| File: | src/gnu/usr.bin/binutils/gdb/values.c |
| Warning: | line 1196, column 7 Value stored to 'len' during its initialization is never read |
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| 1 | /* Low level packing and unpacking of values for GDB, the GNU Debugger. |
| 2 | |
| 3 | Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, |
| 4 | 1995, 1996, 1997, 1998, 1999, 2000, 2002, 2003 Free Software |
| 5 | 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 2 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, write to the Free Software |
| 21 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 22 | Boston, MA 02111-1307, USA. */ |
| 23 | |
| 24 | #include "defs.h" |
| 25 | #include "gdb_string.h" |
| 26 | #include "symtab.h" |
| 27 | #include "gdbtypes.h" |
| 28 | #include "value.h" |
| 29 | #include "gdbcore.h" |
| 30 | #include "command.h" |
| 31 | #include "gdbcmd.h" |
| 32 | #include "target.h" |
| 33 | #include "language.h" |
| 34 | #include "scm-lang.h" |
| 35 | #include "demangle.h" |
| 36 | #include "doublest.h" |
| 37 | #include "gdb_assert.h" |
| 38 | #include "regcache.h" |
| 39 | #include "block.h" |
| 40 | |
| 41 | /* Prototypes for exported functions. */ |
| 42 | |
| 43 | void _initialize_values (void); |
| 44 | |
| 45 | /* Prototypes for local functions. */ |
| 46 | |
| 47 | static void show_values (char *, int); |
| 48 | |
| 49 | static void show_convenience (char *, int); |
| 50 | |
| 51 | |
| 52 | /* The value-history records all the values printed |
| 53 | by print commands during this session. Each chunk |
| 54 | records 60 consecutive values. The first chunk on |
| 55 | the chain records the most recent values. |
| 56 | The total number of values is in value_history_count. */ |
| 57 | |
| 58 | #define VALUE_HISTORY_CHUNK60 60 |
| 59 | |
| 60 | struct value_history_chunk |
| 61 | { |
| 62 | struct value_history_chunk *next; |
| 63 | struct value *values[VALUE_HISTORY_CHUNK60]; |
| 64 | }; |
| 65 | |
| 66 | /* Chain of chunks now in use. */ |
| 67 | |
| 68 | static struct value_history_chunk *value_history_chain; |
| 69 | |
| 70 | static int value_history_count; /* Abs number of last entry stored */ |
| 71 | |
| 72 | /* List of all value objects currently allocated |
| 73 | (except for those released by calls to release_value) |
| 74 | This is so they can be freed after each command. */ |
| 75 | |
| 76 | static struct value *all_values; |
| 77 | |
| 78 | /* Allocate a value that has the correct length for type TYPE. */ |
| 79 | |
| 80 | struct value * |
| 81 | allocate_value (struct type *type) |
| 82 | { |
| 83 | struct value *val; |
| 84 | struct type *atype = check_typedef (type); |
| 85 | |
| 86 | val = (struct value *) xmalloc (sizeof (struct value) + TYPE_LENGTH (atype)(atype)->length); |
| 87 | VALUE_NEXT (val)(val)->next = all_values; |
| 88 | all_values = val; |
| 89 | VALUE_TYPE (val)(val)->type = type; |
| 90 | VALUE_ENCLOSING_TYPE (val)(val)->enclosing_type = type; |
| 91 | VALUE_LVAL (val)(val)->lval = not_lval; |
| 92 | VALUE_ADDRESS (val)(val)->location.address = 0; |
| 93 | VALUE_FRAME_ID (val)((val)->frame_id) = null_frame_id; |
| 94 | VALUE_OFFSET (val)(val)->offset = 0; |
| 95 | VALUE_BITPOS (val)(val)->bitpos = 0; |
| 96 | VALUE_BITSIZE (val)(val)->bitsize = 0; |
| 97 | VALUE_REGNO (val)(val)->regno = -1; |
| 98 | VALUE_LAZY (val)(val)->lazy = 0; |
| 99 | VALUE_OPTIMIZED_OUT (val)((val)->optimized_out) = 0; |
| 100 | VALUE_BFD_SECTION (val)((val)->bfd_section) = NULL((void*)0); |
| 101 | VALUE_EMBEDDED_OFFSET (val)((val)->embedded_offset) = 0; |
| 102 | VALUE_POINTED_TO_OFFSET (val)((val)->pointed_to_offset) = 0; |
| 103 | val->modifiable = 1; |
| 104 | return val; |
| 105 | } |
| 106 | |
| 107 | /* Allocate a value that has the correct length |
| 108 | for COUNT repetitions type TYPE. */ |
| 109 | |
| 110 | struct value * |
| 111 | allocate_repeat_value (struct type *type, int count) |
| 112 | { |
| 113 | int low_bound = current_language->string_lower_bound; /* ??? */ |
| 114 | /* FIXME-type-allocation: need a way to free this type when we are |
| 115 | done with it. */ |
| 116 | struct type *range_type |
| 117 | = create_range_type ((struct type *) NULL((void*)0), builtin_type_int, |
| 118 | low_bound, count + low_bound - 1); |
| 119 | /* FIXME-type-allocation: need a way to free this type when we are |
| 120 | done with it. */ |
| 121 | return allocate_value (create_array_type ((struct type *) NULL((void*)0), |
| 122 | type, range_type)); |
| 123 | } |
| 124 | |
| 125 | /* Return a mark in the value chain. All values allocated after the |
| 126 | mark is obtained (except for those released) are subject to being freed |
| 127 | if a subsequent value_free_to_mark is passed the mark. */ |
| 128 | struct value * |
| 129 | value_mark (void) |
| 130 | { |
| 131 | return all_values; |
| 132 | } |
| 133 | |
| 134 | /* Free all values allocated since MARK was obtained by value_mark |
| 135 | (except for those released). */ |
| 136 | void |
| 137 | value_free_to_mark (struct value *mark) |
| 138 | { |
| 139 | struct value *val; |
| 140 | struct value *next; |
| 141 | |
| 142 | for (val = all_values; val && val != mark; val = next) |
| 143 | { |
| 144 | next = VALUE_NEXT (val)(val)->next; |
| 145 | value_free (val)xfree (val); |
| 146 | } |
| 147 | all_values = val; |
| 148 | } |
| 149 | |
| 150 | /* Free all the values that have been allocated (except for those released). |
| 151 | Called after each command, successful or not. */ |
| 152 | |
| 153 | void |
| 154 | free_all_values (void) |
| 155 | { |
| 156 | struct value *val; |
| 157 | struct value *next; |
| 158 | |
| 159 | for (val = all_values; val; val = next) |
| 160 | { |
| 161 | next = VALUE_NEXT (val)(val)->next; |
| 162 | value_free (val)xfree (val); |
| 163 | } |
| 164 | |
| 165 | all_values = 0; |
| 166 | } |
| 167 | |
| 168 | /* Remove VAL from the chain all_values |
| 169 | so it will not be freed automatically. */ |
| 170 | |
| 171 | void |
| 172 | release_value (struct value *val) |
| 173 | { |
| 174 | struct value *v; |
| 175 | |
| 176 | if (all_values == val) |
| 177 | { |
| 178 | all_values = val->next; |
| 179 | return; |
| 180 | } |
| 181 | |
| 182 | for (v = all_values; v; v = v->next) |
| 183 | { |
| 184 | if (v->next == val) |
| 185 | { |
| 186 | v->next = val->next; |
| 187 | break; |
| 188 | } |
| 189 | } |
| 190 | } |
| 191 | |
| 192 | /* Release all values up to mark */ |
| 193 | struct value * |
| 194 | value_release_to_mark (struct value *mark) |
| 195 | { |
| 196 | struct value *val; |
| 197 | struct value *next; |
| 198 | |
| 199 | for (val = next = all_values; next; next = VALUE_NEXT (next)(next)->next) |
| 200 | if (VALUE_NEXT (next)(next)->next == mark) |
| 201 | { |
| 202 | all_values = VALUE_NEXT (next)(next)->next; |
| 203 | VALUE_NEXT (next)(next)->next = 0; |
| 204 | return val; |
| 205 | } |
| 206 | all_values = 0; |
| 207 | return val; |
