value.h revision 46283
1/* Definitions for values of C expressions, for GDB. 2 Copyright 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996 3 Free Software Foundation, Inc. 4 5This file is part of GDB. 6 7This program is free software; you can redistribute it and/or modify 8it under the terms of the GNU General Public License as published by 9the Free Software Foundation; either version 2 of the License, or 10(at your option) any later version. 11 12This program is distributed in the hope that it will be useful, 13but WITHOUT ANY WARRANTY; without even the implied warranty of 14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15GNU General Public License for more details. 16 17You should have received a copy of the GNU General Public License 18along with this program; if not, write to the Free Software 19Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 20 21#if !defined (VALUE_H) 22#define VALUE_H 1 23 24/* 25 * The structure which defines the type of a value. It should never 26 * be possible for a program lval value to survive over a call to the inferior 27 * (ie to be put into the history list or an internal variable). 28 */ 29enum lval_type { 30 /* Not an lval. */ 31 not_lval, 32 /* In memory. Could be a saved register. */ 33 lval_memory, 34 /* In a register. */ 35 lval_register, 36 /* In a gdb internal variable. */ 37 lval_internalvar, 38 /* Part of a gdb internal variable (structure field). */ 39 lval_internalvar_component, 40 /* In a register series in a frame not the current one, which may have been 41 partially saved or saved in different places (otherwise would be 42 lval_register or lval_memory). */ 43 lval_reg_frame_relative 44}; 45 46struct value 47 { 48 /* Type of value; either not an lval, or one of the various 49 different possible kinds of lval. */ 50 enum lval_type lval; 51 /* Is it modifiable? Only relevant if lval != not_lval. */ 52 int modifiable; 53 /* Location of value (if lval). */ 54 union 55 { 56 /* Address in inferior or byte of registers structure. */ 57 CORE_ADDR address; 58 /* Pointer to internal variable. */ 59 struct internalvar *internalvar; 60 /* Number of register. Only used with 61 lval_reg_frame_relative. */ 62 int regnum; 63 } location; 64 /* Describes offset of a value within lval of a structure in bytes. 65 This is used in retrieving contents from target memory. [Note also 66 the member embedded_offset below.] */ 67 int offset; 68 /* Only used for bitfields; number of bits contained in them. */ 69 int bitsize; 70 /* Only used for bitfields; position of start of field. 71 For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB. 72 For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */ 73 int bitpos; 74 /* Frame value is relative to. In practice, this address is only 75 used if the value is stored in several registers in other than 76 the current frame, and these registers have not all been saved 77 at the same place in memory. This will be described in the 78 lval enum above as "lval_reg_frame_relative". */ 79 CORE_ADDR frame_addr; 80 /* Type of the value. */ 81 struct type *type; 82 /* Type of the enclosing object if this is an embedded subobject. 83 The member embedded_offset gives the real position of the subobject 84 if type is not the same as enclosing_type. 85 86 If the type field is a pointer type, then enclosing_type is 87 a pointer type pointing to the real (enclosing) type of the target 88 object. */ 89 struct type *enclosing_type; 90 /* Values are stored in a chain, so that they can be deleted 91 easily over calls to the inferior. Values assigned to internal 92 variables or put into the value history are taken off this 93 list. */ 94 struct value *next; 95 96 /* ??? When is this used? */ 97 union { 98 CORE_ADDR memaddr; 99 char *myaddr; 100 } substring_addr; 101 102 /* Register number if the value is from a register. Is not kept 103 if you take a field of a structure that is stored in a 104 register. Shouldn't it be? */ 105 short regno; 106 /* If zero, contents of this value are in the contents field. 