value.h revision 1.1.1.4
1 /* Definitions for values of C expressions, for GDB. 2 3 Copyright (C) 1986-2016 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 struct xmethod_worker; 35 36 /* Values can be partially 'optimized out' and/or 'unavailable'. 37 These are distinct states and have different string representations 38 and related error strings. 39 40 'unavailable' has a specific meaning in this context. It means the 41 value exists in the program (at the machine level), but GDB has no 42 means to get to it. Such a value is normally printed as 43 <unavailable>. Examples of how to end up with an unavailable value 44 would be: 45 46 - We're inspecting a traceframe, and the memory or registers the 47 debug information says the value lives on haven't been collected. 48 49 - We're inspecting a core dump, the memory or registers the debug 50 information says the value lives aren't present in the dump 51 (that is, we have a partial/trimmed core dump, or we don't fully 52 understand/handle the core dump's format). 53 54 - We're doing live debugging, but the debug API has no means to 55 get at where the value lives in the machine, like e.g., ptrace 56 not having access to some register or register set. 57 58 - Any other similar scenario. 59 60 OTOH, "optimized out" is about what the compiler decided to generate 61 (or not generate). A chunk of a value that was optimized out does 62 not actually exist in the program. There's no way to get at it 63 short of compiling the program differently. 64 65 A register that has not been saved in a frame is likewise considered 66 optimized out, except not-saved registers have a different string 67 representation and related error strings. E.g., we'll print them as 68 <not-saved> instead of <optimized out>, as in: 69 70 (gdb) p/x $rax 71 $1 = <not saved> 72 (gdb) info registers rax 73 rax <not saved> 74 75 If the debug info describes a variable as being in such a register, 76 we'll still print the variable as <optimized out>. IOW, <not saved> 77 is reserved for inspecting registers at the machine level. 78 79 When comparing value contents, optimized out chunks, unavailable 80 chunks, and valid contents data are all considered different. See 81 value_contents_eq for more info. 82 */ 83 84 /* The structure which defines the type of a value. It should never 85 be possible for a program lval value to survive over a call to the 86 inferior (i.e. to be put into the history list or an internal 87 variable). */ 88 89 struct value; 90 91 /* Values are stored in a chain, so that they can be deleted easily 92 over calls to the inferior. Values assigned to internal variables, 93 put into the value history or exposed to Python are taken off this 94 list. */ 95 96 struct value *value_next (const struct value *); 97 98 /* Type of the value. */ 99 100 extern struct type *value_type (const struct value *); 101 102 /* Return the gdbarch associated with the value. */ 103 104 extern struct gdbarch *get_value_arch (const struct value *value); 105 106 /* This is being used to change the type of an existing value, that 107 code should instead be creating a new value with the changed type 108 (but possibly shared content). */ 109 110 extern void deprecated_set_value_type (struct value *value, 111 struct type *type); 112 113 /* Only used for bitfields; number of bits contained in them. */ 114 115 extern LONGEST value_bitsize (const struct value *); 116 extern void set_value_bitsize (struct value *, LONGEST bit); 117 118 /* Only used for bitfields; position of start of field. For 119 gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For 120 gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */ 121 122 extern LONGEST value_bitpos (const struct value *); 123 extern void set_value_bitpos (struct value *, LONGEST bit); 124 125 /* Only used for bitfields; the containing value. This allows a 126 single read from the target when displaying multiple 127 bitfields. */ 128 129 struct value *value_parent (const struct value *); 130 extern void set_value_parent (struct value *value, struct value *parent); 131 132 /* Describes offset of a value within lval of a structure in bytes. 133 If lval == lval_memory, this is an offset to the address. If lval 134 == lval_register, this is a further offset from location.address 135 within the registers structure. Note also the member 136 embedded_offset below. */ 137 138 extern LONGEST value_offset (const struct value *); 139 extern void set_value_offset (struct value *, LONGEST offset); 140 141 /* The comment from "struct value" reads: ``Is it modifiable? Only 142 relevant if lval != not_lval.''. Shouldn't the value instead be 143 not_lval and be done with it? */ 144 145 extern int deprecated_value_modifiable (const struct value *value); 146 147 /* If a value represents a C++ object, then the `type' field gives the 148 object's compile-time type. If the object actually belongs to some 149 class derived from `type', perhaps with other base classes and 150 additional members, then `type' is just a subobject of the real 151 thing, and the full object is probably larger than `type' would 152 suggest. 