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     /* The BFD section associated with this value.  */
 105     asection *bfd_section;
 106     /* Actual contents of the value.  For use of this value; setting
 107        it uses the stuff above.  Not valid if lazy is nonzero.
 108        Target byte-order.  We force it to be aligned properly for any
 109        possible value.  */
 110     union {
 111       long contents[1];
 112       double force_double_align;
 113       LONGEST force_longlong_align;
 114       char *literal_data;
 115     } aligner;
 116   };
 117
 118 typedef struct value *value_ptr;
 119
 120 #define VALUE_TYPE(val) (val)->type
 121 #define VALUE_LAZY(val) (val)->lazy
 122 /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of
 123    the gdb buffer used to hold a copy of the contents of the lval.
 124    VALUE_CONTENTS is used when the contents of the buffer are needed --
 125    it uses value_fetch_lazy() to load the buffer from the process being
 126    debugged if it hasn't already been loaded.  VALUE_CONTENTS_RAW is
 127    used when data is being stored into the buffer, or when it is
 128    certain that the contents of the buffer are valid.  */
 129 #define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents)
 130 #define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\
 131                              VALUE_CONTENTS_RAW(val))
 132 extern int value_fetch_lazy PARAMS ((value_ptr val));
 133
 134 #define VALUE_LVAL(val) (val)->lval
 135 #define VALUE_ADDRESS(val) (val)->location.address
 136 #define VALUE_INTERNALVAR(val) (val)->location.internalvar
 137 #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum)
 138 #define VALUE_FRAME(val) ((val)->frame_addr)
 139 #define VALUE_OFFSET(val) (val)->offset
 140 #define VALUE_BITSIZE(val) (val)->bitsize
 141 #define VALUE_BITPOS(val) (val)->bitpos
 142 #define VALUE_NEXT(val) (val)->next
 143 #define VALUE_REGNO(val) (val)->regno
 144 #define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out)
 145 #define VALUE_BFD_SECTION(val) ((val)->bfd_section)
 146
 147 /* Convert a REF to the object referenced. */
 148
 149 #define COERCE_REF(arg)    \
 150 do { struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg));\
 151      if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF)               \
 152          arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp),    \
 153                               unpack_long (VALUE_TYPE (arg),            \
 154                                            VALUE_CONTENTS (arg)),       \
 155                               VALUE_BFD_SECTION (arg));                 \
 156     } while (0)
 157
 158 /* If ARG is an array, convert it to a pointer.
 159    If ARG is an enum, convert it to an integer.
 160    If ARG is a function, convert it to a function pointer.
 161
 162    References are dereferenced.  */
 163
 164 #define COERCE_ARRAY(arg)    \
 165 do { COERCE_REF(arg);                                                   \
 166   if (current_language->c_style_arrays                                  \
 167       && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY)               \
 168     arg = value_coerce_array (arg);                                     \
 169   if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC)                   \
 170     arg = value_coerce_function (arg);                                  \
 171 } while (0)
 172
 173 #define COERCE_NUMBER(arg)  \
 174   do { COERCE_ARRAY(arg);  COERCE_ENUM(arg); } while (0)
 175
 176 #define COERCE_VARYING_ARRAY(arg, real_arg_type)        \
 177 { if (chill_varying_type (real_arg_type))  \
 178     arg = varying_to_slice (arg), real_arg_type = VALUE_TYPE (arg); }
 179
 180 /* If ARG is an enum, convert it to an integer.  */
 181
 182 #define COERCE_ENUM(arg)   { \
 183   if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM)   \
 184     arg = value_cast (builtin_type_unsigned_int, arg);                  \
 185 }
 186
 187 /* Internal variables (variables for convenience of use of debugger)
 188    are recorded as a chain of these structures.  */
 189
 190 struct internalvar
 191 {
 192   struct internalvar *next;
 193   char *name;
 194   value_ptr value;
 195 };
 196