| 208 | } |
| 209 | |
| 210 | /* Return a copy of the value ARG. |
| 211 | It contains the same contents, for same memory address, |
| 212 | but it's a different block of storage. */ |
| 213 | |
| 214 | struct value * |
| 215 | value_copy (struct value *arg) |
| 216 | { |
| 217 | struct type *encl_type = VALUE_ENCLOSING_TYPE (arg)(arg)->enclosing_type; |
| 218 | struct value *val = allocate_value (encl_type); |
| 219 | VALUE_TYPE (val)(val)->type = VALUE_TYPE (arg)(arg)->type; |
| 220 | VALUE_LVAL (val)(val)->lval = VALUE_LVAL (arg)(arg)->lval; |
| 221 | VALUE_ADDRESS (val)(val)->location.address = VALUE_ADDRESS (arg)(arg)->location.address; |
| 222 | VALUE_OFFSET (val)(val)->offset = VALUE_OFFSET (arg)(arg)->offset; |
| 223 | VALUE_BITPOS (val)(val)->bitpos = VALUE_BITPOS (arg)(arg)->bitpos; |
| 224 | VALUE_BITSIZE (val)(val)->bitsize = VALUE_BITSIZE (arg)(arg)->bitsize; |
| 225 | VALUE_FRAME_ID (val)((val)->frame_id) = VALUE_FRAME_ID (arg)((arg)->frame_id); |
| 226 | VALUE_REGNO (val)(val)->regno = VALUE_REGNO (arg)(arg)->regno; |
| 227 | VALUE_LAZY (val)(val)->lazy = VALUE_LAZY (arg)(arg)->lazy; |
| 228 | VALUE_OPTIMIZED_OUT (val)((val)->optimized_out) = VALUE_OPTIMIZED_OUT (arg)((arg)->optimized_out); |
| 229 | VALUE_EMBEDDED_OFFSET (val)((val)->embedded_offset) = VALUE_EMBEDDED_OFFSET (arg)((arg)->embedded_offset); |
| 230 | VALUE_POINTED_TO_OFFSET (val)((val)->pointed_to_offset) = VALUE_POINTED_TO_OFFSET (arg)((arg)->pointed_to_offset); |
| 231 | VALUE_BFD_SECTION (val)((val)->bfd_section) = VALUE_BFD_SECTION (arg)((arg)->bfd_section); |
| 232 | val->modifiable = arg->modifiable; |
| 233 | if (!VALUE_LAZY (val)(val)->lazy) |
| 234 | { |
| 235 | memcpy (VALUE_CONTENTS_ALL_RAW (val)((char *) (val)->aligner.contents), VALUE_CONTENTS_ALL_RAW (arg)((char *) (arg)->aligner.contents), |
| 236 | TYPE_LENGTH (VALUE_ENCLOSING_TYPE (arg))((arg)->enclosing_type)->length); |
| 237 | |
| 238 | } |
| 239 | return val; |
| 240 | } |
| 241 | |
| 242 | /* Access to the value history. */ |
| 243 | |
| 244 | /* Record a new value in the value history. |
| 245 | Returns the absolute history index of the entry. |
| 246 | Result of -1 indicates the value was not saved; otherwise it is the |
| 247 | value history index of this new item. */ |
| 248 | |
| 249 | int |
| 250 | record_latest_value (struct value *val) |
| 251 | { |
| 252 | int i; |
| 253 | |
| 254 | /* We don't want this value to have anything to do with the inferior anymore. |
| 255 | In particular, "set $1 = 50" should not affect the variable from which |
| 256 | the value was taken, and fast watchpoints should be able to assume that |
| 257 | a value on the value history never changes. */ |
| 258 | if (VALUE_LAZY (val)(val)->lazy) |
| 259 | value_fetch_lazy (val); |
| 260 | /* We preserve VALUE_LVAL so that the user can find out where it was fetched |
| 261 | from. This is a bit dubious, because then *&$1 does not just return $1 |
| 262 | but the current contents of that location. c'est la vie... */ |
| 263 | val->modifiable = 0; |
| 264 | release_value (val); |
| 265 | |
| 266 | /* Here we treat value_history_count as origin-zero |
| 267 | and applying to the value being stored now. */ |
| 268 | |
| 269 | i = value_history_count % VALUE_HISTORY_CHUNK60; |
| 270 | if (i == 0) |
| 271 | { |
| 272 | struct value_history_chunk *new |
| 273 | = (struct value_history_chunk *) |
| 274 | xmalloc (sizeof (struct value_history_chunk)); |
| 275 | memset (new->values, 0, sizeof new->values); |
| 276 | new->next = value_history_chain; |
| 277 | value_history_chain = new; |
| 278 | } |
| 279 | |
| 280 | value_history_chain->values[i] = val; |
| 281 | |
| 282 | /* Now we regard value_history_count as origin-one |
| 283 | and applying to the value just stored. */ |
| 284 | |
| 285 | return ++value_history_count; |
| 286 | } |
| 287 | |
| 288 | /* Return a copy of the value in the history with sequence number NUM. */ |
| 289 | |
| 290 | struct value * |
| 291 | access_value_history (int num) |
| 292 | { |
| 293 | struct value_history_chunk *chunk; |
| 294 | int i; |
| 295 | int absnum = num; |
| 296 | |
| 297 | if (absnum <= 0) |
| 298 | absnum += value_history_count; |
| 299 | |
| 300 | if (absnum <= 0) |
| 301 | { |
| 302 | if (num == 0) |
| 303 | error ("The history is empty."); |
| 304 | else if (num == 1) |
| 305 | error ("There is only one value in the history."); |
| 306 | else |
| 307 | error ("History does not go back to $$%d.", -num); |
| 308 | } |
| 309 | if (absnum > value_history_count) |
| 310 | error ("History has not yet reached $%d.", absnum); |
| 311 | |
| 312 | absnum--; |
| 313 | |
| 314 | /* Now absnum is always absolute and origin zero. */ |
| 315 | |
| 316 | chunk = value_history_chain; |
| 317 | for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK60 - absnum / VALUE_HISTORY_CHUNK60; |
| 318 | i > 0; i--) |
| 319 | chunk = chunk->next; |
| 320 | |
| 321 | return value_copy (chunk->values[absnum % VALUE_HISTORY_CHUNK60]); |
| 322 | } |
| 323 | |
| 324 | /* Clear the value history entirely. |
| 325 | Must be done when new symbol tables are loaded, |
| 326 | because the type pointers become invalid. */ |
| 327 | |
| 328 | void |
| 329 | clear_value_history (void) |
| 330 | { |
| 331 | struct value_history_chunk *next; |
| 332 | int i; |
| 333 | struct value *val; |
| 334 | |
| 335 | while (value_history_chain) |
| 336 | { |
| 337 | for (i = 0; i < VALUE_HISTORY_CHUNK60; i++) |
| 338 | if ((val = value_history_chain->values[i]) != NULL((void*)0)) |
| 339 | xfree (val); |
| 340 | next = value_history_chain->next; |
| 341 | xfree (value_history_chain); |
| 342 | value_history_chain = next; |
| 343 | } |
| 344 | value_history_count = 0; |
| 345 | } |
| 346 | |
| 347 | static void |
| 348 | show_values (char *num_exp, int from_tty) |
| 349 | { |
| 350 | int i; |
| 351 | struct value *val; |
| 352 | static int num = 1; |
| 353 | |
| 354 | if (num_exp) |
| 355 | { |
| 356 | /* "info history +" should print from the stored position. |
| 357 | "info history <exp>" should print around value number <exp>. */ |
| 358 | if (num_exp[0] != '+' || num_exp[1] != '\0') |
| 359 | num = parse_and_eval_long (num_exp) - 5; |
| 360 | } |
| 361 | else |
| 362 | { |
| 363 | /* "info history" means print the last 10 values. */ |
| 364 | num = value_history_count - 9; |
| 365 | } |
| 366 | |
| 367 | if (num <= 0) |
| 368 | num = 1; |
| 369 | |
| 370 | for (i = num; i < num + 10 && i <= value_history_count; i++) |
| 371 | { |
| 372 | val = access_value_history (i); |
| 373 | printf_filtered ("$%d = ", i); |
| 374 | value_print (val, gdb_stdout, 0, Val_pretty_default); |
| 375 | printf_filtered ("\n"); |
| 376 | } |
| 377 | |
| 378 | /* The next "info history +" should start after what we just printed. */ |
| 379 | num += 10; |
| 380 | |
| 381 | /* Hitting just return after this command should do the same thing as |
