gdb/value.h

   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
   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 2 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, write to the Free Software
  19 Foundation, 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  */
  29 enum 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
  46 struct 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 a structure in bytes.  */
  65     int offset;
  66     /* Only used for bitfields; number of bits contained in them.  */
  67     int bitsize;
  68     /* Only used for bitfields; position of start of field.
  69        For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB.
  70        For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */
  71     int bitpos;
  72     /* Frame value is relative to.  In practice, this address is only
  73        used if the value is stored in several registers in other than
  74        the current frame, and these registers have not all been saved
  75        at the same place in memory.  This will be described in the
  76        lval enum above as "lval_reg_frame_relative".  */
  77     CORE_ADDR frame_addr;
  78     /* Type of the value.  */
  79     struct type *type;
  80     /* Values are stored in a chain, so that they can be deleted
  81        easily over calls to the inferior.  Values assigned to internal
  82        variables or put into the value history are taken off this
  83        list.  */
  84     struct value *next;
  85
  86     /* ??? When is this used?  */
  87     union {
  88       CORE_ADDR memaddr;
  89       char *myaddr;
  90     } substring_addr;
  91
  92     /* Register number if the value is from a register.  Is not kept
  93        if you take a field of a structure that is stored in a
  94        register.  Shouldn't it be?  */
  95     short regno;
  96     /* If zero, contents of this value are in the contents field.
  97        If nonzero, contents are in inferior memory at address
  98        in the location.address field plus the offset field
  99        (and the lval field should be lval_memory).  */
 100     char lazy;
 101     /* If nonzero, this is the value of a variable which does not
 102        actually exist in the program.  */
 103     char optimized_out;
 104     /* Actual contents of the value.  For use of this value; setting
 105        it uses the stuff above.  Not valid if lazy is nonzero.
 106        Target byte-order.  We force it to be aligned properly for any
 107        possible value.  */
 108     union {
 109       long contents[1];
 110       double force_double_align;
 111       LONGEST force_longlong_align;
 112       char *literal_data;
 113     } aligner;
 114
 115   };
 116
 117 typedef struct value *value_ptr;
 118
 119 #define VALUE_TYPE(val) (val)->type
 120 #define VALUE_LAZY(val) (val)->lazy
 121 /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of
 122    the gdb buffer used to hold a copy of the contents of the lval.
 123    VALUE_CONTENTS is used when the contents of the buffer are needed --
 124    it uses value_fetch_lazy() to load the buffer from the process being
 125    debugged if it hasn't already been loaded.  VALUE_CONTENTS_RAW is
 126    used when data is being stored into the buffer, or when it is
 127    certain that the contents of the buffer are valid.  */
 128 #define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents)
 129 #define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\
 130                              VALUE_CONTENTS_RAW(val))
 131 extern int value_fetch_lazy PARAMS ((value_ptr val));
 132
 133 #define VALUE_LVAL(val) (val)->lval
 134 #define VALUE_ADDRESS(val) (val)->location.address
 135 #define VALUE_INTERNALVAR(val) (val)->location.internalvar
 136 #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum)
 137 #define VALUE_FRAME(val) ((val)->frame_addr)
 138 #define VALUE_OFFSET(val) (val)->offset
 139 #define VALUE_BITSIZE(val) (val)->bitsize
 140 #define VALUE_BITPOS(val) (val)->bitpos
 141 #define VALUE_NEXT(val) (val)->next
 142 #define VALUE_REGNO(val) (val)->regno
 143 #define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out)
 144
 145 /* Convert a REF to the object referenced. */
 146
 147 #define COERCE_REF(arg)    \
 148 do { CHECK_TYPEDEF (VALUE_TYPE (arg));                                  \
 149      if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_REF)                 \
 150      arg = value_at_lazy (TYPE_TARGET_TYPE (VALUE_TYPE (arg)),          \
 151                           unpack_long (VALUE_TYPE (arg),                \
 152                                        VALUE_CONTENTS (arg)));          \
 153 } while (0)
 154
 155 /* If ARG is an array, convert it to a pointer.