107 If nonzero, contents are in inferior memory at address 108 in the location.address field plus the offset field 109 (and the lval field should be lval_memory). */ 110 char lazy; 111 /* If nonzero, this is the value of a variable which does not 112 actually exist in the program. */ 113 char optimized_out; 114 /* If this value represents an object that is embedded inside a 115 larger object (e.g., a base subobject in C++), this gives the 116 offset (in bytes) from the start of the contents buffer where 117 the embedded object begins. This is required because some C++ 118 runtime implementations lay out objects (especially virtual bases 119 with possibly negative offsets to ancestors). 120 Note: This may be positive or negative! Also note that this offset 121 is not used when retrieving contents from target memory; the entire 122 enclosing object has to be retrieved always, and the offset for 123 that is given by the member offset above. */ 124 int embedded_offset; 125 /* If this value represents a pointer to an object that is embedded 126 in another object, this gives the embedded_offset of the object 127 that is pointed to. */ 128 int pointed_to_offset; 129 /* The BFD section associated with this value. */ 130 asection *bfd_section; 131 /* Actual contents of the value. For use of this value; setting 132 it uses the stuff above. Not valid if lazy is nonzero. 133 Target byte-order. We force it to be aligned properly for any 134 possible value. Note that a value therefore extends beyond 135 what is declared here. */ 136 union { 137 long contents[1]; 138 double force_double_align; 139 LONGEST force_longlong_align; 140 char *literal_data; 141 } aligner; 142 /* Do not add any new members here -- contents above will trash them */ 143 }; 144 145typedef struct value *value_ptr; 146 147#define VALUE_TYPE(val) (val)->type 148#define VALUE_ENCLOSING_TYPE(val) (val)->enclosing_type 149#define VALUE_LAZY(val) (val)->lazy 150/* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of 151 the gdb buffer used to hold a copy of the contents of the lval. 152 VALUE_CONTENTS is used when the contents of the buffer are needed -- 153 it uses value_fetch_lazy() to load the buffer from the process being 154 debugged if it hasn't already been loaded. VALUE_CONTENTS_RAW is 155 used when data is being stored into the buffer, or when it is 156 certain that the contents of the buffer are valid. 157 Note: The contents pointer is adjusted by the offset required to 158 get to the real subobject, if the value happens to represent 159 something embedded in a larger run-time object. */ 160 161#define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents + (val)->embedded_offset) 162#define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\ 163 VALUE_CONTENTS_RAW(val)) 164 165/* The ALL variants of the above two macros do not adjust the returned 166 pointer by the embedded_offset value. */ 167 168#define VALUE_CONTENTS_ALL_RAW(val) ((char *) (val)->aligner.contents) 169#define VALUE_CONTENTS_ALL(val) ((void) (VALUE_LAZY(val) && value_fetch_lazy(val)),\ 170 VALUE_CONTENTS_ALL_RAW(val)) 171 172 173extern int value_fetch_lazy PARAMS ((value_ptr val)); 174 175#define VALUE_LVAL(val) (val)->lval 176#define VALUE_ADDRESS(val) (val)->location.address 177#define VALUE_INTERNALVAR(val) (val)->location.internalvar 178#define VALUE_FRAME_REGNUM(val) ((val)->location.regnum) 179#define VALUE_FRAME(val) ((val)->frame_addr) 180#define VALUE_OFFSET(val) (val)->offset 181#define VALUE_BITSIZE(val) (val)->bitsize 182#define VALUE_BITPOS(val) (val)->bitpos 183#define VALUE_NEXT(val) (val)->next 184#define VALUE_REGNO(val) (val)->regno 185#define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out) 186#define VALUE_EMBEDDED_OFFSET(val) ((val)->embedded_offset) 187#define VALUE_POINTED_TO_OFFSET(val) ((val)->pointed_to_offset) 188#define VALUE_BFD_SECTION(val) ((val)->bfd_section) 189 190/* Convert a REF to the object referenced. */ 191 192#define COERCE_REF(arg) \ 193do { struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg));\ 194 if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) \ 195 arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), \ 196 unpack_long (VALUE_TYPE (arg), \ 197 VALUE_CONTENTS (arg)), \ 198 VALUE_BFD_SECTION (arg)); \ 199 } while (0) 200 201/* If ARG is an array, convert it to a pointer. 