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
  94 /* If a value represents a C++ object, then the `type' field gives the
  95    object's compile-time type.  If the object actually belongs to some
  96    class derived from `type', perhaps with other base classes and
  97    additional members, then `type' is just a subobject of the real
  98    thing, and the full object is probably larger than `type' would
  99    suggest.
 100
 101    If `type' is a dynamic class (i.e. one with a vtable), then GDB can
 102    actually determine the object's run-time type by looking at the
 103    run-time type information in the vtable.  When this information is
 104    available, we may elect to read in the entire object, for several
 105    reasons:
 106
 107    - When printing the value, the user would probably rather see the
 108      full object, not just the limited portion apparent from the
 109      compile-time type.
 110
 111    - If `type' has virtual base classes, then even printing `type'
 112      alone may require reaching outside the `type' portion of the
 113      object to wherever the virtual base class has been stored.
 114
 115    When we store the entire object, `enclosing_type' is the run-time
 116    type -- the complete object -- and `embedded_offset' is the offset
 117    of `type' within that larger type, in bytes.  The value_contents()
 118    macro takes `embedded_offset' into account, so most GDB code
 119    continues to see the `type' portion of the value, just as the
 120    inferior would.
 121
 122    If `type' is a pointer to an object, then `enclosing_type' is a
 123    pointer to the object's run-time type, and `pointed_to_offset' is
 124    the offset in bytes from the full object to the pointed-to object
 125    -- that is, the value `embedded_offset' would have if we followed
 126    the pointer and fetched the complete object.  (I don't really see
 127    the point.  Why not just determine the run-time type when you
 128    indirect, and avoid the special case?  The contents don't matter
 129    until you indirect anyway.)
 130
 131    If we're not doing anything fancy, `enclosing_type' is equal to
 132    `type', and `embedded_offset' is zero, so everything works
 133    normally.  */
 134
 135 extern struct type *value_enclosing_type (struct value *);
 136 extern void set_value_enclosing_type (struct value *val,
 137                                       struct type *new_type);
 138
 139 /* Returns value_type or value_enclosing_type depending on
 140    value_print_options.objectprint.
 141
 142    If RESOLVE_SIMPLE_TYPES is 0 the enclosing type will be resolved
 143    only for pointers and references, else it will be returned
 144    for all the types (e.g. structures).  This option is useful
 145    to prevent retrieving enclosing type for the base classes fields.
 146
 147    REAL_TYPE_FOUND is used to inform whether the real type was found
 148    (or just static type was used).  The NULL may be passed if it is not
 149    necessary. */
 150
 151 extern struct type *value_actual_type (struct value *value,
 152                                        int resolve_simple_types,
 153                                        int *real_type_found);
 154
 155 extern int value_pointed_to_offset (struct value *value);
 156 extern void set_value_pointed_to_offset (struct value *value, int val);
 157 extern int value_embedded_offset (struct value *value);
 158 extern void set_value_embedded_offset (struct value *value, int val);
 159
 160 /* For lval_computed values, this structure holds functions used to
 161    retrieve and set the value (or portions of the value).
 162
 163    For each function, 'V' is the 'this' pointer: an lval_funcs
 164    function F may always assume that the V it receives is an
 165    lval_computed value, and has F in the appropriate slot of its
 166    lval_funcs structure.  */
 167
 168 struct lval_funcs
 169 {
 170   /* Fill in VALUE's contents.  This is used to "un-lazy" values.  If
 171      a problem arises in obtaining VALUE's bits, this function should
 172      call 'error'.  If it is NULL value_fetch_lazy on "un-lazy"
 173      non-optimized-out value is an internal error.  */
 174   void (*read) (struct value *v);
 175
 176   /* Handle an assignment TOVAL = FROMVAL by writing the value of
 177      FROMVAL to TOVAL's location.  The contents of TOVAL have not yet
 178      been updated.  If a problem arises in doing so, this function
 179      should call 'error'.  If it is NULL such TOVAL assignment is an error as
 180      TOVAL is not considered as an lvalue.  */
 181   void (*write) (struct value *toval, struct value *fromval);
 182
 183   /* Check the validity of some bits in VALUE.  This should return 1
 184      if all the bits starting at OFFSET and extending for LENGTH bits
 185      are valid, or 0 if any bit is invalid.  */
 186   int (*check_validity) (const struct value *value, int offset, int length);
 187
 188   /* Return 1 if any bit in VALUE is valid, 0 if they are all invalid.  */
 189   int (*check_any_valid) (const struct value *value);
 190
 191   /* If non-NULL, this is used to implement pointer indirection for
 192      this value.  This method may return NULL, in which case value_ind
 193      will fall back to ordinary indirection.  */
 194   struct value *(*indirect) (struct value *value);
 195
 196   /* If non-NULL, this is used to implement reference resolving for
 197      this value.  This method may return NULL, in which case coerce_ref
 198      will fall back to ordinary references resolving.  */
 199   struct value *(*coerce_ref) (const struct value *value);
 200
 201   /* If non-NULL, this is used to determine whether the indicated bits
 202      of VALUE are a synthetic pointer.  */
 203   int (*check_synthetic_pointer) (const struct value *value,
 204                                   int offset, int length);
 205
 206   /* Return a duplicate of VALUE's closure, for use in a new value.
