value.h revision 1.6.4.1
1 /* Definitions for values of C expressions, for GDB. 2 3 Copyright (C) 1986-2017 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 ID of "next" frame to which a register value is relative. A 438 register value is indicated by VALUE_LVAL being set to lval_register. 439 So, if the register value is found relative to frame F, then the 440 frame id of F->next will be stored in VALUE_NEXT_FRAME_ID. */ 441 extern struct frame_id *deprecated_value_next_frame_id_hack (struct value *); 442 #define VALUE_NEXT_FRAME_ID(val) (*deprecated_value_next_frame_id_hack (val)) 443 444 /* Frame ID of frame to which a register value is relative. This is 445 similar to VALUE_NEXT_FRAME_ID, above, but may not be assigned to. 446 Note that VALUE_FRAME_ID effectively undoes the "next" operation 447 that was performed during the assignment to VALUE_NEXT_FRAME_ID. */ 448 #define VALUE_FRAME_ID(val) (get_prev_frame_id_by_id (VALUE_NEXT_FRAME_ID (val))) 449 450 /* Register number if the value is from a register. */ 451 extern int *deprecated_value_regnum_hack (struct value *); 452 #define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val)) 453 454 /* Return value after lval_funcs->coerce_ref (after check_typedef). Return 455 NULL if lval_funcs->coerce_ref is not applicable for whatever reason. */ 456 457 extern struct value *coerce_ref_if_computed (const struct value *arg); 458 459 /* Setup a new value type and enclosing value type for dereferenced value VALUE. 460 ENC_TYPE is the new enclosing type that should be set. ORIGINAL_TYPE and 461 ORIGINAL_VAL are the type and value of the original reference or pointer. 462 463 Note, that VALUE is modified by this function. 464 465 It is a common implementation for coerce_ref and value_ind. */ 466 467 extern struct value * readjust_indirect_value_type (struct value *value, 468 struct type *enc_type, 469 const struct type *original_type, 470 const struct value *original_val); 471 472 /* Convert a REF to the object referenced. */ 473 474 extern struct value *coerce_ref (struct value *value); 475 476 /* If ARG is an array, convert it to a pointer. 477 If ARG is a function, convert it to a function pointer. 478 479 References are dereferenced. */ 480 481 extern struct value *coerce_array (struct value *value); 482 483 /* Given a value, determine whether the bits starting at OFFSET and 484 extending for LENGTH bits are a synthetic pointer. */ 485 486 extern int value_bits_synthetic_pointer (const struct value *value, 487 LONGEST offset, LONGEST length); 488 489 /* Given a value, determine whether the contents bytes starting at 490 OFFSET and extending for LENGTH bytes are available. This returns 491 nonzero if all bytes in the given range are available, zero if any 492 byte is unavailable. */ 493 494 extern int value_bytes_available (const struct value *value, 495 LONGEST offset, LONGEST length); 496 497 /* Given a value, determine whether the contents bits starting at 498 OFFSET and extending for LENGTH bits are available. This returns 499 nonzero if all bits in the given range are available, zero if any 500 bit is unavailable. */ 501 502 extern int value_bits_available (const struct value *value, 503 LONGEST offset, LONGEST length); 504 505 /* Like value_bytes_available, but return false if any byte in the 506 whole object is unavailable. */ 507 extern int value_entirely_available (struct value *value); 508 509 /* Like value_entirely_available, but return false if any byte in the 510 whole object is available. */ 511 extern int value_entirely_unavailable (struct value *value); 512 513 /* Mark VALUE's content bytes starting at OFFSET and extending for 514 LENGTH bytes as unavailable. */ 515 516 extern void mark_value_bytes_unavailable (struct value *value, 517 LONGEST offset, LONGEST length); 518 519 /* Mark VALUE's content bits starting at OFFSET and extending for 520 LENGTH bits as unavailable. */ 521 522 extern void mark_value_bits_unavailable (struct value *value, 523 LONGEST offset, LONGEST length); 524 525 /* Compare LENGTH bytes of VAL1's contents starting at OFFSET1 with 526 LENGTH bytes of VAL2's contents starting at OFFSET2. 