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, 2009
   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    frame_unwind_caller_WHAT...(): Unwind WHAT for NEXT stack frame's
  38    real caller.  Any inlined functions in NEXT's stack frame are
  39    skipped.  Use these to ignore any potentially inlined functions,
  40    e.g. inlined into the first instruction of a library trampoline.
  41
  42    get_stack_frame_WHAT...(): Get WHAT for THIS frame, but if THIS is
  43    inlined, skip to the containing stack frame.
  44
  45    put_frame_WHAT...(): Put a value into this frame (unsafe, need to
  46    invalidate the frame / regcache afterwards) (better name more
  47    strongly hinting at its unsafeness)
  48
  49    safe_....(): Safer version of various functions, doesn't throw an
  50    error (leave this for later?).  Returns non-zero / non-NULL if the
  51    request succeeds, zero / NULL otherwize.
  52
  53    Suffixes:
  54
  55    void /frame/_WHAT(): Read WHAT's value into the buffer parameter.
  56
  57    ULONGEST /frame/_WHAT_unsigned(): Return an unsigned value (the
  58    alternative is *frame_unsigned_WHAT).
  59
  60    LONGEST /frame/_WHAT_signed(): Return WHAT signed value.
  61
  62    What:
  63
  64    /frame/_memory* (frame, coreaddr, len [, buf]): Extract/return
  65    *memory.
  66
  67    /frame/_register* (frame, regnum [, buf]): extract/return register.
  68
  69    CORE_ADDR /frame/_{pc,sp,...} (frame): Resume address, innner most
  70    stack *address, ...
  71
  72    */
  73
  74 struct symtab_and_line;
  75 struct frame_unwind;
  76 struct frame_base;
  77 struct block;
  78 struct gdbarch;
  79 struct ui_file;
  80
  81 /* The frame object.  */
  82
  83 struct frame_info;
  84
  85 /* The frame object's ID.  This provides a per-frame unique identifier
  86    that can be used to relocate a `struct frame_info' after a target
  87    resume or a frame cache destruct.  It of course assumes that the
  88    inferior hasn't unwound the stack past that frame.  */
  89
  90 struct frame_id
  91 {
  92   /* The frame's stack address.  This shall be constant through out
  93      the lifetime of a frame.  Note that this requirement applies to
  94      not just the function body, but also the prologue and (in theory
  95      at least) the epilogue.  Since that value needs to fall either on
  96      the boundary, or within the frame's address range, the frame's
  97      outer-most address (the inner-most address of the previous frame)
  98      is used.  Watch out for all the legacy targets that still use the
  99      function pointer register or stack pointer register.  They are
 100      wrong.
 101
 102      This field is valid only if stack_addr_p is true.  Otherwise, this
 103      frame represents the null frame.  */
 104   CORE_ADDR stack_addr;
 105
 106   /* The frame's code address.  This shall be constant through out the
 107      lifetime of the frame.  While the PC (a.k.a. resume address)
 108      changes as the function is executed, this code address cannot.
 109      Typically, it is set to the address of the entry point of the
 110      frame's function (as returned by get_frame_func).
 111
 112      For inlined functions (INLINE_DEPTH != 0), this is the address of
 113      the first executed instruction in the block corresponding to the
 114      inlined function.
 115
 116      This field is valid only if code_addr_p is true.  Otherwise, this
 117      frame is considered to have a wildcard code address, i.e. one that
 118      matches every address value in frame comparisons.  */
 119   CORE_ADDR code_addr;
 120
 121   /* The frame's special address.  This shall be constant through out the
 122      lifetime of the frame.  This is used for architectures that may have
 123      frames that do not change the stack but are still distinct and have
 124      some form of distinct identifier (e.g. the ia64 which uses a 2nd
 125      stack for registers).  This field is treated as unordered - i.e. will
 126      not be used in frame ordering comparisons.
