant through out the
105      lifetime of the frame.  While the PC (a.k.a. resume address)
106      changes as the function is executed, this code address cannot.
107      Typically, it is set to the address of the entry point of the
108      frame's function (as returned by get_frame_func).
109 
110      For inlined functions (INLINE_DEPTH != 0), this is the address of
111      the first executed instruction in the block corresponding to the
112      inlined function.
113 
114      This field is valid only if code_addr_p is true.  Otherwise, this
115      frame is considered to have a wildcard code address, i.e. one that
116      matches every address value in frame comparisons.  */
117   CORE_ADDR code_addr;
118 
119   /* The frame's special address.  This shall be constant through out the
120      lifetime of the frame.  This is used for architectures that may have
121      frames that do not change the stack but are still distinct and have
122      some form of distinct identifier (e.g. the ia64 which uses a 2nd
123      stack for registers).  This field is treated as unordered - i.e. will
124      not be used in frame ordering comparisons.
125 
126      This field is valid only if special_addr_p is true.  Otherwise, this
127      frame is considered to have a wildcard special address, i.e. one that
128      matches every address value in frame comparisons.  */
129   CORE_ADDR special_addr;
130 
131   /* Flags to indicate the above fields have valid contents.  */
132   unsigned int stack_addr_p : 1;
133   unsigned int code_addr_p : 1;
134   unsigned int special_addr_p : 1;
135 
136   /* It is non-zero for a frame made up by GDB without stack data
137      representation in inferior, such as INLINE_FRAME or TAILCALL_FRAME.
138      Caller of inlined function will have it zero, each more inner called frame
139      will have it increasingly one, two etc.  Similarly for TAILCALL_FRAME.  */
140   int artificial_depth;
141 };
142 
143 /* Methods for constructing and comparing Frame IDs.  */
144 
145 /* For convenience.  All fields are zero.  This means "there is no frame".  */
146 extern const struct frame_id null_frame_id;
147 
148 /* This means "there is no frame ID, but there is a frame".  It should be
149    replaced by best-effort frame IDs for the outermost frame, somehow.
150    The implementation is only special_addr_p set.  */
151 extern const struct frame_id outer_frame_id;
152 
153 /* Flag to control debugging.  */
154 
155 extern unsigned int frame_debug;
156 
157 /* Construct a frame ID.  The first parameter is the frame's constant
158    stack address (typically the outer-bound), and the second the
159    frame's constant code address (typically the entry point).
160    The special identifier address is set to indicate a wild card.  */
161 extern struct frame_id frame_id_build (CORE_ADDR stack_addr,
162 				       CORE_ADDR code_addr);
163 
164 /* Construct a special frame ID.  The first parameter is the frame's constant
165    stack address (typically the outer-bound), the second is the
166    frame's constant code address (typically the entry point),
167    and the third parameter is the frame's special identifier address.  */
168 extern struct frame_id frame_id_build_special (CORE_ADDR stack_addr,
169 					       CORE_ADDR code_addr,
170 					       CORE_ADDR special_addr);
171 
172 /* Construct a wild card frame ID.  The parameter is the frame's constant
173    stack address (typically the outer-bound).  The code address as well
174    as the special identifier address are set to indicate wild cards.  */
175 extern struct frame_id frame_id_build_wild (CORE_ADDR stack_addr);
176 
177 /* Returns non-zero when L is a valid frame (a valid frame has a
178    non-zero .base).  The outermost frame is valid even without an
179    ID.  */
180 extern int frame_id_p (struct frame_id l);
181 
182 /* Returns non-zero when L is a valid frame representing a frame made up by GDB
183    without stack data representation in inferior, such as INLINE_FRAME or
184    TAILCALL_FRAME.  */
185 extern int frame_id_artificial_p (struct frame_id l);
186 
187 /* Returns non-zero when L and R identify the same frame, or, if
188    either L or R have a zero .func, then the same frame base.  */
189 extern int frame_id_eq (struct frame_id l, struct frame_id r);
190 
191 /* Write the internal representation of a frame ID on the specified
192    stream.  */
193 extern void fprint_frame_id (struct ui_file *file, struct frame_id id);
194 
195 
196 /* Frame types.  Some are real, some are signal trampolines, and some
197    are completely artificial (dummy).  */
198 
199 enum frame_type
200 {
201   /* A true stack frame, created by the target program during normal
202      execution.  */
203   NORMAL_FRAME,
204   /* A fake frame, created by GDB when performing an inferior function
205      call.  */
206   DUMMY_FRAME,
207   /* A frame representing an inlined function, associated with an
208      upcoming (prev, outer, older) NORMAL_FRAME.  */
209   INLINE_FRAME,
210   /* A virtual frame of a tail call - see dwarf2_tailcall_frame_unwind.  */
211   TAILCALL_FRAME,
212   /* In a signal handler, various OSs handle this in various ways.