| 382 | "info history +". If num_exp is null, this is unnecessary, since |
| 383 | "info history +" is not useful after "info history". */ |
| 384 | if (from_tty && num_exp) |
| 385 | { |
| 386 | num_exp[0] = '+'; |
| 387 | num_exp[1] = '\0'; |
| 388 | } |
| 389 | } |
| 390 | |
| 391 | /* Internal variables. These are variables within the debugger |
| 392 | that hold values assigned by debugger commands. |
| 393 | The user refers to them with a '$' prefix |
| 394 | that does not appear in the variable names stored internally. */ |
| 395 | |
| 396 | static struct internalvar *internalvars; |
| 397 | |
| 398 | /* Look up an internal variable with name NAME. NAME should not |
| 399 | normally include a dollar sign. |
| 400 | |
| 401 | If the specified internal variable does not exist, |
| 402 | one is created, with a void value. */ |
| 403 | |
| 404 | struct internalvar * |
| 405 | lookup_internalvar (char *name) |
| 406 | { |
| 407 | struct internalvar *var; |
| 408 | |
| 409 | for (var = internalvars; var; var = var->next) |
| 410 | if (strcmp (var->name, name) == 0) |
| 411 | return var; |
| 412 | |
| 413 | var = (struct internalvar *) xmalloc (sizeof (struct internalvar)); |
| 414 | var->name = concat (name, NULL((void*)0)); |
| 415 | var->value = allocate_value (builtin_type_void); |
| 416 | release_value (var->value); |
| 417 | var->next = internalvars; |
| 418 | internalvars = var; |
| 419 | return var; |
| 420 | } |
| 421 | |
| 422 | struct value * |
| 423 | value_of_internalvar (struct internalvar *var) |
| 424 | { |
| 425 | struct value *val; |
| 426 | |
| 427 | val = value_copy (var->value); |
| 428 | if (VALUE_LAZY (val)(val)->lazy) |
| 429 | value_fetch_lazy (val); |
| 430 | VALUE_LVAL (val)(val)->lval = lval_internalvar; |
| 431 | VALUE_INTERNALVAR (val)(val)->location.internalvar = var; |
| 432 | return val; |
| 433 | } |
| 434 | |
| 435 | void |
| 436 | set_internalvar_component (struct internalvar *var, int offset, int bitpos, |
| 437 | int bitsize, struct value *newval) |
| 438 | { |
| 439 | char *addr = VALUE_CONTENTS (var->value)((void)((var->value)->lazy && value_fetch_lazy( var->value)), ((char *) (var->value)->aligner.contents + (var->value)->embedded_offset)) + offset; |
| 440 | |
| 441 | if (bitsize) |
| 442 | modify_field (addr, value_as_long (newval), |
| 443 | bitpos, bitsize); |
| 444 | else |
| 445 | memcpy (addr, VALUE_CONTENTS (newval)((void)((newval)->lazy && value_fetch_lazy(newval) ), ((char *) (newval)->aligner.contents + (newval)->embedded_offset )), TYPE_LENGTH (VALUE_TYPE (newval))((newval)->type)->length); |
| 446 | } |
| 447 | |
| 448 | void |
| 449 | set_internalvar (struct internalvar *var, struct value *val) |
| 450 | { |
| 451 | struct value *newval; |
| 452 | |
| 453 | newval = value_copy (val); |
| 454 | newval->modifiable = 1; |
| 455 | |
| 456 | /* Force the value to be fetched from the target now, to avoid problems |
| 457 | later when this internalvar is referenced and the target is gone or |
| 458 | has changed. */ |
| 459 | if (VALUE_LAZY (newval)(newval)->lazy) |
| 460 | value_fetch_lazy (newval); |
| 461 | |
| 462 | /* Begin code which must not call error(). If var->value points to |
| 463 | something free'd, an error() obviously leaves a dangling pointer. |
| 464 | But we also get a danling pointer if var->value points to |
| 465 | something in the value chain (i.e., before release_value is |
| 466 | called), because after the error free_all_values will get called before |
| 467 | long. */ |
| 468 | xfree (var->value); |
| 469 | var->value = newval; |
| 470 | release_value (newval); |
| 471 | /* End code which must not call error(). */ |
| 472 | } |
| 473 | |
| 474 | char * |
| 475 | internalvar_name (struct internalvar *var) |
| 476 | { |
| 477 | return var->name; |
| 478 | } |
| 479 | |
| 480 | /* Free all internalvars. Done when new symtabs are loaded, |
| 481 | because that makes the values invalid. */ |
| 482 | |
| 483 | void |
| 484 | clear_internalvars (void) |
| 485 | { |
| 486 | struct internalvar *var; |
| 487 | |
| 488 | while (internalvars) |
| 489 | { |
| 490 | var = internalvars; |
| 491 | internalvars = var->next; |
| 492 | xfree (var->name); |
| 493 | xfree (var->value); |
| 494 | xfree (var); |
| 495 | } |
| 496 | } |
| 497 | |
| 498 | static void |
| 499 | show_convenience (char *ignore, int from_tty) |
| 500 | { |
| 501 | struct internalvar *var; |
| 502 | int varseen = 0; |
| 503 | |
| 504 | for (var = internalvars; var; var = var->next) |
| 505 | { |
| 506 | if (!varseen) |
| 507 | { |
| 508 | varseen = 1; |
| 509 | } |
| 510 | printf_filtered ("$%s = ", var->name); |
| 511 | value_print (var->value, gdb_stdout, 0, Val_pretty_default); |
| 512 | printf_filtered ("\n"); |
| 513 | } |
| 514 | if (!varseen) |
| 515 | printf_unfiltered ("No debugger convenience variables now defined.\n\ |
| 516 | Convenience variables have names starting with \"$\";\n\ |
| 517 | use \"set\" as in \"set $foo = 5\" to define them.\n"); |
| 518 | } |
| 519 | |
| 520 | /* Extract a value as a C number (either long or double). |
| 521 | Knows how to convert fixed values to double, or |
| 522 | floating values to long. |
| 523 | Does not deallocate the value. */ |
| 524 | |
| 525 | LONGESTlong |
| 526 | value_as_long (struct value *val) |
| 527 | { |
| 528 | /* This coerces arrays and functions, which is necessary (e.g. |
| 529 | in disassemble_command). It also dereferences references, which |
| 530 | I suspect is the most logical thing to do. */ |
| 531 | COERCE_ARRAY (val)do { do { struct type *value_type_arg_tmp = check_typedef ((val )->type); if ((value_type_arg_tmp)->main_type->code == TYPE_CODE_REF) val = value_at_lazy ((value_type_arg_tmp)-> main_type->target_type, unpack_pointer ((val)->type, (( void)((val)->lazy && value_fetch_lazy(val)), ((char *) (val)->aligner.contents + (val)->embedded_offset))) , ((val)->bfd_section)); } while (0); if (current_language ->c_style_arrays && ((val)->type)->main_type ->code == TYPE_CODE_ARRAY) val = value_coerce_array (val); if (((val)->type)->main_type->code == TYPE_CODE_FUNC ) val = value_coerce_function (val); } while (0); |
| 532 | return unpack_long (VALUE_TYPE (val)(val)->type, VALUE_CONTENTS (val)((void)((val)->lazy && value_fetch_lazy(val)), ((char *) (val)->aligner.contents + (val)->embedded_offset))); |
| 533 | } |
| 534 | |
| 535 | DOUBLEST |
| 536 | value_as_double (struct value *val) |
| 537 | { |
| 538 | DOUBLEST foo; |
| 539 | int inv; |
| 540 | |
| 541 | foo = unpack_double (VALUE_TYPE (val)(val)->type, VALUE_CONTENTS (val)((void)((val)->lazy && value_fetch_lazy(val)), ((char *) (val)->aligner.contents + (val)->embedded_offset)), &inv); |
| 542 | if (inv) |
| 543 | error ("Invalid floating value found in program."); |
| 544 | return foo; |
| 545 | } |
| 546 | /* Extract a value as a C pointer. Does not deallocate the value. |
| 547 | Note that val's type may not actually be a pointer; value_as_long |
