1 /* DWARF 2 debugging format support for GDB. 2 3 Copyright (C) 1994-2020 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 19 20 #ifndef DWARF2READ_H 21 #define DWARF2READ_H 22 23 #include <queue> 24 #include <unordered_map> 25 #include "dwarf2/comp-unit.h" 26 #include "dwarf2/index-cache.h" 27 #include "dwarf2/section.h" 28 #include "filename-seen-cache.h" 29 #include "gdb_obstack.h" 30 #include "gdbsupport/hash_enum.h" 31 #include "gdbsupport/function-view.h" 32 #include "psympriv.h" 33 34 /* Hold 'maintenance (set|show) dwarf' commands. */ 35 extern struct cmd_list_element *set_dwarf_cmdlist; 36 extern struct cmd_list_element *show_dwarf_cmdlist; 37 38 struct tu_stats 39 { 40 int nr_uniq_abbrev_tables; 41 int nr_symtabs; 42 int nr_symtab_sharers; 43 int nr_stmt_less_type_units; 44 int nr_all_type_units_reallocs; 45 }; 46 47 struct dwarf2_cu; 48 struct dwarf2_debug_sections; 49 struct dwarf2_per_cu_data; 50 struct mapped_index; 51 struct mapped_debug_names; 52 struct signatured_type; 53 struct type_unit_group; 54 55 /* One item on the queue of compilation units to read in full symbols 56 for. */ 57 struct dwarf2_queue_item 58 { dwarf2_queue_itemdwarf2_queue_item59 dwarf2_queue_item (dwarf2_per_cu_data *cu, dwarf2_per_objfile *per_objfile, 60 enum language lang) 61 : per_cu (cu), 62 per_objfile (per_objfile), 63 pretend_language (lang) 64 { 65 } 66 67 ~dwarf2_queue_item (); 68 69 DISABLE_COPY_AND_ASSIGN (dwarf2_queue_item); 70 71 dwarf2_per_cu_data *per_cu; 72 dwarf2_per_objfile *per_objfile; 73 enum language pretend_language; 74 }; 75 76 /* Some DWARF data can be shared across objfiles who share the same BFD, 77 this data is stored in this object. 78 79 Two dwarf2_per_objfile objects representing objfiles sharing the same BFD 80 will point to the same instance of dwarf2_per_bfd, unless the BFD requires 81 relocation. */ 82 83 struct dwarf2_per_bfd 84 { 85 /* Construct a dwarf2_per_bfd for OBFD. NAMES points to the 86 dwarf2 section names, or is NULL if the standard ELF names are 87 used. CAN_COPY is true for formats where symbol 88 interposition is possible and so symbol values must follow copy 89 relocation rules. */ 90 dwarf2_per_bfd (bfd *obfd, const dwarf2_debug_sections *names, bool can_copy); 91 92 ~dwarf2_per_bfd (); 93 94 DISABLE_COPY_AND_ASSIGN (dwarf2_per_bfd); 95 96 /* Return the CU/TU given its index. 97 98 This is intended for loops like: 99 100 for (i = 0; i < (dwarf2_per_bfd->n_comp_units 101 + dwarf2_per_bfd->n_type_units); ++i) 102 { 103 dwarf2_per_cu_data *per_cu = dwarf2_per_bfd->get_cutu (i); 104 105 ...; 106 } 107 */ 108 dwarf2_per_cu_data *get_cutu (int index); 109 110 /* Return the CU given its index. 111 This differs from get_cutu in that it's for when you know INDEX refers to a 112 CU. */ 113 dwarf2_per_cu_data *get_cu (int index); 114 115 /* Return the TU given its index. 116 This differs from get_cutu in that it's for when you know INDEX refers to a 117 TU. */ 118 signatured_type *get_tu (int index); 119 120 /* A convenience function to allocate a dwarf2_per_cu_data. The 121 returned object has its "index" field set properly. The object 122 is allocated on the dwarf2_per_bfd obstack. */ 123 dwarf2_per_cu_data *allocate_per_cu (); 124 125 /* A convenience function to allocate a signatured_type. The 126 returned object has its "index" field set properly. The object 127 is allocated on the dwarf2_per_bfd obstack. */ 128 signatured_type *allocate_signatured_type (); 129 130 /* Return the number of partial symtabs allocated with allocate_per_cu 131 and allocate_signatured_type so far. */ num_psymtabsdwarf2_per_bfd132 int num_psymtabs () const 133 { return