gdb/frame.h

   1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1996, 1997,
   4    1998, 1999, 2000, 2001, 2002, 2003, 2004, 2007, 2008
   5    Free Software Foundation, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #if !defined (FRAME_H)
  23 #define FRAME_H 1
  24
  25 /* The following is the intended naming schema for frame functions.
  26    It isn't 100% consistent, but it is aproaching that.  Frame naming
  27    schema:
  28
  29    Prefixes:
  30
  31    get_frame_WHAT...(): Get WHAT from the THIS frame (functionaly
  32    equivalent to THIS->next->unwind->what)
  33
  34    frame_unwind_WHAT...(): Unwind THIS frame's WHAT from the NEXT
  35    frame.
  36
  37    put_frame_WHAT...(): Put a value into this frame (unsafe, need to
  38    invalidate the frame / regcache afterwards) (better name more
  39    strongly hinting at its unsafeness)
  40
  41    safe_....(): Safer version of various functions, doesn't throw an
  42    error (leave this for later?).  Returns non-zero / non-NULL if the
  43    request succeeds, zero / NULL otherwize.
  44
  45    Suffixes:
  46
  47    void /frame/_WHAT(): Read WHAT's value into the buffer parameter.
  48
  49    ULONGEST /frame/_WHAT_unsigned(): Return an unsigned value (the
  50    alternative is *frame_unsigned_WHAT).
  51
  52    LONGEST /frame/_WHAT_signed(): Return WHAT signed value.
  53
  54    What:
  55
  56    /frame/_memory* (frame, coreaddr, len [, buf]): Extract/return
  57    *memory.
  58
  59    /frame/_register* (frame, regnum [, buf]): extract/return register.
  60
  61    CORE_ADDR /frame/_{pc,sp,...} (frame): Resume address, innner most
  62    stack *address, ...
  63
  64    */
  65
  66 struct symtab_and_line;
  67 struct frame_unwind;
  68 struct frame_base;
  69 struct block;
  70 struct gdbarch;
  71 struct ui_file;
  72
  73 /* The frame object.  */
  74
  75 struct frame_info;
  76
  77 /* The frame object's ID.  This provides a per-frame unique identifier
  78    that can be used to relocate a `struct frame_info' after a target
  79    resume or a frame cache destruct.  It of course assumes that the
  80    inferior hasn't unwound the stack past that frame.  */
  81
  82 struct frame_id
  83 {
  84   /* The frame's stack address.  This shall be constant through out
  85      the lifetime of a frame.  Note that this requirement applies to
  86      not just the function body, but also the prologue and (in theory
  87      at least) the epilogue.  Since that value needs to fall either on
  88      the boundary, or within the frame's address range, the frame's
  89      outer-most address (the inner-most address of the previous frame)
  90      is used.  Watch out for all the legacy targets that still use the
  91      function pointer register or stack pointer register.  They are
  92      wrong.
  93
  94      This field is valid only if stack_addr_p is true.  Otherwise, this
  95      frame represents the null frame.  */
  96   CORE_ADDR stack_addr;
  97
  98   /* The frame's code address.  This shall be constant through out the
  99      lifetime of the frame.  While the PC (a.k.a. resume address)
 100      changes as the function is executed, this code address cannot.
 101      Typically, it is set to the address of the entry point of the
 102      frame's function (as returned by get_frame_func).
 103
 104      This field is valid only if code_addr_p is true.  Otherwise, this
 105      frame is considered to have a wildcard code address, i.e. one that
 106      matches every address value in frame comparisons.  */
 107   CORE_ADDR code_addr;
 108
 109   /* The frame's special address.  This shall be constant through out the
 110      lifetime of the frame.  This is used for architectures that may have
 111      frames that do not change the stack but are still distinct and have
 112      some form of distinct identifier (e.g. the ia64 which uses a 2nd
 113      stack for registers).  This field is treated as unordered - i.e. will
 114      not be used in frame ordering comparisons such as frame_id_inner().
 115
 116      This field is valid only if special_addr_p is true.  Otherwise, this
 117      frame is considered to have a wildcard special address, i.e. one that
 118      matches every address value in frame comparisons.  */
 119   CORE_ADDR special_addr;
 120
 121   /* Flags to indicate the above fields have valid contents.  */
 122   unsigned int stack_addr_p : 1;
 123   unsigned int code_addr_p : 1;
 124   unsigned int special_addr_p : 1;
 125 };
 126
 127 /* Methods for constructing and comparing Frame IDs.
