gdb/frame.h

   1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2014 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 /* Status of a given frame's stack.  */
  80
  81 enum frame_id_stack_status
  82 {
  83   /* Stack address is invalid.  E.g., this frame is the outermost
  84      (i.e., _start), and the stack hasn't been setup yet.  */
  85   FID_STACK_INVALID = 0,
  86
  87   /* Stack address is valid, and is found in the stack_addr field.  */
  88   FID_STACK_VALID = 1,
  89
  90   /* Stack address is unavailable.  I.e., there's a valid stack, but
  91      we don't know where it is (because memory or registers we'd
  92      compute it from were not collected).  */
  93   FID_STACK_UNAVAILABLE = -1
  94 };
  95
  96 /* The frame object.  */
  97
  98 struct frame_info;
  99
 100 /* The frame object's ID.  This provides a per-frame unique identifier
 101    that can be used to relocate a `struct frame_info' after a target
 102    resume or a frame cache destruct.  It of course assumes that the
 103    inferior hasn't unwound the stack past that frame.  */
 104
 105 struct frame_id
 106 {
 107   /* The frame's stack address.  This shall be constant through out
 108      the lifetime of a frame.  Note that this requirement applies to
 109      not just the function body, but also the prologue and (in theory
 110      at least) the epilogue.  Since that value needs to fall either on
 111      the boundary, or within the frame's address range, the frame's
 112      outer-most address (the inner-most address of the previous frame)
 113      is used.  Watch out for all the legacy targets that still use the
 114      function pointer register or stack pointer register.  They are
 115      wrong.
 116
 117      This field is valid only if frame_id.stack_status is
 118      FID_STACK_VALID.  It will be 0 for other
 119      FID_STACK_... statuses.  */
 120   CORE_ADDR stack_addr;
 121
 122   /* The frame's code address.  This shall be constant through out the
 123      lifetime of the frame.  While the PC (a.k.a. resume address)
 124      changes as the function is executed, this code address cannot.
 125      Typically, it is set to the address of the entry point of the
 126      frame's function (as returned by get_frame_func).
 127
 128      For inlined functions (INLINE_DEPTH != 0), this is the address of
 129      the first executed instruction in the block corresponding to the
 130      inlined function.
 131
 132      This field is valid only if code_addr_p is true.  Otherwise, this
 133      frame is considered to have a wildcard code address, i.e. one that
 134      matches every address value in frame comparisons.  */
 135   CORE_ADDR code_addr;
 136
 137   /* The frame's special address.  This shall be constant through out the
 138      lifetime of the frame.  This is used for architectures that may have
 139      frames that do not change the stack but are still distinct and have
 140      some form of distinct identifier (e.g. the ia64 which uses a 2nd
 141      stack for registers).  This field is treated as unordered - i.e. will
 142      not be used in frame ordering comparisons.
 143
 144      This field is valid only if special_addr_p is true.  Otherwise, this
 145      frame is considered to have a wildcard special address, i.e. one that
 146      matches every address value in frame comparisons.  */
 147   CORE_ADDR special_addr;
 148
 149   /* Flags to indicate the above fields have valid contents.  */
 150   ENUM_BITFIELD(frame_id_stack_status) stack_status : 2;
 151   unsigned int code_addr_p : 1;
 152   unsigned int special_addr_p : 1;
 153
 154   /* It is non-zero for a frame made up by GDB without stack data
 155      representation in inferior, such as INLINE_FRAME or TAILCALL_FRAME.
 156      Caller of inlined function will have it zero, each more inner called frame
 157      will have it increasingly one, two etc.  Similarly for TAILCALL_FRAME.  */
 158   int artificial_depth;
 159 };
 160
 161 /* Methods for constructing and comparing Frame IDs.  */
 162
 163 /* For convenience.  All fields are zero.  This means "there is no frame".  */
 164 extern const struct frame_id null_frame_id;
 165
 166 /* This means "there is no frame ID, but there is a frame".  It should be
 167    replaced by best-effort frame IDs for the outermost frame, somehow.
