1 /* Perform non-arithmetic operations on values, for GDB. 2 3 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 4 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 5 2008, 2009, 2010 Free Software Foundation, Inc. 6 7 This file is part of GDB. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 21 22 #include "defs.h" 23 #include "symtab.h" 24 #include "gdbtypes.h" 25 #include "value.h" 26 #include "frame.h" 27 #include "inferior.h" 28 #include "gdbcore.h" 29 #include "target.h" 30 #include "demangle.h" 31 #include "language.h" 32 #include "gdbcmd.h" 33 #include "regcache.h" 34 #include "cp-abi.h" 35 #include "block.h" 36 #include "infcall.h" 37 #include "dictionary.h" 38 #include "cp-support.h" 39 #include "dfp.h" 40 #include "user-regs.h" 41 42 #include <errno.h> 43 #include "gdb_string.h" 44 #include "gdb_assert.h" 45 #include "cp-support.h" 46 #include "observer.h" 47 #include "objfiles.h" 48 #include "symtab.h" 49 50 extern int overload_debug; 51 /* Local functions. */ 52 53 static int typecmp (int staticp, int varargs, int nargs, 54 struct field t1[], struct value *t2[]); 55 56 static struct value *search_struct_field (const char *, struct value *, 57 int, struct type *, int); 58 59 static struct value *search_struct_method (const char *, struct value **, 60 struct value **, 61 int, int *, struct type *); 62 63 static int find_oload_champ_namespace (struct type **, int, 64 const char *, const char *, 65 struct symbol ***, 66 struct badness_vector **, 67 const int no_adl); 68 69 static 70 int find_oload_champ_namespace_loop (struct type **, int, 71 const char *, const char *, 72 int, struct symbol ***, 73 struct badness_vector **, int *, 74 const int no_adl); 75 76 static int find_oload_champ (struct type **, int, int, int, 77 struct fn_field *, struct symbol **, 78 struct badness_vector **); 79 80 static int oload_method_static (int, struct fn_field *, int); 81 82 enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE }; 83 84 static enum 85 oload_classification classify_oload_match (struct badness_vector *, 86 int, int); 87 88 static struct value *value_struct_elt_for_reference (struct type *, 89 int, struct type *, 90 char *, 91 struct type *, 92 int, enum noside); 93 94 static struct value *value_namespace_elt (const struct type *, 95 char *, int , enum noside); 96 97 static struct value *value_maybe_namespace_elt (const struct type *, 98 char *, int, 99 enum noside); 100 101 static CORE_ADDR allocate_space_in_inferior (int); 102 103 static struct value *cast_into_complex (struct type *, struct value *); 104 105 static struct fn_field *find_method_list (struct value **, const char *, 106 int, struct type *, int *, 107 struct type **, int *); 108 109 void _initialize_valops (void); 110 111 #if 0 112 /* Flag for whether we want to abandon failed expression evals by 113 default. */ 114 115 static int auto_abandon = 0; 116 #endif 117 118 int overload_resolution = 0; 119 static void 120 show_overload_resolution (struct ui_file *file, int from_tty, 121 struct cmd_list_element *c, 122 const char *value) 123 { 124 fprintf_filtered (file, _("\ 125 Overload resolution in evaluating C++ functions is %s.\n"), 126 value); 127 } 128 129 /* Find the address of function name NAME in the inferior. If OBJF_P 130 is non-NULL, *OBJF_P will be set to the OBJFILE where the function 131 is defined. */ 132 133 struct value * 134 find_function_in_inferior (const char *name, struct objfile **objf_p) 135 { 136 struct symbol *sym; 137 138 sym = lookup_symbol (name, 0, VAR_DOMAIN, 0); 139 if (sym != NULL) 140 { 141 if (SYMBOL_CLASS (sym) != LOC_BLOCK) 142 { 143 error (_("\"%s\" exists in this program but is not a function."), 144 name); 145 } 146 147 if (objf_p) 148 *objf_p = SYMBOL_SYMTAB (sym)->objfile; 149 150 return value_of_variable (sym, NULL); 151 } 152 else 153 { 154 struct minimal_symbol *msymbol = 155 lookup_minimal_symbol (name, NULL, NULL); 156 157 if (msymbol != NULL) 158 { 159 struct objfile *objfile = msymbol_objfile (msymbol); 160 struct gdbarch *gdbarch = get_objfile_arch (objfile); 161 162 struct type *type; 163 CORE_ADDR maddr; 164 type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char); 165 type = lookup_function_type (type); 166 type = lookup_pointer_type (type); 167 maddr = SYMBOL_VALUE_ADDRESS (msymbol); 168 169 if (objf_p) 170 *objf_p = objfile; 171 172 return value_from_pointer (type, maddr); 173 } 174 else 175 { 176 if (!target_has_execution) 177 error (_("evaluation of this expression requires the target program to be active")); 178 else 179 error (_("evaluation of this expression requires the program to have a function \"%s\"."), name); 180 } 181 } 182 } 183 184 /* Allocate NBYTES of space in the inferior using the inferior's 185 malloc and return a value that is a pointer to the allocated 186 space. */ 187 188 struct value * 189 value_allocate_space_in_inferior (int len) 190 { 191 struct objfile *objf; 192 struct value *val = find_function_in_inferior ("malloc", &objf); 193 struct gdbarch *gdbarch = get_objfile_arch (objf); 194 struct value *blocklen; 195 196 blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len); 197 val = call_function_by_hand (val, 1, &blocklen); 198 if (value_logical_not (val)) 199 { 200 if (!target_has_execution) 201 error (_("No memory available to program now: you need to start the target first")); 202 else 203 error (_("No memory available to program: call to malloc failed")); 204 } 205 return val; 206 } 207 208 static CORE_ADDR 209 allocate_space_in_inferior (int len) 210 { 211 return value_as_long (value_allocate_space_in_inferior (len)); 212 } 213 214 /* Cast struct value VAL to type TYPE and return as a value. 215 Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION 216 for this to work. Typedef to one of the codes is permitted. 217 Returns NULL if the cast is neither an upcast nor a downcast. */ 218 219 static struct value * 220 value_cast_structs (struct type *type, struct value *v2) 221 { 222 struct type *t1; 223 struct type *t2; 224 struct value *v; 225 226 gdb_assert (type != NULL && v2 != NULL); 227 228 t1 = check_typedef (type); 229 t2 = check_typedef (value_type (v2)); 230 231 /* Check preconditions. */ 232 gdb_assert ((TYPE_CODE (t1) == TYPE_CODE_STRUCT 233 || TYPE_CODE (t1) == TYPE_CODE_UNION) 234 && !!"Precondition is that type is of STRUCT or UNION kind."); 235 gdb_assert ((TYPE_CODE (t2) == TYPE_CODE_STRUCT 236 || TYPE_CODE (t2) == TYPE_CODE_UNION) 237 && !!"Precondition is that value is of STRUCT or UNION kind"); 238 239 if (TYPE_NAME (t1) != NULL 240 && TYPE_NAME (t2) != NULL 241 && !strcmp (TYPE_NAME (t1), TYPE_NAME (t2))) 242 return NULL; 243 244 /* Upcasting: look in the type of the source to see if it contains the 245 type of the target as a superclass. If so, we'll need to 246 offset the pointer rather than just change its type. */ 247 if (TYPE_NAME (t1) != NULL) 248 { 249 v = search_struct_field (type_name_no_tag (t1), 250 v2, 0, t2, 1); 251 if (v) 252 return v; 253 } 254 255 /* Downcasting: look in the type of the target to see if it contains the 256 type of the source as a superclass. If so, we'll need to 257 offset the pointer rather than just change its type. */ 258 if (TYPE_NAME (t2) != NULL) 259 { 260 /* Try downcasting using the run-time type of the value. */ 261 int full, top, using_enc; 262 struct type *real_type; 263 264 real_type = value_rtti_type (v2, &full, &top, &using_enc); 265 if (real_type) 266 { 267 v = value_full_object (v2, real_type, full, top, using_enc); 268 v = value_at_lazy (real_type, value_address (v)); 269 270 /* We might be trying to cast to the outermost enclosing 271 type, in which case search_struct_field won't work. */ 272 if (TYPE_NAME (real_type) != NULL 273 && !strcmp (TYPE_NAME (real_type), TYPE_NAME (t1))) 274 return v; 275 276 v = search_struct_field (type_name_no_tag (t2), v, 0, real_type, 1); 277 if (v) 278 return v; 279 } 280 281 /* Try downcasting using information from the destination type 282 T2. This wouldn't work properly for classes with virtual 283 bases, but those were handled above. */ 284 v = search_struct_field (type_name_no_tag (t2), 285 value_zero (t1, not_lval), 0, t1, 1); 286 if (v) 287 { 288 /* Downcasting is possible (t1 is superclass of v2). */ 289 CORE_ADDR addr2 = value_address (v2); 290 291 addr2 -= value_address (v) + value_embedded_offset (v); 292 return value_at (type, addr2); 293 } 294 } 295 296 return NULL; 297 } 298 299 /* Cast one pointer or reference type to another. Both TYPE and 300 the type of ARG2 should be pointer types, or else both should be 301 reference types. Returns the new pointer or reference. */ 302 303 struct value * 304 value_cast_pointers (struct type *type, struct value *arg2) 305 { 306 struct type *type1 = check_typedef (type); 307 struct type *type2 = check_typedef (value_type (arg2)); 308 struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1)); 309 struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2)); 310 311 if (TYPE_CODE (t1) == TYPE_CODE_STRUCT 312 && TYPE_CODE (t2) == TYPE_CODE_STRUCT 313 && !value_logical_not (arg2)) 314 { 315 struct value *v2; 316 317 if (TYPE_CODE (type2) == TYPE_CODE_REF) 318 v2 = coerce_ref (arg2); 319 else 320 v2 = value_ind (arg2); 321 gdb_assert (TYPE_CODE (check_typedef (value_type (v2))) == TYPE_CODE_STRUCT 322 && !!"Why did coercion fail?"); 323 v2 = value_cast_structs (t1, v2); 324 /* At this point we have what we can have, un-dereference if needed. */ 325 if (v2) 326 { 327 struct value *v = value_addr (v2); 328 329 deprecated_set_value_type (v, type); 330 return v; 331 } 332 } 333 334 /* No superclass found, just change the pointer type. */ 335 arg2 = value_copy (arg2); 336 deprecated_set_value_type (arg2, type); 337 arg2 = value_change_enclosing_type (arg2, type); 338 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */ 339 return arg2; 340 } 341 342 /* Cast value ARG2 to type TYPE and return as a value. 343 More general than a C cast: accepts any two types of the same length, 344 and if ARG2 is an lvalue it can be cast into anything at all. */ 345 /* In C++, casts may change pointer or object representations. */ 346 347 struct value * 348 value_cast (struct type *type, struct value *arg2) 349 { 350 enum type_code code1; 351 enum type_code code2; 352 int scalar; 353 struct type *type2; 354 355 int convert_to_boolean = 0; 356 357 if (value_type (arg2) == type) 358 return arg2; 359 360 code1 = TYPE_CODE (check_typedef (type)); 361 362 /* Check if we are casting struct reference to struct reference. */ 363 if (code1 == TYPE_CODE_REF) 364 { 365 /* We dereference type; then we recurse and finally 366 we generate value of the given reference. Nothing wrong with 367 that. */ 368 struct type *t1 = check_typedef (type); 369 struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1)); 370 struct value *val = value_cast (dereftype, arg2); 371 372 return value_ref (val); 373 } 374 375 code2 = TYPE_CODE (check_typedef (value_type (arg2))); 376 377 if (code2 == TYPE_CODE_REF) 378 /* We deref the value and then do the cast. */ 379 return value_cast (type, coerce_ref (arg2)); 380 381 CHECK_TYPEDEF (type); 382 code1 = TYPE_CODE (type); 383 arg2 = coerce_ref (arg2); 384 type2 = check_typedef (value_type (arg2)); 385 386 /* You can't cast to a reference type. See value_cast_pointers 387 instead. */ 388 gdb_assert (code1 != TYPE_CODE_REF); 389 390 /* A cast to an undetermined-length array_type, such as 391 (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT, 392 where N is sizeof(OBJECT)/sizeof(TYPE). */ 393 if (code1 == TYPE_CODE_ARRAY) 394 { 395 struct type *element_type = TYPE_TARGET_TYPE (type); 396 unsigned element_length = TYPE_LENGTH (check_typedef (element_type)); 397 398 if (element_length > 0 && TYPE_ARRAY_UPPER_BOUND_IS_UNDEFINED (type)) 399 { 400 struct type *range_type = TYPE_INDEX_TYPE (type); 401 int val_length = TYPE_LENGTH (type2); 402 LONGEST low_bound, high_bound, new_length; 403 404 if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0) 405 low_bound = 0, high_bound = 0; 406 new_length = val_length / element_length; 407 if (val_length % element_length != 0) 408 warning (_("array element type size does not divide object size in cast")); 409 /* FIXME-type-allocation: need a way to free this type when 410 we are done with it. */ 411 range_type = create_range_type ((struct type *) NULL, 412 TYPE_TARGET_TYPE (range_type), 413 low_bound, 414 new_length + low_bound - 1); 415 deprecated_set_value_type (arg2, 416 create_array_type ((struct type *) NULL, 417 element_type, 418 range_type)); 419 return arg2; 420 } 421 } 422 423 if (current_language->c_style_arrays 424 && TYPE_CODE (type2) == TYPE_CODE_ARRAY) 425 arg2 = value_coerce_array (arg2); 426 427 if (TYPE_CODE (type2) == TYPE_CODE_FUNC) 428 arg2 = value_coerce_function (arg2); 429 430 type2 = check_typedef (value_type (arg2)); 431 code2 = TYPE_CODE (type2); 432 433 if (code1 == TYPE_CODE_COMPLEX) 434 return cast_into_complex (type, arg2); 435 if (code1 == TYPE_CODE_BOOL) 436 { 437 code1 = TYPE_CODE_INT; 438 convert_to_boolean = 1; 439 } 440 if (code1 == TYPE_CODE_CHAR) 441 code1 = TYPE_CODE_INT; 442 if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR) 443 code2 = TYPE_CODE_INT; 444 445 scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT 446 || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM 447 || code2 == TYPE_CODE_RANGE); 448 449 if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION) 450 && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION) 451 && TYPE_NAME (type) != 0) 452 { 453 struct value *v = value_cast_structs (type, arg2); 454 455 if (v) 456 return v; 457 } 458 459 if (code1 == TYPE_CODE_FLT && scalar) 460 return value_from_double (type, value_as_double (arg2)); 461 else if (code1 == TYPE_CODE_DECFLOAT && scalar) 462 { 463 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); 464 int dec_len = TYPE_LENGTH (type); 465 gdb_byte dec[16]; 466 467 if (code2 == TYPE_CODE_FLT) 468 decimal_from_floating (arg2, dec, dec_len, byte_order); 469 else if (code2 == TYPE_CODE_DECFLOAT) 470 decimal_convert (value_contents (arg2), TYPE_LENGTH (type2), 471 byte_order, dec, dec_len, byte_order); 472 else 473 /* The only option left is an integral type. */ 474 decimal_from_integral (arg2, dec, dec_len, byte_order); 475 476 return value_from_decfloat (type, dec); 477 } 478 else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM 479 || code1 == TYPE_CODE_RANGE) 480 && (scalar || code2 == TYPE_CODE_PTR 481 || code2 == TYPE_CODE_MEMBERPTR)) 482 { 483 LONGEST longest; 484 485 /* When we cast pointers to integers, we mustn't use 486 gdbarch_pointer_to_address to find the address the pointer 487 represents, as value_as_long would. GDB should evaluate 488 expressions just as the compiler would --- and the compiler 489 sees a cast as a simple reinterpretation of the pointer's 490 bits. */ 491 if (code2 == TYPE_CODE_PTR) 492 longest = extract_unsigned_integer 493 (value_contents (arg2), TYPE_LENGTH (type2), 494 gdbarch_byte_order (get_type_arch (type2))); 495 else 496 longest = value_as_long (arg2); 497 return value_from_longest (type, convert_to_boolean ? 