527 528 Note that "contents" refers to the whole value's contents 529 (value_contents_all), without any embedded offset adjustment. For 530 example, to compare a complete object value with itself, including 531 its enclosing type chunk, you'd do: 532 533 int len = TYPE_LENGTH (check_typedef (value_enclosing_type (val))); 534 value_contents_eq (val, 0, val, 0, len); 535 536 Returns true iff the set of available/valid contents match. 537 538 Optimized-out contents are equal to optimized-out contents, and are 539 not equal to non-optimized-out contents. 540 541 Unavailable contente are equal to unavailable contents, and are not 542 equal to non-unavailable contents. 543 544 For example, if 'x's represent an unavailable byte, and 'V' and 'Z' 545 represent different available/valid bytes, in a value with length 546 16: 547 548 offset: 0 4 8 12 16 549 contents: xxxxVVVVxxxxVVZZ 550 551 then: 552 553 value_contents_eq(val, 0, val, 8, 6) => 1 554 value_contents_eq(val, 0, val, 4, 4) => 0 555 value_contents_eq(val, 0, val, 8, 8) => 0 556 value_contents_eq(val, 4, val, 12, 2) => 1 557 value_contents_eq(val, 4, val, 12, 4) => 0 558 value_contents_eq(val, 3, val, 4, 4) => 0 559 560 If 'x's represent an unavailable byte, 'o' represents an optimized 561 out byte, in a value with length 8: 562 563 offset: 0 4 8 564 contents: xxxxoooo 565 566 then: 567 568 value_contents_eq(val, 0, val, 2, 2) => 1 569 value_contents_eq(val, 4, val, 6, 2) => 1 570 value_contents_eq(val, 0, val, 4, 4) => 0 571 572 We only know whether a value chunk is unavailable or optimized out 573 if we've tried to read it. As this routine is used by printing 574 routines, which may be printing values in the value history, long 575 after the inferior is gone, it works with const values. Therefore, 576 this routine must not be called with lazy values. */ 577 578 extern int value_contents_eq (const struct value *val1, LONGEST offset1, 579 const struct value *val2, LONGEST offset2, 580 LONGEST length); 581 582 /* Read LENGTH addressable memory units starting at MEMADDR into BUFFER, 583 which is (or will be copied to) VAL's contents buffer offset by 584 EMBEDDED_OFFSET (that is, to &VAL->contents[EMBEDDED_OFFSET]). 585 Marks value contents ranges as unavailable if the corresponding 586 memory is likewise unavailable. STACK indicates whether the memory 587 is known to be stack memory. */ 588 589 extern void read_value_memory (struct value *val, LONGEST embedded_offset, 590 int stack, CORE_ADDR memaddr, 591 gdb_byte *buffer, size_t length); 592 593 /* Cast SCALAR_VALUE to the element type of VECTOR_TYPE, then replicate 594 into each element of a new vector value with VECTOR_TYPE. */ 595 596 struct value *value_vector_widen (struct value *scalar_value, 597 struct type *vector_type); 598 599 600 602 #include "symtab.h" 603 #include "gdbtypes.h" 604 #include "expression.h" 605 606 struct frame_info; 607 struct fn_field; 608 609 extern int print_address_demangle (const struct value_print_options *, 610 struct gdbarch *, CORE_ADDR, 611 struct ui_file *, int); 612 613 extern LONGEST value_as_long (struct value *val); 614 extern DOUBLEST value_as_double (struct value *val); 615 extern CORE_ADDR value_as_address (struct value *val); 616 617 extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr); 618 extern DOUBLEST unpack_double (struct type *type, const gdb_byte *valaddr, 619 int *invp); 620 extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr); 621 622 extern LONGEST unpack_field_as_long (struct type *type, 623 const gdb_byte *valaddr, 624 int fieldno); 625 extern int unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr, 626 LONGEST embedded_offset, int fieldno, 627 const struct value *val, LONGEST *result); 628 629 extern void unpack_value_bitfield (struct value *dest_val, 630 LONGEST bitpos, LONGEST bitsize, 631 const gdb_byte *valaddr, 632 LONGEST embedded_offset, 633 const struct value *val); 634 635 extern struct value *value_field_bitfield (struct type *type, int fieldno, 636 const gdb_byte *valaddr, 637 LONGEST embedded_offset, 638 const struct value *val); 639 640 extern void pack_long (gdb_byte *buf, struct type *type, LONGEST num); 641 642 extern struct value *value_from_longest (struct type *type, LONGEST num); 643 extern struct value *value_from_ulongest (struct type *type, ULONGEST num); 644 extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr); 645 extern struct value *value_from_double (struct type *type, DOUBLEST num); 646 extern struct value *value_from_decfloat (struct type *type, 647 const gdb_byte *decbytes); 648 extern struct value *value_from_history_ref (const char *, const char **); 649 extern struct value *value_from_component (struct value *, struct type *, 650 LONGEST); 651 652 extern struct value *value_at (struct type *type, CORE_ADDR addr); 653 extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr); 654 655 extern struct value *value_from_contents_and_address_unresolved 656 (struct type *, const gdb_byte *, CORE_ADDR); 657 extern struct value *value_from_contents_and_address (struct type *, 658 const gdb_byte *, 659 CORE_ADDR); 660 extern struct value *value_from_contents (struct type *, const gdb_byte *); 661 662 extern struct value *default_value_from_register (struct gdbarch *gdbarch, 663 struct type *type, 664 int regnum, 665 struct frame_id frame_id); 666 667 extern void read_frame_register_value (struct value *value, 668 struct frame_info *frame); 669 670 extern struct value *value_from_register (struct type *type, int regnum, 671 struct frame_info *frame); 672 673 extern CORE_ADDR address_from_register (int regnum, 674 struct frame_info *frame); 675 676 extern struct value *value_of_variable (struct symbol *var, 677 const struct block *b); 678 679 extern struct value *address_of_variable (struct symbol *var, 680 const struct block *b); 681 682 extern struct value *value_of_register (int regnum, struct frame_info *frame); 683 684 struct value *value_of_register_lazy (struct frame_info *frame, int regnum); 685 686 /* Return the symbol's reading requirement. */ 687 688 extern enum symbol_needs_kind symbol_read_needs (struct symbol *); 689 690 /* Return true if the symbol needs a frame. This is a wrapper for 691 symbol_read_needs that simply checks for SYMBOL_NEEDS_FRAME. */ 692 693 extern int symbol_read_needs_frame (struct symbol *); 694 695 extern struct value *read_var_value (struct symbol *var, 696 const struct block *var_block, 697 struct frame_info *frame); 698 699 extern struct value *default_read_var_value (struct symbol *var, 700 const struct block *var_block, 701 struct frame_info *frame); 702 703 extern struct value *allocate_value (struct type *type); 704 extern struct value *allocate_value_lazy (struct type *type); 705 extern void value_contents_copy (struct value *dst, LONGEST dst_offset, 706 struct value *src, LONGEST src_offset, 707 LONGEST length); 708 extern void value_contents_copy_raw (struct value *dst, LONGEST dst_offset, 709 struct value *src, LONGEST src_offset, 710 LONGEST length); 711 712 extern struct value *allocate_repeat_value (struct type *type, int count); 713 714 extern struct value *value_mark (void); 715 716 extern void value_free_to_mark (const struct value *mark); 717 718 /* A helper class that uses value_mark at construction time and calls 719 value_free_to_mark in the destructor. This is used to clear out 720 temporary values created during the lifetime of this object. */ 721 class scoped_value_mark 722 { 723 public: 724 725 scoped_value_mark () 726 : m_value (value_mark ()) 727 { 728 } 729 730 ~scoped_value_mark () 731 { 732 free_to_mark (); 733 } 734 735 /* Free the values currently on the value stack. */ 736 void free_to_mark () 737 { 738 if (m_value != NULL) 739 { 740 value_free_to_mark (m_value); 741 m_value = NULL; 742 } 743 } 744 745 private: 746 747 const struct value *m_value; 748 }; 749 750 extern struct value *value_cstring (const char *ptr, ssize_t len, 751 struct type *char_type); 752 extern struct value *value_string (const char *ptr, ssize_t len, 753 struct type *char_type); 754 755 extern struct value *value_array (int lowbound, int highbound, 756 struct value **elemvec); 757 758 extern struct value *value_concat (struct value *arg1, struct value *arg2); 759 760 extern struct value *value_binop (struct value *arg1, struct value *arg2, 761 enum exp_opcode op); 762 763 extern struct value *value_ptradd (struct value *arg1, LONGEST arg2); 764 765 extern LONGEST value_ptrdiff (struct value *arg1, struct value *arg2); 766 767 extern int value_must_coerce_to_target (struct value *arg1); 768 769 extern struct value *value_coerce_to_target (struct value *arg1); 770 771 extern struct value *value_coerce_array (struct value *arg1); 772 773 extern struct value *value_coerce_function (struct value *arg1); 774 775 extern struct