1 /* Perform non-arithmetic operations on values, for GDB. 2 3 Copyright (C) 1986-2013 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 3 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, see <http://www.gnu.org/licenses/>. */ 19 20 #include "defs.h" 21 #include "symtab.h" 22 #include "gdbtypes.h" 23 #include "value.h" 24 #include "frame.h" 25 #include "inferior.h" 26 #include "gdbcore.h" 27 #include "target.h" 28 #include "demangle.h" 29 #include "language.h" 30 #include "gdbcmd.h" 31 #include "regcache.h" 32 #include "cp-abi.h" 33 #include "block.h" 34 #include "infcall.h" 35 #include "dictionary.h" 36 #include "cp-support.h" 37 #include "dfp.h" 38 #include "user-regs.h" 39 #include "tracepoint.h" 40 #include <errno.h> 41 #include "gdb_string.h" 42 #include "gdb_assert.h" 43 #include "cp-support.h" 44 #include "observer.h" 45 #include "objfiles.h" 46 #include "symtab.h" 47 #include "exceptions.h" 48 49 extern unsigned int overload_debug; 50 /* Local functions. */ 51 52 static int typecmp (int staticp, int varargs, int nargs, 53 struct field t1[], struct value *t2[]); 54 55 static struct value *search_struct_field (const char *, struct value *, 56 int, struct type *, int); 57 58 static struct value *search_struct_method (const char *, struct value **, 59 struct value **, 60 int, int *, struct type *); 61 62 static int find_oload_champ_namespace (struct value **, int, 63 const char *, const char *, 64 struct symbol ***, 65 struct badness_vector **, 66 const int no_adl); 67 68 static 69 int find_oload_champ_namespace_loop (struct value **, int, 70 const char *, const char *, 71 int, struct symbol ***, 72 struct badness_vector **, int *, 73 const int no_adl); 74 75 static int find_oload_champ (struct value **, int, int, int, 76 struct fn_field *, struct symbol **, 77 struct badness_vector **); 78 79 static int oload_method_static (int, struct fn_field *, int); 80 81 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE }; 82 83 static enum 84 oload_classification classify_oload_match (struct badness_vector *, 85 int, int); 86 87 static struct value *value_struct_elt_for_reference (struct type *, 88 int, struct type *, 89 char *, 90 struct type *, 91 int, enum noside); 92 93 static struct value *value_namespace_elt (const struct type *, 94 char *, int , enum noside); 95 96 static struct value *value_maybe_namespace_elt (const struct type *, 97 char *, int, 98 enum noside); 99 100 static CORE_ADDR allocate_space_in_inferior (int); 101 102 static struct value *cast_into_complex (struct type *, struct value *); 103 104 static struct fn_field *find_method_list (struct value **, const char *, 105 int, struct type *, int *, 106 struct type **, int *); 107 108 void _initialize_valops (void); 109 110 #if 0 111 /* Flag for whether we want to abandon failed expression evals by 112 default. */ 113 114 static int auto_abandon = 0; 115 #endif 116 117 int overload_resolution = 0; 118 static void 119 show_overload_resolution (struct ui_file *file, int from_tty, 120 struct cmd_list_element *c, 121 const char *value) 122 { 123 fprintf_filtered (file, _("Overload resolution in evaluating " 124 "C++ functions is %s.\n"), 125 value); 126 } 127 128 /* Find the address of function name NAME in the inferior. If OBJF_P 129 is non-NULL, *OBJF_P will be set to the OBJFILE where the function 130 is defined. */ 131 132 struct value * 133 find_function_in_inferior (const char *name, struct objfile **objf_p) 134 { 135 struct symbol *sym; 136 137 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0); 138 if (sym != NULL) 139 { 140 if (SYMBOL_CLASS (sym) != LOC_BLOCK) 141 { 142 error (_("\"%s\" exists in this program but is not a function."), 143 name); 144 } 145 146 if (objf_p) 147 *objf_p = SYMBOL_SYMTAB (sym)->objfile; 148 149 return value_of_variable (sym, NULL); 150 } 151 else 152 { 153 struct minimal_symbol *msymbol = 154 lookup_minimal_symbol (name, NULL, NULL); 155 156 if (msymbol != NULL) 157 { 158 struct objfile *objfile = msymbol_objfile (msymbol); 159 struct gdbarch *gdbarch = get_objfile_arch (objfile); 160 161 struct type *type; 162 CORE_ADDR maddr; 163 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char); 164 type = lookup_function_type (type); 165 type = lookup_pointer_type (type); 166 maddr = SYMBOL_VALUE_ADDRESS (msymbol); 167 168 if (objf_p) 169 *objf_p = objfile; 170 171 return value_from_pointer (type, maddr); 172 } 173 else 174 { 175 if (!target_has_execution) 176 error (_("evaluation of this expression " 177 "requires the target program to be active")); 178 else 179 error (_("evaluation of this expression requires the " 180 "program to have a function \"%s\"."), 181 name); 182 } 183 } 184 } 185 186 /* Allocate NBYTES of space in the inferior using the inferior's 187 malloc and return a value that is a pointer to the allocated 188 space. */ 189 190 struct value * 191 value_allocate_space_in_inferior (int len) 192 { 193 struct objfile *objf; 194 struct value *val = find_function_in_inferior ("malloc", &objf); 195 struct gdbarch *gdbarch = get_objfile_arch (objf); 196 struct value *blocklen; 197 198 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len); 199 val = call_function_by_hand (val, 1, &blocklen); 200 if (value_logical_not (val)) 201 { 202 if (!target_has_execution) 203 error (_("No memory available to program now: " 204 "you need to start the target first")); 205 else 206 error (_("No memory available to program: call to malloc failed")); 207 } 208 return val; 209 } 210 211 static CORE_ADDR 212 allocate_space_in_inferior (int len) 213 { 214 return value_as_long (value_allocate_space_in_inferior (len)); 215 } 216 217 /* Cast struct value VAL to type TYPE and return as a value. 218 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION 219 for this to work. Typedef to one of the codes is permitted. 220 Returns NULL if the cast is neither an upcast nor a downcast. */ 221 222 static struct value * 223 value_cast_structs (struct type *type, struct value *v2) 224 { 225 struct type *t1; 226 struct type *t2; 227 struct value *v; 228 229 gdb_assert (type != NULL && v2 != NULL); 230 231 t1 = check_typedef (type); 232 t2 = check_typedef (value_type (v2)); 233 234 /* Check preconditions. */ 235 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT 236 || TYPE_CODE (t1) == TYPE_CODE_UNION) 237 && !!"Precondition is that type is of STRUCT or UNION kind."); 238 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT 239 || TYPE_CODE (t2) == TYPE_CODE_UNION) 240 && !!"Precondition is that value is of STRUCT or UNION kind"); 241 242 if (TYPE_NAME (t1) != NULL 243 && TYPE_NAME (t2) != NULL 244 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2))) 245 return NULL; 246 247 /* Upcasting: look in the type of the source to see if it contains the 248 type of the target as a superclass. If so, we'll need to 249 offset the pointer rather than just change its type. */ 250 if (TYPE_NAME (t1) != NULL) 251 { 252 v = search_struct_field (type_name_no_tag (t1), 253 v2, 0, t2, 1); 254 if (v) 255 return v; 256 } 257 258 /* Downcasting: look in the type of the target to see if it contains the 259 type of the source as a superclass. If so, we'll need to 260 offset the pointer rather than just change its type. */ 261 if (TYPE_NAME (t2) != NULL) 262 { 263 /* Try downcasting using the run-time type of the value. */ 264 int full, top, using_enc; 265 struct type *real_type; 266 267 real_type = value_rtti_type (v2, &full, &top, &using_enc); 268 if (real_type) 269 { 270 v = value_full_object (v2, real_type, full, top, using_enc); 271 v = value_at_lazy (real_type, value_address (v)); 272 273 /* We might be trying to cast to the outermost enclosing 274 type, in which case search_struct_field won't work. */ 275 if (TYPE_NAME (real_type) != NULL 276 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1))) 277 return v; 278 279 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1); 280 if (v) 281 return v; 282 } 283 284 /* Try downcasting using information from the destination type 285 T2. This wouldn't work properly for classes with virtual 286 bases, but those were handled above. */ 287 v = search_struct_field (type_name_no_tag (t2), 288 value_zero (t1, not_lval), 0, t1, 1); 289 if (v) 290 { 291 /* Downcasting is possible (t1 is superclass of v2). */ 292 CORE_ADDR addr2 = value_address (v2); 293 294 addr2 -= value_address (v) + value_embedded_offset (v); 295 return value_at (type, addr2); 296 } 297 } 298 299 return NULL; 300 } 301 302 /* Cast one pointer or reference type to another. Both TYPE and 303 the type of ARG2 should be pointer types, or else both should be 304 reference types. If SUBCLASS_CHECK is non-zero, this will force a 305 check to see whether TYPE is a superclass of ARG2's type. If 306 SUBCLASS_CHECK is zero, then the subclass check is done only when 307 ARG2 is itself non-zero. Returns the new pointer or reference. */ 308 309 struct value * 310 value_cast_pointers (struct type *type, struct value *arg2, 311 int subclass_check) 312 { 313 struct type *type1 = check_typedef (type); 314 struct type *type2 = check_typedef (value_type (arg2)); 315 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1)); 316 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2)); 317 318 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT 319 && TYPE_CODE (t2) == TYPE_CODE_STRUCT 320 && (subclass_check || !value_logical_not (arg2))) 321 { 322 struct value *v2; 323 324 if (TYPE_CODE (type2) == TYPE_CODE_REF) 325 v2 = coerce_ref (arg2); 326 else 327 v2 = value_ind (arg2); 328 gdb_assert (TYPE_CODE (check_typedef (value_type (v2))) 329 == TYPE_CODE_STRUCT && !!"Why did coercion fail?"); 330 v2 = value_cast_structs (t1, v2); 331 /* At this point we have what we can have, un-dereference if needed. */ 332 if (v2) 333 { 334 struct value *v = value_addr (v2); 335 336 deprecated_set_value_type (v, type); 337 return v; 338 } 339 } 340 341 /* No superclass found, just change the pointer type. */ 342 arg2 = value_copy (arg2); 343 deprecated_set_value_type (arg2, type); 344 set_value_enclosing_type (arg2, type); 345 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */ 346 return arg2; 347 } 348 349 /* Cast value ARG2 to type TYPE and return as a value. 350 More general than a C cast: accepts any two types of the same length, 351 and if ARG2 is an lvalue it can be cast into anything at all. */ 352 /* In C++, casts may change pointer or object representations. */ 353 354 struct value * 355 value_cast (struct type *type, struct value *arg2) 356 { 357 enum type_code code1; 358 enum type_code code2; 359 int scalar; 360 struct type *type2; 361 362 int convert_to_boolean = 0; 363 364 if (value_type (arg2) == type) 365 return arg2; 366 367 code1 = TYPE_CODE (check_typedef (type)); 368 369 /* Check if we are casting struct reference to struct reference. */ 370 if (code1 == TYPE_CODE_REF) 371 { 372 /* We dereference type; then we recurse and finally 373 we generate value of the given reference. Nothing wrong with 374 that. */ 375 struct type *t1 = check_typedef (type); 376 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1)); 377 struct value *val = value_cast (dereftype, arg2); 378 379 return value_ref (val); 380 } 381 382 code2 = TYPE_CODE (check_typedef (value_type (arg2))); 383 384 if (code2 == TYPE_CODE_REF) 385 /* We deref the value and then do the cast. */ 386 return value_cast (type, coerce_ref (arg2)); 387 388 CHECK_TYPEDEF (type); 389 code1 = TYPE_CODE (type); 390 arg2 = coerce_ref (arg2); 391 type2 = check_typedef (value_type (arg2)); 392 393 /* You can't cast to a reference type. See value_cast_pointers 394 instead. */ 395 gdb_assert (code1 != TYPE_CODE_REF); 396 397 /* A cast to an undetermined-length array_type, such as 398 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT, 399 where N is sizeof(OBJECT)/sizeof(TYPE). */ 400 if (code1 == TYPE_CODE_ARRAY) 401 { 402 struct type *element_type = TYPE_TARGET_TYPE (type); 403 unsigned element_length = TYPE_LENGTH (check_typedef (element_type)); 404 405 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type)) 406 { 407 struct type *range_type = TYPE_INDEX_TYPE (type); 408 int val_length = TYPE_LENGTH (type2); 409 LONGEST low_bound, high_bound, new_length; 410 411 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0) 412 low_bound = 0, high_bound = 0; 413 new_length = val_length / element_length; 414 if (val_length % element_length != 0) 415 warning (_("array element type size does not " 416 "divide object size in cast")); 417 /* FIXME-type-allocation: need a way to free this type when 418 we are done with it. */ 419 range_type = create_range_type ((struct type *) NULL, 420 TYPE_TARGET_TYPE (range_type), 421 low_bound, 422 new_length + low_bound - 1); 423 deprecated_set_value_type (arg2, 424 create_array_type ((struct type *) NULL, 425 element_type, 426 range_type)); 427 return arg2; 428 } 429 } 430 431 if (current_language->c_style_arrays 432 && TYPE_CODE (type2) == TYPE_CODE_ARRAY 433 && !TYPE_VECTOR (type2)) 434 arg2 = value_coerce_array (arg2); 435 436 if (TYPE_CODE (type2) == TYPE_CODE_FUNC) 437 arg2 = value_coerce_function (arg2); 438 439 type2 = check_typedef (value_type (arg2)); 440 code2 = TYPE_CODE (type2); 441 442 if (code1 == TYPE_CODE_COMPLEX) 443 return cast_into_complex (type, arg2); 444 if (code1 == TYPE_CODE_BOOL) 445 { 446 code1 = TYPE_CODE_INT; 447 convert_to_boolean = 1; 448 } 449 if (code1 == TYPE_CODE_CHAR) 450 code1 = TYPE_CODE_INT; 451 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR) 452 code2 = TYPE_CODE_INT; 453 454 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT 455 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM 456 || code2 == TYPE_CODE_RANGE); 457 458 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION) 459 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION) 460 && TYPE_NAME (type) != 0) 461 { 462 struct value *v = value_cast_structs (type, arg2); 463 464 if (v) 465 return v; 466 } 467 468 if (code1 == TYPE_CODE_FLT && scalar) 469 return value_from_double (type, value_as_double (arg2)); 470 else if (code1 == TYPE_CODE_DECFLOAT && scalar) 471 { 472 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); 473 int dec_len = TYPE_LENGTH (type); 474 gdb_byte dec[16]; 475 476 if (code2 == TYPE_CODE_FLT) 477 decimal_from_floating (arg2, dec, dec_len, byte_order); 478 else if (code2 == TYPE_CODE_DECFLOAT) 479 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2), 480 byte_order, dec, dec_len, byte_order); 481 else 482 /* The only option left is an integral type. */ 483 decimal_from_integral (arg2, dec, dec_len, byte_order); 484 485 return value_from_decfloat (type, dec); 486 } 487 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM 488 || code1 == TYPE_CODE_RANGE) 489 && (scalar || code2 == TYPE_CODE_PTR 490 || code2 == TYPE_CODE_MEMBERPTR)) 491 { 492 LONGEST longest; 493 494 /* When we cast pointers to integers, we mustn't use 495 gdbarch_pointer_to_address to find the address the pointer 496 represents, as value_as_long would. GDB should evaluate 497 expressions just as the compiler would --- and the compiler 498 sees a cast as a simple reinterpretation of the pointer's 499 bits. */ 500 if (code2 == TYPE_CODE_PTR) 501 longest = extract_unsigned_integer 502 (value_contents (arg2), TYPE_LENGTH (type2), 503 gdbarch_byte_order (get_type_arch (type2))); 504 else 505 longest = value_as_long (arg2); 506 return value_from_longest (type, convert_to_boolean ? 