153 154 If `type' is a dynamic class (i.e. one with a vtable), then GDB can 155 actually determine the object's run-time type by looking at the 156 run-time type information in the vtable. When this information is 157 available, we may elect to read in the entire object, for several 158 reasons: 159 160 - When printing the value, the user would probably rather see the 161 full object, not just the limited portion apparent from the 162 compile-time type. 163 164 - If `type' has virtual base classes, then even printing `type' 165 alone may require reaching outside the `type' portion of the 166 object to wherever the virtual base class has been stored. 167 168 When we store the entire object, `enclosing_type' is the run-time 169 type -- the complete object -- and `embedded_offset' is the offset 170 of `type' within that larger type, in bytes. The value_contents() 171 macro takes `embedded_offset' into account, so most GDB code 172 continues to see the `type' portion of the value, just as the 173 inferior would. 174 175 If `type' is a pointer to an object, then `enclosing_type' is a 176 pointer to the object's run-time type, and `pointed_to_offset' is 177 the offset in bytes from the full object to the pointed-to object 178 -- that is, the value `embedded_offset' would have if we followed 179 the pointer and fetched the complete object. (I don't really see 180 the point. Why not just determine the run-time type when you 181 indirect, and avoid the special case? The contents don't matter 182 until you indirect anyway.) 183 184 If we're not doing anything fancy, `enclosing_type' is equal to 185 `type', and `embedded_offset' is zero, so everything works 186 normally. */ 187 188 extern struct type *value_enclosing_type (const struct value *); 189 extern void set_value_enclosing_type (struct value *val, 190 struct type *new_type); 191 192 /* Returns value_type or value_enclosing_type depending on 193 value_print_options.objectprint. 194 195 If RESOLVE_SIMPLE_TYPES is 0 the enclosing type will be resolved 196 only for pointers and references, else it will be returned 197 for all the types (e.g. structures). This option is useful 198 to prevent retrieving enclosing type for the base classes fields. 199 200 REAL_TYPE_FOUND is used to inform whether the real type was found 201 (or just static type was used). The NULL may be passed if it is not 202 necessary. */ 203 204 extern struct type *value_actual_type (struct value *value, 205 int resolve_simple_types, 206 int *real_type_found); 207 208 extern LONGEST value_pointed_to_offset (const struct value *value); 209 extern void set_value_pointed_to_offset (struct value *value, LONGEST val); 210 extern LONGEST value_embedded_offset (const struct value *value); 211 extern void set_value_embedded_offset (struct value *value, LONGEST val); 212 213 /* For lval_computed values, this structure holds functions used to 214 retrieve and set the value (or portions of the value). 215 216 For each function, 'V' is the 'this' pointer: an lval_funcs 217 function F may always assume that the V it receives is an 218 lval_computed value, and has F in the appropriate slot of its 219 lval_funcs structure. */ 220 221 struct lval_funcs 222 { 223 /* Fill in VALUE's contents. This is used to "un-lazy" values. If 224 a problem arises in obtaining VALUE's bits, this function should 225 call 'error'. If it is NULL value_fetch_lazy on "un-lazy" 226 non-optimized-out value is an internal error. */ 227 void (*read) (struct value *v); 228 229 /* Handle an assignment TOVAL = FROMVAL by writing the value of 230 FROMVAL to TOVAL's location. The contents of TOVAL have not yet 231 been updated. If a problem arises in doing so, this function 232 should call 'error'. If it is NULL such TOVAL assignment is an error as 233 TOVAL is not considered as an lvalue. */ 234 void (*write) (struct value *toval, struct value *fromval); 235 236 /* If non-NULL, this is used to implement pointer indirection for 237 this value. This method may return NULL, in which case value_ind 238 will fall back to ordinary indirection. */ 239 struct value *(*indirect) (struct value *value); 240 241 /* If non-NULL, this is used to implement reference resolving for 242 this value. This method may return NULL, in which case coerce_ref 243 will fall back to ordinary references resolving. */ 244 struct value *(*coerce_ref) (const struct value *value); 245 246 /* If non-NULL, this is used to determine whether the indicated bits 247 of VALUE are a synthetic pointer. */ 248 int (*check_synthetic_pointer) (const struct value *value, 249 LONGEST offset, int length); 250 251 /* Return a duplicate of VALUE's closure, for use in a new value. 252 This may simply return the same closure, if VALUE's is 253 reference-counted or statically allocated. 254 255 This may be NULL, in which case VALUE's closure is re-used in the 256 new value. */ 257 void *(*copy_closure) (const struct value *v); 258 259 /* Drop VALUE's reference to its closure. Maybe this frees the 260 closure; maybe this decrements a reference count; maybe the 261 closure is statically allocated and this does nothing. 262 263 This may be NULL, in which case no action is taken to free 264 VALUE's closure. */ 265 void (*free_closure) (struct value *v); 266 }; 267 268 /* Create a computed lvalue, with type TYPE, function pointers FUNCS, 269 and closure CLOSURE. */ 270 271 extern struct value *allocate_computed_value (struct type *type, 272 const struct lval_funcs *funcs, 273 void *closure); 274 275 /* Helper function to check the validity of some bits of a value. 