value *value_ind (struct value *arg1); 776 777 extern struct value *value_addr (struct value *arg1); 778 779 extern struct value *value_ref (struct value *arg1, enum type_code refcode); 780 781 extern struct value *value_assign (struct value *toval, 782 struct value *fromval); 783 784 extern struct value *value_pos (struct value *arg1); 785 786 extern struct value *value_neg (struct value *arg1); 787 788 extern struct value *value_complement (struct value *arg1); 789 790 extern struct value *value_struct_elt (struct value **argp, 791 struct value **args, 792 const char *name, int *static_memfuncp, 793 const char *err); 794 795 extern struct value *value_struct_elt_bitpos (struct value **argp, 796 int bitpos, 797 struct type *field_type, 798 const char *err); 799 800 extern struct value *value_aggregate_elt (struct type *curtype, 801 const char *name, 802 struct type *expect_type, 803 int want_address, 804 enum noside noside); 805 806 extern struct value *value_static_field (struct type *type, int fieldno); 807 808 enum oload_search_type { NON_METHOD, METHOD, BOTH }; 809 810 extern int find_overload_match (struct value **args, int nargs, 811 const char *name, 812 enum oload_search_type method, 813 struct value **objp, struct symbol *fsym, 814 struct value **valp, struct symbol **symp, 815 int *staticp, const int no_adl, 816 enum noside noside); 817 818 extern struct value *value_field (struct value *arg1, int fieldno); 819 820 extern struct value *value_primitive_field (struct value *arg1, LONGEST offset, 821 int fieldno, 822 struct type *arg_type); 823 824 825 extern struct type *value_rtti_indirect_type (struct value *, int *, LONGEST *, 826 int *); 827 828 extern struct value *value_full_object (struct value *, struct type *, int, 829 int, int); 830 831 extern struct value *value_cast_pointers (struct type *, struct value *, int); 832 833 extern struct value *value_cast (struct type *type, struct value *arg2); 834 835 extern struct value *value_reinterpret_cast (struct type *type, 836 struct value *arg); 837 838 extern struct value *value_dynamic_cast (struct type *type, struct value *arg); 839 840 extern struct value *value_zero (struct type *type, enum lval_type lv); 841 842 extern struct value *value_one (struct type *type); 843 844 extern struct value *value_repeat (struct value *arg1, int count); 845 846 extern struct value *value_subscript (struct value *array, LONGEST index); 847 848 extern struct value *value_bitstring_subscript (struct type *type, 849 struct value *bitstring, 850 LONGEST index); 851 852 extern struct value *register_value_being_returned (struct type *valtype, 853 struct regcache *retbuf); 854 855 extern int value_in (struct value *element, struct value *set); 856 857 extern int value_bit_index (struct type *type, const gdb_byte *addr, 858 int index); 859 860 extern enum return_value_convention 861 struct_return_convention (struct gdbarch *gdbarch, struct value *function, 862 struct type *value_type); 863 864 extern int using_struct_return (struct gdbarch *gdbarch, 865 struct value *function, 866 struct type *value_type); 867 868 extern struct value *evaluate_expression (struct expression *exp); 869 870 extern struct value *evaluate_type (struct expression *exp); 871 872 extern struct value *evaluate_subexp (struct type *expect_type, 873 struct expression *exp, 874 int *pos, enum noside noside); 875 876 extern struct value *evaluate_subexpression_type (struct expression *exp, 877 int subexp); 878 879 extern void fetch_subexp_value (struct expression *exp, int *pc, 880 struct value **valp, struct value **resultp, 881 struct value **val_chain, 882 int preserve_errors); 883 884 extern char *extract_field_op (struct expression *exp, int *subexp); 885 886 extern struct value *evaluate_subexp_with_coercion (struct expression *, 887 int *, enum noside); 888 889 extern struct value *parse_and_eval (const char *exp); 890 891 extern struct value *parse_to_comma_and_eval (const char **expp); 892 893 extern struct type *parse_and_eval_type (char *p, int length); 894 895 extern CORE_ADDR parse_and_eval_address (const char *exp); 896 897 extern LONGEST parse_and_eval_long (const char *exp); 898 899 extern void unop_promote (const struct language_defn *language, 900 struct gdbarch *gdbarch, 901 struct value **arg1); 902 903 extern void