gdb/value.h

   1 /* Definitions for values of C expressions, for GDB.
   2
   3    Copyright (C) 1986-2013 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #if !defined (VALUE_H)
  21 #define VALUE_H 1
  22
  23 #include "doublest.h"
  24 #include "frame.h"              /* For struct frame_id.  */
  25
  26 struct block;
  27 struct expression;
  28 struct regcache;
  29 struct symbol;
  30 struct type;
  31 struct ui_file;
  32 struct language_defn;
  33 struct value_print_options;
  34
  35 /* The structure which defines the type of a value.  It should never
  36    be possible for a program lval value to survive over a call to the
  37    inferior (i.e. to be put into the history list or an internal
  38    variable).  */
  39
  40 struct value;
  41
  42 /* Values are stored in a chain, so that they can be deleted easily
  43    over calls to the inferior.  Values assigned to internal variables,
  44    put into the value history or exposed to Python are taken off this
  45    list.  */
  46
  47 struct value *value_next (struct value *);
  48
  49 /* Type of the value.  */
  50
  51 extern struct type *value_type (const struct value *);
  52
  53 /* This is being used to change the type of an existing value, that
  54    code should instead be creating a new value with the changed type
  55    (but possibly shared content).  */
  56
  57 extern void deprecated_set_value_type (struct value *value,
  58                                        struct type *type);
  59
  60 /* Only used for bitfields; number of bits contained in them.  */
  61
  62 extern int value_bitsize (const struct value *);
  63 extern void set_value_bitsize (struct value *, int bit);
  64
  65 /* Only used for bitfields; position of start of field.  For
  66    gdbarch_bits_big_endian=0 targets, it is the position of the LSB.  For
  67    gdbarch_bits_big_endian=1 targets, it is the position of the MSB.  */
  68
  69 extern int value_bitpos (const struct value *);
  70 extern void set_value_bitpos (struct value *, int bit);
  71
  72 /* Only used for bitfields; the containing value.  This allows a
  73    single read from the target when displaying multiple
  74    bitfields.  */
  75
  76 struct value *value_parent (struct value *);
  77 extern void set_value_parent (struct value *value, struct value *parent);
  78
  79 /* Describes offset of a value within lval of a structure in bytes.
  80    If lval == lval_memory, this is an offset to the address.  If lval
  81    == lval_register, this is a further offset from location.address
  82    within the registers structure.  Note also the member
  83    embedded_offset below.  */
  84
  85 extern int value_offset (const struct value *);
  86 extern void set_value_offset (struct value *, int offset);
  87
  88 /* The comment from "struct value" reads: ``Is it modifiable?  Only
  89    relevant if lval != not_lval.''.  Shouldn't the value instead be
  90    not_lval and be done with it?  */
  91
  92 extern int deprecated_value_modifiable (struct value *value);
  93 extern void deprecated_set_value_modifiable (struct value *value,
  94                                              int modifiable);
  95
  96 /* If a value represents a C++ object, then the `type' field gives the
  97    object's compile-time type.  If the object actually belongs to some
  98    class derived from `type', perhaps with other base classes and
  99    additional members, then `type' is just a subobject of the real
 100    thing, and the full object is probably larger than `type' would
 101    suggest.
 102
 103    If `type' is a dynamic class (i.e. one with a vtable), then GDB can
 104    actually determine the object's run-time type by looking at the
 105    run-time type information in the vtable.  When this information is
 106    available, we may elect to read in the entire object, for several
 107    reasons:
 108
 109    - When printing the value, the user would probably rather see the
 110      full object, not just the limited portion apparent from the
 111      compile-time type.
 112
 113    - If `type' has virtual base classes, then even printing `type'
 114      alone may require reaching outside the `type' portion of the
 115      object to wherever the virtual base class has been stored.
 116
 117    When we store the entire object, `enclosing_type' is the run-time
 118    type -- the complete object -- and `embedded_offset' is the offset
 119    of `type' within that larger type, in bytes.  The value_contents()
 120    macro takes `embedded_offset' into account, so most GDB code
 121    continues to see the `type' portion of the value, just as the
 122    inferior would.
 123
 124    If `type' is a pointer to an object, then `enclosing_type' is a
 125    pointer to the object's run-time type, and `pointed_to_offset' is
 126    the offset in bytes from the full object to the pointed-to object
 127    -- that is, the value `embedded_offset' would have if we followed
 128    the pointer and fetched the complete object.  (I don't really see
 129    the point.  Why not just determine the run-time type when you
 130    indirect, and avoid the special case?  The contents don't matter
 131    until you indirect anyway.)
 132
 133    If we're not doing anything fancy, `enclosing_type' is equal to
 134    `type', and `embedded_offset' is zero, so everything works
 135    normally.  */
 136
 137 extern struct type *value_enclosing_type (struct value *);
 138 extern void set_value_enclosing_type (struct value *val,
 139                                       struct type *new_type);
 140
 141 /* Returns value_type or value_enclosing_type depending on
 142    value_print_options.objectprint.