 128
 129    NOTE: Given stackless functions A and B, where A calls B (and hence
 130    B is inner-to A).  The relationships: !eq(A,B); !eq(B,A);
 131    !inner(A,B); !inner(B,A); all hold.
 132
 133    This is because, while B is inner-to A, B is not strictly inner-to A.
 134    Being stackless, they have an identical .stack_addr value, and differ
 135    only by their unordered .code_addr and/or .special_addr values.
 136
 137    Because frame_id_inner is only used as a safety net (e.g.,
 138    detect a corrupt stack) the lack of strictness is not a problem.
 139    Code needing to determine an exact relationship between two frames
 140    must instead use frame_id_eq and frame_id_unwind.  For instance,
 141    in the above, to determine that A stepped-into B, the equation
 142    "A.id != B.id && A.id == id_unwind (B)" can be used.  */
 143
 144 /* For convenience.  All fields are zero.  */
 145 extern const struct frame_id null_frame_id;
 146
 147 /* Flag to control debugging.  */
 148
 149 extern int frame_debug;
 150
 151 /* Construct a frame ID.  The first parameter is the frame's constant
 152    stack address (typically the outer-bound), and the second the
 153    frame's constant code address (typically the entry point).
 154    The special identifier address is set to indicate a wild card.  */
 155 extern struct frame_id frame_id_build (CORE_ADDR stack_addr,
 156                                        CORE_ADDR code_addr);
 157
 158 /* Construct a special frame ID.  The first parameter is the frame's constant
 159    stack address (typically the outer-bound), the second is the
 160    frame's constant code address (typically the entry point),
 161    and the third parameter is the frame's special identifier address. */
 162 extern struct frame_id frame_id_build_special (CORE_ADDR stack_addr,
 163                                                CORE_ADDR code_addr,
 164                                                CORE_ADDR special_addr);
 165
 166 /* Construct a wild card frame ID.  The parameter is the frame's constant
 167    stack address (typically the outer-bound).  The code address as well
 168    as the special identifier address are set to indicate wild cards.  */
 169 extern struct frame_id frame_id_build_wild (CORE_ADDR stack_addr);
 170
 171 /* Returns non-zero when L is a valid frame (a valid frame has a
 172    non-zero .base).  */
 173 extern int frame_id_p (struct frame_id l);
 174
 175 /* Returns non-zero when L and R identify the same frame, or, if
 176    either L or R have a zero .func, then the same frame base.  */
 177 extern int frame_id_eq (struct frame_id l, struct frame_id r);
 178
 179 /* Returns non-zero when L is strictly inner-than R (they have
 180    different frame .bases).  Neither L, nor R can be `null'.  See note
 181    above about frameless functions.  */
 182 extern int frame_id_inner (struct gdbarch *gdbarch, struct frame_id l,
 183                            struct frame_id r);
 184
 185 /* Write the internal representation of a frame ID on the specified
 186    stream.  */
 187 extern void fprint_frame_id (struct ui_file *file, struct frame_id id);
 188
 189
 190 /* Frame types.  Some are real, some are signal trampolines, and some
 191    are completely artificial (dummy).  */
 192
 193 enum frame_type
 194 {
 195   /* A true stack frame, created by the target program during normal
 196      execution.  */
 197   NORMAL_FRAME,
 198   /* A fake frame, created by GDB when performing an inferior function
 199      call.  */
 200   DUMMY_FRAME,
 201   /* In a signal handler, various OSs handle this in various ways.
 202      The main thing is that the frame may be far from normal.  */
 203   SIGTRAMP_FRAME,
 204   /* Sentinel or registers frame.  This frame obtains register values
 205      direct from the inferior's registers.  */
 206   SENTINEL_FRAME
 207 };
 208
 209 /* For every stopped thread, GDB tracks two frames: current and
 210    selected.  Current frame is the inner most frame of the selected
 211    thread.  Selected frame is the one being examined by the the GDB
 212    CLI (selected using `up', `down', ...).  The frames are created
 213    on-demand (via get_prev_frame()) and then held in a frame cache.  */
 214 /* FIXME: cagney/2002-11-28: Er, there is a lie here.  If you do the
 215    sequence: `thread 1; up; thread 2; thread 1' you lose thread 1's
 216    selected frame.  At present GDB only tracks the selected frame of
 217    the current thread.  But be warned, that might change.  */
 218 /* FIXME: cagney/2002-11-14: At any time, only one thread's selected
 219    and current frame can be active.  Switching threads causes gdb to
 220    discard all that cached frame information.  Ulgh!  Instead, current
 221    and selected frame should be bound to a thread.  */
 222
 223 /* On demand, create the inner most frame using information found in
 224    the inferior.  If the inner most frame can't be created, throw an
 225    error.  */
 226 extern struct frame_info *get_current_frame (void);
 227
 228 /* Invalidates the frame cache (this function should have been called
 229    invalidate_cached_frames).