507 (LONGEST) (longest ? 1 : 0) : longest); 508 } 509 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT 510 || code2 == TYPE_CODE_ENUM 511 || code2 == TYPE_CODE_RANGE)) 512 { 513 /* TYPE_LENGTH (type) is the length of a pointer, but we really 514 want the length of an address! -- we are really dealing with 515 addresses (i.e., gdb representations) not pointers (i.e., 516 target representations) here. 517 518 This allows things like "print *(int *)0x01000234" to work 519 without printing a misleading message -- which would 520 otherwise occur when dealing with a target having two byte 521 pointers and four byte addresses. */ 522 523 int addr_bit = gdbarch_addr_bit (get_type_arch (type2)); 524 LONGEST longest = value_as_long (arg2); 525 526 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT) 527 { 528 if (longest >= ((LONGEST) 1 << addr_bit) 529 || longest <= -((LONGEST) 1 << addr_bit)) 530 warning (_("value truncated")); 531 } 532 return value_from_longest (type, longest); 533 } 534 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT 535 && value_as_long (arg2) == 0) 536 { 537 struct value *result = allocate_value (type); 538 539 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0); 540 return result; 541 } 542 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT 543 && value_as_long (arg2) == 0) 544 { 545 /* The Itanium C++ ABI represents NULL pointers to members as 546 minus one, instead of biasing the normal case. */ 547 return value_from_longest (type, -1); 548 } 549 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) 550 && code2 == TYPE_CODE_ARRAY && TYPE_VECTOR (type2) 551 && TYPE_LENGTH (type) != TYPE_LENGTH (type2)) 552 error (_("Cannot convert between vector values of different sizes")); 553 else if (code1 == TYPE_CODE_ARRAY && TYPE_VECTOR (type) && scalar 554 && TYPE_LENGTH (type) != TYPE_LENGTH (type2)) 555 error (_("can only cast scalar to vector of same size")); 556 else if (code1 == TYPE_CODE_VOID) 557 { 558 return value_zero (type, not_lval); 559 } 560 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2)) 561 { 562 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR) 563 return value_cast_pointers (type, arg2, 0); 564 565 arg2 = value_copy (arg2); 566 deprecated_set_value_type (arg2, type); 567 set_value_enclosing_type (arg2, type); 568 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */ 569 return arg2; 570 } 571 else if (VALUE_LVAL (arg2) == lval_memory) 572 return value_at_lazy (type, value_address (arg2)); 573 else 574 { 575 error (_("Invalid cast.")); 576 return 0; 577 } 578 } 579 580 /* The C++ reinterpret_cast operator. */ 581 582 struct value * 583 value_reinterpret_cast (struct type *type, struct value *arg) 584 { 585 struct value *result; 586 struct type *real_type = check_typedef (type); 587 struct type *arg_type, *dest_type; 588 int is_ref = 0; 589 enum type_code dest_code, arg_code; 590 591 /* Do reference, function, and array conversion. */ 592 arg = coerce_array (arg); 593 594 /* Attempt to preserve the type the user asked for. */ 595 dest_type = type; 596 597 /* If we are casting to a reference type, transform 598 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */ 599 if (TYPE_CODE (real_type) == TYPE_CODE_REF) 600 { 601 is_ref = 1; 602 arg = value_addr (arg); 603 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type)); 604 real_type = lookup_pointer_type (real_type); 605 } 606 607 arg_type = value_type (arg); 608 609 dest_code = TYPE_CODE (real_type); 610 arg_code = TYPE_CODE (arg_type); 611 612 /* We can convert pointer types, or any pointer type to int, or int 613 type to pointer. */ 614 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT) 615 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR) 616 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT) 617 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR) 618 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT) 619 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR) 620 || (dest_code == arg_code 621 && (dest_code == TYPE_CODE_PTR 622 || dest_code == TYPE_CODE_METHODPTR 623 || dest_code == TYPE_CODE_MEMBERPTR))) 624 result = value_cast (dest_type, arg); 625 else 626 error (_("Invalid reinterpret_cast")); 627 628 if (is_ref) 629 result = value_cast (type, value_ref (value_ind (result))); 630 631 return result; 632 } 633 634 /* A helper for value_dynamic_cast. This implements the first of two 635 runtime checks: we iterate over all the base classes of the value's 636 class which are equal to the desired class; if only one of these 637 holds the value, then it is the answer. */ 638 639 static int 640 dynamic_cast_check_1 (struct type *desired_type, 641 const gdb_byte *valaddr, 642 int embedded_offset, 643 CORE_ADDR address, 644 struct value *val, 645 struct type *search_type, 646 CORE_ADDR arg_addr, 647 struct type *arg_type, 648 struct value **result) 649 { 650 int i, result_count = 0; 651 652 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i) 653 { 654 int offset = baseclass_offset (search_type, i, valaddr, embedded_offset, 655 address, val); 656 657 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i))) 658 { 659 if (address + embedded_offset + offset >= arg_addr 660 && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type)) 661 { 662 ++result_count; 663 if (!*result) 664 *result = value_at_lazy (TYPE_BASECLASS (search_type, i), 665 address + embedded_offset + offset); 666 } 667 } 668 else 669 result_count += dynamic_cast_check_1 (desired_type, 670 valaddr, 671 embedded_offset + offset, 672 address, val, 673 TYPE_BASECLASS (search_type, i), 674 arg_addr, 675 arg_type, 676 result); 677 } 678 679 return result_count; 680 } 681 682 /* A helper for value_dynamic_cast. This implements the second of two 683 runtime checks: we look for a unique public sibling class of the 684 argument's declared class. */ 685 686 static int 687 dynamic_cast_check_2 (struct type *desired_type, 688 const gdb_byte *valaddr, 689 int embedded_offset, 690 CORE_ADDR address, 691 struct value *val, 692 struct type *search_type, 693 struct value **result) 694 { 695 int i, result_count = 0; 696 697 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i) 698 { 699 int offset; 700 701 if (! BASETYPE_VIA_PUBLIC (search_type, i)) 702 continue; 703 704 offset = baseclass_offset (search_type, i, valaddr, embedded_offset, 705 address, val); 706 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i))) 707 { 708 ++result_count; 709 if (*result == NULL) 710 *result = value_at_lazy (TYPE_BASECLASS (search_type, i), 711 address + embedded_offset + offset); 712 } 713 else 714 result_count += dynamic_cast_check_2 (desired_type, 715 valaddr, 716 embedded_offset + offset, 717 address, val, 718 TYPE_BASECLASS (search_type, i), 719 result); 720 } 721 722 return result_count; 723 } 724 725 /* The C++ dynamic_cast operator. */ 726 727 struct value * 728 value_dynamic_cast (struct type *type, struct value *arg) 729 { 730 int full, top, using_enc; 731 struct type *resolved_type = check_typedef (type); 732 struct type *arg_type = check_typedef (value_type (arg)); 733 struct type *class_type, *rtti_type; 734 struct value *result, *tem, *original_arg = arg; 735 CORE_ADDR addr; 736 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF; 737 738 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR 739 && TYPE_CODE (resolved_type) != TYPE_CODE_REF) 740 error (_("Argument to dynamic_cast must be a pointer or reference type")); 741 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID 742 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS) 743 error (_("Argument to dynamic_cast must be pointer to class or `void *'")); 744 745 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type)); 746 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR) 747 { 748 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR 749 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT 750 && value_as_long (arg) == 0)) 751 error (_("Argument to dynamic_cast does not have pointer type")); 752 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR) 753 { 754 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type)); 755 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS) 756 error (_("Argument to dynamic_cast does " 757 "not have pointer to class type")); 758 } 759 760 /* Handle NULL pointers. */ 761 if (value_as_long (arg) == 0) 762 return value_zero (type, not_lval); 763 764 arg = value_ind (arg); 765 } 766 else 767 { 768 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS) 769 error (_("Argument to dynamic_cast does not have class type")); 770 } 771 772 /* If the classes are the same, just return the argument. */ 773 if (class_types_same_p (class_type, arg_type)) 774 return value_cast (type, arg); 775 776 /* If the target type is a unique base class of the argument's 777 declared type, just cast it. */ 778 if (is_ancestor (class_type, arg_type)) 779 { 780 if (is_unique_ancestor (class_type, arg)) 781 return value_cast (type, original_arg); 782 error (_("Ambiguous dynamic_cast")); 783 } 784 785 rtti_type = value_rtti_type (arg, &full, &top, &using_enc); 786 if (! rtti_type) 787 error (_("Couldn't determine value's most derived type for dynamic_cast")); 788 789 /* Compute the most derived object's address. */ 790 addr = value_address (arg); 791 if (full) 792 { 793 /* Done. */ 794 } 795 else if (using_enc) 796 addr += top; 797 else 798 addr += top + value_embedded_offset (arg); 799 800 /* dynamic_cast<void *> means to return a pointer to the 801 most-derived object. */ 802 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR 803 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID) 804 return value_at_lazy (type, addr); 805 806 tem = value_at (type, addr); 807 808 /* The first dynamic check specified in 5.2.7. */ 809 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type))) 810 { 811 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type))) 812 return tem; 813 result = NULL; 814 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type), 815 value_contents_for_printing (tem), 816 value_embedded_offset (tem), 817 value_address (tem), tem, 818 rtti_type, addr, 819 arg_type, 820 &result) == 1) 821 return value_cast (type, 822 is_ref ? value_ref (result) : value_addr (result)); 823 } 824 825 /* The second dynamic check specified in 5.2.7. */ 826 result = NULL; 827 if (is_public_ancestor (arg_type, rtti_type) 828 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type), 829 value_contents_for_printing (tem), 830 value_embedded_offset (tem), 831 value_address (tem), tem, 832 rtti_type, &result) == 1) 833 return value_cast (type, 834 is_ref ? value_ref (result) : value_addr (result)); 835 836 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR) 837 return value_zero (type, not_lval); 838 839 error (_("dynamic_cast failed")); 840 } 841 842 /* Create a value of type TYPE that is zero, and return it. */ 843 844 struct value * 845 value_zero (struct type *type, enum lval_type lv) 846 { 847 struct value *val = allocate_value (type); 848 849 VALUE_LVAL (val) = (lv == lval_computed ? not_lval : lv); 850 return val; 851 } 852 853 /* Create a not_lval value of numeric type TYPE that is one, and return it. */ 854 855 struct value * 856 value_one (struct type *type) 857 { 858 struct type *type1 = check_typedef (type); 859 struct value *val; 860 861 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT) 862 { 863 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); 864 gdb_byte v[16]; 865 866 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1"); 867 val = value_from_decfloat (type, v); 868 } 869 else if (TYPE_CODE (type1) == TYPE_CODE_FLT) 870 { 871 val = value_from_double (type, (DOUBLEST) 1); 872 } 873 else if (is_integral_type (type1)) 874 { 875 val = value_from_longest (type, (LONGEST) 1); 876 } 877 else if (TYPE_CODE (type1) == TYPE_CODE_ARRAY && TYPE_VECTOR (type1)) 878 { 879 struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1)); 880 int i; 881 LONGEST low_bound, high_bound; 882 struct value *tmp; 883 884 if (!get_array_bounds (type1, &low_bound, &high_bound)) 885 error (_("Could not determine the vector bounds")); 886 887 val = allocate_value (type); 888 for (i = 0; i < high_bound - low_bound + 1; i++) 889 { 890 tmp = value_one (eltype); 891 memcpy (value_contents_writeable (val) + i * TYPE_LENGTH (eltype), 892 value_contents_all (tmp), TYPE_LENGTH (eltype)); 893 } 894 } 895 else 896 { 897 error (_("Not a numeric type.")); 898 } 899 900 /* value_one result is never used for assignments to. */ 901 gdb_assert (VALUE_LVAL (val) == not_lval); 902 903 return val; 904 } 905 906 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */ 907 908 static struct value * 909 get_value_at (struct type *type, CORE_ADDR addr, int lazy) 910 { 911 struct value *val; 912 913 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID) 914 error (_("Attempt to dereference a generic pointer.")); 915 916 val = value_from_contents_and_address (type, NULL, addr); 917 918 if (!lazy) 919 value_fetch_lazy (val); 920 921 return val; 922 } 923 924 /* Return a value with type TYPE located at ADDR. 925 926 Call value_at only if the data needs to be fetched immediately; 927 if we can be 'lazy' and defer the fetch, perhaps indefinately, call 928 value_at_lazy instead. value_at_lazy simply records the address of 929 the data and sets the lazy-evaluation-required flag. The lazy flag 930 is tested in the value_contents macro, which is used if and when 931 the contents are actually required. 932 933 Note: value_at does *NOT* handle embedded offsets; perform such 934 adjustments before or after calling it. */ 935 936 struct value * 937 value_at (struct type *type, CORE_ADDR addr) 938 { 939 return get_value_at (type, addr, 0); 940 } 941 942 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */ 943 944 struct value * 945 value_at_lazy (struct type *type, CORE_ADDR addr) 946 { 947 return get_value_at (type, addr, 1); 948 } 949 950 /* Called only from the value_contents and value_contents_all() 951 macros, if the current data for a variable needs to be loaded into 952 value_contents(VAL). Fetches the data from the user's process, and 953 clears the lazy flag to indicate that the data in the buffer is 954 valid. 