 168    The implementation is only special_addr_p set.  */
 169 extern const struct frame_id outer_frame_id;
 170
 171 /* Flag to control debugging.  */
 172
 173 extern unsigned int frame_debug;
 174
 175 /* Construct a frame ID.  The first parameter is the frame's constant
 176    stack address (typically the outer-bound), and the second the
 177    frame's constant code address (typically the entry point).
 178    The special identifier address is set to indicate a wild card.  */
 179 extern struct frame_id frame_id_build (CORE_ADDR stack_addr,
 180                                        CORE_ADDR code_addr);
 181
 182 /* Construct a special frame ID.  The first parameter is the frame's constant
 183    stack address (typically the outer-bound), the second is the
 184    frame's constant code address (typically the entry point),
 185    and the third parameter is the frame's special identifier address.  */
 186 extern struct frame_id frame_id_build_special (CORE_ADDR stack_addr,
 187                                                CORE_ADDR code_addr,
 188                                                CORE_ADDR special_addr);
 189
 190 /* Construct a frame ID representing a frame where the stack address
 191    exists, but is unavailable.  CODE_ADDR is the frame's constant code
 192    address (typically the entry point).  The special identifier
 193    address is set to indicate a wild card.  */
 194 extern struct frame_id frame_id_build_unavailable_stack (CORE_ADDR code_addr);
 195
 196 /* Construct a frame ID representing a frame where the stack address
 197    exists, but is unavailable.  CODE_ADDR is the frame's constant code
 198    address (typically the entry point).  SPECIAL_ADDR is the special
 199    identifier address.  */
 200 extern struct frame_id
 201   frame_id_build_unavailable_stack_special (CORE_ADDR code_addr,
 202                                             CORE_ADDR special_addr);
 203
 204 /* Construct a wild card frame ID.  The parameter is the frame's constant
 205    stack address (typically the outer-bound).  The code address as well
 206    as the special identifier address are set to indicate wild cards.  */
 207 extern struct frame_id frame_id_build_wild (CORE_ADDR stack_addr);
 208
 209 /* Returns non-zero when L is a valid frame (a valid frame has a
 210    non-zero .base).  The outermost frame is valid even without an
 211    ID.  */
 212 extern int frame_id_p (struct frame_id l);
 213
 214 /* Returns non-zero when L is a valid frame representing a frame made up by GDB
 215    without stack data representation in inferior, such as INLINE_FRAME or
 216    TAILCALL_FRAME.  */
 217 extern int frame_id_artificial_p (struct frame_id l);
 218
 219 /* Returns non-zero when L and R identify the same frame, or, if
 220    either L or R have a zero .func, then the same frame base.  */
 221 extern int frame_id_eq (struct frame_id l, struct frame_id r);
 222
 223 /* Write the internal representation of a frame ID on the specified
 224    stream.  */
 225 extern void fprint_frame_id (struct ui_file *file, struct frame_id id);
 226
 227
 228 /* Frame types.  Some are real, some are signal trampolines, and some
 229    are completely artificial (dummy).  */
 230
 231 enum frame_type
 232 {
 233   /* A true stack frame, created by the target program during normal
 234      execution.  */
 235   NORMAL_FRAME,
 236   /* A fake frame, created by GDB when performing an inferior function
 237      call.  */
 238   DUMMY_FRAME,
 239   /* A frame representing an inlined function, associated with an
 240      upcoming (prev, outer, older) NORMAL_FRAME.  */
 241   INLINE_FRAME,
 242   /* A virtual frame of a tail call - see dwarf2_tailcall_frame_unwind.  */
 243   TAILCALL_FRAME,
 244   /* In a signal handler, various OSs handle this in various ways.