213      The main thing is that the frame may be far from normal.  */
214   SIGTRAMP_FRAME,
215   /* Fake frame representing a cross-architecture call.  */
216   ARCH_FRAME,
217   /* Sentinel or registers frame.  This frame obtains register values
218      direct from the inferior's registers.  */
219   SENTINEL_FRAME
220 };
221 
222 /* For every stopped thread, GDB tracks two frames: current and
223    selected.  Current frame is the inner most frame of the selected
224    thread.  Selected frame is the one being examined by the GDB
225    CLI (selected using `up', `down', ...).  The frames are created
226    on-demand (via get_prev_frame()) and then held in a frame cache.  */
227 /* FIXME: cagney/2002-11-28: Er, there is a lie here.  If you do the
228    sequence: `thread 1; up; thread 2; thread 1' you lose thread 1's
229    selected frame.  At present GDB only tracks the selected frame of
230    the current thread.  But be warned, that might change.  */
231 /* FIXME: cagney/2002-11-14: At any time, only one thread's selected
232    and current frame can be active.  Switching threads causes gdb to
233    discard all that cached frame information.  Ulgh!  Instead, current
234    and selected frame should be bound to a thread.  */
235 
236 /* On demand, create the inner most frame using information found in
237    the inferior.  If the inner most frame can't be created, throw an
238    error.  */
239 extern struct frame_info *get_current_frame (void);
240 
241 /* Does the current target interface have enough state to be able to
242    query the current inferior for frame info, and is the inferior in a
243    state where that is possible?  */
244 extern int has_stack_frames (void);
245 
246 /* Invalidates the frame cache (this function should have been called
247    invalidate_cached_frames).
248 
249    FIXME: cagney/2002-11-28: There should be two methods: one that
250    reverts the thread's selected frame back to current frame (for when
251    the inferior resumes) and one that does not (for when the user
252    modifies the target invalidating the frame cache).  */
253 extern void reinit_frame_cache (void);
254 
255 /* On demand, create the selected frame and then return it.  If the
256    selected frame can not be created, this function prints then throws
257    an error.  When MESSAGE is non-NULL, use it for the error message,
258    otherwize use a generic error message.  */
259 /* FIXME: cagney/2002-11-28: At present, when there is no selected
260    frame, this function always returns the current (inner most) frame.
261    It should instead, when a thread has previously had its frame
262    selected (but not resumed) and the frame cache invalidated, find
263    and then return that thread's previously selected frame.  */
264 extern struct frame_info *get_selected_frame (const char *message);
265 
266 /* If there is a selected frame, return it.  Otherwise, return NULL.  */
267 extern struct frame_info *get_selected_frame_if_set (void);
268 
269 /* Select a specific frame.  NULL, apparently implies re-select the
270    inner most frame.  */
271 extern void select_frame (struct frame_info *);
272 
273 /* Given a FRAME, return the next (more inner, younger) or previous
274    (more outer, older) frame.  */
275 extern struct frame_info *get_prev_frame (struct frame_info *);
276 extern struct frame_info *get_next_frame (struct frame_info *);
277 
278 /* Given a frame's ID, relocate the frame.  Returns NULL if the frame
279    is not found.  */
280 extern struct frame_info *frame_find_by_id (struct frame_id id);
281 
282 /* Base attributes of a frame: */
283 
284 /* The frame's `resume' address.  Where the program will resume in
285    this frame.