 143
 144    If RESOLVE_SIMPLE_TYPES is 0 the enclosing type will be resolved
 145    only for pointers and references, else it will be returned
 146    for all the types (e.g. structures).  This option is useful
 147    to prevent retrieving enclosing type for the base classes fields.
 148
 149    REAL_TYPE_FOUND is used to inform whether the real type was found
 150    (or just static type was used).  The NULL may be passed if it is not
 151    necessary. */
 152
 153 extern struct type *value_actual_type (struct value *value,
 154                                        int resolve_simple_types,
 155                                        int *real_type_found);
 156
 157 extern int value_pointed_to_offset (struct value *value);
 158 extern void set_value_pointed_to_offset (struct value *value, int val);
 159 extern int value_embedded_offset (struct value *value);
 160 extern void set_value_embedded_offset (struct value *value, int val);
 161
 162 /* For lval_computed values, this structure holds functions used to
 163    retrieve and set the value (or portions of the value).
 164
 165    For each function, 'V' is the 'this' pointer: an lval_funcs
 166    function F may always assume that the V it receives is an
 167    lval_computed value, and has F in the appropriate slot of its
 168    lval_funcs structure.  */
 169
 170 struct lval_funcs
 171 {
 172   /* Fill in VALUE's contents.  This is used to "un-lazy" values.  If
 173      a problem arises in obtaining VALUE's bits, this function should
 174      call 'error'.  If it is NULL value_fetch_lazy on "un-lazy"
 175      non-optimized-out value is an internal error.  */
 176   void (*read) (struct value *v);
 177
 178   /* Handle an assignment TOVAL = FROMVAL by writing the value of
 179      FROMVAL to TOVAL's location.  The contents of TOVAL have not yet
 180      been updated.  If a problem arises in doing so, this function
 181      should call 'error'.  If it is NULL such TOVAL assignment is an error as
 182      TOVAL is not considered as an lvalue.  */
 183   void (*write) (struct value *toval, struct value *fromval);
 184
 185   /* Check the validity of some bits in VALUE.  This should return 1
 186      if all the bits starting at OFFSET and extending for LENGTH bits
 187      are valid, or 0 if any bit is invalid.  */
 188   int (*check_validity) (const struct value *value, int offset, int length);
 189
 190   /* Return 1 if any bit in VALUE is valid, 0 if they are all invalid.  */
 191   int (*check_any_valid) (const struct value *value);
 192
 193   /* If non-NULL, this is used to implement pointer indirection for
 194      this value.  This method may return NULL, in which case value_ind
 195      will fall back to ordinary indirection.  */
 196   struct value *(*indirect) (struct value *value);
 197
 198   /* If non-NULL, this is used to implement reference resolving for
 199      this value.  This method may return NULL, in which case coerce_ref
 200      will fall back to ordinary references resolving.  */
 201   struct value *(*coerce_ref) (const struct value *value);
 202
 203   /* If non-NULL, this is used to determine whether the indicated bits
 204      of VALUE are a synthetic pointer.  */
 205   int (*check_synthetic_pointer) (const struct value *value,
 206                                   int offset, int length);
 207
 208   /* Return a duplicate of VALUE's closure, for use in a new value.
 209      This may simply return the same closure, if VALUE's is
 210      reference-counted or statically allocated.
 211
 212      This may be NULL, in which case VALUE's closure is re-used in the
 213      new value.  */
 214   void *(*copy_closure) (const struct value *v);
 215
 216   /* Drop VALUE's reference to its closure.  Maybe this frees the
 217      closure; maybe this decrements a reference count; maybe the
 218      closure is statically allocated and this does nothing.
 219
 220      This may be NULL, in which case no action is taken to free
 221      VALUE's closure.  */
 222   void (*free_closure) (struct value *v);
 223 };
 224
 225 /* Create a computed lvalue, with type TYPE, function pointers FUNCS,
 226    and closure CLOSURE.  */
 227
 228 extern struct value *allocate_computed_value (struct type *type,
 229                                               const struct lval_funcs *funcs,
 230                                               void *closure);
 231
 232 /* Helper function to check the validity of some bits of a value.
 233
 234    If TYPE represents some aggregate type (e.g., a structure), return 1.
 235
 236    Otherwise, any of the bytes starting at OFFSET and extending for
 237    TYPE_LENGTH(TYPE) bytes are invalid, print a message to STREAM and
 238    return 0.  The checking is done using FUNCS.