 245      The main thing is that the frame may be far from normal.  */
 246   SIGTRAMP_FRAME,
 247   /* Fake frame representing a cross-architecture call.  */
 248   ARCH_FRAME,
 249   /* Sentinel or registers frame.  This frame obtains register values
 250      direct from the inferior's registers.  */
 251   SENTINEL_FRAME
 252 };
 253
 254 /* For every stopped thread, GDB tracks two frames: current and
 255    selected.  Current frame is the inner most frame of the selected
 256    thread.  Selected frame is the one being examined by the GDB
 257    CLI (selected using `up', `down', ...).  The frames are created
 258    on-demand (via get_prev_frame()) and then held in a frame cache.  */
 259 /* FIXME: cagney/2002-11-28: Er, there is a lie here.  If you do the
 260    sequence: `thread 1; up; thread 2; thread 1' you lose thread 1's
 261    selected frame.  At present GDB only tracks the selected frame of
 262    the current thread.  But be warned, that might change.  */
 263 /* FIXME: cagney/2002-11-14: At any time, only one thread's selected
 264    and current frame can be active.  Switching threads causes gdb to
 265    discard all that cached frame information.  Ulgh!  Instead, current
 266    and selected frame should be bound to a thread.  */
 267
 268 /* On demand, create the inner most frame using information found in
 269    the inferior.  If the inner most frame can't be created, throw an
 270    error.  */
 271 extern struct frame_info *get_current_frame (void);
 272
 273 /* Does the current target interface have enough state to be able to
 274    query the current inferior for frame info, and is the inferior in a
 275    state where that is possible?  */
 276 extern int has_stack_frames (void);
 277
 278 /* Invalidates the frame cache (this function should have been called
 279    invalidate_cached_frames).
 280
 281    FIXME: cagney/2002-11-28: There should be two methods: one that
 282    reverts the thread's selected frame back to current frame (for when
 283    the inferior resumes) and one that does not (for when the user
 284    modifies the target invalidating the frame cache).  */
 285 extern void reinit_frame_cache (void);
 286
 287 /* On demand, create the selected frame and then return it.  If the
 288    selected frame can not be created, this function prints then throws
 289    an error.  When MESSAGE is non-NULL, use it for the error message,
 290    otherwize use a generic error message.  */
 291 /* FIXME: cagney/2002-11-28: At present, when there is no selected
 292    frame, this function always returns the current (inner most) frame.
 293    It should instead, when a thread has previously had its frame
 294    selected (but not resumed) and the frame cache invalidated, find
 295    and then return that thread's previously selected frame.  */
 296 extern struct frame_info *get_selected_frame (const char *message);
 297
 298 /* If there is a selected frame, return it.  Otherwise, return NULL.  */
 299 extern struct frame_info *get_selected_frame_if_set (void);
 300
 301 /* Select a specific frame.  NULL, apparently implies re-select the
 302    inner most frame.  */
 303 extern void select_frame (struct frame_info *);
 304
 305 /* Given a FRAME, return the next (more inner, younger) or previous
 306    (more outer, older) frame.  */
 307 extern struct frame_info *get_prev_frame (struct frame_info *);
 308 extern struct frame_info *get_next_frame (struct frame_info *);
 309
 310 /* Return a "struct frame_info" corresponding to the frame that called
 311    THIS_FRAME.  Returns NULL if there is no such frame.
 312
 313    Unlike get_prev_frame, this function always tries to unwind the
 314    frame.  */
 315 extern struct frame_info *get_prev_frame_always (struct frame_info *);
 316
 317 /* Given a frame's ID, relocate the frame.  Returns NULL if the frame
 318    is not found.  */
 319 extern struct frame_info *frame_find_by_id (struct frame_id id);
 320
 321 /* Base attributes of a frame: */
 322
 323 /* The frame's `resume' address.  Where the program will resume in
 324    this frame.
 325
 326    This replaced: frame->pc; */
 327 extern CORE_ADDR get_frame_pc (struct frame_info *);
 328
 329 /* Same as get_frame_pc, but return a boolean indication of whether
 330    the PC is actually available, instead of throwing an error.  */
 331
 332 extern int get_frame_pc_if_available (struct frame_info *frame,
 333                                       CORE_ADDR *pc);
 334
 335 /* An address (not necessarily aligned to an instruction boundary)
 336    that falls within THIS frame's code block.
 337
 338    When a function call is the last statement in a block, the return
 339    address for the call may land at the start of the next block.
 340    Similarly, if a no-return function call is the last statement in
 341    the function, the return address may end up pointing beyond the
 342    function, and possibly at the start of the next function.