955 956 If the value is zero-length, we avoid calling read_memory, which 957 would abort. We mark the value as fetched anyway -- all 0 bytes of 958 it. 959 960 This function returns a value because it is used in the 961 value_contents macro as part of an expression, where a void would 962 not work. The value is ignored. */ 963 964 int 965 value_fetch_lazy (struct value *val) 966 { 967 gdb_assert (value_lazy (val)); 968 allocate_value_contents (val); 969 if (value_bitsize (val)) 970 { 971 /* To read a lazy bitfield, read the entire enclosing value. This 972 prevents reading the same block of (possibly volatile) memory once 973 per bitfield. It would be even better to read only the containing 974 word, but we have no way to record that just specific bits of a 975 value have been fetched. */ 976 struct type *type = check_typedef (value_type (val)); 977 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); 978 struct value *parent = value_parent (val); 979 LONGEST offset = value_offset (val); 980 LONGEST num; 981 982 if (!value_bits_valid (val, 983 TARGET_CHAR_BIT * offset + value_bitpos (val), 984 value_bitsize (val))) 985 error (_("value has been optimized out")); 986 987 if (!unpack_value_bits_as_long (value_type (val), 988 value_contents_for_printing (parent), 989 offset, 990 value_bitpos (val), 991 value_bitsize (val), parent, &num)) 992 mark_value_bytes_unavailable (val, 993 value_embedded_offset (val), 994 TYPE_LENGTH (type)); 995 else 996 store_signed_integer (value_contents_raw (val), TYPE_LENGTH (type), 997 byte_order, num); 998 } 999 else if (VALUE_LVAL (val) == lval_memory) 1000 { 1001 CORE_ADDR addr = value_address (val); 1002 struct type *type = check_typedef (value_enclosing_type (val)); 1003 1004 if (TYPE_LENGTH (type)) 1005 read_value_memory (val, 0, value_stack (val), 1006 addr, value_contents_all_raw (val), 1007 TYPE_LENGTH (type)); 1008 } 1009 else if (VALUE_LVAL (val) == lval_register) 1010 { 1011 struct frame_info *frame; 1012 int regnum; 1013 struct type *type = check_typedef (value_type (val)); 1014 struct value *new_val = val, *mark = value_mark (); 1015 1016 /* Offsets are not supported here; lazy register values must 1017 refer to the entire register. */ 1018 gdb_assert (value_offset (val) == 0); 1019 1020 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val)) 1021 { 1022 frame = frame_find_by_id (VALUE_FRAME_ID (new_val)); 1023 regnum = VALUE_REGNUM (new_val); 1024 1025 gdb_assert (frame != NULL); 1026 1027 /* Convertible register routines are used for multi-register 1028 values and for interpretation in different types 1029 (e.g. float or int from a double register). Lazy 1030 register values should have the register's natural type, 1031 so they do not apply. */ 1032 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame), 1033 regnum, type)); 1034 1035 new_val = get_frame_register_value (frame, regnum); 1036 } 1037 1038 /* If it's still lazy (for instance, a saved register on the 1039 stack), fetch it. */ 1040 if (value_lazy (new_val)) 1041 value_fetch_lazy (new_val); 1042 1043 /* If the register was not saved, mark it optimized out. */ 1044 if (value_optimized_out (new_val)) 1045 set_value_optimized_out (val, 1); 1046 else 1047 { 1048 set_value_lazy (val, 0); 1049 value_contents_copy (val, value_embedded_offset (val), 1050 new_val, value_embedded_offset (new_val), 1051 TYPE_LENGTH (type)); 1052 } 1053 1054 if (frame_debug) 1055 { 1056 struct gdbarch *gdbarch; 1057 frame = frame_find_by_id (VALUE_FRAME_ID (val)); 1058 regnum = VALUE_REGNUM (val); 1059 gdbarch = get_frame_arch (frame); 1060 1061 fprintf_unfiltered (gdb_stdlog, 1062 "{ value_fetch_lazy " 1063 "(frame=%d,regnum=%d(%s),...) ", 1064 frame_relative_level (frame), regnum, 1065 user_reg_map_regnum_to_name (gdbarch, regnum)); 1066 1067 fprintf_unfiltered (gdb_stdlog, "->"); 1068 if (value_optimized_out (new_val)) 1069 fprintf_unfiltered (gdb_stdlog, " optimized out"); 1070 else 1071 { 1072 int i; 1073 const gdb_byte *buf = value_contents (new_val); 1074 1075 if (VALUE_LVAL (new_val) == lval_register) 1076 fprintf_unfiltered (gdb_stdlog, " register=%d", 1077 VALUE_REGNUM (new_val)); 1078 else if (VALUE_LVAL (new_val) == lval_memory) 1079 fprintf_unfiltered (gdb_stdlog, " address=%s", 1080 paddress (gdbarch, 1081 value_address (new_val))); 1082 else 1083 fprintf_unfiltered (gdb_stdlog, " computed"); 1084 1085 fprintf_unfiltered (gdb_stdlog, " bytes="); 1086 fprintf_unfiltered (gdb_stdlog, "["); 1087 for (i = 0; i < register_size (gdbarch, regnum); i++) 1088 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]); 1089 fprintf_unfiltered (gdb_stdlog, "]"); 1090 } 1091 1092 fprintf_unfiltered (gdb_stdlog, " }\n"); 1093 } 1094 1095 /* Dispose of the intermediate values. This prevents 1096 watchpoints from trying to watch the saved frame pointer. */ 1097 value_free_to_mark (mark); 1098 } 1099 else if (VALUE_LVAL (val) == lval_computed 1100 && value_computed_funcs (val)->read != NULL) 1101 value_computed_funcs (val)->read (val); 1102 else if (value_optimized_out (val)) 1103 /* Keep it optimized out. */; 1104 else 1105 internal_error (__FILE__, __LINE__, _("Unexpected lazy value type.")); 1106 1107 set_value_lazy (val, 0); 1108 return 0; 1109 } 1110 1111 void 1112 read_value_memory (struct value *val, int embedded_offset, 1113 int stack, CORE_ADDR memaddr, 1114 gdb_byte *buffer, size_t length) 1115 { 1116 if (length) 1117 { 1118 VEC(mem_range_s) *available_memory; 1119 1120 if (get_traceframe_number () < 0 1121 || !traceframe_available_memory (&available_memory, memaddr, length)) 1122 { 1123 if (stack) 1124 read_stack (memaddr, buffer, length); 1125 else 1126 read_memory (memaddr, buffer, length); 1127 } 1128 else 1129 { 1130 struct target_section_table *table; 1131 struct cleanup *old_chain; 1132 CORE_ADDR unavail; 1133 mem_range_s *r; 1134 int i; 1135 1136 /* Fallback to reading from read-only sections. */ 1137 table = target_get_section_table (&exec_ops); 1138 available_memory = 1139 section_table_available_memory (available_memory, 1140 memaddr, length, 1141 table->sections, 1142 table->sections_end); 1143 1144 old_chain = make_cleanup (VEC_cleanup(mem_range_s), 1145 &available_memory); 1146 1147 normalize_mem_ranges (available_memory); 1148 1149 /* Mark which bytes are unavailable, and read those which 1150 are available. */ 1151 1152 unavail = memaddr; 1153 1154 for (i = 0; 1155 VEC_iterate (mem_range_s, available_memory, i, r); 1156 i++) 1157 { 1158 if (mem_ranges_overlap (r->start, r->length, 1159 memaddr, length)) 1160 { 1161 CORE_ADDR lo1, hi1, lo2, hi2; 1162 CORE_ADDR start, end; 1163 1164 /* Get the intersection window. */ 1165 lo1 = memaddr; 1166 hi1 = memaddr + length; 1167 lo2 = r->start; 1168 hi2 = r->start + r->length; 1169 start = max (lo1, lo2); 1170 end = min (hi1, hi2); 1171 1172 gdb_assert (end - memaddr <= length); 1173 1174 if (start > unavail) 1175 mark_value_bytes_unavailable (val, 1176 (embedded_offset 1177 + unavail - memaddr), 1178 start - unavail); 1179 unavail = end; 1180 1181 read_memory (start, buffer + start - memaddr, end - start); 1182 } 1183 } 1184 1185 if (unavail != memaddr + length) 1186 mark_value_bytes_unavailable (val, 1187 embedded_offset + unavail - memaddr, 1188 (memaddr + length) - unavail); 1189 1190 do_cleanups (old_chain); 1191 } 1192 } 1193 } 1194 1195 /* Store the contents of FROMVAL into the location of TOVAL. 1196 Return a new value with the location of TOVAL and contents of FROMVAL. */ 1197 1198 struct value * 1199 value_assign (struct value *toval, struct value *fromval) 1200 { 1201 struct type *type; 1202 struct value *val; 1203 struct frame_id old_frame; 1204 1205 if (!deprecated_value_modifiable (toval)) 1206 error (_("Left operand of assignment is not a modifiable lvalue.")); 1207 1208 toval = coerce_ref (toval); 1209 1210 type = value_type (toval); 1211 if (VALUE_LVAL (toval) != lval_internalvar) 1212 fromval = value_cast (type, fromval); 1213 else 1214 { 1215 /* Coerce arrays and functions to pointers, except for arrays 1216 which only live in GDB's storage. */ 1217 if (!value_must_coerce_to_target (fromval)) 1218 fromval = coerce_array (fromval); 1219 } 1220 1221 CHECK_TYPEDEF (type); 1222 1223 /* Since modifying a register can trash the frame chain, and 1224 modifying memory can trash the frame cache, we save the old frame 1225 and then restore the new frame afterwards. */ 1226 old_frame = get_frame_id (deprecated_safe_get_selected_frame ()); 1227 1228 switch (VALUE_LVAL (toval)) 1229 { 1230 case lval_internalvar: 1231 set_internalvar (VALUE_INTERNALVAR (toval), fromval); 1232 return value_of_internalvar (get_type_arch (type), 1233 VALUE_INTERNALVAR (toval)); 1234 1235 case lval_internalvar_component: 1236 { 1237 int offset = value_offset (toval); 1238 1239 /* Are we dealing with a bitfield? 1240 1241 It is important to mention that `value_parent (toval)' is 1242 non-NULL iff `value_bitsize (toval)' is non-zero. */ 1243 if (value_bitsize (toval)) 1244 { 1245 /* VALUE_INTERNALVAR below refers to the parent value, while 1246 the offset is relative to this parent value. */ 1247 gdb_assert (value_parent (value_parent (toval)) == NULL); 1248 offset += value_offset (value_parent (toval)); 1249 } 1250 1251 set_internalvar_component (VALUE_INTERNALVAR (toval), 1252 offset, 1253 value_bitpos (toval), 1254 value_bitsize (toval), 1255 fromval); 1256 } 1257 break; 1258 1259 case lval_memory: 1260 { 1261 const gdb_byte *dest_buffer; 1262 CORE_ADDR changed_addr; 1263 int changed_len; 1264 gdb_byte buffer[sizeof (LONGEST)]; 1265 1266 if (value_bitsize (toval)) 1267 { 1268 struct value *parent = value_parent (toval); 1269 1270 changed_addr = value_address (parent) + value_offset (toval); 1271 changed_len = (value_bitpos (toval) 1272 + value_bitsize (toval) 1273 + HOST_CHAR_BIT - 1) 1274 / HOST_CHAR_BIT; 1275 1276 /* If we can read-modify-write exactly the size of the 1277 containing type (e.g. short or int) then do so. This 1278 is safer for volatile bitfields mapped to hardware 1279 registers. */ 1280 if (changed_len < TYPE_LENGTH (type) 1281 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST) 1282 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0) 1283 changed_len = TYPE_LENGTH (type); 1284 1285 if (changed_len > (int) sizeof (LONGEST)) 1286 error (_("Can't handle bitfields which " 1287 "don't fit in a %d bit word."), 1288 (int) sizeof (LONGEST) * HOST_CHAR_BIT); 1289 1290 read_memory (changed_addr, buffer, changed_len); 1291 modify_field (type, buffer, value_as_long (fromval), 1292 value_bitpos (toval), value_bitsize (toval)); 1293 dest_buffer = buffer; 1294 } 1295 else 1296 { 1297 changed_addr = value_address (toval); 1298 changed_len = TYPE_LENGTH (type); 1299 dest_buffer = value_contents (fromval); 1300 } 1301 1302 write_memory_with_notification (changed_addr, dest_buffer, changed_len); 1303 } 1304 break; 1305 1306 case lval_register: 1307 { 1308 struct frame_info *frame; 1309 struct gdbarch *gdbarch; 1310 int value_reg; 1311 1312 /* Figure out which frame this is in currently. */ 1313 frame = frame_find_by_id (VALUE_FRAME_ID (toval)); 1314 value_reg = VALUE_REGNUM (toval); 1315 1316 if (!frame) 1317 error (_("Value being assigned to is no longer active.")); 1318 1319 gdbarch = get_frame_arch (frame); 1320 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type)) 1321 { 1322 /* If TOVAL is a special machine register requiring 1323 conversion of program values to a special raw 1324 format. */ 1325 gdbarch_value_to_register (gdbarch, frame, 1326 VALUE_REGNUM (toval), type, 1327 value_contents (fromval)); 1328 } 1329 else 1330 { 1331 if (value_bitsize (toval)) 1332 { 1333 struct value *parent = value_parent (toval); 1334 int offset = value_offset (parent) + value_offset (toval); 1335 int changed_len; 1336 gdb_byte buffer[sizeof (LONGEST)]; 1337 int optim, unavail; 1338 1339 changed_len = (value_bitpos (toval) 1340 + value_bitsize (toval) 1341 + HOST_CHAR_BIT - 1) 1342 / HOST_CHAR_BIT; 1343 1344 if (changed_len > (int) sizeof (LONGEST)) 1345 error (_("Can't handle bitfields which " 1346 "don't fit in a %d bit word."), 1347 (int) sizeof (LONGEST) * HOST_CHAR_BIT); 1348 1349 if (!get_frame_register_bytes (frame, value_reg, offset, 1350 changed_len, buffer, 1351 &optim, &unavail)) 1352 { 1353 if (optim) 1354 error (_("value has been optimized out")); 1355 if (unavail) 1356 throw_error (NOT_AVAILABLE_ERROR, 1357 _("value is not available")); 1358 } 1359 1360 modify_field (type, buffer, value_as_long (fromval), 1361 value_bitpos (toval), value_bitsize (toval)); 1362 1363 put_frame_register_bytes (frame, value_reg, offset, 1364 changed_len, buffer); 1365 } 1366 else 1367 { 1368 put_frame_register_bytes (frame, value_reg, 1369 value_offset (toval), 1370 TYPE_LENGTH (type), 1371 value_contents (fromval)); 1372 } 1373 } 1374 1375 if (deprecated_register_changed_hook) 1376 deprecated_register_changed_hook (-1); 1377 break; 1378 } 1379 1380 case lval_computed: 1381 { 1382 const struct lval_funcs *funcs = value_computed_funcs (toval); 1383 1384 if (funcs->write != NULL) 1385 { 1386 funcs->write (toval, fromval); 1387 break; 1388 } 1389 } 1390 /* Fall through. */ 1391 1392 default: 1393 error (_("Left operand of assignment is not an lvalue.")); 1394 } 1395 1396 /* Assigning to the stack pointer, frame pointer, and other 1397 (architecture and calling convention specific) registers may 1398 cause the frame cache and regcache to be out of date. Assigning to memory 1399 also can. We just do this on all assignments to registers or 1400 memory, for simplicity's sake; I doubt the slowdown matters. */ 1401 switch (VALUE_LVAL (toval)) 1402 { 1403 case lval_memory: 1404 case lval_register: 1405 case lval_computed: 1406 1407 observer_notify_target_changed (¤t_target); 1408 1409 /* Having destroyed the frame cache, restore the selected 1410 frame. */ 1411 1412 /* FIXME: cagney/2002-11-02: There has to be a better way of 1413 doing this. Instead of constantly saving/restoring the 1414 frame. Why not create a get_selected_frame() function that, 1415 having saved the selected frame's ID can automatically 1416 re-find the previously selected frame automatically. */ 1417 1418 { 1419 struct frame_info *fi = frame_find_by_id (old_frame); 1420 1421 if (fi != NULL) 1422 select_frame (fi); 1423 } 1424 1425 break; 1426 default: 1427 break; 1428 } 1429 1430 /* If the field does not entirely fill a LONGEST, then zero the sign 1431 bits. If the field is signed, and is negative, then sign 1432 extend. */ 1433 if ((value_bitsize (toval) > 0) 1434 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST))) 1435 { 1436 LONGEST fieldval = value_as_long (fromval); 1437 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1; 1438 1439 fieldval &= valmask; 1440 if (!TYPE_UNSIGNED (type) 1441 && (fieldval & (valmask ^ (valmask >> 1)))) 1442 fieldval |= ~valmask; 1443 1444 fromval = value_from_longest (type, fieldval); 1445 } 1446 1447 /* The return value is a copy of TOVAL so it shares its location 1448 information, but its contents are updated from FROMVAL. This 1449 implies the returned value is not lazy, even if TOVAL was. */ 1450 val = value_copy (toval); 1451 set_value_lazy (val, 0); 1452 memcpy (value_contents_raw (val), value_contents (fromval), 1453 TYPE_LENGTH (type)); 1454 1455 /* We copy over the enclosing type and pointed-to offset from