 207      This may simply return the same closure, if VALUE's is
 208      reference-counted or statically allocated.
 209
 210      This may be NULL, in which case VALUE's closure is re-used in the
 211      new value.  */
 212   void *(*copy_closure) (const struct value *v);
 213
 214   /* Drop VALUE's reference to its closure.  Maybe this frees the
 215      closure; maybe this decrements a reference count; maybe the
 216      closure is statically allocated and this does nothing.
 217
 218      This may be NULL, in which case no action is taken to free
 219      VALUE's closure.  */
 220   void (*free_closure) (struct value *v);
 221 };
 222
 223 /* Create a computed lvalue, with type TYPE, function pointers FUNCS,
 224    and closure CLOSURE.  */
 225
 226 extern struct value *allocate_computed_value (struct type *type,
 227                                               const struct lval_funcs *funcs,
 228                                               void *closure);
 229
 230 /* Helper function to check the validity of some bits of a value.
 231
 232    If TYPE represents some aggregate type (e.g., a structure), return 1.
 233
 234    Otherwise, any of the bytes starting at OFFSET and extending for
 235    TYPE_LENGTH(TYPE) bytes are invalid, print a message to STREAM and
 236    return 0.  The checking is done using FUNCS.
 237
 238    Otherwise, return 1.  */
 239
 240 extern int valprint_check_validity (struct ui_file *stream, struct type *type,
 241                                     int embedded_offset,
 242                                     const struct value *val);
 243
 244 extern struct value *allocate_optimized_out_value (struct type *type);
 245
 246 /* If VALUE is lval_computed, return its lval_funcs structure.  */
 247
 248 extern const struct lval_funcs *value_computed_funcs (const struct value *);
 249
 250 /* If VALUE is lval_computed, return its closure.  The meaning of the
 251    returned value depends on the functions VALUE uses.  */
 252
 253 extern void *value_computed_closure (const struct value *value);
 254
 255 /* If zero, contents of this value are in the contents field.  If
 256    nonzero, contents are in inferior.  If the lval field is lval_memory,
 257    the contents are in inferior memory at location.address plus offset.
 258    The lval field may also be lval_register.
 259
 260    WARNING: This field is used by the code which handles watchpoints
 261    (see breakpoint.c) to decide whether a particular value can be
 262    watched by hardware watchpoints.  If the lazy flag is set for some
 263    member of a value chain, it is assumed that this member of the
 264    chain doesn't need to be watched as part of watching the value
 265    itself.  This is how GDB avoids watching the entire struct or array
 266    when the user wants to watch a single struct member or array
 267    element.  If you ever change the way lazy flag is set and reset, be
 268    sure to consider this use as well!  */
 269
 270 extern int value_lazy (struct value *);
 271 extern void set_value_lazy (struct value *value, int val);
 272
 273 extern int value_stack (struct value *);
 274 extern void set_value_stack (struct value *value, int val);
 275
 276 /* value_contents() and value_contents_raw() both return the address
 277    of the gdb buffer used to hold a copy of the contents of the lval.
 278    value_contents() is used when the contents of the buffer are needed
 279    -- it uses value_fetch_lazy() to load the buffer from the process
 280    being debugged if it hasn't already been loaded
 281    (value_contents_writeable() is used when a writeable but fetched
 282    buffer is required)..  value_contents_raw() is used when data is
 283    being stored into the buffer, or when it is certain that the
 284    contents of the buffer are valid.