276 277 If TYPE represents some aggregate type (e.g., a structure), return 1. 278 279 Otherwise, any of the bytes starting at OFFSET and extending for 280 TYPE_LENGTH(TYPE) bytes are invalid, print a message to STREAM and 281 return 0. The checking is done using FUNCS. 282 283 Otherwise, return 1. */ 284 285 extern int valprint_check_validity (struct ui_file *stream, struct type *type, 286 LONGEST embedded_offset, 287 const struct value *val); 288 289 extern struct value *allocate_optimized_out_value (struct type *type); 290 291 /* If VALUE is lval_computed, return its lval_funcs structure. */ 292 293 extern const struct lval_funcs *value_computed_funcs (const struct value *); 294 295 /* If VALUE is lval_computed, return its closure. The meaning of the 296 returned value depends on the functions VALUE uses. */ 297 298 extern void *value_computed_closure (const struct value *value); 299 300 /* If zero, contents of this value are in the contents field. If 301 nonzero, contents are in inferior. If the lval field is lval_memory, 302 the contents are in inferior memory at location.address plus offset. 303 The lval field may also be lval_register. 304 305 WARNING: This field is used by the code which handles watchpoints 306 (see breakpoint.c) to decide whether a particular value can be 307 watched by hardware watchpoints. If the lazy flag is set for some 308 member of a value chain, it is assumed that this member of the 309 chain doesn't need to be watched as part of watching the value 310 itself. This is how GDB avoids watching the entire struct or array 311 when the user wants to watch a single struct member or array 312 element. If you ever change the way lazy flag is set and reset, be 313 sure to consider this use as well! */ 314 315 extern int value_lazy (const struct value *); 316 extern void set_value_lazy (struct value *value, int val); 317 318 extern int value_stack (const struct value *); 319 extern void set_value_stack (struct value *value, int val); 320 321 /* Throw an error complaining that the value has been optimized 322 out. */ 323 324 extern void error_value_optimized_out (void); 325 326 /* value_contents() and value_contents_raw() both return the address 327 of the gdb buffer used to hold a copy of the contents of the lval. 328 value_contents() is used when the contents of the buffer are needed 329 -- it uses value_fetch_lazy() to load the buffer from the process 330 being debugged if it hasn't already been loaded 331 (value_contents_writeable() is used when a writeable but fetched 332 buffer is required).. value_contents_raw() is used when data is 333 being stored into the buffer, or when it is certain that the 334 contents of the buffer are valid. 335 336 Note: The contents pointer is adjusted by the offset required to 337 get to the real subobject, if the value happens to represent 338 something embedded in a larger run-time object. */ 339 340 extern gdb_byte *value_contents_raw (struct value *); 341 342 /* Actual contents of the value. For use of this value; setting it 343 uses the stuff above. Not valid if lazy is nonzero. Target 344 byte-order. We force it to be aligned properly for any possible 345 value. Note that a value therefore extends beyond what is 346 declared here. */ 347 348 extern const gdb_byte *value_contents (struct value *); 349 extern gdb_byte *value_contents_writeable (struct value *); 350 351 /* The ALL variants of the above two macros do not adjust the returned 352 pointer by the embedded_offset value. */ 353 354 extern gdb_byte *value_contents_all_raw (struct value *); 355 extern const gdb_byte *value_contents_all (struct value *); 356 357 /* Like value_contents_all, but does not require that the returned 358 bits be valid. This should only be used in situations where you 359 plan to check the validity manually. */ 360 extern const gdb_byte *value_contents_for_printing (struct value *value); 361 362 /* Like value_contents_for_printing, but accepts a constant value 363 pointer. Unlike value_contents_for_printing however, the pointed 364 value must _not_ be lazy. */ 365 extern const gdb_byte * 366 value_contents_for_printing_const (const struct value *value); 367 368 extern void value_fetch_lazy (struct value *val); 369 370 /* If nonzero, this is the value of a variable which does not actually 371 exist in the program, at least partially. If the value is lazy, 372 this may fetch it now. */ 373 extern int value_optimized_out (struct value *value); 374 375 /* Given a value, return true if any of the contents bits starting at 376 OFFSET and extending for LENGTH bits is optimized out, false 377 otherwise. */ 378 379 extern int value_bits_any_optimized_out (const struct value *value, 380 int bit_offset, int bit_length); 381 382 /* Like value_optimized_out, but return true iff the whole value is 383 optimized out. */ 384 extern int value_entirely_optimized_out (struct value *value); 385 386 /* Mark VALUE's content bytes starting at OFFSET and extending for 387 LENGTH bytes as optimized out. */ 388 389 extern void mark_value_bytes_optimized_out (struct value *value, 390 int offset, int length); 391 392 /* Mark VALUE's content bits starting at OFFSET and extending for 393 LENGTH bits as optimized out. */ 394 395 extern void mark_value_bits_optimized_out (struct value *value, 396 LONGEST offset, LONGEST length); 397 398 /* Set or return field indicating whether a variable is initialized or 399 not, based on debugging information supplied by the compiler. 