| 548 | handles all the cases. */ |
| 549 | CORE_ADDR |
| 550 | value_as_address (struct value *val) |
| 551 | { |
| 552 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| 553 | whether we want this to be true eventually. */ |
| 554 | #if 0 |
| 555 | /* ADDR_BITS_REMOVE is wrong if we are being called for a |
| 556 | non-address (e.g. argument to "signal", "info break", etc.), or |
| 557 | for pointers to char, in which the low bits *are* significant. */ |
| 558 | return ADDR_BITS_REMOVE (value_as_long (val))(gdbarch_addr_bits_remove (current_gdbarch, value_as_long (val ))); |
| 559 | #else |
| 560 | |
| 561 | /* There are several targets (IA-64, PowerPC, and others) which |
| 562 | don't represent pointers to functions as simply the address of |
| 563 | the function's entry point. For example, on the IA-64, a |
| 564 | function pointer points to a two-word descriptor, generated by |
| 565 | the linker, which contains the function's entry point, and the |
| 566 | value the IA-64 "global pointer" register should have --- to |
| 567 | support position-independent code. The linker generates |
| 568 | descriptors only for those functions whose addresses are taken. |
| 569 | |
| 570 | On such targets, it's difficult for GDB to convert an arbitrary |
| 571 | function address into a function pointer; it has to either find |
| 572 | an existing descriptor for that function, or call malloc and |
| 573 | build its own. On some targets, it is impossible for GDB to |
| 574 | build a descriptor at all: the descriptor must contain a jump |
| 575 | instruction; data memory cannot be executed; and code memory |
| 576 | cannot be modified. |
| 577 | |
| 578 | Upon entry to this function, if VAL is a value of type `function' |
| 579 | (that is, TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FUNC), then |
| 580 | VALUE_ADDRESS (val) is the address of the function. This is what |
| 581 | you'll get if you evaluate an expression like `main'. The call |
| 582 | to COERCE_ARRAY below actually does all the usual unary |
| 583 | conversions, which includes converting values of type `function' |
| 584 | to `pointer to function'. This is the challenging conversion |
| 585 | discussed above. Then, `unpack_long' will convert that pointer |
| 586 | back into an address. |
| 587 | |
| 588 | So, suppose the user types `disassemble foo' on an architecture |
| 589 | with a strange function pointer representation, on which GDB |
| 590 | cannot build its own descriptors, and suppose further that `foo' |
| 591 | has no linker-built descriptor. The address->pointer conversion |
| 592 | will signal an error and prevent the command from running, even |
| 593 | though the next step would have been to convert the pointer |
| 594 | directly back into the same address. |
| 595 | |
| 596 | The following shortcut avoids this whole mess. If VAL is a |
| 597 | function, just return its address directly. */ |
| 598 | if (TYPE_CODE (VALUE_TYPE (val))((val)->type)->main_type->code == TYPE_CODE_FUNC |
| 599 | || TYPE_CODE (VALUE_TYPE (val))((val)->type)->main_type->code == TYPE_CODE_METHOD) |
| 600 | return VALUE_ADDRESS (val)(val)->location.address; |
| 601 | |
| 602 | COERCE_ARRAY (val)do { do { struct type *value_type_arg_tmp = check_typedef ((val )->type); if ((value_type_arg_tmp)->main_type->code == TYPE_CODE_REF) val = value_at_lazy ((value_type_arg_tmp)-> main_type->target_type, unpack_pointer ((val)->type, (( void)((val)->lazy && value_fetch_lazy(val)), ((char *) (val)->aligner.contents + (val)->embedded_offset))) , ((val)->bfd_section)); } while (0); if (current_language ->c_style_arrays && ((val)->type)->main_type ->code == TYPE_CODE_ARRAY) val = value_coerce_array (val); if (((val)->type)->main_type->code == TYPE_CODE_FUNC ) val = value_coerce_function (val); } while (0); |
| 603 | |
| 604 | /* Some architectures (e.g. Harvard), map instruction and data |
| 605 | addresses onto a single large unified address space. For |
| 606 | instance: An architecture may consider a large integer in the |
| 607 | range 0x10000000 .. 0x1000ffff to already represent a data |
| 608 | addresses (hence not need a pointer to address conversion) while |
| 609 | a small integer would still need to be converted integer to |
| 610 | pointer to address. Just assume such architectures handle all |
| 611 | integer conversions in a single function. */ |
| 612 | |
| 613 | /* JimB writes: |
| 614 | |
| 615 | I think INTEGER_TO_ADDRESS is a good idea as proposed --- but we |
| 616 | must admonish GDB hackers to make sure its behavior matches the |
| 617 | compiler's, whenever possible. |
| 618 | |
| 619 | In general, I think GDB should evaluate expressions the same way |
| 620 | the compiler does. When the user copies an expression out of |
| 621 | their source code and hands it to a `print' command, they should |
| 622 | get the same value the compiler would have computed. Any |
| 623 | deviation from this rule can cause major confusion and annoyance, |
| 624 | and needs to be justified carefully. In other words, GDB doesn't |
| 625 | really have the freedom to do these conversions in clever and |
| 626 | useful ways. |
| 627 | |
| 628 | AndrewC pointed out that users aren't complaining about how GDB |
| 629 | casts integers to pointers; they are complaining that they can't |
| 630 | take an address from a disassembly listing and give it to `x/i'. |
| 631 | This is certainly important. |
| 632 | |
| 633 | Adding an architecture method like INTEGER_TO_ADDRESS certainly |
| 634 | makes it possible for GDB to "get it right" in all circumstances |
| 635 | --- the target has complete control over how things get done, so |
| 636 | people can Do The Right Thing for their target without breaking |
| 637 | anyone else. The standard doesn't specify how integers get |
| 638 | converted to pointers; usually, the ABI doesn't either, but |
| 639 | ABI-specific code is a more reasonable place to handle it. */ |
| 640 | |
| 641 | if (TYPE_CODE (VALUE_TYPE (val))((val)->type)->main_type->code != TYPE_CODE_PTR |
| 642 | && TYPE_CODE (VALUE_TYPE (val))((val)->type)->main_type->code != TYPE_CODE_REF |
| 643 | && INTEGER_TO_ADDRESS_P ()(gdbarch_integer_to_address_p (current_gdbarch))) |
| 644 | return INTEGER_TO_ADDRESS (VALUE_TYPE (val), VALUE_CONTENTS (val))(gdbarch_integer_to_address (current_gdbarch, (val)->type, ((void)((val)->lazy && value_fetch_lazy(val)), (( char *) (val)->aligner.contents + (val)->embedded_offset )))); |
| 645 | |
| 646 | return unpack_long (VALUE_TYPE (val)(val)->type, VALUE_CONTENTS (val)((void)((val)->lazy && value_fetch_lazy(val)), ((char *) (val)->aligner.contents + (val)->embedded_offset))); |
| 647 | #endif |
| 648 | } |
| 649 | |
| 650 | /* Unpack raw data (copied from debugee, target byte order) at VALADDR |
| 651 | as a long, or as a double, assuming the raw data is described |
| 652 | by type TYPE. Knows how to convert different sizes of values |