 230
 231    FIXME: cagney/2002-11-28: There should be two methods: one that
 232    reverts the thread's selected frame back to current frame (for when
 233    the inferior resumes) and one that does not (for when the user
 234    modifies the target invalidating the frame cache).  */
 235 extern void reinit_frame_cache (void);
 236
 237 /* On demand, create the selected frame and then return it.  If the
 238    selected frame can not be created, this function prints then throws
 239    an error.  When MESSAGE is non-NULL, use it for the error message,
 240    otherwize use a generic error message.  */
 241 /* FIXME: cagney/2002-11-28: At present, when there is no selected
 242    frame, this function always returns the current (inner most) frame.
 243    It should instead, when a thread has previously had its frame
 244    selected (but not resumed) and the frame cache invalidated, find
 245    and then return that thread's previously selected frame.  */
 246 extern struct frame_info *get_selected_frame (const char *message);
 247
 248 /* Select a specific frame.  NULL, apparently implies re-select the
 249    inner most frame.  */
 250 extern void select_frame (struct frame_info *);
 251
 252 /* Given a FRAME, return the next (more inner, younger) or previous
 253    (more outer, older) frame.  */
 254 extern struct frame_info *get_prev_frame (struct frame_info *);
 255 extern struct frame_info *get_next_frame (struct frame_info *);
 256
 257 /* Given a frame's ID, relocate the frame.  Returns NULL if the frame
 258    is not found.  */
 259 extern struct frame_info *frame_find_by_id (struct frame_id id);
 260
 261 /* Base attributes of a frame: */
 262
 263 /* The frame's `resume' address.  Where the program will resume in
 264    this frame.
 265
 266    This replaced: frame->pc; */
 267 extern CORE_ADDR get_frame_pc (struct frame_info *);
 268
 269 /* An address (not necessarily aligned to an instruction boundary)
 270    that falls within THIS frame's code block.
 271
 272    When a function call is the last statement in a block, the return
 273    address for the call may land at the start of the next block.
 274    Similarly, if a no-return function call is the last statement in
 275    the function, the return address may end up pointing beyond the
 276    function, and possibly at the start of the next function.
 277
 278    These methods make an allowance for this.  For call frames, this
 279    function returns the frame's PC-1 which "should" be an address in
 280    the frame's block.  */
 281
 282 extern CORE_ADDR get_frame_address_in_block (struct frame_info *this_frame);
 283
 284 /* The frame's inner-most bound.  AKA the stack-pointer.  Confusingly
 285    known as top-of-stack.  */
 286
 287 extern CORE_ADDR get_frame_sp (struct frame_info *);
 288
 289 /* Following on from the `resume' address.  Return the entry point
 290    address of the function containing that resume address, or zero if
 291    that function isn't known.  */
 292 extern CORE_ADDR get_frame_func (struct frame_info *fi);
 293
 294 /* Closely related to the resume address, various symbol table
 295    attributes that are determined by the PC.  Note that for a normal
 296    frame, the PC refers to the resume address after the return, and
 297    not the call instruction.  In such a case, the address is adjusted
 298    so that it (approximately) identifies the call site (and not the
 299    return site).
 300
 301    NOTE: cagney/2002-11-28: The frame cache could be used to cache the
 302    computed value.  Working on the assumption that the bottle-neck is
 303    in the single step code, and that code causes the frame cache to be
 304    constantly flushed, caching things in a frame is probably of little
 305    benefit.  As they say `show us the numbers'.