 343
 344    These methods make an allowance for this.  For call frames, this
 345    function returns the frame's PC-1 which "should" be an address in
 346    the frame's block.  */
 347
 348 extern CORE_ADDR get_frame_address_in_block (struct frame_info *this_frame);
 349
 350 /* Same as get_frame_address_in_block, but returns a boolean
 351    indication of whether the frame address is determinable (when the
 352    PC is unavailable, it will not be), instead of possibly throwing an
 353    error trying to read an unavailable PC.  */
 354
 355 extern int
 356   get_frame_address_in_block_if_available (struct frame_info *this_frame,
 357                                            CORE_ADDR *pc);
 358
 359 /* The frame's inner-most bound.  AKA the stack-pointer.  Confusingly
 360    known as top-of-stack.  */
 361
 362 extern CORE_ADDR get_frame_sp (struct frame_info *);
 363
 364 /* Following on from the `resume' address.  Return the entry point
 365    address of the function containing that resume address, or zero if
 366    that function isn't known.  */
 367 extern CORE_ADDR get_frame_func (struct frame_info *fi);
 368
 369 /* Same as get_frame_func, but returns a boolean indication of whether
 370    the frame function is determinable (when the PC is unavailable, it
 371    will not be), instead of possibly throwing an error trying to read
 372    an unavailable PC.  */
 373
 374 extern int get_frame_func_if_available (struct frame_info *fi, CORE_ADDR *);
 375
 376 /* Closely related to the resume address, various symbol table
 377    attributes that are determined by the PC.  Note that for a normal
 378    frame, the PC refers to the resume address after the return, and
 379    not the call instruction.  In such a case, the address is adjusted
 380    so that it (approximately) identifies the call site (and not the
 381    return site).
 382
 383    NOTE: cagney/2002-11-28: The frame cache could be used to cache the
 384    computed value.  Working on the assumption that the bottle-neck is
 385    in the single step code, and that code causes the frame cache to be
 386    constantly flushed, caching things in a frame is probably of little
 387    benefit.  As they say `show us the numbers'.
 388
 389    NOTE: cagney/2002-11-28: Plenty more where this one came from:
 390    find_frame_block(), find_frame_partial_function(),
 391    find_frame_symtab(), find_frame_function().  Each will need to be
 392    carefully considered to determine if the real intent was for it to
 393    apply to the PC or the adjusted PC.  */
 394 extern void find_frame_sal (struct frame_info *frame,
 395                             struct symtab_and_line *sal);
 396
 397 /* Set the current source and line to the location given by frame
 398    FRAME, if possible.  When CENTER is true, adjust so the relevant
 399    line is in the center of the next 'list'.  */
 400
 401 void set_current_sal_from_frame (struct frame_info *, int);
 402
 403 /* Return the frame base (what ever that is) (DEPRECATED).
 404
 405    Old code was trying to use this single method for two conflicting
 406    purposes.  Such code needs to be updated to use either of:
 407
 408    get_frame_id: A low level frame unique identifier, that consists of
 409    both a stack and a function address, that can be used to uniquely
 410    identify a frame.  This value is determined by the frame's
 411    low-level unwinder, the stack part [typically] being the
 412    top-of-stack of the previous frame, and the function part being the
 413    function's start address.  Since the correct identification of a
 414    frameless function requires both a stack and function address,
 415    the old get_frame_base method was not sufficient.
 416
 417    get_frame_base_address: get_frame_locals_address:
 418    get_frame_args_address: A set of high-level debug-info dependant
 419    addresses that fall within the frame.  These addresses almost
 420    certainly will not match the stack address part of a frame ID (as
 421    returned by get_frame_base).
 422
 423    This replaced: frame->frame; */
 424
 425 extern CORE_ADDR get_frame_base (struct frame_info *);