| 653 | and can convert between fixed and floating point. We don't assume |
| 654 | any alignment for the raw data. Return value is in host byte order. |
| 655 | |
| 656 | If you want functions and arrays to be coerced to pointers, and |
| 657 | references to be dereferenced, call value_as_long() instead. |
| 658 | |
| 659 | C++: It is assumed that the front-end has taken care of |
| 660 | all matters concerning pointers to members. A pointer |
| 661 | to member which reaches here is considered to be equivalent |
| 662 | to an INT (or some size). After all, it is only an offset. */ |
| 663 | |
| 664 | LONGESTlong |
| 665 | unpack_long (struct type *type, const char *valaddr) |
| 666 | { |
| 667 | enum type_code code = TYPE_CODE (type)(type)->main_type->code; |
| 668 | int len = TYPE_LENGTH (type)(type)->length; |
| 669 | int nosign = TYPE_UNSIGNED (type)((type)->main_type->flags & (1 << 0)); |
| 670 | |
| 671 | if (current_language->la_language == language_scm |
| 672 | && is_scmvalue_type (type)) |
| 673 | return scm_unpack (type, valaddr, TYPE_CODE_INT); |
| 674 | |
| 675 | switch (code) |
| 676 | { |
| 677 | case TYPE_CODE_TYPEDEF: |
| 678 | return unpack_long (check_typedef (type), valaddr); |
| 679 | case TYPE_CODE_ENUM: |
| 680 | case TYPE_CODE_BOOL: |
| 681 | case TYPE_CODE_INT: |
| 682 | case TYPE_CODE_CHAR: |
| 683 | case TYPE_CODE_RANGE: |
| 684 | if (nosign) |
| 685 | return extract_unsigned_integer (valaddr, len); |
| 686 | else |
| 687 | return extract_signed_integer (valaddr, len); |
| 688 | |
| 689 | case TYPE_CODE_FLT: |
| 690 | return extract_typed_floating (valaddr, type); |
| 691 | |
| 692 | case TYPE_CODE_PTR: |
| 693 | case TYPE_CODE_REF: |
| 694 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| 695 | whether we want this to be true eventually. */ |
| 696 | return extract_typed_address (valaddr, type); |
| 697 | |
| 698 | case TYPE_CODE_MEMBER: |
| 699 | error ("not implemented: member types in unpack_long"); |
| 700 | |
| 701 | default: |
| 702 | error ("Value can't be converted to integer."); |
| 703 | } |
| 704 | return 0; /* Placate lint. */ |
| 705 | } |
| 706 | |
| 707 | /* Return a double value from the specified type and address. |
| 708 | INVP points to an int which is set to 0 for valid value, |
| 709 | 1 for invalid value (bad float format). In either case, |
| 710 | the returned double is OK to use. Argument is in target |
| 711 | format, result is in host format. */ |
| 712 | |
| 713 | DOUBLEST |
| 714 | unpack_double (struct type *type, const char *valaddr, int *invp) |
| 715 | { |
| 716 | enum type_code code; |
| 717 | int len; |
| 718 | int nosign; |
| 719 | |
| 720 | *invp = 0; /* Assume valid. */ |
| 721 | CHECK_TYPEDEF (type)(type) = check_typedef (type); |
| 722 | code = TYPE_CODE (type)(type)->main_type->code; |
| 723 | len = TYPE_LENGTH (type)(type)->length; |
| 724 | nosign = TYPE_UNSIGNED (type)((type)->main_type->flags & (1 << 0)); |
| 725 | if (code == TYPE_CODE_FLT) |
| 726 | { |
| 727 | /* NOTE: cagney/2002-02-19: There was a test here to see if the |
| 728 | floating-point value was valid (using the macro |
| 729 | INVALID_FLOAT). That test/macro have been removed. |
| 730 | |
| 731 | It turns out that only the VAX defined this macro and then |
| 732 | only in a non-portable way. Fixing the portability problem |
| 733 | wouldn't help since the VAX floating-point code is also badly |
| 734 | bit-rotten. The target needs to add definitions for the |
| 735 | methods TARGET_FLOAT_FORMAT and TARGET_DOUBLE_FORMAT - these |
| 736 | exactly describe the target floating-point format. The |
| 737 | problem here is that the corresponding floatformat_vax_f and |
| 738 | floatformat_vax_d values these methods should be set to are |
| 739 | also not defined either. Oops! |
| 740 | |
| 741 | Hopefully someone will add both the missing floatformat |
| 742 | definitions and the new cases for floatformat_is_valid (). */ |
| 743 | |
| 744 | if (!floatformat_is_valid (floatformat_from_type (type), valaddr)) |
| 745 | { |
| 746 | *invp = 1; |
| 747 | return 0.0; |
| 748 | } |
| 749 | |
| 750 | return extract_typed_floating (valaddr, type); |
| 751 | } |
| 752 | else if (nosign) |
| 753 | { |
| 754 | /* Unsigned -- be sure we compensate for signed LONGEST. */ |
| 755 | return (ULONGESTunsigned long) unpack_long (type, valaddr); |
| 756 | } |
| 757 | else |
| 758 | { |
| 759 | /* Signed -- we are OK with unpack_long. */ |
| 760 | return unpack_long (type, valaddr); |
| 761 | } |
| 762 | } |
| 763 | |
| 764 | /* Unpack raw data (copied from debugee, target byte order) at VALADDR |
| 765 | as a CORE_ADDR, assuming the raw data is described by type TYPE. |
| 766 | We don't assume any alignment for the raw data. Return value is in |
| 767 | host byte order. |
| 768 | |
| 769 | If you want functions and arrays to be coerced to pointers, and |
| 770 | references to be dereferenced, call value_as_address() instead. |
| 771 | |
| 772 | C++: It is assumed that the front-end has taken care of |
| 773 | all matters concerning pointers to members. A pointer |
| 774 | to member which reaches here is considered to be equivalent |
| 775 | to an INT (or some size). After all, it is only an offset. */ |
| 776 | |
| 777 | CORE_ADDR |
| 778 | unpack_pointer (struct type *type, const char *valaddr) |
| 779 | { |
| 780 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| 781 | whether we want this to be true eventually. */ |
| 782 | return unpack_long (type, valaddr); |
| 783 | } |
| 784 | |
| 785 | |
| 786 | /* Get the value of the FIELDN'th field (which must be static) of |
| 787 | TYPE. Return NULL if the field doesn't exist or has been |
| 788 | optimized out. */ |
| 789 | |
| 790 | struct value * |
| 791 | value_static_field (struct type *type, int fieldno) |
| 792 | { |
| 793 | struct value *retval; |
| 794 | |
| 795 | if (TYPE_FIELD_STATIC_HAS_ADDR (type, fieldno)((type)->main_type->fields[fieldno].static_kind == 2)) |
| 796 | { |
| 797 | retval = value_at (TYPE_FIELD_TYPE (type, fieldno)(((type)->main_type->fields[fieldno]).type), |
| 798 | TYPE_FIELD_STATIC_PHYSADDR (type, fieldno)(((type)->main_type->fields[fieldno]).loc.physaddr), |
| 799 | NULL((void*)0)); |
| 800 | } |
| 801 | else |
| 802 | { |
| 803 | char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno)(((type)->main_type->fields[fieldno]).loc.physname); |
| 804 | struct symbol *sym = lookup_symbol (phys_name, 0, VAR_DOMAIN, 0, NULL((void*)0)); |
| 805 | if (sym == NULL((void*)0)) |
| 806 | { |
| 807 | /* With some compilers, e.g. HP aCC, static data members are reported |
| 808 | as non-debuggable symbols */ |
| 809 | struct minimal_symbol *msym = lookup_minimal_symbol (phys_name, NULL((void*)0), NULL((void*)0)); |
| 810 | if (!msym) |
| 811 | return NULL((void*)0); |
| 812 | else |
| 813 | { |
| 814 | retval = value_at (TYPE_FIELD_TYPE (type, fieldno)(((type)->main_type->fields[fieldno]).type), |
