| 1 | // object.h -- support for an object file for linking in gold -*- C++ -*- |
| 2 | |
| 3 | // Copyright (C) 2006-2020 Free Software Foundation, Inc. |
| 4 | // Written by Ian Lance Taylor <iant@google.com>. |
| 5 | |
| 6 | // This file is part of gold. |
| 7 | |
| 8 | // This program is free software; you can redistribute it and/or modify |
| 9 | // it under the terms of the GNU General Public License as published by |
| 10 | // the Free Software Foundation; either version 3 of the License, or |
| 11 | // (at your option) any later version. |
| 12 | |
| 13 | // This program is distributed in the hope that it will be useful, |
| 14 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | // GNU General Public License for more details. |
| 17 | |
| 18 | // You should have received a copy of the GNU General Public License |
| 19 | // along with this program; if not, write to the Free Software |
| 20 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| 21 | // MA 02110-1301, USA. |
| 22 | |
| 23 | #ifndef GOLD_OBJECT_H |
| 24 | #define GOLD_OBJECT_H |
| 25 | |
| 26 | #include <string> |
| 27 | #include <vector> |
| 28 | |
| 29 | #include "elfcpp.h" |
| 30 | #include "elfcpp_file.h" |
| 31 | #include "fileread.h" |
| 32 | #include "target.h" |
| 33 | #include "archive.h" |
| 34 | |
| 35 | namespace gold |
| 36 | { |
| 37 | |
| 38 | class General_options; |
| 39 | class Task; |
| 40 | class Cref; |
| 41 | class Layout; |
| 42 | class Kept_section; |
| 43 | class Output_data; |
| 44 | class Output_section; |
| 45 | class Output_section_data; |
| 46 | class Output_file; |
| 47 | class Output_symtab_xindex; |
| 48 | class Pluginobj; |
| 49 | class Dynobj; |
| 50 | class Object_merge_map; |
| 51 | class Relocatable_relocs; |
| 52 | struct Symbols_data; |
| 53 | |
| 54 | template<typename Stringpool_char> |
| 55 | class Stringpool_template; |
| 56 | |
| 57 | // Data to pass from read_symbols() to add_symbols(). |
| 58 | |
| 59 | struct Read_symbols_data |
| 60 | { |
| 61 | Read_symbols_data() |
| 62 | : section_headers(NULL), section_names(NULL), symbols(NULL), |
| 63 | symbol_names(NULL), versym(NULL), verdef(NULL), verneed(NULL) |
| 64 | { } |
| 65 | |
| 66 | ~Read_symbols_data(); |
| 67 | |
| 68 | // Section headers. |
| 69 | File_view* section_headers; |
| 70 | // Section names. |
| 71 | File_view* section_names; |
| 72 | // Size of section name data in bytes. |
| 73 | section_size_type section_names_size; |
| 74 | // Symbol data. |
| 75 | File_view* symbols; |
| 76 | // Size of symbol data in bytes. |
| 77 | section_size_type symbols_size; |
| 78 | // Offset of external symbols within symbol data. This structure |
| 79 | // sometimes contains only external symbols, in which case this will |
| 80 | // be zero. Sometimes it contains all symbols. |
| 81 | section_offset_type external_symbols_offset; |
| 82 | // Symbol names. |
| 83 | File_view* symbol_names; |
| 84 | // Size of symbol name data in bytes. |
| 85 | section_size_type symbol_names_size; |
| 86 | |
| 87 | // Version information. This is only used on dynamic objects. |
| 88 | // Version symbol data (from SHT_GNU_versym section). |
| 89 | File_view* versym; |
| 90 | section_size_type versym_size; |
| 91 | // Version definition data (from SHT_GNU_verdef section). |
| 92 | File_view* verdef; |
| 93 | section_size_type verdef_size; |
| 94 | unsigned int verdef_info; |
| 95 | // Needed version data (from SHT_GNU_verneed section). |
| 96 | File_view* verneed; |
| 97 | section_size_type verneed_size; |
| 98 | unsigned int verneed_info; |
| 99 | }; |
| 100 | |
| 101 | // Information used to print error messages. |
| 102 | |
| 103 | struct Symbol_location_info |
| 104 | { |
| 105 | std::string source_file; |
| 106 | std::string enclosing_symbol_name; |
| 107 | elfcpp::STT enclosing_symbol_type; |
| 108 | }; |
| 109 | |
| 110 | // Data about a single relocation section. This is read in |
| 111 | // read_relocs and processed in scan_relocs. |
| 112 | |
| 113 | struct Section_relocs |
| 114 | { |
| 115 | Section_relocs() |
| 116 | : contents(NULL) |
| 117 | { } |
| 118 | |
| 119 | ~Section_relocs() |
| 120 | { delete this->contents; } |
| 121 | |
| 122 | // Index of reloc section. |
| 123 | unsigned int reloc_shndx; |
| 124 | // Index of section that relocs apply to. |
| 125 | unsigned int data_shndx; |
| 126 | // Contents of reloc section. |
| 127 | File_view* contents; |
| 128 | // Reloc section type. |
| 129 | unsigned int sh_type; |
| 130 | // Number of reloc entries. |
| 131 | size_t reloc_count; |
| 132 | // Output section. |
| 133 | Output_section* output_section; |
| 134 | // Whether this section has special handling for offsets. |
| 135 | bool needs_special_offset_handling; |
| 136 | // Whether the data section is allocated (has the SHF_ALLOC flag set). |
| 137 | bool is_data_section_allocated; |
| 138 | }; |
| 139 | |
| 140 | // Relocations in an object file. This is read in read_relocs and |
| 141 | // processed in scan_relocs. |
| 142 | |
| 143 | struct Read_relocs_data |
| 144 | { |
| 145 | Read_relocs_data() |
| 146 | : local_symbols(NULL) |
| 147 | { } |
| 148 | |
| 149 | ~Read_relocs_data() |
| 150 | { delete this->local_symbols; } |
| 151 | |
| 152 | typedef std::vector<Section_relocs> Relocs_list; |
| 153 | // The relocations. |
| 154 | Relocs_list relocs; |
| 155 | // The local symbols. |
| 156 | File_view* local_symbols; |
| 157 | }; |
| 158 | |
| 159 | // The Xindex class manages section indexes for objects with more than |
| 160 | // 0xff00 sections. |
| 161 | |
| 162 | class Xindex |
| 163 | { |
| 164 | public: |
| 165 | Xindex(int large_shndx_offset) |
| 166 | : large_shndx_offset_(large_shndx_offset), symtab_xindex_() |
| 167 | { } |
| 168 | |
| 169 | // Initialize the symtab_xindex_ array, given the object and the |
| 170 | // section index of the symbol table to use. |
| 171 | template<int size, bool big_endian> |
| 172 | void |
| 173 | initialize_symtab_xindex(Object*, unsigned int symtab_shndx); |
| 174 | |
| 175 | // Read in the symtab_xindex_ array, given its section index. |
| 176 | // PSHDRS may optionally point to the section headers. |
| 177 | template<int size, bool big_endian> |
| 178 | void |
| 179 | read_symtab_xindex(Object*, unsigned int xindex_shndx, |
| 180 | const unsigned char* pshdrs); |
| 181 | |
| 182 | // Symbol SYMNDX in OBJECT has a section of SHN_XINDEX; return the |
| 183 | // real section index. |
| 184 | unsigned int |
| 185 | sym_xindex_to_shndx(Object* object, unsigned int symndx); |
| 186 | |
| 187 | private: |
| 188 | // The type of the array giving the real section index for symbols |
| 189 | // whose st_shndx field holds SHN_XINDEX. |
| 190 | typedef std::vector<unsigned int> Symtab_xindex; |
| 191 | |
| 192 | // Adjust a section index if necessary. This should only be called |
| 193 | // for ordinary section indexes. |
| 194 | unsigned int |
| 195 | adjust_shndx(unsigned int shndx) |
| 196 | { |
| 197 | if (shndx >= elfcpp::SHN_LORESERVE) |
| 198 | shndx += this->large_shndx_offset_; |
| 199 | return shndx; |
| 200 | } |
| 201 | |
| 202 | // Adjust to apply to large section indexes. |
| 203 | int large_shndx_offset_; |
| 204 | // The data from the SHT_SYMTAB_SHNDX section. |
| 205 | Symtab_xindex symtab_xindex_; |
| 206 | }; |
| 207 | |
| 208 | // A GOT offset list. A symbol may have more than one GOT offset |
| 209 | // (e.g., when mixing modules compiled with two different TLS models), |
| 210 | // but will usually have at most one. GOT_TYPE identifies the type of |
| 211 | // GOT entry; its values are specific to each target. |
| 212 | |
| 213 | class Got_offset_list |
| 214 | { |
| 215 | public: |
| 216 | Got_offset_list() |
| 217 | : got_type_(-1U), got_offset_(0), got_next_(NULL) |
| 218 | { } |
| 219 | |
| 220 | Got_offset_list(unsigned int got_type, unsigned int got_offset) |
| 221 | : got_type_(got_type), got_offset_(got_offset), got_next_(NULL) |
| 222 | { } |
| 223 | |
| 224 | ~Got_offset_list() |
| 225 | { |
| 226 | if (this->got_next_ != NULL) |
| 227 | { |
| 228 | delete this->got_next_; |
| 229 | this->got_next_ = NULL; |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | // Initialize the fields to their default values. |
