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); 590 591 592 593 #include "symtab.h" 594 #include "gdbtypes.h" 595 #include "expression.h" 596 597 struct frame_info; 598 struct fn_field; 599 600 extern int print_address_demangle (const struct value_print_options *, 601 struct gdbarch *, CORE_ADDR, 602 struct ui_file *, int); 603 604 extern LONGEST value_as_long (struct value *val); 605 extern DOUBLEST value_as_double (struct value *val); 606 extern CORE_ADDR value_as_address (struct value *val); 607 608 extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr); 609 extern DOUBLEST unpack_double (struct type *type, const gdb_byte *valaddr, 610 int *invp); 611 extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr); 612 613 extern LONGEST unpack_field_as_long (struct type *type, 614 const gdb_byte *valaddr, 615 int fieldno); 616 extern int unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr, 617 LONGEST embedded_offset, int fieldno, 618 const struct value *val, LONGEST *result); 619 620 extern void unpack_value_bitfield (struct value *dest_val, 621 LONGEST bitpos, LONGEST bitsize, 622 const gdb_byte *valaddr, 623 LONGEST embedded_offset, 624 const struct value *val); 625 626 extern struct value *value_field_bitfield (struct type *type, int fieldno, 627 const gdb_byte *valaddr, 628 LONGEST embedded_offset, 629 const struct value *val); 630 631 extern void pack_long (gdb_byte *buf, struct type *type, LONGEST num); 632 633 extern struct value *value_from_longest (struct type *type, LONGEST num); 634 extern struct value *value_from_ulongest (struct type *type, ULONGEST num); 635 extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr); 636 extern struct value *value_from_double (struct type *type, DOUBLEST num); 637 extern struct value *value_from_decfloat (struct type *type, 638 const gdb_byte *decbytes); 639 extern struct value *value_from_history_ref (const char *, const char **); 640 641 extern struct value *value_at (struct type *type, CORE_ADDR addr); 642 extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr); 643 644 extern struct value *value_from_contents_and_address_unresolved 645 (struct type *, const gdb_byte *, CORE_ADDR); 646 extern struct value *value_from_contents_and_address (struct type *, 647 const gdb_byte *, 648 CORE_ADDR); 649 extern struct value *value_from_contents (struct type *, const gdb_byte *); 650 651 extern struct value *default_value_from_register (struct gdbarch *gdbarch, 652 struct type *type, 653 int regnum, 654 struct frame_id frame_id); 655 656 extern void read_frame_register_value (struct value *value, 657 struct frame_info *frame); 658 659 extern struct value *value_from_register (struct type *type, int regnum, 660 struct frame_info *frame); 661 662 extern CORE_ADDR address_from_register (int regnum, 663 struct frame_info *frame); 664 665 extern struct value *value_of_variable (struct symbol *var, 666 const struct block *b); 667 668 extern struct value *address_of_variable (struct symbol *var, 669 const struct block *b); 670 671 extern struct value *value_of_register (int regnum, struct frame_info *frame); 672 673 struct value *value_of_register_lazy (struct frame_info *frame, int regnum); 674 675 /* Return the symbol's reading requirement. */ 676 677 extern enum symbol_needs_kind symbol_read_needs (struct symbol *); 678 679 /* Return true if the symbol needs a frame. This is a wrapper for 680 symbol_read_needs that simply checks for SYMBOL_NEEDS_FRAME. */ 681 682 extern int symbol_read_needs_frame (struct symbol *); 683 684 extern struct value *read_var_value (struct symbol *var, 685 const struct block *var_block, 686 struct frame_info *frame); 687 688 extern struct value *default_read_var_value (struct symbol *var, 689 const struct block *var_block, 690 struct frame_info *frame); 691 692 extern struct value *allocate_value (struct type *type); 693 extern struct value *allocate_value_lazy (struct type *type); 694 extern void value_contents_copy (struct value *dst, LONGEST dst_offset, 695 struct value *src, LONGEST src_offset, 696 LONGEST length); 697 extern void value_contents_copy_raw (struct value *dst, LONGEST dst_offset, 698 struct value *src, LONGEST src_offset, 699 LONGEST length); 700 701 extern struct value *allocate_repeat_value (struct type *type, int count); 702 703 extern struct value *value_mark (void); 704 705 extern void value_free_to_mark (const struct value *mark); 706 707 extern struct value *value_cstring (const char *ptr, ssize_t len, 708 struct type *char_type); 709 extern struct value *value_string (const