 127
 128      This field is valid only if special_addr_p is true.  Otherwise, this
 129      frame is considered to have a wildcard special address, i.e. one that
 130      matches every address value in frame comparisons.  */
 131   CORE_ADDR special_addr;
 132
 133   /* Flags to indicate the above fields have valid contents.  */
 134   unsigned int stack_addr_p : 1;
 135   unsigned int code_addr_p : 1;
 136   unsigned int special_addr_p : 1;
 137
 138   /* The inline depth of this frame.  A frame representing a "called"
 139      inlined function will have this set to a nonzero value.  */
 140   int inline_depth;
 141 };
 142
 143 /* Methods for constructing and comparing Frame IDs.  */
 144
 145 /* For convenience.  All fields are zero.  */
 146 extern const struct frame_id null_frame_id;
 147
 148 /* Flag to control debugging.  */
 149
 150 extern int frame_debug;
 151
 152 /* Construct a frame ID.  The first parameter is the frame's constant
 153    stack address (typically the outer-bound), and the second the
 154    frame's constant code address (typically the entry point).
 155    The special identifier address is set to indicate a wild card.  */
 156 extern struct frame_id frame_id_build (CORE_ADDR stack_addr,
 157                                        CORE_ADDR code_addr);
 158
 159 /* Construct a special frame ID.  The first parameter is the frame's constant
 160    stack address (typically the outer-bound), the second is the
 161    frame's constant code address (typically the entry point),
 162    and the third parameter is the frame's special identifier address. */
 163 extern struct frame_id frame_id_build_special (CORE_ADDR stack_addr,
 164                                                CORE_ADDR code_addr,
 165                                                CORE_ADDR special_addr);
 166
 167 /* Construct a wild card frame ID.  The parameter is the frame's constant
 168    stack address (typically the outer-bound).  The code address as well
 169    as the special identifier address are set to indicate wild cards.  */
 170 extern struct frame_id frame_id_build_wild (CORE_ADDR stack_addr);
 171
 172 /* Returns non-zero when L is a valid frame (a valid frame has a
 173    non-zero .base).  */
 174 extern int frame_id_p (struct frame_id l);
 175
 176 /* Returns non-zero when L is a valid frame representing an inlined
 177    function.  */
 178 extern int frame_id_inlined_p (struct frame_id l);
 179
 180 /* Returns non-zero when L and R identify the same frame, or, if
 181    either L or R have a zero .func, then the same frame base.  */
 182 extern int frame_id_eq (struct frame_id l, struct frame_id r);
 183
 184 /* Write the internal representation of a frame ID on the specified
 185    stream.  */
 186 extern void fprint_frame_id (struct ui_file *file, struct frame_id id);
 187
 188
 189 /* Frame types.  Some are real, some are signal trampolines, and some
 190    are completely artificial (dummy).  */
 191
 192 enum frame_type
 193 {
 194   /* A true stack frame, created by the target program during normal
 195      execution.  */
 196   NORMAL_FRAME,
 197   /* A fake frame, created by GDB when performing an inferior function
 198      call.  */
 199   DUMMY_FRAME,
 200   /* A frame representing an inlined function, associated with an
 201      upcoming (next, inner, younger) NORMAL_FRAME.  */
 202   INLINE_FRAME,
 203   /* In a signal handler, various OSs handle this in various ways.
 204      The main thing is that the frame may be far from normal.  */
 205   SIGTRAMP_FRAME,
 206   /* Sentinel or registers frame.  This frame obtains register values
 207      direct from the inferior's registers.  */
 208   SENTINEL_FRAME
 209 };
 210
 211 /* For every stopped thread, GDB tracks two frames: current and
 212    selected.  Current frame is the inner most frame of the selected
 213    thread.  Selected frame is the one being examined by the the GDB
 214    CLI (selected using `up', `down', ...).  The frames are created
 215    on-demand (via get_prev_frame()) and then held in a frame cache.  */
 216 /* FIXME: cagney/2002-11-28: Er, there is a lie here.  If you do the
 217    sequence: `thread 1; up; thread 2; thread 1' you lose thread 1's
 218    selected frame.  At present GDB only tracks the selected frame of
 219    the current thread.  But be warned, that might change.  */
 220 /* FIXME: cagney/2002-11-14: At any time, only one thread's selected
 221    and current frame can be active.  Switching threads causes gdb to
 222    discard all that cached frame information.  Ulgh!  Instead, current
 223    and selected frame should be bound to a thread.  */
 224
 225 /* On demand, create the inner most frame using information found in
 226    the inferior.  If the inner most frame can't be created, throw an
 227    error.  */
 228 extern struct frame_info *get_current_frame (void);
 229
 230 /* Does the current target interface have enough state to be able to
 231    query the current inferior for frame info, and is the inferior in a
 232    state where that is possible?  */
 233 extern int has_stack_frames (void);
 234
 235 /* Invalidates the frame cache (this function should have been called
 236    invalidate_cached_frames).