 197 /* Pointer to member function.  Depends on compiler implementation. */
 198
 199 #define METHOD_PTR_IS_VIRTUAL(ADDR)  ((ADDR) & 0x80000000)
 200 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
 201 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
 202
 203 \f
 204 #include "symtab.h"
 205 #include "gdbtypes.h"
 206 #include "expression.h"
 207
 208 #ifdef __STDC__
 209 struct frame_info;
 210 struct fn_field;
 211 #endif
 212
 213 extern void
 214 print_address_demangle PARAMS ((CORE_ADDR, GDB_FILE *, int));
 215
 216 extern LONGEST value_as_long PARAMS ((value_ptr val));
 217
 218 extern DOUBLEST value_as_double PARAMS ((value_ptr val));
 219
 220 extern CORE_ADDR value_as_pointer PARAMS ((value_ptr val));
 221
 222 extern LONGEST unpack_long PARAMS ((struct type *type, char *valaddr));
 223
 224 extern DOUBLEST unpack_double PARAMS ((struct type *type, char *valaddr,
 225                                        int *invp));
 226
 227 extern CORE_ADDR unpack_pointer PARAMS ((struct type *type, char *valaddr));
 228
 229 extern LONGEST unpack_field_as_long PARAMS ((struct type *type, char *valaddr,
 230                                              int fieldno));
 231
 232 extern value_ptr value_from_longest PARAMS ((struct type *type, LONGEST num));
 233
 234 extern value_ptr value_from_double PARAMS ((struct type *type, DOUBLEST num));
 235
 236 extern value_ptr value_at PARAMS ((struct type *type, CORE_ADDR addr, asection *sect));
 237
 238 extern value_ptr value_at_lazy PARAMS ((struct type *type, CORE_ADDR addr, asection *sect));
 239
 240 extern value_ptr value_from_register PARAMS ((struct type *type, int regnum,
 241                                           struct frame_info * frame));
 242
 243 extern value_ptr value_of_variable PARAMS ((struct symbol *var,
 244                                             struct block *b));
 245
 246 extern value_ptr value_of_register PARAMS ((int regnum));
 247
 248 extern int symbol_read_needs_frame PARAMS ((struct symbol *));
 249
 250 extern value_ptr read_var_value PARAMS ((struct symbol *var,
 251                                          struct frame_info *frame));
 252
 253 extern value_ptr locate_var_value PARAMS ((struct symbol *var,
 254                                        struct frame_info *frame));
 255
 256 extern value_ptr allocate_value PARAMS ((struct type *type));
 257
 258 extern value_ptr allocate_repeat_value PARAMS ((struct type *type, int count));
 259
 260 extern value_ptr value_mark PARAMS ((void));
 261
 262 extern void value_free_to_mark PARAMS ((value_ptr mark));
 263
 264 extern value_ptr value_string PARAMS ((char *ptr, int len));
 265 extern value_ptr value_bitstring PARAMS ((char *ptr, int len));
 266
 267 extern value_ptr value_array PARAMS ((int lowbound, int highbound,
 268                                       value_ptr *elemvec));
 269
 270 extern value_ptr value_concat PARAMS ((value_ptr arg1, value_ptr arg2));
 271
 272 extern value_ptr value_binop PARAMS ((value_ptr arg1, value_ptr arg2,
 273                                       enum exp_opcode op));
 274
 275 extern value_ptr value_add PARAMS ((value_ptr arg1, value_ptr arg2));
 276
 277 extern value_ptr value_sub PARAMS ((value_ptr arg1, value_ptr arg2));
 278
 279 extern value_ptr value_coerce_array PARAMS ((value_ptr arg1));
 280
 281 extern value_ptr value_coerce_function PARAMS ((value_ptr arg1));
 282
 283 extern value_ptr value_ind PARAMS ((value_ptr arg1));
 284
 285 extern value_ptr value_addr PARAMS ((value_ptr arg1));
 286
 287 extern value_ptr value_assign PARAMS ((value_ptr toval, value_ptr fromval));
 288
 289 extern value_ptr value_neg PARAMS ((value_ptr arg1));
 290
 291 extern value_ptr value_complement PARAMS ((value_ptr arg1));
 292
 293 extern value_ptr value_struct_elt PARAMS ((value_ptr *argp, value_ptr *args,
 294                                            char *name,
 295                                            int *static_memfuncp, char *err));
 296
 297 extern value_ptr value_struct_elt_for_reference PARAMS ((struct type *domain,
 298                                                          int offset,
 299                                                          struct type *curtype,
 300                                                          char *name,