 239
 240    Otherwise, return 1.  */
 241
 242 extern int valprint_check_validity (struct ui_file *stream, struct type *type,
 243                                     int embedded_offset,
 244                                     const struct value *val);
 245
 246 extern struct value *allocate_optimized_out_value (struct type *type);
 247
 248 /* If VALUE is lval_computed, return its lval_funcs structure.  */
 249
 250 extern const struct lval_funcs *value_computed_funcs (const struct value *);
 251
 252 /* If VALUE is lval_computed, return its closure.  The meaning of the
 253    returned value depends on the functions VALUE uses.  */
 254
 255 extern void *value_computed_closure (const struct value *value);
 256
 257 /* If zero, contents of this value are in the contents field.  If
 258    nonzero, contents are in inferior.  If the lval field is lval_memory,
 259    the contents are in inferior memory at location.address plus offset.
 260    The lval field may also be lval_register.
 261
 262    WARNING: This field is used by the code which handles watchpoints
 263    (see breakpoint.c) to decide whether a particular value can be
 264    watched by hardware watchpoints.  If the lazy flag is set for some
 265    member of a value chain, it is assumed that this member of the
 266    chain doesn't need to be watched as part of watching the value
 267    itself.  This is how GDB avoids watching the entire struct or array
 268    when the user wants to watch a single struct member or array
 269    element.  If you ever change the way lazy flag is set and reset, be
 270    sure to consider this use as well!  */
 271
 272 extern int value_lazy (struct value *);
 273 extern void set_value_lazy (struct value *value, int val);
 274
 275 extern int value_stack (struct value *);
 276 extern void set_value_stack (struct value *value, int val);
 277
 278 /* value_contents() and value_contents_raw() both return the address
 279    of the gdb buffer used to hold a copy of the contents of the lval.
 280    value_contents() is used when the contents of the buffer are needed
 281    -- it uses value_fetch_lazy() to load the buffer from the process
 282    being debugged if it hasn't already been loaded
 283    (value_contents_writeable() is used when a writeable but fetched
 284    buffer is required)..  value_contents_raw() is used when data is
 285    being stored into the buffer, or when it is certain that the
 286    contents of the buffer are valid.
 287
 288    Note: The contents pointer is adjusted by the offset required to
 289    get to the real subobject, if the value happens to represent
 290    something embedded in a larger run-time object.  */
 291
 292 extern gdb_byte *value_contents_raw (struct value *);
 293
 294 /* Actual contents of the value.  For use of this value; setting it
 295    uses the stuff above.  Not valid if lazy is nonzero.  Target
 296    byte-order.  We force it to be aligned properly for any possible
 297    value.  Note that a value therefore extends beyond what is
 298    declared here.  */
 299
 300 extern const gdb_byte *value_contents (struct value *);
 301 extern gdb_byte *value_contents_writeable (struct value *);
 302
 303 /* The ALL variants of the above two macros do not adjust the returned
 304    pointer by the embedded_offset value.  */
 305
 306 extern gdb_byte *value_contents_all_raw (struct value *);
 307 extern const gdb_byte *value_contents_all (struct value *);
 308
 309 /* Like value_contents_all, but does not require that the returned
 310    bits be valid.  This should only be used in situations where you
 311    plan to check the validity manually.  */
 312 extern const gdb_byte *value_contents_for_printing (struct value *value);
 313
 314 /* Like value_contents_for_printing, but accepts a constant value
 315    pointer.  Unlike value_contents_for_printing however, the pointed
 316    value must _not_ be lazy.  */
 317 extern const gdb_byte *
 318   value_contents_for_printing_const (const struct value *value);
 319
 320 extern int value_fetch_lazy (struct value *val);
 321 extern int value_contents_equal (struct value *val1, struct value *val2);
 322
 323 /* If nonzero, this is the value of a variable which does not actually
 324    exist in the program.  */
 325 extern int value_optimized_out (struct value *value);
 326 extern void set_value_optimized_out (struct value *value, int val);
 327
 328 /* Like value_optimized_out, but return false if any bit in the object
 329    is valid.  */
 330 extern int value_entirely_optimized_out (const struct value *value);
 331
 332 /* Set or return field indicating whether a variable is initialized or
 333    not, based on debugging information supplied by the compiler.