| 234 | void |
| 235 | init() |
| 236 | { |
| 237 | this->got_type_ = -1U; |
| 238 | this->got_offset_ = 0; |
| 239 | this->got_next_ = NULL; |
| 240 | } |
| 241 | |
| 242 | // Set the offset for the GOT entry of type GOT_TYPE. |
| 243 | void |
| 244 | set_offset(unsigned int got_type, unsigned int got_offset) |
| 245 | { |
| 246 | if (this->got_type_ == -1U) |
| 247 | { |
| 248 | this->got_type_ = got_type; |
| 249 | this->got_offset_ = got_offset; |
| 250 | } |
| 251 | else |
| 252 | { |
| 253 | for (Got_offset_list* g = this; g != NULL; g = g->got_next_) |
| 254 | { |
| 255 | if (g->got_type_ == got_type) |
| 256 | { |
| 257 | g->got_offset_ = got_offset; |
| 258 | return; |
| 259 | } |
| 260 | } |
| 261 | Got_offset_list* g = new Got_offset_list(got_type, got_offset); |
| 262 | g->got_next_ = this->got_next_; |
| 263 | this->got_next_ = g; |
| 264 | } |
| 265 | } |
| 266 | |
| 267 | // Return the offset for a GOT entry of type GOT_TYPE. |
| 268 | unsigned int |
| 269 | get_offset(unsigned int got_type) const |
| 270 | { |
| 271 | for (const Got_offset_list* g = this; g != NULL; g = g->got_next_) |
| 272 | { |
| 273 | if (g->got_type_ == got_type) |
| 274 | return g->got_offset_; |
| 275 | } |
| 276 | return -1U; |
| 277 | } |
| 278 | |
| 279 | // Return a pointer to the list, or NULL if the list is empty. |
| 280 | const Got_offset_list* |
| 281 | get_list() const |
| 282 | { |
| 283 | if (this->got_type_ == -1U) |
| 284 | return NULL; |
| 285 | return this; |
| 286 | } |
| 287 | |
| 288 | // Abstract visitor class for iterating over GOT offsets. |
| 289 | class Visitor |
| 290 | { |
| 291 | public: |
| 292 | Visitor() |
| 293 | { } |
| 294 | |
| 295 | virtual |
| 296 | ~Visitor() |
| 297 | { } |
| 298 | |
| 299 | virtual void |
| 300 | visit(unsigned int, unsigned int) = 0; |
| 301 | }; |
| 302 | |
| 303 | // Loop over all GOT offset entries, calling a visitor class V for each. |
| 304 | void |
| 305 | for_all_got_offsets(Visitor* v) const |
| 306 | { |
| 307 | if (this->got_type_ == -1U) |
| 308 | return; |
| 309 | for (const Got_offset_list* g = this; g != NULL; g = g->got_next_) |
| 310 | v->visit(g->got_type_, g->got_offset_); |
| 311 | } |
| 312 | |
| 313 | private: |
| 314 | unsigned int got_type_; |
| 315 | unsigned int got_offset_; |
| 316 | Got_offset_list* got_next_; |
| 317 | }; |
| 318 | |
| 319 | // The Local_got_entry_key used to index the GOT offsets for local |
| 320 | // non-TLS symbols, and tp-relative offsets for TLS symbols. |
| 321 | |
| 322 | class Local_got_entry_key |
| 323 | { |
| 324 | public: |
| 325 | Local_got_entry_key(unsigned int symndx, uint64_t addend) |
| 326 | : symndx_(symndx), addend_(addend) |
| 327 | {} |
| 328 | |
| 329 | // Whether this equals to another Local_got_entry_key. |
| 330 | bool |
| 331 | eq(const Local_got_entry_key& key) const |
| 332 | { |
| 333 | return (this->symndx_ == key.symndx_ && this->addend_ == key.addend_); |
| 334 | } |
| 335 | |
| 336 | // Compute a hash value for this using 64-bit FNV-1a hash. |
| 337 | size_t |
| 338 | hash_value() const |
| 339 | { |
| 340 | uint64_t h = 14695981039346656037ULL; // FNV offset basis. |
| 341 | uint64_t prime = 1099511628211ULL; |
| 342 | h = (h ^ static_cast<uint64_t>(this->symndx_)) * prime; |
| 343 | h = (h ^ static_cast<uint64_t>(this->addend_)) * prime; |
| 344 | return h; |
| 345 | } |
| 346 | |
| 347 | // Functors for associative containers. |
| 348 | struct equal_to |
| 349 | { |
| 350 | bool |
| 351 | operator()(const Local_got_entry_key& key1, |
| 352 | const Local_got_entry_key& key2) const |
| 353 | { return key1.eq(key2); } |
| 354 | }; |
| 355 | |
| 356 | struct hash |
| 357 | { |
| 358 | size_t |
| 359 | operator()(const Local_got_entry_key& key) const |
| 360 | { return key.hash_value(); } |
| 361 | }; |
| 362 | |
| 363 | private: |
| 364 | // The local symbol index. |
| 365 | unsigned int symndx_; |
| 366 | // The addend. |
| 367 | uint64_t addend_; |
| 368 | }; |
| 369 | |
| 370 | // Type for mapping section index to uncompressed size and contents. |
| 371 | |
| 372 | struct Compressed_section_info |
| 373 | { |
| 374 | section_size_type size; |
| 375 | elfcpp::Elf_Xword flag; |
| 376 | uint64_t addralign; |
| 377 | const unsigned char* contents; |
| 378 | }; |
| 379 | typedef std::map<unsigned int, Compressed_section_info> Compressed_section_map; |
| 380 | |
| 381 | template<int size, bool big_endian> |
| 382 | Compressed_section_map* |
| 383 | build_compressed_section_map(const unsigned char* pshdrs, unsigned int shnum, |
| 384 | const char* names, section_size_type names_size, |
| 385 | Object* obj, bool decompress_if_needed); |
| 386 | |
| 387 | // Object is an abstract base class which represents either a 32-bit |
| 388 | // or a 64-bit input object. This can be a regular object file |
| 389 | // (ET_REL) or a shared object (ET_DYN). |
| 390 | |
| 391 | class Object |
| 392 | { |
| 393 | public: |
| 394 | typedef std::vector<Symbol*> Symbols; |
| 395 | |
| 396 | // NAME is the name of the object as we would report it to the user |
| 397 | // (e.g., libfoo.a(bar.o) if this is in an archive. INPUT_FILE is |
| 398 | // used to read the file. OFFSET is the offset within the input |
| 399 | // file--0 for a .o or .so file, something else for a .a file. |
| 400 | Object(const std::string& name, Input_file* input_file, bool is_dynamic, |
| 401 | off_t offset = 0) |
| 402 | : name_(name), input_file_(input_file), offset_(offset), shnum_(-1U), |
| 403 | is_dynamic_(is_dynamic), is_needed_(false), uses_split_stack_(false), |
| 404 | has_no_split_stack_(false), no_export_(false), |
| 405 | is_in_system_directory_(false), as_needed_(false), xindex_(NULL), |
| 406 | compressed_sections_(NULL) |
| 407 | { |
| 408 | if (input_file != NULL) |
| 409 | { |
| 410 | input_file->file().add_object(); |
| 411 | this->is_in_system_directory_ = input_file->is_in_system_directory(); |
| 412 | this->as_needed_ = input_file->options().as_needed(); |
| 413 | } |
| 414 | } |
| 415 | |
| 416 | virtual ~Object() |
| 417 | { |
| 418 | if (this->input_file_ != NULL) |
| 419 | this->input_file_->file().remove_object(); |
| 420 | } |
| 421 | |
| 422 | // Return the name of the object as we would report it to the user. |
| 423 | const std::string& |
| 424 | name() const |
| 425 | { return this->name_; } |
| 426 | |
| 427 | // Get the offset into the file. |
| 428 | off_t |
| 429 | offset() const |
| 430 | { return this->offset_; } |
| 431 | |
| 432 | // Return whether this is a dynamic object. |
| 433 | bool |
| 434 | is_dynamic() const |
| 435 | { return this->is_dynamic_; } |
| 436 | |
| 437 | // Return the word size of the object file. |
| 438 | virtual int elfsize() const = 0; |
| 439 | |
| 440 | // Return TRUE if this is a big-endian object file. |
| 441 | virtual bool is_big_endian() const = 0; |
| 442 | |
| 443 | // Return whether this object is needed--true if it is a dynamic |
| 444 | // object which defines some symbol referenced by a regular object. |
| 445 | // We keep the flag here rather than in Dynobj for convenience when |
| 446 | // setting it. |
| 447 | bool |
| 448 | is_needed() const |
| 449 | { return this->is_needed_; } |
| 450 | |
| 451 | // Record that this object is needed. |
| 452 | void |
| 453 | set_is_needed() |
| 454 | { this->is_needed_ = true; } |
| 455 | |
| 456 | // Return whether this object was compiled with -fsplit-stack. |
| 457 | bool |
| 458 | uses_split_stack() const |
| 459 | { return this->uses_split_stack_; } |
| 460 | |
| 461 | // Return whether this object contains any functions compiled with |
| 462 | // the no_split_stack attribute. |
| 463 | bool |
| 464 | has_no_split_stack() const |
| 465 | { return this->has_no_split_stack_; } |
| 466 | |
| 467 | // Returns NULL for Objects that are not dynamic objects. This method |
| 468 | // is overridden in the Dynobj class. |
| 469 | Dynobj* |
| 470 | dynobj() |
| 471 | { return this->do_dynobj(); } |
| 472 | |
| 473 | // Returns NULL for Objects that are not plugin objects. This method |
| 474 | // is overridden in the Pluginobj class. |
| 475 | Pluginobj* |
| 476 | pluginobj() |
| 477 | { return this->do_pluginobj(); } |
| 478 | |