400 1 = initialized; 0 = uninitialized. */ 401 extern int value_initialized (const struct value *); 402 extern void set_value_initialized (struct value *, int); 403 404 /* Set COMPONENT's location as appropriate for a component of WHOLE 405 --- regardless of what kind of lvalue WHOLE is. */ 406 extern void set_value_component_location (struct value *component, 407 const struct value *whole); 408 409 /* While the following fields are per- VALUE .CONTENT .PIECE (i.e., a 410 single value might have multiple LVALs), this hacked interface is 411 limited to just the first PIECE. Expect further change. */ 412 /* Type of value; either not an lval, or one of the various different 413 possible kinds of lval. */ 414 extern enum lval_type *deprecated_value_lval_hack (struct value *); 415 #define VALUE_LVAL(val) (*deprecated_value_lval_hack (val)) 416 417 /* Like VALUE_LVAL, except the parameter can be const. */ 418 extern enum lval_type value_lval_const (const struct value *value); 419 420 /* If lval == lval_memory, return the address in the inferior. If 421 lval == lval_register, return the byte offset into the registers 422 structure. Otherwise, return 0. The returned address 423 includes the offset, if any. */ 424 extern CORE_ADDR value_address (const struct value *); 425 426 /* Like value_address, except the result does not include value's 427 offset. */ 428 extern CORE_ADDR value_raw_address (const struct value *); 429 430 /* Set the address of a value. */ 431 extern void set_value_address (struct value *, CORE_ADDR); 432 433 /* Pointer to internal variable. */ 434 extern struct internalvar **deprecated_value_internalvar_hack (struct value *); 435 #define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val)) 436 437 /* Frame register value is relative to. This will be described in the 438 lval enum above as "lval_register". */ 439 extern struct frame_id *deprecated_value_frame_id_hack (struct value *); 440 #define VALUE_FRAME_ID(val) (*deprecated_value_frame_id_hack (val)) 441 442 /* Register number if the value is from a register. */ 443 extern short *deprecated_value_regnum_hack (struct value *); 444 #define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val)) 445 446 /* Return value after lval_funcs->coerce_ref (after check_typedef). Return 447 NULL if lval_funcs->coerce_ref is not applicable for whatever reason. */ 448 449 extern struct value *coerce_ref_if_computed (const struct value *arg); 450 451 /* Setup a new value type and enclosing value type for dereferenced value VALUE. 452 ENC_TYPE is the new enclosing type that should be set. ORIGINAL_TYPE and 453 ORIGINAL_VAL are the type and value of the original reference or pointer. 454 455 Note, that VALUE is modified by this function. 456 457 It is a common implementation for coerce_ref and value_ind. */ 458 459 extern struct value * readjust_indirect_value_type (struct value *value, 460 struct type *enc_type, 461 const struct type *original_type, 462 const struct value *original_val); 463 464 /* Convert a REF to the object referenced. */ 465 466 extern struct value *coerce_ref (struct value *value); 467 468 /* If ARG is an array, convert it to a pointer. 469 If ARG is a function, convert it to a function pointer. 470 471 References are dereferenced. */ 472 473 extern struct value *coerce_array (struct value *value); 474 475 /* Given a value, determine whether the bits starting at OFFSET and 476 extending for LENGTH bits are a synthetic pointer. */ 477 478 extern int value_bits_synthetic_pointer (const struct value *value, 479 LONGEST offset, LONGEST length); 480 481 /* Given a value, determine whether the contents bytes starting at 482 OFFSET and extending for LENGTH bytes are available. This returns 483 nonzero if all bytes in the given range are available, zero if any 484 byte is unavailable. */ 485 486 extern int value_bytes_available (const struct value *value, 487 LONGEST offset, LONGEST length); 488 489 /* Given a value, determine whether the contents bits starting at 490 OFFSET and extending for LENGTH bits are available. This returns 491 nonzero if all bits in the given range are available, zero if any 492 bit is unavailable. */ 493 494 extern int value_bits_available (const struct value *value, 495 LONGEST offset, LONGEST length); 496 497 /* Like value_bytes_available, but return false if any byte in the 498 whole object is unavailable. */ 499 extern int value_entirely_available (struct value *value); 500 501 /* Like value_entirely_available, but return false if any byte in the 502 whole object is available. */ 503 extern int value_entirely_unavailable (struct value *value); 504 505 /* Mark VALUE's content bytes starting at OFFSET and extending for 506 LENGTH bytes as unavailable. */ 507 508 extern void mark_value_bytes_unavailable (struct value *value, 509 LONGEST offset, LONGEST length); 510 511 /* Mark VALUE's content bits starting at OFFSET and extending for 512 LENGTH bits as unavailable. */ 513 514 extern void mark_value_bits_unavailable (struct value *value, 515 LONGEST offset, LONGEST length); 516 517 /* Compare LENGTH bytes of VAL1's contents starting at OFFSET1 with 518 LENGTH bytes of VAL2's contents starting at OFFSET2. 