202 If ARG is an enum, convert it to an integer. 203 If ARG is a function, convert it to a function pointer. 204 205 References are dereferenced. */ 206 207#define COERCE_ARRAY(arg) \ 208do { COERCE_REF(arg); \ 209 if (current_language->c_style_arrays \ 210 && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \ 211 arg = value_coerce_array (arg); \ 212 if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC) \ 213 arg = value_coerce_function (arg); \ 214} while (0) 215 216#define COERCE_NUMBER(arg) \ 217 do { COERCE_ARRAY(arg); COERCE_ENUM(arg); } while (0) 218 219#define COERCE_VARYING_ARRAY(arg, real_arg_type) \ 220{ if (chill_varying_type (real_arg_type)) \ 221 arg = varying_to_slice (arg), real_arg_type = VALUE_TYPE (arg); } 222 223/* If ARG is an enum, convert it to an integer. */ 224 225#define COERCE_ENUM(arg) { \ 226 if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM) \ 227 arg = value_cast (builtin_type_unsigned_int, arg); \ 228} 229 230/* Internal variables (variables for convenience of use of debugger) 231 are recorded as a chain of these structures. */ 232 233struct internalvar 234{ 235 struct internalvar *next; 236 char *name; 237 value_ptr value; 238}; 239 240/* Pointer to member function. Depends on compiler implementation. */ 241 242#define METHOD_PTR_IS_VIRTUAL(ADDR) ((ADDR) & 0x80000000) 243#define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET)) 244#define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR)) 245 246 247#include "symtab.h" 248#include "gdbtypes.h" 249#include "expression.h" 250 251#ifdef __STDC__ 252struct frame_info; 253struct fn_field; 254#endif 255 256extern void 257print_address_demangle PARAMS ((CORE_ADDR, GDB_FILE *, int)); 258 259extern LONGEST value_as_long PARAMS ((value_ptr val)); 260 261extern DOUBLEST value_as_double PARAMS ((value_ptr val)); 262 263extern CORE_ADDR value_as_pointer PARAMS ((value_ptr val)); 264 265extern LONGEST unpack_long PARAMS ((struct type *type, char *valaddr)); 266 267extern DOUBLEST unpack_double PARAMS ((struct type *type, char *valaddr, 268 int *invp)); 269 270extern CORE_ADDR unpack_pointer PARAMS ((struct type *type, char *valaddr)); 271 272extern LONGEST unpack_field_as_long PARAMS ((struct type *type, char *valaddr, 273 int fieldno)); 274 275extern value_ptr value_from_longest PARAMS ((struct type *type, LONGEST num)); 276 277extern value_ptr value_from_double PARAMS ((struct type *type, DOUBLEST num)); 278 279extern value_ptr value_at PARAMS ((struct type *type, CORE_ADDR addr, asection *sect)); 280 281extern value_ptr value_at_lazy PARAMS ((struct type *type, CORE_ADDR addr, asection *sect)); 282 283extern value_ptr value_from_register PARAMS ((struct type *type, int regnum, 284 struct frame_info * frame)); 285 286extern value_ptr value_of_variable PARAMS ((struct symbol *var, 287 struct block *b)); 288 289extern value_ptr value_of_register PARAMS ((int regnum)); 290 291extern int symbol_read_needs_frame PARAMS ((struct symbol *)); 292 293extern value_ptr read_var_value PARAMS ((struct symbol *var, 294 struct frame_info *frame)); 295 296extern value_ptr locate_var_value PARAMS ((struct symbol *var, 297 struct frame_info *frame)); 298 299extern value_ptr allocate_value PARAMS ((struct type *type)); 300 301extern value_ptr allocate_repeat_value PARAMS ((struct type *type, int count)); 302 303extern value_ptr value_mark PARAMS ((void)); 304 305extern void value_free_to_mark PARAMS ((value_ptr mark)); 306 307extern value_ptr value_string PARAMS ((char *ptr, int len)); 308extern value_ptr value_bitstring PARAMS ((char *ptr, int len)); 309 310extern value_ptr value_array PARAMS ((int lowbound, int highbound, 311 value_ptr *elemvec)); 312 313extern value_ptr value_concat PARAMS ((value_ptr arg1, value_ptr arg2)); 314 315extern value_ptr value_binop PARAMS ((value_ptr arg1, value_ptr arg2, 316 enum exp_opcode op)); 317 318extern value_ptr value_add PARAMS ((value_ptr arg1, value_ptr