gdb/value.h

   1 /* Definitions for values of C expressions, for GDB.
   2    Copyright 1986, 1987, 1989, 1992, 1993, 1994 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #if !defined (VALUE_H)
  21 #define VALUE_H 1
  22
  23 /*
  24  * The structure which defines the type of a value.  It should never
  25  * be possible for a program lval value to survive over a call to the inferior
  26  * (ie to be put into the history list or an internal variable).
  27  */
  28 enum lval_type {
  29   /* Not an lval.  */
  30   not_lval,
  31   /* In memory.  Could be a saved register.  */
  32   lval_memory,
  33   /* In a register.  */
  34   lval_register,
  35   /* In a gdb internal variable.  */
  36   lval_internalvar,
  37   /* Part of a gdb internal variable (structure field).  */
  38   lval_internalvar_component,
  39   /* In a register series in a frame not the current one, which may have been
  40      partially saved or saved in different places (otherwise would be
  41      lval_register or lval_memory).  */
  42   lval_reg_frame_relative
  43 };
  44
  45 struct value
  46   {
  47     /* Type of value; either not an lval, or one of the various
  48        different possible kinds of lval.  */
  49     enum lval_type lval;
  50     /* Is it modifiable?  Only relevant if lval != not_lval.  */
  51     int modifiable;
  52     /* Location of value (if lval).  */
  53     union
  54       {
  55         /* Address in inferior or byte of registers structure.  */
  56         CORE_ADDR address;
  57         /* Pointer to internal variable.  */
  58         struct internalvar *internalvar;
  59         /* Number of register.  Only used with
  60            lval_reg_frame_relative.  */
  61         int regnum;
  62       } location;
  63     /* Describes offset of a value within lval a structure in bytes.  */
  64     int offset;
  65     /* Only used for bitfields; number of bits contained in them.  */
  66     int bitsize;
  67     /* Only used for bitfields; position of start of field.
  68        For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB.
  69        For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */
  70     int bitpos;
  71     /* Frame value is relative to.  In practice, this address is only
  72        used if the value is stored in several registers in other than
  73        the current frame, and these registers have not all been saved
  74        at the same place in memory.  This will be described in the
  75        lval enum above as "lval_reg_frame_relative".  */
  76     CORE_ADDR frame_addr;
  77     /* Type of the value.  */
  78     struct type *type;
  79     /* Values are stored in a chain, so that they can be deleted
  80        easily over calls to the inferior.  Values assigned to internal
  81        variables or put into the value history are taken off this
  82        list.  */
  83     struct value *next;
  84     /* If an lval is forced to repeat, a new value is created with
  85        these fields set.  The new value is not an lval.  */
  86     short repeated;
  87     short repetitions;
  88     /* Register number if the value is from a register.  Is not kept
  89        if you take a field of a structure that is stored in a
  90        register.  Shouldn't it be?  */
  91     short regno;
  92     /* If zero, contents of this value are in the contents field.
  93        If nonzero, contents are in inferior memory at address
  94        in the location.address field plus the offset field
  95        (and the lval field should be lval_memory).  */
  96     char lazy;
  97     /* If nonzero, this is the value of a variable which does not
  98        actually exist in the program.  */
  99     char optimized_out;
 100     /* Actual contents of the value.  For use of this value; setting
 101        it uses the stuff above.  Not valid if lazy is nonzero.
 102        Target byte-order.  We force it to be aligned properly for any
 103        possible value.  */
 104     union {
 105       long contents[1];
 106       double force_double_align;
 107       LONGEST force_longlong_align;
 108     } aligner;
 109
 110   };
 111
 112 typedef struct value *value_ptr;
 113
 114 #define VALUE_TYPE(val) (val)->type
 115 #define VALUE_LAZY(val) (val)->lazy
 116 /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of
 117    the gdb buffer used to hold a copy of the contents of the lval.