519 520 Note that "contents" refers to the whole value's contents 521 (value_contents_all), without any embedded offset adjustment. For 522 example, to compare a complete object value with itself, including 523 its enclosing type chunk, you'd do: 524 525 int len = TYPE_LENGTH (check_typedef (value_enclosing_type (val))); 526 value_contents_eq (val, 0, val, 0, len); 527 528 Returns true iff the set of available/valid contents match. 529 530 Optimized-out contents are equal to optimized-out contents, and are 531 not equal to non-optimized-out contents. 532 533 Unavailable contente are equal to unavailable contents, and are not 534 equal to non-unavailable contents. 535 536 For example, if 'x's represent an unavailable byte, and 'V' and 'Z' 537 represent different available/valid bytes, in a value with length 538 16: 539 540 offset: 0 4 8 12 16 541 contents: xxxxVVVVxxxxVVZZ 542 543 then: 544 545 value_contents_eq(val, 0, val, 8, 6) => 1 546 value_contents_eq(val, 0, val, 4, 4) => 0 547 value_contents_eq(val, 0, val, 8, 8) => 0 548 value_contents_eq(val, 4, val, 12, 2) => 1 549 value_contents_eq(val, 4, val, 12, 4) => 0 550 value_contents_eq(val, 3, val, 4, 4) => 0 551 552 If 'x's represent an unavailable byte, 'o' represents an optimized 553 out byte, in a value with length 8: 554 555 offset: 0 4 8 556 contents: xxxxoooo 557 558 then: 559 560 value_contents_eq(val, 0, val, 2, 2) => 1 561 value_contents_eq(val, 4, val, 6, 2) => 1 562 value_contents_eq(val, 0, val, 4, 4) => 0 563 564 We only know whether a value chunk is unavailable or optimized out 565 if we've tried to read it. As this routine is used by printing 566 routines, which may be printing values in the value history, long 567 after the inferior is gone, it works with const values. Therefore, 568 this routine must not be called with lazy values. */ 569 570 extern int value_contents_eq (const struct value *val1, LONGEST offset1, 571 const struct value *val2, LONGEST offset2, 572 LONGEST length); 573 574 /* Read LENGTH addressable memory units starting at MEMADDR into BUFFER, 575 which is (or will be copied to) VAL's contents buffer offset by 576 EMBEDDED_OFFSET (that is, to &VAL->contents[EMBEDDED_OFFSET]). 577 Marks value contents ranges as unavailable if the corresponding 578 memory is likewise unavailable. STACK indicates whether the memory 579 is known to be stack memory. */ 580 581 extern void read_value_memory (struct value *val, LONGEST embedded_offset, 582 int stack, CORE_ADDR memaddr, 583 gdb_byte *buffer, size_t length); 584 585 /* Cast SCALAR_VALUE to the element type of VECTOR_TYPE, then replicate 586 into each element of a new vector value with VECTOR_TYPE. */ 587 588 struct value *value_vector_widen (struct value *scalar_value, 589 struct type *vector_type); 590 591 592 594 #include "symtab.h" 595 #include "gdbtypes.h" 596 #include "expression.h" 597 598 struct frame_info; 599 struct fn_field; 600 601 extern int print_address_demangle (const struct value_print_options *, 602 struct gdbarch *, CORE_ADDR, 603 struct ui_file *, int); 604 605 extern LONGEST value_as_long (struct value *val); 606 extern DOUBLEST value_as_double (struct value *val); 607 extern CORE_ADDR value_as_address (struct value *val); 608 609 extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr); 610 extern DOUBLEST unpack_double (struct type *type, const gdb_byte *valaddr, 611 int *invp); 612 extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr); 613 614 extern LONGEST unpack_field_as_long (struct type *type, 615 const gdb_byte *valaddr, 616 int fieldno); 617 extern int unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr, 618 LONGEST embedded_offset, int fieldno, 619 const struct value *val, LONGEST *result); 620 621 extern void unpack_value_bitfield (struct value *dest_val, 622 LONGEST bitpos, LONGEST bitsize, 623 const gdb_byte *valaddr, 624 LONGEST embedded_offset, 625 const struct value *val); 626 627 extern struct value *value_field_bitfield (struct type *type, int fieldno, 628 const gdb_byte *valaddr, 629 LONGEST embedded_offset, 630 const struct value *val); 631 632 extern void pack_long (gdb_byte *buf, struct type *type, LONGEST num); 633 634 extern struct value *value_from_longest (struct type *type, LONGEST num); 635 extern struct value *value_from_ulongest (struct type *type, ULONGEST num); 636 extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr); 637 extern struct value *value_from_double (struct type *type, DOUBLEST num); 638 extern struct value *value_from_decfloat (struct type *type, 639 const gdb_byte *decbytes); 640 extern struct value *value_from_history_ref (const char *, const char **); 641 642 extern struct value *value_at (struct type *type, CORE_ADDR addr); 643 extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr); 644 645 extern struct value *value_from_contents_and_address_unresolved 646 (struct type *, const gdb_byte *, CORE_ADDR); 647 extern struct value *value_from_contents_and_address (struct type *, 648 const gdb_byte *, 649 CORE_ADDR); 650 extern struct value *value_from_contents (struct type *, const gdb_byte *); 651 652 extern struct