arg2)); 319 320extern value_ptr value_sub PARAMS ((value_ptr arg1, value_ptr arg2)); 321 322extern value_ptr value_coerce_array PARAMS ((value_ptr arg1)); 323 324extern value_ptr value_coerce_function PARAMS ((value_ptr arg1)); 325 326extern value_ptr value_ind PARAMS ((value_ptr arg1)); 327 328extern value_ptr value_addr PARAMS ((value_ptr arg1)); 329 330extern value_ptr value_assign PARAMS ((value_ptr toval, value_ptr fromval)); 331 332extern value_ptr value_neg PARAMS ((value_ptr arg1)); 333 334extern value_ptr value_complement PARAMS ((value_ptr arg1)); 335 336extern value_ptr value_struct_elt PARAMS ((value_ptr *argp, value_ptr *args, 337 char *name, 338 int *static_memfuncp, char *err)); 339 340extern value_ptr value_struct_elt_for_reference PARAMS ((struct type *domain, 341 int offset, 342 struct type *curtype, 343 char *name, 344 struct type *intype)); 345 346extern value_ptr value_static_field PARAMS ((struct type *type, int fieldno)); 347 348extern struct fn_field * 349value_find_oload_method_list PARAMS ((value_ptr *, char *, int, int *, int *, struct type **, int *)); 350 351extern value_ptr value_field PARAMS ((value_ptr arg1, int fieldno)); 352 353extern value_ptr value_primitive_field PARAMS ((value_ptr arg1, int offset, 354 int fieldno, 355 struct type *arg_type)); 356 357extern struct type * 358value_rtti_type PARAMS ((value_ptr, int *, int *, int *)); 359 360extern struct type * 361value_rtti_target_type PARAMS ((value_ptr, int *, int *, int *)); 362 363extern value_ptr 364value_full_object PARAMS ((value_ptr, struct type *, int, int, int)); 365 366extern value_ptr value_cast PARAMS ((struct type *type, value_ptr arg2)); 367 368extern value_ptr value_zero PARAMS ((struct type *type, enum lval_type lv)); 369 370extern value_ptr value_repeat PARAMS ((value_ptr arg1, int count)); 371 372extern value_ptr value_subscript PARAMS ((value_ptr array, value_ptr idx)); 373 374extern value_ptr value_from_vtable_info PARAMS ((value_ptr arg, 375 struct type *type)); 376 377extern value_ptr value_being_returned PARAMS ((struct type *valtype, 378 char retbuf[REGISTER_BYTES], 379 int struct_return)); 380 381extern value_ptr value_in PARAMS ((value_ptr element, value_ptr set)); 382 383extern int value_bit_index PARAMS ((struct type *type, char *addr, int index)); 384 385extern int using_struct_return PARAMS ((value_ptr function, CORE_ADDR funcaddr, 386 struct type *value_type, int gcc_p)); 387 388extern void set_return_value PARAMS ((value_ptr val)); 389 390extern value_ptr evaluate_expression PARAMS ((struct expression *exp)); 391 392extern value_ptr evaluate_type PARAMS ((struct expression *exp)); 393 394extern value_ptr evaluate_subexp_with_coercion PARAMS ((struct expression *, 395 int *, enum noside)); 396 397extern value_ptr parse_and_eval PARAMS ((char *exp)); 398 399extern value_ptr parse_to_comma_and_eval PARAMS ((char **expp)); 400 401extern struct type *parse_and_eval_type PARAMS ((char *p, int length)); 402 403extern CORE_ADDR parse_and_eval_address PARAMS ((char *exp)); 404 405extern CORE_ADDR parse_and_eval_address_1 PARAMS ((char **expptr)); 406 407extern value_ptr access_value_history PARAMS ((int num)); 408 409extern value_ptr value_of_internalvar PARAMS ((struct internalvar *var)); 410 411extern void set_internalvar PARAMS ((struct internalvar *var, value_ptr val)); 412 413extern void set_internalvar_component PARAMS ((struct internalvar *var, 414 int offset, 415 int bitpos, int bitsize, 416 value_ptr newvalue)); 417 418extern struct internalvar *lookup_internalvar PARAMS ((char *name)); 419 420extern int value_equal PARAMS ((value_ptr arg1, value_ptr arg2)); 421 422extern int value_less PARAMS ((value_ptr arg1, value_ptr arg2)); 423 424extern int value_logical_not PARAMS ((value_ptr arg1)); 425 426/* C++ */ 427 428extern value_ptr value_of_this PARAMS ((int complain)); 429 430extern value_ptr value_x_binop PARAMS ((value_ptr arg1, value_ptr arg2, 431 enum exp_opcode op, 432 enum exp_opcode otherop, 433 enum noside noside)); 434 435extern value_ptr value_x_unop PARAMS ((value_ptr arg1, enum exp_opcode op, 436 enum noside noside)); 