 301                                                          struct type *intype));
 302
 303 extern value_ptr value_static_field PARAMS ((struct type *type, int fieldno));
 304
 305 extern value_ptr value_field PARAMS ((value_ptr arg1, int fieldno));
 306
 307 extern value_ptr value_primitive_field PARAMS ((value_ptr arg1, int offset,
 308                                                 int fieldno,
 309                                                 struct type *arg_type));
 310
 311 extern value_ptr value_cast PARAMS ((struct type *type, value_ptr arg2));
 312
 313 extern value_ptr value_zero PARAMS ((struct type *type, enum lval_type lv));
 314
 315 extern value_ptr value_repeat PARAMS ((value_ptr arg1, int count));
 316
 317 extern value_ptr value_subscript PARAMS ((value_ptr array, value_ptr idx));
 318
 319 extern value_ptr value_from_vtable_info PARAMS ((value_ptr arg,
 320                                                  struct type *type));
 321
 322 extern value_ptr value_being_returned PARAMS ((struct type *valtype,
 323                                                char retbuf[REGISTER_BYTES],
 324                                                int struct_return));
 325
 326 extern value_ptr value_in PARAMS ((value_ptr element, value_ptr set));
 327
 328 extern int value_bit_index PARAMS ((struct type *type, char *addr, int index));
 329
 330 extern int using_struct_return PARAMS ((value_ptr function, CORE_ADDR funcaddr,
 331                                         struct type *value_type, int gcc_p));
 332
 333 extern void set_return_value PARAMS ((value_ptr val));
 334
 335 extern value_ptr evaluate_expression PARAMS ((struct expression *exp));
 336
 337 extern value_ptr evaluate_type PARAMS ((struct expression *exp));
 338
 339 extern value_ptr evaluate_subexp_with_coercion PARAMS ((struct expression *,
 340                                                         int *, enum noside));
 341
 342 extern value_ptr parse_and_eval PARAMS ((char *exp));
 343
 344 extern value_ptr parse_to_comma_and_eval PARAMS ((char **expp));
 345
 346 extern struct type *parse_and_eval_type PARAMS ((char *p, int length));
 347
 348 extern CORE_ADDR parse_and_eval_address PARAMS ((char *exp));
 349
 350 extern CORE_ADDR parse_and_eval_address_1 PARAMS ((char **expptr));
 351
 352 extern value_ptr access_value_history PARAMS ((int num));
 353
 354 extern value_ptr value_of_internalvar PARAMS ((struct internalvar *var));
 355
 356 extern void set_internalvar PARAMS ((struct internalvar *var, value_ptr val));
 357
 358 extern void set_internalvar_component PARAMS ((struct internalvar *var,
 359                                                int offset,
 360                                                int bitpos, int bitsize,
 361                                                value_ptr newvalue));
 362
 363 extern struct internalvar *lookup_internalvar PARAMS ((char *name));
 364
 365 extern int value_equal PARAMS ((value_ptr arg1, value_ptr arg2));
 366
 367 extern int value_less PARAMS ((value_ptr arg1, value_ptr arg2));
 368
 369 extern int value_logical_not PARAMS ((value_ptr arg1));
 370
 371 /* C++ */
 372
 373 extern value_ptr value_of_this PARAMS ((int complain));
 374
 375 extern value_ptr value_x_binop PARAMS ((value_ptr arg1, value_ptr arg2,
 376                                         enum exp_opcode op,
 377                                         enum exp_opcode otherop,
 378                                         enum noside noside));
 379
 380 extern value_ptr value_x_unop PARAMS ((value_ptr arg1, enum exp_opcode op,
 381                                        enum noside noside));
 382
 383 extern value_ptr value_fn_field PARAMS ((value_ptr *arg1p, struct fn_field *f,
 384                                          int j,
 385                                          struct type* type, int offset));
 386
 387 extern value_ptr value_virtual_fn_field PARAMS ((value_ptr *arg1p,
 388                                                  struct fn_field *f, int j,
 389                                                  struct type *type,
 390                                                  int offset));
 391
 392 extern int binop_user_defined_p PARAMS ((enum exp_opcode op,