FROMVAL 1456 in the case of pointer types. For object types, the enclosing type 1457 and embedded offset must *not* be copied: the target object refered 1458 to by TOVAL retains its original dynamic type after assignment. */ 1459 if (TYPE_CODE (type) == TYPE_CODE_PTR) 1460 { 1461 set_value_enclosing_type (val, value_enclosing_type (fromval)); 1462 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval)); 1463 } 1464 1465 return val; 1466 } 1467 1468 /* Extend a value VAL to COUNT repetitions of its type. */ 1469 1470 struct value * 1471 value_repeat (struct value *arg1, int count) 1472 { 1473 struct value *val; 1474 1475 if (VALUE_LVAL (arg1) != lval_memory) 1476 error (_("Only values in memory can be extended with '@'.")); 1477 if (count < 1) 1478 error (_("Invalid number %d of repetitions."), count); 1479 1480 val = allocate_repeat_value (value_enclosing_type (arg1), count); 1481 1482 VALUE_LVAL (val) = lval_memory; 1483 set_value_address (val, value_address (arg1)); 1484 1485 read_value_memory (val, 0, value_stack (val), value_address (val), 1486 value_contents_all_raw (val), 1487 TYPE_LENGTH (value_enclosing_type (val))); 1488 1489 return val; 1490 } 1491 1492 struct value * 1493 value_of_variable (struct symbol *var, const struct block *b) 1494 { 1495 struct frame_info *frame; 1496 1497 if (!symbol_read_needs_frame (var)) 1498 frame = NULL; 1499 else if (!b) 1500 frame = get_selected_frame (_("No frame selected.")); 1501 else 1502 { 1503 frame = block_innermost_frame (b); 1504 if (!frame) 1505 { 1506 if (BLOCK_FUNCTION (b) && !block_inlined_p (b) 1507 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b))) 1508 error (_("No frame is currently executing in block %s."), 1509 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b))); 1510 else 1511 error (_("No frame is currently executing in specified block")); 1512 } 1513 } 1514 1515 return read_var_value (var, frame); 1516 } 1517 1518 struct value * 1519 address_of_variable (struct symbol *var, const struct block *b) 1520 { 1521 struct type *type = SYMBOL_TYPE (var); 1522 struct value *val; 1523 1524 /* Evaluate it first; if the result is a memory address, we're fine. 1525 Lazy evaluation pays off here. */ 1526 1527 val = value_of_variable (var, b); 1528 1529 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val)) 1530 || TYPE_CODE (type) == TYPE_CODE_FUNC) 1531 { 1532 CORE_ADDR addr = value_address (val); 1533 1534 return value_from_pointer (lookup_pointer_type (type), addr); 1535 } 1536 1537 /* Not a memory address; check what the problem was. */ 1538 switch (VALUE_LVAL (val)) 1539 { 1540 case lval_register: 1541 { 1542 struct frame_info *frame; 1543 const char *regname; 1544 1545 frame = frame_find_by_id (VALUE_FRAME_ID (val)); 1546 gdb_assert (frame); 1547 1548 regname = gdbarch_register_name (get_frame_arch (frame), 1549 VALUE_REGNUM (val)); 1550 gdb_assert (regname && *regname); 1551 1552 error (_("Address requested for identifier " 1553 "\"%s\" which is in register $%s"), 1554 SYMBOL_PRINT_NAME (var), regname); 1555 break; 1556 } 1557 1558 default: 1559 error (_("Can't take address of \"%s\" which isn't an lvalue."), 1560 SYMBOL_PRINT_NAME (var)); 1561 break; 1562 } 1563 1564 return val; 1565 } 1566 1567 /* Return one if VAL does not live in target memory, but should in order 1568 to operate on it. Otherwise return zero. */ 1569 1570 int 1571 value_must_coerce_to_target (struct value *val) 1572 { 1573 struct type *valtype; 1574 1575 /* The only lval kinds which do not live in target memory. */ 1576 if (VALUE_LVAL (val) != not_lval 1577 && VALUE_LVAL (val) != lval_internalvar) 1578 return 0; 1579 1580 valtype = check_typedef (value_type (val)); 1581 1582 switch (TYPE_CODE (valtype)) 1583 { 1584 case TYPE_CODE_ARRAY: 1585 return TYPE_VECTOR (valtype) ? 0 : 1; 1586 case TYPE_CODE_STRING: 1587 return 1; 1588 default: 1589 return 0; 1590 } 1591 } 1592 1593 /* Make sure that VAL lives in target memory if it's supposed to. For 1594 instance, strings are constructed as character arrays in GDB's 1595 storage, and this function copies them to the target. */ 1596 1597 struct value * 1598 value_coerce_to_target (struct value *val) 1599 { 1600 LONGEST length; 1601 CORE_ADDR addr; 1602 1603 if (!value_must_coerce_to_target (val)) 1604 return val; 1605 1606 length = TYPE_LENGTH (check_typedef (value_type (val))); 1607 addr = allocate_space_in_inferior (length); 1608 write_memory (addr, value_contents (val), length); 1609 return value_at_lazy (value_type (val), addr); 1610 } 1611 1612 /* Given a value which is an array, return a value which is a pointer 1613 to its first element, regardless of whether or not the array has a 1614 nonzero lower bound. 1615 1616 FIXME: A previous comment here indicated that this routine should 1617 be substracting the array's lower bound. It's not clear to me that 1618 this is correct. Given an array subscripting operation, it would 1619 certainly work to do the adjustment here, essentially computing: 1620 1621 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0]) 1622 1623 However I believe a more appropriate and logical place to account 1624 for the lower bound is to do so in value_subscript, essentially 1625 computing: 1626 1627 (&array[0] + ((index - lowerbound) * sizeof array[0])) 1628 1629 As further evidence consider what would happen with operations 1630 other than array subscripting, where the caller would get back a 1631 value that had an address somewhere before the actual first element 1632 of the array, and the information about the lower bound would be 1633 lost because of the coercion to pointer type. */ 1634 1635 struct value * 1636 value_coerce_array (struct value *arg1) 1637 { 1638 struct type *type = check_typedef (value_type (arg1)); 1639 1640 /* If the user tries to do something requiring a pointer with an 1641 array that has not yet been pushed to the target, then this would 1642 be a good time to do so. */ 1643 arg1 = value_coerce_to_target (arg1); 1644 1645 if (VALUE_LVAL (arg1) != lval_memory) 1646 error (_("Attempt to take address of value not located in memory.")); 1647 1648 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)), 1649 value_address (arg1)); 1650 } 1651 1652 /* Given a value which is a function, return a value which is a pointer 1653 to it. */ 1654 1655 struct value * 1656 value_coerce_function (struct value *arg1) 1657 { 1658 struct value *retval; 1659 1660 if (VALUE_LVAL (arg1) != lval_memory) 1661 error (_("Attempt to take address of value not located in memory.")); 1662 1663 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)), 1664 value_address (arg1)); 1665 return retval; 1666 } 1667 1668 /* Return a pointer value for the object for which ARG1 is the 1669 contents. */ 1670 1671 struct value * 1672 value_addr (struct value *arg1) 1673 { 1674 struct value *arg2; 1675 struct type *type = check_typedef (value_type (arg1)); 1676 1677 if (TYPE_CODE (type) == TYPE_CODE_REF) 1678 { 1679 /* Copy the value, but change the type from (T&) to (T*). We 1680 keep the same location information, which is efficient, and 1681 allows &(&X) to get the location containing the reference. */ 1682 arg2 = value_copy (arg1); 1683 deprecated_set_value_type (arg2, 1684 lookup_pointer_type (TYPE_TARGET_TYPE (type))); 1685 return arg2; 1686 } 1687 if (TYPE_CODE (type) == TYPE_CODE_FUNC) 1688 return value_coerce_function (arg1); 1689 1690 /* If this is an array that has not yet been pushed to the target, 1691 then this would be a good time to force it to memory. */ 1692 arg1 = value_coerce_to_target (arg1); 1693 1694 if (VALUE_LVAL (arg1) != lval_memory) 1695 error (_("Attempt to take address of value not located in memory.")); 1696 1697 /* Get target memory address. */ 1698 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)), 1699 (value_address (arg1) 1700 + value_embedded_offset (arg1))); 1701 1702 /* This may be a pointer to a base subobject; so remember the 1703 full derived object's type ... */ 1704 set_value_enclosing_type (arg2, 1705 lookup_pointer_type (value_enclosing_type (arg1))); 1706 /* ... and also the relative position of the subobject in the full 1707 object. */ 1708 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1)); 1709 return arg2; 1710 } 1711 1712 /* Return a reference value for the object for which ARG1 is the 1713 contents. */ 1714 1715 struct value * 1716 value_ref (struct value *arg1) 1717 { 1718 struct value *arg2; 1719 struct type *type = check_typedef (value_type (arg1)); 1720 1721 if (TYPE_CODE (type) == TYPE_CODE_REF) 1722 return arg1; 1723 1724 arg2 = value_addr (arg1); 1725 deprecated_set_value_type (arg2, lookup_reference_type (type)); 1726 return arg2; 1727 } 1728 1729 /* Given a value of a pointer type, apply the C unary * operator to 1730 it. */ 1731 1732 struct value * 1733 value_ind (struct value *arg1) 1734 { 1735 struct type *base_type; 1736 struct value *arg2; 1737 1738 arg1 = coerce_array (arg1); 1739 1740 base_type = check_typedef (value_type (arg1)); 1741 1742 if (VALUE_LVAL (arg1) == lval_computed) 1743 { 1744 const struct lval_funcs *funcs = value_computed_funcs (arg1); 1745 1746 if (funcs->indirect) 1747 { 1748 struct value *result = funcs->indirect (arg1); 1749 1750 if (result) 1751 return result; 1752 } 1753 } 1754 1755 if (TYPE_CODE (base_type) == TYPE_CODE_PTR) 1756 { 1757 struct type *enc_type; 1758 1759 /* We may be pointing to something embedded in a larger object. 1760 Get the real type of the enclosing object. */ 1761 enc_type = check_typedef (value_enclosing_type (arg1)); 1762 enc_type = TYPE_TARGET_TYPE (enc_type); 1763 1764 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC 1765 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD) 1766 /* For functions, go through find_function_addr, which knows 1767 how to handle function descriptors. */ 1768 arg2 = value_at_lazy (enc_type, 1769 find_function_addr (arg1, NULL)); 1770 else 1771 /* Retrieve the enclosing object pointed to. */ 1772 arg2 = value_at_lazy (enc_type, 1773 (value_as_address (arg1) 1774 - value_pointed_to_offset (arg1))); 1775 1776 return readjust_indirect_value_type (arg2, enc_type, base_type, arg1); 1777 } 1778 1779 error (_("Attempt to take contents of a non-pointer value.")); 1780 return 0; /* For lint -- never reached. */ 1781 } 1782 1783 /* Create a value for an array by allocating space in GDB, copying the 1784 data into that space, and then setting up an array value. 1785 1786 The array bounds are set from LOWBOUND and HIGHBOUND, and the array 1787 is populated from the values passed in ELEMVEC. 1788 1789 The element type of the array is inherited from the type of the 1790 first element, and all elements must have the same size (though we 1791 don't currently enforce any restriction on their types). */ 1792 1793 struct value * 1794 value_array (int lowbound, int highbound, struct value **elemvec) 1795 { 1796 int nelem; 1797 int idx; 1798 unsigned int typelength; 1799 struct value *val; 1800 struct type *arraytype; 1801 1802 /* Validate that the bounds are reasonable and that each of the 1803 elements have the same size. */ 1804 1805 nelem = highbound - lowbound + 1; 1806 if (nelem <= 0) 1807 { 1808 error (_("bad array bounds (%d, %d)"), lowbound, highbound); 1809 } 1810 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0])); 1811 for (idx = 1; idx < nelem; idx++) 1812 { 1813 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength) 1814 { 1815 error (_("array elements must all be the same size")); 1816 } 1817 } 1818 1819 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]), 1820 lowbound, highbound); 1821 1822 if (!current_language->c_style_arrays) 1823 { 1824 val = allocate_value (arraytype); 1825 for (idx = 0; idx < nelem; idx++) 1826 value_contents_copy (val, idx * typelength, elemvec[idx], 0, 1827 typelength); 1828 return val; 1829 } 1830 1831 /* Allocate space to store the array, and then initialize it by 1832 copying in each element. */ 1833 1834 val = allocate_value (arraytype); 1835 for (idx = 0; idx < nelem; idx++) 1836 value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength); 1837 return val; 1838 } 1839 1840 struct value * 1841 value_cstring (char *ptr, ssize_t len, struct type *char_type) 1842 { 1843 struct value *val; 1844 int lowbound = current_language->string_lower_bound; 1845 ssize_t highbound = len / TYPE_LENGTH (char_type); 1846 struct type *stringtype 1847 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1); 1848 1849 val = allocate_value (stringtype); 1850 memcpy (value_contents_raw (val), ptr, len); 1851 return val; 1852 } 1853 1854 /* Create a value for a string constant by allocating space in the 1855 inferior, copying the data into that space, and returning the 1856 address with type TYPE_CODE_STRING. PTR points to the string 1857 constant data; LEN is number of characters. 1858 1859 Note that string types are like array of char types with a lower 1860 bound of zero and an upper bound of LEN - 1. Also note that the 1861 string may contain embedded null bytes. */ 1862 1863 struct value * 1864 value_string (char *ptr, ssize_t len, struct type *char_type) 1865 { 1866 struct value *val; 1867 int lowbound = current_language->string_lower_bound; 1868 ssize_t highbound = len / TYPE_LENGTH (char_type); 1869 struct type *stringtype 1870 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1); 1871 1872 val = allocate_value (stringtype); 1873 memcpy (value_contents_raw (val), ptr, len); 1874 return val; 1875 } 1876 1877 1878 /* See if we can pass arguments in T2 to a function which takes 1879 arguments of types T1. T1 is a list of NARGS arguments, and T2 is 1880 a NULL-terminated vector. If some arguments need coercion of some 1881 sort, then the coerced values are written into T2. Return value is 1882 0 if the arguments could be matched, or the position at which they 1883 differ if not. 1884 1885 STATICP is nonzero if the T1 argument list came from a static 1886 member function. T2 will still include the ``this'' pointer, but 1887 it will be skipped. 