 426
 427 /* Return the per-frame unique identifer.  Can be used to relocate a
 428    frame after a frame cache flush (and other similar operations).  If
 429    FI is NULL, return the null_frame_id.
 430
 431    NOTE: kettenis/20040508: These functions return a structure.  On
 432    platforms where structures are returned in static storage (vax,
 433    m68k), this may trigger compiler bugs in code like:
 434
 435    if (frame_id_eq (get_frame_id (l), get_frame_id (r)))
 436
 437    where the return value from the first get_frame_id (l) gets
 438    overwritten by the second get_frame_id (r).  Please avoid writing
 439    code like this.  Use code like:
 440
 441    struct frame_id id = get_frame_id (l);
 442    if (frame_id_eq (id, get_frame_id (r)))
 443
 444    instead, since that avoids the bug.  */
 445 extern struct frame_id get_frame_id (struct frame_info *fi);
 446 extern struct frame_id get_stack_frame_id (struct frame_info *fi);
 447 extern struct frame_id frame_unwind_caller_id (struct frame_info *next_frame);
 448
 449 /* Assuming that a frame is `normal', return its base-address, or 0 if
 450    the information isn't available.  NOTE: This address is really only
 451    meaningful to the frame's high-level debug info.  */
 452 extern CORE_ADDR get_frame_base_address (struct frame_info *);
 453
 454 /* Assuming that a frame is `normal', return the base-address of the
 455    local variables, or 0 if the information isn't available.  NOTE:
 456    This address is really only meaningful to the frame's high-level
 457    debug info.  Typically, the argument and locals share a single
 458    base-address.  */
 459 extern CORE_ADDR get_frame_locals_address (struct frame_info *);
 460
 461 /* Assuming that a frame is `normal', return the base-address of the
 462    parameter list, or 0 if that information isn't available.  NOTE:
 463    This address is really only meaningful to the frame's high-level
 464    debug info.  Typically, the argument and locals share a single
 465    base-address.  */
 466 extern CORE_ADDR get_frame_args_address (struct frame_info *);
 467
 468 /* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
 469    for an invalid frame).  */
 470 extern int frame_relative_level (struct frame_info *fi);
 471
 472 /* Return the frame's type.  */
 473
 474 extern enum frame_type get_frame_type (struct frame_info *);
 475
 476 /* Return the frame's program space.  */
 477 extern struct program_space *get_frame_program_space (struct frame_info *);
 478
 479 /* Unwind THIS frame's program space from the NEXT frame.  */
 480 extern struct program_space *frame_unwind_program_space (struct frame_info *);
 481
 482 /* Return the frame's address space.  */
 483 extern struct address_space *get_frame_address_space (struct frame_info *);
 484
 485 /* For frames where we can not unwind further, describe why.  */
 486
 487 enum unwind_stop_reason
 488   {
 489 #define SET(name, description) name,
 490 #define FIRST_ENTRY(name) UNWIND_FIRST = name,
 491 #define LAST_ENTRY(name) UNWIND_LAST = name,
 492 #define FIRST_ERROR(name) UNWIND_FIRST_ERROR = name,
 493
 494 #include "unwind_stop_reasons.def"
 495 #undef SET
 496 #undef FIRST_ENTRY
 497 #undef LAST_ENTRY
 498 #undef FIRST_ERROR
 499   };
 500
 501 /* Return the reason why we can't unwind past this frame.  */
 502
 503 enum unwind_stop_reason get_frame_unwind_stop_reason (struct frame_info *);
 504
 505 /* Translate a reason code to an informative string.  */
 506
 507 const char *frame_stop_reason_string (enum unwind_stop_reason);
 508
 509 /* Unwind the stack frame so that the value of REGNUM, in the previous
 510    (up, older) frame is returned.  If VALUEP is NULL, don't
 511    fetch/compute the value.  Instead just return the location of the
 512    value.  */
 513 extern void frame_register_unwind (struct frame_info *frame, int regnum,
 514                                    int *optimizedp, int *unavailablep,
 515                                    enum lval_type *lvalp,
 516                                    CORE_ADDR *addrp, int *realnump,
 517                                    gdb_byte *valuep);
 518
 519 /* Fetch a register from this, or unwind a register from the next
 520    frame.  Note that the get_frame methods are wrappers to
 521    frame->next->unwind.  They all [potentially] throw an error if the