 306
 307    NOTE: cagney/2002-11-28: Plenty more where this one came from:
 308    find_frame_block(), find_frame_partial_function(),
 309    find_frame_symtab(), find_frame_function().  Each will need to be
 310    carefully considered to determine if the real intent was for it to
 311    apply to the PC or the adjusted PC.  */
 312 extern void find_frame_sal (struct frame_info *frame,
 313                             struct symtab_and_line *sal);
 314
 315 /* Set the current source and line to the location given by frame
 316    FRAME, if possible.  When CENTER is true, adjust so the relevant
 317    line is in the center of the next 'list'.  */
 318
 319 void set_current_sal_from_frame (struct frame_info *, int);
 320
 321 /* Return the frame base (what ever that is) (DEPRECATED).
 322
 323    Old code was trying to use this single method for two conflicting
 324    purposes.  Such code needs to be updated to use either of:
 325
 326    get_frame_id: A low level frame unique identifier, that consists of
 327    both a stack and a function address, that can be used to uniquely
 328    identify a frame.  This value is determined by the frame's
 329    low-level unwinder, the stack part [typically] being the
 330    top-of-stack of the previous frame, and the function part being the
 331    function's start address.  Since the correct identification of a
 332    frameless function requires both the a stack and function address,
 333    the old get_frame_base method was not sufficient.
 334
 335    get_frame_base_address: get_frame_locals_address:
 336    get_frame_args_address: A set of high-level debug-info dependant
 337    addresses that fall within the frame.  These addresses almost
 338    certainly will not match the stack address part of a frame ID (as
 339    returned by get_frame_base).
 340
 341    This replaced: frame->frame; */
 342
 343 extern CORE_ADDR get_frame_base (struct frame_info *);
 344
 345 /* Return the per-frame unique identifer.  Can be used to relocate a
 346    frame after a frame cache flush (and other similar operations).  If
 347    FI is NULL, return the null_frame_id.
 348
 349    NOTE: kettenis/20040508: These functions return a structure.  On
 350    platforms where structures are returned in static storage (vax,
 351    m68k), this may trigger compiler bugs in code like:
 352
 353    if (frame_id_eq (get_frame_id (l), get_frame_id (r)))
 354
 355    where the return value from the first get_frame_id (l) gets
 356    overwritten by the second get_frame_id (r).  Please avoid writing
 357    code like this.  Use code like:
 358
 359    struct frame_id id = get_frame_id (l);
 360    if (frame_id_eq (id, get_frame_id (r)))
 361
 362    instead, since that avoids the bug.  */
 363 extern struct frame_id get_frame_id (struct frame_info *fi);
 364 extern struct frame_id frame_unwind_id (struct frame_info *next_frame);
 365
 366 /* Assuming that a frame is `normal', return its base-address, or 0 if
 367    the information isn't available.  NOTE: This address is really only
 368    meaningful to the frame's high-level debug info.  */
 369 extern CORE_ADDR get_frame_base_address (struct frame_info *);
 370
 371 /* Assuming that a frame is `normal', return the base-address of the
 372    local variables, or 0 if the information isn't available.  NOTE:
 373    This address is really only meaningful to the frame's high-level
 374    debug info.  Typically, the argument and locals share a single
 375    base-address.  */
 376 extern CORE_ADDR get_frame_locals_address (struct frame_info *);
 377
 378 /* Assuming that a frame is `normal', return the base-address of the
 379    parameter list, or 0 if that information isn't available.  NOTE:
 380    This address is really only meaningful to the frame's high-level
 381    debug info.  Typically, the argument and locals share a single
 382    base-address.  */
 383 extern CORE_ADDR get_frame_args_address (struct frame_info *);
 384
 385 /* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
 386    for an invalid frame).  */
 387 extern int frame_relative_level (struct frame_info *fi);
 388
 389 /* Return the frame's type.  */
 390
 391 extern enum frame_type get_frame_type (struct frame_info *);
 392
 393 /* For frames where we can not unwind further, describe why.  */
 394
 395 enum unwind_stop_reason
 396   {
 397     /* No particular reason; either we haven't tried unwinding yet,
 398        or we didn't fail.  */
 399     UNWIND_NO_REASON,
 400
 401     /* The previous frame's analyzer returns an invalid result
 402        from this_id.