498 (LONGEST) (longest ? 1 : 0) : longest); 499 } 500 else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT 501 || code2 == TYPE_CODE_ENUM 502 || code2 == TYPE_CODE_RANGE)) 503 { 504 /* TYPE_LENGTH (type) is the length of a pointer, but we really 505 want the length of an address! -- we are really dealing with 506 addresses (i.e., gdb representations) not pointers (i.e., 507 target representations) here. 508 509 This allows things like "print *(int *)0x01000234" to work 510 without printing a misleading message -- which would 511 otherwise occur when dealing with a target having two byte 512 pointers and four byte addresses. */ 513 514 int addr_bit = gdbarch_addr_bit (get_type_arch (type2)); 515 LONGEST longest = value_as_long (arg2); 516 517 if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT) 518 { 519 if (longest >= ((LONGEST) 1 << addr_bit) 520 || longest <= -((LONGEST) 1 << addr_bit)) 521 warning (_("value truncated")); 522 } 523 return value_from_longest (type, longest); 524 } 525 else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT 526 && value_as_long (arg2) == 0) 527 { 528 struct value *result = allocate_value (type); 529 530 cplus_make_method_ptr (type, value_contents_writeable (result), 0, 0); 531 return result; 532 } 533 else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT 534 && value_as_long (arg2) == 0) 535 { 536 /* The Itanium C++ ABI represents NULL pointers to members as 537 minus one, instead of biasing the normal case. */ 538 return value_from_longest (type, -1); 539 } 540 else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2)) 541 { 542 if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR) 543 return value_cast_pointers (type, arg2); 544 545 arg2 = value_copy (arg2); 546 deprecated_set_value_type (arg2, type); 547 arg2 = value_change_enclosing_type (arg2, type); 548 set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */ 549 return arg2; 550 } 551 else if (VALUE_LVAL (arg2) == lval_memory) 552 return value_at_lazy (type, value_address (arg2)); 553 else if (code1 == TYPE_CODE_VOID) 554 { 555 return value_zero (type, not_lval); 556 } 557 else 558 { 559 error (_("Invalid cast.")); 560 return 0; 561 } 562 } 563 564 /* The C++ reinterpret_cast operator. */ 565 566 struct value * 567 value_reinterpret_cast (struct type *type, struct value *arg) 568 { 569 struct value *result; 570 struct type *real_type = check_typedef (type); 571 struct type *arg_type, *dest_type; 572 int is_ref = 0; 573 enum type_code dest_code, arg_code; 574 575 /* Do reference, function, and array conversion. */ 576 arg = coerce_array (arg); 577 578 /* Attempt to preserve the type the user asked for. */ 579 dest_type = type; 580 581 /* If we are casting to a reference type, transform 582 reinterpret_cast<T&>(V) to *reinterpret_cast<T*>(&V). */ 583 if (TYPE_CODE (real_type) == TYPE_CODE_REF) 584 { 585 is_ref = 1; 586 arg = value_addr (arg); 587 dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type)); 588 real_type = lookup_pointer_type (real_type); 589 } 590 591 arg_type = value_type (arg); 592 593 dest_code = TYPE_CODE (real_type); 594 arg_code = TYPE_CODE (arg_type); 595 596 /* We can convert pointer types, or any pointer type to int, or int 597 type to pointer. */ 598 if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT) 599 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR) 600 || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT) 601 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR) 602 || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT) 603 || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR) 604 || (dest_code == arg_code 605 && (dest_code == TYPE_CODE_PTR 606 || dest_code == TYPE_CODE_METHODPTR 607 || dest_code == TYPE_CODE_MEMBERPTR))) 608 result = value_cast (dest_type, arg); 609 else 610 error (_("Invalid reinterpret_cast")); 611 612 if (is_ref) 613 result = value_cast (type, value_ref (value_ind (result))); 614 615 return result; 616 } 617 618 /* A helper for value_dynamic_cast. This implements the first of two 619 runtime checks: we iterate over all the base classes of the value's 620 class which are equal to the desired class; if only one of these 621 holds the value, then it is the answer. */ 622 623 static int 624 dynamic_cast_check_1 (struct type *desired_type, 625 const bfd_byte *contents, 626 CORE_ADDR address, 627 struct type *search_type, 628 CORE_ADDR arg_addr, 629 struct type *arg_type, 630 struct value **result) 631 { 632 int i, result_count = 0; 633 634 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i) 635 { 636 int offset = baseclass_offset (search_type, i, contents, address); 637 638 if (offset == -1) 639 error (_("virtual baseclass botch")); 640 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i))) 641 { 642 if (address + offset >= arg_addr 643 && address + offset < arg_addr + TYPE_LENGTH (arg_type)) 644 { 645 ++result_count; 646 if (!*result) 647 *result = value_at_lazy (TYPE_BASECLASS (search_type, i), 648 address + offset); 649 } 650 } 651 else 652 result_count += dynamic_cast_check_1 (desired_type, 653 contents + offset, 654 address + offset, 655 TYPE_BASECLASS (search_type, i), 656 arg_addr, 657 arg_type, 658 result); 659 } 660 661 return result_count; 662 } 663 664 /* A helper for value_dynamic_cast. This implements the second of two 665 runtime checks: we look for a unique public sibling class of the 666 argument's declared class. */ 667 668 static int 669 dynamic_cast_check_2 (struct type *desired_type, 670 const bfd_byte *contents, 671 CORE_ADDR address, 672 struct type *search_type, 673 struct value **result) 674 { 675 int i, result_count = 0; 676 677 for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i) 678 { 679 int offset; 680 681 if (! BASETYPE_VIA_PUBLIC (search_type, i)) 682 continue; 683 684 offset = baseclass_offset (search_type, i, contents, address); 685 if (offset == -1) 686 error (_("virtual baseclass botch")); 687 if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i))) 688 { 689 ++result_count; 690 if (*result == NULL) 691 *result = value_at_lazy (TYPE_BASECLASS (search_type, i), 692 address + offset); 693 } 694 else 695 result_count += dynamic_cast_check_2 (desired_type, 696 contents + offset, 697 address + offset, 698 TYPE_BASECLASS (search_type, i), 699 result); 700 } 701 702 return result_count; 703 } 704 705 /* The C++ dynamic_cast operator. */ 706 707 struct value * 708 value_dynamic_cast (struct type *type, struct value *arg) 709 { 710 int full, top, using_enc; 711 struct type *resolved_type = check_typedef (type); 712 struct type *arg_type = check_typedef (value_type (arg)); 713 struct type *class_type, *rtti_type; 714 struct value *result, *tem, *original_arg = arg; 715 CORE_ADDR addr; 716 int is_ref = TYPE_CODE (resolved_type) == TYPE_CODE_REF; 717 718 if (TYPE_CODE (resolved_type) != TYPE_CODE_PTR 719 && TYPE_CODE (resolved_type) != TYPE_CODE_REF) 720 error (_("Argument to dynamic_cast must be a pointer or reference type")); 721 if (TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_VOID 722 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) != TYPE_CODE_CLASS) 723 error (_("Argument to dynamic_cast must be pointer to class or `void *'")); 724 725 class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type)); 726 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR) 727 { 728 if (TYPE_CODE (arg_type) != TYPE_CODE_PTR 729 && ! (TYPE_CODE (arg_type) == TYPE_CODE_INT 730 && value_as_long (arg) == 0)) 731 error (_("Argument to dynamic_cast does not have pointer type")); 732 if (TYPE_CODE (arg_type) == TYPE_CODE_PTR) 733 { 734 arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type)); 735 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS) 736 error (_("Argument to dynamic_cast does not have pointer to class type")); 737 } 738 739 /* Handle NULL pointers. */ 740 if (value_as_long (arg) == 0) 741 return value_zero (type, not_lval); 742 743 arg = value_ind (arg); 744 } 745 else 746 { 747 if (TYPE_CODE (arg_type) != TYPE_CODE_CLASS) 748 error (_("Argument to dynamic_cast does not have class type")); 749 } 750 751 /* If the classes are the same, just return the argument. */ 752 if (class_types_same_p (class_type, arg_type)) 753 return value_cast (type, arg); 754 755 /* If the target type is a unique base class of the argument's 756 declared type, just cast it. */ 757 if (is_ancestor (class_type, arg_type)) 758 { 759 if (is_unique_ancestor (class_type, arg)) 760 return value_cast (type, original_arg); 761 error (_("Ambiguous dynamic_cast")); 762 } 763 764 rtti_type = value_rtti_type (arg, &full, &top, &using_enc); 765 if (! rtti_type) 766 error (_("Couldn't determine value's most derived type for dynamic_cast")); 767 768 /* Compute the most derived object's address. */ 769 addr = value_address (arg); 770 if (full) 771 { 772 /* Done. */ 773 } 774 else if (using_enc) 775 addr += top; 776 else 777 addr += top + value_embedded_offset (arg); 778 779 /* dynamic_cast<void *> means to return a pointer to the 780 most-derived object. */ 781 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR 782 && TYPE_CODE (TYPE_TARGET_TYPE (resolved_type)) == TYPE_CODE_VOID) 783 return value_at_lazy (type, addr); 784 785 tem = value_at (type, addr); 786 787 /* The first dynamic check specified in 5.2.7. */ 788 if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type))) 789 { 790 if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type))) 791 return tem; 792 result = NULL; 793 if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type), 794 value_contents (tem), value_address (tem), 795 rtti_type, addr, 796 arg_type, 797 &result) == 1) 798 return value_cast (type, 799 is_ref ? value_ref (result) : value_addr (result)); 800 } 801 802 /* The second dynamic check specified in 5.2.7. */ 803 result = NULL; 804 if (is_public_ancestor (arg_type, rtti_type) 805 && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type), 806 value_contents (tem), value_address (tem), 807 rtti_type, &result) == 1) 808 return value_cast (type, 809 is_ref ? value_ref (result) : value_addr (result)); 810 811 if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR) 812 return value_zero (type, not_lval); 813 814 error (_("dynamic_cast failed")); 815 } 816 817 /* Create a value of type TYPE that is zero, and return it. */ 818 819 struct value * 820 value_zero (struct type *type, enum lval_type lv) 821 { 822 struct value *val = allocate_value (type); 823 824 VALUE_LVAL (val) = lv; 825 return val; 826 } 827 828 /* Create a value of numeric type TYPE that is one, and return it. */ 829 830 struct value * 831 value_one (struct type *type, enum lval_type lv) 832 { 833 struct type *type1 = check_typedef (type); 834 struct value *val; 835 836 if (TYPE_CODE (type1) == TYPE_CODE_DECFLOAT) 837 { 838 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); 839 gdb_byte v[16]; 840 841 decimal_from_string (v, TYPE_LENGTH (type), byte_order, "1"); 842 val = value_from_decfloat (type, v); 843 } 844 else if (TYPE_CODE (type1) == TYPE_CODE_FLT) 845 { 846 val = value_from_double (type, (DOUBLEST) 1); 847 } 848 else if (is_integral_type (type1)) 849 { 850 val = value_from_longest (type, (LONGEST) 1); 851 } 852 else 853 { 854 error (_("Not a numeric type.")); 855 } 856 857 VALUE_LVAL (val) = lv; 858 return val; 859 } 860 861 /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack. */ 862 863 static struct value * 864 get_value_at (struct type *type, CORE_ADDR addr, int lazy) 865 { 866 struct value *val; 867 868 if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID) 869 error (_("Attempt to dereference a generic pointer.")); 870 871 if (lazy) 872 { 873 val = allocate_value_lazy (type); 874 } 875 else 876 { 877 val = allocate_value (type); 878 read_memory (addr, value_contents_all_raw (val), TYPE_LENGTH (type)); 879 } 880 881 VALUE_LVAL (val) = lval_memory; 882 set_value_address (val, addr); 883 884 return val; 885 } 886 887 /* Return a value with type TYPE located at ADDR. 888 889 Call value_at only if the data needs to be fetched immediately; 890 if we can be 'lazy' and defer the fetch, perhaps indefinately, call 891 value_at_lazy instead. value_at_lazy simply records the address of 892 the data and sets the lazy-evaluation-required flag. The lazy flag 893 is tested in the value_contents macro, which is used if and when 894 the contents are actually required. 895 896 Note: value_at does *NOT* handle embedded offsets; perform such 897 adjustments before or after calling it. */ 898 899 struct value * 900 value_at (struct type *type, CORE_ADDR addr) 901 { 902 return get_value_at (type, addr, 0); 903 } 904 905 /* Return a lazy value with type TYPE located at ADDR (cf. value_at). */ 906 907 struct value * 908 value_at_lazy (struct type *type, CORE_ADDR addr) 909 { 910 return get_value_at (type, addr, 1); 911 } 912 913 /* Called only from the value_contents and value_contents_all() 914 macros, if the current data for a variable needs to be loaded into 915 value_contents(VAL). Fetches the data from the user's process, and 916 clears the lazy flag to indicate that the data in the buffer is 917 valid. 