 237
 238    FIXME: cagney/2002-11-28: There should be two methods: one that
 239    reverts the thread's selected frame back to current frame (for when
 240    the inferior resumes) and one that does not (for when the user
 241    modifies the target invalidating the frame cache).  */
 242 extern void reinit_frame_cache (void);
 243
 244 /* On demand, create the selected frame and then return it.  If the
 245    selected frame can not be created, this function prints then throws
 246    an error.  When MESSAGE is non-NULL, use it for the error message,
 247    otherwize use a generic error message.  */
 248 /* FIXME: cagney/2002-11-28: At present, when there is no selected
 249    frame, this function always returns the current (inner most) frame.
 250    It should instead, when a thread has previously had its frame
 251    selected (but not resumed) and the frame cache invalidated, find
 252    and then return that thread's previously selected frame.  */
 253 extern struct frame_info *get_selected_frame (const char *message);
 254
 255 /* Select a specific frame.  NULL, apparently implies re-select the
 256    inner most frame.  */
 257 extern void select_frame (struct frame_info *);
 258
 259 /* Given a FRAME, return the next (more inner, younger) or previous
 260    (more outer, older) frame.  */
 261 extern struct frame_info *get_prev_frame (struct frame_info *);
 262 extern struct frame_info *get_next_frame (struct frame_info *);
 263
 264 /* Given a frame's ID, relocate the frame.  Returns NULL if the frame
 265    is not found.  */
 266 extern struct frame_info *frame_find_by_id (struct frame_id id);
 267
 268 /* Base attributes of a frame: */
 269
 270 /* The frame's `resume' address.  Where the program will resume in
 271    this frame.
 272
 273    This replaced: frame->pc; */
 274 extern CORE_ADDR get_frame_pc (struct frame_info *);
 275
 276 /* An address (not necessarily aligned to an instruction boundary)
 277    that falls within THIS frame's code block.
 278
 279    When a function call is the last statement in a block, the return
 280    address for the call may land at the start of the next block.
 281    Similarly, if a no-return function call is the last statement in
 282    the function, the return address may end up pointing beyond the
 283    function, and possibly at the start of the next function.
 284
 285    These methods make an allowance for this.  For call frames, this
 286    function returns the frame's PC-1 which "should" be an address in
 287    the frame's block.  */
 288
 289 extern CORE_ADDR get_frame_address_in_block (struct frame_info *this_frame);
 290
 291 /* The frame's inner-most bound.  AKA the stack-pointer.  Confusingly
 292    known as top-of-stack.  */
 293
 294 extern CORE_ADDR get_frame_sp (struct frame_info *);
 295
 296 /* Following on from the `resume' address.  Return the entry point
 297    address of the function containing that resume address, or zero if
 298    that function isn't known.  */
 299 extern CORE_ADDR get_frame_func (struct frame_info *fi);
 300
 301 /* Closely related to the resume address, various symbol table
 302    attributes that are determined by the PC.  Note that for a normal
 303    frame, the PC refers to the resume address after the return, and
 304    not the call instruction.  In such a case, the address is adjusted
 305    so that it (approximately) identifies the call site (and not the
 306    return site).
 307
 308    NOTE: cagney/2002-11-28: The frame cache could be used to cache the
 309    computed value.  Working on the assumption that the bottle-neck is
 310    in the single step code, and that code causes the frame cache to be
 311    constantly flushed, caching things in a frame is probably of little
 312    benefit.  As they say `show us the numbers'.