 403
 404        FIXME drow/2006-08-16: This is how GDB used to indicate end of
 405        stack.  We should migrate to a model where frames always have a
 406        valid ID, and this becomes not just an error but an internal
 407        error.  But that's a project for another day.  */
 408     UNWIND_NULL_ID,
 409
 410     /* All the conditions after this point are considered errors;
 411        abnormal stack termination.  If a backtrace stops for one
 412        of these reasons, we'll let the user know.  This marker
 413        is not a valid stop reason.  */
 414     UNWIND_FIRST_ERROR,
 415
 416     /* This frame ID looks like it ought to belong to a NEXT frame,
 417        but we got it for a PREV frame.  Normally, this is a sign of
 418        unwinder failure.  It could also indicate stack corruption.  */
 419     UNWIND_INNER_ID,
 420
 421     /* This frame has the same ID as the previous one.  That means
 422        that unwinding further would almost certainly give us another
 423        frame with exactly the same ID, so break the chain.  Normally,
 424        this is a sign of unwinder failure.  It could also indicate
 425        stack corruption.  */
 426     UNWIND_SAME_ID,
 427
 428     /* The frame unwinder didn't find any saved PC, but we needed
 429        one to unwind further.  */
 430     UNWIND_NO_SAVED_PC,
 431   };
 432
 433 /* Return the reason why we can't unwind past this frame.  */
 434
 435 enum unwind_stop_reason get_frame_unwind_stop_reason (struct frame_info *);
 436
 437 /* Translate a reason code to an informative string.  */
 438
 439 const char *frame_stop_reason_string (enum unwind_stop_reason);
 440
 441 /* Unwind the stack frame so that the value of REGNUM, in the previous
 442    (up, older) frame is returned.  If VALUEP is NULL, don't
 443    fetch/compute the value.  Instead just return the location of the
 444    value.  */
 445 extern void frame_register_unwind (struct frame_info *frame, int regnum,
 446                                    int *optimizedp, enum lval_type *lvalp,
 447                                    CORE_ADDR *addrp, int *realnump,
 448                                    gdb_byte *valuep);
 449
 450 /* Fetch a register from this, or unwind a register from the next
 451    frame.  Note that the get_frame methods are wrappers to
 452    frame->next->unwind.  They all [potentially] throw an error if the
 453    fetch fails.  The value methods never return NULL, but usually
 454    do return a lazy value.  */
 455
 456 extern void frame_unwind_register (struct frame_info *frame,
 457                                    int regnum, gdb_byte *buf);
 458 extern void get_frame_register (struct frame_info *frame,
 459                                 int regnum, gdb_byte *buf);
 460
 461 struct value *frame_unwind_register_value (struct frame_info *frame,
 462                                            int regnum);
 463 struct value *get_frame_register_value (struct frame_info *frame,
 464                                         int regnum);
 465
 466 extern LONGEST frame_unwind_register_signed (struct frame_info *frame,
 467                                              int regnum);
 468 extern LONGEST get_frame_register_signed (struct frame_info *frame,
 469                                           int regnum);
 470 extern ULONGEST frame_unwind_register_unsigned (struct frame_info *frame,
 471                                                int regnum);
 472 extern ULONGEST get_frame_register_unsigned (struct frame_info *frame,
 473                                              int regnum);
 474
 475
 476 /* Get the value of the register that belongs to this FRAME.  This
 477    function is a wrapper to the call sequence ``frame_register_unwind
 478    (get_next_frame (FRAME))''.  As per frame_register_unwind(), if
 479    VALUEP is NULL, the registers value is not fetched/computed.  */
 480
 481 extern void frame_register (struct frame_info *frame, int regnum,
 482                             int *optimizedp, enum lval_type *lvalp,
 483                             CORE_ADDR *addrp, int *realnump,
 484                             gdb_byte *valuep);
 485
 486 /* The reverse.  Store a register value relative to the specified
 487    frame.  Note: this call makes the frame's state undefined.  The
 488    register and frame caches must be flushed.  */
 489 extern void put_frame_register (struct frame_info *frame, int regnum,
 490                                 const gdb_byte *buf);
 491
 492 /* Read LEN bytes from one or multiple registers starting with REGNUM
 493    in frame FRAME, starting at OFFSET, into BUF.  */
 494 extern int get_frame_register_bytes (struct frame_info *frame, int regnum,
 495                                      CORE_ADDR offset, int len,
 496                                      gdb_byte *myaddr);
 497
 498 /* Write LEN bytes to one or multiple registers starting with REGNUM
 499    in frame FRAME, starting at OFFSET, into BUF.  */
 500 extern void put_frame_register_bytes (struct frame_info *frame, int regnum,
 501                                       CORE_ADDR offset, int len,
 502                                       const gdb_byte *myaddr);
 503
 504 /* Unwind the PC.  Strictly speaking return the resume address of the
 505    calling frame.  For GDB, `pc' is the resume address and not a
 506    specific register.  */
 507
 508 extern CORE_ADDR frame_pc_unwind (struct frame_info *frame);
 509
 510 /* Discard the specified frame.  Restoring the registers to the state
 511    of the caller.  */
 512 extern void frame_pop (struct frame_info *frame);
 513
 514 /* Return memory from the specified frame.  A frame knows its thread /
 515    LWP and hence can find its way down to a target.  The assumption
 516    here is that the current and previous frame share a common address
 517    space.