918 919 If the value is zero-length, we avoid calling read_memory, which 920 would abort. We mark the value as fetched anyway -- all 0 bytes of 921 it. 922 923 This function returns a value because it is used in the 924 value_contents macro as part of an expression, where a void would 925 not work. The value is ignored. */ 926 927 int 928 value_fetch_lazy (struct value *val) 929 { 930 gdb_assert (value_lazy (val)); 931 allocate_value_contents (val); 932 if (value_bitsize (val)) 933 { 934 /* To read a lazy bitfield, read the entire enclosing value. This 935 prevents reading the same block of (possibly volatile) memory once 936 per bitfield. It would be even better to read only the containing 937 word, but we have no way to record that just specific bits of a 938 value have been fetched. */ 939 struct type *type = check_typedef (value_type (val)); 940 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type)); 941 struct value *parent = value_parent (val); 942 LONGEST offset = value_offset (val); 943 LONGEST num = unpack_bits_as_long (value_type (val), 944 (value_contents_for_printing (parent) 945 + offset), 946 value_bitpos (val), 947 value_bitsize (val)); 948 int length = TYPE_LENGTH (type); 949 950 if (!value_bits_valid (val, 951 TARGET_CHAR_BIT * offset + value_bitpos (val), 952 value_bitsize (val))) 953 error (_("value has been optimized out")); 954 955 store_signed_integer (value_contents_raw (val), length, byte_order, num); 956 } 957 else if (VALUE_LVAL (val) == lval_memory) 958 { 959 CORE_ADDR addr = value_address (val); 960 int length = TYPE_LENGTH (check_typedef (value_enclosing_type (val))); 961 962 if (length) 963 { 964 if (value_stack (val)) 965 read_stack (addr, value_contents_all_raw (val), length); 966 else 967 read_memory (addr, value_contents_all_raw (val), length); 968 } 969 } 970 else if (VALUE_LVAL (val) == lval_register) 971 { 972 struct frame_info *frame; 973 int regnum; 974 struct type *type = check_typedef (value_type (val)); 975 struct value *new_val = val, *mark = value_mark (); 976 977 /* Offsets are not supported here; lazy register values must 978 refer to the entire register. */ 979 gdb_assert (value_offset (val) == 0); 980 981 while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val)) 982 { 983 frame = frame_find_by_id (VALUE_FRAME_ID (new_val)); 984 regnum = VALUE_REGNUM (new_val); 985 986 gdb_assert (frame != NULL); 987 988 /* Convertible register routines are used for multi-register 989 values and for interpretation in different types 990 (e.g. float or int from a double register). Lazy 991 register values should have the register's natural type, 992 so they do not apply. */ 993 gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame), 994 regnum, type)); 995 996 new_val = get_frame_register_value (frame, regnum); 997 } 998 999 /* If it's still lazy (for instance, a saved register on the 1000 stack), fetch it. */ 1001 if (value_lazy (new_val)) 1002 value_fetch_lazy (new_val); 1003 1004 /* If the register was not saved, mark it unavailable. */ 1005 if (value_optimized_out (new_val)) 1006 set_value_optimized_out (val, 1); 1007 else 1008 memcpy (value_contents_raw (val), value_contents (new_val), 1009 TYPE_LENGTH (type)); 1010 1011 if (frame_debug) 1012 { 1013 struct gdbarch *gdbarch; 1014 frame = frame_find_by_id (VALUE_FRAME_ID (val)); 1015 regnum = VALUE_REGNUM (val); 1016 gdbarch = get_frame_arch (frame); 1017 1018 fprintf_unfiltered (gdb_stdlog, "\ 1019 { value_fetch_lazy (frame=%d,regnum=%d(%s),...) ", 1020 frame_relative_level (frame), regnum, 1021 user_reg_map_regnum_to_name (gdbarch, regnum)); 1022 1023 fprintf_unfiltered (gdb_stdlog, "->"); 1024 if (value_optimized_out (new_val)) 1025 fprintf_unfiltered (gdb_stdlog, " optimized out"); 1026 else 1027 { 1028 int i; 1029 const gdb_byte *buf = value_contents (new_val); 1030 1031 if (VALUE_LVAL (new_val) == lval_register) 1032 fprintf_unfiltered (gdb_stdlog, " register=%d", 1033 VALUE_REGNUM (new_val)); 1034 else if (VALUE_LVAL (new_val) == lval_memory) 1035 fprintf_unfiltered (gdb_stdlog, " address=%s", 1036 paddress (gdbarch, 1037 value_address (new_val))); 1038 else 1039 fprintf_unfiltered (gdb_stdlog, " computed"); 1040 1041 fprintf_unfiltered (gdb_stdlog, " bytes="); 1042 fprintf_unfiltered (gdb_stdlog, "["); 1043 for (i = 0; i < register_size (gdbarch, regnum); i++) 1044 fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]); 1045 fprintf_unfiltered (gdb_stdlog, "]"); 1046 } 1047 1048 fprintf_unfiltered (gdb_stdlog, " }\n"); 1049 } 1050 1051 /* Dispose of the intermediate values. This prevents 1052 watchpoints from trying to watch the saved frame pointer. */ 1053 value_free_to_mark (mark); 1054 } 1055 else if (VALUE_LVAL (val) == lval_computed) 1056 value_computed_funcs (val)->read (val); 1057 else 1058 internal_error (__FILE__, __LINE__, "Unexpected lazy value type."); 1059 1060 set_value_lazy (val, 0); 1061 return 0; 1062 } 1063 1064 1065 /* Store the contents of FROMVAL into the location of TOVAL. 1066 Return a new value with the location of TOVAL and contents of FROMVAL. */ 1067 1068 struct value * 1069 value_assign (struct value *toval, struct value *fromval) 1070 { 1071 struct type *type; 1072 struct value *val; 1073 struct frame_id old_frame; 1074 1075 if (!deprecated_value_modifiable (toval)) 1076 error (_("Left operand of assignment is not a modifiable lvalue.")); 1077 1078 toval = coerce_ref (toval); 1079 1080 type = value_type (toval); 1081 if (VALUE_LVAL (toval) != lval_internalvar) 1082 { 1083 toval = value_coerce_to_target (toval); 1084 fromval = value_cast (type, fromval); 1085 } 1086 else 1087 { 1088 /* Coerce arrays and functions to pointers, except for arrays 1089 which only live in GDB's storage. */ 1090 if (!value_must_coerce_to_target (fromval)) 1091 fromval = coerce_array (fromval); 1092 } 1093 1094 CHECK_TYPEDEF (type); 1095 1096 /* Since modifying a register can trash the frame chain, and 1097 modifying memory can trash the frame cache, we save the old frame 1098 and then restore the new frame afterwards. */ 1099 old_frame = get_frame_id (deprecated_safe_get_selected_frame ()); 1100 1101 switch (VALUE_LVAL (toval)) 1102 { 1103 case lval_internalvar: 1104 set_internalvar (VALUE_INTERNALVAR (toval), fromval); 1105 val = value_copy (fromval); 1106 val = value_change_enclosing_type (val, 1107 value_enclosing_type (fromval)); 1108 set_value_embedded_offset (val, value_embedded_offset (fromval)); 1109 set_value_pointed_to_offset (val, 1110 value_pointed_to_offset (fromval)); 1111 return val; 1112 1113 case lval_internalvar_component: 1114 set_internalvar_component (VALUE_INTERNALVAR (toval), 1115 value_offset (toval), 1116 value_bitpos (toval), 1117 value_bitsize (toval), 1118 fromval); 1119 break; 1120 1121 case lval_memory: 1122 { 1123 const gdb_byte *dest_buffer; 1124 CORE_ADDR changed_addr; 1125 int changed_len; 1126 gdb_byte buffer[sizeof (LONGEST)]; 1127 1128 if (value_bitsize (toval)) 1129 { 1130 struct value *parent = value_parent (toval); 1131 1132 changed_addr = value_address (parent) + value_offset (toval); 1133 changed_len = (value_bitpos (toval) 1134 + value_bitsize (toval) 1135 + HOST_CHAR_BIT - 1) 1136 / HOST_CHAR_BIT; 1137 1138 /* If we can read-modify-write exactly the size of the 1139 containing type (e.g. short or int) then do so. This 1140 is safer for volatile bitfields mapped to hardware 1141 registers. */ 1142 if (changed_len < TYPE_LENGTH (type) 1143 && TYPE_LENGTH (type) <= (int) sizeof (LONGEST) 1144 && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0) 1145 changed_len = TYPE_LENGTH (type); 1146 1147 if (changed_len > (int) sizeof (LONGEST)) 1148 error (_("Can't handle bitfields which don't fit in a %d bit word."), 1149 (int) sizeof (LONGEST) * HOST_CHAR_BIT); 1150 1151 read_memory (changed_addr, buffer, changed_len); 1152 modify_field (type, buffer, value_as_long (fromval), 1153 value_bitpos (toval), value_bitsize (toval)); 1154 dest_buffer = buffer; 1155 } 1156 else 1157 { 1158 changed_addr = value_address (toval); 1159 changed_len = TYPE_LENGTH (type); 1160 dest_buffer = value_contents (fromval); 1161 } 1162 1163 write_memory (changed_addr, dest_buffer, changed_len); 1164 observer_notify_memory_changed (changed_addr, changed_len, 1165 dest_buffer); 1166 } 1167 break; 1168 1169 case lval_register: 1170 { 1171 struct frame_info *frame; 1172 struct gdbarch *gdbarch; 1173 int value_reg; 1174 1175 /* Figure out which frame this is in currently. */ 1176 frame = frame_find_by_id (VALUE_FRAME_ID (toval)); 1177 value_reg = VALUE_REGNUM (toval); 1178 1179 if (!frame) 1180 error (_("Value being assigned to is no longer active.")); 1181 1182 gdbarch = get_frame_arch (frame); 1183 if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval), type)) 1184 { 1185 /* If TOVAL is a special machine register requiring 1186 conversion of program values to a special raw 1187 format. */ 1188 gdbarch_value_to_register (gdbarch, frame, 1189 VALUE_REGNUM (toval), type, 1190 value_contents (fromval)); 1191 } 1192 else 1193 { 1194 if (value_bitsize (toval)) 1195 { 1196 struct value *parent = value_parent (toval); 1197 int offset = value_offset (parent) + value_offset (toval); 1198 int changed_len; 1199 gdb_byte buffer[sizeof (LONGEST)]; 1200 1201 changed_len = (value_bitpos (toval) 1202 + value_bitsize (toval) 1203 + HOST_CHAR_BIT - 1) 1204 / HOST_CHAR_BIT; 1205 1206 if (changed_len > (int) sizeof (LONGEST)) 1207 error (_("Can't handle bitfields which don't fit in a %d bit word."), 1208 (int) sizeof (LONGEST) * HOST_CHAR_BIT); 1209 1210 get_frame_register_bytes (frame, value_reg, offset, 1211 changed_len, buffer); 1212 1213 modify_field (type, buffer, value_as_long (fromval), 1214 value_bitpos (toval), value_bitsize (toval)); 1215 1216 put_frame_register_bytes (frame, value_reg, offset, 1217 changed_len, buffer); 1218 } 1219 else 1220 { 1221 put_frame_register_bytes (frame, value_reg, 1222 value_offset (toval), 1223 TYPE_LENGTH (type), 1224 value_contents (fromval)); 1225 } 1226 } 1227 1228 if (deprecated_register_changed_hook) 1229 deprecated_register_changed_hook (-1); 1230 observer_notify_target_changed (¤t_target); 1231 break; 1232 } 1233 1234 case lval_computed: 1235 { 1236 struct lval_funcs *funcs = value_computed_funcs (toval); 1237 1238 funcs->write (toval, fromval); 1239 } 1240 break; 1241 1242 default: 1243 error (_("Left operand of assignment is not an lvalue.")); 1244 } 1245 1246 /* Assigning to the stack pointer, frame pointer, and other 1247 (architecture and calling convention specific) registers may 1248 cause the frame cache to be out of date. Assigning to memory 1249 also can. We just do this on all assignments to registers or 1250 memory, for simplicity's sake; I doubt the slowdown matters. */ 1251 switch (VALUE_LVAL (toval)) 1252 { 1253 case lval_memory: 1254 case lval_register: 1255 case lval_computed: 1256 1257 reinit_frame_cache (); 1258 1259 /* Having destroyed the frame cache, restore the selected 1260 frame. */ 1261 1262 /* FIXME: cagney/2002-11-02: There has to be a better way of 1263 doing this. Instead of constantly saving/restoring the 1264 frame. Why not create a get_selected_frame() function that, 1265 having saved the selected frame's ID can automatically 1266 re-find the previously selected frame automatically. */ 1267 1268 { 1269 struct frame_info *fi = frame_find_by_id (old_frame); 1270 1271 if (fi != NULL) 1272 select_frame (fi); 1273 } 1274 1275 break; 1276 default: 1277 break; 1278 } 1279 1280 /* If the field does not entirely fill a LONGEST, then zero the sign 1281 bits. If the field is signed, and is negative, then sign 1282 extend. */ 1283 if ((value_bitsize (toval) > 0) 1284 && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST))) 1285 { 1286 LONGEST fieldval = value_as_long (fromval); 1287 LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1; 1288 1289 fieldval &= valmask; 1290 if (!TYPE_UNSIGNED (type) 1291 && (fieldval & (valmask ^ (valmask >> 1)))) 1292 fieldval |= ~valmask; 1293 1294 fromval = value_from_longest (type, fieldval); 1295 } 1296 1297 val = value_copy (toval); 1298 memcpy (value_contents_raw (val), value_contents (fromval), 1299 TYPE_LENGTH (type)); 1300 deprecated_set_value_type (val, type); 1301 val = value_change_enclosing_type (val, 1302 value_enclosing_type (fromval)); 1303 set_value_embedded_offset (val, value_embedded_offset (fromval)); 1304 set_value_pointed_to_offset (val, value_pointed_to_offset (fromval)); 1305 1306 return val; 1307 } 1308 1309 /* Extend a value VAL to COUNT repetitions of its type. */ 1310 1311 struct value * 1312 value_repeat (struct value *arg1, int count) 1313 { 1314 struct value *val; 1315 1316 if (VALUE_LVAL (arg1) != lval_memory) 1317 error (_("Only values in memory can be extended with '@'.")); 1318 if (count < 1) 1319 error (_("Invalid number %d of repetitions."), count); 1320 1321 val = allocate_repeat_value (value_enclosing_type (arg1), count); 1322 1323 read_memory (value_address (arg1), 1324 value_contents_all_raw (val), 1325 TYPE_LENGTH (value_enclosing_type (val))); 1326 VALUE_LVAL (val) = lval_memory; 1327 set_value_address (val, value_address (arg1)); 1328 1329 return val; 1330 } 1331 1332 struct value * 1333 value_of_variable (struct symbol *var, struct block *b) 1334 { 1335 struct value *val; 1336 struct frame_info *frame; 1337 1338 if (!symbol_read_needs_frame (var)) 1339 frame = NULL; 1340 else if (!b) 1341 frame = get_selected_frame (_("No frame selected.")); 1342 else 1343 { 1344 frame = block_innermost_frame (b); 1345 if (!frame) 1346 { 1347 if (BLOCK_FUNCTION (b) && !block_inlined_p (b) 1348 && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b))) 1349 error (_("No frame is currently executing in block %s."), 1350 SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b))); 1351 else 1352 error (_("No frame is currently executing in specified block")); 1353 } 1354 } 1355 1356 val = read_var_value (var, frame); 1357 if (!val) 1358 error (_("Address of symbol \"%s\" is unknown."), SYMBOL_PRINT_NAME (var)); 1359 1360 return val; 1361 } 1362 1363 struct value * 1364 address_of_variable (struct symbol *var, struct block *b) 1365 { 1366 struct type *type = SYMBOL_TYPE (var); 1367 struct value *val; 1368 1369 /* Evaluate it first; if the result is a memory address, we're fine. 1370 Lazy evaluation pays off here. */ 1371 1372 val = value_of_variable (var, b); 1373 1374 if ((VALUE_LVAL (val) == lval_memory && value_lazy (val)) 1375 || TYPE_CODE (type) == TYPE_CODE_FUNC) 1376 { 1377 CORE_ADDR addr = value_address (val); 1378 1379 return value_from_pointer (lookup_pointer_type (type), addr); 1380 } 1381 1382 /* Not a memory address; check what the problem was. */ 1383 switch (VALUE_LVAL (val)) 1384 { 1385 case lval_register: 1386 { 1387 struct frame_info *frame; 1388 const char *regname; 1389 1390 frame = frame_find_by_id (VALUE_FRAME_ID (val)); 1391 gdb_assert (frame); 1392 1393 regname = gdbarch_register_name (get_frame_arch (frame), 1394 VALUE_REGNUM (val)); 1395 gdb_assert (regname && *regname); 1396 1397 error (_("Address requested for identifier " 1398 "\"%s\" which is in register $%s"), 1399 SYMBOL_PRINT_NAME (var), regname); 1400 break; 1401 } 1402 1403 default: 1404 error (_("Can't take address of \"%s\" which isn't an lvalue."), 1405 SYMBOL_PRINT_NAME (var)); 1406 break; 1407 } 1408 1409 return val; 1410 } 1411 1412 /* Return one if VAL does not live in target memory, but should in order 1413 to operate on it. Otherwise return zero. */ 1414 1415 int 1416 value_must_coerce_to_target (struct value *val) 1417 { 1418 struct type *valtype; 1419 1420 /* The only lval kinds which do not live in target memory. */ 1421 if (VALUE_LVAL (val) != not_lval 1422 && VALUE_LVAL (val) != lval_internalvar) 1423 return 0; 1424 1425 valtype = check_typedef (value_type (val)); 1426 1427 switch (TYPE_CODE (valtype)) 1428 { 1429 case TYPE_CODE_ARRAY: 1430 case TYPE_CODE_STRING: 1431 return 1; 1432 default: 1433 return 0; 1434 } 1435 } 1436 1437 /* Make sure that VAL lives in target memory if it's supposed to. For instance, 1438 strings are constructed as character arrays in GDB's storage, and this 1439 function copies them to the target. */ 1440 1441 struct value * 1442 value_coerce_to_target (struct value *val) 1443 { 1444 LONGEST length; 1445 CORE_ADDR addr; 1446 1447 if (!value_must_coerce_to_target (val)) 1448 return val; 1449 1450 length = TYPE_LENGTH (check_typedef (value_type (val))); 1451 addr = allocate_space_in_inferior (length); 1452 write_memory (addr, value_contents (val), length); 1453 return value_at_lazy (value_type (val), addr); 1454 } 1455 1456 /* Given a value which is an array, return a value which is a pointer 1457 to its first element, regardless of whether or not the array has a 1458 nonzero lower bound. 1459 1460 FIXME: A previous comment here indicated that this routine should 1461 be substracting the array's lower bound. It's not clear to me that 1462 this is correct. Given an array subscripting operation, it would 1463 certainly work to do the adjustment here, essentially computing: 1464 1465 (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0]) 1466 1467 However I believe a more appropriate and logical place to account 1468 for the lower bound is to do so in value_subscript, essentially 1469 computing: 1470 1471 (&array[0] + ((index - lowerbound) * sizeof array[0])) 1472 1473 As further evidence consider what would happen with operations 1474 other than array subscripting, where the caller would get back a 1475 value that had an address somewhere before the actual first element 1476 of the array, and the information about the lower bound would be 1477 lost because of the coercion to pointer type. 1478 */ 1479 1480 struct value * 1481 value_coerce_array (struct value *arg1) 1482 { 1483 struct type *type = check_typedef (value_type (arg1)); 1484 1485 /* If the user tries to do something requiring a pointer with an 1486 array that has not yet been pushed to the target, then this would 1487 be a good time to do so. */ 1488 arg1 = value_coerce_to_target (arg1); 1489 1490 if (VALUE_LVAL (arg1) != lval_memory) 1491 error (_("Attempt to take address of value not located in memory.")); 1492 1493 return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)), 1494 value_address (arg1)); 1495 } 1496 1497 /* Given a value which is a function, return a value which is a pointer 1498 to it. */ 1499 1500 struct value * 1501 value_coerce_function (struct value *arg1) 1502 { 1503 struct value *retval; 1504 1505 if (VALUE_LVAL (arg1) != lval_memory) 1506 error (_("Attempt to take address of value not located in memory.")); 1507 1508 retval = value_from_pointer (lookup_pointer_type (value_type (arg1)), 1509 value_address (arg1)); 1510 return retval; 1511 } 1512 1513 /* Return a pointer value for the object for which ARG1 is the 1514 contents. */ 1515 1516 struct value * 1517 value_addr (struct value *arg1) 1518 { 1519 struct value *arg2; 1520 struct type *type = check_typedef (value_type (arg1)); 1521 1522 if (TYPE_CODE (type) == TYPE_CODE_REF) 1523 { 1524 /* Copy the value, but change the type from (T&) to (T*). We 1525 keep the same location information, which is efficient, and 1526 allows &(&X) to get the location containing the reference. */ 1527 arg2 = value_copy (arg1); 1528 deprecated_set_value_type (arg2, 1529 lookup_pointer_type (TYPE_TARGET_TYPE (type))); 1530 return arg2; 1531 } 1532 if (TYPE_CODE (type) == TYPE_CODE_FUNC) 1533 return value_coerce_function (arg1); 1534 1535 /* If this is an array that has not yet been pushed to the target, 1536 then this would be a good time to force it to memory. */ 1537 arg1 = value_coerce_to_target (arg1); 1538 1539 if (VALUE_LVAL (arg1) != lval_memory) 1540 error (_("Attempt to take address of value not located in memory.")); 1541 1542 /* Get target memory address */ 1543 arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)), 1544 (value_address (arg1) 1545 + value_embedded_offset (arg1))); 1546 1547 /* This may be a pointer to a base subobject; so remember the 1548 full derived object's type ... */ 1549 arg2 = value_change_enclosing_type (arg2, lookup_pointer_type (value_enclosing_type (arg1))); 1550 /* ... and also the relative position of the subobject in the full 1551 object. */ 1552 set_value_pointed_to_offset (arg2, value_embedded_offset (arg1)); 1553 return arg2; 1554 } 1555 1556 /* Return a reference value for the object for which ARG1 is the 1557 contents. */ 1558 1559 struct value * 1560 value_ref (struct value *arg1) 1561 { 1562 struct value *arg2; 1563 struct type *type = check_typedef (value_type (arg1)); 1564 1565 if (TYPE_CODE (type) == TYPE_CODE_REF) 1566 return arg1; 1567 1568 arg2 = value_addr (arg1); 1569 deprecated_set_value_type (arg2, lookup_reference_type (type)); 1570 return arg2; 1571 } 1572 1573 /* Given a value of a pointer type, apply the C unary * operator to 1574 it. */ 1575 1576 struct value * 1577 value_ind (struct value *arg1) 1578 { 1579 struct type *base_type; 1580 struct value *arg2; 1581 1582 arg1 = coerce_array (arg1); 1583 1584 base_type = check_typedef (value_type (arg1)); 1585 1586 if (TYPE_CODE (base_type) == TYPE_CODE_PTR) 1587 { 1588 struct type *enc_type; 1589 1590 /* We may be pointing to something embedded in a larger object. 1591 Get the real type of the enclosing object. */ 1592 enc_type = check_typedef (value_enclosing_type (arg1)); 1593 enc_type = TYPE_TARGET_TYPE (enc_type); 1594 1595 if (TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_FUNC 1596 || TYPE_CODE (check_typedef (enc_type)) == TYPE_CODE_METHOD) 1597 /* For functions, go through find_function_addr, which knows 1598 how to handle function descriptors. */ 1599 arg2 = value_at_lazy (enc_type, 1600 find_function_addr (arg1, NULL)); 1601 else 1602 /* Retrieve the enclosing object pointed to */ 1603 arg2 = value_at_lazy (enc_type, 1604 (value_as_address (arg1) 1605 - value_pointed_to_offset (arg1))); 1606 1607 /* Re-adjust type. */ 1608 deprecated_set_value_type (arg2, TYPE_TARGET_TYPE (base_type)); 1609 /* Add embedding info. */ 1610 arg2 = value_change_enclosing_type (arg2, enc_type); 1611 set_value_embedded_offset (arg2, value_pointed_to_offset (arg1)); 1612 1613 /* We may be pointing to an object of some derived type. */ 1614 arg2 = value_full_object (arg2, NULL, 0, 0, 0); 1615 return arg2; 1616 } 1617 1618 error (_("Attempt to take contents of a non-pointer value.")); 1619 return 0; /* For lint -- never reached. */ 1620 } 1621 1622 /* Create a value for an array by allocating space in GDB, copying 1623 copying the data into that space, and then setting up an array 1624 value. 1625 1626 The array bounds are set from LOWBOUND and HIGHBOUND, and the array 1627 is populated from the values passed in ELEMVEC. 1628 1629 The element type of the array is inherited from the type of the 1630 first element, and all elements must have the same size (though we 1631 don't currently enforce any restriction on their types). */ 1632 1633 struct value * 1634 value_array (int lowbound, int highbound, struct value **elemvec) 1635 { 1636 int nelem; 1637 int idx; 1638 unsigned int typelength; 1639 struct value *val; 1640 struct type *arraytype; 1641 1642 /* Validate that the bounds are reasonable and that each of the 1643 elements have the same size. */ 1644 1645 nelem = highbound - lowbound + 1; 1646 if (nelem <= 0) 1647 { 1648 error (_("bad array bounds (%d, %d)"), lowbound, highbound); 1649 } 1650 typelength = TYPE_LENGTH (value_enclosing_type (elemvec[0])); 1651 for (idx = 1; idx < nelem; idx++) 1652 { 1653 if (TYPE_LENGTH (value_enclosing_type (elemvec[idx])) != typelength) 1654 { 1655 error (_("array elements must all be the same size")); 1656 } 1657 } 1658 1659 arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]), 1660 lowbound, highbound); 1661 1662 if (!current_language->c_style_arrays) 1663 { 1664 val = allocate_value (arraytype); 1665 for (idx = 0; idx < nelem; idx++) 1666 { 1667 memcpy (value_contents_all_raw (val) + (idx * typelength), 1668 value_contents_all (elemvec[idx]), 1669 typelength); 1670 } 1671 return val; 1672 } 1673 1674 /* Allocate space to store the array, and then initialize it by 1675 copying in each element. */ 1676 1677 val = allocate_value (arraytype); 1678 for (idx = 0; idx < nelem; idx++) 1679 memcpy (value_contents_writeable (val) + (idx * typelength), 1680 value_contents_all (elemvec[idx]), 1681 typelength); 1682 return val; 1683 } 1684 1685 struct value * 1686 value_cstring (char *ptr, int len, struct type *char_type) 1687 { 1688 struct value *val; 1689 int lowbound = current_language->string_lower_bound; 1690 int highbound = len / TYPE_LENGTH (char_type); 1691 struct type *stringtype 1692 = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1); 1693 1694 val = allocate_value (stringtype); 1695 memcpy (value_contents_raw (val), ptr, len); 1696 return val; 1697 } 1698 1699 /* Create a value for a string constant by allocating space in the 1700 inferior, copying the data into that space, and returning the 1701 address with type TYPE_CODE_STRING. PTR points to the string 1702 constant data; LEN is number of characters. 1703 1704 Note that string types are like array of char types with a lower 1705 bound of zero and an upper bound of LEN - 1. Also note that the 1706 string may contain embedded null bytes. */ 1707 1708 struct value * 1709 value_string (char *ptr, int len, struct type *char_type) 1710 { 1711 struct value *val; 1712 int lowbound = current_language->string_lower_bound; 1713 int highbound = len / TYPE_LENGTH (char_type); 1714 struct type *stringtype 1715 = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1); 1716 1717 val = allocate_value (stringtype); 1718 memcpy (value_contents_raw (val), ptr, len); 1719 return val; 1720 } 1721 1722 struct value * 1723 value_bitstring (char *ptr, int len, struct type *index_type) 1724 { 1725 struct value *val; 1726 struct type *domain_type 1727 = create_range_type (NULL, index_type, 0, len - 1); 1728 struct type *type = create_set_type (NULL, domain_type); 1729 1730 TYPE_CODE (type) = TYPE_CODE_BITSTRING; 1731 val = allocate_value (type); 1732 memcpy (value_contents_raw (val), ptr, TYPE_LENGTH (type)); 1733 return val; 1734 } 1735 1736 /* See if we can pass arguments in T2 to a function which takes 1737 arguments of types T1. T1 is a list of NARGS arguments, and T2 is 1738 a NULL-terminated vector. If some arguments need coercion of some 1739 sort, then the coerced values are written into T2. Return value is 1740 0 if the arguments could be matched, or the position at which they 1741 differ if not. 1742 1743 STATICP is nonzero if the T1 argument list came from a static 1744 member function. T2 will still include the ``this'' pointer, but 1745 it will be skipped. 1746 1747 For non-static member functions, we ignore the first argument, 1748 which is the type of the instance variable. This is because we 1749 want to handle calls with objects from derived classes. This is 1750 not entirely correct: we should actually check to make sure that a 1751 requested operation is type secure, shouldn't we? FIXME. */ 1752 1753 static int 1754 typecmp (int staticp, int varargs, int nargs, 1755 struct field t1[], struct value *t2[]) 1756 { 1757 int i; 1758 1759 if (t2 == 0) 1760 internal_error (__FILE__, __LINE__, 1761 _("typecmp: no argument list")); 1762 1763 /* Skip ``this'' argument if applicable. T2 will always include 1764 THIS. */ 1765 if (staticp) 1766 t2 ++; 1767 1768 for (i = 0; 1769 (i < nargs) && TYPE_CODE (t1[i].type) != TYPE_CODE_VOID; 1770 i++) 1771 { 1772 struct type *tt1, *tt2; 1773 1774 if (!t2[i]) 1775 return i + 1; 1776 1777 tt1 = check_typedef (t1[i].type); 1778 tt2 = check_typedef (value_type (t2[i])); 1779 1780 if (TYPE_CODE (tt1) == TYPE_CODE_REF 1781 /* We should be doing hairy argument matching, as below. */ 1782 && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2))) 1783 { 1784 if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY) 1785 t2[i] = value_coerce_array (t2[i]); 1786 else 1787 t2[i] = value_ref (t2[i]); 1788 continue; 1789 } 1790 1791 /* djb - 20000715 - Until the new type structure is in the 1792 place, and we can attempt things like implicit conversions, 1793 we need to do this so you can take something like a map<const 1794 char *>, and properly access map["hello"], because the 1795 argument to [] will be a reference to a pointer to a char, 1796 and the argument will be a pointer to a char. */ 1797 while (TYPE_CODE(tt1) == TYPE_CODE_REF 1798 || TYPE_CODE (tt1) == TYPE_CODE_PTR) 1799 { 1800 tt1 = check_typedef( TYPE_TARGET_TYPE(tt1) ); 1801 } 1802 while (TYPE_CODE(tt2) == TYPE_CODE_ARRAY 1803 || TYPE_CODE(tt2) == TYPE_CODE_PTR 1804 || TYPE_CODE(tt2) == TYPE_CODE_REF) 1805 { 1806 tt2 = check_typedef (TYPE_TARGET_TYPE(tt2)); 1807 } 1808 if (TYPE_CODE (tt1) == TYPE_CODE (tt2)) 1809 continue; 1810 /* Array to pointer is a `trivial conversion' according to the 1811 ARM. */ 1812 1813 /* We should be doing much hairier argument matching (see 1814 section 13.2 of the ARM), but as a quick kludge, just check 1815 for the same type code. */ 1816 if (TYPE_CODE (t1[i].type) != TYPE_CODE (value_type (t2[i]))) 1817 return i + 1; 1818 } 1819 if (varargs || t2[i] == NULL) 1820 return 0; 1821 return i + 1; 1822 } 1823 1824 /* Helper function used by value_struct_elt to recurse through 1825 baseclasses. Look for a field NAME in ARG1. Adjust the address of 1826 ARG1 by OFFSET bytes, and search in it assuming it has (class) type 1827 TYPE. If found, return value, else return NULL. 1828 1829 If LOOKING_FOR_BASECLASS, then instead of looking for struct 1830 fields, look for a baseclass named NAME. */ 1831 1832 static struct value * 1833 search_struct_field (const char *name, struct value *arg1, int offset, 1834 struct type *type, int looking_for_baseclass) 1835 { 1836 int i; 1837 int nbases; 1838 1839 CHECK_TYPEDEF (type); 1840 nbases = TYPE_N_BASECLASSES (type); 1841 1842 if (!looking_for_baseclass) 1843 for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--) 1844 { 1845 char *t_field_name = TYPE_FIELD_NAME (type, i); 1846 1847 if (t_field_name && (strcmp_iw (t_field_name, name) == 0)) 1848 { 1849 struct value *v; 1850 1851 if (field_is_static (&TYPE_FIELD (type, i))) 1852 { 1853 v = value_static_field (type, i); 1854 if (v == 0) 1855 error (_("field %s is nonexistent or has been optimized out"), 1856 name); 1857 } 1858 else 1859 { 1860 v = value_primitive_field (arg1, offset, i, type); 1861 if (v == 0) 1862 error (_("there is no field named %s"), name); 1863 } 1864 return v; 1865 } 1866 1867 if (t_field_name 1868 && (t_field_name[0] == '\0' 1869 || (TYPE_CODE (type) == TYPE_CODE_UNION 1870 && (strcmp_iw (t_field_name, "else") == 0)))) 1871 { 1872 struct type *field_type = TYPE_FIELD_TYPE (type, i); 1873 1874 if (TYPE_CODE (field_type) == TYPE_CODE_UNION 1875 || TYPE_CODE (field_type) == TYPE_CODE_STRUCT) 1876 { 1877 /* Look for a match through the fields of an anonymous 1878 union, or anonymous struct. C++ provides anonymous 1879 unions. 