1/* Definitions for values of C expressions, for GDB. 2 3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 4 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 5 Free Software Foundation, Inc. 6 7 This file is part of GDB. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 21 22#if !defined (VALUE_H) 23#define VALUE_H 1 24 25#include "doublest.h" 26#include "frame.h" /* For struct frame_id. */ 27 28struct block; 29struct expression; 30struct regcache; 31struct symbol; 32struct type; 33struct ui_file; 34 35/* The structure which defines the type of a value. It should never 36 be possible for a program lval value to survive over a call to the 37 inferior (i.e. to be put into the history list or an internal 38 variable). */ 39 40struct value; 41 42/* Values are stored in a chain, so that they can be deleted easily 43 over calls to the inferior. Values assigned to internal variables 44 or put into the value history are taken off this list. */ 45 46struct value *value_next (struct value *); 47 48/* Type of the value. */ 49 50extern struct type *value_type (struct value *); 51 52/* This is being used to change the type of an existing value, that 53 code should instead be creating a new value with the changed type 54 (but possibly shared content). */ 55 56extern void deprecated_set_value_type (struct value *value, 57 struct type *type); 58 59/* Only used for bitfields; number of bits contained in them. */ 60 61extern int value_bitsize (struct value *); 62extern void set_value_bitsize (struct value *, int bit); 63 64/* Only used for bitfields; position of start of field. For 65 BITS_BIG_ENDIAN=0 targets, it is the position of the LSB. For 66 BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */ 67 68extern int value_bitpos (struct value *); 69extern void set_value_bitpos (struct value *, int bit); 70 71/* Describes offset of a value within lval of a structure in bytes. 72 If lval == lval_memory, this is an offset to the address. If lval 73 == lval_register, this is a further offset from location.address 74 within the registers structure. Note also the member 75 embedded_offset below. */ 76 77extern int value_offset (struct value *); 78extern void set_value_offset (struct value *, int offset); 79 80/* The comment from "struct value" reads: ``Is it modifiable? Only 81 relevant if lval != not_lval.''. Shouldn't the value instead be 82 not_lval and be done with it? */ 83 84extern int deprecated_value_modifiable (struct value *value); 85extern void deprecated_set_value_modifiable (struct value *value, 86 int modifiable); 87 88/* If a value represents a C++ object, then the `type' field gives the 89 object's compile-time type. If the object actually belongs to some 90 class derived from `type', perhaps with other base classes and 91 additional members, then `type' is just a subobject of the real 92 thing, and the full object is probably larger than `type' would 93 suggest. 94 95 If `type' is a dynamic class (i.e. one with a vtable), then GDB can 96 actually determine the object's run-time type by looking at the 97 run-time type information in the vtable. When this information is 98 available, we may elect to read in the entire object, for several 99 reasons: 100 101 - When printing the value, the user would probably rather see the 102 full object, not just the limited portion apparent from the 103 compile-time type. 104 105 - If `type' has virtual base classes, then even printing `type' 106 alone may require reaching outside the `type' portion of the 107 object to wherever the virtual base class has been stored. 108 109 When we store the entire object, `enclosing_type' is the run-time 110 type -- the complete object -- and `embedded_offset' is the offset 111 of `type' within that larger type, in bytes. The value_contents() 112 macro takes `embedded_offset' into account, so most GDB code 113 continues to see the `type' portion of the value, just as the 114 inferior would. 115 116 If `type' is a pointer to an object, then `enclosing_type' is a 117 pointer to the object's run-time type, and `pointed_to_offset' is 118 the offset in bytes from the full object to the pointed-to object 119 -- that is, the value `embedded_offset' would have if we followed 120 the pointer and fetched the complete object. (I don't really see 121 the point. Why not just determine the run-time type when you 122 indirect, and avoid the special case? The contents don't matter 123 until you indirect anyway.) 124 125 If we're not doing anything fancy, `enclosing_type' is equal to 126 `type', and `embedded_offset' is zero, so everything works 127 normally. */ 128 129extern struct type *value_enclosing_type (struct value *); 130extern struct value *value_change_enclosing_type (struct value *val, 131 struct type *new_type); 132extern int value_pointed_to_offset (struct value *value); 133extern void set_value_pointed_to_offset (struct value *value, int val); 134extern int value_embedded_offset (struct value *value); 135extern void set_value_embedded_offset (struct value *value, int val); 136 137/* If zero, contents of this value are in the contents field. If 138 nonzero, contents are in inferior memory at address in the 139 location.address field plus the offset field (and the lval field 140 should be lval_memory). 