 118    VALUE_CONTENTS is used when the contents of the buffer are needed --
 119    it uses value_fetch_lazy() to load the buffer from the process being
 120    debugged if it hasn't already been loaded.  VALUE_CONTENTS_RAW is
 121    used when data is being stored into the buffer, or when it is
 122    certain that the contents of the buffer are valid.  */
 123 #define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents)
 124 #define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\
 125                              VALUE_CONTENTS_RAW(val))
 126 extern int value_fetch_lazy PARAMS ((value_ptr val));
 127
 128 #define VALUE_LVAL(val) (val)->lval
 129 #define VALUE_ADDRESS(val) (val)->location.address
 130 #define VALUE_INTERNALVAR(val) (val)->location.internalvar
 131 #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum)
 132 #define VALUE_FRAME(val) ((val)->frame_addr)
 133 #define VALUE_OFFSET(val) (val)->offset
 134 #define VALUE_BITSIZE(val) (val)->bitsize
 135 #define VALUE_BITPOS(val) (val)->bitpos
 136 #define VALUE_NEXT(val) (val)->next
 137 #define VALUE_REPEATED(val) (val)->repeated
 138 #define VALUE_REPETITIONS(val) (val)->repetitions
 139 #define VALUE_REGNO(val) (val)->regno
 140 #define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out)
 141
 142 /* Convert a REF to the object referenced. */
 143
 144 #define COERCE_REF(arg)    \
 145 { if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_REF)                    \
 146     arg = value_at_lazy (TYPE_TARGET_TYPE (VALUE_TYPE (arg)),           \
 147                          unpack_long (VALUE_TYPE (arg),                 \
 148                                       VALUE_CONTENTS (arg)));}
 149
 150 /* If ARG is an array, convert it to a pointer.
 151    If ARG is an enum, convert it to an integer.
 152    If ARG is a function, convert it to a function pointer.
 153
 154    References are dereferenced.  */
 155
 156 #define COERCE_ARRAY(arg)    \
 157 { COERCE_REF(arg);                                                      \
 158   if (VALUE_REPEATED (arg)                                              \
 159       || TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY)               \
 160     arg = value_coerce_array (arg);                                     \
 161   if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC)                   \
 162     arg = value_coerce_function (arg);                                  \
 163   if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ENUM)                   \
 164     arg = value_cast (builtin_type_unsigned_int, arg);                  \
 165 }
 166
 167 /* If ARG is an enum, convert it to an integer.  */
 168
 169 #define COERCE_ENUM(arg)    \
 170 { COERCE_REF (arg); \
 171   if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ENUM)                   \
 172     arg = value_cast (builtin_type_unsigned_int, arg);                  \
 173 }
 174
 175 /* Internal variables (variables for convenience of use of debugger)
 176    are recorded as a chain of these structures.  */
 177
 178 struct internalvar
 179 {
 180   struct internalvar *next;
 181   char *name;
 182   value_ptr value;
 183 };
 184
 185 /* Pointer to member function.  Depends on compiler implementation. */
 186
 187 #define METHOD_PTR_IS_VIRTUAL(ADDR)  ((ADDR) & 0x80000000)
 188 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
 189 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
 190
 191 \f
 192 #include "symtab.h"
 193 #include "gdbtypes.h"
 194 #include "expression.h"
 195
 196 #ifdef __STDC__
 197 struct frame_info;
 198 struct fn_field;
 199 #endif
 200
 201 extern void
 202 print_address_demangle PARAMS ((CORE_ADDR, GDB_FILE *, int));
 203
 204 extern LONGEST value_as_long PARAMS ((value_ptr val));
 205