1880 1881 In the GNU Chill (now deleted from GDB) 1882 implementation of variant record types, each 1883 <alternative field> has an (anonymous) union type, 1884 each member of the union represents a <variant 1885 alternative>. Each <variant alternative> is 1886 represented as a struct, with a member for each 1887 <variant field>. */ 1888 1889 struct value *v; 1890 int new_offset = offset; 1891 1892 /* This is pretty gross. In G++, the offset in an 1893 anonymous union is relative to the beginning of the 1894 enclosing struct. In the GNU Chill (now deleted 1895 from GDB) implementation of variant records, the 1896 bitpos is zero in an anonymous union field, so we 1897 have to add the offset of the union here. */ 1898 if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT 1899 || (TYPE_NFIELDS (field_type) > 0 1900 && TYPE_FIELD_BITPOS (field_type, 0) == 0)) 1901 new_offset += TYPE_FIELD_BITPOS (type, i) / 8; 1902 1903 v = search_struct_field (name, arg1, new_offset, 1904 field_type, 1905 looking_for_baseclass); 1906 if (v) 1907 return v; 1908 } 1909 } 1910 } 1911 1912 for (i = 0; i < nbases; i++) 1913 { 1914 struct value *v; 1915 struct type *basetype = check_typedef (TYPE_BASECLASS (type, i)); 1916 /* If we are looking for baseclasses, this is what we get when 1917 we hit them. But it could happen that the base part's member 1918 name is not yet filled in. */ 1919 int found_baseclass = (looking_for_baseclass 1920 && TYPE_BASECLASS_NAME (type, i) != NULL 1921 && (strcmp_iw (name, 1922 TYPE_BASECLASS_NAME (type, 1923 i)) == 0)); 1924 1925 if (BASETYPE_VIA_VIRTUAL (type, i)) 1926 { 1927 int boffset; 1928 struct value *v2; 1929 1930 boffset = baseclass_offset (type, i, 1931 value_contents (arg1) + offset, 1932 value_address (arg1) 1933 + value_embedded_offset (arg1) 1934 + offset); 1935 if (boffset == -1) 1936 error (_("virtual baseclass botch")); 1937 1938 /* The virtual base class pointer might have been clobbered 1939 by the user program. Make sure that it still points to a 1940 valid memory location. */ 1941 1942 boffset += value_embedded_offset (arg1) + offset; 1943 if (boffset < 0 1944 || boffset >= TYPE_LENGTH (value_enclosing_type (arg1))) 1945 { 1946 CORE_ADDR base_addr; 1947 1948 v2 = allocate_value (basetype); 1949 base_addr = value_address (arg1) + boffset; 1950 if (target_read_memory (base_addr, 1951 value_contents_raw (v2), 1952 TYPE_LENGTH (basetype)) != 0) 1953 error (_("virtual baseclass botch")); 1954 VALUE_LVAL (v2) = lval_memory; 1955 set_value_address (v2, base_addr); 1956 } 1957 else 1958 { 1959 v2 = value_copy (arg1); 1960 deprecated_set_value_type (v2, basetype); 1961 set_value_embedded_offset (v2, boffset); 1962 } 1963 1964 if (found_baseclass) 1965 return v2; 1966 v = search_struct_field (name, v2, 0, 1967 TYPE_BASECLASS (type, i), 1968 looking_for_baseclass); 1969 } 1970 else if (found_baseclass) 1971 v = value_primitive_field (arg1, offset, i, type); 1972 else 1973 v = search_struct_field (name, arg1, 1974 offset + TYPE_BASECLASS_BITPOS (type, 1975 i) / 8, 1976 basetype, looking_for_baseclass); 1977 if (v) 1978 return v; 1979 } 1980 return NULL; 1981 } 1982 1983 /* Helper function used by value_struct_elt to recurse through 1984 baseclasses. Look for a field NAME in ARG1. Adjust the address of 1985 ARG1 by OFFSET bytes, and search in it assuming it has (class) type 1986 TYPE. 1987 1988 If found, return value, else if name matched and args not return 1989 (value) -1, else return NULL. */ 1990 1991 static struct value * 1992 search_struct_method (const char *name, struct value **arg1p, 1993 struct value **args, int offset, 1994 int *static_memfuncp, struct type *type) 1995 { 1996 int i; 1997 struct value *v; 1998 int name_matched = 0; 1999 char dem_opname[64]; 2000 2001 CHECK_TYPEDEF (type); 2002 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--) 2003 { 2004 char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i); 2005 2006 /* FIXME! May need to check for ARM demangling here */ 2007 if (strncmp (t_field_name, "__", 2) == 0 || 2008 strncmp (t_field_name, "op", 2) == 0 || 2009 strncmp (t_field_name, "type", 4) == 0) 2010 { 2011 if (cplus_demangle_opname (t_field_name, dem_opname, DMGL_ANSI)) 2012 t_field_name = dem_opname; 2013 else if (cplus_demangle_opname (t_field_name, dem_opname, 0)) 2014 t_field_name = dem_opname; 2015 } 2016 if (t_field_name && (strcmp_iw (t_field_name, name) == 0)) 2017 { 2018 int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1; 2019 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i); 2020 2021 name_matched = 1; 2022 check_stub_method_group (type, i); 2023 if (j > 0 && args == 0) 2024 error (_("cannot resolve overloaded method `%s': no arguments supplied"), name); 2025 else if (j == 0 && args == 0) 2026 { 2027 v = value_fn_field (arg1p, f, j, type, offset); 2028 if (v != NULL) 2029 return v; 2030 } 2031 else 2032 while (j >= 0) 2033 { 2034 if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j), 2035 TYPE_VARARGS (TYPE_FN_FIELD_TYPE (f, j)), 2036 TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (f, j)), 2037 TYPE_FN_FIELD_ARGS (f, j), args)) 2038 { 2039 if (TYPE_FN_FIELD_VIRTUAL_P (f, j)) 2040 return value_virtual_fn_field (arg1p, f, j, 2041 type, offset); 2042 if (TYPE_FN_FIELD_STATIC_P (f, j) 2043 && static_memfuncp) 2044 *static_memfuncp = 1; 2045 v = value_fn_field (arg1p, f, j, type, offset); 2046 if (v != NULL) 2047 return v; 2048 } 2049 j--; 2050 } 2051 } 2052 } 2053 2054 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) 2055 { 2056 int base_offset; 2057 2058 if (BASETYPE_VIA_VIRTUAL (type, i)) 2059 { 2060 struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i)); 2061 const gdb_byte *base_valaddr; 2062 2063 /* The virtual base class pointer might have been 2064 clobbered by the user program. Make sure that it 2065 still points to a valid memory location. */ 2066 2067 if (offset < 0 || offset >= TYPE_LENGTH (type)) 2068 { 2069 gdb_byte *tmp = alloca (TYPE_LENGTH (baseclass)); 2070 2071 if (target_read_memory (value_address (*arg1p) + offset, 2072 tmp, TYPE_LENGTH (baseclass)) != 0) 2073 error (_("virtual baseclass botch")); 2074 base_valaddr = tmp; 2075 } 2076 else 2077 base_valaddr = value_contents (*arg1p) + offset; 2078 2079 base_offset = baseclass_offset (type, i, base_valaddr, 2080 value_address (*arg1p) + offset); 2081 if (base_offset == -1) 2082 error (_("virtual baseclass botch")); 2083 } 2084 else 2085 { 2086 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8; 2087 } 2088 v = search_struct_method (name, arg1p, args, base_offset + offset, 2089 static_memfuncp, TYPE_BASECLASS (type, i)); 2090 if (v == (struct value *) - 1) 2091 { 2092 name_matched = 1; 2093 } 2094 else if (v) 2095 { 2096 /* FIXME-bothner: Why is this commented out? Why is it here? */ 2097 /* *arg1p = arg1_tmp; */ 2098 return v; 2099 } 2100 } 2101 if (name_matched) 2102 return (struct value *) - 1; 2103 else 2104 return NULL; 2105 } 2106 2107 /* Given *ARGP, a value of type (pointer to a)* structure/union, 2108 extract the component named NAME from the ultimate target 2109 structure/union and return it as a value with its appropriate type. 2110 ERR is used in the error message if *ARGP's type is wrong. 2111 2112 C++: ARGS is a list of argument types to aid in the selection of 2113 an appropriate method. Also, handle derived types. 2114 2115 STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location 2116 where the truthvalue of whether the function that was resolved was 2117 a static member function or not is stored. 2118 2119 ERR is an error message to be printed in case the field is not 2120 found. */ 2121 2122 struct value * 2123 value_struct_elt (struct value **argp, struct value **args, 2124 const char *name, int *static_memfuncp, const char *err) 2125 { 2126 struct type *t; 2127 struct value *v; 2128 2129 *argp = coerce_array (*argp); 2130 2131 t = check_typedef (value_type (*argp)); 2132 2133 /* Follow pointers until we get to a non-pointer. */ 2134 2135 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF) 2136 { 2137 *argp = value_ind (*argp); 2138 /* Don't coerce fn pointer to fn and then back again! */ 2139 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC) 2140 *argp = coerce_array (*argp); 2141 t = check_typedef (value_type (*argp)); 2142 } 2143 2144 if (TYPE_CODE (t) != TYPE_CODE_STRUCT 2145 && TYPE_CODE (t) != TYPE_CODE_UNION) 2146 error (_("Attempt to extract a component of a value that is not a %s."), err); 2147 2148 /* Assume it's not, unless we see that it is. */ 2149 if (static_memfuncp) 2150 *static_memfuncp = 0; 2151 2152 if (!args) 2153 { 2154 /* if there are no arguments ...do this... */ 2155 2156 /* Try as a field first, because if we succeed, there is less 2157 work to be done. */ 2158 v = search_struct_field (name, *argp, 0, t, 0); 2159 if (v) 2160 return v; 2161 2162 /* C++: If it was not found as a data field, then try to 2163 return it as a pointer to a method. */ 2164 v = search_struct_method (name, argp, args, 0, 2165 static_memfuncp, t); 2166 2167 if (v == (struct value *) - 1) 2168 error (_("Cannot take address of method %s."), name); 2169 else if (v == 0) 2170 { 2171 if (TYPE_NFN_FIELDS (t)) 2172 error (_("There is no member or method named %s."), name); 2173 else 2174 error (_("There is no member named %s."), name); 2175 } 2176 return v; 2177 } 2178 2179 v = search_struct_method (name, argp, args, 0, 2180 static_memfuncp, t); 2181 2182 if (v == (struct value *) - 1) 2183 { 2184 error (_("One of the arguments you tried to pass to %s could not be converted to what the function wants."), name); 2185 } 2186 else if (v == 0) 2187 { 2188 /* See if user tried to invoke data as function. If so, hand it 2189 back. If it's not callable (i.e., a pointer to function), 2190 gdb should give an error. */ 2191 v = search_struct_field (name, *argp, 0, t, 0); 2192 /* If we found an ordinary field, then it is not a method call. 2193 So, treat it as if it were a static member function. */ 2194 if (v && static_memfuncp) 2195 *static_memfuncp = 1; 2196 } 2197 2198 if (!v) 2199 error (_("Structure has no component named %s."), name); 2200 return v; 2201 } 2202 2203 /* Search through the methods of an object (and its bases) to find a 2204 specified method. Return the pointer to the fn_field list of 2205 overloaded instances. 2206 2207 Helper function for value_find_oload_list. 2208 ARGP is a pointer to a pointer to a value (the object). 2209 METHOD is a string containing the method name. 2210 OFFSET is the offset within the value. 2211 TYPE is the assumed type of the object. 2212 NUM_FNS is the number of overloaded instances. 2213 BASETYPE is set to the actual type of the subobject where the 2214 method is found. 2215 BOFFSET is the offset of the base subobject where the method is found. 2216 */ 2217 2218 static struct fn_field * 2219 find_method_list (struct value **argp, const char *method, 2220 int offset, struct type *type, int *num_fns, 2221 struct type **basetype, int *boffset) 2222 { 2223 int i; 2224 struct fn_field *f; 2225 CHECK_TYPEDEF (type); 2226 2227 *num_fns = 0; 2228 2229 /* First check in object itself. */ 2230 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--) 2231 { 2232 /* pai: FIXME What about operators and type conversions? */ 2233 char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i); 2234 2235 if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0)) 2236 { 2237 int len = TYPE_FN_FIELDLIST_LENGTH (type, i); 2238 struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i); 2239 2240 *num_fns = len; 2241 *basetype = type; 2242 *boffset = offset; 2243 2244 /* Resolve any stub methods. */ 2245 check_stub_method_group (type, i); 2246 2247 return f; 2248 } 2249 } 2250 2251 /* Not found in object, check in base subobjects. */ 2252 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) 2253 { 2254 int base_offset; 2255 2256 if (BASETYPE_VIA_VIRTUAL (type, i)) 2257 { 2258 base_offset = value_offset (*argp) + offset; 2259 base_offset = baseclass_offset (type, i, 2260 value_contents (*argp) + base_offset, 2261 value_address (*argp) + base_offset); 2262 if (base_offset == -1) 2263 error (_("virtual baseclass botch")); 2264 } 2265 else /* Non-virtual base, simply use bit position from debug 2266 info. */ 2267 { 2268 base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8; 2269 } 2270 f = find_method_list (argp, method, base_offset + offset, 2271 TYPE_BASECLASS (type, i), num_fns, 2272 basetype, boffset); 2273 if (f) 2274 return f; 2275 } 2276 return NULL; 2277 } 2278 2279 /* Return the list of overloaded methods of a specified name. 2280 2281 ARGP is a pointer to a pointer to a value (the object). 