 285
 286    Note: The contents pointer is adjusted by the offset required to
 287    get to the real subobject, if the value happens to represent
 288    something embedded in a larger run-time object.  */
 289
 290 extern gdb_byte *value_contents_raw (struct value *);
 291
 292 /* Actual contents of the value.  For use of this value; setting it
 293    uses the stuff above.  Not valid if lazy is nonzero.  Target
 294    byte-order.  We force it to be aligned properly for any possible
 295    value.  Note that a value therefore extends beyond what is
 296    declared here.  */
 297
 298 extern const gdb_byte *value_contents (struct value *);
 299 extern gdb_byte *value_contents_writeable (struct value *);
 300
 301 /* The ALL variants of the above two macros do not adjust the returned
 302    pointer by the embedded_offset value.  */
 303
 304 extern gdb_byte *value_contents_all_raw (struct value *);
 305 extern const gdb_byte *value_contents_all (struct value *);
 306
 307 /* Like value_contents_all, but does not require that the returned
 308    bits be valid.  This should only be used in situations where you
 309    plan to check the validity manually.  */
 310 extern const gdb_byte *value_contents_for_printing (struct value *value);
 311
 312 /* Like value_contents_for_printing, but accepts a constant value
 313    pointer.  Unlike value_contents_for_printing however, the pointed
 314    value must _not_ be lazy.  */
 315 extern const gdb_byte *
 316   value_contents_for_printing_const (const struct value *value);
 317
 318 extern int value_fetch_lazy (struct value *val);
 319 extern int value_contents_equal (struct value *val1, struct value *val2);
 320
 321 /* If nonzero, this is the value of a variable which does not actually
 322    exist in the program.  */
 323 extern int value_optimized_out (struct value *value);
 324 extern void set_value_optimized_out (struct value *value, int val);
 325
 326 /* Like value_optimized_out, but return false if any bit in the object
 327    is valid.  */
 328 extern int value_entirely_optimized_out (const struct value *value);
 329
 330 /* Set or return field indicating whether a variable is initialized or
 331    not, based on debugging information supplied by the compiler.
 332    1 = initialized; 0 = uninitialized.  */
 333 extern int value_initialized (struct value *);
 334 extern void set_value_initialized (struct value *, int);
 335
 336 /* Set COMPONENT's location as appropriate for a component of WHOLE
 337    --- regardless of what kind of lvalue WHOLE is.  */
 338 extern void set_value_component_location (struct value *component,
 339                                           const struct value *whole);
 340
 341 /* While the following fields are per- VALUE .CONTENT .PIECE (i.e., a
 342    single value might have multiple LVALs), this hacked interface is
 343    limited to just the first PIECE.  Expect further change.  */
 344 /* Type of value; either not an lval, or one of the various different
 345    possible kinds of lval.  */
 346 extern enum lval_type *deprecated_value_lval_hack (struct value *);
 347 #define VALUE_LVAL(val) (*deprecated_value_lval_hack (val))
 348
 349 /* Like VALUE_LVAL, except the parameter can be const.  */
 350 extern enum lval_type value_lval_const (const struct value *value);
 351
 352 /* If lval == lval_memory, return the address in the inferior.  If
 353    lval == lval_register, return the byte offset into the registers
 354    structure.  Otherwise, return 0.  The returned address
 355    includes the offset, if any.  */
 356 extern CORE_ADDR value_address (const struct value *);
 357
 358 /* Like value_address, except the result does not include value's
 359    offset.  */
 360 extern CORE_ADDR value_raw_address (struct value *);
 361
 362 /* Set the address of a value.  */
 363 extern void set_value_address (struct value *, CORE_ADDR);
 364
 365 /* Pointer to internal variable.  */
 366 extern struct internalvar **deprecated_value_internalvar_hack (struct value *);
 367 #define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val))
 368
 369 /* Frame register value is relative to.  This will be described in the
 370    lval enum above as "lval_register".  */
 371 extern struct frame_id *deprecated_value_frame_id_hack (struct value *);
 372 #define VALUE_FRAME_ID(val) (*deprecated_value_frame_id_hack (val))
 373
 374 /* Register number if the value is from a register.  */
 375 extern short *deprecated_value_regnum_hack (struct value *);
 376 #define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val))
 377
 378 /* Return value after lval_funcs->coerce_ref (after check_typedef).  Return
 379    NULL if lval_funcs->coerce_ref is not applicable for whatever reason.  */
 380
 381 extern struct value *coerce_ref_if_computed (const struct value *arg);
 382
 383 /* Setup a new value type and enclosing value type for dereferenced value VALUE.