1888 1889 For non-static member functions, we ignore the first argument, 1890 which is the type of the instance variable. This is because we 1891 want to handle calls with objects from derived classes. This is 1892 not entirely correct: we should actually check to make sure that a 1893 requested operation is type secure, shouldn't we? FIXME. */ 1894 1895 static int 1896 typecmp (int staticp, int varargs, int nargs, 1897 struct field t1[], struct value *t2[]) 1898 { 1899 int i; 1900 1901 if (t2 == 0) 1902 internal_error (__FILE__, __LINE__, 1903 _("typecmp: no argument list")); 1904 1905 /* Skip ``this'' argument if applicable. T2 will always include 1906 THIS. */ 1907 if (staticp) 1908 t2 ++; 1909 1910 for (i = 0; 1911 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID; 1912 i++) 1913 { 1914 struct type *tt1, *tt2; 1915 1916 if (!t2[i]) 1917 return i + 1; 1918 1919 tt1 = check_typedef (t1[i].type); 1920 tt2 = check_typedef (value_type (t2[i])); 1921 1922 if (TYPE_CODE (tt1) == TYPE_CODE_REF 1923 /* We should be doing hairy argument matching, as below. */ 1924 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) 1925 == TYPE_CODE (tt2))) 1926 { 1927 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY) 1928 t2[i] = value_coerce_array (t2[i]); 1929 else 1930 t2[i] = value_ref (t2[i]); 1931 continue; 1932 } 1933 1934 /* djb - 20000715 - Until the new type structure is in the 1935 place, and we can attempt things like implicit conversions, 1936 we need to do this so you can take something like a map<const 1937 char *>, and properly access map["hello"], because the 1938 argument to [] will be a reference to a pointer to a char, 1939 and the argument will be a pointer to a char. */ 1940 while (TYPE_CODE(tt1) == TYPE_CODE_REF 1941 || TYPE_CODE (tt1) == TYPE_CODE_PTR) 1942 { 1943 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) ); 1944 } 1945 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY 1946 || TYPE_CODE(tt2) == TYPE_CODE_PTR 1947 || TYPE_CODE(tt2) == TYPE_CODE_REF) 1948 { 1949 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2)); 1950 } 1951 if (TYPE_CODE (tt1) == TYPE_CODE (tt2)) 1952 continue; 1953 /* Array to pointer is a `trivial conversion' according to the 1954 ARM. */ 1955 1956 /* We should be doing much hairier argument matching (see 1957 section 13.2 of the ARM), but as a quick kludge, just check 1958 for the same type code. */ 1959 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i]))) 1960 return i + 1; 1961 } 1962 if (varargs || t2[i] == NULL) 1963 return 0; 1964 return i + 1; 1965 } 1966 1967 /* Helper class for do_search_struct_field that updates *RESULT_PTR 1968 and *LAST_BOFFSET, and possibly throws an exception if the field 1969 search has yielded ambiguous results. */ 1970 1971 static void 1972 update_search_result (struct value **result_ptr, struct value *v, 1973 int *last_boffset, int boffset, 1974 const char *name, struct type *type) 1975 { 1976 if (v != NULL) 1977 { 1978 if (*result_ptr != NULL 1979 /* The result is not ambiguous if all the classes that are 1980 found occupy the same space. */ 1981 && *last_boffset != boffset) 1982 error (_("base class '%s' is ambiguous in type '%s'"), 1983 name, TYPE_SAFE_NAME (type)); 1984 *result_ptr = v; 1985 *last_boffset = boffset; 1986 } 1987 } 1988 1989 /* A helper for search_struct_field. This does all the work; most 1990 arguments are as passed to search_struct_field. The result is 1991 stored in *RESULT_PTR, which must be initialized to NULL. 1992 OUTERMOST_TYPE is the type of the initial type passed to 1993 search_struct_field; this is used for error reporting when the 1994 lookup is ambiguous. */ 1995 1996 static void 1997 do_search_struct_field (const char *name, struct value *arg1, int offset, 1998 struct type *type, int looking_for_baseclass, 1999 struct value **result_ptr, 2000 int *last_boffset, 2001 struct type *outermost_type) 2002 { 2003 int i; 2004 int nbases; 2005 2006 CHECK_TYPEDEF (type); 2007 nbases = TYPE_N_BASECLASSES (type); 2008 2009 if (!looking_for_baseclass) 2010 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--) 2011 { 2012 const char *t_field_name = TYPE_FIELD_NAME (type, i); 2013 2014 if (t_field_name && (strcmp_iw (t_field_name, name) == 0)) 2015 { 2016 struct value *v; 2017 2018 if (field_is_static (&TYPE_FIELD (type, i))) 2019 { 2020 v = value_static_field (type, i); 2021 if (v == 0) 2022 error (_("field %s is nonexistent or " 2023 "has been optimized out"), 2024 name); 2025 } 2026 else 2027 v = value_primitive_field (arg1, offset, i, type); 2028 *result_ptr = v; 2029 return; 2030 } 2031 2032 if (t_field_name 2033 && (t_field_name[0] == '\0' 2034 || (TYPE_CODE (type) == TYPE_CODE_UNION 2035 && (strcmp_iw (t_field_name, "else") == 0)))) 2036 { 2037 struct type *field_type = TYPE_FIELD_TYPE (type, i); 2038 2039 if (TYPE_CODE (field_type) == TYPE_CODE_UNION 2040 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT) 2041 { 2042 /* Look for a match through the fields of an anonymous 2043 union, or anonymous struct. C++ provides anonymous 2044 unions. 2045 2046 In the GNU Chill (now deleted from GDB) 2047 implementation of variant record types, each 2048 <alternative field> has an (anonymous) union type, 2049 each member of the union represents a <variant 2050 alternative>. Each <variant alternative> is 2051 represented as a struct, with a member for each 2052 <variant field>. */ 2053 2054 struct value *v = NULL; 2055 int new_offset = offset; 2056 2057 /* This is pretty gross. In G++, the offset in an 2058 anonymous union is relative to the beginning of the 2059 enclosing struct. In the GNU Chill (now deleted 2060 from GDB) implementation of variant records, the 2061 bitpos is zero in an anonymous union field, so we 2062 have to add the offset of the union here. */ 2063 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT 2064 || (TYPE_NFIELDS (field_type) > 0 2065 && TYPE_FIELD_BITPOS (field_type, 0) == 0)) 2066 new_offset += TYPE_FIELD_BITPOS (type, i) / 8; 2067 2068 do_search_struct_field (name, arg1, new_offset, 2069 field_type, 2070 looking_for_baseclass, &v, 2071 last_boffset, 2072 outermost_type); 2073 if (v) 2074 { 2075 *result_ptr = v; 2076 return; 2077 } 2078 } 2079 } 2080 } 2081 2082 for (i = 0; i < nbases; i++) 2083 { 2084 struct value *v = NULL; 2085 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i)); 2086 /* If we are looking for baseclasses, this is what we get when 2087 we hit them. But it could happen that the base part's member 2088 name is not yet filled in. */ 2089 int found_baseclass = (looking_for_baseclass 2090 && TYPE_BASECLASS_NAME (type, i) != NULL 2091 && (strcmp_iw (name, 2092 TYPE_BASECLASS_NAME (type, 2093 i)) == 0)); 2094 int boffset = value_embedded_offset (arg1) + offset; 2095 2096 if (BASETYPE_VIA_VIRTUAL (type, i)) 2097 { 2098 struct value *v2; 2099 2100 boffset = baseclass_offset (type, i, 2101 value_contents_for_printing (arg1), 2102 value_embedded_offset (arg1) + offset, 2103 value_address (arg1), 2104 arg1); 2105 2106 /* The virtual base class pointer might have been clobbered 2107 by the user program. Make sure that it still points to a 2108 valid memory location. */ 2109 2110 boffset += value_embedded_offset (arg1) + offset; 2111 if (boffset < 0 2112 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1))) 2113 { 2114 CORE_ADDR base_addr; 2115 2116 v2 = allocate_value (basetype); 2117 base_addr = value_address (arg1) + boffset; 2118 if (target_read_memory (base_addr, 2119 value_contents_raw (v2), 2120 TYPE_LENGTH (basetype)) != 0) 2121 error (_("virtual baseclass botch")); 2122 VALUE_LVAL (v2) = lval_memory; 2123 set_value_address (v2, base_addr); 2124 } 2125 else 2126 { 2127 v2 = value_copy (arg1); 2128 deprecated_set_value_type (v2, basetype); 2129 set_value_embedded_offset (v2, boffset); 2130 } 2131 2132 if (found_baseclass) 2133 v = v2; 2134 else 2135 { 2136 do_search_struct_field (name, v2, 0, 2137 TYPE_BASECLASS (type, i), 2138 looking_for_baseclass, 2139 result_ptr, last_boffset, 2140 outermost_type); 2141 } 2142 } 2143 else if (found_baseclass) 2144 v = value_primitive_field (arg1, offset, i, type); 2145 else 2146 { 2147 do_search_struct_field (name, arg1, 2148 offset + TYPE_BASECLASS_BITPOS (type, 2149 i) / 8, 2150 basetype, looking_for_baseclass, 2151 result_ptr, last_boffset, 2152 outermost_type); 2153 } 2154 2155 update_search_result (result_ptr, v, last_boffset, 2156 boffset, name, outermost_type); 2157 } 2158 } 2159 2160 /* Helper function used by value_struct_elt to recurse through 2161 baseclasses. Look for a field NAME in ARG1. Adjust the address of 2162 ARG1 by OFFSET bytes, and search in it assuming it has (class) type 2163 TYPE. If found, return value, else return NULL. 2164 2165 If LOOKING_FOR_BASECLASS, then instead of looking for struct 2166 fields, look for a baseclass named NAME. */ 2167 2168 static struct value * 2169 search_struct_field (const char *name, struct value *arg1, int offset, 2170 struct type *type, int looking_for_baseclass) 2171 { 2172 struct value *result = NULL; 2173 int boffset = 0; 2174 2175 do_search_struct_field (name, arg1, offset, type, looking_for_baseclass, 2176 &result, &boffset, type); 2177 return result; 2178 } 2179 2180 /* Helper function used by value_struct_elt to recurse through 2181 baseclasses. Look for a field NAME in ARG1. Adjust the address of 2182 ARG1 by OFFSET bytes, and search in it assuming it has (class) type 2183 TYPE. 2184 2185 If found, return value, else if name matched and args not return 2186 (value) -1, else return NULL. */ 2187 2188 static struct value * 2189 search_struct_method (const char *name, struct value **arg1p, 2190 struct value **args, int offset, 2191 int *static_memfuncp, struct type *type) 2192 { 2193 int i; 2194 struct value *v; 2195 int name_matched = 0; 2196 char dem_opname[64]; 2197 2198 CHECK_TYPEDEF (type); 2199 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--) 2200 { 2201 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i); 2202 2203 /* FIXME! May need to check for ARM demangling here. */ 2204 if (strncmp (t_field_name, "__", 2) == 0 || 2205 strncmp (t_field_name, "op", 2) == 0 || 2206 strncmp (t_field_name, "type", 4) == 0) 2207 { 2208 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI)) 2209 t_field_name = dem_opname; 2210 else if (cplus_demangle_opname (t_field_name, dem_opname, 0)) 2211 t_field_name = dem_opname; 2212 } 2213 if (t_field_name && (strcmp_iw (t_field_name, name) == 0)) 2214 { 2215 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1; 2216 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i); 2217 2218 name_matched = 1; 2219 check_stub_method_group (type, i); 2220 if (j > 0 && args == 0) 2221 error (_("cannot resolve overloaded method " 2222 "`%s': no arguments supplied"), name); 2223 else if (j == 0 && args == 0) 2224 { 2225 v = value_fn_field (arg1p, f, j, type, offset); 2226 if (v != NULL) 2227 return v; 2228 } 2229 else 2230 while (j >= 0) 2231 { 2232 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j), 2233 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)), 2234 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)), 2235 TYPE_FN_FIELD_ARGS (f, j), args)) 2236 { 2237 if (TYPE_FN_FIELD_VIRTUAL_P (f, j)) 2238 return value_virtual_fn_field (arg1p, f, j, 2239 type, offset); 2240 if (TYPE_FN_FIELD_STATIC_P (f, j) 2241 && static_memfuncp) 2242 *static_memfuncp = 1; 2243 v = value_fn_field (arg1p, f, j, type, offset); 2244 if (v != NULL) 2245 return v; 2246 } 2247 j--; 2248 } 2249 } 2250 } 2251 2252 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) 2253 { 2254 int base_offset; 2255 int this_offset; 2256 2257 if (BASETYPE_VIA_VIRTUAL (type, i)) 2258 { 2259 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i)); 2260 struct value *base_val; 2261 const gdb_byte *base_valaddr; 2262 2263 /* The virtual base class pointer might have been 2264 clobbered by the user program. Make sure that it 2265 still points to a valid memory location. */ 2266 2267 if (offset < 0 || offset >= TYPE_LENGTH (type)) 2268 { 2269 gdb_byte *tmp; 2270 struct cleanup *back_to; 2271 CORE_ADDR address; 2272 2273 tmp = xmalloc (TYPE_LENGTH (baseclass)); 2274 back_to = make_cleanup (xfree, tmp); 2275 address = value_address (*arg1p); 2276 2277 if (target_read_memory (address + offset, 2278 tmp, TYPE_LENGTH (baseclass)) != 0) 2279 error (_("virtual baseclass botch")); 2280 2281 base_val = value_from_contents_and_address (baseclass, 2282 tmp, 2283 address + offset); 2284 base_valaddr = value_contents_for_printing (base_val); 2285 this_offset = 0; 2286 do_cleanups (back_to); 2287 } 2288 else 2289 { 2290 base_val = *arg1p; 2291 base_valaddr = value_contents_for_printing (*arg1p); 2292 this_offset = offset; 2293 } 2294 2295 base_offset = baseclass_offset (type, i, base_valaddr, 2296 this_offset, value_address (base_val), 2297 base_val); 2298 } 2299 else 2300 { 2301 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8; 2302 } 2303 v = search_struct_method (name, arg1p, args, base_offset + offset, 2304 static_memfuncp, TYPE_BASECLASS (type, i)); 2305 if (v == (struct value *) - 1) 2306 { 2307 name_matched = 1; 2308 } 2309 else if (v) 2310 { 2311 /* FIXME-bothner: Why is this commented out? Why is it here? */ 2312 /* *arg1p = arg1_tmp; */ 2313 return v; 2314 } 2315 } 2316 if (name_matched) 2317 return (struct value *) - 1; 2318 else 2319 return NULL; 2320 } 2321 2322 /* Given *ARGP, a value of type (pointer to a)* structure/union, 2323 extract the component named NAME from the ultimate target 2324 structure/union and return it as a value with its appropriate type. 2325 ERR is used in the error message if *ARGP's type is wrong. 2326 2327 C++: ARGS is a list of argument types to aid in the selection of 2328 an appropriate method. Also, handle derived types. 2329 2330 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location 2331 where the truthvalue of whether the function that was resolved was 2332 a static member function or not is stored. 2333 2334 ERR is an error message to be printed in case the field is not 2335 found. */ 2336 2337 struct value * 2338 value_struct_elt (struct value **argp, struct value **args, 2339 const char *name, int *static_memfuncp, const char *err) 2340 { 2341 struct type *t; 2342 struct value *v; 2343 2344 *argp = coerce_array (*argp); 2345 2346 t = check_typedef (value_type (*argp)); 2347 2348 /* Follow pointers until we get to a non-pointer. */ 2349 2350 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF) 2351 { 2352 *argp = value_ind (*argp); 2353 /* Don't coerce fn pointer to fn and then back again! */ 2354 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC) 2355 *argp = coerce_array (*argp); 2356 t = check_typedef (value_type (*argp)); 2357 } 2358 2359 if (TYPE_CODE (t) != TYPE_CODE_STRUCT 2360 && TYPE_CODE (t) != TYPE_CODE_UNION) 2361 error (_("Attempt to extract a component of a value that is not a %s."), 2362 err); 2363 2364 /* Assume it's not, unless we see that it is. */ 2365 if (static_memfuncp) 2366 *static_memfuncp = 0; 2367 2368 if (!args) 2369 { 2370 /* if there are no arguments ...do this... */ 2371 2372 /* Try as a field first, because if we succeed, there is less 2373 work to be done. */ 2374 v = search_struct_field (name, *argp, 0, t, 0); 2375 if (v) 2376 return v; 2377 2378 /* C++: If it was not found as a data field, then try to 2379 return it as a pointer to a method. */ 2380 v = search_struct_method (name, argp, args, 0, 2381 static_memfuncp, t); 2382 2383 if (v == (struct value *) - 1) 2384 error (_("Cannot take address of method %s."), name); 2385 else if (v == 0) 2386 { 2387 if (TYPE_NFN_FIELDS (t)) 2388 error (_("There is no member or method named %s."), name); 2389 else 2390 error (_("There is no member named %s."), name); 2391 } 2392 return v; 2393 } 2394 2395 v = search_struct_method (name, argp, args, 0, 2396 static_memfuncp, t); 2397 2398 if (v == (struct value *) - 1) 2399 { 2400 error (_("One of the arguments you tried to pass to %s could not " 2401 "be converted to what the function wants."), name); 2402 } 2403 else if (v == 0) 2404 { 2405 /* See if user tried to invoke data as function. If so, hand it 2406 back. If it's not callable (i.e., a pointer to function), 2407 gdb should give an error. */ 2408 v = search_struct_field (name, *argp, 0, t, 0); 2409 /* If we found an ordinary field, then it is not a method call. 2410 So, treat it as if it were a static member function. */ 2411 if (v && static_memfuncp) 2412 *static_memfuncp = 1; 2413 } 2414 2415 if (!v) 2416 throw_error (NOT_FOUND_ERROR, 2417 _("Structure has no component named %s."), name); 2418 return v; 2419 } 2420 2421 /* Search through the methods of an object (and its bases) to find a 2422 specified method. Return the pointer to the fn_field list of 2423 overloaded instances. 