| 479 | // Get the file. We pass on const-ness. |
| 480 | Input_file* |
| 481 | input_file() |
| 482 | { |
| 483 | gold_assert(this->input_file_ != NULL); |
| 484 | return this->input_file_; |
| 485 | } |
| 486 | |
| 487 | const Input_file* |
| 488 | input_file() const |
| 489 | { |
| 490 | gold_assert(this->input_file_ != NULL); |
| 491 | return this->input_file_; |
| 492 | } |
| 493 | |
| 494 | // Lock the underlying file. |
| 495 | void |
| 496 | lock(const Task* t) |
| 497 | { |
| 498 | if (this->input_file_ != NULL) |
| 499 | this->input_file_->file().lock(t); |
| 500 | } |
| 501 | |
| 502 | // Unlock the underlying file. |
| 503 | void |
| 504 | unlock(const Task* t) |
| 505 | { |
| 506 | if (this->input_file_ != NULL) |
| 507 | this->input_file()->file().unlock(t); |
| 508 | } |
| 509 | |
| 510 | // Return whether the underlying file is locked. |
| 511 | bool |
| 512 | is_locked() const |
| 513 | { return this->input_file_ != NULL && this->input_file_->file().is_locked(); } |
| 514 | |
| 515 | // Return the token, so that the task can be queued. |
| 516 | Task_token* |
| 517 | token() |
| 518 | { |
| 519 | if (this->input_file_ == NULL) |
| 520 | return NULL; |
| 521 | return this->input_file()->file().token(); |
| 522 | } |
| 523 | |
| 524 | // Release the underlying file. |
| 525 | void |
| 526 | release() |
| 527 | { |
| 528 | if (this->input_file_ != NULL) |
| 529 | this->input_file()->file().release(); |
| 530 | } |
| 531 | |
| 532 | // Return whether we should just read symbols from this file. |
| 533 | bool |
| 534 | just_symbols() const |
| 535 | { return this->input_file()->just_symbols(); } |
| 536 | |
| 537 | // Return whether this is an incremental object. |
| 538 | bool |
| 539 | is_incremental() const |
| 540 | { return this->do_is_incremental(); } |
| 541 | |
| 542 | // Return the last modified time of the file. |
| 543 | Timespec |
| 544 | get_mtime() |
| 545 | { return this->do_get_mtime(); } |
| 546 | |
| 547 | // Get the number of sections. |
| 548 | unsigned int |
| 549 | shnum() const |
| 550 | { return this->shnum_; } |
| 551 | |
| 552 | // Return a view of the contents of a section. Set *PLEN to the |
| 553 | // size. CACHE is a hint as in File_read::get_view. |
| 554 | const unsigned char* |
| 555 | section_contents(unsigned int shndx, section_size_type* plen, bool cache); |
| 556 | |
| 557 | // Adjust a symbol's section index as needed. SYMNDX is the index |
| 558 | // of the symbol and SHNDX is the symbol's section from |
| 559 | // get_st_shndx. This returns the section index. It sets |
| 560 | // *IS_ORDINARY to indicate whether this is a normal section index, |
| 561 | // rather than a special code between SHN_LORESERVE and |
| 562 | // SHN_HIRESERVE. |
| 563 | unsigned int |
| 564 | adjust_sym_shndx(unsigned int symndx, unsigned int shndx, bool* is_ordinary) |
| 565 | { |
| 566 | if (shndx < elfcpp::SHN_LORESERVE) |
| 567 | *is_ordinary = true; |
| 568 | else if (shndx == elfcpp::SHN_XINDEX) |
| 569 | { |
| 570 | if (this->xindex_ == NULL) |
| 571 | this->xindex_ = this->do_initialize_xindex(); |
| 572 | shndx = this->xindex_->sym_xindex_to_shndx(this, symndx); |
| 573 | *is_ordinary = true; |
| 574 | } |
| 575 | else |
| 576 | *is_ordinary = false; |
| 577 | return shndx; |
| 578 | } |
| 579 | |
| 580 | // Return the size of a section given a section index. |
| 581 | uint64_t |
| 582 | section_size(unsigned int shndx) |
| 583 | { return this->do_section_size(shndx); } |
| 584 | |
| 585 | // Return the name of a section given a section index. |
| 586 | std::string |
| 587 | section_name(unsigned int shndx) const |
| 588 | { return this->do_section_name(shndx); } |
| 589 | |
| 590 | // Return the section flags given a section index. |
| 591 | uint64_t |
| 592 | section_flags(unsigned int shndx) |
| 593 | { return this->do_section_flags(shndx); } |
| 594 | |
| 595 | // Return the section entsize given a section index. |
| 596 | uint64_t |
| 597 | section_entsize(unsigned int shndx) |
| 598 | { return this->do_section_entsize(shndx); } |
| 599 | |
| 600 | // Return the section address given a section index. |
| 601 | uint64_t |
| 602 | section_address(unsigned int shndx) |
| 603 | { return this->do_section_address(shndx); } |
| 604 | |
| 605 | // Return the section type given a section index. |
| 606 | unsigned int |
| 607 | section_type(unsigned int shndx) |
| 608 | { return this->do_section_type(shndx); } |
| 609 | |
| 610 | // Return the section link field given a section index. |
| 611 | unsigned int |
| 612 | section_link(unsigned int shndx) |
| 613 | { return this->do_section_link(shndx); } |
| 614 | |
| 615 | // Return the section info field given a section index. |
| 616 | unsigned int |
| 617 | section_info(unsigned int shndx) |
| 618 | { return this->do_section_info(shndx); } |
| 619 | |
| 620 | // Return the required section alignment given a section index. |
| 621 | uint64_t |
| 622 | section_addralign(unsigned int shndx) |
| 623 | { return this->do_section_addralign(shndx); } |
| 624 | |
| 625 | // Return the output section given a section index. |
| 626 | Output_section* |
| 627 | output_section(unsigned int shndx) const |
| 628 | { return this->do_output_section(shndx); } |
| 629 | |
| 630 | // Given a section index, return its address. |
| 631 | // The return value will be -1U if the section is specially mapped, |
| 632 | // such as a merge section. |
| 633 | uint64_t |
| 634 | output_section_address(unsigned int shndx) |
| 635 | { return this->do_output_section_address(shndx); } |
| 636 | |
| 637 | // Given a section index, return the offset in the Output_section. |
| 638 | // The return value will be -1U if the section is specially mapped, |
| 639 | // such as a merge section. |
| 640 | uint64_t |
| 641 | output_section_offset(unsigned int shndx) const |
| 642 | { return this->do_output_section_offset(shndx); } |
| 643 | |
| 644 | // Read the symbol information. |
| 645 | void |
| 646 | read_symbols(Read_symbols_data* sd) |
| 647 | { return this->do_read_symbols(sd); } |
| 648 | |
| 649 | // Pass sections which should be included in the link to the Layout |
| 650 | // object, and record where the sections go in the output file. |
| 651 | void |
| 652 | layout(Symbol_table* symtab, Layout* layout, Read_symbols_data* sd) |
| 653 | { this->do_layout(symtab, layout, sd); } |
| 654 | |
| 655 | // Add symbol information to the global symbol table. |
| 656 | void |
| 657 | add_symbols(Symbol_table* symtab, Read_symbols_data* sd, Layout *layout) |
| 658 | { this->do_add_symbols(symtab, sd, layout); } |
| 659 | |
| 660 | // Add symbol information to the global symbol table. |
| 661 | Archive::Should_include |
| 662 | should_include_member(Symbol_table* symtab, Layout* layout, |
| 663 | Read_symbols_data* sd, std::string* why) |
| 664 | { return this->do_should_include_member(symtab, layout, sd, why); } |
| 665 | |
| 666 | // Iterate over global symbols, calling a visitor class V for each. |
| 667 | void |
| 668 | for_all_global_symbols(Read_symbols_data* sd, |
| 669 | Library_base::Symbol_visitor_base* v) |
| 670 | { return this->do_for_all_global_symbols(sd, v); } |
| 671 | |
| 672 | // Iterate over local symbols, calling a visitor class V for each GOT offset |
| 673 | // associated with a local symbol. |
| 674 | void |
| 675 | for_all_local_got_entries(Got_offset_list::Visitor* v) const |
| 676 | { this->do_for_all_local_got_entries(v); } |
| 677 | |
| 678 | // Functions and types for the elfcpp::Elf_file interface. This |
| 679 | // permit us to use Object as the File template parameter for |
| 680 | // elfcpp::Elf_file. |
| 681 | |
| 682 | // The View class is returned by view. It must support a single |
| 683 | // method, data(). This is trivial, because get_view does what we |
| 684 | // need. |
| 685 | class View |
| 686 | { |
| 687 | public: |
| 688 | View(const unsigned char* p) |
| 689 | : p_(p) |
| 690 | { } |
| 691 | |
| 692 | const unsigned char* |
| 693 | data() const |
| 694 | { return this->p_; } |
| 695 | |
| 696 | private: |
| 697 | const unsigned char* p_; |
| 698 | }; |
| 699 | |
| 700 | // Return a View. |
| 701 | View |
| 702 | view(off_t file_offset, section_size_type data_size) |