 522    fetch fails.  The value methods never return NULL, but usually
 523    do return a lazy value.  */
 524
 525 extern void frame_unwind_register (struct frame_info *frame,
 526                                    int regnum, gdb_byte *buf);
 527 extern void get_frame_register (struct frame_info *frame,
 528                                 int regnum, gdb_byte *buf);
 529
 530 struct value *frame_unwind_register_value (struct frame_info *frame,
 531                                            int regnum);
 532 struct value *get_frame_register_value (struct frame_info *frame,
 533                                         int regnum);
 534
 535 extern LONGEST frame_unwind_register_signed (struct frame_info *frame,
 536                                              int regnum);
 537 extern LONGEST get_frame_register_signed (struct frame_info *frame,
 538                                           int regnum);
 539 extern ULONGEST frame_unwind_register_unsigned (struct frame_info *frame,
 540                                                int regnum);
 541 extern ULONGEST get_frame_register_unsigned (struct frame_info *frame,
 542                                              int regnum);
 543
 544 /* Read a register from this, or unwind a register from the next
 545    frame.  Note that the read_frame methods are wrappers to
 546    get_frame_register_value, that do not throw if the result is
 547    optimized out or unavailable.  */
 548
 549 extern int read_frame_register_unsigned (struct frame_info *frame,
 550                                          int regnum, ULONGEST *val);
 551
 552 /* Get the value of the register that belongs to this FRAME.  This
 553    function is a wrapper to the call sequence ``frame_register_unwind
 554    (get_next_frame (FRAME))''.  As per frame_register_unwind(), if
 555    VALUEP is NULL, the registers value is not fetched/computed.  */
 556
 557 extern void frame_register (struct frame_info *frame, int regnum,
 558                             int *optimizedp, int *unavailablep,
 559                             enum lval_type *lvalp,
 560                             CORE_ADDR *addrp, int *realnump,
 561                             gdb_byte *valuep);
 562
 563 /* The reverse.  Store a register value relative to the specified
 564    frame.  Note: this call makes the frame's state undefined.  The
 565    register and frame caches must be flushed.  */
 566 extern void put_frame_register (struct frame_info *frame, int regnum,
 567                                 const gdb_byte *buf);
 568
 569 /* Read LEN bytes from one or multiple registers starting with REGNUM
 570    in frame FRAME, starting at OFFSET, into BUF.  If the register
 571    contents are optimized out or unavailable, set *OPTIMIZEDP,
 572    *UNAVAILABLEP accordingly.  */
 573 extern int get_frame_register_bytes (struct frame_info *frame, int regnum,
 574                                      CORE_ADDR offset, int len,
 575                                      gdb_byte *myaddr,
 576                                      int *optimizedp, int *unavailablep);
 577
 578 /* Write LEN bytes to one or multiple registers starting with REGNUM
 579    in frame FRAME, starting at OFFSET, into BUF.  */
 580 extern void put_frame_register_bytes (struct frame_info *frame, int regnum,
 581                                       CORE_ADDR offset, int len,
 582                                       const gdb_byte *myaddr);
 583
 584 /* Unwind the PC.  Strictly speaking return the resume address of the
 585    calling frame.  For GDB, `pc' is the resume address and not a
 586    specific register.  */
 587
 588 extern CORE_ADDR frame_unwind_caller_pc (struct frame_info *frame);
 589
 590 /* Discard the specified frame.  Restoring the registers to the state
 591    of the caller.  */
 592 extern void frame_pop (struct frame_info *frame);
 593
 594 /* Return memory from the specified frame.  A frame knows its thread /
 595    LWP and hence can find its way down to a target.  The assumption
 596    here is that the current and previous frame share a common address
 597    space.
 598
 599    If the memory read fails, these methods throw an error.
 600
 601    NOTE: cagney/2003-06-03: Should there be unwind versions of these
 602    methods?  That isn't clear.  Can code, for instance, assume that
 603    this and the previous frame's memory or architecture are identical?