286 
287    This replaced: frame->pc; */
288 extern CORE_ADDR get_frame_pc (struct frame_info *);
289 
290 /* Same as get_frame_pc, but return a boolean indication of whether
291    the PC is actually available, instead of throwing an error.  */
292 
293 extern int get_frame_pc_if_available (struct frame_info *frame,
294 				      CORE_ADDR *pc);
295 
296 /* An address (not necessarily aligned to an instruction boundary)
297    that falls within THIS frame's code block.
298 
299    When a function call is the last statement in a block, the return
300    address for the call may land at the start of the next block.
301    Similarly, if a no-return function call is the last statement in
302    the function, the return address may end up pointing beyond the
303    function, and possibly at the start of the next function.
304 
305    These methods make an allowance for this.  For call frames, this
306    function returns the frame's PC-1 which "should" be an address in
307    the frame's block.  */
308 
309 extern CORE_ADDR get_frame_address_in_block (struct frame_info *this_frame);
310 
311 /* Same as get_frame_address_in_block, but returns a boolean
312    indication of whether the frame address is determinable (when the
313    PC is unavailable, it will not be), instead of possibly throwing an
314    error trying to read an unavailable PC.  */
315 
316 extern int
317   get_frame_address_in_block_if_available (struct frame_info *this_frame,
318 					   CORE_ADDR *pc);
319 
320 /* The frame's inner-most bound.  AKA the stack-pointer.  Confusingly
321    known as top-of-stack.  */
322 
323 extern CORE_ADDR get_frame_sp (struct frame_info *);
324 
325 /* Following on from the `resume' address.  Return the entry point
326    address of the function containing that resume address, or zero if
327    that function isn't known.  */
328 extern CORE_ADDR get_frame_func (struct frame_info *fi);
329 
330 /* Same as get_frame_func, but returns a boolean indication of whether
331    the frame function is determinable (when the PC is unavailable, it
332    will not be), instead of possibly throwing an error trying to read
333    an unavailable PC.  */
334 
335 extern int get_frame_func_if_available (struct frame_info *fi, CORE_ADDR *);
336 
337 /* Closely related to the resume address, various symbol table
338    attributes that are determined by the PC.  Note that for a normal
339    frame, the PC refers to the resume address after the return, and
340    not the call instruction.  In such a case, the address is adjusted
341    so that it (approximately) identifies the call site (and not the
342    return site).
343 
344    NOTE: cagney/2002-11-28: The frame cache could be used to cache the
345    computed value.  Working on the assumption that the bottle-neck is
346    in the single step code, and that code causes the frame cache to be
347    constantly flushed, caching things in a frame is probably of little
348    benefit.  As they say `show us the numbers'.
349 
350    NOTE: cagney/2002-11-28: Plenty more where this one came from:
351    find_frame_block(), find_frame_partial_function(),
352    find_frame_symtab(), find_frame_function().  Each will need to be
353    carefully considered to determine if the real intent was for it to
354    apply to the PC or the adjusted PC.  */
355 extern void find_frame_sal (struct frame_info *frame,
356 			    struct symtab_and_line *sal);
357 
358 /* Set the current source and line to the location given by frame
359    FRAME, if possible.  When CENTER is true, adjust so the relevant
360    line is in the center of the next 'list'.  */
361 
362 void set_current_sal_from_frame (struct frame_info *, int);
363 
364 /* Return the frame base (what ever that is) (DEPRECATED).
365 
366    Old code was trying to use this single method for two conflicting
367    purposes.  Such code needs to be updated to use either of:
368 
369    get_frame_id: A low level frame unique identifier, that consists of
370    both a stack and a function address, that can be used to uniquely
371    identify a frame.  This value is determined by the frame's
372    low-level unwinder, the stack part [typically] being the
373    top-of-stack of the previous frame, and the function part being the
374    function's start address.  Since the correct identification of a
375    frameless function requires both a stack and function address,
376    the old get_frame_base method was not sufficient.
377 
378    get_frame_base_address: get_frame_locals_address:
379    get_frame_args_address: A set of high-level debug-info dependant
380    addresses that fall within the frame.  These addresses almost
381    certainly will not match the stack address part of a frame ID (as
382    returned by get_frame_base).