2282 METHOD is the method name. 2283 OFFSET is the offset within the value contents. 2284 NUM_FNS is the number of overloaded instances. 2285 BASETYPE is set to the type of the base subobject that defines the 2286 method. 2287 BOFFSET is the offset of the base subobject which defines the method. 2288 */ 2289 2290 struct fn_field * 2291 value_find_oload_method_list (struct value **argp, const char *method, 2292 int offset, int *num_fns, 2293 struct type **basetype, int *boffset) 2294 { 2295 struct type *t; 2296 2297 t = check_typedef (value_type (*argp)); 2298 2299 /* Code snarfed from value_struct_elt. */ 2300 while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF) 2301 { 2302 *argp = value_ind (*argp); 2303 /* Don't coerce fn pointer to fn and then back again! */ 2304 if (TYPE_CODE (value_type (*argp)) != TYPE_CODE_FUNC) 2305 *argp = coerce_array (*argp); 2306 t = check_typedef (value_type (*argp)); 2307 } 2308 2309 if (TYPE_CODE (t) != TYPE_CODE_STRUCT 2310 && TYPE_CODE (t) != TYPE_CODE_UNION) 2311 error (_("Attempt to extract a component of a value that is not a struct or union")); 2312 2313 return find_method_list (argp, method, 0, t, num_fns, 2314 basetype, boffset); 2315 } 2316 2317 /* Given an array of argument types (ARGTYPES) (which includes an 2318 entry for "this" in the case of C++ methods), the number of 2319 arguments NARGS, the NAME of a function whether it's a method or 2320 not (METHOD), and the degree of laxness (LAX) in conforming to 2321 overload resolution rules in ANSI C++, find the best function that 2322 matches on the argument types according to the overload resolution 2323 rules. 2324 2325 METHOD can be one of three values: 2326 NON_METHOD for non-member functions. 2327 METHOD: for member functions. 2328 BOTH: used for overload resolution of operators where the 2329 candidates are expected to be either member or non member 2330 functions. In this case the first argument ARGTYPES 2331 (representing 'this') is expected to be a reference to the 2332 target object, and will be dereferenced when attempting the 2333 non-member search. 2334 2335 In the case of class methods, the parameter OBJ is an object value 2336 in which to search for overloaded methods. 2337 2338 In the case of non-method functions, the parameter FSYM is a symbol 2339 corresponding to one of the overloaded functions. 2340 2341 Return value is an integer: 0 -> good match, 10 -> debugger applied 2342 non-standard coercions, 100 -> incompatible. 2343 2344 If a method is being searched for, VALP will hold the value. 2345 If a non-method is being searched for, SYMP will hold the symbol 2346 for it. 2347 2348 If a method is being searched for, and it is a static method, 2349 then STATICP will point to a non-zero value. 2350 2351 If NO_ADL argument dependent lookup is disabled. This is used to prevent 2352 ADL overload candidates when performing overload resolution for a fully 2353 qualified name. 2354 2355 Note: This function does *not* check the value of 2356 overload_resolution. Caller must check it to see whether overload 2357 resolution is permitted. 2358 */ 2359 2360 int 2361 find_overload_match (struct type **arg_types, int nargs, 2362 const char *name, enum oload_search_type method, 2363 int lax, struct value **objp, struct symbol *fsym, 2364 struct value **valp, struct symbol **symp, 2365 int *staticp, const int no_adl) 2366 { 2367 struct value *obj = (objp ? *objp : NULL); 2368 /* Index of best overloaded function. */ 2369 int func_oload_champ = -1; 2370 int method_oload_champ = -1; 2371 2372 /* The measure for the current best match. */ 2373 struct badness_vector *method_badness = NULL; 2374 struct badness_vector *func_badness = NULL; 2375 2376 struct value *temp = obj; 2377 /* For methods, the list of overloaded methods. */ 2378 struct fn_field *fns_ptr = NULL; 2379 /* For non-methods, the list of overloaded function symbols. */ 2380 struct symbol **oload_syms = NULL; 2381 /* Number of overloaded instances being considered. */ 2382 int num_fns = 0; 2383 struct type *basetype = NULL; 2384 int boffset; 2385 2386 struct cleanup *all_cleanups = make_cleanup (null_cleanup, NULL); 2387 2388 const char *obj_type_name = NULL; 2389 const char *func_name = NULL; 2390 enum oload_classification match_quality; 2391 enum oload_classification method_match_quality = INCOMPATIBLE; 2392 enum oload_classification func_match_quality = INCOMPATIBLE; 2393 2394 /* Get the list of overloaded methods or functions. */ 2395 if (method == METHOD || method == BOTH) 2396 { 2397 gdb_assert (obj); 2398 2399 /* OBJ may be a pointer value rather than the object itself. */ 2400 obj = coerce_ref (obj); 2401 while (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_PTR) 2402 obj = coerce_ref (value_ind (obj)); 2403 obj_type_name = TYPE_NAME (value_type (obj)); 2404 2405 /* First check whether this is a data member, e.g. a pointer to 2406 a function. */ 2407 if (TYPE_CODE (check_typedef (value_type (obj))) == TYPE_CODE_STRUCT) 2408 { 2409 *valp = search_struct_field (name, obj, 0, 2410 check_typedef (value_type (obj)), 0); 2411 if (*valp) 2412 { 2413 *staticp = 1; 2414 return 0; 2415 } 2416 } 2417 2418 /* Retrieve the list of methods with the name NAME. */ 2419 fns_ptr = value_find_oload_method_list (&temp, name, 2420 0, &num_fns, 2421 &basetype, &boffset); 2422 /* If this is a method only search, and no methods were found 2423 the search has faild. */ 2424 if (method == METHOD && (!fns_ptr || !num_fns)) 2425 error (_("Couldn't find method %s%s%s"), 2426 obj_type_name, 2427 (obj_type_name && *obj_type_name) ? "::" : "", 2428 name); 2429 /* If we are dealing with stub method types, they should have 2430 been resolved by find_method_list via 2431 value_find_oload_method_list above. */ 2432 if (fns_ptr) 2433 { 2434 gdb_assert (TYPE_DOMAIN_TYPE (fns_ptr[0].type) != NULL); 2435 method_oload_champ = find_oload_champ (arg_types, nargs, method, 2436 num_fns, fns_ptr, 2437 oload_syms, &method_badness); 2438 2439 method_match_quality = 2440 classify_oload_match (method_badness, nargs, 2441 oload_method_static (method, fns_ptr, 2442 method_oload_champ)); 2443 2444 make_cleanup (xfree, method_badness); 2445 } 2446 2447 } 2448 2449 if (method == NON_METHOD || method == BOTH) 2450 { 2451 const char *qualified_name = NULL; 2452 2453 /* If the the overload match is being search for both 2454 as a method and non member function, the first argument 2455 must now be dereferenced. */ 2456 if (method == BOTH) 2457 arg_types[0] = TYPE_TARGET_TYPE (arg_types[0]); 2458 2459 if (fsym) 2460 { 2461 qualified_name = SYMBOL_NATURAL_NAME (fsym); 2462 2463 /* If we have a function with a C++ name, try to extract just 2464 the function part. Do not try this for non-functions (e.g. 2465 function pointers). */ 2466 if (qualified_name 2467 && TYPE_CODE (check_typedef (SYMBOL_TYPE (fsym))) == TYPE_CODE_FUNC) 2468 { 2469 char *temp; 2470 2471 temp = cp_func_name (qualified_name); 2472 2473 /* If cp_func_name did not remove anything, the name of the 2474 symbol did not include scope or argument types - it was 2475 probably a C-style function. */ 2476 if (temp) 2477 { 2478 make_cleanup (xfree, temp); 2479 if (strcmp (temp, qualified_name) == 0) 2480 func_name = NULL; 2481 else 2482 func_name = temp; 2483 } 2484 } 2485 } 2486 else 2487 { 2488 func_name = name; 2489 qualified_name = name; 2490 } 2491 2492 /* If there was no C++ name, this must be a C-style function or 2493 not a function at all. Just return the same symbol. Do the 2494 same if cp_func_name fails for some reason. */ 2495 if (func_name == NULL) 2496 { 2497 *symp = fsym; 2498 return 0; 2499 } 2500 2501 func_oload_champ = find_oload_champ_namespace (arg_types, nargs, 2502 func_name, 2503 qualified_name, 2504 &oload_syms, 2505 &func_badness, 2506 no_adl); 2507 2508 if (func_oload_champ >= 0) 2509 func_match_quality = classify_oload_match (func_badness, nargs, 0); 2510 2511 make_cleanup (xfree, oload_syms); 2512 make_cleanup (xfree, func_badness); 2513 } 2514 2515 /* Did we find a match ? */ 2516 if (method_oload_champ == -1 && func_oload_champ == -1) 2517 error (_("No symbol \"%s\" in current context."), name); 2518 2519 /* If we have found both a method match and a function 2520 match, find out which one is better, and calculate match 2521 quality. */ 2522 if (method_oload_champ >= 0 && func_oload_champ >= 0) 2523 { 2524 switch (compare_badness (func_badness, method_badness)) 2525 { 2526 case 0: /* Top two contenders are equally good. */ 2527 /* FIXME: GDB does not support the general ambiguous 2528 case. All candidates should be collected and presented 2529 the the user. */ 2530 error (_("Ambiguous overload resolution")); 2531 break; 2532 case 1: /* Incomparable top contenders. */ 2533 /* This is an error incompatible candidates 2534 should not have been proposed. */ 2535 error (_("Internal error: incompatible overload candidates proposed")); 2536 break; 2537 case 2: /* Function champion. */ 2538 method_oload_champ = -1; 2539 match_quality = func_match_quality; 2540 break; 2541 case 3: /* Method champion. */ 2542 func_oload_champ = -1; 2543 match_quality = method_match_quality; 2544 break; 2545 default: 2546 error (_("Internal error: unexpected overload comparison result")); 2547 break; 2548 } 2549 } 2550 else 2551 { 2552 /* We have either a method match or a function match. */ 2553 if (method_oload_champ >= 0) 2554 match_quality = method_match_quality; 2555 else 2556 match_quality = func_match_quality; 2557 } 2558 2559 if (match_quality == INCOMPATIBLE) 2560 { 2561 if (method == METHOD) 2562 error (_("Cannot resolve method %s%s%s to any overloaded instance"), 2563 obj_type_name, 2564 (obj_type_name && *obj_type_name) ? "::" : "", 2565 name); 2566 else 2567 error (_("Cannot resolve function %s to any overloaded instance"), 2568 func_name); 2569 } 2570 else if (match_quality == NON_STANDARD) 2571 { 2572 if (method == METHOD) 2573 warning (_("Using non-standard conversion to match method %s%s%s to supplied arguments"), 2574 obj_type_name, 2575 (obj_type_name && *obj_type_name) ? "::" : "", 2576 name); 2577 else 2578 warning (_("Using non-standard conversion to match function %s to supplied arguments"), 2579 func_name); 2580 } 2581 2582 if (staticp != NULL) 2583 *staticp = oload_method_static (method, fns_ptr, method_oload_champ); 2584 2585 if (method_oload_champ >= 0) 2586 { 2587 if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, method_oload_champ)) 2588 *valp = value_virtual_fn_field (&temp, fns_ptr, method_oload_champ, 2589 basetype, boffset); 2590 else 2591 *valp = value_fn_field (&temp, fns_ptr, method_oload_champ, 2592 basetype, boffset); 2593 } 2594 else 2595 *symp = oload_syms[func_oload_champ]; 2596 2597 if (objp) 2598 { 2599 struct type *temp_type = check_typedef (value_type (temp)); 2600 struct type *obj_type = check_typedef (value_type (*objp)); 2601 2602 if (TYPE_CODE (temp_type) != TYPE_CODE_PTR 2603 && (TYPE_CODE (obj_type) == TYPE_CODE_PTR 2604 || TYPE_CODE (obj_type) == TYPE_CODE_REF)) 2605 { 2606 temp = value_addr (temp); 2607 } 2608 *objp = temp; 2609 } 2610 2611 do_cleanups (all_cleanups); 2612 2613 switch (match_quality) 2614 { 2615 case INCOMPATIBLE: 2616 return 100; 2617 case NON_STANDARD: 2618 return 10; 2619 default: /* STANDARD */ 2620 return 0; 2621 } 2622 } 2623 2624 /* Find the best overload match, searching for FUNC_NAME in namespaces 2625 contained in QUALIFIED_NAME until it either finds a good match or 2626 runs out of namespaces. It stores the overloaded functions in 2627 *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. The 2628 calling function is responsible for freeing *OLOAD_SYMS and 2629 *OLOAD_CHAMP_BV. If NO_ADL, argument dependent lookup is not 2630 performned. */ 2631 2632 static int 2633 find_oload_champ_namespace (struct type **arg_types, int nargs, 2634 const char *func_name, 2635 const char *qualified_name, 2636 struct symbol ***oload_syms, 2637 struct badness_vector **oload_champ_bv, 2638 const int no_adl) 2639 { 2640 int oload_champ; 2641 2642 find_oload_champ_namespace_loop (arg_types, nargs, 2643 func_name, 2644 qualified_name, 0, 2645 oload_syms, oload_champ_bv, 2646 &oload_champ, 2647 no_adl); 2648 2649 return oload_champ; 2650 } 2651 2652 /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is 2653 how deep we've looked for namespaces, and the champ is stored in 2654 OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0 2655 if it isn't. Other arguments are the same as in 2656 find_oload_champ_namespace 2657 2658 It is the caller's responsibility to free *OLOAD_SYMS and 2659 *OLOAD_CHAMP_BV. */ 2660 2661 static int 2662 find_oload_champ_namespace_loop (struct type **arg_types, int nargs, 2663 const char *func_name, 2664 const char *qualified_name, 2665 int namespace_len, 2666 struct symbol ***oload_syms, 2667 struct badness_vector **oload_champ_bv, 2668 int *oload_champ, 2669 const int no_adl) 2670 { 2671 int next_namespace_len = namespace_len; 2672 int searched_deeper = 0; 2673 int num_fns = 0; 2674 struct cleanup *old_cleanups; 2675 int new_oload_champ; 2676 struct symbol **new_oload_syms; 2677 struct badness_vector *new_oload_champ_bv; 2678 char *new_namespace; 2679 2680 if (next_namespace_len != 0) 2681 { 2682 gdb_assert (qualified_name[next_namespace_len] == ':'); 2683 next_namespace_len += 2; 2684 } 2685 next_namespace_len += 2686 cp_find_first_component (qualified_name + next_namespace_len); 2687 2688 /* Initialize these to values that can safely be xfree'd. */ 2689 *oload_syms = NULL; 2690 *oload_champ_bv = NULL; 2691 2692 /* First, see if we have a deeper namespace we can search in. 2693 If we get a good match there, use it. */ 2694 2695 if (qualified_name[next_namespace_len] == ':') 2696 { 2697 searched_deeper = 1; 2698 2699 if (find_oload_champ_namespace_loop (arg_types, nargs, 2700 func_name, qualified_name, 