 384    ENC_TYPE is the new enclosing type that should be set.  ORIGINAL_TYPE and
 385    ORIGINAL_VAL are the type and value of the original reference or pointer.
 386
 387    Note, that VALUE is modified by this function.
 388
 389    It is a common implementation for coerce_ref and value_ind.  */
 390
 391 extern struct value * readjust_indirect_value_type (struct value *value,
 392                                                     struct type *enc_type,
 393                                                     struct type *original_type,
 394                                                     struct value *original_val);
 395
 396 /* Convert a REF to the object referenced.  */
 397
 398 extern struct value *coerce_ref (struct value *value);
 399
 400 /* If ARG is an array, convert it to a pointer.
 401    If ARG is a function, convert it to a function pointer.
 402
 403    References are dereferenced.  */
 404
 405 extern struct value *coerce_array (struct value *value);
 406
 407 /* Given a value, determine whether the bits starting at OFFSET and
 408    extending for LENGTH bits are valid.  This returns nonzero if all
 409    bits in the given range are valid, zero if any bit is invalid.  */
 410
 411 extern int value_bits_valid (const struct value *value,
 412                              int offset, int length);
 413
 414 /* Given a value, determine whether the bits starting at OFFSET and
 415    extending for LENGTH bits are a synthetic pointer.  */
 416
 417 extern int value_bits_synthetic_pointer (const struct value *value,
 418                                          int offset, int length);
 419
 420 /* Given a value, determine whether the contents bytes starting at
 421    OFFSET and extending for LENGTH bytes are available.  This returns
 422    nonzero if all bytes in the given range are available, zero if any
 423    byte is unavailable.  */
 424
 425 extern int value_bytes_available (const struct value *value,
 426                                   int offset, int length);
 427
 428 /* Like value_bytes_available, but return false if any byte in the
 429    whole object is unavailable.  */
 430 extern int value_entirely_available (struct value *value);
 431
 432 /* Mark VALUE's content bytes starting at OFFSET and extending for
 433    LENGTH bytes as unavailable.  */
 434
 435 extern void mark_value_bytes_unavailable (struct value *value,
 436                                           int offset, int length);
 437
 438 /* Compare LENGTH bytes of VAL1's contents starting at OFFSET1 with
 439    LENGTH bytes of VAL2's contents starting at OFFSET2.
 440
 441    Note that "contents" refers to the whole value's contents
 442    (value_contents_all), without any embedded offset adjustment.  For
 443    example, to compare a complete object value with itself, including
 444    its enclosing type chunk, you'd do:
 445
 446      int len = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
 447      value_available_contents (val, 0, val, 0, len);
 448
 449    Returns true iff the set of available contents match.  Unavailable
 450    contents compare equal with unavailable contents, and different
 451    with any available byte.  For example, if 'x's represent an
 452    unavailable byte, and 'V' and 'Z' represent different available
 453    bytes, in a value with length 16:
 454
 455    offset:   0   4   8   12  16
 456    contents: xxxxVVVVxxxxVVZZ
 457
 458    then:
 459
 460    value_available_contents_eq(val, 0, val, 8, 6) => 1
 461    value_available_contents_eq(val, 0, val, 4, 4) => 1
 462    value_available_contents_eq(val, 0, val, 8, 8) => 0
 463    value_available_contents_eq(val, 4, val, 12, 2) => 1
 464    value_available_contents_eq(val, 4, val, 12, 4) => 0
 465    value_available_contents_eq(val, 3, val, 4, 4) => 0
 466 */
 467
 468 extern int value_available_contents_eq (const struct value *val1, int offset1,
 469                                         const struct value *val2, int offset2,
 470                                         int length);