383 
384    This replaced: frame->frame; */
385 
386 extern CORE_ADDR get_frame_base (struct frame_info *);
387 
388 /* Return the per-frame unique identifer.  Can be used to relocate a
389    frame after a frame cache flush (and other similar operations).  If
390    FI is NULL, return the null_frame_id.
391 
392    NOTE: kettenis/20040508: These functions return a structure.  On
393    platforms where structures are returned in static storage (vax,
394    m68k), this may trigger compiler bugs in code like:
395 
396    if (frame_id_eq (get_frame_id (l), get_frame_id (r)))
397 
398    where the return value from the first get_frame_id (l) gets
399    overwritten by the second get_frame_id (r).  Please avoid writing
400    code like this.  Use code like:
401 
402    struct frame_id id = get_frame_id (l);
403    if (frame_id_eq (id, get_frame_id (r)))
404 
405    instead, since that avoids the bug.  */
406 extern struct frame_id get_frame_id (struct frame_info *fi);
407 extern struct frame_id get_stack_frame_id (struct frame_info *fi);
408 extern struct frame_id frame_unwind_caller_id (struct frame_info *next_frame);
409 
410 /* Assuming that a frame is `normal', return its base-address, or 0 if
411    the information isn't available.  NOTE: This address is really only
412    meaningful to the frame's high-level debug info.  */
413 extern CORE_ADDR get_frame_base_address (struct frame_info *);
414 
415 /* Assuming that a frame is `normal', return the base-address of the
416    local variables, or 0 if the information isn't available.  NOTE:
417    This address is really only meaningful to the frame's high-level
418    debug info.  Typically, the argument and locals share a single
419    base-address.  */
420 extern CORE_ADDR get_frame_locals_address (struct frame_info *);
421 
422 /* Assuming that a frame is `normal', return the base-address of the
423    parameter list, or 0 if that information isn't available.  NOTE:
424    This address is really only meaningful to the frame's high-level
425    debug info.  Typically, the argument and locals share a single
426    base-address.  */
427 extern CORE_ADDR get_frame_args_address (struct frame_info *);
428 
429 /* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
430    for an invalid frame).  */
431 extern int frame_relative_level (struct frame_info *fi);
432 
433 /* Return the frame's type.  */
434 
435 extern enum frame_type get_frame_type (struct frame_info *);
436 
437 /* Return the frame's program space.  */
438 extern struct program_space *get_frame_program_space (struct frame_info *);
439 
440 /* Unwind THIS frame's program space from the NEXT frame.  */
441 extern struct program_space *frame_unwind_program_space (struct frame_info *);
442 
443 /* Return the frame's address space.  */
444 extern struct address_space *get_frame_address_space (struct frame_info *);
445 
446 /* For frames where we can not unwind further, describe why.  */
447 
448 enum unwind_stop_reason
449   {
450 #define SET(name, description) name,
451 #define FIRST_ENTRY(name) UNWIND_FIRST = name,
452 #define LAST_ENTRY(name) UNWIND_LAST = name,
453 #define FIRST_ERROR(name) UNWIND_FIRST_ERROR = name,
454 
455 #include "unwind_stop_reasons.def"
456 #undef SET
457 #undef FIRST_ENTRY
458 #undef LAST_ENTRY
459 #undef FIRST_ERROR
460   };
461 
462 /* Return the reason why we can't unwind past this frame.  */
463 
464 enum unwind_stop_reason get_frame_unwind_stop_reason (struct frame_info *);
465 
466 /* Translate a reason code to an informative string.  */
467 
468 const char *frame_stop_reason_string (enum unwind_stop_reason);
469 
470 /* Unwind the stack frame so that the value of REGNUM, in the previous
471    (up, older) frame is returned.  If VALUEP is NULL, don't
472    fetch/compute the value.  Instead just return the location of the
473    value.  */
474 extern void frame_register_unwind (struct frame_info *frame, int regnum,
475 				   int *optimizedp, int *unavailablep,
476 				   enum lval_type *lvalp,
477 				   CORE_ADDR *addrp, int *realnump,
478 				   gdb_byte *valuep);
479 
480 /* Fetch a register from this, or unwind a register from the next
481    frame.  Note that the get_frame methods are wrappers to