| 703 | { return View(this->get_view(file_offset, data_size, true, true)); } |
| 704 | |
| 705 | // Report an error. |
| 706 | void |
| 707 | error(const char* format, ...) const ATTRIBUTE_PRINTF_2; |
| 708 | |
| 709 | // A location in the file. |
| 710 | struct Location |
| 711 | { |
| 712 | off_t file_offset; |
| 713 | off_t data_size; |
| 714 | |
| 715 | Location(off_t fo, section_size_type ds) |
| 716 | : file_offset(fo), data_size(ds) |
| 717 | { } |
| 718 | }; |
| 719 | |
| 720 | // Get a View given a Location. |
| 721 | View view(Location loc) |
| 722 | { return View(this->get_view(loc.file_offset, loc.data_size, true, true)); } |
| 723 | |
| 724 | // Get a view into the underlying file. |
| 725 | const unsigned char* |
| 726 | get_view(off_t start, section_size_type size, bool aligned, bool cache) |
| 727 | { |
| 728 | return this->input_file()->file().get_view(this->offset_, start, size, |
| 729 | aligned, cache); |
| 730 | } |
| 731 | |
| 732 | // Get a lasting view into the underlying file. |
| 733 | File_view* |
| 734 | get_lasting_view(off_t start, section_size_type size, bool aligned, |
| 735 | bool cache) |
| 736 | { |
| 737 | return this->input_file()->file().get_lasting_view(this->offset_, start, |
| 738 | size, aligned, cache); |
| 739 | } |
| 740 | |
| 741 | // Read data from the underlying file. |
| 742 | void |
| 743 | read(off_t start, section_size_type size, void* p) |
| 744 | { this->input_file()->file().read(start + this->offset_, size, p); } |
| 745 | |
| 746 | // Read multiple data from the underlying file. |
| 747 | void |
| 748 | read_multiple(const File_read::Read_multiple& rm) |
| 749 | { this->input_file()->file().read_multiple(this->offset_, rm); } |
| 750 | |
| 751 | // Stop caching views in the underlying file. |
| 752 | void |
| 753 | clear_view_cache_marks() |
| 754 | { |
| 755 | if (this->input_file_ != NULL) |
| 756 | this->input_file_->file().clear_view_cache_marks(); |
| 757 | } |
| 758 | |
| 759 | // Get the number of global symbols defined by this object, and the |
| 760 | // number of the symbols whose final definition came from this |
| 761 | // object. |
| 762 | void |
| 763 | get_global_symbol_counts(const Symbol_table* symtab, size_t* defined, |
| 764 | size_t* used) const |
| 765 | { this->do_get_global_symbol_counts(symtab, defined, used); } |
| 766 | |
| 767 | // Get the symbols defined in this object. |
| 768 | const Symbols* |
| 769 | get_global_symbols() const |
| 770 | { return this->do_get_global_symbols(); } |
| 771 | |
| 772 | // Set flag that this object was found in a system directory. |
| 773 | void |
| 774 | set_is_in_system_directory() |
| 775 | { this->is_in_system_directory_ = true; } |
| 776 | |
| 777 | // Return whether this object was found in a system directory. |
| 778 | bool |
| 779 | is_in_system_directory() const |
| 780 | { return this->is_in_system_directory_; } |
| 781 | |
| 782 | // Set flag that this object was linked with --as-needed. |
| 783 | void |
| 784 | set_as_needed() |
| 785 | { this->as_needed_ = true; } |
| 786 | |
| 787 | // Clear flag that this object was linked with --as-needed. |
| 788 | void |
| 789 | clear_as_needed() |
| 790 | { this->as_needed_ = false; } |
| 791 | |
| 792 | // Return whether this object was linked with --as-needed. |
| 793 | bool |
| 794 | as_needed() const |
| 795 | { return this->as_needed_; } |
| 796 | |
| 797 | // Return whether we found this object by searching a directory. |
| 798 | bool |
| 799 | searched_for() const |
| 800 | { return this->input_file()->will_search_for(); } |
| 801 | |
| 802 | bool |
| 803 | no_export() const |
| 804 | { return this->no_export_; } |
| 805 | |
| 806 | void |
| 807 | set_no_export(bool value) |
| 808 | { this->no_export_ = value; } |
| 809 | |
| 810 | bool |
| 811 | section_is_compressed(unsigned int shndx, |
| 812 | section_size_type* uncompressed_size, |
| 813 | elfcpp::Elf_Xword* palign = NULL) const |
| 814 | { |
| 815 | if (this->compressed_sections_ == NULL) |
| 816 | return false; |
| 817 | Compressed_section_map::const_iterator p = |
| 818 | this->compressed_sections_->find(shndx); |
| 819 | if (p != this->compressed_sections_->end()) |
| 820 | { |
| 821 | if (uncompressed_size != NULL) |
| 822 | *uncompressed_size = p->second.size; |
| 823 | if (palign != NULL) |
| 824 | *palign = p->second.addralign; |
| 825 | return true; |
| 826 | } |
| 827 | return false; |
| 828 | } |
| 829 | |
| 830 | // Return a view of the decompressed contents of a section. Set *PLEN |
| 831 | // to the size. Set *IS_NEW to true if the contents need to be freed |
| 832 | // by the caller. |
| 833 | const unsigned char* |
| 834 | decompressed_section_contents(unsigned int shndx, section_size_type* plen, |
| 835 | bool* is_cached, uint64_t* palign = NULL); |
| 836 | |
| 837 | // Discard any buffers of decompressed sections. This is done |
| 838 | // at the end of the Add_symbols task. |
| 839 | void |
| 840 | discard_decompressed_sections(); |
| 841 | |
| 842 | // Return the index of the first incremental relocation for symbol SYMNDX. |
| 843 | unsigned int |
| 844 | get_incremental_reloc_base(unsigned int symndx) const |
| 845 | { return this->do_get_incremental_reloc_base(symndx); } |
| 846 | |
| 847 | // Return the number of incremental relocations for symbol SYMNDX. |
| 848 | unsigned int |
| 849 | get_incremental_reloc_count(unsigned int symndx) const |
| 850 | { return this->do_get_incremental_reloc_count(symndx); } |
| 851 | |
| 852 | // Return the output view for section SHNDX. |
| 853 | unsigned char* |
| 854 | get_output_view(unsigned int shndx, section_size_type* plen) const |
| 855 | { return this->do_get_output_view(shndx, plen); } |
| 856 | |
| 857 | protected: |
| 858 | // Returns NULL for Objects that are not dynamic objects. This method |
| 859 | // is overridden in the Dynobj class. |
| 860 | virtual Dynobj* |
| 861 | do_dynobj() |
| 862 | { return NULL; } |
| 863 | |
| 864 | // Returns NULL for Objects that are not plugin objects. This method |
| 865 | // is overridden in the Pluginobj class. |
| 866 | virtual Pluginobj* |
| 867 | do_pluginobj() |
| 868 | { return NULL; } |
| 869 | |
| 870 | // Return TRUE if this is an incremental (unchanged) input file. |
| 871 | // We return FALSE by default; the incremental object classes |
| 872 | // override this method. |
| 873 | virtual bool |
| 874 | do_is_incremental() const |
| 875 | { return false; } |
| 876 | |
| 877 | // Return the last modified time of the file. This method may be |
| 878 | // overridden for subclasses that don't use an actual file (e.g., |
| 879 | // Incremental objects). |
| 880 | virtual Timespec |
| 881 | do_get_mtime() |
| 882 | { return this->input_file()->file().get_mtime(); } |
| 883 | |
| 884 | // Read the symbols--implemented by child class. |
| 885 | virtual void |
| 886 | do_read_symbols(Read_symbols_data*) = 0; |
| 887 | |
| 888 | // Lay out sections--implemented by child class. |
| 889 | virtual void |
| 890 | do_layout(Symbol_table*, Layout*, Read_symbols_data*) = 0; |
| 891 | |
| 892 | // Add symbol information to the global symbol table--implemented by |
| 893 | // child class. |
| 894 | virtual void |
| 895 | do_add_symbols(Symbol_table*, Read_symbols_data*, Layout*) = 0; |
| 896 | |
| 897 | virtual Archive::Should_include |
| 898 | do_should_include_member(Symbol_table* symtab, Layout*, Read_symbols_data*, |
| 899 | std::string* why) = 0; |
| 900 | |
| 901 | // Iterate over global symbols, calling a visitor class V for each. |
| 902 | virtual void |
| 903 | do_for_all_global_symbols(Read_symbols_data* sd, |
| 904 | Library_base::Symbol_visitor_base* v) = 0; |
| 905 | |
| 906 | // Iterate over local symbols, calling a visitor class V for each GOT offset |
| 907 | // associated with a local symbol. |
| 908 | virtual void |
| 909 | do_for_all_local_got_entries(Got_offset_list::Visitor* v) const = 0; |
| 910 | |
| 911 | // Return the location of the contents of a section. Implemented by |
| 912 | // child class. |
| 913 | virtual const unsigned char* |
| 914 | do_section_contents(unsigned int shndx, section_size_type* plen, |
| 915 | bool cache) = 0; |
| 916 | |