 518
 519    If the memory read fails, these methods throw an error.
 520
 521    NOTE: cagney/2003-06-03: Should there be unwind versions of these
 522    methods?  That isn't clear.  Can code, for instance, assume that
 523    this and the previous frame's memory or architecture are identical?
 524    If architecture / memory changes are always separated by special
 525    adaptor frames this should be ok.  */
 526
 527 extern void get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
 528                               gdb_byte *buf, int len);
 529 extern LONGEST get_frame_memory_signed (struct frame_info *this_frame,
 530                                         CORE_ADDR memaddr, int len);
 531 extern ULONGEST get_frame_memory_unsigned (struct frame_info *this_frame,
 532                                            CORE_ADDR memaddr, int len);
 533
 534 /* Same as above, but return non-zero when the entire memory read
 535    succeeds, zero otherwize.  */
 536 extern int safe_frame_unwind_memory (struct frame_info *this_frame,
 537                                      CORE_ADDR addr, gdb_byte *buf, int len);
 538
 539 /* Return this frame's architecture.  */
 540
 541 extern struct gdbarch *get_frame_arch (struct frame_info *this_frame);
 542
 543
 544 /* Values for the source flag to be used in print_frame_info_base().  */
 545 enum print_what
 546   {
 547     /* Print only the source line, like in stepi. */
 548     SRC_LINE = -1,
 549     /* Print only the location, i.e. level, address (sometimes)
 550        function, args, file, line, line num. */
 551     LOCATION,
 552     /* Print both of the above. */
 553     SRC_AND_LOC,
 554     /* Print location only, but always include the address. */
 555     LOC_AND_ADDRESS
 556   };
 557
 558 /* Allocate zero initialized memory from the frame cache obstack.
 559    Appendices to the frame info (such as the unwind cache) should
 560    allocate memory using this method.  */
 561
 562 extern void *frame_obstack_zalloc (unsigned long size);
 563 #define FRAME_OBSTACK_ZALLOC(TYPE) ((TYPE *) frame_obstack_zalloc (sizeof (TYPE)))
 564 #define FRAME_OBSTACK_CALLOC(NUMBER,TYPE) ((TYPE *) frame_obstack_zalloc ((NUMBER) * sizeof (TYPE)))
 565
 566 /* Create a regcache, and copy the frame's registers into it.  */
 567 struct regcache *frame_save_as_regcache (struct frame_info *this_frame);
 568
 569 extern struct block *get_frame_block (struct frame_info *,
 570                                       CORE_ADDR *addr_in_block);
 571
 572 /* Return the `struct block' that belongs to the selected thread's
 573    selected frame.  If the inferior has no state, return NULL.
 574
 575    NOTE: cagney/2002-11-29:
 576
 577    No state?  Does the inferior have any execution state (a core file
 578    does, an executable does not).  At present the code tests
 579    `target_has_stack' but I'm left wondering if it should test
 580    `target_has_registers' or, even, a merged target_has_state.
 581
 582    Should it look at the most recently specified SAL?  If the target
 583    has no state, should this function try to extract a block from the
 584    most recently selected SAL?  That way `list foo' would give it some
 585    sort of reference point.  Then again, perhaps that would confuse
 586    things.
 587
 588    Calls to this function can be broken down into two categories: Code
 589    that uses the selected block as an additional, but optional, data
 590    point; Code that uses the selected block as a prop, when it should
 591    have the relevant frame/block/pc explicitly passed in.