 334    1 = initialized; 0 = uninitialized.  */
 335 extern int value_initialized (struct value *);
 336 extern void set_value_initialized (struct value *, int);
 337
 338 /* Set COMPONENT's location as appropriate for a component of WHOLE
 339    --- regardless of what kind of lvalue WHOLE is.  */
 340 extern void set_value_component_location (struct value *component,
 341                                           const struct value *whole);
 342
 343 /* While the following fields are per- VALUE .CONTENT .PIECE (i.e., a
 344    single value might have multiple LVALs), this hacked interface is
 345    limited to just the first PIECE.  Expect further change.  */
 346 /* Type of value; either not an lval, or one of the various different
 347    possible kinds of lval.  */
 348 extern enum lval_type *deprecated_value_lval_hack (struct value *);
 349 #define VALUE_LVAL(val) (*deprecated_value_lval_hack (val))
 350
 351 /* Like VALUE_LVAL, except the parameter can be const.  */
 352 extern enum lval_type value_lval_const (const struct value *value);
 353
 354 /* If lval == lval_memory, return the address in the inferior.  If
 355    lval == lval_register, return the byte offset into the registers
 356    structure.  Otherwise, return 0.  The returned address
 357    includes the offset, if any.  */
 358 extern CORE_ADDR value_address (const struct value *);
 359
 360 /* Like value_address, except the result does not include value's
 361    offset.  */
 362 extern CORE_ADDR value_raw_address (struct value *);
 363
 364 /* Set the address of a value.  */
 365 extern void set_value_address (struct value *, CORE_ADDR);
 366
 367 /* Pointer to internal variable.  */
 368 extern struct internalvar **deprecated_value_internalvar_hack (struct value *);
 369 #define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val))
 370
 371 /* Frame register value is relative to.  This will be described in the
 372    lval enum above as "lval_register".  */
 373 extern struct frame_id *deprecated_value_frame_id_hack (struct value *);
 374 #define VALUE_FRAME_ID(val) (*deprecated_value_frame_id_hack (val))
 375
 376 /* Register number if the value is from a register.  */
 377 extern short *deprecated_value_regnum_hack (struct value *);
 378 #define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val))
 379
 380 /* Return value after lval_funcs->coerce_ref (after check_typedef).  Return
 381    NULL if lval_funcs->coerce_ref is not applicable for whatever reason.  */
 382
 383 extern struct value *coerce_ref_if_computed (const struct value *arg);
 384
 385 /* Setup a new value type and enclosing value type for dereferenced value VALUE.
 386    ENC_TYPE is the new enclosing type that should be set.  ORIGINAL_TYPE and
 387    ORIGINAL_VAL are the type and value of the original reference or pointer.
 388
 389    Note, that VALUE is modified by this function.
 390
 391    It is a common implementation for coerce_ref and value_ind.  */
 392
 393 extern struct value * readjust_indirect_value_type (struct value *value,
 394                                                     struct type *enc_type,
 395                                                     struct type *original_type,
 396                                                     struct value *original_val);
 397
 398 /* Convert a REF to the object referenced.  */
 399
 400 extern struct value *coerce_ref (struct value *value);
 401
 402 /* If ARG is an array, convert it to a pointer.
 403    If ARG is a function, convert it to a function pointer.
 404
 405    References are dereferenced.  */
 406
 407 extern struct value *coerce_array (struct value *value);
 408
 409 /* Given a value, determine whether the bits starting at OFFSET and
 410    extending for LENGTH bits are valid.  This returns nonzero if all
 411    bits in the given range are valid, zero if any bit is invalid.  */
 412
 413 extern int value_bits_valid (const struct value *value,
 414                              int offset, int length);
 415
 416 /* Given a value, determine whether the bits starting at OFFSET and
 417    extending for LENGTH bits are a synthetic pointer.  */
 418
 419 extern int value_bits_synthetic_pointer (const struct value *value,
 420                                          int offset, int length);
 421
 422 /* Given a value, determine whether the contents bytes starting at
 423    OFFSET and extending for LENGTH bytes are available.  This returns
 424    nonzero if all bytes in the given range are available, zero if any
 425    byte is unavailable.  */
 426
 427 extern int value_bytes_available (const struct value *value,
 428                                   int offset, int length);
 429
 430 /* Like value_bytes_available, but return false if any byte in the
 431    whole object is unavailable.  */
 432 extern int value_entirely_available (struct value *value);
 433
 434 /* Mark VALUE's content bytes starting at OFFSET and extending for
 435    LENGTH bytes as unavailable.  */
 436
 437 extern void mark_value_bytes_unavailable (struct value *value,
 438                                           int offset, int length);
 439
 440 /* Compare LENGTH bytes of VAL1's contents starting at OFFSET1 with
 441    LENGTH bytes of VAL2's contents starting at OFFSET2.
 442
 443    Note that "contents" refers to the whole value's contents
 444    (value_contents_all), without any embedded offset adjustment.  For
 445    example, to compare a complete object value with itself, including
 446    its enclosing type chunk, you'd do:
 447
 448      int len = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
 449      value_available_contents (val, 0, val, 0, len);
 450
 451    Returns true iff the set of available contents match.  Unavailable
 452    contents compare equal with unavailable contents, and different
 453    with any available byte.  For example, if 'x's represent an
 454    unavailable byte, and 'V' and 'Z' represent different available
 455    bytes, in a value with length 16:
 456
 457    offset:   0   4   8   12  16
 458    contents: xxxxVVVVxxxxVVZZ
 459
 460    then:
 461
 462    value_available_contents_eq(val, 0, val, 8, 6) => 1
 463    value_available_contents_eq(val, 0, val, 4, 4) => 1
 464    value_available_contents_eq(val, 0, val, 8, 8) => 0
 465    value_available_contents_eq(val, 4, val, 12, 2) => 1
 466    value_available_contents_eq(val, 4, val, 12, 4) => 0
 467    value_available_contents_eq(val, 3, val, 4, 4) => 0
 468 */
 469
 470 extern int value_available_contents_eq (const struct value *val1, int offset1,
 471                                         const struct value *val2, int offset2,
 472                                         int length);