char *ptr, ssize_t len, 710 struct type *char_type); 711 712 extern struct value *value_array (int lowbound, int highbound, 713 struct value **elemvec); 714 715 extern struct value *value_concat (struct value *arg1, struct value *arg2); 716 717 extern struct value *value_binop (struct value *arg1, struct value *arg2, 718 enum exp_opcode op); 719 720 extern struct value *value_ptradd (struct value *arg1, LONGEST arg2); 721 722 extern LONGEST value_ptrdiff (struct value *arg1, struct value *arg2); 723 724 extern int value_must_coerce_to_target (struct value *arg1); 725 726 extern struct value *value_coerce_to_target (struct value *arg1); 727 728 extern struct value *value_coerce_array (struct value *arg1); 729 730 extern struct value *value_coerce_function (struct value *arg1); 731 732 extern struct value *value_ind (struct value *arg1); 733 734 extern struct value *value_addr (struct value *arg1); 735 736 extern struct value *value_ref (struct value *arg1); 737 738 extern struct value *value_assign (struct value *toval, 739 struct value *fromval); 740 741 extern struct value *value_pos (struct value *arg1); 742 743 extern struct value *value_neg (struct value *arg1); 744 745 extern struct value *value_complement (struct value *arg1); 746 747 extern struct value *value_struct_elt (struct value **argp, 748 struct value **args, 749 const char *name, int *static_memfuncp, 750 const char *err); 751 752 extern struct value *value_struct_elt_bitpos (struct value **argp, 753 int bitpos, 754 struct type *field_type, 755 const char *err); 756 757 extern struct value *value_aggregate_elt (struct type *curtype, 758 const char *name, 759 struct type *expect_type, 760 int want_address, 761 enum noside noside); 762 763 extern struct value *value_static_field (struct type *type, int fieldno); 764 765 enum oload_search_type { NON_METHOD, METHOD, BOTH }; 766 767 extern int find_overload_match (struct value **args, int nargs, 768 const char *name, 769 enum oload_search_type method, 770 struct value **objp, struct symbol *fsym, 771 struct value **valp, struct symbol **symp, 772 int *staticp, const int no_adl, 773 enum noside noside); 774 775 extern struct value *value_field (struct value *arg1, int fieldno); 776 777 extern struct value *value_primitive_field (struct value *arg1, LONGEST offset, 778 int fieldno, 779 struct type *arg_type); 780 781 782 extern struct type *value_rtti_indirect_type (struct value *, int *, LONGEST *, 783 int *); 784 785 extern struct value *value_full_object (struct value *, struct type *, int, 786 int, int); 787 788 extern struct value *value_cast_pointers (struct type *, struct value *, int); 789 790 extern struct value *value_cast (struct type *type, struct value *arg2); 791 792 extern struct value *value_reinterpret_cast (struct type *type, 793 struct value *arg); 794 795 extern struct value *value_dynamic_cast (struct type *type, struct value *arg); 796 797 extern struct value *value_zero (struct type *type, enum lval_type lv); 798 799 extern struct value *value_one (struct type *type); 800 801 extern struct value *value_repeat (struct value *arg1, int count); 802 803 extern struct value *value_subscript (struct value *array, LONGEST index); 804 805 extern struct value *value_bitstring_subscript (struct type *type, 806 struct value *bitstring, 807 LONGEST index); 808 809 extern struct value *register_value_being_returned (struct type *valtype, 810 struct regcache *retbuf); 811 812 extern int value_in (struct value *element, struct value *set); 813 814 extern int value_bit_index (struct type *type, const gdb_byte *addr, 815 int index); 816 817 extern enum return_value_convention 818 struct_return_convention (struct gdbarch *gdbarch, struct value *function, 819 struct type *value_type); 820 821 extern int using_struct_return (struct gdbarch *gdbarch, 822 struct value *function, 823 struct type *value_type); 824 825 extern struct value *evaluate_expression (struct expression *exp); 826 827 extern struct value *evaluate_type (struct expression *exp); 828 829 extern struct value *evaluate_subexp (struct type *expect_type, 830 struct expression *exp, 831 int *pos, enum noside noside); 832 833 extern struct value *evaluate_subexpression_type (struct expression *exp, 834 int subexp); 835 836 extern void fetch_subexp_value (struct expression *exp, int *pc, 837 struct value **valp, struct value **resultp, 838 struct value **val_chain, 839 int preserve_errors); 840 841 extern char *extract_field_op (struct expression *exp, int *subexp); 842 843 extern struct value *evaluate_subexp_with_coercion (struct expression *, 844 int *, enum noside); 845 846 extern struct value *parse_and_eval (const char *exp); 847 848 extern struct value *parse_to_comma_and_eval (const char **expp); 849 850 extern struct type *parse_and_eval_type (char *p, int length); 851 852 extern CORE_ADDR parse_and_eval_address (const char *exp); 853 854 extern LONGEST parse_and_eval_long (const char *exp); 855 856 extern void unop_promote (const struct language_defn *language, 857 struct gdbarch *gdbarch, 858 struct value **arg1); 859 860 extern void binop_promote (const struct language_defn *language, 861 struct gdbarch *gdbarch, 862 struct value **arg1, struct value **arg2); 863 864 extern struct value *access_value_history (int num); 865 866 extern struct value *value_of_internalvar (struct gdbarch *gdbarch, 867 struct internalvar *var); 868 869 extern int get_internalvar_integer (struct internalvar *var, LONGEST *l); 870 871 extern void set_internalvar (struct internalvar *var, struct value *val); 872 873 extern void set_internalvar_integer (struct internalvar *var, LONGEST l); 874 875 extern void set_internalvar_string (struct internalvar *var, 876 const char *string); 877 878 extern void clear_internalvar (struct internalvar *var); 879 880 extern void set_internalvar_component (struct internalvar *var, 881 LONGEST offset, 882 LONGEST bitpos, LONGEST bitsize, 883 struct value *newvalue); 884 885 extern struct internalvar *lookup_only_internalvar (const char *name); 886 887 extern struct internalvar *create_internalvar (const char *name); 888 889 extern VEC (char_ptr) *complete_internalvar (const char *name); 890 891 /* An internalvar can be dynamically computed by supplying a vector of 892 function pointers to perform various operations. */ 893 894 struct internalvar_funcs 895 { 896 /* Compute the value of the variable. The DATA argument passed to 897 the function is the same argument that was passed to 898 `create_internalvar_type_lazy'. */ 899 900 struct value *(*make_value) (struct gdbarch *arch, 901 struct internalvar *var, 902 void *data); 903 904 /* Update the agent expression EXPR with bytecode to compute the 905 value. VALUE is the agent value we are updating. The DATA 906 argument passed to this function is the same argument that was 907 passed to `create_internalvar_type_lazy'. If this pointer is 908 NULL, then the internalvar cannot be compiled to an agent 909 expression. */ 910 911 void (*compile_to_ax) (struct internalvar *var, 912 struct agent_expr *expr, 913 struct axs_value *value, 914 void *data); 915 916 /* If non-NULL, this is called to destroy DATA. The DATA argument 917 passed to this function is the same argument that was passed to 918 `create_internalvar_type_lazy'. */ 919 920 void (*destroy) (void *data); 921 }; 922 923 extern struct internalvar *create_internalvar_type_lazy (const char *name, 924 const struct internalvar_funcs *funcs, 925 void *data); 926 927 /* Compile an internal variable to an agent expression. VAR is the 928 variable to compile; EXPR and VALUE are the agent expression we are 929 updating. This will return 0 if there is no known way to compile 930 VAR, and 1 if VAR was successfully compiled. It may also throw an 931 exception on error. */ 932 933 extern int compile_internalvar_to_ax (struct internalvar *var, 934 struct agent_expr *expr, 935 struct axs_value *value); 936 937 extern struct internalvar *lookup_internalvar (const char *name); 938 939 extern int value_equal (struct value *arg1, struct value *arg2); 940 941 extern int value_equal_contents (struct value *arg1, struct value *arg2); 942 943 extern int value_less (struct value *arg1, struct value *arg2); 944 945 extern int value_logical_not (struct value *arg1); 946 947 /* C++ */ 948 949 extern struct value *value_of_this (const struct language_defn *lang); 950 951 extern struct value *value_of_this_silent (const struct language_defn *lang); 952 953 extern struct value *value_x_binop (struct value *arg1, struct value *arg2, 954 enum exp_opcode op, 955 enum exp_opcode otherop, 956 enum noside noside); 957 958 extern struct value *value_x_unop (struct value *arg1, enum exp_opcode op, 959 enum noside noside); 960 961 extern struct value *value_fn_field (struct value **arg1p, struct fn_field *f, 962 int j, struct type *type, LONGEST offset); 963 964 extern int binop_types_user_defined_p (enum exp_opcode op, 965 struct type *type1, 966 struct type *type2); 967 968 extern int binop_user_defined_p (enum exp_opcode op, struct value *arg1, 969 struct value *arg2); 970 971 extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1); 972 973 extern int destructor_name_p (const char *name, struct type *type); 974 975 extern void value_incref (struct value *val); 976 977 extern void value_free (struct value *val); 978 979 extern void free_all_values (void); 980 981 extern void free_value_chain (struct value *v); 982 983 extern void release_value (struct value *val); 984 985 extern void release_value_or_incref (struct value *val); 986 987 extern int record_latest_value (struct value *val); 988 989 extern void modify_field (struct type *type, gdb_byte *addr, 990 LONGEST fieldval, LONGEST bitpos, LONGEST bitsize); 991 992 extern void type_print (struct type *type, const char *varstring, 993 struct ui_file *stream, int show); 994 995 extern char *type_to_string (struct type *type); 996 997 extern gdb_byte *baseclass_addr (struct type *type, int index, 998 gdb_byte *valaddr, 999 struct value **valuep, int *errp); 1000 1001 extern void print_longest (struct ui_file *stream, int format, 1002 int use_local, LONGEST val); 1003 1004 extern void print_floating (const gdb_byte *valaddr, struct type *type, 1005 struct ui_file *stream); 1006 1007 extern void print_decimal_floating (const gdb_byte *valaddr, struct type *type, 1008 struct ui_file *stream); 1009 1010 extern void value_print (struct value *val, struct ui_file *stream, 1011 const struct value_print_options *options); 1012 1013 extern void value_print_array_elements (struct value *val, 1014 struct ui_file *stream, int format, 1015 enum val_prettyformat pretty); 1016 1017 extern struct value *value_release_to_mark (const struct value *mark); 1018 1019 extern void val_print (struct type *type, const gdb_byte *valaddr, 1020 LONGEST embedded_offset, CORE_ADDR address, 1021 struct ui_file *stream, int recurse, 1022 const struct value *val, 1023 const struct value_print_options *options, 1024 const struct language_defn *language); 1025 1026 extern void common_val_print (struct value *val, 1027 struct ui_file *stream, int recurse, 1028 const struct value_print_options *options, 1029 const struct language_defn *language); 1030 1031 extern int val_print_string (struct type *elttype, const char *encoding, 1032 CORE_ADDR addr, int len, 1033 struct ui_file *stream, 1034 const struct value_print_options *options); 1035 1036 extern void print_variable_and_value (const char *name, 1037 struct symbol *var, 1038 struct frame_info *frame, 1039 struct ui_file *stream, 1040 int indent); 1041 1042 extern void typedef_print (struct type *type, struct symbol *news, 1043 struct ui_file *stream); 1044 1045 extern char *internalvar_name (const struct internalvar *var); 1046 1047 extern void preserve_values (struct objfile *); 1048 1049 /* From values.c */ 1050 1051 extern struct value *value_copy (struct value *); 1052 1053 extern struct value *value_non_lval (struct value *); 1054 1055 extern void value_force_lval (struct value *, CORE_ADDR); 1056 1057 extern struct value *make_cv_value (int, int, struct value *); 1058 1059 extern void preserve_one_value (struct value *, struct objfile *, htab_t); 1060 1061 /* From valops.c */ 1062 1063 extern struct value *varying_to_slice (struct value *); 1064 1065 extern struct value *value_slice (struct value *, int, int); 1066 1067 extern struct value *value_literal_complex (struct value *, struct value *, 1068 struct type *); 1069 1070 extern struct value *find_function_in_inferior (const char *, 1071 struct objfile **); 1072 1073 extern struct value *value_allocate_space_in_inferior (int); 1074 1075 extern struct value *value_subscripted_rvalue (struct value *array, 1076 LONGEST index, int lowerbound); 1077 1078 /* User function handler. */ 1079 1080 typedef struct value *(*internal_function_fn) (struct gdbarch *gdbarch, 1081 const struct language_defn *language, 1082 void *cookie, 1083 int argc, 1084 struct value **argv); 1085 1086 void add_internal_function (const char *name, const char *doc, 1087 internal_function_fn handler, 1088 void *cookie); 1089 1090 struct value *call_internal_function (struct gdbarch *gdbarch, 1091 const struct language_defn *language, 1092 struct value *function, 1093 int argc, struct value **argv); 1094 1095 char *value_internal_function_name (struct value *); 1096 1097 extern struct value *value_of_xmethod (struct xmethod_worker *); 1098 1099 extern struct type *result_type_of_xmethod (struct value *method, 1100 int argc, struct value **argv); 1101 1102 extern struct value *call_xmethod (struct value *method, 1103 int argc, struct value **argv); 1104 1105 #endif /* !defined (VALUE_H) */ 1106