 156    If ARG is an enum, convert it to an integer.
 157    If ARG is a function, convert it to a function pointer.
 158
 159    References are dereferenced.  */
 160
 161 #define COERCE_ARRAY(arg)    \
 162 do { COERCE_REF(arg);                                                   \
 163   if (current_language->c_style_arrays                                  \
 164       && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY)               \
 165     arg = value_coerce_array (arg);                                     \
 166   if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC)                   \
 167     arg = value_coerce_function (arg);                                  \
 168 } while (0)
 169
 170 #define COERCE_NUMBER(arg)  \
 171   do { COERCE_ARRAY(arg);  COERCE_ENUM(arg); } while (0)
 172
 173 #define COERCE_VARYING_ARRAY(arg, real_arg_type)        \
 174 { if (chill_varying_type (real_arg_type))  \
 175     arg = varying_to_slice (arg), real_arg_type = VALUE_TYPE (arg); }
 176
 177 /* If ARG is an enum, convert it to an integer.  */
 178
 179 #define COERCE_ENUM(arg)   { \
 180   if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ENUM)                   \
 181     arg = value_cast (builtin_type_unsigned_int, arg);                  \
 182 }
 183
 184 /* Internal variables (variables for convenience of use of debugger)
 185    are recorded as a chain of these structures.  */
 186
 187 struct internalvar
 188 {
 189   struct internalvar *next;
 190   char *name;
 191   value_ptr value;
 192 };
 193
 194 /* Pointer to member function.  Depends on compiler implementation. */
 195
 196 #define METHOD_PTR_IS_VIRTUAL(ADDR)  ((ADDR) & 0x80000000)
 197 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
 198 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
 199
 200 \f
 201 #include "symtab.h"
 202 #include "gdbtypes.h"
 203 #include "expression.h"
 204
 205 #ifdef __STDC__
 206 struct frame_info;
 207 struct fn_field;
 208 #endif
 209
 210 extern void
 211 print_address_demangle PARAMS ((CORE_ADDR, GDB_FILE *, int));
 212
 213 extern LONGEST value_as_long PARAMS ((value_ptr val));
 214
 215 extern DOUBLEST value_as_double PARAMS ((value_ptr val));
 216
 217 extern CORE_ADDR value_as_pointer PARAMS ((value_ptr val));
 218
 219 extern LONGEST unpack_long PARAMS ((struct type *type, char *valaddr));
 220
 221 extern DOUBLEST unpack_double PARAMS ((struct type *type, char *valaddr,
 222                                        int *invp));
 223
 224 extern CORE_ADDR unpack_pointer PARAMS ((struct type *type, char *valaddr));
 225
 226 extern LONGEST unpack_field_as_long PARAMS ((struct type *type, char *valaddr,
 227                                              int fieldno));
 228
 229 extern value_ptr value_from_longest PARAMS ((struct type *type, LONGEST num));
 230
 231 extern value_ptr value_from_double PARAMS ((struct type *type, DOUBLEST num));
 232
 233 extern value_ptr value_at PARAMS ((struct type *type, CORE_ADDR addr));
 234
 235 extern value_ptr value_at_lazy PARAMS ((struct type *type, CORE_ADDR addr));
 236
 237 extern value_ptr value_from_register PARAMS ((struct type *type, int regnum,
 238                                           struct frame_info * frame));
 239
 240 extern value_ptr value_of_variable PARAMS ((struct symbol *var,
 241                                             struct block *b));
 242
 243 extern value_ptr value_of_register PARAMS ((int regnum));
 244
 245 extern int symbol_read_needs_frame PARAMS ((struct symbol *));
 246
 247 extern value_ptr read_var_value PARAMS ((struct symbol *var,
 248                                          struct frame_info *frame));
 249
 250 extern value_ptr locate_var_value PARAMS ((struct symbol *var,
 251                                        struct frame_info *frame));
 252
 253 extern value_ptr allocate_value PARAMS ((struct type *type));
 254
 255 extern value_ptr allocate_repeat_value PARAMS ((struct type *type, int count));
 256
 257 extern value_ptr value_mark PARAMS ((void));
 258
 259 extern void value_free_to_mark PARAMS ((value_ptr mark));
 260
 261 extern value_ptr value_string PARAMS ((char *ptr, int len));
 262 extern value_ptr value_bitstring PARAMS ((char *ptr, int len));
 263
 264 extern value_ptr value_array PARAMS ((int lowbound, int highbound,
 265                                       value_ptr *elemvec));
 266
 267 extern value_ptr value_concat PARAMS ((value_ptr arg1, value_ptr arg2));
 268
 269 extern value_ptr value_binop PARAMS ((value_ptr arg1, value_ptr arg2,
 270                                       enum exp_opcode op));
 271
 272 extern value_ptr value_add PARAMS ((value_ptr arg1, value_ptr arg2));