value *default_value_from_register (struct gdbarch *gdbarch, 653 struct type *type, 654 int regnum, 655 struct frame_id frame_id); 656 657 extern void read_frame_register_value (struct value *value, 658 struct frame_info *frame); 659 660 extern struct value *value_from_register (struct type *type, int regnum, 661 struct frame_info *frame); 662 663 extern CORE_ADDR address_from_register (int regnum, 664 struct frame_info *frame); 665 666 extern struct value *value_of_variable (struct symbol *var, 667 const struct block *b); 668 669 extern struct value *address_of_variable (struct symbol *var, 670 const struct block *b); 671 672 extern struct value *value_of_register (int regnum, struct frame_info *frame); 673 674 struct value *value_of_register_lazy (struct frame_info *frame, int regnum); 675 676 /* Return the symbol's reading requirement. */ 677 678 extern enum symbol_needs_kind symbol_read_needs (struct symbol *); 679 680 /* Return true if the symbol needs a frame. This is a wrapper for 681 symbol_read_needs that simply checks for SYMBOL_NEEDS_FRAME. */ 682 683 extern int symbol_read_needs_frame (struct symbol *); 684 685 extern struct value *read_var_value (struct symbol *var, 686 const struct block *var_block, 687 struct frame_info *frame); 688 689 extern struct value *default_read_var_value (struct symbol *var, 690 const struct block *var_block, 691 struct frame_info *frame); 692 693 extern struct value *allocate_value (struct type *type); 694 extern struct value *allocate_value_lazy (struct type *type); 695 extern void value_contents_copy (struct value *dst, LONGEST dst_offset, 696 struct value *src, LONGEST src_offset, 697 LONGEST length); 698 extern void value_contents_copy_raw (struct value *dst, LONGEST dst_offset, 699 struct value *src, LONGEST src_offset, 700 LONGEST length); 701 702 extern struct value *allocate_repeat_value (struct type *type, int count); 703 704 extern struct value *value_mark (void); 705 706 extern void value_free_to_mark (const struct value *mark); 707 708 extern struct value *value_cstring (const char *ptr, ssize_t len, 709 struct type *char_type); 710 extern struct value *value_string (const char *ptr, ssize_t len, 711 struct type *char_type); 712 713 extern struct value *value_array (int lowbound, int highbound, 714 struct value **elemvec); 715 716 extern struct value *value_concat (struct value *arg1, struct value *arg2); 717 718 extern struct value *value_binop (struct value *arg1, struct value *arg2, 719 enum exp_opcode op); 720 721 extern struct value *value_ptradd (struct value *arg1, LONGEST arg2); 722 723 extern LONGEST value_ptrdiff (struct value *arg1, struct value *arg2); 724 725 extern int value_must_coerce_to_target (struct value *arg1); 726 727 extern struct value *value_coerce_to_target (struct value *arg1); 728 729 extern struct value *value_coerce_array (struct value *arg1); 730 731 extern struct value *value_coerce_function (struct value *arg1); 732 733 extern struct value *value_ind (struct value *arg1); 734 735 extern struct value *value_addr (struct value *arg1); 736 737 extern struct value *value_ref (struct value *arg1); 738 739 extern struct value *value_assign (struct value *toval, 740 struct value *fromval); 741 742 extern struct value *value_pos (struct value *arg1); 743 744 extern struct value *value_neg (struct value *arg1); 745 746 extern struct value *value_complement (struct value *arg1); 747 748 extern struct value *value_struct_elt (struct value **argp, 749 struct value **args, 750 const char *name, int *static_memfuncp, 751 const char *err); 752 753 extern struct value *value_struct_elt_bitpos (struct value **argp, 754 int bitpos, 755 struct type *field_type, 756 const char *err); 757 758 extern struct value *value_aggregate_elt (struct type *curtype, 759 const char *name, 760 struct type *expect_type, 761 int want_address, 762 enum noside noside); 763 764 extern struct value *value_static_field (struct type *type, int fieldno); 765 766 enum oload_search_type { NON_METHOD, METHOD, BOTH }; 767 768 extern int find_overload_match (struct value **args, int nargs, 769 const char *name, 770 enum oload_search_type method, 771 struct value **objp, struct symbol *fsym, 772 struct value **valp, struct symbol **symp, 773 int *staticp, const int no_adl, 774 enum noside noside); 775 776 extern struct value *value_field (struct value *arg1, int fieldno); 777 778 extern struct value *value_primitive_field (struct value *arg1, LONGEST offset, 779 int fieldno, 780 struct type *arg_type); 781 782 783 extern struct type *value_rtti_indirect_type (struct value *, int *, LONGEST *, 784 int *); 785 786 extern struct value *value_full_object (struct value *, struct type *, int, 787 int, int); 788 789 extern struct value *value_cast_pointers (struct type *, struct value *, int); 790 791 extern struct value *value_cast (struct type *type, struct value *arg2); 792 793 extern struct value *value_reinterpret_cast (struct type *type, 794 struct value *arg); 795 796 extern struct value *value_dynamic_cast (struct type *type, struct value *arg); 797 798 extern struct value *value_zero (struct type *type, enum lval_type lv); 799 800 extern struct value *value_one (struct type *type); 801 802 extern struct value *value_repeat (struct value *arg1, int count); 803 804 extern