2424 2425 Helper function for value_find_oload_list. 2426 ARGP is a pointer to a pointer to a value (the object). 2427 METHOD is a string containing the method name. 2428 OFFSET is the offset within the value. 2429 TYPE is the assumed type of the object. 2430 NUM_FNS is the number of overloaded instances. 2431 BASETYPE is set to the actual type of the subobject where the 2432 method is found. 2433 BOFFSET is the offset of the base subobject where the method is found. */ 2434 2435 static struct fn_field * 2436 find_method_list (struct value **argp, const char *method, 2437 int offset, struct type *type, int *num_fns, 2438 struct type **basetype, int *boffset) 2439 { 2440 int i; 2441 struct fn_field *f; 2442 CHECK_TYPEDEF (type); 2443 2444 *num_fns = 0; 2445 2446 /* First check in object itself. */ 2447 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--) 2448 { 2449 /* pai: FIXME What about operators and type conversions? */ 2450 const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i); 2451 2452 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0)) 2453 { 2454 int len = TYPE_FN_FIELDLIST_LENGTH (type, i); 2455 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i); 2456 2457 *num_fns = len; 2458 *basetype = type; 2459 *boffset = offset; 2460 2461 /* Resolve any stub methods. */ 2462 check_stub_method_group (type, i); 2463 2464 return f; 2465 } 2466 } 2467 2468 /* Not found in object, check in base subobjects. */ 2469 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) 2470 { 2471 int base_offset; 2472 2473 if (BASETYPE_VIA_VIRTUAL (type, i)) 2474 { 2475 base_offset = baseclass_offset (type, i, 2476 value_contents_for_printing (*argp), 2477 value_offset (*argp) + offset, 2478 value_address (*argp), *argp); 2479 } 2480 else /* Non-virtual base, simply use bit position from debug 2481 info. */ 2482 { 2483 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8; 2484 } 2485 f = find_method_list (argp, method, base_offset + offset, 2486 TYPE_BASECLASS (type, i), num_fns, 2487 basetype, boffset); 2488 if (f) 2489 return f; 2490 } 2491 return NULL; 2492 } 2493 2494 /* Return the list of overloaded methods of a specified name. 2495 2496 ARGP is a pointer to a pointer to a value (the object). 2497 METHOD is the method name. 2498 OFFSET is the offset within the value contents. 2499 NUM_FNS is the number of overloaded instances. 2500 BASETYPE is set to the type of the base subobject that defines the 2501 method. 2502 BOFFSET is the offset of the base subobject which defines the method. */ 2503 2504 static struct fn_field * 2505 value_find_oload_method_list (struct value **argp, const char *method, 2506 int offset, int *num_fns, 2507 struct type **basetype, int *boffset) 2508 { 2509 struct type *t; 2510 2511 t = check_typedef (value_type (*argp)); 2512 2513 /* Code snarfed from value_struct_elt. */ 2514 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF) 2515 { 2516 *argp = value_ind (*argp); 2517 /* Don't coerce fn pointer to fn and then back again! */ 2518 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC) 2519 *argp = coerce_array (*argp); 2520 t = check_typedef (value_type (*argp)); 2521 } 2522 2523 if (TYPE_CODE (t) != TYPE_CODE_STRUCT 2524 && TYPE_CODE (t) != TYPE_CODE_UNION) 2525 error (_("Attempt to extract a component of a " 2526 "value that is not a struct or union")); 2527 2528 return find_method_list (argp, method, 0, t, num_fns, 2529 basetype, boffset); 2530 } 2531 2532 /* Given an array of arguments (ARGS) (which includes an 2533 entry for "this" in the case of C++ methods), the number of 2534 arguments NARGS, the NAME of a function, and whether it's a method or 2535 not (METHOD), find the best function that matches on the argument types 2536 according to the overload resolution rules. 2537 2538 METHOD can be one of three values: 2539 NON_METHOD for non-member functions. 2540 METHOD: for member functions. 2541 BOTH: used for overload resolution of operators where the 2542 candidates are expected to be either member or non member 2543 functions. In this case the first argument ARGTYPES 2544 (representing 'this') is expected to be a reference to the 2545 target object, and will be dereferenced when attempting the 2546 non-member search. 2547 2548 In the case of class methods, the parameter OBJ is an object value 2549 in which to search for overloaded methods. 2550 2551 In the case of non-method functions, the parameter FSYM is a symbol 2552 corresponding to one of the overloaded functions. 2553 2554 Return value is an integer: 0 -> good match, 10 -> debugger applied 2555 non-standard coercions, 100 -> incompatible. 2556 2557 If a method is being searched for, VALP will hold the value. 2558 If a non-method is being searched for, SYMP will hold the symbol 2559 for it. 2560 2561 If a method is being searched for, and it is a static method, 2562 then STATICP will point to a non-zero value. 2563 2564 If NO_ADL argument dependent lookup is disabled. This is used to prevent 2565 ADL overload candidates when performing overload resolution for a fully 2566 qualified name. 2567 2568 Note: This function does *not* check the value of 2569 overload_resolution. Caller must check it to see whether overload 2570 resolution is permitted. */ 2571 2572 int 2573 find_overload_match (struct value **args, int nargs, 2574 const char *name, enum oload_search_type method, 2575 struct value **objp, struct symbol *fsym, 2576 struct value **valp, struct symbol **symp, 2577 int *staticp, const int no_adl) 2578 { 2579 struct value *obj = (objp ? *objp : NULL); 2580 struct type *obj_type = obj ? value_type (obj) : NULL; 2581 /* Index of best overloaded function. */ 2582 int func_oload_champ = -1; 2583 int method_oload_champ = -1; 2584 2585 /* The measure for the current best match. */ 2586 struct badness_vector *method_badness = NULL; 2587 struct badness_vector *func_badness = NULL; 2588 2589 struct value *temp = obj; 2590 /* For methods, the list of overloaded methods. */ 2591 struct fn_field *fns_ptr = NULL; 2592 /* For non-methods, the list of overloaded function symbols. */ 2593 struct symbol **oload_syms = NULL; 2594 /* Number of overloaded instances being considered. */ 2595 int num_fns = 0; 2596 struct type *basetype = NULL; 2597 int boffset; 2598 2599 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL); 2600 2601 const char *obj_type_name = NULL; 2602 const char *func_name = NULL; 2603 enum oload_classification match_quality; 2604 enum oload_classification method_match_quality = INCOMPATIBLE; 2605 enum oload_classification func_match_quality = INCOMPATIBLE; 2606 2607 /* Get the list of overloaded methods or functions. */ 2608 if (method == METHOD || method == BOTH) 2609 { 2610 gdb_assert (obj); 2611 2612 /* OBJ may be a pointer value rather than the object itself. */ 2613 obj = coerce_ref (obj); 2614 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR) 2615 obj = coerce_ref (value_ind (obj)); 2616 obj_type_name = TYPE_NAME (value_type (obj)); 2617 2618 /* First check whether this is a data member, e.g. a pointer to 2619 a function. */ 2620 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT) 2621 { 2622 *valp = search_struct_field (name, obj, 0, 2623 check_typedef (value_type (obj)), 0); 2624 if (*valp) 2625 { 2626 *staticp = 1; 2627 do_cleanups (all_cleanups); 2628 return 0; 2629 } 2630 } 2631 2632 /* Retrieve the list of methods with the name NAME. */ 2633 fns_ptr = value_find_oload_method_list (&temp, name, 2634 0, &num_fns, 2635 &basetype, &boffset); 2636 /* If this is a method only search, and no methods were found 2637 the search has faild. */ 2638 if (method == METHOD && (!fns_ptr || !num_fns)) 2639 error (_("Couldn't find method %s%s%s"), 2640 obj_type_name, 2641 (obj_type_name && *obj_type_name) ? "::" : "", 2642 name); 2643 /* If we are dealing with stub method types, they should have 2644 been resolved by find_method_list via 2645 value_find_oload_method_list above. */ 2646 if (fns_ptr) 2647 { 2648 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL); 2649 method_oload_champ = find_oload_champ (args, nargs, method, 2650 num_fns, fns_ptr, 2651 oload_syms, &method_badness); 2652 2653 method_match_quality = 2654 classify_oload_match (method_badness, nargs, 2655 oload_method_static (method, fns_ptr, 2656 method_oload_champ)); 2657 2658 make_cleanup (xfree, method_badness); 2659 } 2660 2661 } 2662 2663 if (method == NON_METHOD || method == BOTH) 2664 { 2665 const char *qualified_name = NULL; 2666 2667 /* If the overload match is being search for both as a method 2668 and non member function, the first argument must now be 2669 dereferenced. */ 2670 if (method == BOTH) 2671 args[0] = value_ind (args[0]); 2672 2673 if (fsym) 2674 { 2675 qualified_name = SYMBOL_NATURAL_NAME (fsym); 2676 2677 /* If we have a function with a C++ name, try to extract just 2678 the function part. Do not try this for non-functions (e.g. 2679 function pointers). */ 2680 if (qualified_name 2681 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym))) 2682 == TYPE_CODE_FUNC) 2683 { 2684 char *temp; 2685 2686 temp = cp_func_name (qualified_name); 2687 2688 /* If cp_func_name did not remove anything, the name of the 2689 symbol did not include scope or argument types - it was 2690 probably a C-style function. */ 2691 if (temp) 2692 { 2693 make_cleanup (xfree, temp); 2694 if (strcmp (temp, qualified_name) == 0) 2695 func_name = NULL; 2696 else 2697 func_name = temp; 2698 } 2699 } 2700 } 2701 else 2702 { 2703 func_name = name; 2704 qualified_name = name; 2705 } 2706 2707 /* If there was no C++ name, this must be a C-style function or 2708 not a function at all. Just return the same symbol. Do the 2709 same if cp_func_name fails for some reason. */ 2710 if (func_name == NULL) 2711 { 2712 *symp = fsym; 2713 do_cleanups (all_cleanups); 2714 return 0; 2715 } 2716 2717 func_oload_champ = find_oload_champ_namespace (args, nargs, 2718 func_name, 2719 qualified_name, 2720 &oload_syms, 2721 &func_badness, 2722 no_adl); 2723 2724 if (func_oload_champ >= 0) 2725 func_match_quality = classify_oload_match (func_badness, nargs, 0); 2726 2727 make_cleanup (xfree, oload_syms); 2728 make_cleanup (xfree, func_badness); 2729 } 2730 2731 /* Did we find a match ? */ 2732 if (method_oload_champ == -1 && func_oload_champ == -1) 2733 throw_error (NOT_FOUND_ERROR, 2734 _("No symbol \"%s\" in current context."), 2735 name); 2736 2737 /* If we have found both a method match and a function 2738 match, find out which one is better, and calculate match 2739 quality. */ 2740 if (method_oload_champ >= 0 && func_oload_champ >= 0) 2741 { 2742 switch (compare_badness (func_badness, method_badness)) 2743 { 2744 case 0: /* Top two contenders are equally good. */ 2745 /* FIXME: GDB does not support the general ambiguous case. 2746 All candidates should be collected and presented the 2747 user. */ 2748 error (_("Ambiguous overload resolution")); 2749 break; 2750 case 1: /* Incomparable top contenders. */ 2751 /* This is an error incompatible candidates 2752 should not have been proposed. */ 2753 error (_("Internal error: incompatible " 2754 "overload candidates proposed")); 2755 break; 2756 case 2: /* Function champion. */ 2757 method_oload_champ = -1; 2758 match_quality = func_match_quality; 2759 break; 2760 case 3: /* Method champion. */ 2761 func_oload_champ = -1; 2762 match_quality = method_match_quality; 2763 break; 2764 default: 2765 error (_("Internal error: unexpected overload comparison result")); 2766 break; 2767 } 2768 } 2769 else 2770 { 2771 /* We have either a method match or a function match. */ 2772 if (method_oload_champ >= 0) 2773 match_quality = method_match_quality; 2774 else 2775 match_quality = func_match_quality; 2776 } 2777 2778 if (match_quality == INCOMPATIBLE) 2779 { 2780 if (method == METHOD) 2781 error (_("Cannot resolve method %s%s%s to any overloaded instance"), 2782 obj_type_name, 2783 (obj_type_name && *obj_type_name) ? "::" : "", 2784 name); 2785 else 2786 error (_("Cannot resolve function %s to any overloaded instance"), 2787 func_name); 2788 } 2789 else if (match_quality == NON_STANDARD) 2790 { 2791 if (method == METHOD) 2792 warning (_("Using non-standard conversion to match " 2793 "method %s%s%s to supplied arguments"), 2794 obj_type_name, 2795 (obj_type_name && *obj_type_name) ? "::" : "", 2796 name); 2797 else 2798 warning (_("Using non-standard conversion to match " 2799 "function %s to supplied arguments"), 2800 func_name); 2801 } 2802 2803 if (staticp != NULL) 2804 *staticp = oload_method_static (method, fns_ptr, method_oload_champ); 2805 2806 if (method_oload_champ >= 0) 2807 { 2808 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ)) 2809 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ, 2810 basetype, boffset); 2811 else 2812 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ, 2813 basetype, boffset); 2814 } 2815 else 2816 *symp = oload_syms[func_oload_champ]; 2817 2818 if (objp) 2819 { 2820 struct type *temp_type = check_typedef (value_type (temp)); 2821 struct type *objtype = check_typedef (obj_type); 2822 2823 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR 2824 && (TYPE_CODE (objtype) == TYPE_CODE_PTR 2825 || TYPE_CODE (objtype) == TYPE_CODE_REF)) 2826 { 2827 temp = value_addr (temp); 2828 } 2829 *objp = temp; 2830 } 2831 2832 do_cleanups (all_cleanups); 2833 2834 switch (match_quality) 2835 { 2836 case INCOMPATIBLE: 2837 return 100; 2838 case NON_STANDARD: 2839 return 10; 2840 default: /* STANDARD */ 2841 return 0; 2842 } 2843 } 2844 2845 /* Find the best overload match, searching for FUNC_NAME in namespaces 2846 contained in QUALIFIED_NAME until it either finds a good match or 2847 runs out of namespaces. It stores the overloaded functions in 2848 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The 2849 calling function is responsible for freeing *OLOAD_SYMS and 2850 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not 2851 performned. */ 2852 2853 static int 2854 find_oload_champ_namespace (struct value **args, int nargs, 2855 const char *func_name, 2856 const char *qualified_name, 2857 struct symbol ***oload_syms, 2858 struct badness_vector **oload_champ_bv, 2859 const int no_adl) 2860 { 2861 int