 273
 274 extern value_ptr value_sub PARAMS ((value_ptr arg1, value_ptr arg2));
 275
 276 extern value_ptr value_coerce_array PARAMS ((value_ptr arg1));
 277
 278 extern value_ptr value_coerce_function PARAMS ((value_ptr arg1));
 279
 280 extern value_ptr value_ind PARAMS ((value_ptr arg1));
 281
 282 extern value_ptr value_addr PARAMS ((value_ptr arg1));
 283
 284 extern value_ptr value_assign PARAMS ((value_ptr toval, value_ptr fromval));
 285
 286 extern value_ptr value_neg PARAMS ((value_ptr arg1));
 287
 288 extern value_ptr value_complement PARAMS ((value_ptr arg1));
 289
 290 extern value_ptr value_struct_elt PARAMS ((value_ptr *argp, value_ptr *args,
 291                                            char *name,
 292                                            int *static_memfuncp, char *err));
 293
 294 extern value_ptr value_struct_elt_for_reference PARAMS ((struct type *domain,
 295                                                          int offset,
 296                                                          struct type *curtype,
 297                                                          char *name,
 298                                                          struct type *intype));
 299
 300 extern value_ptr value_field PARAMS ((value_ptr arg1, int fieldno));
 301
 302 extern value_ptr value_primitive_field PARAMS ((value_ptr arg1, int offset,
 303                                                 int fieldno,
 304                                                 struct type *arg_type));
 305
 306 extern value_ptr value_cast PARAMS ((struct type *type, value_ptr arg2));
 307
 308 extern value_ptr value_zero PARAMS ((struct type *type, enum lval_type lv));
 309
 310 extern value_ptr value_repeat PARAMS ((value_ptr arg1, int count));
 311
 312 extern value_ptr value_subscript PARAMS ((value_ptr array, value_ptr idx));
 313
 314 extern value_ptr value_from_vtable_info PARAMS ((value_ptr arg,
 315                                                  struct type *type));
 316
 317 extern value_ptr value_being_returned PARAMS ((struct type *valtype,
 318                                                char retbuf[REGISTER_BYTES],
 319                                                int struct_return));
 320
 321 extern value_ptr value_in PARAMS ((value_ptr element, value_ptr set));
 322
 323 extern int value_bit_index PARAMS ((struct type *type, char *addr, int index));
 324
 325 extern int using_struct_return PARAMS ((value_ptr function, CORE_ADDR funcaddr,
 326                                         struct type *value_type, int gcc_p));
 327
 328 extern void set_return_value PARAMS ((value_ptr val));
 329
 330 extern value_ptr evaluate_expression PARAMS ((struct expression *exp));
 331
 332 extern value_ptr evaluate_type PARAMS ((struct expression *exp));
 333
 334 extern value_ptr evaluate_subexp_with_coercion PARAMS ((struct expression *,
 335                                                         int *, enum noside));
 336
 337 extern value_ptr parse_and_eval PARAMS ((char *exp));
 338
 339 extern value_ptr parse_to_comma_and_eval PARAMS ((char **expp));
 340
 341 extern struct type *parse_and_eval_type PARAMS ((char *p, int length));
 342
 343 extern CORE_ADDR parse_and_eval_address PARAMS ((char *exp));
 344
 345 extern CORE_ADDR parse_and_eval_address_1 PARAMS ((char **expptr));
 346
 347 extern value_ptr access_value_history PARAMS ((int num));
 348
 349 extern value_ptr value_of_internalvar PARAMS ((struct internalvar *var));
 350
 351 extern void set_internalvar PARAMS ((struct internalvar *var, value_ptr val));
 352
 353 extern void set_internalvar_component PARAMS ((struct internalvar *var,
 354                                                int offset,
 355                                                int bitpos, int bitsize,
 356                                                value_ptr newvalue));
 357
 358 extern struct internalvar *lookup_internalvar PARAMS ((char *name));
 359
 360 extern int value_equal PARAMS ((value_ptr arg1, value_ptr arg2));
 361
 362 extern int value_less PARAMS ((value_ptr arg1, value_ptr arg2));
 363
 364 extern int value_logical_not PARAMS ((value_ptr arg1));
 365
 366 /* C++ */
 367
 368 extern value_ptr value_of_this PARAMS ((int complain));
 369
 370 extern value_ptr value_x_binop PARAMS ((value_ptr arg1, value_ptr arg2,
 371                                         enum exp_opcode op,
 372                                         enum exp_opcode otherop,
 373                                         enum noside noside));
 374
 375 extern value_ptr value_x_unop PARAMS ((value_ptr arg1, enum exp_opcode op,