 313
 314    NOTE: cagney/2002-11-28: Plenty more where this one came from:
 315    find_frame_block(), find_frame_partial_function(),
 316    find_frame_symtab(), find_frame_function().  Each will need to be
 317    carefully considered to determine if the real intent was for it to
 318    apply to the PC or the adjusted PC.  */
 319 extern void find_frame_sal (struct frame_info *frame,
 320                             struct symtab_and_line *sal);
 321
 322 /* Set the current source and line to the location given by frame
 323    FRAME, if possible.  When CENTER is true, adjust so the relevant
 324    line is in the center of the next 'list'.  */
 325
 326 void set_current_sal_from_frame (struct frame_info *, int);
 327
 328 /* Return the frame base (what ever that is) (DEPRECATED).
 329
 330    Old code was trying to use this single method for two conflicting
 331    purposes.  Such code needs to be updated to use either of:
 332
 333    get_frame_id: A low level frame unique identifier, that consists of
 334    both a stack and a function address, that can be used to uniquely
 335    identify a frame.  This value is determined by the frame's
 336    low-level unwinder, the stack part [typically] being the
 337    top-of-stack of the previous frame, and the function part being the
 338    function's start address.  Since the correct identification of a
 339    frameless function requires both the a stack and function address,
 340    the old get_frame_base method was not sufficient.
 341
 342    get_frame_base_address: get_frame_locals_address:
 343    get_frame_args_address: A set of high-level debug-info dependant
 344    addresses that fall within the frame.  These addresses almost
 345    certainly will not match the stack address part of a frame ID (as
 346    returned by get_frame_base).
 347
 348    This replaced: frame->frame; */
 349
 350 extern CORE_ADDR get_frame_base (struct frame_info *);
 351
 352 /* Return the per-frame unique identifer.  Can be used to relocate a
 353    frame after a frame cache flush (and other similar operations).  If
 354    FI is NULL, return the null_frame_id.
 355
 356    NOTE: kettenis/20040508: These functions return a structure.  On
 357    platforms where structures are returned in static storage (vax,
 358    m68k), this may trigger compiler bugs in code like:
 359
 360    if (frame_id_eq (get_frame_id (l), get_frame_id (r)))
 361
 362    where the return value from the first get_frame_id (l) gets
 363    overwritten by the second get_frame_id (r).  Please avoid writing
 364    code like this.  Use code like:
 365
 366    struct frame_id id = get_frame_id (l);
 367    if (frame_id_eq (id, get_frame_id (r)))
 368
 369    instead, since that avoids the bug.  */
 370 extern struct frame_id get_frame_id (struct frame_info *fi);
 371 extern struct frame_id get_stack_frame_id (struct frame_info *fi);
 372 extern struct frame_id frame_unwind_caller_id (struct frame_info *next_frame);
 373
 374 /* Assuming that a frame is `normal', return its base-address, or 0 if
 375    the information isn't available.  NOTE: This address is really only
 376    meaningful to the frame's high-level debug info.  */
 377 extern CORE_ADDR get_frame_base_address (struct frame_info *);
 378
 379 /* Assuming that a frame is `normal', return the base-address of the
 380    local variables, or 0 if the information isn't available.  NOTE:
 381    This address is really only meaningful to the frame's high-level
 382    debug info.  Typically, the argument and locals share a single
 383    base-address.  */
 384 extern CORE_ADDR get_frame_locals_address (struct frame_info *);
 385
 386 /* Assuming that a frame is `normal', return the base-address of the
 387    parameter list, or 0 if that information isn't available.  NOTE:
 388    This address is really only meaningful to the frame's high-level
 389    debug info.  Typically, the argument and locals share a single
 390    base-address.  */
 391 extern CORE_ADDR get_frame_args_address (struct frame_info *);
 392
 393 /* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
 394    for an invalid frame).  */
 395 extern int frame_relative_level (struct frame_info *fi);
 396
 397 /* Return the frame's type.  */
 398
 399 extern enum frame_type get_frame_type (struct frame_info *);
 400
 401 /* For frames where we can not unwind further, describe why.  */
 402
 403 enum unwind_stop_reason
 404   {
 405     /* No particular reason; either we haven't tried unwinding yet,
 406        or we didn't fail.  */
 407     UNWIND_NO_REASON,
 408
 409     /* The previous frame's analyzer returns an invalid result
 410        from this_id.