 604    If architecture / memory changes are always separated by special
 605    adaptor frames this should be ok.  */
 606
 607 extern void get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
 608                               gdb_byte *buf, int len);
 609 extern LONGEST get_frame_memory_signed (struct frame_info *this_frame,
 610                                         CORE_ADDR memaddr, int len);
 611 extern ULONGEST get_frame_memory_unsigned (struct frame_info *this_frame,
 612                                            CORE_ADDR memaddr, int len);
 613
 614 /* Same as above, but return non-zero when the entire memory read
 615    succeeds, zero otherwize.  */
 616 extern int safe_frame_unwind_memory (struct frame_info *this_frame,
 617                                      CORE_ADDR addr, gdb_byte *buf, int len);
 618
 619 /* Return this frame's architecture.  */
 620 extern struct gdbarch *get_frame_arch (struct frame_info *this_frame);
 621
 622 /* Return the previous frame's architecture.  */
 623 extern struct gdbarch *frame_unwind_arch (struct frame_info *frame);
 624
 625 /* Return the previous frame's architecture, skipping inline functions.  */
 626 extern struct gdbarch *frame_unwind_caller_arch (struct frame_info *frame);
 627
 628
 629 /* Values for the source flag to be used in print_frame_info_base().  */
 630 enum print_what
 631   {
 632     /* Print only the source line, like in stepi.  */
 633     SRC_LINE = -1,
 634     /* Print only the location, i.e. level, address (sometimes)
 635        function, args, file, line, line num.  */
 636     LOCATION,
 637     /* Print both of the above.  */
 638     SRC_AND_LOC,
 639     /* Print location only, but always include the address.  */
 640     LOC_AND_ADDRESS
 641   };
 642
 643 /* Allocate zero initialized memory from the frame cache obstack.
 644    Appendices to the frame info (such as the unwind cache) should
 645    allocate memory using this method.  */
 646
 647 extern void *frame_obstack_zalloc (unsigned long size);
 648 #define FRAME_OBSTACK_ZALLOC(TYPE) \
 649   ((TYPE *) frame_obstack_zalloc (sizeof (TYPE)))
 650 #define FRAME_OBSTACK_CALLOC(NUMBER,TYPE) \
 651   ((TYPE *) frame_obstack_zalloc ((NUMBER) * sizeof (TYPE)))
 652
 653 /* Create a regcache, and copy the frame's registers into it.  */
 654 struct regcache *frame_save_as_regcache (struct frame_info *this_frame);
 655
 656 extern struct block *get_frame_block (struct frame_info *,
 657                                       CORE_ADDR *addr_in_block);
 658
 659 /* Return the `struct block' that belongs to the selected thread's
 660    selected frame.  If the inferior has no state, return NULL.
 661
 662    NOTE: cagney/2002-11-29:
 663
 664    No state?  Does the inferior have any execution state (a core file
 665    does, an executable does not).  At present the code tests
 666    `target_has_stack' but I'm left wondering if it should test
 667    `target_has_registers' or, even, a merged target_has_state.
 668
 669    Should it look at the most recently specified SAL?  If the target
 670    has no state, should this function try to extract a block from the
 671    most recently selected SAL?  That way `list foo' would give it some
 672    sort of reference point.  Then again, perhaps that would confuse
 673    things.
 674
 675    Calls to this function can be broken down into two categories: Code
 676    that uses the selected block as an additional, but optional, data
 677    point; Code that uses the selected block as a prop, when it should
 678    have the relevant frame/block/pc explicitly passed in.