| 815 | SYMBOL_VALUE_ADDRESS (msym)(msym)->ginfo.value.address, |
| 816 | SYMBOL_BFD_SECTION (msym)(msym)->ginfo.bfd_section); |
| 817 | } |
| 818 | } |
| 819 | else |
| 820 | { |
| 821 | /* SYM should never have a SYMBOL_CLASS which will require |
| 822 | read_var_value to use the FRAME parameter. */ |
| 823 | if (symbol_read_needs_frame (sym)) |
| 824 | warning ("static field's value depends on the current " |
| 825 | "frame - bad debug info?"); |
| 826 | retval = read_var_value (sym, NULL((void*)0)); |
| 827 | } |
| 828 | if (retval && VALUE_LVAL (retval)(retval)->lval == lval_memory) |
| 829 | SET_FIELD_PHYSADDR (TYPE_FIELD (type, fieldno),(((type)->main_type->fields[fieldno]).static_kind = 2, ( ((type)->main_type->fields[fieldno]).loc.physaddr) = (( retval)->location.address)) |
| 830 | VALUE_ADDRESS (retval))(((type)->main_type->fields[fieldno]).static_kind = 2, ( ((type)->main_type->fields[fieldno]).loc.physaddr) = (( retval)->location.address)); |
| 831 | } |
| 832 | return retval; |
| 833 | } |
| 834 | |
| 835 | /* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE. |
| 836 | You have to be careful here, since the size of the data area for the value |
| 837 | is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger |
| 838 | than the old enclosing type, you have to allocate more space for the data. |
| 839 | The return value is a pointer to the new version of this value structure. */ |
| 840 | |
| 841 | struct value * |
| 842 | value_change_enclosing_type (struct value *val, struct type *new_encl_type) |
| 843 | { |
| 844 | if (TYPE_LENGTH (new_encl_type)(new_encl_type)->length <= TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val))((val)->enclosing_type)->length) |
| 845 | { |
| 846 | VALUE_ENCLOSING_TYPE (val)(val)->enclosing_type = new_encl_type; |
| 847 | return val; |
| 848 | } |
| 849 | else |
| 850 | { |
| 851 | struct value *new_val; |
| 852 | struct value *prev; |
| 853 | |
| 854 | new_val = (struct value *) xrealloc (val, sizeof (struct value) + TYPE_LENGTH (new_encl_type)(new_encl_type)->length); |
| 855 | |
| 856 | VALUE_ENCLOSING_TYPE (new_val)(new_val)->enclosing_type = new_encl_type; |
| 857 | |
| 858 | /* We have to make sure this ends up in the same place in the value |
| 859 | chain as the original copy, so it's clean-up behavior is the same. |
| 860 | If the value has been released, this is a waste of time, but there |
| 861 | is no way to tell that in advance, so... */ |
| 862 | |
| 863 | if (val != all_values) |
| 864 | { |
| 865 | for (prev = all_values; prev != NULL((void*)0); prev = prev->next) |
| 866 | { |
| 867 | if (prev->next == val) |
| 868 | { |
| 869 | prev->next = new_val; |
| 870 | break; |
| 871 | } |
| 872 | } |
| 873 | } |
| 874 | |
| 875 | return new_val; |
| 876 | } |
| 877 | } |
| 878 | |
| 879 | /* Given a value ARG1 (offset by OFFSET bytes) |
| 880 | of a struct or union type ARG_TYPE, |
| 881 | extract and return the value of one of its (non-static) fields. |
| 882 | FIELDNO says which field. */ |
| 883 | |
| 884 | struct value * |
| 885 | value_primitive_field (struct value *arg1, int offset, |
| 886 | int fieldno, struct type *arg_type) |
| 887 | { |
| 888 | struct value *v; |
| 889 | struct type *type; |
| 890 | |
| 891 | CHECK_TYPEDEF (arg_type)(arg_type) = check_typedef (arg_type); |
| 892 | type = TYPE_FIELD_TYPE (arg_type, fieldno)(((arg_type)->main_type->fields[fieldno]).type); |
| 893 | |
| 894 | /* Handle packed fields */ |
| 895 | |
| 896 | if (TYPE_FIELD_BITSIZE (arg_type, fieldno)(((arg_type)->main_type->fields[fieldno]).bitsize)) |
| 897 | { |
| 898 | v = value_from_longest (type, |
| 899 | unpack_field_as_long (arg_type, |
| 900 | VALUE_CONTENTS (arg1)((void)((arg1)->lazy && value_fetch_lazy(arg1)), ( (char *) (arg1)->aligner.contents + (arg1)->embedded_offset )) |
| 901 | + offset, |
| 902 | fieldno)); |
| 903 | VALUE_BITPOS (v)(v)->bitpos = TYPE_FIELD_BITPOS (arg_type, fieldno)(((arg_type)->main_type->fields[fieldno]).loc.bitpos) % 8; |
| 904 | VALUE_BITSIZE (v)(v)->bitsize = TYPE_FIELD_BITSIZE (arg_type, fieldno)(((arg_type)->main_type->fields[fieldno]).bitsize); |
| 905 | VALUE_OFFSET (v)(v)->offset = VALUE_OFFSET (arg1)(arg1)->offset + offset |
| 906 | + TYPE_FIELD_BITPOS (arg_type, fieldno)(((arg_type)->main_type->fields[fieldno]).loc.bitpos) / 8; |
| 907 | } |
| 908 | else if (fieldno < TYPE_N_BASECLASSES (arg_type)(arg_type)->main_type->type_specific.cplus_stuff->n_baseclasses) |
| 909 | { |
| 910 | /* This field is actually a base subobject, so preserve the |
| 911 | entire object's contents for later references to virtual |
| 912 | bases, etc. */ |
| 913 | v = allocate_value (VALUE_ENCLOSING_TYPE (arg1)(arg1)->enclosing_type); |
| 914 | VALUE_TYPE (v)(v)->type = type; |
| 915 | if (VALUE_LAZY (arg1)(arg1)->lazy) |
| 916 | VALUE_LAZY (v)(v)->lazy = 1; |
| 917 | else |
| 918 | memcpy (VALUE_CONTENTS_ALL_RAW (v)((char *) (v)->aligner.contents), VALUE_CONTENTS_ALL_RAW (arg1)((char *) (arg1)->aligner.contents), |
| 919 | TYPE_LENGTH (VALUE_ENCLOSING_TYPE (arg1))((arg1)->enclosing_type)->length); |
| 920 | VALUE_OFFSET (v)(v)->offset = VALUE_OFFSET (arg1)(arg1)->offset; |
| 921 | VALUE_EMBEDDED_OFFSET (v)((v)->embedded_offset) |
| 922 | = offset + |
| 923 | VALUE_EMBEDDED_OFFSET (arg1)((arg1)->embedded_offset) + |
| 924 | TYPE_FIELD_BITPOS (arg_type, fieldno)(((arg_type)->main_type->fields[fieldno]).loc.bitpos) / 8; |
| 925 | } |
| 926 | else |
| 927 | { |
| 928 | /* Plain old data member */ |
| 929 | offset += TYPE_FIELD_BITPOS (arg_type, fieldno)(((arg_type)->main_type->fields[fieldno]).loc.bitpos) / 8; |
| 930 | v = allocate_value (type); |
| 931 | if (VALUE_LAZY (arg1)(arg1)->lazy) |
| 932 | VALUE_LAZY (v)(v)->lazy = 1; |
| 933 | else |
| 934 | memcpy (VALUE_CONTENTS_RAW (v)((char *) (v)->aligner.contents + (v)->embedded_offset), |
| 935 | VALUE_CONTENTS_RAW (arg1)((char *) (arg1)->aligner.contents + (arg1)->embedded_offset ) + offset, |
| 936 | TYPE_LENGTH (type)(type)->length); |
| 937 | VALUE_OFFSET (v)(v)->offset = VALUE_OFFSET (arg1)(arg1)->offset + offset |
| 938 | + VALUE_EMBEDDED_OFFSET (arg1)((arg1)->embedded_offset); |
| 939 | } |
| 940 | VALUE_LVAL (v)(v)->lval = VALUE_LVAL (arg1)(arg1)->lval; |
| 941 | if (VALUE_LVAL (arg1)(arg1)->lval == lval_internalvar) |
| 942 | VALUE_LVAL (v)(v)->lval = lval_internalvar_component; |
| 943 | VALUE_ADDRESS (v)(v)->location.address = VALUE_ADDRESS (arg1)(arg1)->location.address; |
| 944 | VALUE_REGNO (v)(v)->regno = VALUE_REGNO (arg1)(arg1)->regno; |
| 945 | /* VALUE_OFFSET (v) = VALUE_OFFSET (arg1) + offset |
| 946 | + TYPE_FIELD_BITPOS (arg_type, fieldno) / 8; */ |
| 947 | return v; |
| 948 | } |
| 949 | |
| 950 | /* Given a value ARG1 of a struct or union type, |
| 951 | extract and return the value of one of its (non-static) fields. |
| 952 | FIELDNO says which field. */ |
| 953 | |
| 954 | struct value * |