m_num_psymtabs; } 134 135 private: 136 /* This function is mapped across the sections and remembers the 137 offset and size of each of the debugging sections we are 138 interested in. */ 139 void locate_sections (bfd *abfd, asection *sectp, 140 const dwarf2_debug_sections &names); 141 142 public: 143 /* The corresponding BFD. */ 144 bfd *obfd; 145 146 /* Objects that can be shared across objfiles are stored in this 147 obstack or on the psymtab obstack, while objects that are 148 objfile-specific are stored on the objfile obstack. */ 149 auto_obstack obstack; 150 151 dwarf2_section_info info {}; 152 dwarf2_section_info abbrev {}; 153 dwarf2_section_info line {}; 154 dwarf2_section_info loc {}; 155 dwarf2_section_info loclists {}; 156 dwarf2_section_info macinfo {}; 157 dwarf2_section_info macro {}; 158 dwarf2_section_info str {}; 159 dwarf2_section_info str_offsets {}; 160 dwarf2_section_info line_str {}; 161 dwarf2_section_info ranges {}; 162 dwarf2_section_info rnglists {}; 163 dwarf2_section_info addr {}; 164 dwarf2_section_info frame {}; 165 dwarf2_section_info eh_frame {}; 166 dwarf2_section_info gdb_index {}; 167 dwarf2_section_info debug_names {}; 168 dwarf2_section_info debug_aranges {}; 169 170 std::vector<dwarf2_section_info> types; 171 172 /* Table of all the compilation units. This is used to locate 173 the target compilation unit of a particular reference. */ 174 std::vector<dwarf2_per_cu_data *> all_comp_units; 175 176 /* The .debug_types-related CUs (TUs). */ 177 std::vector<signatured_type *> all_type_units; 178 179 /* Table of struct type_unit_group objects. 180 The hash key is the DW_AT_stmt_list value. */ 181 htab_up type_unit_groups; 182 183 /* A table mapping .debug_types signatures to its signatured_type entry. 184 This is NULL if the .debug_types section hasn't been read in yet. */ 185 htab_up signatured_types; 186 187 /* Type unit statistics, to see how well the scaling improvements 188 are doing. */ 189 struct tu_stats tu_stats {}; 190 191 /* A table mapping DW_AT_dwo_name values to struct dwo_file objects. 192 This is NULL if the table hasn't been allocated yet. */ 193 htab_up dwo_files; 194 195 /* True if we've checked for whether there is a DWP file. */ 196 bool dwp_checked = false; 197 198 /* The DWP file if there is one, or NULL. */ 199 std::unique_ptr<struct dwp_file> dwp_file; 200 201 /* The shared '.dwz' file, if one exists. This is used when the 202 original data was compressed using 'dwz -m'. */ 203 std::unique_ptr<struct dwz_file> dwz_file; 204 205 /* Whether copy relocations are supported by this object format. */ 206 bool can_copy; 207 208 /* A flag indicating whether this objfile has a section loaded at a 209 VMA of 0. */ 210 bool has_section_at_zero = false; 211 212 /* True if we are using the mapped index, 213 or we are faking it for OBJF_READNOW's sake. */ 214 bool using_index = false; 215 216 /* The mapped index, or NULL if .gdb_index is missing or not being used. */ 217 std::unique_ptr<mapped_index> index_table; 218 219 /* The mapped index, or NULL if .debug_names is missing or not being used. */ 220 std::unique_ptr<mapped_debug_names> debug_names_table; 221 222 /* When using index_table, this keeps track of all quick_file_names entries. 223 TUs typically share line table entries with a CU, so we maintain a 224 separate table of all line table entries to support the sharing. 