 473
 474 /* Read LENGTH bytes of memory starting at MEMADDR into BUFFER, which
 475    is (or will be copied to) VAL's contents buffer offset by
 476    EMBEDDED_OFFSET (that is, to &VAL->contents[EMBEDDED_OFFSET]).
 477    Marks value contents ranges as unavailable if the corresponding
 478    memory is likewise unavailable.  STACK indicates whether the memory
 479    is known to be stack memory.  */
 480
 481 extern void read_value_memory (struct value *val, int embedded_offset,
 482                                int stack, CORE_ADDR memaddr,
 483                                gdb_byte *buffer, size_t length);
 484
 485 \f
 486
 487 #include "symtab.h"
 488 #include "gdbtypes.h"
 489 #include "expression.h"
 490
 491 struct frame_info;
 492 struct fn_field;
 493
 494 extern int print_address_demangle (const struct value_print_options *,
 495                                    struct gdbarch *, CORE_ADDR,
 496                                    struct ui_file *, int);
 497
 498 extern LONGEST value_as_long (struct value *val);
 499 extern DOUBLEST value_as_double (struct value *val);
 500 extern CORE_ADDR value_as_address (struct value *val);
 501
 502 extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr);
 503 extern DOUBLEST unpack_double (struct type *type, const gdb_byte *valaddr,
 504                                int *invp);
 505 extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr);
 506
 507 extern int unpack_value_bits_as_long (struct type *field_type,
 508                                       const gdb_byte *valaddr,
 509                                       int embedded_offset, int bitpos,
 510                                       int bitsize,
 511                                       const struct value *original_value,
 512                                       LONGEST *result);
 513
 514 extern LONGEST unpack_field_as_long (struct type *type,
 515                                      const gdb_byte *valaddr,
 516                                      int fieldno);
 517 extern int unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr,
 518                                 int embedded_offset, int fieldno,
 519                                 const struct value *val, LONGEST *result);
 520
 521 extern struct value *value_field_bitfield (struct type *type, int fieldno,
 522                                            const gdb_byte *valaddr,
 523                                            int embedded_offset,
 524                                            const struct value *val);
 525
 526 extern void pack_long (gdb_byte *buf, struct type *type, LONGEST num);
 527
 528 extern struct value *value_from_longest (struct type *type, LONGEST num);
 529 extern struct value *value_from_ulongest (struct type *type, ULONGEST num);
 530 extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr);
 531 extern struct value *value_from_double (struct type *type, DOUBLEST num);
 532 extern struct value *value_from_decfloat (struct type *type,
 533                                           const gdb_byte *decbytes);
 534 extern struct value *value_from_history_ref (char *, char **);
 535
 536 extern struct value *value_at (struct type *type, CORE_ADDR addr);
 537 extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr);
 538
 539 extern struct value *value_from_contents_and_address (struct type *,
 540                                                       const gdb_byte *,
 541                                                       CORE_ADDR);
 542 extern struct value *value_from_contents (struct type *, const gdb_byte *);
 543
 544 extern struct value *default_value_from_register (struct type *type,
 545                                                   int regnum,
 546                                                   struct frame_info *frame);
 547
 548 extern void read_frame_register_value (struct value *value,
 549                                        struct frame_info *frame);
 550
 551 extern struct value *value_from_register (struct type *type, int regnum,
 552                                           struct frame_info *frame);
 553
 554 extern CORE_ADDR address_from_register (struct type *type, int regnum,
 555                                         struct frame_info *frame);
 556
 557 extern struct value *value_of_variable (struct symbol *var,
 558                                         const struct block *b);
 559
 560 extern struct value *address_of_variable (struct symbol *var,
 561                                           const struct block *b);
 562
 563 extern struct value *value_of_register (int regnum, struct frame_info *frame);
 564
 565 struct value *value_of_register_lazy (struct frame_info *frame, int regnum);
 566
 567 extern int symbol_read_needs_frame (struct symbol *);
 568
 569 extern struct value *read_var_value (struct symbol *var,
 570                                      struct frame_info *frame);
 571
 572 extern struct value *default_read_var_value (struct symbol *var,
 573                                              struct frame_info *frame);
 574
 575 extern struct value *allocate_value (struct type *type);
 576 extern struct value *allocate_value_lazy (struct type *type);
 577 extern void allocate_value_contents (struct value *value);
 578 extern void value_contents_copy (struct value *dst, int dst_offset,
 579                                  struct value *src, int src_offset,
 580                                  int length);
 581 extern void value_contents_copy_raw (struct value *dst, int dst_offset,
 582                                      struct value *src, int src_offset,
 583                                      int length);