2701 next_namespace_len, 2702 oload_syms, oload_champ_bv, 2703 oload_champ, no_adl)) 2704 { 2705 return 1; 2706 } 2707 }; 2708 2709 /* If we reach here, either we're in the deepest namespace or we 2710 didn't find a good match in a deeper namespace. But, in the 2711 latter case, we still have a bad match in a deeper namespace; 2712 note that we might not find any match at all in the current 2713 namespace. (There's always a match in the deepest namespace, 2714 because this overload mechanism only gets called if there's a 2715 function symbol to start off with.) */ 2716 2717 old_cleanups = make_cleanup (xfree, *oload_syms); 2718 old_cleanups = make_cleanup (xfree, *oload_champ_bv); 2719 new_namespace = alloca (namespace_len + 1); 2720 strncpy (new_namespace, qualified_name, namespace_len); 2721 new_namespace[namespace_len] = '\0'; 2722 new_oload_syms = make_symbol_overload_list (func_name, 2723 new_namespace); 2724 2725 /* If we have reached the deepest level perform argument 2726 determined lookup. */ 2727 if (!searched_deeper && !no_adl) 2728 make_symbol_overload_list_adl (arg_types, nargs, func_name); 2729 2730 while (new_oload_syms[num_fns]) 2731 ++num_fns; 2732 2733 new_oload_champ = find_oload_champ (arg_types, nargs, 0, num_fns, 2734 NULL, new_oload_syms, 2735 &new_oload_champ_bv); 2736 2737 /* Case 1: We found a good match. Free earlier matches (if any), 2738 and return it. Case 2: We didn't find a good match, but we're 2739 not the deepest function. Then go with the bad match that the 2740 deeper function found. Case 3: We found a bad match, and we're 2741 the deepest function. Then return what we found, even though 2742 it's a bad match. */ 2743 2744 if (new_oload_champ != -1 2745 && classify_oload_match (new_oload_champ_bv, nargs, 0) == STANDARD) 2746 { 2747 *oload_syms = new_oload_syms; 2748 *oload_champ = new_oload_champ; 2749 *oload_champ_bv = new_oload_champ_bv; 2750 do_cleanups (old_cleanups); 2751 return 1; 2752 } 2753 else if (searched_deeper) 2754 { 2755 xfree (new_oload_syms); 2756 xfree (new_oload_champ_bv); 2757 discard_cleanups (old_cleanups); 2758 return 0; 2759 } 2760 else 2761 { 2762 *oload_syms = new_oload_syms; 2763 *oload_champ = new_oload_champ; 2764 *oload_champ_bv = new_oload_champ_bv; 2765 discard_cleanups (old_cleanups); 2766 return 0; 2767 } 2768 } 2769 2770 /* Look for a function to take NARGS args of types ARG_TYPES. Find 2771 the best match from among the overloaded methods or functions 2772 (depending on METHOD) given by FNS_PTR or OLOAD_SYMS, respectively. 2773 The number of methods/functions in the list is given by NUM_FNS. 2774 Return the index of the best match; store an indication of the 2775 quality of the match in OLOAD_CHAMP_BV. 2776 2777 It is the caller's responsibility to free *OLOAD_CHAMP_BV. */ 2778 2779 static int 2780 find_oload_champ (struct type **arg_types, int nargs, int method, 2781 int num_fns, struct fn_field *fns_ptr, 2782 struct symbol **oload_syms, 2783 struct badness_vector **oload_champ_bv) 2784 { 2785 int ix; 2786 /* A measure of how good an overloaded instance is. */ 2787 struct badness_vector *bv; 2788 /* Index of best overloaded function. */ 2789 int oload_champ = -1; 2790 /* Current ambiguity state for overload resolution. */ 2791 int oload_ambiguous = 0; 2792 /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */ 2793 2794 *oload_champ_bv = NULL; 2795 2796 /* Consider each candidate in turn. */ 2797 for (ix = 0; ix < num_fns; ix++) 2798 { 2799 int jj; 2800 int static_offset = oload_method_static (method, fns_ptr, ix); 2801 int nparms; 2802 struct type **parm_types; 2803 2804 if (method) 2805 { 2806 nparms = TYPE_NFIELDS (TYPE_FN_FIELD_TYPE (fns_ptr, ix)); 2807 } 2808 else 2809 { 2810 /* If it's not a method, this is the proper place. */ 2811 nparms = TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix])); 2812 } 2813 2814 /* Prepare array of parameter types. */ 2815 parm_types = (struct type **) 2816 xmalloc (nparms * (sizeof (struct type *))); 2817 for (jj = 0; jj < nparms; jj++) 2818 parm_types[jj] = (method 2819 ? (TYPE_FN_FIELD_ARGS (fns_ptr, ix)[jj].type) 2820 : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), 2821 jj)); 2822 2823 /* Compare parameter types to supplied argument types. Skip 2824 THIS for static methods. */ 2825 bv = rank_function (parm_types, nparms, 2826 arg_types + static_offset, 2827 nargs - static_offset); 2828 2829 if (!*oload_champ_bv) 2830 { 2831 *oload_champ_bv = bv; 2832 oload_champ = 0; 2833 } 2834 else /* See whether current candidate is better or worse than 2835 previous best. */ 2836 switch (compare_badness (bv, *oload_champ_bv)) 2837 { 2838 case 0: /* Top two contenders are equally good. */ 2839 oload_ambiguous = 1; 2840 break; 2841 case 1: /* Incomparable top contenders. */ 2842 oload_ambiguous = 2; 2843 break; 2844 case 2: /* New champion, record details. */ 2845 *oload_champ_bv = bv; 2846 oload_ambiguous = 0; 2847 oload_champ = ix; 2848 break; 2849 case 3: 2850 default: 2851 break; 2852 } 2853 xfree (parm_types); 2854 if (overload_debug) 2855 { 2856 if (method) 2857 fprintf_filtered (gdb_stderr, 2858 "Overloaded method instance %s, # of parms %d\n", 2859 fns_ptr[ix].physname, nparms); 2860 else 2861 fprintf_filtered (gdb_stderr, 2862 "Overloaded function instance %s # of parms %d\n", 2863 SYMBOL_DEMANGLED_NAME (oload_syms[ix]), 2864 nparms); 2865 for (jj = 0; jj < nargs - static_offset; jj++) 2866 fprintf_filtered (gdb_stderr, 2867 "...Badness @ %d : %d\n", 2868 jj, bv->rank[jj]); 2869 fprintf_filtered (gdb_stderr, 2870 "Overload resolution champion is %d, ambiguous? %d\n", 2871 oload_champ, oload_ambiguous); 2872 } 2873 } 2874 2875 return oload_champ; 2876 } 2877 2878 /* Return 1 if we're looking at a static method, 0 if we're looking at 2879 a non-static method or a function that isn't a method. */ 2880 2881 static int 2882 oload_method_static (int method, struct fn_field *fns_ptr, int index) 2883 { 2884 if (method && fns_ptr && index >= 0 2885 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index)) 2886 return 1; 2887 else 2888 return 0; 2889 } 2890 2891 /* Check how good an overload match OLOAD_CHAMP_BV represents. */ 2892 2893 static enum oload_classification 2894 classify_oload_match (struct badness_vector *oload_champ_bv, 2895 int nargs, 2896 int static_offset) 2897 { 2898 int ix; 2899 2900 for (ix = 1; ix <= nargs - static_offset; ix++) 2901 { 2902 if (oload_champ_bv->rank[ix] >= 100) 2903 return INCOMPATIBLE; /* Truly mismatched types. */ 2904 else if (oload_champ_bv->rank[ix] >= 10) 2905 return NON_STANDARD; /* Non-standard type conversions 2906 needed. */ 2907 } 2908 2909 return STANDARD; /* Only standard conversions needed. */ 2910 } 2911 2912 /* C++: return 1 is NAME is a legitimate name for the destructor of 2913 type TYPE. If TYPE does not have a destructor, or if NAME is 2914 inappropriate for TYPE, an error is signaled. */ 2915 int 2916 destructor_name_p (const char *name, const struct type *type) 2917 { 2918 if (name[0] == '~') 2919 { 2920 char *dname = type_name_no_tag (type); 2921 char *cp = strchr (dname, '<'); 2922 unsigned int len; 2923 2924 /* Do not compare the template part for template classes. */ 2925 if (cp == NULL) 2926 len = strlen (dname); 2927 else 2928 len = cp - dname; 2929 if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0) 2930 error (_("name of destructor must equal name of class")); 2931 else 2932 return 1; 2933 } 2934 return 0; 2935 } 2936 2937 /* Given TYPE, a structure/union, 2938 return 1 if the component named NAME from the ultimate target 2939 structure/union is defined, otherwise, return 0. */ 2940 2941 int 2942 check_field (struct type *type, const char *name) 2943 { 2944 int i; 2945 2946 /* The type may be a stub. */ 2947 CHECK_TYPEDEF (type); 2948 2949 for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--) 2950 { 2951 char *t_field_name = TYPE_FIELD_NAME (type, i); 2952 2953 if (t_field_name && (strcmp_iw (t_field_name, name) == 0)) 2954 return 1; 2955 } 2956 2957 /* C++: If it was not found as a data field, then try to return it 2958 as a pointer to a method. */ 2959 2960 for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i) 2961 { 2962 if (strcmp_iw (TYPE_FN_FIELDLIST_NAME (type, i), name) == 0) 2963 return 1; 2964 } 2965 2966 for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) 2967 if (check_field (TYPE_BASECLASS (type, i), name)) 2968 return 1; 2969 2970 return 0; 2971 } 2972 2973 /* C++: Given an aggregate type CURTYPE, and a member name NAME, 2974 return the appropriate member (or the address of the member, if 2975 WANT_ADDRESS). This function is used to resolve user expressions 2976 of the form "DOMAIN::NAME". For more details on what happens, see 2977 the comment before value_struct_elt_for_reference. */ 2978 2979 struct value * 2980 value_aggregate_elt (struct type *curtype, char *name, 2981 struct type *expect_type, int want_address, 2982 enum noside noside) 2983 { 2984 switch (TYPE_CODE (curtype)) 2985 { 2986 case TYPE_CODE_STRUCT: 2987 case TYPE_CODE_UNION: 2988 return value_struct_elt_for_reference (curtype, 0, curtype, 2989 name, expect_type, 2990 want_address, noside); 2991 case TYPE_CODE_NAMESPACE: 2992 return value_namespace_elt (curtype, name, 2993 want_address, noside); 2994 default: 2995 internal_error (__FILE__, __LINE__, 2996 _("non-aggregate type in value_aggregate_elt")); 2997 } 2998 } 2999 3000 /* Compares the two method/function types T1 and T2 for "equality" 3001 with respect to the the methods' parameters. If the types of the 3002 two parameter lists are the same, returns 1; 0 otherwise. This 3003 comparison may ignore any artificial parameters in T1 if 3004 SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip 3005 the first artificial parameter in T1, assumed to be a 'this' pointer. 3006 3007 The type T2 is expected to have come from make_params (in eval.c). */ 3008 3009 static int 3010 compare_parameters (struct type *t1, struct type *t2, int skip_artificial) 3011 { 3012 int start = 0; 3013 3014 if (TYPE_FIELD_ARTIFICIAL (t1, 0)) 3015 ++start; 3016 3017 /* If skipping artificial fields, find the first real field 3018 in T1. */ 3019 if (skip_artificial) 3020 { 3021 while (start < TYPE_NFIELDS (t1) 3022 && TYPE_FIELD_ARTIFICIAL (t1, start)) 3023 ++start; 3024 } 3025 3026 /* Now compare parameters */ 3027 3028 /* Special case: a method taking void. T1 will contain no 3029 non-artificial fields, and T2 will contain TYPE_CODE_VOID. */ 3030 if ((TYPE_NFIELDS (t1) - start) == 0 && TYPE_NFIELDS (t2) == 1 3031 && TYPE_CODE (TYPE_FIELD_TYPE (t2, 0)) == TYPE_CODE_VOID) 3032 return 1; 3033 3034 if ((TYPE_NFIELDS (t1) - start) == TYPE_NFIELDS (t2)) 3035 { 3036 int i; 3037 3038 for (i = 0; i < TYPE_NFIELDS (t2); ++i) 3039 { 3040 if (rank_one_type (TYPE_FIELD_TYPE (t1, start + i), 3041 TYPE_FIELD_TYPE (t2, i)) 3042 != 0) 3043 return 0; 3044 } 3045 3046 return 1; 3047 } 3048 3049 return 0; 3050 } 3051 3052 /* C++: Given an aggregate type CURTYPE, and a member name NAME, 3053 return the address of this member as a "pointer to member" type. 3054 If INTYPE is non-null, then it will be the type of the member we 3055 are looking for. This will help us resolve "pointers to member 3056 functions". This function is used to resolve user expressions of 3057 the form "DOMAIN::NAME". */ 3058 3059 static struct value * 3060 value_struct_elt_for_reference (struct type *domain, int offset, 3061 struct type *curtype, char *name, 3062 struct type *intype, 3063 int want_address, 3064 enum noside noside) 3065 { 3066 struct type *t = curtype; 3067 int i; 3068 struct value *v, *result; 3069 3070 if (TYPE_CODE (t) != TYPE_CODE_STRUCT 3071 && TYPE_CODE (t) != TYPE_CODE_UNION) 3072 error (_("Internal error: non-aggregate type to value_struct_elt_for_reference")); 3073 3074 for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--) 3075 { 3076 char *t_field_name = TYPE_FIELD_NAME (t, i); 3077 3078 if (t_field_name && strcmp (t_field_name, name) == 0) 3079 { 3080 if (field_is_static (&TYPE_FIELD (t, i))) 3081 { 3082 v = value_static_field (t, i); 3083 if (v == NULL) 3084 error (_("static field %s has been optimized out"), 3085 name); 3086 if (want_address) 3087 v = value_addr (v); 3088 return v; 3089 } 3090 if (TYPE_FIELD_PACKED (t, i)) 3091 error (_("pointers to bitfield members not allowed")); 3092 3093 if (want_address) 3094 return value_from_longest 3095 (lookup_memberptr_type (TYPE_FIELD_TYPE (t, i), domain), 3096 offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3)); 3097 else if (noside == EVAL_AVOID_SIDE_EFFECTS) 3098 return allocate_value (TYPE_FIELD_TYPE (t, i)); 3099 else 3100 error (_("Cannot reference non-static field \"%s\""), name); 3101 } 3102 } 3103 3104 /* C++: If it was not found as a data field, then try to return it 3105 as a pointer to a method. */ 3106 3107 /* Perform all necessary dereferencing. */ 3108 while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR) 3109 intype = TYPE_TARGET_TYPE (intype); 3110 3111 for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i) 3112 { 3113 char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i); 3114 char dem_opname[64]; 3115 3116 if (strncmp (t_field_name, "__", 2) == 0 3117 || strncmp (t_field_name, "op", 2) == 0 3118 || strncmp (t_field_name, "type", 4) == 0) 3119 { 3120 if (cplus_demangle_opname (t_field_name, 3121 dem_opname, DMGL_ANSI)) 3122 t_field_name = dem_opname; 3123 else if (cplus_demangle_opname (t_field_name, 3124 dem_opname, 0)) 3125 t_field_name = dem_opname; 3126 } 3127 if (t_field_name && strcmp (t_field_name, name) == 0) 3128 { 3129 int j; 3130 int len = TYPE_FN_FIELDLIST_LENGTH (t, i); 3131 struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i); 3132 3133 check_stub_method_group (t, i); 3134 3135 if (intype) 3136 { 3137 for (j = 0; j < len; ++j) 3138 { 3139 if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0) 3140 || compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 1)) 3141 break; 3142 } 3143 3144 if (j == len) 3145 error (_("no member function matches that type instantiation")); 3146 } 3147 else 3148 { 3149 int ii; 3150 3151 j = -1; 3152 for (ii = 0; ii < TYPE_FN_FIELDLIST_LENGTH (t, i); 3153 ++ii) 3154 { 3155 /* Skip artificial methods. This is necessary if, 3156 for example, the user wants to "print 3157 