| 917 | // Get the size of a section--implemented by child class. |
| 918 | virtual uint64_t |
| 919 | do_section_size(unsigned int shndx) = 0; |
| 920 | |
| 921 | // Get the name of a section--implemented by child class. |
| 922 | virtual std::string |
| 923 | do_section_name(unsigned int shndx) const = 0; |
| 924 | |
| 925 | // Get section flags--implemented by child class. |
| 926 | virtual uint64_t |
| 927 | do_section_flags(unsigned int shndx) = 0; |
| 928 | |
| 929 | // Get section entsize--implemented by child class. |
| 930 | virtual uint64_t |
| 931 | do_section_entsize(unsigned int shndx) = 0; |
| 932 | |
| 933 | // Get section address--implemented by child class. |
| 934 | virtual uint64_t |
| 935 | do_section_address(unsigned int shndx) = 0; |
| 936 | |
| 937 | // Get section type--implemented by child class. |
| 938 | virtual unsigned int |
| 939 | do_section_type(unsigned int shndx) = 0; |
| 940 | |
| 941 | // Get section link field--implemented by child class. |
| 942 | virtual unsigned int |
| 943 | do_section_link(unsigned int shndx) = 0; |
| 944 | |
| 945 | // Get section info field--implemented by child class. |
| 946 | virtual unsigned int |
| 947 | do_section_info(unsigned int shndx) = 0; |
| 948 | |
| 949 | // Get section alignment--implemented by child class. |
| 950 | virtual uint64_t |
| 951 | do_section_addralign(unsigned int shndx) = 0; |
| 952 | |
| 953 | // Return the output section given a section index--implemented |
| 954 | // by child class. |
| 955 | virtual Output_section* |
| 956 | do_output_section(unsigned int) const |
| 957 | { gold_unreachable(); } |
| 958 | |
| 959 | // Get the address of a section--implemented by child class. |
| 960 | virtual uint64_t |
| 961 | do_output_section_address(unsigned int) |
| 962 | { gold_unreachable(); } |
| 963 | |
| 964 | // Get the offset of a section--implemented by child class. |
| 965 | virtual uint64_t |
| 966 | do_output_section_offset(unsigned int) const |
| 967 | { gold_unreachable(); } |
| 968 | |
| 969 | // Return the Xindex structure to use. |
| 970 | virtual Xindex* |
| 971 | do_initialize_xindex() = 0; |
| 972 | |
| 973 | // Implement get_global_symbol_counts--implemented by child class. |
| 974 | virtual void |
| 975 | do_get_global_symbol_counts(const Symbol_table*, size_t*, size_t*) const = 0; |
| 976 | |
| 977 | virtual const Symbols* |
| 978 | do_get_global_symbols() const = 0; |
| 979 | |
| 980 | // Set the number of sections. |
| 981 | void |
| 982 | set_shnum(int shnum) |
| 983 | { this->shnum_ = shnum; } |
| 984 | |
| 985 | // Functions used by both Sized_relobj_file and Sized_dynobj. |
| 986 | |
| 987 | // Read the section data into a Read_symbols_data object. |
| 988 | template<int size, bool big_endian> |
| 989 | void |
| 990 | read_section_data(elfcpp::Elf_file<size, big_endian, Object>*, |
| 991 | Read_symbols_data*); |
| 992 | |
| 993 | // Find the section header with the given NAME. If HDR is non-NULL |
| 994 | // then it is a section header returned from a previous call to this |
| 995 | // function and the next section header with the same name will be |
| 996 | // returned. |
| 997 | template<int size, bool big_endian> |
| 998 | const unsigned char* |
| 999 | find_shdr(const unsigned char* pshdrs, const char* name, |
| 1000 | const char* names, section_size_type names_size, |
| 1001 | const unsigned char* hdr) const; |
| 1002 | |
| 1003 | // Let the child class initialize the xindex object directly. |
| 1004 | void |
| 1005 | set_xindex(Xindex* xindex) |
| 1006 | { |
| 1007 | gold_assert(this->xindex_ == NULL); |
| 1008 | this->xindex_ = xindex; |
| 1009 | } |
| 1010 | |
| 1011 | // If NAME is the name of a special .gnu.warning section, arrange |
| 1012 | // for the warning to be issued. SHNDX is the section index. |
| 1013 | // Return whether it is a warning section. |
| 1014 | bool |
| 1015 | handle_gnu_warning_section(const char* name, unsigned int shndx, |
| 1016 | Symbol_table*); |
| 1017 | |
| 1018 | // If NAME is the name of the special section which indicates that |
| 1019 | // this object was compiled with -fsplit-stack, mark it accordingly, |
| 1020 | // and return true. Otherwise return false. |
| 1021 | bool |
| 1022 | handle_split_stack_section(const char* name); |
| 1023 | |
| 1024 | // Discard any buffers of decompressed sections. This is done |
| 1025 | // at the end of the Add_symbols task. |
| 1026 | virtual void |
| 1027 | do_discard_decompressed_sections() |
| 1028 | { } |
| 1029 | |
| 1030 | // Return the index of the first incremental relocation for symbol SYMNDX-- |
| 1031 | // implemented by child class. |
| 1032 | virtual unsigned int |
| 1033 | do_get_incremental_reloc_base(unsigned int) const |
| 1034 | { gold_unreachable(); } |
| 1035 | |
| 1036 | // Return the number of incremental relocations for symbol SYMNDX-- |
| 1037 | // implemented by child class. |
| 1038 | virtual unsigned int |
| 1039 | do_get_incremental_reloc_count(unsigned int) const |
| 1040 | { gold_unreachable(); } |
| 1041 | |
| 1042 | // Return the output view for a section. |
| 1043 | virtual unsigned char* |
| 1044 | do_get_output_view(unsigned int, section_size_type*) const |
| 1045 | { gold_unreachable(); } |
| 1046 | |
| 1047 | void |
| 1048 | set_compressed_sections(Compressed_section_map* compressed_sections) |
| 1049 | { this->compressed_sections_ = compressed_sections; } |
| 1050 | |
| 1051 | Compressed_section_map* |
| 1052 | compressed_sections() |
| 1053 | { return this->compressed_sections_; } |
| 1054 | |
| 1055 | private: |
| 1056 | // This class may not be copied. |
| 1057 | Object(const Object&); |
| 1058 | Object& operator=(const Object&); |
| 1059 | |
| 1060 | // Name of object as printed to user. |
| 1061 | std::string name_; |
| 1062 | // For reading the file. |
| 1063 | Input_file* input_file_; |
| 1064 | // Offset within the file--0 for an object file, non-0 for an |
| 1065 | // archive. |
| 1066 | off_t offset_; |
| 1067 | // Number of input sections. |
| 1068 | unsigned int shnum_; |
| 1069 | // Whether this is a dynamic object. |
| 1070 | bool is_dynamic_ : 1; |
| 1071 | // Whether this object is needed. This is only set for dynamic |
| 1072 | // objects, and means that the object defined a symbol which was |
| 1073 | // used by a reference from a regular object. |
| 1074 | bool is_needed_ : 1; |
| 1075 | // Whether this object was compiled with -fsplit-stack. |
| 1076 | bool uses_split_stack_ : 1; |
| 1077 | // Whether this object contains any functions compiled with the |
| 1078 | // no_split_stack attribute. |
| 1079 | bool has_no_split_stack_ : 1; |
| 1080 | // True if exclude this object from automatic symbol export. |
| 1081 | // This is used only for archive objects. |
| 1082 | bool no_export_ : 1; |
| 1083 | // True if the object was found in a system directory. |
| 1084 | bool is_in_system_directory_ : 1; |
| 1085 | // True if the object was linked with --as-needed. |
| 1086 | bool as_needed_ : 1; |
| 1087 | // Many sections for objects with more than SHN_LORESERVE sections. |
| 1088 | Xindex* xindex_; |
| 1089 | // For compressed debug sections, map section index to uncompressed size |
| 1090 | // and contents. |
| 1091 | Compressed_section_map* compressed_sections_; |
| 1092 | }; |
| 1093 | |
| 1094 | // A regular object (ET_REL). This is an abstract base class itself. |
| 1095 | // The implementation is the template class Sized_relobj_file. |
| 1096 | |
| 1097 | class Relobj : public Object |
| 1098 | { |
| 1099 | public: |
| 1100 | Relobj(const std::string& name, Input_file* input_file, off_t offset = 0) |
| 1101 | : Object(name, input_file, false, offset), |
| 1102 | output_sections_(), |
| 1103 | map_to_relocatable_relocs_(NULL), |
| 1104 | object_merge_map_(NULL), |
| 1105 | relocs_must_follow_section_writes_(false), |
| 1106 | sd_(NULL), |
| 1107 | reloc_counts_(NULL), |
| 1108 | reloc_bases_(NULL), |
| 1109 | first_dyn_reloc_(0), |
| 1110 | dyn_reloc_count_(0) |
| 1111 | { } |
| 1112 | |
| 1113 | // During garbage collection, the Read_symbols_data pass for |
| 1114 | // each object is stored as layout needs to be done after |
| 1115 | // reloc processing. |
| 1116 | Symbols_data* |
| 1117 | get_symbols_data() |