225 Note that while there can be way more TUs than CUs, we've already 226 sorted all the TUs into "type unit groups", grouped by their 227 DW_AT_stmt_list value. Therefore the only sharing done here is with a 228 CU and its associated TU group if there is one. */ 229 htab_up quick_file_names_table; 230 231 /* Set during partial symbol reading, to prevent queueing of full 232 symbols. */ 233 bool reading_partial_symbols = false; 234 235 /* The CUs we recently read. */ 236 std::vector<dwarf2_per_cu_data *> just_read_cus; 237 238 /* Table containing all filenames. This is an optional because the 239 table is lazily constructed on first access. */ 240 gdb::optional<filename_seen_cache> filenames_cache; 241 242 /* If we loaded the index from an external file, this contains the 243 resources associated to the open file, memory mapping, etc. */ 244 std::unique_ptr<index_cache_resource> index_cache_res; 245 246 /* Mapping from abstract origin DIE to concrete DIEs that reference it as 247 DW_AT_abstract_origin. */ 248 std::unordered_map<sect_offset, std::vector<sect_offset>, 249 gdb::hash_enum<sect_offset>> 250 abstract_to_concrete; 251 252 /* CUs that are queued to be read. */ 253 std::queue<dwarf2_queue_item> queue; 254 255 /* We keep a separate reference to the partial symtabs, in case we 256 are sharing them between objfiles. This is only set after 257 partial symbols have been read the first time. */ 258 std::shared_ptr<psymtab_storage> partial_symtabs; 259 260 private: 261 262 /* The total number of per_cu and signatured_type objects that have 263 been created so far for this reader. */ 264 size_t m_num_psymtabs = 0; 265 }; 266 267 /* This is the per-objfile data associated with a type_unit_group. */ 268 269 struct type_unit_group_unshareable 270 { 271 /* The compunit symtab. 272 Type units in a group needn't all be defined in the same source file, 273 so we create an essentially anonymous symtab as the compunit symtab. */ 274 struct compunit_symtab *compunit_symtab = nullptr; 275 276 /* The number of symtabs from the line header. 277 The value here must match line_header.num_file_names. */ 278 unsigned int num_symtabs = 0; 279 280 /* The symbol tables for this TU (obtained from the files listed in 281 DW_AT_stmt_list). 282 WARNING: The order of entries here must match the order of entries 283 in the line header. After the first TU using this type_unit_group, the 284 line header for the subsequent TUs is recreated from this. This is done 285 because we need to use the same symtabs for each TU using the same 286 DW_AT_stmt_list value. Also note that symtabs may be repeated here, 287 there's no guarantee the line header doesn't have duplicate entries. */ 288 struct symtab **symtabs = nullptr; 289 }; 290 291 /* Collection of data recorded per objfile. 292 This hangs off of dwarf2_objfile_data_key. 293 294 Some DWARF data cannot (currently) be shared across objfiles. Such 295 data is stored in this object. */ 296 297 struct dwarf2_per_objfile 298 { dwarf2_per_objfiledwarf2_per_objfile299 dwarf2_per_objfile (struct objfile *objfile, dwarf2_per_bfd *per_bfd) 300 : objfile (objfile), per_bfd (per_bfd) 301 {} 302 303 ~dwarf2_per_objfile (); 304 305 /* Return pointer to string at .debug_line_str offset as read from BUF. 306 BUF is assumed to be in a compilation unit described by CU_HEADER. 307 Return *BYTES_READ_PTR count of bytes read from BUF. */ 308 const char *read_line_string (const gdb_byte *buf, 309 const struct comp_unit_head *cu_header, 310 unsigned int *bytes_read_ptr); 311 312 /* Resize the M_SYMTABS vector to the needed size (the number of partial 313 symtabs allocated by the per-bfd). */ resize_symtabsdwarf2_per_objfile314 void resize_symtabs () 315 { 316 /* The symtabs vector should only grow, not shrink. */ 317 gdb_assert (per_bfd->num_psymtabs () >= m_symtabs.size ()); 318 319 m_symtabs.resize (per_bfd->num_psymtabs ()); 320 } 321 322 /* Return true if the symtab corresponding to PER_CU has been set, 323 false otherwise. */ 324 bool symtab_set_p (const dwarf2_per_cu_data *per_cu) const; 325 326 /* Return the compunit_symtab associated to PER_CU, if it has been created. */ 327 compunit_symtab *get_symtab (const dwarf2_per_cu_data *per_cu) const; 328 329 /* Set the compunit_symtab associated to PER_CU. */ 330 void set_symtab (const dwarf2_per_cu_data *per_cu, compunit_symtab *symtab); 331 332 /* Get the type_unit_group_unshareable corresponding to TU_GROUP. If one 333 does not exist, create it. */ 334 type_unit_group_unshareable *get_type_unit_group_unshareable 335 (type_unit_group *tu_group); 336 337 struct type *get_type_for_signatured_type (signatured_type *sig_type) const; 338 339 void set_type_for_signatured_type (signatured_type *sig_type, 340 struct type *type); 341 342 /* Find an integer type SIZE_IN_BYTES bytes in size and return it. 343 UNSIGNED_P controls if the integer is unsigned or not. */ 344 struct type *int_type (int size_in_bytes, bool unsigned_p) const; 345 346 /* Get the dwarf2_cu matching PER_CU for this objfile. */ 347 dwarf2_cu *get_cu (dwarf2_per_cu_data *per_cu); 348 349 /* Set the dwarf2_cu matching PER_CU for this objfile. */ 350 void set_cu (dwarf2_per_cu_data *per_cu, dwarf2_cu *cu); 351 352 /* Remove/free the dwarf2_cu matching PER_CU for this objfile. */ 353 void remove_cu (dwarf2_per_cu_data *per_cu); 354 355 /* Free all cached compilation units. */ 356 void remove_all_cus (); 357 358 /* Increase the age counter on each CU compilation unit and free 359 any that are too old. */ 360 void age_comp_units (); 361 362 /* Back link. */ 363 struct objfile *objfile; 364 365 /* Pointer to the data that is (possibly) shared between this objfile and 366 other objfiles backed by the same BFD. */ 367 struct dwarf2_per_bfd *per_bfd; 368 369 /* Table mapping type DIEs to their struct type *. 370 This is nullptr if not allocated yet. 371 The mapping is done via (CU/TU + DIE offset) -> type. */ 372 htab_up die_type_hash; 373 374 /* Table containing line_header indexed by offset and offset_in_dwz. */ 375 htab_up line_header_hash; 376 377 private: 378 /* Hold the corresponding compunit_symtab for each CU or TU. This 379 is indexed by dwarf2_per_cu_data::index. A NULL value means 380 that the CU/TU has not been expanded yet. */ 381 std::vector<compunit_symtab *> m_symtabs; 382 383 /* Map from a type unit group to the corresponding unshared 384 structure. */ 385 typedef std::unique_ptr<type_unit_group_unshareable> 386 type_unit_group_unshareable_up; 387 388 std::unordered_map<type_unit_group *, type_unit_group_unshareable_up> 389 m_type_units; 390 391 /* Map from signatured types to the corresponding struct type. */ 392 std::unordered_map<signatured_type *, struct type *> m_type_map; 393 394 /* Map from the objfile-independent dwarf2_per_cu_data instances to the 395 corresponding objfile-dependent dwarf2_cu instances. */ 396 std::unordered_map<dwarf2_per_cu_data *, dwarf2_cu *> m_dwarf2_cus; 397 }; 398 399 /* Get the dwarf2_per_objfile associated to OBJFILE. */ 400 401 dwarf2_per_objfile *get_dwarf2_per_objfile (struct objfile *objfile); 402 403 /* A partial symtab specialized for DWARF. */ 404 struct dwarf2_psymtab : public partial_symtab 405 { dwarf2_psymtabdwarf2_psymtab406 dwarf2_psymtab (const char *filename, struct objfile *objfile, 407 dwarf2_per_cu_data *per_cu) 408 : partial_symtab (filename, objfile, 0), 409 per_cu_data (per_cu) 410 { 411 } 412 413 void read_symtab (struct objfile *) override; 414 void expand_psymtab (struct objfile *) override; 415 bool readin_p (struct objfile *) const override; 