 584
 585 extern struct value *allocate_repeat_value (struct type *type, int count);
 586
 587 extern struct value *value_mark (void);
 588
 589 extern void value_free_to_mark (struct value *mark);
 590
 591 extern struct value *value_cstring (char *ptr, ssize_t len,
 592                                     struct type *char_type);
 593 extern struct value *value_string (char *ptr, ssize_t len,
 594                                    struct type *char_type);
 595
 596 extern struct value *value_array (int lowbound, int highbound,
 597                                   struct value **elemvec);
 598
 599 extern struct value *value_concat (struct value *arg1, struct value *arg2);
 600
 601 extern struct value *value_binop (struct value *arg1, struct value *arg2,
 602                                   enum exp_opcode op);
 603
 604 extern struct value *value_ptradd (struct value *arg1, LONGEST arg2);
 605
 606 extern LONGEST value_ptrdiff (struct value *arg1, struct value *arg2);
 607
 608 extern int value_must_coerce_to_target (struct value *arg1);
 609
 610 extern struct value *value_coerce_to_target (struct value *arg1);
 611
 612 extern struct value *value_coerce_array (struct value *arg1);
 613
 614 extern struct value *value_coerce_function (struct value *arg1);
 615
 616 extern struct value *value_ind (struct value *arg1);
 617
 618 extern struct value *value_addr (struct value *arg1);
 619
 620 extern struct value *value_ref (struct value *arg1);
 621
 622 extern struct value *value_assign (struct value *toval,
 623                                    struct value *fromval);
 624
 625 extern struct value *value_pos (struct value *arg1);
 626
 627 extern struct value *value_neg (struct value *arg1);
 628
 629 extern struct value *value_complement (struct value *arg1);
 630
 631 extern struct value *value_struct_elt (struct value **argp,
 632                                        struct value **args,
 633                                        const char *name, int *static_memfuncp,
 634                                        const char *err);
 635
 636 extern struct value *value_aggregate_elt (struct type *curtype,
 637                                           char *name,
 638                                           struct type *expect_type,
 639                                           int want_address,
 640                                           enum noside noside);
 641
 642 extern struct value *value_static_field (struct type *type, int fieldno);
 643
 644 enum oload_search_type { NON_METHOD, METHOD, BOTH };
 645
 646 extern int find_overload_match (struct value **args, int nargs,
 647                                 const char *name,
 648                                 enum oload_search_type method, int lax,
 649                                 struct value **objp, struct symbol *fsym,
 650                                 struct value **valp, struct symbol **symp,
 651                                 int *staticp, const int no_adl);
 652
 653 extern struct value *value_field (struct value *arg1, int fieldno);
 654
 655 extern struct value *value_primitive_field (struct value *arg1, int offset,
 656                                             int fieldno,
 657                                             struct type *arg_type);
 658
 659
 660 extern struct type *value_rtti_indirect_type (struct value *, int *, int *,
 661                                               int *);
 662
 663 extern struct value *value_full_object (struct value *, struct type *, int,
 664                                         int, int);
 665
 666 extern struct value *value_cast_pointers (struct type *, struct value *, int);
 667
 668 extern struct value *value_cast (struct type *type, struct value *arg2);
 669
 670 extern struct value *value_reinterpret_cast (struct type *type,
 671                                              struct value *arg);
 672
 673 extern struct value *value_dynamic_cast (struct type *type, struct value *arg);
 674
 675 extern struct value *value_zero (struct type *type, enum lval_type lv);
 676
 677 extern struct value *value_one (struct type *type);
 678
 679 extern struct value *value_repeat (struct value *arg1, int count);
 680
 681 extern struct value *value_subscript (struct value *array, LONGEST index);
 682
 683 extern struct value *value_bitstring_subscript (struct type *type,
 684                                                 struct value *bitstring,
 685                                                 LONGEST index);
 686
 687 extern struct value *register_value_being_returned (struct type *valtype,
 688                                                     struct regcache *retbuf);
 689
 690 extern int value_in (struct value *element, struct value *set);
 691
 692 extern int value_bit_index (struct type *type, const gdb_byte *addr,
 693                             int index);
 694
 695 extern int using_struct_return (struct gdbarch *gdbarch,
 696                                 struct value *function,
 697                                 struct type *value_type);
 698
 699 extern struct value *evaluate_expression (struct expression *exp);
 700
 701 extern struct value *evaluate_type (struct expression *exp);
 702
 703 extern struct value *evaluate_subexp (struct type *expect_type,
 704                                       struct expression *exp,
 705                                       int *pos, enum noside noside);
 706
 707 extern struct value *evaluate_subexpression_type (struct expression *exp,
 708                                                   int subexp);
 709
 710 extern void fetch_subexp_value (struct expression *exp, int *pc,