oload_champ; 2862 2863 find_oload_champ_namespace_loop (args, nargs, 2864 func_name, 2865 qualified_name, 0, 2866 oload_syms, oload_champ_bv, 2867 &oload_champ, 2868 no_adl); 2869 2870 return oload_champ; 2871 } 2872 2873 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is 2874 how deep we've looked for namespaces, and the champ is stored in 2875 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0 2876 if it isn't. Other arguments are the same as in 2877 find_oload_champ_namespace 2878 2879 It is the caller's responsibility to free *OLOAD_SYMS and 2880 *OLOAD_CHAMP_BV. */ 2881 2882 static int 2883 find_oload_champ_namespace_loop (struct value **args, int nargs, 2884 const char *func_name, 2885 const char *qualified_name, 2886 int namespace_len, 2887 struct symbol ***oload_syms, 2888 struct badness_vector **oload_champ_bv, 2889 int *oload_champ, 2890 const int no_adl) 2891 { 2892 int next_namespace_len = namespace_len; 2893 int searched_deeper = 0; 2894 int num_fns = 0; 2895 struct cleanup *old_cleanups; 2896 int new_oload_champ; 2897 struct symbol **new_oload_syms; 2898 struct badness_vector *new_oload_champ_bv; 2899 char *new_namespace; 2900 2901 if (next_namespace_len != 0) 2902 { 2903 gdb_assert (qualified_name[next_namespace_len] == ':'); 2904 next_namespace_len += 2; 2905 } 2906 next_namespace_len += 2907 cp_find_first_component (qualified_name + next_namespace_len); 2908 2909 /* Initialize these to values that can safely be xfree'd. */ 2910 *oload_syms = NULL; 2911 *oload_champ_bv = NULL; 2912 2913 /* First, see if we have a deeper namespace we can search in. 2914 If we get a good match there, use it. */ 2915 2916 if (qualified_name[next_namespace_len] == ':') 2917 { 2918 searched_deeper = 1; 2919 2920 if (find_oload_champ_namespace_loop (args, nargs, 2921 func_name, qualified_name, 2922 next_namespace_len, 2923 oload_syms, oload_champ_bv, 2924 oload_champ, no_adl)) 2925 { 2926 return 1; 2927 } 2928 }; 2929 2930 /* If we reach here, either we're in the deepest namespace or we 2931 didn't find a good match in a deeper namespace. But, in the 2932 latter case, we still have a bad match in a deeper namespace; 2933 note that we might not find any match at all in the current 2934 namespace. (There's always a match in the deepest namespace, 2935 because this overload mechanism only gets called if there's a 2936 function symbol to start off with.) */ 2937 2938 old_cleanups = make_cleanup (xfree, *oload_syms); 2939 make_cleanup (xfree, *oload_champ_bv); 2940 new_namespace = alloca (namespace_len + 1); 2941 strncpy (new_namespace, qualified_name, namespace_len); 2942 new_namespace[namespace_len] = '\0'; 2943 new_oload_syms = make_symbol_overload_list (func_name, 2944 new_namespace); 2945 2946 /* If we have reached the deepest level perform argument 2947 determined lookup. */ 2948 if (!searched_deeper && !no_adl) 2949 { 2950 int ix; 2951 struct type **arg_types; 2952 2953 /* Prepare list of argument types for overload resolution. */ 2954 arg_types = (struct type **) 2955 alloca (nargs * (sizeof (struct type *))); 2956 for (ix = 0; ix < nargs; ix++) 2957 arg_types[ix] = value_type (args[ix]); 2958 make_symbol_overload_list_adl (arg_types, nargs, func_name); 2959 } 2960 2961 while (new_oload_syms[num_fns]) 2962 ++num_fns; 2963 2964 new_oload_champ = find_oload_champ (args, nargs, 0, num_fns, 2965 NULL, new_oload_syms, 2966 &new_oload_champ_bv); 2967 2968 /* Case 1: We found a good match. Free earlier matches (if any), 2969 and return it. Case 2: We didn't find a good match, but we're 2970 not the deepest function. Then go with the bad match that the 2971 deeper function found. Case 3: We found a bad match, and we're 2972 the deepest function. Then return what we found, even though 2973 it's a bad match. */ 2974 2975 if (new_oload_champ != -1 2976 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD) 2977 { 2978 *oload_syms = new_oload_syms; 2979 *oload_champ = new_oload_champ; 2980 *oload_champ_bv = new_oload_champ_bv; 2981 do_cleanups (old_cleanups); 2982 return 1; 2983 } 2984 else if (searched_deeper) 2985 { 2986 xfree (new_oload_syms); 2987 xfree (new_oload_champ_bv); 2988 discard_cleanups (old_cleanups); 2989 return 0; 2990 } 2991 else 2992 { 2993 *oload_syms = new_oload_syms; 2994 *oload_champ = new_oload_champ; 2995 *oload_champ_bv = new_oload_champ_bv; 2996 do_cleanups (old_cleanups); 2997 return 0; 2998 } 2999 } 3000 3001 /* Look for a function to take NARGS args of ARGS. Find 3002 the best match from among the overloaded methods or functions 3003 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively. 3004 The number of methods/functions in the list is given by NUM_FNS. 3005 Return the index of the best match; store an indication of the 3006 quality of the match in OLOAD_CHAMP_BV. 3007 3008 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */ 3009 3010 static int 3011 find_oload_champ (struct value **args, int nargs, int method, 3012 int num_fns, struct fn_field *fns_ptr, 3013 struct symbol **oload_syms, 3014 struct badness_vector **oload_champ_bv) 3015 { 3016 int ix; 3017 /* A measure of how good an overloaded instance is. */ 3018 struct badness_vector *bv; 3019 /* Index of best overloaded function. */ 3020 int oload_champ = -1; 3021 /* Current ambiguity state for overload resolution. */ 3022 int oload_ambiguous = 0; 3023 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */ 3024 3025 *oload_champ_bv = NULL; 3026 3027 /* Consider each candidate in turn. */ 3028 for (ix = 0; ix < num_fns; ix++) 3029 { 3030 int jj; 3031 int static_offset = oload_method_static (method, fns_ptr, ix); 3032 int nparms; 3033 struct type **parm_types; 3034 3035 if (method) 3036 { 3037 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix)); 3038 } 3039 else 3040 { 3041 /* If it's not a method, this is the proper place. */ 3042 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix])); 3043 } 3044 3045 /* Prepare array of parameter types. */ 3046 parm_types = (struct type **) 3047 xmalloc (nparms * (sizeof (struct type *))); 3048 for (jj = 0; jj < nparms; jj++) 3049 parm_types[jj] = (method 3050 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type) 3051 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), 3052 jj)); 3053 3054 /* Compare parameter types to supplied argument types. Skip 3055 THIS for static methods. */ 3056 bv = rank_function (parm_types, nparms, 3057 args + static_offset, 3058 nargs - static_offset); 3059 3060 if (!*oload_champ_bv) 3061 { 3062 *oload_champ_bv = bv; 3063 oload_champ = 0; 3064 } 3065 else /* See whether current candidate is better or worse than 3066 previous best. */ 3067 switch (compare_badness (bv, *oload_champ_bv)) 3068 { 3069 case 0: /* Top two contenders are equally good. */ 3070 oload_ambiguous = 1; 3071 break; 3072 case 1: /* Incomparable top contenders. */ 3073 oload_ambiguous = 2; 3074 break; 3075 case 2: /* New champion, record details. */ 3076 *oload_champ_bv = bv; 3077 oload_ambiguous = 0; 3078 oload_champ = ix; 3079 break; 3080 case 3: 3081 default: 3082 break; 3083 } 3084 xfree (parm_types); 3085 if (overload_debug) 3086 { 3087 if (method) 3088 fprintf_filtered (gdb_stderr, 3089 "Overloaded method instance %s, # of parms %d\n", 3090 fns_ptr[ix].physname, nparms); 3091 else 3092 fprintf_filtered (gdb_stderr, 3093 "Overloaded function instance " 3094 "%s # of parms %d\n", 3095 SYMBOL_DEMANGLED_NAME (oload_syms[ix]), 3096 nparms); 3097 for (jj = 0; jj < nargs - static_offset; jj++) 3098 fprintf_filtered (gdb_stderr, 3099 "...Badness @ %d : %d\n", 3100 jj, bv->rank[jj].rank); 3101 fprintf_filtered (gdb_stderr, "Overload resolution " 3102 "champion is %d, ambiguous? %d\n", 3103 oload_champ, oload_ambiguous); 3104 } 3105 } 3106 3107 return oload_champ; 3108 } 3109 3110 /* Return 1 if we're looking at a static method, 0 if we're looking at 3111 a non-static method or a function that isn't a method. */ 3112 3113 static int 3114 oload_method_static (int method, struct fn_field *fns_ptr, int index) 3115 { 3116 if (method && fns_ptr && index >= 0 3117 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index)) 3118 return 1; 3119 else 3120 return 0; 3121 } 3122 3123 /* Check how good an overload match OLOAD_CHAMP_BV represents. */ 3124 3125 static enum oload_classification 3126 classify_oload_match (struct badness_vector *oload_champ_bv, 3127 int nargs, 3128 int static_offset) 3129 { 3130 int ix; 3131 enum oload_classification worst = STANDARD; 3132 3133 for (ix = 1; ix <= nargs - static_offset; ix++) 3134 { 3135 /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS 3136 or worse return INCOMPATIBLE. */ 3137 if (compare_ranks (oload_champ_bv->rank[ix], 3138 INCOMPATIBLE_TYPE_BADNESS) <= 0) 3139 return INCOMPATIBLE; /* Truly mismatched types. */ 3140 /* Otherwise If this conversion is as bad as 3141 NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */ 3142 else if (compare_ranks (oload_champ_bv->rank[ix], 3143 NS_POINTER_CONVERSION_BADNESS) <= 0) 3144 worst = NON_STANDARD; /* Non-standard type conversions 3145 needed. */ 3146 } 3147 3148 /* If no INCOMPATIBLE classification was found, return the worst one 3149 that was found (if any). */ 3150 return worst; 3151 } 3152 3153 /* C++: return 1 is NAME is a legitimate name for the destructor of 3154 type TYPE. If TYPE does not have a destructor, or if NAME is 3155 inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet 3156 have CHECK_TYPEDEF applied, this function will apply it itself. */ 3157 3158 int 3159 destructor_name_p (const char *name, struct type *type) 3160 { 3161 if (name[0] == '~') 3162 { 3163 const char *dname = type_name_no_tag_or_error (type); 3164 const char *cp = strchr (dname, '<'); 3165 unsigned int len; 3166 3167 /* Do not compare the template part for template classes. */ 3168 if (cp == NULL) 3169 len = strlen (dname); 3170 else 3171 len = cp - dname; 3172 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0) 3173 error (_("name of destructor must equal name of class")); 3174 else 3175 return 1; 3176 } 3177 return 0; 3178 } 3179 3180 /* C++: Given an aggregate type CURTYPE, and a member name NAME, 3181 return the appropriate member (or the address of the member, if 3182 WANT_ADDRESS). This function is used to resolve user expressions 3183 of the form "DOMAIN::NAME". For more details on what happens, see 3184 the comment before value_struct_elt_for_reference. */ 3185 3186 struct value * 3187 value_aggregate_elt (struct type *curtype, char *name, 3188 struct type *expect_type, int want_address, 3189 enum noside noside) 3190 { 3191 switch (TYPE_CODE (curtype)) 3192 { 3193 case TYPE_CODE_STRUCT: 3194 case TYPE_CODE_UNION: 3195 return value_struct_elt_for_reference (curtype, 0, curtype, 3196 name, expect_type, 3197 want_address, noside); 3198 case TYPE_CODE_NAMESPACE: 3199 return value_namespace_elt (curtype, name, 3200 want_address, noside); 3201 default: 3202 internal_error (__FILE__, __LINE__, 3203 _("non-aggregate type in value_aggregate_elt")); 3204 } 3205 } 3206 3207 /* Compares the two method/function types T1 and T2 for "equality" 3208 with respect to the methods' parameters. If the types of the 3209 two parameter lists are the same, returns 1; 0 otherwise. This 3210 comparison may ignore any artificial parameters in T1 if 3211 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip 3212 the first artificial parameter in T1, assumed to be a 'this' pointer. 3213 3214 The type T2 is expected to have come from make_params (in eval.c). */ 3215 3216 static int 3217 compare_parameters (struct type *t1, struct type *t2, int skip_artificial) 3218 { 3219 int start = 0; 3220 3221 if (TYPE_NFIELDS (t1) > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0)) 3222 ++start; 3223 3224 /* If skipping artificial fields, find the first real field 3225 in T1. */ 3226 if (skip_artificial) 3227 { 3228 while (start < TYPE_NFIELDS (t1) 3229 && TYPE_FIELD_ARTIFICIAL (t1, start)) 3230 ++start; 3231 } 3232 3233 /* Now compare parameters. */ 3234 3235 /* Special case: a method taking void. T1 will contain no 3236 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */ 3237 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1 3238 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID) 3239 return 1; 3240 3241 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2)) 3242 { 3243 int i; 3244 3245 for (i = 0; i < TYPE_NFIELDS (t2); ++i) 3246 { 3247 if (compare_ranks (rank_one_type (TYPE_FIELD_TYPE (t1, start + i), 3248 TYPE_FIELD_TYPE (t2, i), NULL), 3249 EXACT_MATCH_BADNESS) != 0) 3250 return 0; 3251 } 3252 3253 return 1; 3254 } 3255 3256 return 0; 3257 } 3258 3259 /* C++: Given an aggregate type CURTYPE, and a member name NAME, 3260 return the address of this member as a "pointer to member" type. 3261 If INTYPE is non-null, then it will be the type of the member we 3262 are looking for. This will help us resolve "pointers to member 3263 functions". This function is used to resolve user expressions of 3264 the form "DOMAIN::NAME". */ 3265 3266 static struct value * 3267 value_struct_elt_for_reference (struct type *domain, int offset, 3268 struct type *curtype, char *name, 3269 struct type *intype, 3270 int want_address, 3271 enum noside noside) 3272 { 3273 struct type *t = curtype; 3274 int i; 3275 struct value *v, *result; 3276 3277 if (TYPE_CODE (t) != TYPE_CODE_STRUCT 3278 && TYPE_CODE (t) != TYPE_CODE_UNION) 3279 error (_("Internal error: non-aggregate type " 3280 "to value_struct_elt_for_reference")); 3281 3282 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--) 3283 { 3284 const char *t_field_name = TYPE_FIELD_NAME (t, i); 3285 3286 if (t_field_name && strcmp (t_field_name, name) == 0) 3287 { 3288 if (field_is_static (&TYPE_FIELD (t, i))) 3289 { 3290 v = value_static_field (t, i); 3291 if (v == NULL) 3292 error (_("static field %s has been optimized out"), 3293 name); 3294 if (want_address) 3295 v = value_addr (v); 3296 return v; 3297 } 3298 if (TYPE_FIELD_PACKED (t, i)) 3299 error (_("pointers to bitfield members not allowed")); 3300 3301 if (want_address) 3302 return value_from_longest 3303 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain), 3304 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3)); 3305 else if (noside == EVAL_AVOID_SIDE_EFFECTS) 3306 return allocate_value (TYPE_FIELD_TYPE (t, i)); 3307 else 3308 error (_("Cannot reference non-static field \"%s\""), name); 3309 } 3310 } 3311 3312 /* C++: If it was not found as a data field, then try to return it 3313 as a pointer to a method. */ 3314 3315 /* Perform all necessary dereferencing. */ 3316 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR) 3317 intype = TYPE_TARGET_TYPE (intype); 3318 3319 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i) 3320 { 3321 const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i); 3322 char dem_opname[64]; 3323 3324 if (strncmp (t_field_name, "__", 2) == 0 3325 || strncmp (t_field_name, "op", 2) == 0 3326 || strncmp (t_field_name, "type", 4) == 0) 3327 { 3328 if (cplus_demangle_opname (t_field_name, 