 393                                          value_ptr arg1, value_ptr arg2));
 394
 395 extern int unop_user_defined_p PARAMS ((enum exp_opcode op, value_ptr arg1));
 396
 397 extern int destructor_name_p PARAMS ((const char *name,
 398                                       const struct type *type));
 399
 400 #define value_free(val) free ((PTR)val)
 401
 402 extern void free_all_values PARAMS ((void));
 403
 404 extern void release_value PARAMS ((value_ptr val));
 405
 406 extern int record_latest_value PARAMS ((value_ptr val));
 407
 408 extern void registers_changed PARAMS ((void));
 409
 410 extern void read_register_bytes PARAMS ((int regbyte, char *myaddr, int len));
 411
 412 extern void write_register_bytes PARAMS ((int regbyte, char *myaddr, int len));
 413
 414 extern void
 415 read_register_gen PARAMS ((int regno, char *myaddr));
 416
 417 extern CORE_ADDR
 418 read_register PARAMS ((int regno));
 419
 420 extern CORE_ADDR
 421 read_register_pid PARAMS ((int regno, int pid));
 422
 423 extern void
 424 write_register PARAMS ((int regno, LONGEST val));
 425
 426 extern void
 427 write_register_pid PARAMS ((int regno, LONGEST val, int pid));
 428
 429 extern void
 430 supply_register PARAMS ((int regno, char *val));
 431
 432 extern void
 433 get_saved_register PARAMS ((char *raw_buffer, int *optimized,
 434                             CORE_ADDR *addrp, struct frame_info *frame,
 435                             int regnum, enum lval_type *lval));
 436
 437 extern void
 438 modify_field PARAMS ((char *addr, LONGEST fieldval, int bitpos, int bitsize));
 439
 440 extern void
 441 type_print PARAMS ((struct type *type, char *varstring, GDB_FILE *stream,
 442                     int show));
 443
 444 extern char *baseclass_addr PARAMS ((struct type *type, int index,
 445                                      char *valaddr,
 446                                      value_ptr *valuep, int *errp));
 447
 448 extern void
 449 print_longest PARAMS ((GDB_FILE *stream, int format, int use_local,
 450                        LONGEST val));
 451
 452 extern void
 453 print_floating PARAMS ((char *valaddr, struct type *type, GDB_FILE *stream));
 454
 455 extern int value_print PARAMS ((value_ptr val, GDB_FILE *stream, int format,
 456                                 enum val_prettyprint pretty));
 457
 458 extern void
 459 value_print_array_elements PARAMS ((value_ptr val, GDB_FILE* stream,
 460                                     int format, enum val_prettyprint pretty));
 461
 462 extern value_ptr
 463 value_release_to_mark PARAMS ((value_ptr mark));
 464
 465 extern int
 466 val_print PARAMS ((struct type *type, char *valaddr, CORE_ADDR address,
 467                    GDB_FILE *stream, int format, int deref_ref,
 468                    int recurse, enum val_prettyprint pretty));
 469
 470 extern int
 471 val_print_string PARAMS ((CORE_ADDR addr, int len, int width, GDB_FILE *stream));
 472
 473 extern void
 474 print_variable_value PARAMS ((struct symbol *var, struct frame_info *frame,
 475                               GDB_FILE *stream));
 476
 477 extern int check_field PARAMS ((value_ptr, const char *));
 478
 479 extern void
 480 c_typedef_print PARAMS ((struct type *type, struct symbol *news, GDB_FILE *stream));
 481
 482 extern char *
 483 internalvar_name PARAMS ((struct internalvar *var));
 484
 485 extern void
 486 clear_value_history PARAMS ((void));
 487
 488 extern void
 489 clear_internalvars PARAMS ((void));
 490
 491 /* From values.c */
 492
 493 extern value_ptr value_copy PARAMS ((value_ptr));
 494
 495 extern int baseclass_offset PARAMS ((struct type *, int, char *, CORE_ADDR));
 496
 497 /* From valops.c */
 498
 499 extern value_ptr varying_to_slice PARAMS ((value_ptr));
 500
 501 extern value_ptr value_slice PARAMS ((value_ptr, int, int));
 502
 503 extern value_ptr call_function_by_hand PARAMS ((value_ptr, int, value_ptr *));
 504
 505 extern value_ptr value_literal_complex PARAMS ((value_ptr, value_ptr, struct type*));
 506
 507 extern value_ptr find_function_in_inferior PARAMS ((char *));
 508
 509 extern value_ptr value_allocate_space_in_inferior PARAMS ((int));
 510
 511 extern void _initialize_values PARAMS ((void));
 512
 513 #endif  /* !defined (VALUE_H) */