 411
 412        FIXME drow/2006-08-16: This is how GDB used to indicate end of
 413        stack.  We should migrate to a model where frames always have a
 414        valid ID, and this becomes not just an error but an internal
 415        error.  But that's a project for another day.  */
 416     UNWIND_NULL_ID,
 417
 418     /* All the conditions after this point are considered errors;
 419        abnormal stack termination.  If a backtrace stops for one
 420        of these reasons, we'll let the user know.  This marker
 421        is not a valid stop reason.  */
 422     UNWIND_FIRST_ERROR,
 423
 424     /* This frame ID looks like it ought to belong to a NEXT frame,
 425        but we got it for a PREV frame.  Normally, this is a sign of
 426        unwinder failure.  It could also indicate stack corruption.  */
 427     UNWIND_INNER_ID,
 428
 429     /* This frame has the same ID as the previous one.  That means
 430        that unwinding further would almost certainly give us another
 431        frame with exactly the same ID, so break the chain.  Normally,
 432        this is a sign of unwinder failure.  It could also indicate
 433        stack corruption.  */
 434     UNWIND_SAME_ID,
 435
 436     /* The frame unwinder didn't find any saved PC, but we needed
 437        one to unwind further.  */
 438     UNWIND_NO_SAVED_PC,
 439   };
 440
 441 /* Return the reason why we can't unwind past this frame.  */
 442
 443 enum unwind_stop_reason get_frame_unwind_stop_reason (struct frame_info *);
 444
 445 /* Translate a reason code to an informative string.  */
 446
 447 const char *frame_stop_reason_string (enum unwind_stop_reason);
 448
 449 /* Unwind the stack frame so that the value of REGNUM, in the previous
 450    (up, older) frame is returned.  If VALUEP is NULL, don't
 451    fetch/compute the value.  Instead just return the location of the
 452    value.  */
 453 extern void frame_register_unwind (struct frame_info *frame, int regnum,
 454                                    int *optimizedp, enum lval_type *lvalp,
 455                                    CORE_ADDR *addrp, int *realnump,
 456                                    gdb_byte *valuep);
 457
 458 /* Fetch a register from this, or unwind a register from the next
 459    frame.  Note that the get_frame methods are wrappers to
 460    frame->next->unwind.  They all [potentially] throw an error if the
 461    fetch fails.  The value methods never return NULL, but usually
 462    do return a lazy value.  */
 463
 464 extern void frame_unwind_register (struct frame_info *frame,
 465                                    int regnum, gdb_byte *buf);
 466 extern void get_frame_register (struct frame_info *frame,
 467                                 int regnum, gdb_byte *buf);
 468
 469 struct value *frame_unwind_register_value (struct frame_info *frame,
 470                                            int regnum);
 471 struct value *get_frame_register_value (struct frame_info *frame,
 472                                         int regnum);
 473
 474 extern LONGEST frame_unwind_register_signed (struct frame_info *frame,
 475                                              int regnum);
 476 extern LONGEST get_frame_register_signed (struct frame_info *frame,
 477                                           int regnum);
 478 extern ULONGEST frame_unwind_register_unsigned (struct frame_info *frame,
 479                                                int regnum);
 480 extern ULONGEST get_frame_register_unsigned (struct frame_info *frame,
 481                                              int regnum);
 482
 483
 484 /* Get the value of the register that belongs to this FRAME.  This
 485    function is a wrapper to the call sequence ``frame_register_unwind
 486    (get_next_frame (FRAME))''.  As per frame_register_unwind(), if
 487    VALUEP is NULL, the registers value is not fetched/computed.  */
 488
 489 extern void frame_register (struct frame_info *frame, int regnum,
 490                             int *optimizedp, enum lval_type *lvalp,
 491                             CORE_ADDR *addrp, int *realnump,
 492                             gdb_byte *valuep);
 493
 494 /* The reverse.  Store a register value relative to the specified
 495    frame.  Note: this call makes the frame's state undefined.  The
 496    register and frame caches must be flushed.  */
 497 extern void put_frame_register (struct frame_info *frame, int regnum,
 498                                 const gdb_byte *buf);
 499
 500 /* Read LEN bytes from one or multiple registers starting with REGNUM
 501    in frame FRAME, starting at OFFSET, into BUF.  */
 502 extern int get_frame_register_bytes (struct frame_info *frame, int regnum,
 503                                      CORE_ADDR offset, int len,
 504                                      gdb_byte *myaddr);
 505
 506 /* Write LEN bytes to one or multiple registers starting with REGNUM
 507    in frame FRAME, starting at OFFSET, into BUF.  */
 508 extern void put_frame_register_bytes (struct frame_info *frame, int regnum,
 509                                       CORE_ADDR offset, int len,
 510                                       const gdb_byte *myaddr);
 511
 512 /* Unwind the PC.  Strictly speaking return the resume address of the
 513    calling frame.  For GDB, `pc' is the resume address and not a
 514    specific register.  */
 515
 516 extern CORE_ADDR frame_unwind_caller_pc (struct frame_info *frame);
 517
 518 /* Discard the specified frame.  Restoring the registers to the state
 519    of the caller.  */
 520 extern void frame_pop (struct frame_info *frame);
 521
 522 /* Return memory from the specified frame.  A frame knows its thread /
 523    LWP and hence can find its way down to a target.  The assumption
 524    here is that the current and previous frame share a common address
 525    space.