struct value *value_subscript (struct value *array, LONGEST index); 805 806 extern struct value *value_bitstring_subscript (struct type *type, 807 struct value *bitstring, 808 LONGEST index); 809 810 extern struct value *register_value_being_returned (struct type *valtype, 811 struct regcache *retbuf); 812 813 extern int value_in (struct value *element, struct value *set); 814 815 extern int value_bit_index (struct type *type, const gdb_byte *addr, 816 int index); 817 818 extern enum return_value_convention 819 struct_return_convention (struct gdbarch *gdbarch, struct value *function, 820 struct type *value_type); 821 822 extern int using_struct_return (struct gdbarch *gdbarch, 823 struct value *function, 824 struct type *value_type); 825 826 extern struct value *evaluate_expression (struct expression *exp); 827 828 extern struct value *evaluate_type (struct expression *exp); 829 830 extern struct value *evaluate_subexp (struct type *expect_type, 831 struct expression *exp, 832 int *pos, enum noside noside); 833 834 extern struct value *evaluate_subexpression_type (struct expression *exp, 835 int subexp); 836 837 extern void fetch_subexp_value (struct expression *exp, int *pc, 838 struct value **valp, struct value **resultp, 839 struct value **val_chain, 840 int preserve_errors); 841 842 extern char *extract_field_op (struct expression *exp, int *subexp); 843 844 extern struct value *evaluate_subexp_with_coercion (struct expression *, 845 int *, enum noside); 846 847 extern struct value *parse_and_eval (const char *exp); 848 849 extern struct value *parse_to_comma_and_eval (const char **expp); 850 851 extern struct type *parse_and_eval_type (char *p, int length); 852 853 extern CORE_ADDR parse_and_eval_address (const char *exp); 854 855 extern LONGEST parse_and_eval_long (const char *exp); 856 857 extern void unop_promote (const struct language_defn *language, 858 struct gdbarch *gdbarch, 859 struct value **arg1); 860 861 extern void binop_promote (const struct language_defn *language, 862 struct gdbarch *gdbarch, 863 struct value **arg1, struct value **arg2); 864 865 extern struct value *access_value_history (int num); 866 867 extern struct value *value_of_internalvar (struct gdbarch *gdbarch, 868 struct internalvar *var); 869 870 extern int get_internalvar_integer (struct internalvar *var, LONGEST *l); 871 872 extern void set_internalvar (struct internalvar *var, struct value *val); 873 874 extern void set_internalvar_integer (struct internalvar *var, LONGEST l); 875 876 extern void set_internalvar_string (struct internalvar *var, 877 const char *string); 878 879 extern void clear_internalvar (struct internalvar *var); 880 881 extern void set_internalvar_component (struct internalvar *var, 882 LONGEST offset, 883 LONGEST bitpos, LONGEST bitsize, 884 struct value *newvalue); 885 886 extern struct internalvar *lookup_only_internalvar (const char *name); 887 888 extern struct internalvar *create_internalvar (const char *name); 889 890 extern VEC (char_ptr) *complete_internalvar (const char *name); 891 892 /* An internalvar can be dynamically computed by supplying a vector of 893 function pointers to perform various operations. */ 894 895 struct internalvar_funcs 896 { 897 /* Compute the value of the variable. The DATA argument passed to 898 the function is the same argument that was passed to 899 `create_internalvar_type_lazy'. */ 900 901 struct value *(*make_value) (struct gdbarch *arch, 902 struct internalvar *var, 903 void *data); 904 905 /* Update the agent expression EXPR with bytecode to compute the 906 value. VALUE is the agent value we are updating. The DATA 907 argument passed to this function is the same argument that was 908 passed to `create_internalvar_type_lazy'. If this pointer is 909 NULL, then the internalvar cannot be compiled to an agent 910 expression. */ 911 912 void (*compile_to_ax) (struct internalvar *var, 913 struct agent_expr *expr, 914 struct axs_value *value, 915 void *data); 916 917 /* If non-NULL, this is called to destroy DATA. The DATA argument 918 passed to this function is the same argument that was passed to 919 `create_internalvar_type_lazy'. */ 920 921 void (*destroy) (void *data); 922 }; 923 924 extern struct internalvar *create_internalvar_type_lazy (const char *name, 925 const struct internalvar_funcs *funcs, 926 void *data); 927 928 /* Compile an internal variable to an agent expression. VAR is the 929 variable to compile; EXPR and VALUE are the agent expression we are 930 updating. This will return 0 if there is no known way to compile 931 VAR, and 1 if VAR was successfully compiled. It may also throw an 932 exception on error. */ 933 934 extern int compile_internalvar_to_ax (struct internalvar *var, 935 struct agent_expr *expr, 936 struct axs_value *value); 937 938 extern struct internalvar *lookup_internalvar (const char *name); 939 940 extern int value_equal (struct value *arg1, struct value *arg2); 941 942 extern int value_equal_contents (struct value *arg1, struct value *arg2); 943 944 extern int value_less (struct value *arg1, struct value *arg2); 945 946 extern int value_logical_not (struct value *arg1); 947 948 /* C++ */ 949 950 extern struct value *value_of_this (const struct language_defn *lang); 951 952 extern struct value *value_of_this_silent (const