416 compunit_symtab *get_compunit_symtab (struct objfile *) const override; 417 418 struct dwarf2_per_cu_data *per_cu_data; 419 }; 420 421 /* Persistent data held for a compilation unit, even when not 422 processing it. We put a pointer to this structure in the 423 psymtab. */ 424 425 struct dwarf2_per_cu_data 426 { 427 /* The start offset and length of this compilation unit. 428 NOTE: Unlike comp_unit_head.length, this length includes 429 initial_length_size. 430 If the DIE refers to a DWO file, this is always of the original die, 431 not the DWO file. */ 432 sect_offset sect_off; 433 unsigned int length; 434 435 /* DWARF standard version this data has been read from (such as 4 or 5). */ 436 short dwarf_version; 437 438 /* Flag indicating this compilation unit will be read in before 439 any of the current compilation units are processed. */ 440 unsigned int queued : 1; 441 442 /* This flag will be set when reading partial DIEs if we need to load 443 absolutely all DIEs for this compilation unit, instead of just the ones 444 we think are interesting. It gets set if we look for a DIE in the 445 hash table and don't find it. */ 446 unsigned int load_all_dies : 1; 447 448 /* Non-zero if this CU is from .debug_types. 449 Struct dwarf2_per_cu_data is contained in struct signatured_type iff 450 this is non-zero. */ 451 unsigned int is_debug_types : 1; 452 453 /* Non-zero if this CU is from the .dwz file. */ 454 unsigned int is_dwz : 1; 455 456 /* Non-zero if reading a TU directly from a DWO file, bypassing the stub. 457 This flag is only valid if is_debug_types is true. 458 We can't read a CU directly from a DWO file: There are required 459 attributes in the stub. */ 460 unsigned int reading_dwo_directly : 1; 461 462 /* Non-zero if the TU has been read. 463 This is used to assist the "Stay in DWO Optimization" for Fission: 464 When reading a DWO, it's faster to read TUs from the DWO instead of 465 fetching them from random other DWOs (due to comdat folding). 466 If the TU has already been read, the optimization is unnecessary 467 (and unwise - we don't want to change where gdb thinks the TU lives 468 "midflight"). 469 This flag is only valid if is_debug_types is true. */ 470 unsigned int tu_read : 1; 471 472 /* Our index in the unshared "symtabs" vector. */ 473 unsigned index; 474 475 /* The section this CU/TU lives in. 476 If the DIE refers to a DWO file, this is always the original die, 477 not the DWO file. */ 478 struct dwarf2_section_info *section; 479 480 /* The unit type of this CU. */ 481 enum dwarf_unit_type unit_type; 482 483 /* The language of this CU. */ 484 enum language lang; 485 486 /* Backlink to the owner of this. */ 487 dwarf2_per_bfd *per_bfd; 488 489 /* DWARF header of this CU. Note that dwarf2_cu reads its own version of the 490 header, which may differ from this one, since it may pass rcuh_kind::TYPE 491 to read_comp_unit_head, whereas for dwarf2_per_cu_data we always pass 492 rcuh_kind::COMPILE. 493 494 Don't access this field directly, use the get_header method instead. It 495 should be private, but we can't make it private at the moment. */ 496 mutable comp_unit_head m_header; 497 498 /* True if HEADER has been read in. 499 500 Don't access this field directly. It should be private, but we can't make 501 it private at the moment. */ 502 mutable bool m_header_read_in; 503 504 /* When dwarf2_per_bfd::using_index is true, the 'quick' field 505 is active. Otherwise, the 'psymtab' field is active. */ 506 union 507 { 508 /* The partial symbol table associated with this compilation unit, 509 or NULL for unread partial units. */ 510 dwarf2_psymtab *psymtab; 511 512 /* Data needed by the "quick" functions. */ 513 struct dwarf2_per_cu_quick_data *quick; 514 } v; 515 516 /* The CUs we import using DW_TAG_imported_unit. This is filled in 517 while reading psymtabs, used to compute the psymtab dependencies, 518 and then cleared. Then it is filled in again while reading full 519 symbols, and only deleted when the objfile is destroyed. 