 526
 527    If the memory read fails, these methods throw an error.
 528
 529    NOTE: cagney/2003-06-03: Should there be unwind versions of these
 530    methods?  That isn't clear.  Can code, for instance, assume that
 531    this and the previous frame's memory or architecture are identical?
 532    If architecture / memory changes are always separated by special
 533    adaptor frames this should be ok.  */
 534
 535 extern void get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
 536                               gdb_byte *buf, int len);
 537 extern LONGEST get_frame_memory_signed (struct frame_info *this_frame,
 538                                         CORE_ADDR memaddr, int len);
 539 extern ULONGEST get_frame_memory_unsigned (struct frame_info *this_frame,
 540                                            CORE_ADDR memaddr, int len);
 541
 542 /* Same as above, but return non-zero when the entire memory read
 543    succeeds, zero otherwize.  */
 544 extern int safe_frame_unwind_memory (struct frame_info *this_frame,
 545                                      CORE_ADDR addr, gdb_byte *buf, int len);
 546
 547 /* Return this frame's architecture.  */
 548
 549 extern struct gdbarch *get_frame_arch (struct frame_info *this_frame);
 550
 551
 552 /* Values for the source flag to be used in print_frame_info_base().  */
 553 enum print_what
 554   {
 555     /* Print only the source line, like in stepi. */
 556     SRC_LINE = -1,
 557     /* Print only the location, i.e. level, address (sometimes)
 558        function, args, file, line, line num. */
 559     LOCATION,
 560     /* Print both of the above. */
 561     SRC_AND_LOC,
 562     /* Print location only, but always include the address. */
 563     LOC_AND_ADDRESS
 564   };
 565
 566 /* Allocate zero initialized memory from the frame cache obstack.
 567    Appendices to the frame info (such as the unwind cache) should
 568    allocate memory using this method.  */
 569
 570 extern void *frame_obstack_zalloc (unsigned long size);
 571 #define FRAME_OBSTACK_ZALLOC(TYPE) ((TYPE *) frame_obstack_zalloc (sizeof (TYPE)))
 572 #define FRAME_OBSTACK_CALLOC(NUMBER,TYPE) ((TYPE *) frame_obstack_zalloc ((NUMBER) * sizeof (TYPE)))
 573
 574 /* Create a regcache, and copy the frame's registers into it.  */
 575 struct regcache *frame_save_as_regcache (struct frame_info *this_frame);
 576
 577 extern struct block *get_frame_block (struct frame_info *,
 578                                       CORE_ADDR *addr_in_block);
 579
 580 /* Return the `struct block' that belongs to the selected thread's
 581    selected frame.  If the inferior has no state, return NULL.
 582
 583    NOTE: cagney/2002-11-29:
 584
 585    No state?  Does the inferior have any execution state (a core file
 586    does, an executable does not).  At present the code tests
 587    `target_has_stack' but I'm left wondering if it should test
 588    `target_has_registers' or, even, a merged target_has_state.
 589
 590    Should it look at the most recently specified SAL?  If the target
 591    has no state, should this function try to extract a block from the
 592    most recently selected SAL?  That way `list foo' would give it some
 593    sort of reference point.  Then again, perhaps that would confuse
 594    things.