 206 extern double value_as_double PARAMS ((value_ptr val));
 207
 208 extern CORE_ADDR value_as_pointer PARAMS ((value_ptr val));
 209
 210 extern LONGEST unpack_long PARAMS ((struct type *type, char *valaddr));
 211
 212 extern double unpack_double PARAMS ((struct type *type, char *valaddr,
 213                                      int *invp));
 214
 215 extern CORE_ADDR unpack_pointer PARAMS ((struct type *type, char *valaddr));
 216
 217 extern LONGEST unpack_field_as_long PARAMS ((struct type *type, char *valaddr,
 218                                              int fieldno));
 219
 220 extern value_ptr value_from_longest PARAMS ((struct type *type, LONGEST num));
 221
 222 extern value_ptr value_from_double PARAMS ((struct type *type, double num));
 223
 224 extern value_ptr value_at PARAMS ((struct type *type, CORE_ADDR addr));
 225
 226 extern value_ptr value_at_lazy PARAMS ((struct type *type, CORE_ADDR addr));
 227
 228 /* FIXME:  Assumes equivalence of "struct frame_info *" and "FRAME" */
 229 extern value_ptr value_from_register PARAMS ((struct type *type, int regnum,
 230                                           struct frame_info * frame));
 231
 232 extern value_ptr value_of_variable PARAMS ((struct symbol *var,
 233                                             struct block *b));
 234
 235 extern value_ptr value_of_register PARAMS ((int regnum));
 236
 237 extern int symbol_read_needs_frame PARAMS ((struct symbol *));
 238
 239 /* FIXME:  Assumes equivalence of "struct frame_info *" and "FRAME" */
 240 extern value_ptr read_var_value PARAMS ((struct symbol *var,
 241                                          struct frame_info *frame));
 242
 243 /* FIXME:  Assumes equivalence of "struct frame_info *" and "FRAME" */
 244 extern value_ptr locate_var_value PARAMS ((struct symbol *var,
 245                                        struct frame_info *frame));
 246
 247 extern value_ptr allocate_value PARAMS ((struct type *type));
 248
 249 extern value_ptr allocate_repeat_value PARAMS ((struct type *type, int count));
 250
 251 extern value_ptr value_mark PARAMS ((void));
 252
 253 extern void value_free_to_mark PARAMS ((value_ptr mark));
 254
 255 extern value_ptr value_string PARAMS ((char *ptr, int len));
 256
 257 extern value_ptr value_array PARAMS ((int lowbound, int highbound,
 258                                       value_ptr *elemvec));
 259
 260 extern value_ptr value_concat PARAMS ((value_ptr arg1, value_ptr arg2));
 261
 262 extern value_ptr value_binop PARAMS ((value_ptr arg1, value_ptr arg2,
 263                                       enum exp_opcode op));
 264
 265 extern value_ptr value_add PARAMS ((value_ptr arg1, value_ptr arg2));
 266
 267 extern value_ptr value_sub PARAMS ((value_ptr arg1, value_ptr arg2));
 268
 269 extern value_ptr value_coerce_array PARAMS ((value_ptr arg1));
 270
 271 extern value_ptr value_coerce_function PARAMS ((value_ptr arg1));
 272
 273 extern value_ptr value_ind PARAMS ((value_ptr arg1));
 274
 275 extern value_ptr value_addr PARAMS ((value_ptr arg1));
 276
 277 extern value_ptr value_assign PARAMS ((value_ptr toval, value_ptr fromval));
 278
 279 extern value_ptr value_neg PARAMS ((value_ptr arg1));
 280
 281 extern value_ptr value_complement PARAMS ((value_ptr arg1));
 282
 283 extern value_ptr value_struct_elt PARAMS ((value_ptr *argp, value_ptr *args,
 284                                            char *name,
 285                                            int *static_memfuncp, char *err));
 286
 287 extern value_ptr value_struct_elt_for_reference PARAMS ((struct type *domain,
 288                                                          int offset,
 289                                                          struct type *curtype,