| 955 | value_field (struct value *arg1, int fieldno) |
| 956 | { |
| 957 | return value_primitive_field (arg1, 0, fieldno, VALUE_TYPE (arg1)(arg1)->type); |
| 958 | } |
| 959 | |
| 960 | /* Return a non-virtual function as a value. |
| 961 | F is the list of member functions which contains the desired method. |
| 962 | J is an index into F which provides the desired method. |
| 963 | |
| 964 | We only use the symbol for its address, so be happy with either a |
| 965 | full symbol or a minimal symbol. |
| 966 | */ |
| 967 | |
| 968 | struct value * |
| 969 | value_fn_field (struct value **arg1p, struct fn_field *f, int j, struct type *type, |
| 970 | int offset) |
| 971 | { |
| 972 | struct value *v; |
| 973 | struct type *ftype = TYPE_FN_FIELD_TYPE (f, j)(f)[j].type; |
| 974 | char *physname = TYPE_FN_FIELD_PHYSNAME (f, j)(f)[j].physname; |
| 975 | struct symbol *sym; |
| 976 | struct minimal_symbol *msym; |
| 977 | |
| 978 | sym = lookup_symbol (physname, 0, VAR_DOMAIN, 0, NULL((void*)0)); |
| 979 | if (sym != NULL((void*)0)) |
| 980 | { |
| 981 | msym = NULL((void*)0); |
| 982 | } |
| 983 | else |
| 984 | { |
| 985 | gdb_assert (sym == NULL)((void) ((sym == ((void*)0)) ? 0 : (internal_error ("/usr/src/gnu/usr.bin/binutils/gdb/values.c" , 985, "%s: Assertion `%s' failed.", __PRETTY_FUNCTION__, "sym == NULL" ), 0))); |
| 986 | msym = lookup_minimal_symbol (physname, NULL((void*)0), NULL((void*)0)); |
| 987 | if (msym == NULL((void*)0)) |
| 988 | return NULL((void*)0); |
| 989 | } |
| 990 | |
| 991 | v = allocate_value (ftype); |
| 992 | if (sym) |
| 993 | { |
| 994 | VALUE_ADDRESS (v)(v)->location.address = BLOCK_START (SYMBOL_BLOCK_VALUE (sym))((sym)->ginfo.value.block)->startaddr; |
| 995 | } |
| 996 | else |
| 997 | { |
| 998 | VALUE_ADDRESS (v)(v)->location.address = SYMBOL_VALUE_ADDRESS (msym)(msym)->ginfo.value.address; |
| 999 | } |
| 1000 | |
| 1001 | if (arg1p) |
| 1002 | { |
| 1003 | if (type != VALUE_TYPE (*arg1p)(*arg1p)->type) |
| 1004 | *arg1p = value_ind (value_cast (lookup_pointer_type (type), |
| 1005 | value_addr (*arg1p))); |
| 1006 | |
| 1007 | /* Move the `this' pointer according to the offset. |
| 1008 | VALUE_OFFSET (*arg1p) += offset; |
| 1009 | */ |
| 1010 | } |
| 1011 | |
| 1012 | return v; |
| 1013 | } |
| 1014 | |
| 1015 | |
| 1016 | /* Unpack a field FIELDNO of the specified TYPE, from the anonymous object at |
| 1017 | VALADDR. |
| 1018 | |
| 1019 | Extracting bits depends on endianness of the machine. Compute the |
| 1020 | number of least significant bits to discard. For big endian machines, |
| 1021 | we compute the total number of bits in the anonymous object, subtract |
| 1022 | off the bit count from the MSB of the object to the MSB of the |
| 1023 | bitfield, then the size of the bitfield, which leaves the LSB discard |
| 1024 | count. For little endian machines, the discard count is simply the |
| 1025 | number of bits from the LSB of the anonymous object to the LSB of the |
| 1026 | bitfield. |
| 1027 | |
| 1028 | If the field is signed, we also do sign extension. */ |
| 1029 | |
| 1030 | LONGESTlong |
| 1031 | unpack_field_as_long (struct type *type, const char *valaddr, int fieldno) |
| 1032 | { |
| 1033 | ULONGESTunsigned long val; |
| 1034 | ULONGESTunsigned long valmask; |
| 1035 | int bitpos = TYPE_FIELD_BITPOS (type, fieldno)(((type)->main_type->fields[fieldno]).loc.bitpos); |
| 1036 | int bitsize = TYPE_FIELD_BITSIZE (type, fieldno)(((type)->main_type->fields[fieldno]).bitsize); |
| 1037 | int lsbcount; |
| 1038 | struct type *field_type; |
| 1039 | |
| 1040 | val = extract_unsigned_integer (valaddr + bitpos / 8, sizeof (val)); |
| 1041 | field_type = TYPE_FIELD_TYPE (type, fieldno)(((type)->main_type->fields[fieldno]).type); |
| 1042 | CHECK_TYPEDEF (field_type)(field_type) = check_typedef (field_type); |
| 1043 | |
| 1044 | /* Extract bits. See comment above. */ |
| 1045 | |
| 1046 | if (BITS_BIG_ENDIAN((gdbarch_byte_order (current_gdbarch)) == BFD_ENDIAN_BIG)) |
| 1047 | lsbcount = (sizeof val * 8 - bitpos % 8 - bitsize); |
| 1048 | else |
| 1049 | lsbcount = (bitpos % 8); |
| 1050 | val >>= lsbcount; |
| 1051 | |
| 1052 | /* If the field does not entirely fill a LONGEST, then zero the sign bits. |
| 1053 | If the field is signed, and is negative, then sign extend. */ |
| 1054 | |
| 1055 | if ((bitsize > 0) && (bitsize < 8 * (int) sizeof (val))) |
| 1056 | { |
| 1057 | valmask = (((ULONGESTunsigned long) 1) << bitsize) - 1; |
| 1058 | val &= valmask; |
| 1059 | if (!TYPE_UNSIGNED (field_type)((field_type)->main_type->flags & (1 << 0))) |
| 1060 | { |
| 1061 | if (val & (valmask ^ (valmask >> 1))) |
| 1062 | { |
| 1063 | val |= ~valmask; |
| 1064 | } |
| 1065 | } |
| 1066 | } |
| 1067 | return (val); |
| 1068 | } |
| 1069 | |
| 1070 | /* Modify the value of a bitfield. ADDR points to a block of memory in |
| 1071 | target byte order; the bitfield starts in the byte pointed to. FIELDVAL |
| 1072 | is the desired value of the field, in host byte order. BITPOS and BITSIZE |
| 1073 | indicate which bits (in target bit order) comprise the bitfield. */ |
| 1074 | |
| 1075 | void |
| 1076 | modify_field (char *addr, LONGESTlong fieldval, int bitpos, int bitsize) |
| 1077 | { |
| 1078 | LONGESTlong oword; |
| 1079 | |
| 1080 | /* If a negative fieldval fits in the field in question, chop |
| 1081 | off the sign extension bits. */ |
| 1082 | if (bitsize < (8 * (int) sizeof (fieldval)) |
| 1083 | && (~fieldval & ~((1 << (bitsize - 1)) - 1)) == 0) |
| 1084 | fieldval = fieldval & ((1 << bitsize) - 1); |
| 1085 | |
| 1086 | /* Warn if value is too big to fit in the field in question. */ |
| 1087 | if (bitsize < (8 * (int) sizeof (fieldval)) |
| 1088 | && 0 != (fieldval & ~((1 << bitsize) - 1))) |
| 1089 | { |
| 1090 | /* FIXME: would like to include fieldval in the message, but |
| 1091 | we don't have a sprintf_longest. */ |
| 1092 | warning ("Value does not fit in %d bits.", bitsize); |
| 1093 | |
| 1094 | /* Truncate it, otherwise adjoining fields may be corrupted. */ |
| 1095 | fieldval = fieldval & ((1 << bitsize) - 1); |
| 1096 | } |
| 1097 | |
| 1098 | oword = extract_signed_integer (addr, sizeof oword); |
| 1099 | |
| 1100 | /* Shifting for bit field depends on endianness of the target machine. */ |
| 1101 | if (BITS_BIG_ENDIAN((gdbarch_byte_order (current_gdbarch)) == BFD_ENDIAN_BIG)) |
| 1102 | bitpos = sizeof (oword) * 8 - bitpos - bitsize; |
| 1103 | |
| 1104 | /* Mask out old value, while avoiding shifts >= size of oword */ |
| 1105 | if (bitsize < 8 * (int) sizeof (oword)) |
| 1106 | oword &= ~(((((ULONGESTunsigned long) 1) << bitsize) - 1) << bitpos); |
| 1107 | else |
| 1108 | oword &= ~((~(ULONGESTunsigned long) 0) << bitpos); |
| 1109 | oword |= fieldval << bitpos; |
| 1110 | |
| 1111 | store_signed_integer (addr, sizeof oword, oword); |
| 1112 | } |
| 1113 | |
| 1114 | /* Convert C numbers into newly allocated values */ |
| 1115 | |