| 1118 | { return this->sd_; } |
| 1119 | |
| 1120 | // Decides which section names have to be included in the worklist |
| 1121 | // as roots. |
| 1122 | bool |
| 1123 | is_section_name_included(const char* name); |
| 1124 | |
| 1125 | void |
| 1126 | copy_symbols_data(Symbols_data* gc_sd, Read_symbols_data* sd, |
| 1127 | unsigned int section_header_size); |
| 1128 | |
| 1129 | void |
| 1130 | set_symbols_data(Symbols_data* sd) |
| 1131 | { this->sd_ = sd; } |
| 1132 | |
| 1133 | // During garbage collection, the Read_relocs pass for all objects |
| 1134 | // is done before scanning the relocs. In that case, this->rd_ is |
| 1135 | // used to store the information from Read_relocs for each object. |
| 1136 | // This data is also used to compute the list of relevant sections. |
| 1137 | Read_relocs_data* |
| 1138 | get_relocs_data() |
| 1139 | { return this->rd_; } |
| 1140 | |
| 1141 | void |
| 1142 | set_relocs_data(Read_relocs_data* rd) |
| 1143 | { this->rd_ = rd; } |
| 1144 | |
| 1145 | virtual bool |
| 1146 | is_output_section_offset_invalid(unsigned int shndx) const = 0; |
| 1147 | |
| 1148 | // Read the relocs. |
| 1149 | void |
| 1150 | read_relocs(Read_relocs_data* rd) |
| 1151 | { return this->do_read_relocs(rd); } |
| 1152 | |
| 1153 | // Process the relocs, during garbage collection only. |
| 1154 | void |
| 1155 | gc_process_relocs(Symbol_table* symtab, Layout* layout, Read_relocs_data* rd) |
| 1156 | { return this->do_gc_process_relocs(symtab, layout, rd); } |
| 1157 | |
| 1158 | // Scan the relocs and adjust the symbol table. |
| 1159 | void |
| 1160 | scan_relocs(Symbol_table* symtab, Layout* layout, Read_relocs_data* rd) |
| 1161 | { return this->do_scan_relocs(symtab, layout, rd); } |
| 1162 | |
| 1163 | // Return the value of the local symbol whose index is SYMNDX, plus |
| 1164 | // ADDEND. ADDEND is passed in so that we can correctly handle the |
| 1165 | // section symbol for a merge section. |
| 1166 | uint64_t |
| 1167 | local_symbol_value(unsigned int symndx, uint64_t addend) const |
| 1168 | { return this->do_local_symbol_value(symndx, addend); } |
| 1169 | |
| 1170 | // Return the PLT offset for a local symbol. It is an error to call |
| 1171 | // this if it doesn't have one. |
| 1172 | unsigned int |
| 1173 | local_plt_offset(unsigned int symndx) const |
| 1174 | { return this->do_local_plt_offset(symndx); } |
| 1175 | |
| 1176 | // Return whether the local symbol SYMNDX has a GOT offset of type |
| 1177 | // GOT_TYPE. |
| 1178 | bool |
| 1179 | local_has_got_offset(unsigned int symndx, unsigned int got_type) const |
| 1180 | { return this->do_local_has_got_offset(symndx, got_type, 0); } |
| 1181 | |
| 1182 | // Return whether the local symbol SYMNDX plus ADDEND has a GOT offset |
| 1183 | // of type GOT_TYPE. |
| 1184 | bool |
| 1185 | local_has_got_offset(unsigned int symndx, unsigned int got_type, |
| 1186 | uint64_t addend) const |
| 1187 | { return this->do_local_has_got_offset(symndx, got_type, addend); } |
| 1188 | |
| 1189 | // Return the GOT offset of type GOT_TYPE of the local symbol |
| 1190 | // SYMNDX. It is an error to call this if the symbol does not have |
| 1191 | // a GOT offset of the specified type. |
| 1192 | unsigned int |
| 1193 | local_got_offset(unsigned int symndx, unsigned int got_type) const |
| 1194 | { return this->do_local_got_offset(symndx, got_type, 0); } |
| 1195 | |
| 1196 | // Return the GOT offset of type GOT_TYPE of the local symbol |
| 1197 | // SYMNDX plus ADDEND. It is an error to call this if the symbol |
| 1198 | // does not have a GOT offset of the specified type. |
| 1199 | unsigned int |
| 1200 | local_got_offset(unsigned int symndx, unsigned int got_type, |
| 1201 | uint64_t addend) const |
| 1202 | { return this->do_local_got_offset(symndx, got_type, addend); } |
| 1203 | |
| 1204 | // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX |
| 1205 | // to GOT_OFFSET. |
| 1206 | void |
| 1207 | set_local_got_offset(unsigned int symndx, unsigned int got_type, |
| 1208 | unsigned int got_offset) |
| 1209 | { this->do_set_local_got_offset(symndx, got_type, got_offset, 0); } |
| 1210 | |
| 1211 | // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX |
| 1212 | // plus ADDEND to GOT_OFFSET. |
| 1213 | void |
| 1214 | set_local_got_offset(unsigned int symndx, unsigned int got_type, |
| 1215 | unsigned int got_offset, uint64_t addend) |
| 1216 | { this->do_set_local_got_offset(symndx, got_type, got_offset, addend); } |
| 1217 | |
| 1218 | // Return whether the local symbol SYMNDX is a TLS symbol. |
| 1219 | bool |
| 1220 | local_is_tls(unsigned int symndx) const |
| 1221 | { return this->do_local_is_tls(symndx); } |
| 1222 | |
| 1223 | // The number of local symbols in the input symbol table. |
| 1224 | virtual unsigned int |
| 1225 | local_symbol_count() const |
| 1226 | { return this->do_local_symbol_count(); } |
| 1227 | |
| 1228 | // The number of local symbols in the output symbol table. |
| 1229 | virtual unsigned int |
| 1230 | output_local_symbol_count() const |
| 1231 | { return this->do_output_local_symbol_count(); } |
| 1232 | |
| 1233 | // The file offset for local symbols in the output symbol table. |
| 1234 | virtual off_t |
| 1235 | local_symbol_offset() const |
| 1236 | { return this->do_local_symbol_offset(); } |
| 1237 | |
| 1238 | // Initial local symbol processing: count the number of local symbols |
| 1239 | // in the output symbol table and dynamic symbol table; add local symbol |
| 1240 | // names to *POOL and *DYNPOOL. |
| 1241 | void |
| 1242 | count_local_symbols(Stringpool_template<char>* pool, |
| 1243 | Stringpool_template<char>* dynpool) |
| 1244 | { return this->do_count_local_symbols(pool, dynpool); } |
| 1245 | |
| 1246 | // Set the values of the local symbols, set the output symbol table |
| 1247 | // indexes for the local variables, and set the offset where local |
| 1248 | // symbol information will be stored. Returns the new local symbol index. |
| 1249 | unsigned int |
| 1250 | finalize_local_symbols(unsigned int index, off_t off, Symbol_table* symtab) |
| 1251 | { return this->do_finalize_local_symbols(index, off, symtab); } |
| 1252 | |
| 1253 | // Set the output dynamic symbol table indexes for the local variables. |
| 1254 | unsigned int |
| 1255 | set_local_dynsym_indexes(unsigned int index) |
| 1256 | { return this->do_set_local_dynsym_indexes(index); } |
| 1257 | |
| 1258 | // Set the offset where local dynamic symbol information will be stored. |
| 1259 | unsigned int |
| 1260 | set_local_dynsym_offset(off_t off) |
| 1261 | { return this->do_set_local_dynsym_offset(off); } |
| 1262 | |
| 1263 | // Record a dynamic relocation against an input section from this object. |
| 1264 | void |
| 1265 | add_dyn_reloc(unsigned int index) |
| 1266 | { |
| 1267 | if (this->dyn_reloc_count_ == 0) |
| 1268 | this->first_dyn_reloc_ = index; |
| 1269 | ++this->dyn_reloc_count_; |
| 1270 | } |
| 1271 | |
| 1272 | // Return the index of the first dynamic relocation. |
| 1273 | unsigned int |
| 1274 | first_dyn_reloc() const |
| 1275 | { return this->first_dyn_reloc_; } |
| 1276 | |
| 1277 | // Return the count of dynamic relocations. |
| 1278 | unsigned int |
| 1279 | dyn_reloc_count() const |
| 1280 | { return this->dyn_reloc_count_; } |
| 1281 | |
| 1282 | // Relocate the input sections and write out the local symbols. |
| 1283 | void |
| 1284 | relocate(const Symbol_table* symtab, const Layout* layout, Output_file* of) |
| 1285 | { return this->do_relocate(symtab, layout, of); } |
| 1286 | |
| 1287 | // Return whether an input section is being included in the link. |
| 1288 | bool |
| 1289 | is_section_included(unsigned int shndx) const |
| 1290 | { |
| 1291 | gold_assert(shndx < this->output_sections_.size()); |
| 1292 | return this->output_sections_[shndx] != NULL; |
| 1293 | } |
| 1294 | |
| 1295 | // The output section of the input section with index SHNDX. |
| 1296 | // This is only used currently to remove a section from the link in |
| 1297 | // relaxation. |
| 1298 | void |
| 1299 | set_output_section(unsigned int shndx, Output_section* os) |
| 1300 | { |
| 1301 | gold_assert(shndx < this->output_sections_.size()); |