482    frame->next->unwind.  They all [potentially] throw an error if the
483    fetch fails.  The value methods never return NULL, but usually
484    do return a lazy value.  */
485 
486 extern void frame_unwind_register (struct frame_info *frame,
487 				   int regnum, gdb_byte *buf);
488 extern void get_frame_register (struct frame_info *frame,
489 				int regnum, gdb_byte *buf);
490 
491 struct value *frame_unwind_register_value (struct frame_info *frame,
492 					   int regnum);
493 struct value *get_frame_register_value (struct frame_info *frame,
494 					int regnum);
495 
496 extern LONGEST frame_unwind_register_signed (struct frame_info *frame,
497 					     int regnum);
498 extern LONGEST get_frame_register_signed (struct frame_info *frame,
499 					  int regnum);
500 extern ULONGEST frame_unwind_register_unsigned (struct frame_info *frame,
501 					       int regnum);
502 extern ULONGEST get_frame_register_unsigned (struct frame_info *frame,
503 					     int regnum);
504 
505 /* Read a register from this, or unwind a register from the next
506    frame.  Note that the read_frame methods are wrappers to
507    get_frame_register_value, that do not throw if the result is
508    optimized out or unavailable.  */
509 
510 extern int read_frame_register_unsigned (struct frame_info *frame,
511 					 int regnum, ULONGEST *val);
512 
513 /* Get the value of the register that belongs to this FRAME.  This
514    function is a wrapper to the call sequence ``frame_register_unwind
515    (get_next_frame (FRAME))''.  As per frame_register_unwind(), if
516    VALUEP is NULL, the registers value is not fetched/computed.  */
517 
518 extern void frame_register (struct frame_info *frame, int regnum,
519 			    int *optimizedp, int *unavailablep,
520 			    enum lval_type *lvalp,
521 			    CORE_ADDR *addrp, int *realnump,
522 			    gdb_byte *valuep);
523 
524 /* The reverse.  Store a register value relative to the specified
525    frame.  Note: this call makes the frame's state undefined.  The
526    register and frame caches must be flushed.  */
527 extern void put_frame_register (struct frame_info *frame, int regnum,
528 				const gdb_byte *buf);
529 
530 /* Read LEN bytes from one or multiple registers starting with REGNUM
531    in frame FRAME, starting at OFFSET, into BUF.  If the register
532    contents are optimized out or unavailable, set *OPTIMIZEDP,
533    *UNAVAILABLEP accordingly.  */
534 extern int get_frame_register_bytes (struct frame_info *frame, int regnum,
535 				     CORE_ADDR offset, int len,
536 				     gdb_byte *myaddr,
537 				     int *optimizedp, int *unavailablep);
538 
539 /* Write LEN bytes to one or multiple registers starting with REGNUM
540    in frame FRAME, starting at OFFSET, into BUF.  */
541 extern void put_frame_register_bytes (struct frame_info *frame, int regnum,
542 				      CORE_ADDR offset, int len,
543 				      const gdb_byte *myaddr);
544 
545 /* Unwind the PC.  Strictly speaking return the resume address of the
546    calling frame.  For GDB, `pc' is the resume address and not a
547    specific register.  */
548 
549 extern CORE_ADDR frame_unwind_caller_pc (struct frame_info *frame);
550 
551 /* Same as frame_unwind_caller_pc, but returns a boolean indication of
552    whether the caller PC is determinable (when the PC is unavailable,
553    it will not be), instead of possibly throwing an error trying to
554    read unavailable memory or registers.  */
555 
556 extern int frame_unwind_caller_pc_if_available (struct frame_info *this_frame,
557 						CORE_ADDR *pc);
558 
559 /* Discard the specified frame.  Restoring the registers to the state
560    of the caller.  */
561 extern void frame_pop (struct frame_info *frame);
562 
563 /* Return memory from the specified frame.  A frame knows its thread /
564    LWP and hence can find its way down to a target.  The assumption
565    here is that the current and previous frame share a common address
566    space.
567 
568    If the memory read fails, these methods throw an error.
569 
570    NOTE: cagney/2003-06-03: Should there be unwind versions of these
571    methods?  That isn't clear.  Can code, for instance, assume that
572    this and the previous frame's memory or architecture are identical?