437 438extern value_ptr value_fn_field PARAMS ((value_ptr *arg1p, struct fn_field *f, 439 int j, 440 struct type* type, int offset)); 441 442extern value_ptr value_virtual_fn_field PARAMS ((value_ptr *arg1p, 443 struct fn_field *f, int j, 444 struct type *type, 445 int offset)); 446 447extern int binop_user_defined_p PARAMS ((enum exp_opcode op, 448 value_ptr arg1, value_ptr arg2)); 449 450extern int unop_user_defined_p PARAMS ((enum exp_opcode op, value_ptr arg1)); 451 452extern int destructor_name_p PARAMS ((const char *name, 453 const struct type *type)); 454 455#define value_free(val) free ((PTR)val) 456 457extern void free_all_values PARAMS ((void)); 458 459extern void release_value PARAMS ((value_ptr val)); 460 461extern int record_latest_value PARAMS ((value_ptr val)); 462 463extern void registers_changed PARAMS ((void)); 464 465extern void read_register_bytes PARAMS ((int regbyte, char *myaddr, int len)); 466 467extern void write_register_bytes PARAMS ((int regbyte, char *myaddr, int len)); 468 469extern void 470read_register_gen PARAMS ((int regno, char *myaddr)); 471 472extern CORE_ADDR 473read_register PARAMS ((int regno)); 474 475extern CORE_ADDR 476read_register_pid PARAMS ((int regno, int pid)); 477 478extern void 479write_register PARAMS ((int regno, LONGEST val)); 480 481extern void 482write_register_pid PARAMS ((int regno, CORE_ADDR val, int pid)); 483 484extern void 485supply_register PARAMS ((int regno, char *val)); 486 487extern void 488get_saved_register PARAMS ((char *raw_buffer, int *optimized, 489 CORE_ADDR *addrp, struct frame_info *frame, 490 int regnum, enum lval_type *lval)); 491 492extern void 493modify_field PARAMS ((char *addr, LONGEST fieldval, int bitpos, int bitsize)); 494 495extern void 496type_print PARAMS ((struct type *type, char *varstring, GDB_FILE *stream, 497 int show)); 498 499extern char *baseclass_addr PARAMS ((struct type *type, int index, 500 char *valaddr, 501 value_ptr *valuep, int *errp)); 502 503extern void 504print_longest PARAMS ((GDB_FILE *stream, int format, int use_local, 505 LONGEST val)); 506 507extern void 508print_floating PARAMS ((char *valaddr, struct type *type, GDB_FILE *stream)); 509 510extern int value_print PARAMS ((value_ptr val, GDB_FILE *stream, int format, 511 enum val_prettyprint pretty)); 512 513extern void 514value_print_array_elements PARAMS ((value_ptr val, GDB_FILE* stream, 515 int format, enum val_prettyprint pretty)); 516 517extern value_ptr 518value_release_to_mark PARAMS ((value_ptr mark)); 519 520extern int 521val_print PARAMS ((struct type *type, char *valaddr, int embedded_offset, CORE_ADDR address, 522 GDB_FILE *stream, int format, int deref_ref, 523 int recurse, enum val_prettyprint pretty)); 524 525extern int 526val_print_string PARAMS ((CORE_ADDR addr, int len, int width, GDB_FILE *stream)); 527 528extern void 529print_variable_value PARAMS ((struct symbol *var, struct frame_info *frame, 530 GDB_FILE *stream)); 531 532extern int check_field PARAMS ((value_ptr, const char *)); 533 534extern void 535c_typedef_print PARAMS ((struct type *type, struct symbol *news, GDB_FILE *stream)); 536 537extern char * 538internalvar_name PARAMS ((struct internalvar *var)); 539 540extern void 541clear_value_history PARAMS ((void)); 542 543extern void 544clear_internalvars PARAMS ((void)); 545 546/* From values.c */ 547 548extern value_ptr value_copy PARAMS ((value_ptr)); 549 550extern int baseclass_offset PARAMS ((struct type *, int, char *, CORE_ADDR)); 551 552/* From valops.c */ 553 554extern value_ptr varying_to_slice PARAMS ((value_ptr)); 555 556extern value_ptr value_slice PARAMS ((value_ptr, int, int)); 557 558extern value_ptr call_function_by_hand PARAMS ((value_ptr, int, value_ptr *)); 559 560extern value_ptr value_literal_complex PARAMS ((value_ptr, value_ptr, struct type*)); 561 562extern void find_rt_vbase_offset PARAMS ((struct type *, struct type *, char *, int, int *, int *)); 563 564extern value_ptr find_function_in_inferior PARAMS ((char *)); 565 566extern value_ptr value_allocate_space_in_inferior PARAMS ((int)); 567 568#endif /* !defined (VALUE_H) */ 569