subclass::subclass" with only one user-defined 3158 constructor. There is no ambiguity in this 3159 case. */ 3160 if (TYPE_FN_FIELD_ARTIFICIAL (f, ii)) 3161 continue; 3162 3163 /* Desired method is ambiguous if more than one 3164 method is defined. */ 3165 if (j != -1) 3166 error (_("non-unique member `%s' requires type instantiation"), name); 3167 3168 j = ii; 3169 } 3170 } 3171 3172 if (TYPE_FN_FIELD_STATIC_P (f, j)) 3173 { 3174 struct symbol *s = 3175 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j), 3176 0, VAR_DOMAIN, 0); 3177 3178 if (s == NULL) 3179 return NULL; 3180 3181 if (want_address) 3182 return value_addr (read_var_value (s, 0)); 3183 else 3184 return read_var_value (s, 0); 3185 } 3186 3187 if (TYPE_FN_FIELD_VIRTUAL_P (f, j)) 3188 { 3189 if (want_address) 3190 { 3191 result = allocate_value 3192 (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j))); 3193 cplus_make_method_ptr (value_type (result), 3194 value_contents_writeable (result), 3195 TYPE_FN_FIELD_VOFFSET (f, j), 1); 3196 } 3197 else if (noside == EVAL_AVOID_SIDE_EFFECTS) 3198 return allocate_value (TYPE_FN_FIELD_TYPE (f, j)); 3199 else 3200 error (_("Cannot reference virtual member function \"%s\""), 3201 name); 3202 } 3203 else 3204 { 3205 struct symbol *s = 3206 lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j), 3207 0, VAR_DOMAIN, 0); 3208 3209 if (s == NULL) 3210 return NULL; 3211 3212 v = read_var_value (s, 0); 3213 if (!want_address) 3214 result = v; 3215 else 3216 { 3217 result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j))); 3218 cplus_make_method_ptr (value_type (result), 3219 value_contents_writeable (result), 3220 value_address (v), 0); 3221 } 3222 } 3223 return result; 3224 } 3225 } 3226 for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--) 3227 { 3228 struct value *v; 3229 int base_offset; 3230 3231 if (BASETYPE_VIA_VIRTUAL (t, i)) 3232 base_offset = 0; 3233 else 3234 base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8; 3235 v = value_struct_elt_for_reference (domain, 3236 offset + base_offset, 3237 TYPE_BASECLASS (t, i), 3238 name, intype, 3239 want_address, noside); 3240 if (v) 3241 return v; 3242 } 3243 3244 /* As a last chance, pretend that CURTYPE is a namespace, and look 3245 it up that way; this (frequently) works for types nested inside 3246 classes. */ 3247 3248 return value_maybe_namespace_elt (curtype, name, 3249 want_address, noside); 3250 } 3251 3252 /* C++: Return the member NAME of the namespace given by the type 3253 CURTYPE. */ 3254 3255 static struct value * 3256 value_namespace_elt (const struct type *curtype, 3257 char *name, int want_address, 3258 enum noside noside) 3259 { 3260 struct value *retval = value_maybe_namespace_elt (curtype, name, 3261 want_address, 3262 noside); 3263 3264 if (retval == NULL) 3265 error (_("No symbol \"%s\" in namespace \"%s\"."), 3266 name, TYPE_TAG_NAME (curtype)); 3267 3268 return retval; 3269 } 3270 3271 /* A helper function used by value_namespace_elt and 3272 value_struct_elt_for_reference. It looks up NAME inside the 3273 context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE 3274 is a class and NAME refers to a type in CURTYPE itself (as opposed 3275 to, say, some base class of CURTYPE). */ 3276 3277 static struct value * 3278 value_maybe_namespace_elt (const struct type *curtype, 3279 char *name, int want_address, 3280 enum noside noside) 3281 { 3282 const char *namespace_name = TYPE_TAG_NAME (curtype); 3283 struct symbol *sym; 3284 struct value *result; 3285 3286 sym = cp_lookup_symbol_namespace (namespace_name, name, 3287 get_selected_block (0), VAR_DOMAIN); 3288 3289 if (sym == NULL) 3290 { 3291 char *concatenated_name = alloca (strlen (namespace_name) + 2 3292 + strlen (name) + 1); 3293 3294 sprintf (concatenated_name, "%s::%s", namespace_name, name); 3295 sym = lookup_static_symbol_aux (concatenated_name, VAR_DOMAIN); 3296 } 3297 3298 if (sym == NULL) 3299 return NULL; 3300 else if ((noside == EVAL_AVOID_SIDE_EFFECTS) 3301 && (SYMBOL_CLASS (sym) == LOC_TYPEDEF)) 3302 result = allocate_value (SYMBOL_TYPE (sym)); 3303 else 3304 result = value_of_variable (sym, get_selected_block (0)); 3305 3306 if (result && want_address) 3307 result = value_addr (result); 3308 3309 return result; 3310 } 3311 3312 /* Given a pointer value V, find the real (RTTI) type of the object it 3313 points to. 3314 3315 Other parameters FULL, TOP, USING_ENC as with value_rtti_type() 3316 and refer to the values computed for the object pointed to. */ 3317 3318 struct type * 3319 value_rtti_target_type (struct value *v, int *full, 3320 int *top, int *using_enc) 3321 { 3322 struct value *target; 3323 3324 target = value_ind (v); 3325 3326 return value_rtti_type (target, full, top, using_enc); 3327 } 3328 3329 /* Given a value pointed to by ARGP, check its real run-time type, and 3330 if that is different from the enclosing type, create a new value 3331 using the real run-time type as the enclosing type (and of the same 3332 type as ARGP) and return it, with the embedded offset adjusted to 3333 be the correct offset to the enclosed object. RTYPE is the type, 3334 and XFULL, XTOP, and XUSING_ENC are the other parameters, computed 3335 by value_rtti_type(). If these are available, they can be supplied 3336 and a second call to value_rtti_type() is avoided. (Pass RTYPE == 3337 NULL if they're not available. */ 3338 3339 struct value * 3340 value_full_object (struct value *argp, 3341 struct type *rtype, 3342 int xfull, int xtop, 3343 int xusing_enc) 3344 { 3345 struct type *real_type; 3346 int full = 0; 3347 int top = -1; 3348 int using_enc = 0; 3349 struct value *new_val; 3350 3351 if (rtype) 3352 { 3353 real_type = rtype; 3354 full = xfull; 3355 top = xtop; 3356 using_enc = xusing_enc; 3357 } 3358 else 3359 real_type = value_rtti_type (argp, &full, &top, &using_enc); 3360 3361 /* If no RTTI data, or if object is already complete, do nothing. */ 3362 if (!real_type || real_type == value_enclosing_type (argp)) 3363 return argp; 3364 3365 /* If we have the full object, but for some reason the enclosing 3366 type is wrong, set it. */ 3367 /* pai: FIXME -- sounds iffy */ 3368 if (full) 3369 { 3370 argp = value_change_enclosing_type (argp, real_type); 3371 return argp; 3372 } 3373 3374 /* Check if object is in memory */ 3375 if (VALUE_LVAL (argp) != lval_memory) 3376 { 3377 warning (_("Couldn't retrieve complete object of RTTI type %s; object may be in register(s)."), 3378 TYPE_NAME (real_type)); 3379 3380 return argp; 3381 } 3382 3383 /* All other cases -- retrieve the complete object. */ 3384 /* Go back by the computed top_offset from the beginning of the 3385 object, adjusting for the embedded offset of argp if that's what 3386 value_rtti_type used for its computation. */ 3387 new_val = value_at_lazy (real_type, value_address (argp) - top + 3388 (using_enc ? 0 : value_embedded_offset (argp))); 3389 deprecated_set_value_type (new_val, value_type (argp)); 3390 set_value_embedded_offset (new_val, (using_enc 3391 ? top + value_embedded_offset (argp) 3392 : top)); 3393 return new_val; 3394 } 3395 3396 3397 /* Return the value of the local variable, if one exists. 3398 Flag COMPLAIN signals an error if the request is made in an 3399 inappropriate context. */ 3400 3401 struct value * 3402 value_of_local (const char *name, int complain) 3403 { 3404 struct symbol *func, *sym; 3405 struct block *b; 3406 struct value * ret; 3407 struct frame_info *frame; 3408 3409 if (complain) 3410 frame = get_selected_frame (_("no frame selected")); 3411 else 3412 { 3413 frame = deprecated_safe_get_selected_frame (); 3414 if (frame == 0) 3415 return 0; 3416 } 3417 3418 func = get_frame_function (frame); 3419 if (!func) 3420 { 3421 if (complain) 3422 error (_("no `%s' in nameless context"), name); 3423 else 3424 return 0; 3425 } 3426 3427 b = SYMBOL_BLOCK_VALUE (func); 3428 if (dict_empty (BLOCK_DICT (b))) 3429 { 3430 if (complain) 3431 error (_("no args, no `%s'"), name); 3432 else 3433 return 0; 3434 } 3435 3436 /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER 3437 symbol instead of the LOC_ARG one (if both exist). */ 3438 sym = lookup_block_symbol (b, name, VAR_DOMAIN); 3439 if (sym == NULL) 3440 { 3441 if (complain) 3442 error (_("current stack frame does not contain a variable named `%s'"), 3443 name); 3444 else 3445 return NULL; 3446 } 3447 3448 ret = read_var_value (sym, frame); 3449 if (ret == 0 && complain) 3450 error (_("`%s' argument unreadable"), name); 3451 return ret; 3452 } 3453 3454 /* C++/Objective-C: return the value of the class instance variable, 3455 if one exists. Flag COMPLAIN signals an error if the request is 3456 made in an inappropriate context. */ 3457 3458 struct value * 3459 value_of_this (int complain) 3460 { 3461 if (!current_language->la_name_of_this) 3462 return 0; 3463 return value_of_local (current_language->la_name_of_this, complain); 3464 } 3465 3466 /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH 3467 elements long, starting at LOWBOUND. The result has the same lower 3468 bound as the original ARRAY. */ 3469 3470 struct value * 3471 value_slice (struct value *array, int lowbound, int length) 3472 { 3473 struct type *slice_range_type, *slice_type, *range_type; 3474 LONGEST lowerbound, upperbound; 3475 struct value *slice; 3476 struct type *array_type; 3477 3478 array_type = check_typedef (value_type (array)); 3479 if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY 3480 && TYPE_CODE (array_type) != TYPE_CODE_STRING 3481 && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING) 3482 error (_("cannot take slice of non-array")); 3483 3484 range_type = TYPE_INDEX_TYPE (array_type); 3485 if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0) 3486 error (_("slice from bad array or bitstring")); 3487 3488 if (lowbound < lowerbound || length < 0 3489 || lowbound + length - 1 > upperbound) 3490 error (_("slice out of range")); 3491 3492 /* FIXME-type-allocation: need a way to free this type when we are 3493 done with it. */ 3494 slice_range_type = create_range_type ((struct type *) NULL, 3495 TYPE_TARGET_TYPE (range_type), 3496 lowbound, 3497 lowbound + length - 1); 3498 if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING) 3499 { 3500 int i; 3501 3502 slice_type = create_set_type ((struct type *) NULL, 3503 slice_range_type); 3504 TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING; 3505 slice = value_zero (slice_type, not_lval); 3506 3507 for (i = 0; i < length; i++) 3508 { 3509 int element = value_bit_index (array_type, 3510 value_contents (array), 3511 lowbound + i); 3512 3513 if (element < 0) 3514 error (_("internal error accessing bitstring")); 3515 else if (element > 0) 3516 { 3517 int j = i % TARGET_CHAR_BIT; 3518 3519 if (gdbarch_bits_big_endian (get_type_arch (array_type))) 3520 j = TARGET_CHAR_BIT - 1 - j; 3521 value_contents_raw (slice)[i / TARGET_CHAR_BIT] |= (1 << j); 3522 } 3523 } 3524 /* We should set the address, bitssize, and bitspos, so the 3525 slice can be used on the LHS, but that may require extensions 3526 to value_assign. For now, just leave as a non_lval. 3527 FIXME. */ 3528 } 3529 else 3530 { 3531 struct type *element_type = TYPE_TARGET_TYPE (array_type); 3532 LONGEST offset = 3533 (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type)); 3534 3535 slice_type = create_array_type ((struct type *) NULL, 3536 element_type, 3537 slice_range_type); 3538 TYPE_CODE (slice_type) = TYPE_CODE (array_type); 3539 3540 if (VALUE_LVAL (array) == lval_memory && value_lazy (array)) 3541 slice = allocate_value_lazy (slice_type); 3542 else 3543 { 3544 slice = allocate_value (slice_type); 3545 memcpy (value_contents_writeable (slice), 3546 value_contents (array) + offset, 3547 TYPE_LENGTH (slice_type)); 3548 } 3549 3550 set_value_component_location (slice, array); 3551 VALUE_FRAME_ID (slice) = VALUE_FRAME_ID (array); 3552 set_value_offset (slice, value_offset (array) + offset); 3553 } 3554 return slice; 3555 } 3556 3557 /* Create a value for a FORTRAN complex number. Currently most of the 3558 time values are coerced to COMPLEX*16 (i.e. a complex number 3559 composed of 2 doubles. This really should be a smarter routine 3560 that figures out precision inteligently as opposed to assuming 3561 doubles. FIXME: fmb */ 3562 3563 struct value * 3564 value_literal_complex (struct value *arg1, 3565 struct value *arg2, 3566 struct type *type) 3567 { 3568 struct value *val; 3569 struct type *real_type = TYPE_TARGET_TYPE (type); 3570 3571 val = allocate_value (type); 3572 arg1 = value_cast (real_type, arg1); 3573 arg2 = value_cast (real_type, arg2); 3574 3575 memcpy (value_contents_raw (val), 3576 value_contents (arg1), TYPE_LENGTH (real_type)); 3577 memcpy (value_contents_raw (val) + TYPE_LENGTH (real_type), 3578 value_contents (arg2), TYPE_LENGTH (real_type)); 3579 return val; 3580 } 3581 3582 /* Cast a value into the appropriate complex data type. */ 3583 3584 static struct value * 3585 cast_into_complex (struct type *type, struct value *val) 3586 { 3587 struct type *real_type = TYPE_TARGET_TYPE (type); 3588 3589 if (TYPE_CODE (value_type (val)) == TYPE_CODE_COMPLEX) 3590 { 3591 struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val)); 3592 struct value *re_val = allocate_value (val_real_type); 3593 struct value *im_val = allocate_value (val_real_type); 3594 3595 memcpy (value_contents_raw (re_val), 3596 value_contents (val), TYPE_LENGTH (val_real_type)); 3597 memcpy (value_contents_raw (im_val), 3598 value_contents (val) + TYPE_LENGTH (val_real_type), 3599 TYPE_LENGTH (val_real_type)); 3600 3601 return value_literal_complex (re_val, im_val, type); 3602 } 3603 else if (TYPE_CODE (value_type (val)) == TYPE_CODE_FLT 3604 || TYPE_CODE (value_type (val)) == TYPE_CODE_INT) 3605 return value_literal_complex (val, 3606 value_zero (real_type, not_lval), 3607 type); 3608 else 3609 error (_("cannot cast non-number to complex")); 3610 } 3611 3612 void 3613 _initialize_valops (void) 3614 { 3615 add_setshow_boolean_cmd ("overload-resolution", class_support, 3616 &overload_resolution, _("\ 3617 Set overload resolution in evaluating C++ functions."), _("\ 3618 Show overload resolution in evaluating C++ functions."), 3619 NULL, NULL, 3620 show_overload_resolution, 3621 &setlist, &showlist); 3622 overload_resolution = 1; 3623 } 3624