573    If architecture / memory changes are always separated by special
574    adaptor frames this should be ok.  */
575 
576 extern void get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
577 			      gdb_byte *buf, int len);
578 extern LONGEST get_frame_memory_signed (struct frame_info *this_frame,
579 					CORE_ADDR memaddr, int len);
580 extern ULONGEST get_frame_memory_unsigned (struct frame_info *this_frame,
581 					   CORE_ADDR memaddr, int len);
582 
583 /* Same as above, but return non-zero when the entire memory read
584    succeeds, zero otherwize.  */
585 extern int safe_frame_unwind_memory (struct frame_info *this_frame,
586 				     CORE_ADDR addr, gdb_byte *buf, int len);
587 
588 /* Return this frame's architecture.  */
589 extern struct gdbarch *get_frame_arch (struct frame_info *this_frame);
590 
591 /* Return the previous frame's architecture.  */
592 extern struct gdbarch *frame_unwind_arch (struct frame_info *frame);
593 
594 /* Return the previous frame's architecture, skipping inline functions.  */
595 extern struct gdbarch *frame_unwind_caller_arch (struct frame_info *frame);
596 
597 
598 /* Values for the source flag to be used in print_frame_info_base().  */
599 enum print_what
600   {
601     /* Print only the source line, like in stepi.  */
602     SRC_LINE = -1,
603     /* Print only the location, i.e. level, address (sometimes)
604        function, args, file, line, line num.  */
605     LOCATION,
606     /* Print both of the above.  */
607     SRC_AND_LOC,
608     /* Print location only, but always include the address.  */
609     LOC_AND_ADDRESS
610   };
611 
612 /* Allocate zero initialized memory from the frame cache obstack.
613    Appendices to the frame info (such as the unwind cache) should
614    allocate memory using this method.  */
615 
616 extern void *frame_obstack_zalloc (unsigned long size);
617 #define FRAME_OBSTACK_ZALLOC(TYPE) \
618   ((TYPE *) frame_obstack_zalloc (sizeof (TYPE)))
619 #define FRAME_OBSTACK_CALLOC(NUMBER,TYPE) \
620   ((TYPE *) frame_obstack_zalloc ((NUMBER) * sizeof (TYPE)))
621 
622 /* Create a regcache, and copy the frame's registers into it.  */
623 struct regcache *frame_save_as_regcache (struct frame_info *this_frame);
624 
625 extern struct block *get_frame_block (struct frame_info *,
626                                       CORE_ADDR *addr_in_block);
627 
628 /* Return the `struct block' that belongs to the selected thread's
629    selected frame.  If the inferior has no state, return NULL.
630 
631    NOTE: cagney/2002-11-29:
632 
633    No state?  Does the inferior have any execution state (a core file
634    does, an executable does not).  At present the code tests
635    `target_has_stack' but I'm left wondering if it should test
636    `target_has_registers' or, even, a merged target_has_state.
637 
638    Should it look at the most recently specified SAL?  If the target
639    has no state, should this function try to extract a block from the
640    most recently selected SAL?  That way `list foo' would give it some
641    sort of reference point.  Then again, perhaps that would confuse
642    things.
643 
644    Calls to this function can be broken down into two categories: Code
645    that uses the selected block as an additional, but optional, data
646    point; Code that uses the selected block as a prop, when it should
647    have the relevant frame/block/pc explicitly passed in.