 471
 472 /* Read LENGTH bytes of memory starting at MEMADDR into BUFFER, which
 473    is (or will be copied to) VAL's contents buffer offset by
 474    EMBEDDED_OFFSET (that is, to &VAL->contents[EMBEDDED_OFFSET]).
 475    Marks value contents ranges as unavailable if the corresponding
 476    memory is likewise unavailable.  STACK indicates whether the memory
 477    is known to be stack memory.  */
 478
 479 extern void read_value_memory (struct value *val, int embedded_offset,
 480                                int stack, CORE_ADDR memaddr,
 481                                gdb_byte *buffer, size_t length);
 482
 483 /* Cast SCALAR_VALUE to the element type of VECTOR_TYPE, then replicate
 484    into each element of a new vector value with VECTOR_TYPE.  */
 485
 486 struct value *value_vector_widen (struct value *scalar_value,
 487                                   struct type *vector_type);
 488
 489 \f
 490
 491 #include "symtab.h"
 492 #include "gdbtypes.h"
 493 #include "expression.h"
 494
 495 struct frame_info;
 496 struct fn_field;
 497
 498 extern int print_address_demangle (const struct value_print_options *,
 499                                    struct gdbarch *, CORE_ADDR,
 500                                    struct ui_file *, int);
 501
 502 extern LONGEST value_as_long (struct value *val);
 503 extern DOUBLEST value_as_double (struct value *val);
 504 extern CORE_ADDR value_as_address (struct value *val);
 505
 506 extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr);
 507 extern DOUBLEST unpack_double (struct type *type, const gdb_byte *valaddr,
 508                                int *invp);
 509 extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr);
 510
 511 extern int unpack_value_bits_as_long (struct type *field_type,
 512                                       const gdb_byte *valaddr,
 513                                       int embedded_offset, int bitpos,
 514                                       int bitsize,
 515                                       const struct value *original_value,
 516                                       LONGEST *result);
 517
 518 extern LONGEST unpack_field_as_long (struct type *type,
 519                                      const gdb_byte *valaddr,
 520                                      int fieldno);
 521 extern int unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr,
 522                                 int embedded_offset, int fieldno,
 523                                 const struct value *val, LONGEST *result);
 524
 525 extern struct value *value_field_bitfield (struct type *type, int fieldno,
 526                                            const gdb_byte *valaddr,
 527                                            int embedded_offset,
 528                                            const struct value *val);
 529
 530 extern void pack_long (gdb_byte *buf, struct type *type, LONGEST num);
 531
 532 extern struct value *value_from_longest (struct type *type, LONGEST num);
 533 extern struct value *value_from_ulongest (struct type *type, ULONGEST num);
 534 extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr);
 535 extern struct value *value_from_double (struct type *type, DOUBLEST num);
 536 extern struct value *value_from_decfloat (struct type *type,
 537                                           const gdb_byte *decbytes);
 538 extern struct value *value_from_history_ref (char *, char **);
 539
 540 extern struct value *value_at (struct type *type, CORE_ADDR addr);
 541 extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr);
 542
 543 extern struct value *value_from_contents_and_address (struct type *,
 544                                                       const gdb_byte *,
 545                                                       CORE_ADDR);
 546 extern struct value *value_from_contents (struct type *, const gdb_byte *);
 547
 548 extern struct value *default_value_from_register (struct type *type,
 549                                                   int regnum,
 550                                                   struct frame_info *frame);
 551
 552 extern void read_frame_register_value (struct value *value,
 553                                        struct frame_info *frame);
 554
 555 extern struct value *value_from_register (struct type *type, int regnum,
 556                                           struct frame_info *frame);
 557
 558 extern CORE_ADDR address_from_register (struct type *type, int regnum,
 559                                         struct frame_info *frame);
 560
 561 extern struct value *value_of_variable (struct symbol *var,
 562                                         const struct block *b);
 563
 564 extern struct value *address_of_variable (struct symbol *var,
 565                                           const struct block *b);
 566
 567 extern struct value *value_of_register (int regnum, struct frame_info *frame);
 568
 569 struct value *value_of_register_lazy (struct frame_info *frame, int regnum);
 570
 571 extern int symbol_read_needs_frame (struct symbol *);
 572
 573 extern struct value *read_var_value (struct symbol *var,
 574                                      struct frame_info *frame);
 575
 576 extern struct value *default_read_var_value (struct symbol *var,
 577                                              struct frame_info *frame);
 578
 579 extern struct value *allocate_value (struct type *type);
 580 extern struct value *allocate_value_lazy (struct type *type);
 581 extern void allocate_value_contents (struct value *value);
 582 extern void value_contents_copy (struct value *dst, int dst_offset,
 583                                  struct value *src, int src_offset,
 584                                  int length);