 679
 680    The latter can be eliminated by correctly parameterizing the code,
 681    the former though is more interesting.  Per the "address" command,
 682    it occurs in the CLI code and makes it possible for commands to
 683    work, even when the inferior has no state.  */
 684
 685 extern struct block *get_selected_block (CORE_ADDR *addr_in_block);
 686
 687 extern struct symbol *get_frame_function (struct frame_info *);
 688
 689 extern CORE_ADDR get_pc_function_start (CORE_ADDR);
 690
 691 extern struct frame_info *find_relative_frame (struct frame_info *, int *);
 692
 693 extern void print_stack_frame (struct frame_info *, int print_level,
 694                                enum print_what print_what,
 695                                int set_current_sal);
 696
 697 extern void print_frame_info (struct frame_info *, int print_level,
 698                               enum print_what print_what, int args,
 699                               int set_current_sal);
 700
 701 extern struct frame_info *block_innermost_frame (const struct block *);
 702
 703 extern int deprecated_frame_register_read (struct frame_info *frame, int regnum,
 704                                 gdb_byte *buf);
 705
 706 /* From stack.c.  */
 707
 708 extern const char print_entry_values_no[];
 709 extern const char print_entry_values_only[];
 710 extern const char print_entry_values_preferred[];
 711 extern const char print_entry_values_if_needed[];
 712 extern const char print_entry_values_both[];
 713 extern const char print_entry_values_compact[];
 714 extern const char print_entry_values_default[];
 715 extern const char *print_entry_values;
 716
 717 /* Inferior function parameter value read in from a frame.  */
 718
 719 struct frame_arg
 720 {
 721   /* Symbol for this parameter used for example for its name.  */
 722   struct symbol *sym;
 723
 724   /* Value of the parameter.  It is NULL if ERROR is not NULL; if both VAL and
 725      ERROR are NULL this parameter's value should not be printed.  */
 726   struct value *val;
 727
 728   /* String containing the error message, it is more usually NULL indicating no
 729      error occured reading this parameter.  */
 730   char *error;
 731
 732   /* One of the print_entry_values_* entries as appropriate specifically for
 733      this frame_arg.  It will be different from print_entry_values.  With
 734      print_entry_values_no this frame_arg should be printed as a normal
 735      parameter.  print_entry_values_only says it should be printed as entry
 736      value parameter.  print_entry_values_compact says it should be printed as
 737      both as a normal parameter and entry values parameter having the same
 738      value - print_entry_values_compact is not permitted fi ui_out_is_mi_like_p
 739      (in such case print_entry_values_no and print_entry_values_only is used
 740      for each parameter kind specifically.  */
 741   const char *entry_kind;
 742 };
 743
 744 extern void read_frame_arg (struct symbol *sym, struct frame_info *frame,
 745                             struct frame_arg *argp,
 746                             struct frame_arg *entryargp);
 747 extern void read_frame_local (struct symbol *sym, struct frame_info *frame,
 748                               struct frame_arg *argp);
 749
 750 extern void args_info (char *, int);
 751
 752 extern void locals_info (char *, int);
 753
 754 extern void (*deprecated_selected_frame_level_changed_hook) (int);
 755
 756 extern void return_command (char *, int);
 757
 758 /* Set FRAME's unwinder temporarily, so that we can call a sniffer.
 759    Return a cleanup which should be called if unwinding fails, and
 760    discarded if it succeeds.  */
 761
 762 struct cleanup *frame_prepare_for_sniffer (struct frame_info *frame,
 763                                            const struct frame_unwind *unwind);
 764
 765 /* Notes (cagney/2002-11-27, drow/2003-09-06):
 766
 767    You might think that calls to this function can simply be replaced by a
 768    call to get_selected_frame().
 769
 770    Unfortunately, it isn't that easy.
 771
 772    The relevant code needs to be audited to determine if it is
 773    possible (or practical) to instead pass the applicable frame in as a
 774    parameter.  For instance, DEPRECATED_DO_REGISTERS_INFO() relied on
 775    the deprecated_selected_frame global, while its replacement,
 776    PRINT_REGISTERS_INFO(), is parameterized with the selected frame.
 777    The only real exceptions occur at the edge (in the CLI code) where
 778    user commands need to pick up the selected frame before proceeding.
 779
 780    There are also some functions called with a NULL frame meaning either "the
 781    program is not running" or "use the selected frame".
 782
 783    This is important.  GDB is trying to stamp out the hack:
 784
 785    saved_frame = deprecated_safe_get_selected_frame ();
 786    select_frame (...);
 787    hack_using_global_selected_frame ();
 788    select_frame (saved_frame);
 789
 790    Take care!
 791
 792    This function calls get_selected_frame if the inferior should have a
 793    frame, or returns NULL otherwise.  */
 794
 795 extern struct frame_info *deprecated_safe_get_selected_frame (void);
 796
 797 /* Create a frame using the specified BASE and PC.  */
 798
 799 extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc);
 800
 801 /* Return true if the frame unwinder for frame FI is UNWINDER; false
 802    otherwise.  */
 803
 804 extern int frame_unwinder_is (struct frame_info *fi,
 805                               const struct frame_unwind *unwinder);
 806
 807 #endif /* !defined (FRAME_H)  */