648 
649    The latter can be eliminated by correctly parameterizing the code,
650    the former though is more interesting.  Per the "address" command,
651    it occurs in the CLI code and makes it possible for commands to
652    work, even when the inferior has no state.  */
653 
654 extern struct block *get_selected_block (CORE_ADDR *addr_in_block);
655 
656 extern struct symbol *get_frame_function (struct frame_info *);
657 
658 extern CORE_ADDR get_pc_function_start (CORE_ADDR);
659 
660 extern struct frame_info *find_relative_frame (struct frame_info *, int *);
661 
662 extern void show_and_print_stack_frame (struct frame_info *fi, int print_level,
663 					enum print_what print_what);
664 
665 extern void print_stack_frame (struct frame_info *, int print_level,
666 			       enum print_what print_what);
667 
668 extern void print_frame_info (struct frame_info *, int print_level,
669 			      enum print_what print_what, int args);
670 
671 extern struct frame_info *block_innermost_frame (const struct block *);
672 
673 extern int deprecated_frame_register_read (struct frame_info *frame, int regnum,
674 				gdb_byte *buf);
675 
676 /* From stack.c.  */
677 
678 extern const char print_entry_values_no[];
679 extern const char print_entry_values_only[];
680 extern const char print_entry_values_preferred[];
681 extern const char print_entry_values_if_needed[];
682 extern const char print_entry_values_both[];
683 extern const char print_entry_values_compact[];
684 extern const char print_entry_values_default[];
685 extern const char *print_entry_values;
686 
687 /* Inferior function parameter value read in from a frame.  */
688 
689 struct frame_arg
690 {
691   /* Symbol for this parameter used for example for its name.  */
692   struct symbol *sym;
693 
694   /* Value of the parameter.  It is NULL if ERROR is not NULL; if both VAL and
695      ERROR are NULL this parameter's value should not be printed.  */
696   struct value *val;
697 
698   /* String containing the error message, it is more usually NULL indicating no
699      error occured reading this parameter.  */
700   char *error;
701 
702   /* One of the print_entry_values_* entries as appropriate specifically for
703      this frame_arg.  It will be different from print_entry_values.  With
704      print_entry_values_no this frame_arg should be printed as a normal
705      parameter.  print_entry_values_only says it should be printed as entry
706      value parameter.  print_entry_values_compact says it should be printed as
707      both as a normal parameter and entry values parameter having the same
708      value - print_entry_values_compact is not permitted fi ui_out_is_mi_like_p
709      (in such case print_entry_values_no and print_entry_values_only is used
710      for each parameter kind specifically.  */
711   const char *entry_kind;
712 };
713 
714 extern void read_frame_arg (struct symbol *sym, struct frame_info *frame,
715 			    struct frame_arg *argp,
716 			    struct frame_arg *entryargp);
717 extern void read_frame_local (struct symbol *sym, struct frame_info *frame,
718 			      struct frame_arg *argp);
719 
720 extern void args_info (char *, int);
721 
722 extern void locals_info (char *, int);
723 
724 extern void (*deprecated_selected_frame_level_changed_hook) (int);
725 
726 extern void return_command (char *, int);
727 
728 /* Set FRAME's unwinder temporarily, so that we can call a sniffer.
729    Return a cleanup which should be called if unwinding fails, and
730    discarded if it succeeds.  */
731 
732 struct cleanup *frame_prepare_for_sniffer (struct frame_info *frame,
733 					   const struct frame_unwind *unwind);
734 
735 /* Notes (cagney/2002-11-27, drow/2003-09-06):
736 
737    You might think that calls to this function can simply be replaced by a
738    call to get_selected_frame().
739 
740    Unfortunately, it isn't that easy.
741 
742    The relevant code needs to be audited to determine if it is
743    possible (or practical) to instead pass the applicable frame in as a
744    parameter.  For instance, DEPRECATED_DO_REGISTERS_INFO() relied on
745    the deprecated_selected_frame global, while its replacement,
746    PRINT_REGISTERS_INFO(), is parameterized with the selected frame.
747    The only real exceptions occur at the edge (in the CLI code) where
748    user commands need to pick up the selected frame before proceeding.
749 
750    There are also some functions called with a NULL frame meaning either "the
751    program is not running" or "use the selected frame".
752 
753    This is important.  GDB is trying to stamp out the hack:
754 
755    saved_frame = deprecated_safe_get_selected_frame ();
756    select_frame (...);
757    hack_using_global_selected_frame ();
758    select_frame (saved_frame);
759 
760    Take care!
761 
762    This function calls get_selected_frame if the inferior should have a
763    frame, or returns NULL otherwise.  */
764 
765 extern struct frame_info *deprecated_safe_get_selected_frame (void);
766 
767 /* Create a frame using the specified BASE and PC.  */
768 
769 extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc);
770 
771 /* Return true if the frame unwinder for frame FI is UNWINDER; false
772    otherwise.  */
773 
774 extern int frame_unwinder_is (struct frame_info *fi,
775 			      const struct frame_unwind *unwinder);
776 
777 #endif /* !defined (FRAME_H)  */
778