 595
 596    Calls to this function can be broken down into two categories: Code
 597    that uses the selected block as an additional, but optional, data
 598    point; Code that uses the selected block as a prop, when it should
 599    have the relevant frame/block/pc explicitly passed in.
 600
 601    The latter can be eliminated by correctly parameterizing the code,
 602    the former though is more interesting.  Per the "address" command,
 603    it occurs in the CLI code and makes it possible for commands to
 604    work, even when the inferior has no state.  */
 605
 606 extern struct block *get_selected_block (CORE_ADDR *addr_in_block);
 607
 608 extern struct symbol *get_frame_function (struct frame_info *);
 609
 610 extern CORE_ADDR get_pc_function_start (CORE_ADDR);
 611
 612 extern struct frame_info *find_relative_frame (struct frame_info *, int *);
 613
 614 extern void show_and_print_stack_frame (struct frame_info *fi, int print_level,
 615                                         enum print_what print_what);
 616
 617 extern void print_stack_frame (struct frame_info *, int print_level,
 618                                enum print_what print_what);
 619
 620 extern void print_frame_info (struct frame_info *, int print_level,
 621                               enum print_what print_what, int args);
 622
 623 extern struct frame_info *block_innermost_frame (struct block *);
 624
 625 extern int deprecated_pc_in_call_dummy (struct gdbarch *gdbarch, CORE_ADDR pc);
 626
 627 /* FIXME: cagney/2003-02-02: Should be deprecated or replaced with a
 628    function called get_frame_register_p().  This slightly weird (and
 629    older) variant of get_frame_register() returns zero (indicating the
 630    register is unavailable) if either: the register isn't cached; or
 631    the register has been optimized out.  Problem is, neither check is
 632    exactly correct.  A register can't be optimized out (it may not
 633    have been saved as part of a function call); The fact that a
 634    register isn't in the register cache doesn't mean that the register
 635    isn't available (it could have been fetched from memory).  */
 636
 637 extern int frame_register_read (struct frame_info *frame, int regnum,
 638                                 gdb_byte *buf);
 639
 640 /* From stack.c.  */
 641 extern void args_info (char *, int);
 642
 643 extern void locals_info (char *, int);
 644
 645 extern void (*deprecated_selected_frame_level_changed_hook) (int);
 646
 647 extern void return_command (char *, int);
 648
 649 /* Set FRAME's unwinder temporarily, so that we can call a sniffer.
 650    Return a cleanup which should be called if unwinding fails, and
 651    discarded if it succeeds.  */
 652
 653 struct cleanup *frame_prepare_for_sniffer (struct frame_info *frame,
 654                                            const struct frame_unwind *unwind);
 655
 656 /* Notes (cagney/2002-11-27, drow/2003-09-06):
 657
 658    You might think that calls to this function can simply be replaced by a
 659    call to get_selected_frame().
 660
 661    Unfortunately, it isn't that easy.
 662
 663    The relevant code needs to be audited to determine if it is
 664    possible (or practical) to instead pass the applicable frame in as a
 665    parameter.  For instance, DEPRECATED_DO_REGISTERS_INFO() relied on
 666    the deprecated_selected_frame global, while its replacement,
 667    PRINT_REGISTERS_INFO(), is parameterized with the selected frame.
 668    The only real exceptions occur at the edge (in the CLI code) where
 669    user commands need to pick up the selected frame before proceeding.
 670
 671    There are also some functions called with a NULL frame meaning either "the
 672    program is not running" or "use the selected frame".
 673
 674    This is important.  GDB is trying to stamp out the hack:
 675
 676    saved_frame = deprecated_safe_get_selected_frame ();
 677    select_frame (...);
 678    hack_using_global_selected_frame ();
 679    select_frame (saved_frame);
 680
 681    Take care!
 682
 683    This function calls get_selected_frame if the inferior should have a
 684    frame, or returns NULL otherwise.  */
 685
 686 extern struct frame_info *deprecated_safe_get_selected_frame (void);
 687
 688 /* Create a frame using the specified BASE and PC.  */
 689
 690 extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc);
 691
 692 #endif /* !defined (FRAME_H)  */