 376                                        enum noside noside));
 377
 378 extern value_ptr value_fn_field PARAMS ((value_ptr *arg1p, struct fn_field *f,
 379                                          int j,
 380                                          struct type* type, int offset));
 381
 382 extern value_ptr value_virtual_fn_field PARAMS ((value_ptr *arg1p,
 383                                                  struct fn_field *f, int j,
 384                                                  struct type *type,
 385                                                  int offset));
 386
 387 extern int binop_user_defined_p PARAMS ((enum exp_opcode op,
 388                                          value_ptr arg1, value_ptr arg2));
 389
 390 extern int unop_user_defined_p PARAMS ((enum exp_opcode op, value_ptr arg1));
 391
 392 extern int destructor_name_p PARAMS ((const char *name,
 393                                       const struct type *type));
 394
 395 #define value_free(val) free ((PTR)val)
 396
 397 extern void free_all_values PARAMS ((void));
 398
 399 extern void release_value PARAMS ((value_ptr val));
 400
 401 extern int record_latest_value PARAMS ((value_ptr val));
 402
 403 extern void registers_changed PARAMS ((void));
 404
 405 extern void read_register_bytes PARAMS ((int regbyte, char *myaddr, int len));
 406
 407 extern void write_register_bytes PARAMS ((int regbyte, char *myaddr, int len));
 408
 409 extern void
 410 read_register_gen PARAMS ((int regno, char *myaddr));
 411
 412 extern CORE_ADDR
 413 read_register PARAMS ((int regno));
 414
 415 extern void
 416 write_register PARAMS ((int regno, LONGEST val));
 417
 418 extern void
 419 supply_register PARAMS ((int regno, char *val));
 420
 421 extern void
 422 get_saved_register PARAMS ((char *raw_buffer, int *optimized,
 423                             CORE_ADDR *addrp, struct frame_info *frame,
 424                             int regnum, enum lval_type *lval));
 425
 426 extern void
 427 modify_field PARAMS ((char *addr, LONGEST fieldval, int bitpos, int bitsize));
 428
 429 extern void
 430 type_print PARAMS ((struct type *type, char *varstring, GDB_FILE *stream,
 431                     int show));
 432
 433 extern char *baseclass_addr PARAMS ((struct type *type, int index,
 434                                      char *valaddr,
 435                                      value_ptr *valuep, int *errp));
 436
 437 extern void
 438 print_longest PARAMS ((GDB_FILE *stream, int format, int use_local,
 439                        LONGEST val));
 440
 441 extern void
 442 print_floating PARAMS ((char *valaddr, struct type *type, GDB_FILE *stream));
 443
 444 extern int value_print PARAMS ((value_ptr val, GDB_FILE *stream, int format,
 445                                 enum val_prettyprint pretty));
 446
 447 extern void
 448 value_print_array_elements PARAMS ((value_ptr val, GDB_FILE* stream,
 449                                     int format, enum val_prettyprint pretty));
 450
 451 extern value_ptr
 452 value_release_to_mark PARAMS ((value_ptr mark));
 453
 454 extern int
 455 val_print PARAMS ((struct type *type, char *valaddr, CORE_ADDR address,
 456                    GDB_FILE *stream, int format, int deref_ref,
 457                    int recurse, enum val_prettyprint pretty));
 458
 459 extern int
 460 val_print_string PARAMS ((CORE_ADDR addr, unsigned int len, GDB_FILE *stream));
 461
 462 extern void
 463 print_variable_value PARAMS ((struct symbol *var, struct frame_info *frame,
 464                               GDB_FILE *stream));
 465
 466 extern int check_field PARAMS ((value_ptr, const char *));
 467
 468 extern void
 469 c_typedef_print PARAMS ((struct type *type, struct symbol *news, GDB_FILE *stream));
 470
 471 extern char *
 472 internalvar_name PARAMS ((struct internalvar *var));
 473
 474 extern void
 475 clear_value_history PARAMS ((void));
 476
 477 extern void
 478 clear_internalvars PARAMS ((void));
 479
 480 /* From values.c */
 481
 482 extern value_ptr value_copy PARAMS ((value_ptr));
 483
 484 extern int baseclass_offset PARAMS ((struct type *, int, char *, CORE_ADDR));
 485
 486 /* From valops.c */
 487
 488 extern value_ptr varying_to_slice PARAMS ((value_ptr));
 489
 490 extern value_ptr value_slice PARAMS ((value_ptr, int, int));
 491
 492 extern value_ptr call_function_by_hand PARAMS ((value_ptr, int, value_ptr *));
 493
 494 extern value_ptr value_literal_complex PARAMS ((value_ptr, value_ptr, struct type*));
 495
 496 extern value_ptr find_function_in_inferior PARAMS ((char *));
 497
 498 extern value_ptr value_allocate_space_in_inferior PARAMS ((int));
 499
 500 #endif  /* !defined (VALUE_H) */