binop_promote (const struct language_defn *language, 904 struct gdbarch *gdbarch, 905 struct value **arg1, struct value **arg2); 906 907 extern struct value *access_value_history (int num); 908 909 extern struct value *value_of_internalvar (struct gdbarch *gdbarch, 910 struct internalvar *var); 911 912 extern int get_internalvar_integer (struct internalvar *var, LONGEST *l); 913 914 extern void set_internalvar (struct internalvar *var, struct value *val); 915 916 extern void set_internalvar_integer (struct internalvar *var, LONGEST l); 917 918 extern void set_internalvar_string (struct internalvar *var, 919 const char *string); 920 921 extern void clear_internalvar (struct internalvar *var); 922 923 extern void set_internalvar_component (struct internalvar *var, 924 LONGEST offset, 925 LONGEST bitpos, LONGEST bitsize, 926 struct value *newvalue); 927 928 extern struct internalvar *lookup_only_internalvar (const char *name); 929 930 extern struct internalvar *create_internalvar (const char *name); 931 932 extern VEC (char_ptr) *complete_internalvar (const char *name); 933 934 /* An internalvar can be dynamically computed by supplying a vector of 935 function pointers to perform various operations. */ 936 937 struct internalvar_funcs 938 { 939 /* Compute the value of the variable. The DATA argument passed to 940 the function is the same argument that was passed to 941 `create_internalvar_type_lazy'. */ 942 943 struct value *(*make_value) (struct gdbarch *arch, 944 struct internalvar *var, 945 void *data); 946 947 /* Update the agent expression EXPR with bytecode to compute the 948 value. VALUE is the agent value we are updating. The DATA 949 argument passed to this function is the same argument that was 950 passed to `create_internalvar_type_lazy'. If this pointer is 951 NULL, then the internalvar cannot be compiled to an agent 952 expression. */ 953 954 void (*compile_to_ax) (struct internalvar *var, 955 struct agent_expr *expr, 956 struct axs_value *value, 957 void *data); 958 959 /* If non-NULL, this is called to destroy DATA. The DATA argument 960 passed to this function is the same argument that was passed to 961 `create_internalvar_type_lazy'. */ 962 963 void (*destroy) (void *data); 964 }; 965 966 extern struct internalvar *create_internalvar_type_lazy (const char *name, 967 const struct internalvar_funcs *funcs, 968 void *data); 969 970 /* Compile an internal variable to an agent expression. VAR is the 971 variable to compile; EXPR and VALUE are the agent expression we are 972 updating. This will return 0 if there is no known way to compile 973 VAR, and 1 if VAR was successfully compiled. It may also throw an 974 exception on error. */ 975 976 extern int compile_internalvar_to_ax (struct internalvar *var, 977 struct agent_expr *expr, 978 struct axs_value *value); 979 980 extern struct internalvar *lookup_internalvar (const char *name); 981 982 extern int value_equal (struct value *arg1, struct value *arg2); 983 984 extern int value_equal_contents (struct value *arg1, struct value *arg2); 985 986 extern int value_less (struct value *arg1, struct value *arg2); 987 988 extern int value_logical_not (struct value *arg1); 989 990 /* C++ */ 991 992 extern struct value *value_of_this (const struct language_defn *lang); 993 994 extern struct value *value_of_this_silent (const struct language_defn *lang); 995 996 extern struct value *value_x_binop (struct value *arg1, struct value *arg2, 997 enum exp_opcode op, 998 enum exp_opcode otherop, 999 enum noside noside); 1000 1001 extern struct value *value_x_unop (struct value *arg1, enum exp_opcode op, 1002 enum noside noside); 1003 1004 extern struct value *value_fn_field (struct value **arg1p, struct fn_field *f, 1005 int j, struct type *type, LONGEST offset); 1006 1007 extern int binop_types_user_defined_p (enum exp_opcode op, 1008 struct type *type1, 1009 struct type *type2); 1010 1011 extern int binop_user_defined_p (enum exp_opcode op, struct value *arg1, 1012 struct value *arg2); 1013 1014 extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1); 1015 1016 extern int destructor_name_p (const char *name, struct type *type); 1017 1018 extern void value_incref (struct value *val); 1019 1020 extern void value_free (struct value *val); 1021 1022 extern void free_all_values (void); 1023 1024 extern void