 592
 593    The latter can be eliminated by correctly parameterizing the code,
 594    the former though is more interesting.  Per the "address" command,
 595    it occurs in the CLI code and makes it possible for commands to
 596    work, even when the inferior has no state.  */
 597
 598 extern struct block *get_selected_block (CORE_ADDR *addr_in_block);
 599
 600 extern struct symbol *get_frame_function (struct frame_info *);
 601
 602 extern CORE_ADDR get_pc_function_start (CORE_ADDR);
 603
 604 extern struct frame_info *find_relative_frame (struct frame_info *, int *);
 605
 606 extern void show_and_print_stack_frame (struct frame_info *fi, int print_level,
 607                                         enum print_what print_what);
 608
 609 extern void print_stack_frame (struct frame_info *, int print_level,
 610                                enum print_what print_what);
 611
 612 extern void print_frame_info (struct frame_info *, int print_level,
 613                               enum print_what print_what, int args);
 614
 615 extern struct frame_info *block_innermost_frame (struct block *);
 616
 617 extern int deprecated_pc_in_call_dummy (CORE_ADDR pc);
 618
 619 /* FIXME: cagney/2003-02-02: Should be deprecated or replaced with a
 620    function called get_frame_register_p().  This slightly weird (and
 621    older) variant of get_frame_register() returns zero (indicating the
 622    register is unavailable) if either: the register isn't cached; or
 623    the register has been optimized out.  Problem is, neither check is
 624    exactly correct.  A register can't be optimized out (it may not
 625    have been saved as part of a function call); The fact that a
 626    register isn't in the register cache doesn't mean that the register
 627    isn't available (it could have been fetched from memory).  */
 628
 629 extern int frame_register_read (struct frame_info *frame, int regnum,
 630                                 gdb_byte *buf);
 631
 632 /* From stack.c.  */
 633 extern void args_info (char *, int);
 634
 635 extern void locals_info (char *, int);
 636
 637 extern void (*deprecated_selected_frame_level_changed_hook) (int);
 638
 639 extern void return_command (char *, int);
 640
 641 /* Set FRAME's unwinder temporarily, so that we can call a sniffer.
 642    Return a cleanup which should be called if unwinding fails, and
 643    discarded if it succeeds.  */
 644
 645 struct cleanup *frame_prepare_for_sniffer (struct frame_info *frame,
 646                                            const struct frame_unwind *unwind);
 647
 648 /* Notes (cagney/2002-11-27, drow/2003-09-06):
 649
 650    You might think that calls to this function can simply be replaced by a
 651    call to get_selected_frame().
 652
 653    Unfortunately, it isn't that easy.
 654
 655    The relevant code needs to be audited to determine if it is
 656    possible (or practical) to instead pass the applicable frame in as a
 657    parameter.  For instance, DEPRECATED_DO_REGISTERS_INFO() relied on
 658    the deprecated_selected_frame global, while its replacement,
 659    PRINT_REGISTERS_INFO(), is parameterized with the selected frame.
 660    The only real exceptions occur at the edge (in the CLI code) where
 661    user commands need to pick up the selected frame before proceeding.
 662
 663    There are also some functions called with a NULL frame meaning either "the
 664    program is not running" or "use the selected frame".
 665
 666    This is important.  GDB is trying to stamp out the hack:
 667
 668    saved_frame = deprecated_safe_get_selected_frame ();
 669    select_frame (...);
 670    hack_using_global_selected_frame ();
 671    select_frame (saved_frame);
 672
 673    Take care!
 674
 675    This function calls get_selected_frame if the inferior should have a
 676    frame, or returns NULL otherwise.  */
 677
 678 extern struct frame_info *deprecated_safe_get_selected_frame (void);
 679
 680 /* Create a frame using the specified BASE and PC.  */
 681
 682 extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc);
 683
 684 /* FIXME: cagney/2002-12-06: Has the PC in the current frame changed?
 685    "infrun.c", Thanks to gdbarch_decr_pc_after_break, can change the PC after
 686    the initial frame create.  This puts things back in sync.
 687
 688    This replaced: frame->pc = ....; */
 689 extern void deprecated_update_frame_pc_hack (struct frame_info *frame,
 690                                              CORE_ADDR pc);
 691
 692 /* FIXME: cagney/2002-12-18: Has the frame's base changed?  Or to be
 693    more exact, was that initial guess at the frame's base as returned
 694    by the deleted read_fp() wrong?  If it was, fix it.  This shouldn't
 695    be necessary since the code should be getting the frame's base
 696    correct from the outset.
 697
 698    This replaced: frame->frame = ....; */
 699 extern void deprecated_update_frame_base_hack (struct frame_info *frame,
 700                                                CORE_ADDR base);
 701
 702 #endif /* !defined (FRAME_H)  */