 711                                 struct value **valp, struct value **resultp,
 712                                 struct value **val_chain);
 713
 714 extern char *extract_field_op (struct expression *exp, int *subexp);
 715
 716 extern struct value *evaluate_subexp_with_coercion (struct expression *,
 717                                                     int *, enum noside);
 718
 719 extern struct value *parse_and_eval (char *exp);
 720
 721 extern struct value *parse_to_comma_and_eval (char **expp);
 722
 723 extern struct type *parse_and_eval_type (char *p, int length);
 724
 725 extern CORE_ADDR parse_and_eval_address (char *exp);
 726
 727 extern LONGEST parse_and_eval_long (char *exp);
 728
 729 extern void unop_promote (const struct language_defn *language,
 730                           struct gdbarch *gdbarch,
 731                           struct value **arg1);
 732
 733 extern void binop_promote (const struct language_defn *language,
 734                            struct gdbarch *gdbarch,
 735                            struct value **arg1, struct value **arg2);
 736
 737 extern struct value *access_value_history (int num);
 738
 739 extern struct value *value_of_internalvar (struct gdbarch *gdbarch,
 740                                            struct internalvar *var);
 741
 742 extern int get_internalvar_integer (struct internalvar *var, LONGEST *l);
 743
 744 extern void set_internalvar (struct internalvar *var, struct value *val);
 745
 746 extern void set_internalvar_integer (struct internalvar *var, LONGEST l);
 747
 748 extern void set_internalvar_string (struct internalvar *var,
 749                                     const char *string);
 750
 751 extern void clear_internalvar (struct internalvar *var);
 752
 753 extern void set_internalvar_component (struct internalvar *var,
 754                                        int offset,
 755                                        int bitpos, int bitsize,
 756                                        struct value *newvalue);
 757
 758 extern struct internalvar *lookup_only_internalvar (const char *name);
 759
 760 extern struct internalvar *create_internalvar (const char *name);
 761
 762 extern VEC (char_ptr) *complete_internalvar (const char *name);
 763
 764 /* An internalvar can be dynamically computed by supplying a vector of
 765    function pointers to perform various operations.  */
 766
 767 struct internalvar_funcs
 768 {
 769   /* Compute the value of the variable.  The DATA argument passed to
 770      the function is the same argument that was passed to
 771      `create_internalvar_type_lazy'.  */
 772
 773   struct value *(*make_value) (struct gdbarch *arch,
 774                                struct internalvar *var,
 775                                void *data);
 776
 777   /* Update the agent expression EXPR with bytecode to compute the
 778      value.  VALUE is the agent value we are updating.  The DATA
 779      argument passed to this function is the same argument that was
 780      passed to `create_internalvar_type_lazy'.  If this pointer is
 781      NULL, then the internalvar cannot be compiled to an agent
 782      expression.  */
 783
 784   void (*compile_to_ax) (struct internalvar *var,
 785                          struct agent_expr *expr,
 786                          struct axs_value *value,
 787                          void *data);
 788
 789   /* If non-NULL, this is called to destroy DATA.  The DATA argument
 790      passed to this function is the same argument that was passed to
 791      `create_internalvar_type_lazy'.  */
 792
 793   void (*destroy) (void *data);
 794 };
 795
 796 extern struct internalvar *
 797 create_internalvar_type_lazy (const char *name,
 798                               const struct internalvar_funcs *funcs,
 799                               void *data);
 800
 801 /* Compile an internal variable to an agent expression.  VAR is the
 802    variable to compile; EXPR and VALUE are the agent expression we are
 803    updating.  This will return 0 if there is no known way to compile
 804    VAR, and 1 if VAR was successfully compiled.  It may also throw an
 805    exception on error.  */
 806
 807 extern int compile_internalvar_to_ax (struct internalvar *var,
 808                                       struct agent_expr *expr,
 809                                       struct axs_value *value);
 810
 811 extern struct internalvar *lookup_internalvar (const char *name);
 812
 813 extern int value_equal (struct value *arg1, struct value *arg2);
 814
 815 extern int value_equal_contents (struct value *arg1, struct value *arg2);
 816
 817 extern int value_less (struct value *arg1, struct value *arg2);
 818
 819 extern int value_logical_not (struct value *arg1);
 820
 821 /* C++ */
 822
 823 extern struct value *value_of_this (const struct language_defn *lang);
 824
 825 extern struct value *value_of_this_silent (const struct language_defn *lang);
 826
 827 extern struct value *value_x_binop (struct value *arg1, struct value *arg2,
 828                                     enum exp_opcode op,
 829                                     enum exp_opcode otherop,
 830                                     enum noside noside);
 831
 832 extern struct value *value_x_unop (struct value *arg1, enum exp_opcode op,
 833                                    enum noside noside);
 834
 835 extern struct value *value_fn_field (struct value **arg1p, struct fn_field *f,
 836                                      int j, struct type *type, int offset);
 837
 838 extern int binop_types_user_defined_p (enum exp_opcode op,
 839                                        struct type *type1,