520 521 This is also used to work around a difference between the way gold 522 generates .gdb_index version <=7 and the way gdb does. Arguably this 523 is a gold bug. For symbols coming from TUs, gold records in the index 524 the CU that includes the TU instead of the TU itself. This breaks 525 dw2_lookup_symbol: It assumes that if the index says symbol X lives 526 in CU/TU Y, then one need only expand Y and a subsequent lookup in Y 527 will find X. Alas TUs live in their own symtab, so after expanding CU Y 528 we need to look in TU Z to find X. Fortunately, this is akin to 529 DW_TAG_imported_unit, so we just use the same mechanism: For 530 .gdb_index version <=7 this also records the TUs that the CU referred 531 to. Concurrently with this change gdb was modified to emit version 8 532 indices so we only pay a price for gold generated indices. 533 http://sourceware.org/bugzilla/show_bug.cgi?id=15021. 534 535 This currently needs to be a public member due to how 536 dwarf2_per_cu_data is allocated and used. Ideally in future things 537 could be refactored to make this private. Until then please try to 538 avoid direct access to this member, and instead use the helper 539 functions above. */ 540 std::vector <dwarf2_per_cu_data *> *imported_symtabs; 541 542 /* Return true of IMPORTED_SYMTABS is empty or not yet allocated. */ imported_symtabs_emptydwarf2_per_cu_data543 bool imported_symtabs_empty () const 544 { 545 return (imported_symtabs == nullptr || imported_symtabs->empty ()); 546 } 547 548 /* Push P to the back of IMPORTED_SYMTABS, allocated IMPORTED_SYMTABS 549 first if required. */ imported_symtabs_pushdwarf2_per_cu_data550 void imported_symtabs_push (dwarf2_per_cu_data *p) 551 { 552 if (imported_symtabs == nullptr) 553 imported_symtabs = new std::vector <dwarf2_per_cu_data *>; 554 imported_symtabs->push_back (p); 555 } 556 557 /* Return the size of IMPORTED_SYMTABS if it is allocated, otherwise 558 return 0. */ imported_symtabs_sizedwarf2_per_cu_data559 size_t imported_symtabs_size () const 560 { 561 if (imported_symtabs == nullptr) 562 return 0; 563 return imported_symtabs->size (); 564 } 565 566 /* Delete IMPORTED_SYMTABS and set the pointer back to nullptr. */ imported_symtabs_freedwarf2_per_cu_data567 void imported_symtabs_free () 568 { 569 delete imported_symtabs; 570 imported_symtabs = nullptr; 571 } 572 573 /* Get the header of this per_cu, reading it if necessary. */ 574 const comp_unit_head *get_header () const; 575 576 /* Return the address size given in the compilation unit header for 577 this CU. */ 578 int addr_size () const; 579 580 /* Return the offset size given in the compilation unit header for 581 this CU. */ 582 int offset_size () const; 583 584 /* Return the DW_FORM_ref_addr size given in the compilation unit 585 header for this CU. */ 586 int ref_addr_size () const; 587 588 /* Return DWARF version number of this CU. */ versiondwarf2_per_cu_data589 short version () const 590 { 591 return dwarf_version; 592 } 593 594 /* A type unit group has a per_cu object that is recognized by 595 having no section. */ type_unit_group_pdwarf2_per_cu_data596 bool type_unit_group_p () const 597 { 598 return section == nullptr; 599 } 600 }; 601 602 /* Entry in the signatured_types hash table. */ 603 604 struct signatured_type 605 { 606 /* The "per_cu" object of this type. 607 This struct is used iff per_cu.is_debug_types. 