141 142 WARNING: This field is used by the code which handles watchpoints 143 (see breakpoint.c) to decide whether a particular value can be 144 watched by hardware watchpoints. If the lazy flag is set for some 145 member of a value chain, it is assumed that this member of the 146 chain doesn't need to be watched as part of watching the value 147 itself. This is how GDB avoids watching the entire struct or array 148 when the user wants to watch a single struct member or array 149 element. If you ever change the way lazy flag is set and reset, be 150 sure to consider this use as well! */ 151 152extern int value_lazy (struct value *); 153extern void set_value_lazy (struct value *value, int val); 154 155/* value_contents() and value_contents_raw() both return the address 156 of the gdb buffer used to hold a copy of the contents of the lval. 157 value_contents() is used when the contents of the buffer are needed 158 -- it uses value_fetch_lazy() to load the buffer from the process 159 being debugged if it hasn't already been loaded 160 (value_contents_writeable() is used when a writeable but fetched 161 buffer is required).. value_contents_raw() is used when data is 162 being stored into the buffer, or when it is certain that the 163 contents of the buffer are valid. 164 165 Note: The contents pointer is adjusted by the offset required to 166 get to the real subobject, if the value happens to represent 167 something embedded in a larger run-time object. */ 168 169extern gdb_byte *value_contents_raw (struct value *); 170 171/* Actual contents of the value. For use of this value; setting it 172 uses the stuff above. Not valid if lazy is nonzero. Target 173 byte-order. We force it to be aligned properly for any possible 174 value. Note that a value therefore extends beyond what is 175 declared here. */ 176 177extern const gdb_byte *value_contents (struct value *); 178extern gdb_byte *value_contents_writeable (struct value *); 179 180/* The ALL variants of the above two macros do not adjust the returned 181 pointer by the embedded_offset value. */ 182 183extern gdb_byte *value_contents_all_raw (struct value *); 184extern const gdb_byte *value_contents_all (struct value *); 185 186extern int value_fetch_lazy (struct value *val); 187extern int value_contents_equal (struct value *val1, struct value *val2); 188 189/* If nonzero, this is the value of a variable which does not actually 190 exist in the program. */ 191extern int value_optimized_out (struct value *value); 192extern void set_value_optimized_out (struct value *value, int val); 193 194/* Set or return field indicating whether a variable is initialized or 195 not, based on debugging information supplied by the compiler. 196 1 = initialized; 0 = uninitialized. */ 197extern int value_initialized (struct value *); 198extern void set_value_initialized (struct value *, int); 199 200/* While the following fields are per- VALUE .CONTENT .PIECE (i.e., a 201 single value might have multiple LVALs), this hacked interface is 202 limited to just the first PIECE. Expect further change. */ 203/* Type of value; either not an lval, or one of the various different 204 possible kinds of lval. */ 205extern enum lval_type *deprecated_value_lval_hack (struct value *); 206#define VALUE_LVAL(val) (*deprecated_value_lval_hack (val)) 207 208/* If lval == lval_memory, this is the address in the inferior. If 209 lval == lval_register, this is the byte offset into the registers 210 structure. */ 211extern CORE_ADDR *deprecated_value_address_hack (struct value *); 212#define VALUE_ADDRESS(val) (*deprecated_value_address_hack (val)) 213 214/* Pointer to internal variable. */ 215extern struct internalvar **deprecated_value_internalvar_hack (struct value *); 216#define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val)) 217 218/* Frame register value is relative to. This will be described in the 219 lval enum above as "lval_register". */ 220extern struct frame_id *deprecated_value_frame_id_hack (struct value *); 221#define VALUE_FRAME_ID(val) (*deprecated_value_frame_id_hack (val)) 222 223/* Register number if the value is from a register. */ 224extern short *deprecated_value_regnum_hack (struct value *); 225#define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val)) 226 227/* Convert a REF to the object referenced. */ 228 229extern struct value *coerce_ref (struct value *value); 230 231/* If ARG is an array, convert it to a pointer. 232 If ARG is an enum, convert it to an integer. 233 If ARG is a function, convert it to a function pointer. 