 290                                                          char *name,
 291                                                          struct type *intype));
 292
 293 extern value_ptr value_field PARAMS ((value_ptr arg1, int fieldno));
 294
 295 extern value_ptr value_primitive_field PARAMS ((value_ptr arg1, int offset,
 296                                                 int fieldno,
 297                                                 struct type *arg_type));
 298
 299 extern value_ptr value_cast PARAMS ((struct type *type, value_ptr arg2));
 300
 301 extern value_ptr value_zero PARAMS ((struct type *type, enum lval_type lv));
 302
 303 extern value_ptr value_repeat PARAMS ((value_ptr arg1, int count));
 304
 305 extern value_ptr value_subscript PARAMS ((value_ptr array, value_ptr idx));
 306
 307 extern value_ptr value_from_vtable_info PARAMS ((value_ptr arg,
 308                                                  struct type *type));
 309
 310 extern value_ptr value_being_returned PARAMS ((struct type *valtype,
 311                                                char retbuf[REGISTER_BYTES],
 312                                                int struct_return));
 313
 314 extern value_ptr value_in PARAMS ((value_ptr element, value_ptr set));
 315
 316 extern int value_bit_index PARAMS ((struct type *type, char *addr, int index));
 317
 318 extern int using_struct_return PARAMS ((value_ptr function, CORE_ADDR funcaddr,
 319                                         struct type *value_type, int gcc_p));
 320
 321 extern void set_return_value PARAMS ((value_ptr val));
 322
 323 extern value_ptr evaluate_expression PARAMS ((struct expression *exp));
 324
 325 extern value_ptr evaluate_type PARAMS ((struct expression *exp));
 326
 327 extern value_ptr parse_and_eval PARAMS ((char *exp));
 328
 329 extern value_ptr parse_to_comma_and_eval PARAMS ((char **expp));
 330
 331 extern struct type *parse_and_eval_type PARAMS ((char *p, int length));
 332
 333 extern CORE_ADDR parse_and_eval_address PARAMS ((char *exp));
 334
 335 extern CORE_ADDR parse_and_eval_address_1 PARAMS ((char **expptr));
 336
 337 extern value_ptr access_value_history PARAMS ((int num));
 338
 339 extern value_ptr value_of_internalvar PARAMS ((struct internalvar *var));
 340
 341 extern void set_internalvar PARAMS ((struct internalvar *var, value_ptr val));
 342
 343 extern void set_internalvar_component PARAMS ((struct internalvar *var,
 344                                                int offset,
 345                                                int bitpos, int bitsize,
 346                                                value_ptr newvalue));
 347
 348 extern struct internalvar *lookup_internalvar PARAMS ((char *name));
 349
 350 extern int value_equal PARAMS ((value_ptr arg1, value_ptr arg2));
 351
 352 extern int value_less PARAMS ((value_ptr arg1, value_ptr arg2));
 353
 354 extern int value_logical_not PARAMS ((value_ptr arg1));
 355
 356 /* C++ */
 357
 358 extern value_ptr value_of_this PARAMS ((int complain));
 359
 360 extern value_ptr value_x_binop PARAMS ((value_ptr arg1, value_ptr arg2,
 361                                         enum exp_opcode op,
 362                                         enum exp_opcode otherop));
 363
 364 extern value_ptr value_x_unop PARAMS ((value_ptr arg1, enum exp_opcode op));
 365
 366 extern value_ptr value_fn_field PARAMS ((value_ptr *arg1p, struct fn_field *f,
 367                                          int j,
 368                                          struct type* type, int offset));
 369
 370 extern value_ptr value_virtual_fn_field PARAMS ((value_ptr *arg1p,
 371                                                  struct fn_field *f, int j,
 372                                                  struct type *type,