| 1116 | struct value * |
| 1117 | value_from_longest (struct type *type, LONGESTlong num) |
| 1118 | { |
| 1119 | struct value *val = allocate_value (type); |
| 1120 | enum type_code code; |
| 1121 | int len; |
| 1122 | retry: |
| 1123 | code = TYPE_CODE (type)(type)->main_type->code; |
| 1124 | len = TYPE_LENGTH (type)(type)->length; |
| 1125 | |
| 1126 | switch (code) |
| 1127 | { |
| 1128 | case TYPE_CODE_TYPEDEF: |
| 1129 | type = check_typedef (type); |
| 1130 | goto retry; |
| 1131 | case TYPE_CODE_INT: |
| 1132 | case TYPE_CODE_CHAR: |
| 1133 | case TYPE_CODE_ENUM: |
| 1134 | case TYPE_CODE_BOOL: |
| 1135 | case TYPE_CODE_RANGE: |
| 1136 | store_signed_integer (VALUE_CONTENTS_RAW (val)((char *) (val)->aligner.contents + (val)->embedded_offset ), len, num); |
| 1137 | break; |
| 1138 | |
| 1139 | case TYPE_CODE_REF: |
| 1140 | case TYPE_CODE_PTR: |
| 1141 | store_typed_address (VALUE_CONTENTS_RAW (val)((char *) (val)->aligner.contents + (val)->embedded_offset ), type, (CORE_ADDR) num); |
| 1142 | break; |
| 1143 | |
| 1144 | default: |
| 1145 | error ("Unexpected type (%d) encountered for integer constant.", code); |
| 1146 | } |
| 1147 | return val; |
| 1148 | } |
| 1149 | |
| 1150 | |
| 1151 | /* Create a value representing a pointer of type TYPE to the address |
| 1152 | ADDR. */ |
| 1153 | struct value * |
| 1154 | value_from_pointer (struct type *type, CORE_ADDR addr) |
| 1155 | { |
| 1156 | struct value *val = allocate_value (type); |
| 1157 | store_typed_address (VALUE_CONTENTS_RAW (val)((char *) (val)->aligner.contents + (val)->embedded_offset ), type, addr); |
| 1158 | return val; |
| 1159 | } |
| 1160 | |
| 1161 | |
| 1162 | /* Create a value for a string constant to be stored locally |
| 1163 | (not in the inferior's memory space, but in GDB memory). |
| 1164 | This is analogous to value_from_longest, which also does not |
| 1165 | use inferior memory. String shall NOT contain embedded nulls. */ |
| 1166 | |
| 1167 | struct value * |
| 1168 | value_from_string (char *ptr) |
| 1169 | { |
| 1170 | struct value *val; |
| 1171 | int len = strlen (ptr); |
| 1172 | int lowbound = current_language->string_lower_bound; |
| 1173 | struct type *string_char_type; |
| 1174 | struct type *rangetype; |
| 1175 | struct type *stringtype; |
| 1176 | |
| 1177 | rangetype = create_range_type ((struct type *) NULL((void*)0), |
| 1178 | builtin_type_int, |
| 1179 | lowbound, len + lowbound - 1); |
| 1180 | string_char_type = language_string_char_type (current_language, |
| 1181 | current_gdbarch); |
| 1182 | stringtype = create_array_type ((struct type *) NULL((void*)0), |
| 1183 | string_char_type, |
| 1184 | rangetype); |
| 1185 | val = allocate_value (stringtype); |
| 1186 | memcpy (VALUE_CONTENTS_RAW (val)((char *) (val)->aligner.contents + (val)->embedded_offset ), ptr, len); |
| 1187 | return val; |
| 1188 | } |
| 1189 | |
| 1190 | struct value * |
| 1191 | value_from_double (struct type *type, DOUBLEST num) |
| 1192 | { |
| 1193 | struct value *val = allocate_value (type); |
| 1194 | struct type *base_type = check_typedef (type); |
| 1195 | enum type_code code = TYPE_CODE (base_type)(base_type)->main_type->code; |
| 1196 | int len = TYPE_LENGTH (base_type)(base_type)->length; |
Value stored to 'len' during its initialization is never read | |
| 1197 | |
| 1198 | if (code == TYPE_CODE_FLT) |
| 1199 | { |
| 1200 | store_typed_floating (VALUE_CONTENTS_RAW (val)((char *) (val)->aligner.contents + (val)->embedded_offset ), base_type, num); |
| 1201 | } |
| 1202 | else |
| 1203 | error ("Unexpected type encountered for floating constant."); |
| 1204 | |
| 1205 | return val; |
| 1206 | } |
| 1207 | |
| 1208 | |
| 1209 | /* Should we use DEPRECATED_EXTRACT_STRUCT_VALUE_ADDRESS instead of |
| 1210 | EXTRACT_RETURN_VALUE? GCC_P is true if compiled with gcc and TYPE |
| 1211 | is the type (which is known to be struct, union or array). |
| 1212 | |
| 1213 | On most machines, the struct convention is used unless we are |
| 1214 | using gcc and the type is of a special size. */ |
| 1215 | /* As of about 31 Mar 93, GCC was changed to be compatible with the |
| 1216 | native compiler. GCC 2.3.3 was the last release that did it the |
| 1217 | old way. Since gcc2_compiled was not changed, we have no |
| 1218 | way to correctly win in all cases, so we just do the right thing |
| 1219 | for gcc1 and for gcc2 after this change. Thus it loses for gcc |
| 1220 | 2.0-2.3.3. This is somewhat unfortunate, but changing gcc2_compiled |
| 1221 | would cause more chaos than dealing with some struct returns being |
| 1222 | handled wrong. */ |
| 1223 | /* NOTE: cagney/2004-06-13: Deleted check for "gcc_p". GCC 1.x is |
| 1224 | dead. */ |
| 1225 | |
| 1226 | int |
| 1227 | generic_use_struct_convention (int gcc_p, struct type *value_type) |
| 1228 | { |
| 1229 | return !(TYPE_LENGTH (value_type)(value_type)->length == 1 |
| 1230 | || TYPE_LENGTH (value_type)(value_type)->length == 2 |
| 1231 | || TYPE_LENGTH (value_type)(value_type)->length == 4 |
| 1232 | || TYPE_LENGTH (value_type)(value_type)->length == 8); |
| 1233 | } |
| 1234 | |
| 1235 | /* Return true if the function returning the specified type is using |
| 1236 | the convention of returning structures in memory (passing in the |
| 1237 | address as a hidden first parameter). GCC_P is nonzero if compiled |
| 1238 | with GCC. */ |
| 1239 | |
| 1240 | int |
| 1241 | using_struct_return (struct type *value_type, int gcc_p) |
| 1242 | { |
| 1243 | enum type_code code = TYPE_CODE (value_type)(value_type)->main_type->code; |
| 1244 | |
| 1245 | if (code == TYPE_CODE_ERROR) |
| 1246 | error ("Function return type unknown."); |
| 1247 | |
| 1248 | if (code == TYPE_CODE_VOID) |
| 1249 | /* A void return value is never in memory. See also corresponding |
| 1250 | code in "print_return_value". */ |
| 1251 | return 0; |
| 1252 | |
| 1253 | /* Probe the architecture for the return-value convention. */ |
| 1254 | return (gdbarch_return_value (current_gdbarch, value_type, |
| 1255 | NULL((void*)0), NULL((void*)0), NULL((void*)0)) |
| 1256 | != RETURN_VALUE_REGISTER_CONVENTION); |
| 1257 | } |
| 1258 | |
| 1259 | void |
| 1260 | _initialize_values (void) |
| 1261 | { |
| 1262 | add_cmd ("convenience", no_class, show_convenience, |
| 1263 | "Debugger convenience (\"$foo\") variables.\n\ |
| 1264 | These variables are created when you assign them values;\n\ |
| 1265 | thus, \"print $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\n\ |
| 1266 | A few convenience variables are given values automatically:\n\ |
| 1267 | \"$_\"holds the last address examined with \"x\" or \"info lines\",\n\ |
| 1268 | \"$__\" holds the contents of the last address examined with \"x\".", |
| 1269 | &showlist); |
| 1270 | |
| 1271 | add_cmd ("values", no_class, show_values, |
| 1272 | "Elements of value history around item number IDX (or last ten).", |
| 1273 | &showlist); |
| 1274 | } |