free_value_chain (struct value *v); 1025 1026 extern void release_value (struct value *val); 1027 1028 extern void release_value_or_incref (struct value *val); 1029 1030 extern int record_latest_value (struct value *val); 1031 1032 extern void modify_field (struct type *type, gdb_byte *addr, 1033 LONGEST fieldval, LONGEST bitpos, LONGEST bitsize); 1034 1035 extern void type_print (struct type *type, const char *varstring, 1036 struct ui_file *stream, int show); 1037 1038 extern std::string type_to_string (struct type *type); 1039 1040 extern gdb_byte *baseclass_addr (struct type *type, int index, 1041 gdb_byte *valaddr, 1042 struct value **valuep, int *errp); 1043 1044 extern void print_longest (struct ui_file *stream, int format, 1045 int use_local, LONGEST val); 1046 1047 extern void print_floating (const gdb_byte *valaddr, struct type *type, 1048 struct ui_file *stream); 1049 1050 extern void print_decimal_floating (const gdb_byte *valaddr, struct type *type, 1051 struct ui_file *stream); 1052 1053 extern void value_print (struct value *val, struct ui_file *stream, 1054 const struct value_print_options *options); 1055 1056 extern void value_print_array_elements (struct value *val, 1057 struct ui_file *stream, int format, 1058 enum val_prettyformat pretty); 1059 1060 extern struct value *value_release_to_mark (const struct value *mark); 1061 1062 extern void val_print (struct type *type, 1063 LONGEST embedded_offset, CORE_ADDR address, 1064 struct ui_file *stream, int recurse, 1065 struct value *val, 1066 const struct value_print_options *options, 1067 const struct language_defn *language); 1068 1069 extern void common_val_print (struct value *val, 1070 struct ui_file *stream, int recurse, 1071 const struct value_print_options *options, 1072 const struct language_defn *language); 1073 1074 extern int val_print_string (struct type *elttype, const char *encoding, 1075 CORE_ADDR addr, int len, 1076 struct ui_file *stream, 1077 const struct value_print_options *options); 1078 1079 extern void print_variable_and_value (const char *name, 1080 struct symbol *var, 1081 struct frame_info *frame, 1082 struct ui_file *stream, 1083 int indent); 1084 1085 extern void typedef_print (struct type *type, struct symbol *news, 1086 struct ui_file *stream); 1087 1088 extern char *internalvar_name (const struct internalvar *var); 1089 1090 extern void preserve_values (struct objfile *); 1091 1092 /* From values.c */ 1093 1094 extern struct value *value_copy (struct value *); 1095 1096 extern struct value *value_non_lval (struct value *); 1097 1098 extern void value_force_lval (struct value *, CORE_ADDR); 1099 1100 extern struct value *make_cv_value (int, int, struct value *); 1101 1102 extern void preserve_one_value (struct value *, struct objfile *, htab_t); 1103 1104 /* From valops.c */ 1105 1106 extern struct value *varying_to_slice (struct value *); 1107 1108 extern struct value *value_slice (struct value *, int, int); 1109 1110 extern struct value *value_literal_complex (struct value *, struct value *, 1111 struct type *); 1112 1113 extern struct value *find_function_in_inferior (const char *, 1114 struct objfile **); 1115 1116 extern struct value *value_allocate_space_in_inferior (int); 1117 1118 extern struct value *value_subscripted_rvalue (struct value *array, 1119 LONGEST index, int lowerbound); 1120 1121 /* User function handler. */ 1122 1123 typedef struct value *(*internal_function_fn) (struct gdbarch *gdbarch, 1124 const struct language_defn *language, 1125 void *cookie, 1126 int argc, 1127 struct value **argv); 1128 1129 void add_internal_function (const char *name, const char *doc, 1130 internal_function_fn handler, 1131 void *cookie); 1132 1133 struct value *call_internal_function (struct gdbarch *gdbarch, 1134 const struct language_defn *language, 1135 struct value *function, 1136 int argc, struct value **argv); 1137 1138 char *value_internal_function_name (struct value *); 1139 1140 extern struct value *value_of_xmethod (struct xmethod_worker *); 1141 1142 extern struct type *result_type_of_xmethod (struct value *method, 1143 int argc, struct value **argv); 1144 1145 extern struct value *call_xmethod (struct value *method, 1146 int argc, struct value **argv); 1147 1148 #endif /* !defined (VALUE_H) */ 1149
Indexes created Sun Mar 01 05:31:48 UTC 2026