 373                                                  int offset));
 374
 375 extern int binop_user_defined_p PARAMS ((enum exp_opcode op,
 376                                          value_ptr arg1, value_ptr arg2));
 377
 378 extern int unop_user_defined_p PARAMS ((enum exp_opcode op, value_ptr arg1));
 379
 380 extern int destructor_name_p PARAMS ((const char *name,
 381                                       const struct type *type));
 382
 383 #define value_free(val) free ((PTR)val)
 384
 385 extern void free_all_values PARAMS ((void));
 386
 387 extern void release_value PARAMS ((value_ptr val));
 388
 389 extern int record_latest_value PARAMS ((value_ptr val));
 390
 391 extern void registers_changed PARAMS ((void));
 392
 393 extern void read_register_bytes PARAMS ((int regbyte, char *myaddr, int len));
 394
 395 extern void write_register_bytes PARAMS ((int regbyte, char *myaddr, int len));
 396
 397 extern void
 398 read_register_gen PARAMS ((int regno, char *myaddr));
 399
 400 extern CORE_ADDR
 401 read_register PARAMS ((int regno));
 402
 403 extern void
 404 write_register PARAMS ((int regno, LONGEST val));
 405
 406 extern void
 407 supply_register PARAMS ((int regno, char *val));
 408
 409 /* FIXME:  Assumes equivalence of "struct frame_info *" and "FRAME" */
 410 extern void
 411 get_saved_register PARAMS ((char *raw_buffer, int *optimized,
 412                             CORE_ADDR *addrp, struct frame_info *frame,
 413                             int regnum, enum lval_type *lval));
 414
 415 extern void
 416 modify_field PARAMS ((char *addr, LONGEST fieldval, int bitpos, int bitsize));
 417
 418 extern void
 419 type_print PARAMS ((struct type *type, char *varstring, GDB_FILE *stream,
 420                     int show));
 421
 422 extern char *baseclass_addr PARAMS ((struct type *type, int index,
 423                                      char *valaddr,
 424                                      value_ptr *valuep, int *errp));
 425
 426 extern void
 427 print_longest PARAMS ((GDB_FILE *stream, int format, int use_local,
 428                        LONGEST val));
 429
 430 extern void
 431 print_floating PARAMS ((char *valaddr, struct type *type, GDB_FILE *stream));
 432
 433 extern int value_print PARAMS ((value_ptr val, GDB_FILE *stream, int format,
 434                                 enum val_prettyprint pretty));
 435
 436 extern value_ptr
 437 value_release_to_mark PARAMS ((value_ptr mark));
 438
 439 extern int
 440 val_print PARAMS ((struct type *type, char *valaddr, CORE_ADDR address,
 441                    GDB_FILE *stream, int format, int deref_ref,
 442                    int recurse, enum val_prettyprint pretty));
 443
 444 extern int
 445 val_print_string PARAMS ((CORE_ADDR addr, unsigned int len, GDB_FILE *stream));
 446
 447 /* FIXME:  Assumes equivalence of "struct frame_info *" and "FRAME" */
 448 extern void
 449 print_variable_value PARAMS ((struct symbol *var, struct frame_info *frame,
 450                               GDB_FILE *stream));
 451
 452 extern value_ptr value_arg_coerce PARAMS ((value_ptr));
 453
 454 extern int check_field PARAMS ((value_ptr, const char *));
 455
 456 extern void
 457 c_typedef_print PARAMS ((struct type *type, struct symbol *new, GDB_FILE *stream));
 458
 459 extern char *
 460 internalvar_name PARAMS ((struct internalvar *var));
 461
 462 extern void
 463 clear_value_history PARAMS ((void));
 464
 465 extern void
 466 clear_internalvars PARAMS ((void));
 467
 468 /* From values.c */
 469
 470 extern value_ptr value_copy PARAMS ((value_ptr));
 471
 472 extern int baseclass_offset PARAMS ((struct type *, int, value_ptr, int));
 473
 474 /* From valops.c */
 475
 476 extern value_ptr call_function_by_hand PARAMS ((value_ptr, int, value_ptr *));
 477
 478 #endif  /* !defined (VALUE_H) */