 840                                        struct type *type2);
 841
 842 extern int binop_user_defined_p (enum exp_opcode op, struct value *arg1,
 843                                  struct value *arg2);
 844
 845 extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1);
 846
 847 extern int destructor_name_p (const char *name, struct type *type);
 848
 849 extern void value_incref (struct value *val);
 850
 851 extern void value_free (struct value *val);
 852
 853 extern void free_all_values (void);
 854
 855 extern void free_value_chain (struct value *v);
 856
 857 extern void release_value (struct value *val);
 858
 859 extern void release_value_or_incref (struct value *val);
 860
 861 extern int record_latest_value (struct value *val);
 862
 863 extern void modify_field (struct type *type, gdb_byte *addr,
 864                           LONGEST fieldval, int bitpos, int bitsize);
 865
 866 extern void type_print (struct type *type, const char *varstring,
 867                         struct ui_file *stream, int show);
 868
 869 extern char *type_to_string (struct type *type);
 870
 871 extern gdb_byte *baseclass_addr (struct type *type, int index,
 872                                  gdb_byte *valaddr,
 873                                  struct value **valuep, int *errp);
 874
 875 extern void print_longest (struct ui_file *stream, int format,
 876                            int use_local, LONGEST val);
 877
 878 extern void print_floating (const gdb_byte *valaddr, struct type *type,
 879                             struct ui_file *stream);
 880
 881 extern void print_decimal_floating (const gdb_byte *valaddr, struct type *type,
 882                                     struct ui_file *stream);
 883
 884 extern void value_print (struct value *val, struct ui_file *stream,
 885                          const struct value_print_options *options);
 886
 887 extern void value_print_array_elements (struct value *val,
 888                                         struct ui_file *stream, int format,
 889                                         enum val_prettyprint pretty);
 890
 891 extern struct value *value_release_to_mark (struct value *mark);
 892
 893 extern void val_print (struct type *type, const gdb_byte *valaddr,
 894                        int embedded_offset, CORE_ADDR address,
 895                        struct ui_file *stream, int recurse,
 896                        const struct value *val,
 897                        const struct value_print_options *options,
 898                        const struct language_defn *language);
 899
 900 extern void common_val_print (struct value *val,
 901                               struct ui_file *stream, int recurse,
 902                               const struct value_print_options *options,
 903                               const struct language_defn *language);
 904
 905 extern int val_print_string (struct type *elttype, const char *encoding,
 906                              CORE_ADDR addr, int len,
 907                              struct ui_file *stream,
 908                              const struct value_print_options *options);
 909
 910 extern void print_variable_and_value (const char *name,
 911                                       struct symbol *var,
 912                                       struct frame_info *frame,
 913                                       struct ui_file *stream,
 914                                       int indent);
 915
 916 extern void typedef_print (struct type *type, struct symbol *news,
 917                            struct ui_file *stream);
 918
 919 extern char *internalvar_name (struct internalvar *var);
 920
 921 extern void preserve_values (struct objfile *);
 922
 923 /* From values.c */
 924
 925 extern struct value *value_copy (struct value *);
 926
 927 extern struct value *value_non_lval (struct value *);
 928
 929 extern void preserve_one_value (struct value *, struct objfile *, htab_t);
 930
 931 /* From valops.c */
 932
 933 extern struct value *varying_to_slice (struct value *);
 934
 935 extern struct value *value_slice (struct value *, int, int);
 936
 937 extern struct value *value_literal_complex (struct value *, struct value *,
 938                                             struct type *);
 939
 940 extern struct value *find_function_in_inferior (const char *,
 941                                                 struct objfile **);
 942
 943 extern struct value *value_allocate_space_in_inferior (int);
 944
 945 extern struct value *value_subscripted_rvalue (struct value *array,
 946                                                LONGEST index, int lowerbound);
 947
 948 /* User function handler.  */
 949
 950 typedef struct value *(*internal_function_fn) (struct gdbarch *gdbarch,
 951                                                const struct language_defn *language,
 952                                                void *cookie,
 953                                                int argc,
 954                                                struct value **argv);
 955
 956 void add_internal_function (const char *name, const char *doc,
 957                             internal_function_fn handler,
 958                             void *cookie);
 959
 960 struct value *call_internal_function (struct gdbarch *gdbarch,
 961                                       const struct language_defn *language,
 962                                       struct value *function,
 963                                       int argc, struct value **argv);
 964
 965 char *value_internal_function_name (struct value *);
 966
 967 #endif /* !defined (VALUE_H) */