 585 extern void value_contents_copy_raw (struct value *dst, int dst_offset,
 586                                      struct value *src, int src_offset,
 587                                      int length);
 588
 589 extern struct value *allocate_repeat_value (struct type *type, int count);
 590
 591 extern struct value *value_mark (void);
 592
 593 extern void value_free_to_mark (struct value *mark);
 594
 595 extern struct value *value_cstring (char *ptr, ssize_t len,
 596                                     struct type *char_type);
 597 extern struct value *value_string (char *ptr, ssize_t len,
 598                                    struct type *char_type);
 599
 600 extern struct value *value_array (int lowbound, int highbound,
 601                                   struct value **elemvec);
 602
 603 extern struct value *value_concat (struct value *arg1, struct value *arg2);
 604
 605 extern struct value *value_binop (struct value *arg1, struct value *arg2,
 606                                   enum exp_opcode op);
 607
 608 extern struct value *value_ptradd (struct value *arg1, LONGEST arg2);
 609
 610 extern LONGEST value_ptrdiff (struct value *arg1, struct value *arg2);
 611
 612 extern int value_must_coerce_to_target (struct value *arg1);
 613
 614 extern struct value *value_coerce_to_target (struct value *arg1);
 615
 616 extern struct value *value_coerce_array (struct value *arg1);
 617
 618 extern struct value *value_coerce_function (struct value *arg1);
 619
 620 extern struct value *value_ind (struct value *arg1);
 621
 622 extern struct value *value_addr (struct value *arg1);
 623
 624 extern struct value *value_ref (struct value *arg1);
 625
 626 extern struct value *value_assign (struct value *toval,
 627                                    struct value *fromval);
 628
 629 extern struct value *value_pos (struct value *arg1);
 630
 631 extern struct value *value_neg (struct value *arg1);
 632
 633 extern struct value *value_complement (struct value *arg1);
 634
 635 extern struct value *value_struct_elt (struct value **argp,
 636                                        struct value **args,
 637                                        const char *name, int *static_memfuncp,
 638                                        const char *err);
 639
 640 extern struct value *value_aggregate_elt (struct type *curtype,
 641                                           char *name,
 642                                           struct type *expect_type,
 643                                           int want_address,
 644                                           enum noside noside);
 645
 646 extern struct value *value_static_field (struct type *type, int fieldno);
 647
 648 enum oload_search_type { NON_METHOD, METHOD, BOTH };
 649
 650 extern int find_overload_match (struct value **args, int nargs,
 651                                 const char *name,
 652                                 enum oload_search_type method,
 653                                 struct value **objp, struct symbol *fsym,
 654                                 struct value **valp, struct symbol **symp,
 655                                 int *staticp, const int no_adl);
 656
 657 extern struct value *value_field (struct value *arg1, int fieldno);
 658
 659 extern struct value *value_primitive_field (struct value *arg1, int offset,
 660                                             int fieldno,
 661                                             struct type *arg_type);
 662
 663
 664 extern struct type *value_rtti_indirect_type (struct value *, int *, int *,
 665                                               int *);
 666
 667 extern struct value *value_full_object (struct value *, struct type *, int,
 668                                         int, int);
 669
 670 extern struct value *value_cast_pointers (struct type *, struct value *, int);
 671
 672 extern struct value *value_cast (struct type *type, struct value *arg2);
 673
 674 extern struct value *value_reinterpret_cast (struct type *type,
 675                                              struct value *arg);
 676
 677 extern struct value *value_dynamic_cast (struct type *type, struct value *arg);
 678
 679 extern struct value *value_zero (struct type *type, enum lval_type lv);
 680
 681 extern struct value *value_one (struct type *type);
 682
 683 extern struct value *value_repeat (struct value *arg1, int count);
 684
 685 extern struct value *value_subscript (struct value *array, LONGEST index);
 686
 687 extern struct value *value_bitstring_subscript (struct type *type,
 688                                                 struct value *bitstring,
 689                                                 LONGEST index);
 690
 691 extern struct value *register_value_being_returned (struct type *valtype,
 692                                                     struct regcache *retbuf);
 693
 694 extern int value_in (struct value *element, struct value *set);
 695
 696 extern int value_bit_index (struct type *type, const gdb_byte *addr,
 697                             int index);
 698
 699 extern enum return_value_convention
 700 struct_return_convention (struct gdbarch *gdbarch, struct value *function,
 701                           struct type *value_type);
 702
 703 extern int using_struct_return (struct gdbarch *gdbarch,
 704                                 struct value *function,
 705                                 struct type *value_type);
 706
 707 extern struct value *evaluate_expression (struct expression *exp);
 708
 709 extern struct value *evaluate_type (struct expression *exp);
 710
 711 extern struct value *evaluate_subexp (struct type *expect_type,
 712                                       struct expression *exp,
 713                                       int *pos, enum noside noside);