608 N.B.: This is the first member so that it's easy to convert pointers 609 between them. */ 610 struct dwarf2_per_cu_data per_cu; 611 612 /* The type's signature. */ 613 ULONGEST signature; 614 615 /* Offset in the TU of the type's DIE, as read from the TU header. 616 If this TU is a DWO stub and the definition lives in a DWO file 617 (specified by DW_AT_GNU_dwo_name), this value is unusable. */ 618 cu_offset type_offset_in_tu; 619 620 /* Offset in the section of the type's DIE. 621 If the definition lives in a DWO file, this is the offset in the 622 .debug_types.dwo section. 623 The value is zero until the actual value is known. 624 Zero is otherwise not a valid section offset. */ 625 sect_offset type_offset_in_section; 626 627 /* Type units are grouped by their DW_AT_stmt_list entry so that they 628 can share them. This points to the containing symtab. */ 629 struct type_unit_group *type_unit_group; 630 631 /* Containing DWO unit. 632 This field is valid iff per_cu.reading_dwo_directly. */ 633 struct dwo_unit *dwo_unit; 634 }; 635 636 /* Open the separate '.dwz' debug file, if needed. Return NULL if 637 there is no .gnu_debugaltlink section in the file. Error if there 638 is such a section but the file cannot be found. */ 639 640 extern dwz_file *dwarf2_get_dwz_file (dwarf2_per_bfd *per_bfd); 641 642 /* Return the type of the DIE at DIE_OFFSET in the CU named by 643 PER_CU. */ 644 645 struct type *dwarf2_get_die_type (cu_offset die_offset, 646 dwarf2_per_cu_data *per_cu, 647 dwarf2_per_objfile *per_objfile); 648 649 /* Given an index in .debug_addr, fetch the value. 650 NOTE: This can be called during dwarf expression evaluation, 651 long after the debug information has been read, and thus per_cu->cu 652 may no longer exist. */ 653 654 CORE_ADDR dwarf2_read_addr_index (dwarf2_per_cu_data *per_cu, 655 dwarf2_per_objfile *per_objfile, 656 unsigned int addr_index); 657 658 /* Return DWARF block referenced by DW_AT_location of DIE at SECT_OFF at PER_CU. 659 Returned value is intended for DW_OP_call*. Returned 660 dwarf2_locexpr_baton->data has lifetime of 661 PER_CU->DWARF2_PER_OBJFILE->OBJFILE. */ 662 663 struct dwarf2_locexpr_baton dwarf2_fetch_die_loc_sect_off 664 (sect_offset sect_off, dwarf2_per_cu_data *per_cu, 665 dwarf2_per_objfile *per_objfile, 666 gdb::function_view<CORE_ADDR ()> get_frame_pc, 667 bool resolve_abstract_p = false); 668 669 /* Like dwarf2_fetch_die_loc_sect_off, but take a CU 670 offset. */ 671 672 struct dwarf2_locexpr_baton dwarf2_fetch_die_loc_cu_off 673 (cu_offset offset_in_cu, dwarf2_per_cu_data *per_cu, 674 dwarf2_per_objfile *per_objfile, 675 gdb::function_view<CORE_ADDR ()> get_frame_pc); 676 677 /* If the DIE at SECT_OFF in PER_CU has a DW_AT_const_value, return a 678 pointer to the constant bytes and set LEN to the length of the 679 data. If memory is needed, allocate it on OBSTACK. If the DIE 680 does not have a DW_AT_const_value, return NULL. */ 681 682 extern const gdb_byte *dwarf2_fetch_constant_bytes 683 (sect_offset sect_off, dwarf2_per_cu_data *per_cu, 684 dwarf2_per_objfile *per_objfile, obstack *obstack, 685 LONGEST *len); 686 687 /* Return the type of the die at SECT_OFF in PER_CU. Return NULL if no 688 valid type for this die is found. */ 689 690 struct type *dwarf2_fetch_die_type_sect_off 691 (sect_offset sect_off, dwarf2_per_cu_data *per_cu, 692 dwarf2_per_objfile *per_objfile); 693 694 /* When non-zero, dump line number entries as they are read in. */ 695 extern unsigned int dwarf_line_debug; 696 697 #endif /* DWARF2READ_H */ 698