struct language_defn *lang); 953 954 extern struct value *value_x_binop (struct value *arg1, struct value *arg2, 955 enum exp_opcode op, 956 enum exp_opcode otherop, 957 enum noside noside); 958 959 extern struct value *value_x_unop (struct value *arg1, enum exp_opcode op, 960 enum noside noside); 961 962 extern struct value *value_fn_field (struct value **arg1p, struct fn_field *f, 963 int j, struct type *type, LONGEST offset); 964 965 extern int binop_types_user_defined_p (enum exp_opcode op, 966 struct type *type1, 967 struct type *type2); 968 969 extern int binop_user_defined_p (enum exp_opcode op, struct value *arg1, 970 struct value *arg2); 971 972 extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1); 973 974 extern int destructor_name_p (const char *name, struct type *type); 975 976 extern void value_incref (struct value *val); 977 978 extern void value_free (struct value *val); 979 980 extern void free_all_values (void); 981 982 extern void free_value_chain (struct value *v); 983 984 extern void release_value (struct value *val); 985 986 extern void release_value_or_incref (struct value *val); 987 988 extern int record_latest_value (struct value *val); 989 990 extern void modify_field (struct type *type, gdb_byte *addr, 991 LONGEST fieldval, LONGEST bitpos, LONGEST bitsize); 992 993 extern void type_print (struct type *type, const char *varstring, 994 struct ui_file *stream, int show); 995 996 extern char *type_to_string (struct type *type); 997 998 extern gdb_byte *baseclass_addr (struct type *type, int index, 999 gdb_byte *valaddr, 1000 struct value **valuep, int *errp); 1001 1002 extern void print_longest (struct ui_file *stream, int format, 1003 int use_local, LONGEST val); 1004 1005 extern void print_floating (const gdb_byte *valaddr, struct type *type, 1006 struct ui_file *stream); 1007 1008 extern void print_decimal_floating (const gdb_byte *valaddr, struct type *type, 1009 struct ui_file *stream); 1010 1011 extern void value_print (struct value *val, struct ui_file *stream, 1012 const struct value_print_options *options); 1013 1014 extern void value_print_array_elements (struct value *val, 1015 struct ui_file *stream, int format, 1016 enum val_prettyformat pretty); 1017 1018 extern struct value *value_release_to_mark (const struct value *mark); 1019 1020 extern void val_print (struct type *type, const gdb_byte *valaddr, 1021 LONGEST embedded_offset, CORE_ADDR address, 1022 struct ui_file *stream, int recurse, 1023 const struct value *val, 1024 const struct value_print_options *options, 1025 const struct language_defn *language); 1026 1027 extern void common_val_print (struct value *val, 1028 struct ui_file *stream, int recurse, 1029 const struct value_print_options *options, 1030 const struct language_defn *language); 1031 1032 extern int val_print_string (struct type *elttype, const char *encoding, 1033 CORE_ADDR addr, int len, 1034 struct ui_file *stream, 1035 const struct value_print_options *options); 1036 1037 extern void print_variable_and_value (const char *name, 1038 struct symbol *var, 1039 struct frame_info *frame, 1040 struct ui_file *stream, 1041 int indent); 1042 1043 extern void typedef_print (struct type *type, struct symbol *news, 1044 struct ui_file *stream); 1045 1046 extern char *internalvar_name (const struct internalvar *var); 1047 1048 extern void preserve_values (struct objfile *); 1049 1050 /* From values.c */ 1051 1052 extern struct value *value_copy (struct value *); 1053 1054 extern struct value *value_non_lval (struct value *); 1055 1056 extern void value_force_lval (struct value *, CORE_ADDR); 1057 1058 extern struct value *make_cv_value (int, int, struct value *); 1059 1060 extern void preserve_one_value (struct value *, struct objfile *, htab_t); 1061 1062 /* From valops.c */ 1063 1064 extern struct value *varying_to_slice (struct value *); 1065 1066 extern struct value *value_slice (struct value *, int, int); 1067 1068 extern struct value *value_literal_complex (struct value *, struct value *, 1069 struct type *); 1070 1071 extern struct value *find_function_in_inferior (const char *, 1072 struct objfile **); 1073 1074 extern struct value *value_allocate_space_in_inferior (int); 1075 1076 extern struct value *value_subscripted_rvalue (struct value *array, 1077 LONGEST index, int lowerbound); 1078 1079 /* User function handler. */ 1080 1081 typedef struct value *(*internal_function_fn) (struct gdbarch *gdbarch, 1082 const struct language_defn *language, 1083 void *cookie, 1084 int argc, 1085 struct value **argv); 1086 1087 void add_internal_function (const char *name, const char *doc, 1088 internal_function_fn handler, 1089 void *cookie); 1090 1091 struct value *call_internal_function (struct gdbarch *gdbarch, 1092 const struct language_defn *language, 1093 struct value *function, 1094 int argc, struct value **argv); 1095 1096 char *value_internal_function_name (struct value *); 1097 1098 extern struct value *value_of_xmethod (struct xmethod_worker *); 1099 1100 extern struct type *result_type_of_xmethod (struct value *method, 1101 int argc, struct value **argv); 1102 1103 extern struct value *call_xmethod (struct value *method, 1104 int argc, struct value **argv); 1105 1106 #endif /* !defined (VALUE_H) */ 1107
Indexes created Sun Mar 01 05:31:48 UTC 2026