 714
 715 extern struct value *evaluate_subexpression_type (struct expression *exp,
 716                                                   int subexp);
 717
 718 extern void fetch_subexp_value (struct expression *exp, int *pc,
 719                                 struct value **valp, struct value **resultp,
 720                                 struct value **val_chain);
 721
 722 extern char *extract_field_op (struct expression *exp, int *subexp);
 723
 724 extern struct value *evaluate_subexp_with_coercion (struct expression *,
 725                                                     int *, enum noside);
 726
 727 extern struct value *parse_and_eval (const char *exp);
 728
 729 extern struct value *parse_to_comma_and_eval (const char **expp);
 730
 731 extern struct type *parse_and_eval_type (char *p, int length);
 732
 733 extern CORE_ADDR parse_and_eval_address (const char *exp);
 734
 735 extern LONGEST parse_and_eval_long (char *exp);
 736
 737 extern void unop_promote (const struct language_defn *language,
 738                           struct gdbarch *gdbarch,
 739                           struct value **arg1);
 740
 741 extern void binop_promote (const struct language_defn *language,
 742                            struct gdbarch *gdbarch,
 743                            struct value **arg1, struct value **arg2);
 744
 745 extern struct value *access_value_history (int num);
 746
 747 extern struct value *value_of_internalvar (struct gdbarch *gdbarch,
 748                                            struct internalvar *var);
 749
 750 extern int get_internalvar_integer (struct internalvar *var, LONGEST *l);
 751
 752 extern void set_internalvar (struct internalvar *var, struct value *val);
 753
 754 extern void set_internalvar_integer (struct internalvar *var, LONGEST l);
 755
 756 extern void set_internalvar_string (struct internalvar *var,
 757                                     const char *string);
 758
 759 extern void clear_internalvar (struct internalvar *var);
 760
 761 extern void set_internalvar_component (struct internalvar *var,
 762                                        int offset,
 763                                        int bitpos, int bitsize,
 764                                        struct value *newvalue);
 765
 766 extern struct internalvar *lookup_only_internalvar (const char *name);
 767
 768 extern struct internalvar *create_internalvar (const char *name);
 769
 770 extern VEC (char_ptr) *complete_internalvar (const char *name);
 771
 772 /* An internalvar can be dynamically computed by supplying a vector of
 773    function pointers to perform various operations.  */
 774
 775 struct internalvar_funcs
 776 {
 777   /* Compute the value of the variable.  The DATA argument passed to
 778      the function is the same argument that was passed to
 779      `create_internalvar_type_lazy'.  */
 780
 781   struct value *(*make_value) (struct gdbarch *arch,
 782                                struct internalvar *var,
 783                                void *data);
 784
 785   /* Update the agent expression EXPR with bytecode to compute the
 786      value.  VALUE is the agent value we are updating.  The DATA
 787      argument passed to this function is the same argument that was
 788      passed to `create_internalvar_type_lazy'.  If this pointer is
 789      NULL, then the internalvar cannot be compiled to an agent
 790      expression.  */
 791
 792   void (*compile_to_ax) (struct internalvar *var,
 793                          struct agent_expr *expr,
 794                          struct axs_value *value,
 795                          void *data);
 796
 797   /* If non-NULL, this is called to destroy DATA.  The DATA argument
 798      passed to this function is the same argument that was passed to
 799      `create_internalvar_type_lazy'.  */
 800
 801   void (*destroy) (void *data);
 802 };
 803
 804 extern struct internalvar *
 805 create_internalvar_type_lazy (const char *name,
 806                               const struct internalvar_funcs *funcs,
 807                               void *data);
 808
 809 /* Compile an internal variable to an agent expression.  VAR is the
 810    variable to compile; EXPR and VALUE are the agent expression we are
 811    updating.  This will return 0 if there is no known way to compile
 812    VAR, and 1 if VAR was successfully compiled.  It may also throw an
 813    exception on error.  */
 814
 815 extern int compile_internalvar_to_ax (struct internalvar *var,
 816                                       struct agent_expr *expr,
 817                                       struct axs_value *value);
 818
 819 extern struct internalvar *lookup_internalvar (const char *name);
 820
 821 extern int value_equal (struct value *arg1, struct value *arg2);
 822
 823 extern int value_equal_contents (struct value *arg1, struct value *arg2);
 824
 825 extern int value_less (struct value *arg1, struct value *arg2);
 826
 827 extern int value_logical_not (struct value *arg1);
 828
 829 /* C++ */
 830
 831 extern struct value *value_of_this (const struct language_defn *lang);
 832
 833 extern struct value *value_of_this_silent (const struct language_defn *lang);
 834
 835 extern struct value *value_x_binop (struct value *arg1, struct value *arg2,
 836                                     enum exp_opcode op,
 837                                     enum exp_opcode otherop,
 838                                     enum noside noside);
 839
 840 extern struct value *value_x_unop (struct value *arg1, enum exp_opcode op,
 841                                    enum noside noside);
 842
 843 extern struct value *value_fn_field (struct value **arg1p, struct fn_field *f,
 844                                      int j, struct type *type, int offset);