234 235 References are dereferenced. */ 236 237extern struct value *coerce_array (struct value *value); 238extern struct value *coerce_number (struct value *value); 239 240/* If ARG is an enum, convert it to an integer. */ 241 242extern struct value *coerce_enum (struct value *value); 243 244/* Internal variables (variables for convenience of use of debugger) 245 are recorded as a chain of these structures. */ 246 247struct internalvar 248{ 249 struct internalvar *next; 250 char *name; 251 struct value *value; 252 int endian; 253}; 254 255 256 257#include "symtab.h" 258#include "gdbtypes.h" 259#include "expression.h" 260 261struct frame_info; 262struct fn_field; 263 264extern void print_address_demangle (CORE_ADDR, struct ui_file *, int); 265 266extern LONGEST value_as_long (struct value *val); 267extern DOUBLEST value_as_double (struct value *val); 268extern CORE_ADDR value_as_address (struct value *val); 269 270extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr); 271extern DOUBLEST unpack_double (struct type *type, const gdb_byte *valaddr, 272 int *invp); 273extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr); 274extern LONGEST unpack_field_as_long (struct type *type, 275 const gdb_byte *valaddr, 276 int fieldno); 277 278extern void pack_long (gdb_byte *buf, struct type *type, LONGEST num); 279 280extern struct value *value_from_longest (struct type *type, LONGEST num); 281extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr); 282extern struct value *value_from_double (struct type *type, DOUBLEST num); 283extern struct value *value_from_string (char *string); 284 285extern struct value *value_at (struct type *type, CORE_ADDR addr); 286extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr); 287 288extern struct value *default_value_from_register (struct type *type, 289 int regnum, 290 struct frame_info *frame); 291 292extern struct value *value_from_register (struct type *type, int regnum, 293 struct frame_info *frame); 294 295extern CORE_ADDR address_from_register (struct type *type, int regnum, 296 struct frame_info *frame); 297 298extern struct value *value_of_variable (struct symbol *var, struct block *b); 299 300extern struct value *value_of_register (int regnum, struct frame_info *frame); 301 302extern int symbol_read_needs_frame (struct symbol *); 303 304extern struct value *read_var_value (struct symbol *var, 305 struct frame_info *frame); 306 307extern struct value *locate_var_value (struct symbol *var, 308 struct frame_info *frame); 309 310extern struct value *allocate_value (struct type *type); 311 312extern struct value *allocate_repeat_value (struct type *type, int count); 313 314extern struct value *value_mark (void); 315 316extern void value_free_to_mark (struct value *mark); 317 318extern struct value *value_string (char *ptr, int len); 319extern struct value *value_bitstring (char *ptr, int len); 320 321extern struct value *value_array (int lowbound, int highbound, 322 struct value **elemvec); 323 324extern struct value *value_concat (struct value *arg1, struct value *arg2); 325 326extern struct value *value_binop (struct value *arg1, struct value *arg2, 327 enum exp_opcode op); 328 329extern struct value *value_add (struct value *arg1, struct value *arg2); 330 331extern struct value *value_sub (struct value *arg1, struct value *arg2); 332 333extern struct value *value_coerce_array (struct value *arg1); 334 335extern struct value *value_coerce_function (struct value *arg1); 336 337extern struct value *value_ind (struct value *arg1); 338 339extern struct value *value_addr (struct value *arg1); 340 341extern struct value *value_ref (struct value *arg1); 342 343extern struct value *value_assign (struct value *toval, 344 struct value *fromval); 345 346extern struct value *value_pos (struct value *arg1); 347 348extern struct value *value_neg (struct value *arg1); 349 350extern struct value *value_complement (struct value *arg1); 351 352extern struct value *value_struct_elt (struct value **argp, 353 struct value **args, 354 char *name, int *static_memfuncp, 355 char *err); 356 357extern struct value *value_aggregate_elt (struct type *curtype, 358 char *name, 359 int want_address, 360 enum noside noside); 361 362extern struct value *value_static_field (struct type *type, int fieldno); 363 364extern struct fn_field *value_find_oload_method_list (struct value **, char *, 365 int, int *, 366 struct type **, int *); 367 368extern int find_overload_match (struct type **arg_types, int nargs, 369 char *name, int method, int lax, 370 struct value **objp, struct symbol *fsym, 371 struct value **valp, struct symbol **symp, 372 int *staticp); 373 374extern struct value *value_field (struct value *arg1, int fieldno); 375 376extern struct value *value_primitive_field (struct value *arg1, int offset, 377 int fieldno, 378 struct type *arg_type); 379 380 381extern struct type *value_rtti_target_type (struct value *, int *, int *, 382 int *); 383 384extern struct value *value_full_object (struct value *, struct type *, int, 385 int, int); 386 387extern struct value *value_cast_pointers (struct type *, struct value *); 388 389extern struct value *value_cast (struct type *type, struct value *arg2); 390 391extern struct value *value_zero (struct type *type, enum lval_type lv); 392 393extern struct value *value_repeat (struct value *arg1, int count); 394 395extern struct value *value_subscript (struct value *array, struct value *idx); 396 397extern struct value *register_value_being_returned (struct type *valtype, 398 struct regcache *retbuf); 399 400extern struct value *value_in (struct value *element, struct value *set); 401 402extern int value_bit_index (struct type *type, const gdb_byte *addr, 403 int index); 404 405extern int using_struct_return (struct type *value_type, int gcc_p); 406 407extern struct value *evaluate_expression (struct expression *exp); 408 409extern struct value *evaluate_type (struct expression *exp); 410 411extern struct value *evaluate_subexp_with_coercion (struct expression *, 412 int *, enum noside); 413 414extern struct value *parse_and_eval (char *exp); 415 416extern struct value *parse_to_comma_and_eval (char **expp); 417 418extern struct type *parse_and_eval_type (char *p, int length); 419 420extern CORE_ADDR parse_and_eval_address (char *exp); 421 422extern CORE_ADDR parse_and_eval_address_1 (char **expptr); 423 424extern LONGEST parse_and_eval_long (char *exp); 425 426extern struct value *access_value_history (int num); 427 428extern struct value *value_of_internalvar (struct internalvar *var); 429 430extern void set_internalvar (struct internalvar *var, struct value *val); 431 432extern void set_internalvar_component (struct internalvar *var, 433 int offset, 434 int bitpos, int bitsize, 435 struct value *newvalue); 436 437extern struct internalvar *lookup_internalvar (char *name); 438 439extern int value_equal (struct value *arg1, struct value *arg2); 440 441extern int value_less (struct value *arg1, struct value *arg2); 442 443extern int value_logical_not (struct value *arg1); 444 445/* C++ */ 446 447extern struct value *value_of_this (int complain); 448 449extern struct value *value_x_binop (struct value *arg1, struct value *arg2, 450 enum exp_opcode op, 451 enum exp_opcode otherop, 452 enum noside noside); 453 454extern struct value *value_x_unop (struct value *arg1, enum exp_opcode op, 455 enum noside noside); 456 457extern struct value *value_fn_field (struct value **arg1p, struct fn_field *f, 458 int j, struct type *type, int offset); 459 460extern int binop_user_defined_p (enum exp_opcode op, struct value *arg1, 461 struct value *arg2); 462 463extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1); 464 465extern int destructor_name_p (const char *name, const struct type *type); 466 467#define value_free(val) xfree (val) 468 469extern void free_all_values (void); 470 471extern void release_value (struct value *val); 472 473extern int record_latest_value (struct value *val); 474 475extern void modify_field (gdb_byte *addr, LONGEST fieldval, int bitpos, 476 int bitsize); 477 478extern void type_print (struct type *type, char *varstring, 479 struct ui_file *stream, int show); 480 481extern gdb_byte *baseclass_addr (struct type *type, int index, 482 gdb_byte *valaddr, 483 struct value **valuep, int *errp); 484 485extern void print_longest (struct ui_file *stream, int format, 486 int use_local, LONGEST val); 487 488extern void print_floating (const gdb_byte *valaddr, struct type *type, 489 struct ui_file *stream); 490 491extern int value_print (struct value *val, struct ui_file *stream, int format, 492 enum val_prettyprint pretty); 493 494extern void value_print_array_elements (struct value *val, 495 struct ui_file *stream, int format, 496 enum val_prettyprint pretty); 497 498extern struct value *value_release_to_mark (struct value *mark); 499 500extern int val_print (struct type *type, const gdb_byte *valaddr, 501 int embedded_offset, CORE_ADDR address, 502 struct ui_file *stream, int format, 503 int deref_ref, int recurse, 504 enum val_prettyprint pretty); 505 506extern int common_val_print (struct value *val, 507 struct ui_file *stream, int format, 508 int deref_ref, int recurse, 509 enum val_prettyprint pretty); 510 511extern int val_print_string (CORE_ADDR addr, int len, int width, 512 struct ui_file *stream); 513 514extern void print_variable_value (struct symbol *var, 515 struct frame_info *frame, 516 struct ui_file *stream); 517 518extern int check_field (struct value *, const char *); 519 520extern void typedef_print (struct type *type, struct symbol *news, 521 struct ui_file *stream); 522 523extern char *internalvar_name (struct internalvar *var); 524 525extern void preserve_values (struct objfile *); 526 527/* From values.c */ 528 529extern struct value *value_copy (struct value *); 530 531/* From valops.c */ 532 533extern struct value *varying_to_slice (struct value *); 534 535extern struct value *value_slice (struct value *, int, int); 536 537extern struct value *value_literal_complex (struct value *, struct value *, 538 struct type *); 539 540extern void find_rt_vbase_offset (struct type *, struct type *, 541 const gdb_byte *, int, int *, int *); 542 543extern struct value *find_function_in_inferior (const char *); 544 545extern struct value *value_allocate_space_in_inferior (int); 546 547extern struct value *value_of_local (const char *name, int complain); 548 549#endif /* !defined (VALUE_H) */ 550