| 1302 | this->output_sections_[shndx] = os; |
| 1303 | } |
| 1304 | |
| 1305 | // Set the offset of an input section within its output section. |
| 1306 | void |
| 1307 | set_section_offset(unsigned int shndx, uint64_t off) |
| 1308 | { this->do_set_section_offset(shndx, off); } |
| 1309 | |
| 1310 | // Return true if we need to wait for output sections to be written |
| 1311 | // before we can apply relocations. This is true if the object has |
| 1312 | // any relocations for sections which require special handling, such |
| 1313 | // as the exception frame section. |
| 1314 | bool |
| 1315 | relocs_must_follow_section_writes() const |
| 1316 | { return this->relocs_must_follow_section_writes_; } |
| 1317 | |
| 1318 | Object_merge_map* |
| 1319 | get_or_create_merge_map(); |
| 1320 | |
| 1321 | template<int size> |
| 1322 | void |
| 1323 | initialize_input_to_output_map(unsigned int shndx, |
| 1324 | typename elfcpp::Elf_types<size>::Elf_Addr starting_address, |
| 1325 | Unordered_map<section_offset_type, |
| 1326 | typename elfcpp::Elf_types<size>::Elf_Addr>* output_address) const; |
| 1327 | |
| 1328 | void |
| 1329 | add_merge_mapping(Output_section_data *output_data, |
| 1330 | unsigned int shndx, section_offset_type offset, |
| 1331 | section_size_type length, |
| 1332 | section_offset_type output_offset); |
| 1333 | |
| 1334 | bool |
| 1335 | merge_output_offset(unsigned int shndx, section_offset_type offset, |
| 1336 | section_offset_type *poutput) const; |
| 1337 | |
| 1338 | const Output_section_data* |
| 1339 | find_merge_section(unsigned int shndx) const; |
| 1340 | |
| 1341 | // Record the relocatable reloc info for an input reloc section. |
| 1342 | void |
| 1343 | set_relocatable_relocs(unsigned int reloc_shndx, Relocatable_relocs* rr) |
| 1344 | { |
| 1345 | gold_assert(reloc_shndx < this->shnum()); |
| 1346 | (*this->map_to_relocatable_relocs_)[reloc_shndx] = rr; |
| 1347 | } |
| 1348 | |
| 1349 | // Get the relocatable reloc info for an input reloc section. |
| 1350 | Relocatable_relocs* |
| 1351 | relocatable_relocs(unsigned int reloc_shndx) |
| 1352 | { |
| 1353 | gold_assert(reloc_shndx < this->shnum()); |
| 1354 | return (*this->map_to_relocatable_relocs_)[reloc_shndx]; |
| 1355 | } |
| 1356 | |
| 1357 | // Layout sections whose layout was deferred while waiting for |
| 1358 | // input files from a plugin. |
| 1359 | void |
| 1360 | layout_deferred_sections(Layout* layout) |
| 1361 | { this->do_layout_deferred_sections(layout); } |
| 1362 | |
| 1363 | // Return the index of the first incremental relocation for symbol SYMNDX. |
| 1364 | virtual unsigned int |
| 1365 | do_get_incremental_reloc_base(unsigned int symndx) const |
| 1366 | { return this->reloc_bases_[symndx]; } |
| 1367 | |
| 1368 | // Return the number of incremental relocations for symbol SYMNDX. |
| 1369 | virtual unsigned int |
| 1370 | do_get_incremental_reloc_count(unsigned int symndx) const |
| 1371 | { return this->reloc_counts_[symndx]; } |
| 1372 | |
| 1373 | // Return the word size of the object file. |
| 1374 | int |
| 1375 | elfsize() const |
| 1376 | { return this->do_elfsize(); } |
| 1377 | |
| 1378 | // Return TRUE if this is a big-endian object file. |
| 1379 | bool |
| 1380 | is_big_endian() const |
| 1381 | { return this->do_is_big_endian(); } |
| 1382 | |
| 1383 | protected: |
| 1384 | // The output section to be used for each input section, indexed by |
| 1385 | // the input section number. The output section is NULL if the |
| 1386 | // input section is to be discarded. |
| 1387 | typedef std::vector<Output_section*> Output_sections; |
| 1388 | |
| 1389 | // Read the relocs--implemented by child class. |
| 1390 | virtual void |
| 1391 | do_read_relocs(Read_relocs_data*) = 0; |
| 1392 | |
| 1393 | // Process the relocs--implemented by child class. |
| 1394 | virtual void |
| 1395 | do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*) = 0; |
| 1396 | |
| 1397 | // Scan the relocs--implemented by child class. |
| 1398 | virtual void |
| 1399 | do_scan_relocs(Symbol_table*, Layout*, Read_relocs_data*) = 0; |
| 1400 | |
| 1401 | // Return the value of a local symbol. |
| 1402 | virtual uint64_t |
| 1403 | do_local_symbol_value(unsigned int symndx, uint64_t addend) const = 0; |
| 1404 | |
| 1405 | // Return the PLT offset of a local symbol. |
| 1406 | virtual unsigned int |
| 1407 | do_local_plt_offset(unsigned int symndx) const = 0; |
| 1408 | |
| 1409 | // Return whether a local symbol plus addend has a GOT offset |
| 1410 | // of a given type. |
| 1411 | virtual bool |
| 1412 | do_local_has_got_offset(unsigned int symndx, |
| 1413 | unsigned int got_type, uint64_t addend) const = 0; |
| 1414 | |
| 1415 | // Return the GOT offset of a given type of a local symbol plus addend. |
| 1416 | virtual unsigned int |
| 1417 | do_local_got_offset(unsigned int symndx, unsigned int got_type, |
| 1418 | uint64_t addend) const = 0; |
| 1419 | |
| 1420 | // Set the GOT offset with a given type for a local symbol plus addend. |
| 1421 | virtual void |
| 1422 | do_set_local_got_offset(unsigned int symndx, unsigned int got_type, |
| 1423 | unsigned int got_offset, uint64_t addend) = 0; |
| 1424 | |
| 1425 | // Return whether local symbol SYMNDX is a TLS symbol. |
| 1426 | virtual bool |
| 1427 | do_local_is_tls(unsigned int symndx) const = 0; |
| 1428 | |
| 1429 | // Return the number of local symbols--implemented by child class. |
| 1430 | virtual unsigned int |
| 1431 | do_local_symbol_count() const = 0; |
| 1432 | |
| 1433 | // Return the number of output local symbols--implemented by child class. |
| 1434 | virtual unsigned int |
| 1435 | do_output_local_symbol_count() const = 0; |
| 1436 | |
| 1437 | // Return the file offset for local symbols--implemented by child class. |
| 1438 | virtual off_t |
| 1439 | do_local_symbol_offset() const = 0; |
| 1440 | |
| 1441 | // Count local symbols--implemented by child class. |
| 1442 | virtual void |
| 1443 | do_count_local_symbols(Stringpool_template<char>*, |
| 1444 | Stringpool_template<char>*) = 0; |
| 1445 | |
| 1446 | // Finalize the local symbols. Set the output symbol table indexes |
| 1447 | // for the local variables, and set the offset where local symbol |
| 1448 | // information will be stored. |
| 1449 | virtual unsigned int |
| 1450 | do_finalize_local_symbols(unsigned int, off_t, Symbol_table*) = 0; |
| 1451 | |
| 1452 | // Set the output dynamic symbol table indexes for the local variables. |
| 1453 | virtual unsigned int |
| 1454 | do_set_local_dynsym_indexes(unsigned int) = 0; |
| 1455 | |
| 1456 | // Set the offset where local dynamic symbol information will be stored. |
| 1457 | virtual unsigned int |
| 1458 | do_set_local_dynsym_offset(off_t) = 0; |
| 1459 | |
| 1460 | // Relocate the input sections and write out the local |
| 1461 | // symbols--implemented by child class. |
| 1462 | virtual void |
| 1463 | do_relocate(const Symbol_table* symtab, const Layout*, Output_file* of) = 0; |
| 1464 | |
| 1465 | // Set the offset of a section--implemented by child class. |
| 1466 | virtual void |
| 1467 | do_set_section_offset(unsigned int shndx, uint64_t off) = 0; |
| 1468 | |
| 1469 | // Layout sections whose layout was deferred while waiting for |
| 1470 | // input files from a plugin--implemented by child class. |
| 1471 | virtual void |
| 1472 | do_layout_deferred_sections(Layout*) = 0; |
| 1473 | |
| 1474 | // Given a section index, return the corresponding Output_section. |
| 1475 | // The return value will be NULL if the section is not included in |
| 1476 | // the link. |
| 1477 | Output_section* |
| 1478 | do_output_section(unsigned int shndx) const |
| 1479 | { |
| 1480 | gold_assert(shndx < this->output_sections_.size()); |
| 1481 | return this->output_sections_[shndx]; |
| 1482 | } |
| 1483 | |
| 1484 | // Return the vector mapping input sections to output sections. |
| 1485 | Output_sections& |
| 1486 | output_sections() |
| 1487 | { return this->output_sections_; } |
| 1488 | |
| 1489 | const Output_sections& |
| 1490 | output_sections() const |
| 1491 | { return this->output_sections_; } |
| 1492 | |
| 1493 | // Set the size of the relocatable relocs array. |
| 1494 | void |