 845
 846 extern int binop_types_user_defined_p (enum exp_opcode op,
 847                                        struct type *type1,
 848                                        struct type *type2);
 849
 850 extern int binop_user_defined_p (enum exp_opcode op, struct value *arg1,
 851                                  struct value *arg2);
 852
 853 extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1);
 854
 855 extern int destructor_name_p (const char *name, struct type *type);
 856
 857 extern void value_incref (struct value *val);
 858
 859 extern void value_free (struct value *val);
 860
 861 extern void free_all_values (void);
 862
 863 extern void free_value_chain (struct value *v);
 864
 865 extern void release_value (struct value *val);
 866
 867 extern void release_value_or_incref (struct value *val);
 868
 869 extern int record_latest_value (struct value *val);
 870
 871 extern void modify_field (struct type *type, gdb_byte *addr,
 872                           LONGEST fieldval, int bitpos, int bitsize);
 873
 874 extern void type_print (struct type *type, const char *varstring,
 875                         struct ui_file *stream, int show);
 876
 877 extern char *type_to_string (struct type *type);
 878
 879 extern gdb_byte *baseclass_addr (struct type *type, int index,
 880                                  gdb_byte *valaddr,
 881                                  struct value **valuep, int *errp);
 882
 883 extern void print_longest (struct ui_file *stream, int format,
 884                            int use_local, LONGEST val);
 885
 886 extern void print_floating (const gdb_byte *valaddr, struct type *type,
 887                             struct ui_file *stream);
 888
 889 extern void print_decimal_floating (const gdb_byte *valaddr, struct type *type,
 890                                     struct ui_file *stream);
 891
 892 extern void value_print (struct value *val, struct ui_file *stream,
 893                          const struct value_print_options *options);
 894
 895 extern void value_print_array_elements (struct value *val,
 896                                         struct ui_file *stream, int format,
 897                                         enum val_prettyprint pretty);
 898
 899 extern struct value *value_release_to_mark (struct value *mark);
 900
 901 extern void val_print (struct type *type, const gdb_byte *valaddr,
 902                        int embedded_offset, CORE_ADDR address,
 903                        struct ui_file *stream, int recurse,
 904                        const struct value *val,
 905                        const struct value_print_options *options,
 906                        const struct language_defn *language);
 907
 908 extern void common_val_print (struct value *val,
 909                               struct ui_file *stream, int recurse,
 910                               const struct value_print_options *options,
 911                               const struct language_defn *language);
 912
 913 extern int val_print_string (struct type *elttype, const char *encoding,
 914                              CORE_ADDR addr, int len,
 915                              struct ui_file *stream,
 916                              const struct value_print_options *options);
 917
 918 extern void print_variable_and_value (const char *name,
 919                                       struct symbol *var,
 920                                       struct frame_info *frame,
 921                                       struct ui_file *stream,
 922                                       int indent);
 923
 924 extern void typedef_print (struct type *type, struct symbol *news,
 925                            struct ui_file *stream);
 926
 927 extern char *internalvar_name (struct internalvar *var);
 928
 929 extern void preserve_values (struct objfile *);
 930
 931 /* From values.c */
 932
 933 extern struct value *value_copy (struct value *);
 934
 935 extern struct value *value_non_lval (struct value *);
 936
 937 extern void preserve_one_value (struct value *, struct objfile *, htab_t);
 938
 939 /* From valops.c */
 940
 941 extern struct value *varying_to_slice (struct value *);
 942
 943 extern struct value *value_slice (struct value *, int, int);
 944
 945 extern struct value *value_literal_complex (struct value *, struct value *,
 946                                             struct type *);
 947
 948 extern struct value *find_function_in_inferior (const char *,
 949                                                 struct objfile **);
 950
 951 extern struct value *value_allocate_space_in_inferior (int);
 952
 953 extern struct value *value_subscripted_rvalue (struct value *array,
 954                                                LONGEST index, int lowerbound);
 955
 956 /* User function handler.  */
 957
 958 typedef struct value *(*internal_function_fn) (struct gdbarch *gdbarch,
 959                                                const struct language_defn *language,
 960                                                void *cookie,
 961                                                int argc,
 962                                                struct value **argv);
 963
 964 void add_internal_function (const char *name, const char *doc,
 965                             internal_function_fn handler,
 966                             void *cookie);
 967
 968 struct value *call_internal_function (struct gdbarch *gdbarch,
 969                                       const struct language_defn *language,
 970                                       struct value *function,
 971                                       int argc, struct value **argv);
 972
 973 char *value_internal_function_name (struct value *);
 974
 975 #endif /* !defined (VALUE_H) */