3329 dem_opname, DMGL_ANSI)) 3330 t_field_name = dem_opname; 3331 else if (cplus_demangle_opname (t_field_name, 3332 dem_opname, 0)) 3333 t_field_name = dem_opname; 3334 } 3335 if (t_field_name && strcmp (t_field_name, name) == 0) 3336 { 3337 int j; 3338 int len = TYPE_FN_FIELDLIST_LENGTH (t, i); 3339 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i); 3340 3341 check_stub_method_group (t, i); 3342 3343 if (intype) 3344 { 3345 for (j = 0; j < len; ++j) 3346 { 3347 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0) 3348 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j), 3349 intype, 1)) 3350 break; 3351 } 3352 3353 if (j == len) 3354 error (_("no member function matches " 3355 "that type instantiation")); 3356 } 3357 else 3358 { 3359 int ii; 3360 3361 j = -1; 3362 for (ii = 0; ii < len; ++ii) 3363 { 3364 /* Skip artificial methods. This is necessary if, 3365 for example, the user wants to "print 3366 subclass::subclass" with only one user-defined 3367 constructor. There is no ambiguity in this case. 3368 We are careful here to allow artificial methods 3369 if they are the unique result. */ 3370 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii)) 3371 { 3372 if (j == -1) 3373 j = ii; 3374 continue; 3375 } 3376 3377 /* Desired method is ambiguous if more than one 3378 method is defined. */ 3379 if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j)) 3380 error (_("non-unique member `%s' requires " 3381 "type instantiation"), name); 3382 3383 j = ii; 3384 } 3385 3386 if (j == -1) 3387 error (_("no matching member function")); 3388 } 3389 3390 if (TYPE_FN_FIELD_STATIC_P (f, j)) 3391 { 3392 struct symbol *s = 3393 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j), 3394 0, VAR_DOMAIN, 0); 3395 3396 if (s == NULL) 3397 return NULL; 3398 3399 if (want_address) 3400 return value_addr (read_var_value (s, 0)); 3401 else 3402 return read_var_value (s, 0); 3403 } 3404 3405 if (TYPE_FN_FIELD_VIRTUAL_P (f, j)) 3406 { 3407 if (want_address) 3408 { 3409 result = allocate_value 3410 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j))); 3411 cplus_make_method_ptr (value_type (result), 3412 value_contents_writeable (result), 3413 TYPE_FN_FIELD_VOFFSET (f, j), 1); 3414 } 3415 else if (noside == EVAL_AVOID_SIDE_EFFECTS) 3416 return allocate_value (TYPE_FN_FIELD_TYPE (f, j)); 3417 else 3418 error (_("Cannot reference virtual member function \"%s\""), 3419 name); 3420 } 3421 else 3422 { 3423 struct symbol *s = 3424 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j), 3425 0, VAR_DOMAIN, 0); 3426 3427 if (s == NULL) 3428 return NULL; 3429 3430 v = read_var_value (s, 0); 3431 if (!want_address) 3432 result = v; 3433 else 3434 { 3435 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j))); 3436 cplus_make_method_ptr (value_type (result), 3437 value_contents_writeable (result), 3438 value_address (v), 0); 3439 } 3440 } 3441 return result; 3442 } 3443 } 3444 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--) 3445 { 3446 struct value *v; 3447 int base_offset; 3448 3449 if (BASETYPE_VIA_VIRTUAL (t, i)) 3450 base_offset = 0; 3451 else 3452 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8; 3453 v = value_struct_elt_for_reference (domain, 3454 offset + base_offset, 3455 TYPE_BASECLASS (t, i), 3456 name, intype, 3457 want_address, noside); 3458 if (v) 3459 return v; 3460 } 3461 3462 /* As a last chance, pretend that CURTYPE is a namespace, and look 3463 it up that way; this (frequently) works for types nested inside 3464 classes. */ 3465 3466 return value_maybe_namespace_elt (curtype, name, 3467 want_address, noside); 3468 } 3469 3470 /* C++: Return the member NAME of the namespace given by the type 3471 CURTYPE. */ 3472 3473 static struct value * 3474 value_namespace_elt (const struct type *curtype, 3475 char *name, int want_address, 3476 enum noside noside) 3477 { 3478 struct value *retval = value_maybe_namespace_elt (curtype, name, 3479 want_address, 3480 noside); 3481 3482 if (retval == NULL) 3483 error (_("No symbol \"%s\" in namespace \"%s\"."), 3484 name, TYPE_TAG_NAME (curtype)); 3485 3486 return retval; 3487 } 3488 3489 /* A helper function used by value_namespace_elt and 3490 value_struct_elt_for_reference. It looks up NAME inside the 3491 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE 3492 is a class and NAME refers to a type in CURTYPE itself (as opposed 3493 to, say, some base class of CURTYPE). */ 3494 3495 static struct value * 3496 value_maybe_namespace_elt (const struct type *curtype, 3497 char *name, int want_address, 3498 enum noside noside) 3499 { 3500 const char *namespace_name = TYPE_TAG_NAME (curtype); 3501 struct symbol *sym; 3502 struct value *result; 3503 3504 sym = cp_lookup_symbol_namespace (namespace_name, name, 3505 get_selected_block (0), VAR_DOMAIN); 3506 3507 if (sym == NULL) 3508 { 3509 char *concatenated_name = alloca (strlen (namespace_name) + 2 3510 + strlen (name) + 1); 3511 3512 sprintf (concatenated_name, "%s::%s", namespace_name, name); 3513 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN); 3514 } 3515 3516 if (sym == NULL) 3517 return NULL; 3518 else if ((noside == EVAL_AVOID_SIDE_EFFECTS) 3519 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF)) 3520 result = allocate_value (SYMBOL_TYPE (sym)); 3521 else 3522 result = value_of_variable (sym, get_selected_block (0)); 3523 3524 if (result && want_address) 3525 result = value_addr (result); 3526 3527 return result; 3528 } 3529 3530 /* Given a pointer or a reference value V, find its real (RTTI) type. 3531 3532 Other parameters FULL, TOP, USING_ENC as with value_rtti_type() 3533 and refer to the values computed for the object pointed to. */ 3534 3535 struct type * 3536 value_rtti_indirect_type (struct value *v, int *full, 3537 int *top, int *using_enc) 3538 { 3539 struct value *target; 3540 struct type *type, *real_type, *target_type; 3541 3542 type = value_type (v); 3543 type = check_typedef (type); 3544 if (TYPE_CODE (type) == TYPE_CODE_REF) 3545 target = coerce_ref (v); 3546 else if (TYPE_CODE (type) == TYPE_CODE_PTR) 3547 target = value_ind (v); 3548 else 3549 return NULL; 3550 3551 real_type = value_rtti_type (target, full, top, using_enc); 3552 3553 if (real_type) 3554 { 3555 /* Copy qualifiers to the referenced object. */ 3556 target_type = value_type (target); 3557 real_type = make_cv_type (TYPE_CONST (target_type), 3558 TYPE_VOLATILE (target_type), real_type, NULL); 3559 if (TYPE_CODE (type) == TYPE_CODE_REF) 3560 real_type = lookup_reference_type (real_type); 3561 else if (TYPE_CODE (type) == TYPE_CODE_PTR) 3562 real_type = lookup_pointer_type (real_type); 3563 else 3564 internal_error (__FILE__, __LINE__, _("Unexpected value type.")); 3565 3566 /* Copy qualifiers to the pointer/reference. */ 3567 real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type), 3568 real_type, NULL); 3569 } 3570 3571 return real_type; 3572 } 3573 3574 /* Given a value pointed to by ARGP, check its real run-time type, and 3575 if that is different from the enclosing type, create a new value 3576 using the real run-time type as the enclosing type (and of the same 3577 type as ARGP) and return it, with the embedded offset adjusted to 3578 be the correct offset to the enclosed object. RTYPE is the type, 3579 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed 3580 by value_rtti_type(). If these are available, they can be supplied 3581 and a second call to value_rtti_type() is avoided. (Pass RTYPE == 3582 NULL if they're not available. */ 3583 3584 struct value * 3585 value_full_object (struct value *argp, 3586 struct type *rtype, 3587 int xfull, int xtop, 3588 int xusing_enc) 3589 { 3590 struct type *real_type; 3591 int full = 0; 3592 int top = -1; 3593 int using_enc = 0; 3594 struct value *new_val; 3595 3596 if (rtype) 3597 { 3598 real_type = rtype; 3599 full = xfull; 3600 top = xtop; 3601 using_enc = xusing_enc; 3602 } 3603 else 3604 real_type = value_rtti_type (argp, &full, &top, &using_enc); 3605 3606 /* If no RTTI data, or if object is already complete, do nothing. */ 3607 if (!real_type || real_type == value_enclosing_type (argp)) 3608 return argp; 3609 3610 /* In a destructor we might see a real type that is a superclass of 3611 the object's type. In this case it is better to leave the object 3612 as-is. */ 3613 if (full 3614 && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp))) 3615 return argp; 3616 3617 /* If we have the full object, but for some reason the enclosing 3618 type is wrong, set it. */ 3619 /* pai: FIXME -- sounds iffy */ 3620 if (full) 3621 { 3622 argp = value_copy (argp); 3623 set_value_enclosing_type (argp, real_type); 3624 return argp; 3625 } 3626 3627 /* Check if object is in memory. */ 3628 if (VALUE_LVAL (argp) != lval_memory) 3629 { 3630 warning (_("Couldn't retrieve complete object of RTTI " 3631 "type %s; object may be in register(s)."), 3632 TYPE_NAME (real_type)); 3633 3634 return argp; 3635 } 3636 3637 /* All other cases -- retrieve the complete object. */ 3638 /* Go back by the computed top_offset from the beginning of the 3639 object, adjusting for the embedded offset of argp if that's what 3640 value_rtti_type used for its computation. */ 3641 new_val = value_at_lazy (real_type, value_address (argp) - top + 3642 (using_enc ? 0 : value_embedded_offset (argp))); 3643 deprecated_set_value_type (new_val, value_type (argp)); 3644 set_value_embedded_offset (new_val, (using_enc 3645 ? top + value_embedded_offset (argp) 3646 : top)); 3647 return new_val; 3648 } 3649 3650 3651 /* Return the value of the local variable, if one exists. Throw error 3652 otherwise, such as if the request is made in an inappropriate context. */ 3653 3654 struct value * 3655 value_of_this (const struct language_defn *lang) 3656 { 3657 struct symbol *sym; 3658 struct block *b; 3659 struct frame_info *frame; 3660 3661 if (!lang->la_name_of_this) 3662 error (_("no `this' in current language")); 3663 3664 frame = get_selected_frame (_("no frame selected")); 3665 3666 b = get_frame_block (frame, NULL); 3667 3668 sym = lookup_language_this (lang, b); 3669 if (sym == NULL) 3670 error (_("current stack frame does not contain a variable named `%s'"), 3671 lang->la_name_of_this); 3672 3673 return read_var_value (sym, frame); 3674 } 3675 3676 /* Return the value of the local variable, if one exists. Return NULL 3677 otherwise. Never throw error. */ 3678 3679 struct value * 3680 value_of_this_silent (const struct language_defn *lang) 3681 { 3682 struct value *ret = NULL; 3683 volatile struct gdb_exception except; 3684 3685 TRY_CATCH (except, RETURN_MASK_ERROR) 3686 { 3687 ret = value_of_this (lang); 3688 } 3689 3690 return ret; 3691 } 3692 3693 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH 3694 elements long, starting at LOWBOUND. The result has the same lower 3695 bound as the original ARRAY. */ 3696 3697 struct value * 3698 value_slice (struct value *array, int lowbound, int length) 3699 { 3700 struct type *slice_range_type, *slice_type, *range_type; 3701 LONGEST lowerbound, upperbound; 3702 struct value *slice; 3703 struct type *array_type; 3704 3705 array_type = check_typedef (value_type (array)); 3706 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY 3707 && TYPE_CODE (array_type) != TYPE_CODE_STRING) 3708 error (_("cannot take slice of non-array")); 3709 3710 range_type = TYPE_INDEX_TYPE (array_type); 3711 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0) 3712 error (_("slice from bad array or bitstring")); 3713 3714 if (lowbound < lowerbound || length < 0 3715 || lowbound + length - 1 > upperbound) 3716 error (_("slice out of range")); 3717 3718 /* FIXME-type-allocation: need a way to free this type when we are 3719 done with it. */ 3720 slice_range_type = create_range_type ((struct type *) NULL, 3721 TYPE_TARGET_TYPE (range_type), 3722 lowbound, 3723 lowbound + length - 1); 3724 3725 { 3726 struct type *element_type = TYPE_TARGET_TYPE (array_type); 3727 LONGEST offset = 3728 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type)); 3729 3730 slice_type = create_array_type ((struct type *) NULL, 3731 element_type, 3732 slice_range_type); 3733 TYPE_CODE (slice_type) = TYPE_CODE (array_type); 3734 3735 if (VALUE_LVAL (array) == lval_memory && value_lazy (array)) 3736 slice = allocate_value_lazy (slice_type); 3737 else 3738 { 3739 slice = allocate_value (slice_type); 3740 value_contents_copy (slice, 0, array, offset, 3741 TYPE_LENGTH (slice_type)); 3742 } 3743 3744 set_value_component_location (slice, array); 3745 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array); 3746 set_value_offset (slice, value_offset (array) + offset); 3747 } 3748 return slice; 3749 } 3750 3751 /* Create a value for a FORTRAN complex number. Currently most of the 3752 time values are coerced to COMPLEX*16 (i.e. a complex number 3753 composed of 2 doubles. This really should be a smarter routine 3754 that figures out precision inteligently as opposed to assuming 3755 doubles. FIXME: fmb */ 3756 3757 struct value * 3758 value_literal_complex (struct value *arg1, 3759 struct value *arg2, 3760 struct type *type) 3761 { 3762 struct value *val; 3763 struct type *real_type = TYPE_TARGET_TYPE (type); 3764 3765 val = allocate_value (type); 3766 arg1 = value_cast (real_type, arg1); 3767 arg2 = value_cast (real_type, arg2); 3768 3769 memcpy (value_contents_raw (val), 3770 value_contents (arg1), TYPE_LENGTH (real_type)); 3771 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type), 3772 value_contents (arg2), TYPE_LENGTH (real_type)); 3773 return val; 3774 } 3775 3776 /* Cast a value into the appropriate complex data type. */ 3777 3778 static struct value * 3779 cast_into_complex (struct type *type, struct value *val) 3780 { 3781 struct type *real_type = TYPE_TARGET_TYPE (type); 3782 3783 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX) 3784 { 3785 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val)); 3786 struct value *re_val = allocate_value (val_real_type); 3787 struct value *im_val = allocate_value (val_real_type); 3788 3789 memcpy (value_contents_raw (re_val), 3790 value_contents (val), TYPE_LENGTH (val_real_type)); 3791 memcpy (value_contents_raw (im_val), 3792 value_contents (val) + TYPE_LENGTH (val_real_type), 3793 TYPE_LENGTH (val_real_type)); 3794 3795 return value_literal_complex (re_val, im_val, type); 3796 } 3797 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT 3798 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT) 3799 return value_literal_complex (val, 3800 value_zero (real_type, not_lval), 3801 type); 3802 else 3803 error (_("cannot cast non-number to complex")); 3804 } 3805 3806 void 3807 _initialize_valops (void) 3808 { 3809 add_setshow_boolean_cmd ("overload-resolution", class_support, 3810 &overload_resolution, _("\ 3811 Set overload resolution in evaluating C++ functions."), _("\ 3812 Show overload resolution in evaluating C++ functions."), 3813 NULL, NULL, 3814 show_overload_resolution, 3815 &setlist, &showlist); 3816 overload_resolution = 1; 3817 } 3818