| 1495 | size_relocatable_relocs() |
| 1496 | { |
| 1497 | this->map_to_relocatable_relocs_ = |
| 1498 | new std::vector<Relocatable_relocs*>(this->shnum()); |
| 1499 | } |
| 1500 | |
| 1501 | // Record that we must wait for the output sections to be written |
| 1502 | // before applying relocations. |
| 1503 | void |
| 1504 | set_relocs_must_follow_section_writes() |
| 1505 | { this->relocs_must_follow_section_writes_ = true; } |
| 1506 | |
| 1507 | // Allocate the array for counting incremental relocations. |
| 1508 | void |
| 1509 | allocate_incremental_reloc_counts() |
| 1510 | { |
| 1511 | unsigned int nsyms = this->do_get_global_symbols()->size(); |
| 1512 | this->reloc_counts_ = new unsigned int[nsyms]; |
| 1513 | gold_assert(this->reloc_counts_ != NULL); |
| 1514 | memset(this->reloc_counts_, 0, nsyms * sizeof(unsigned int)); |
| 1515 | } |
| 1516 | |
| 1517 | // Record a relocation in this object referencing global symbol SYMNDX. |
| 1518 | // Used for tracking incremental link information. |
| 1519 | void |
| 1520 | count_incremental_reloc(unsigned int symndx) |
| 1521 | { |
| 1522 | unsigned int nsyms = this->do_get_global_symbols()->size(); |
| 1523 | gold_assert(symndx < nsyms); |
| 1524 | gold_assert(this->reloc_counts_ != NULL); |
| 1525 | ++this->reloc_counts_[symndx]; |
| 1526 | } |
| 1527 | |
| 1528 | // Finalize the incremental relocation information. |
| 1529 | void |
| 1530 | finalize_incremental_relocs(Layout* layout, bool clear_counts); |
| 1531 | |
| 1532 | // Return the index of the next relocation to be written for global symbol |
| 1533 | // SYMNDX. Only valid after finalize_incremental_relocs() has been called. |
| 1534 | unsigned int |
| 1535 | next_incremental_reloc_index(unsigned int symndx) |
| 1536 | { |
| 1537 | unsigned int nsyms = this->do_get_global_symbols()->size(); |
| 1538 | |
| 1539 | gold_assert(this->reloc_counts_ != NULL); |
| 1540 | gold_assert(this->reloc_bases_ != NULL); |
| 1541 | gold_assert(symndx < nsyms); |
| 1542 | |
| 1543 | unsigned int counter = this->reloc_counts_[symndx]++; |
| 1544 | return this->reloc_bases_[symndx] + counter; |
| 1545 | } |
| 1546 | |
| 1547 | // Return the word size of the object file-- |
| 1548 | // implemented by child class. |
| 1549 | virtual int |
| 1550 | do_elfsize() const = 0; |
| 1551 | |
| 1552 | // Return TRUE if this is a big-endian object file-- |
| 1553 | // implemented by child class. |
| 1554 | virtual bool |
| 1555 | do_is_big_endian() const = 0; |
| 1556 | |
| 1557 | private: |
| 1558 | // Mapping from input sections to output section. |
| 1559 | Output_sections output_sections_; |
| 1560 | // Mapping from input section index to the information recorded for |
| 1561 | // the relocations. This is only used for a relocatable link. |
| 1562 | std::vector<Relocatable_relocs*>* map_to_relocatable_relocs_; |
| 1563 | // Mappings for merge sections. This is managed by the code in the |
| 1564 | // Merge_map class. |
| 1565 | Object_merge_map* object_merge_map_; |
| 1566 | // Whether we need to wait for output sections to be written before |
| 1567 | // we can apply relocations. |
| 1568 | bool relocs_must_follow_section_writes_; |
| 1569 | // Used to store the relocs data computed by the Read_relocs pass. |
| 1570 | // Used during garbage collection of unused sections. |
| 1571 | Read_relocs_data* rd_; |
| 1572 | // Used to store the symbols data computed by the Read_symbols pass. |
| 1573 | // Again used during garbage collection when laying out referenced |
| 1574 | // sections. |
| 1575 | gold::Symbols_data* sd_; |
| 1576 | // Per-symbol counts of relocations, for incremental links. |
| 1577 | unsigned int* reloc_counts_; |
| 1578 | // Per-symbol base indexes of relocations, for incremental links. |
| 1579 | unsigned int* reloc_bases_; |
| 1580 | // Index of the first dynamic relocation for this object. |
| 1581 | unsigned int first_dyn_reloc_; |
| 1582 | // Count of dynamic relocations for this object. |
| 1583 | unsigned int dyn_reloc_count_; |
| 1584 | }; |
| 1585 | |
| 1586 | // This class is used to handle relocations against a section symbol |
| 1587 | // in an SHF_MERGE section. For such a symbol, we need to know the |
| 1588 | // addend of the relocation before we can determine the final value. |
| 1589 | // The addend gives us the location in the input section, and we can |
| 1590 | // determine how it is mapped to the output section. For a |
| 1591 | // non-section symbol, we apply the addend to the final value of the |
| 1592 | // symbol; that is done in finalize_local_symbols, and does not use |
| 1593 | // this class. |
| 1594 | |
| 1595 | template<int size> |
| 1596 | class Merged_symbol_value |
| 1597 | { |
| 1598 | public: |
| 1599 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Value; |
| 1600 | |
| 1601 | // We use a hash table to map offsets in the input section to output |
| 1602 | // addresses. |
| 1603 | typedef Unordered_map<section_offset_type, Value> Output_addresses; |
| 1604 | |
| 1605 | Merged_symbol_value(Value input_value, Value output_start_address) |
| 1606 | : input_value_(input_value), output_start_address_(output_start_address), |
| 1607 | output_addresses_() |
| 1608 | { } |
| 1609 | |
| 1610 | // Initialize the hash table. |
| 1611 | void |
| 1612 | initialize_input_to_output_map(const Relobj*, unsigned int input_shndx); |
| 1613 | |
| 1614 | // Release the hash table to save space. |
| 1615 | void |
| 1616 | free_input_to_output_map() |
| 1617 | { this->output_addresses_.clear(); } |
| 1618 | |
| 1619 | // Get the output value corresponding to an addend. The object and |
| 1620 | // input section index are passed in because the caller will have |
| 1621 | // them; otherwise we could store them here. |
| 1622 | Value |
| 1623 | value(const Relobj* object, unsigned int input_shndx, Value addend) const |
| 1624 | { |
| 1625 | // This is a relocation against a section symbol. ADDEND is the |
| 1626 | // offset in the section. The result should be the start of some |
| 1627 | // merge area. If the object file wants something else, it should |
| 1628 | // use a regular symbol rather than a section symbol. |
| 1629 | // Unfortunately, PR 6658 shows a case in which the object file |
| 1630 | // refers to the section symbol, but uses a negative ADDEND to |
| 1631 | // compensate for a PC relative reloc. We can't handle the |
| 1632 | // general case. However, we can handle the special case of a |
| 1633 | // negative addend, by assuming that it refers to the start of the |
| 1634 | // section. Of course, that means that we have to guess when |
| 1635 | // ADDEND is negative. It is normal to see a 32-bit value here |
| 1636 | // even when the template parameter size is 64, as 64-bit object |
| 1637 | // file formats have 32-bit relocations. We know this is a merge |
| 1638 | // section, so we know it has to fit into memory. So we assume |
| 1639 | // that we won't see a value larger than a large 32-bit unsigned |
| 1640 | // value. This will break objects with very very large merge |
| 1641 | // sections; they probably break in other ways anyhow. |
| 1642 | Value input_offset = this->input_value_; |
| 1643 | if (addend < 0xffffff00) |
| 1644 | { |
| 1645 | input_offset += addend; |
| 1646 | addend = 0; |
| 1647 | } |
| 1648 | typename Output_addresses::const_iterator p = |
| 1649 | this->output_addresses_.find(input_offset); |
| 1650 | if (p != this->output_addresses_.end()) |
| 1651 | return p->second + addend; |
| 1652 | |
| 1653 | return (this->value_from_output_section(object, input_shndx, input_offset) |
| 1654 | + addend); |
| 1655 | } |
| 1656 | |
| 1657 | private: |
| 1658 | // Get the output value for an input offset if we couldn't find it |
| 1659 | // in the hash table. |
| 1660 | Value |
| 1661 | value_from_output_section(const Relobj*, unsigned int input_shndx, |
| 1662 | Value input_offset) const; |
| 1663 | |
| 1664 | // The value of the section symbol in the input file. This is |
| 1665 | // normally zero, but could in principle be something else. |
| 1666 | Value input_value_; |
| 1667 | // The start address of this merged section in the output file. |
| 1668 | Value output_start_address_; |
| 1669 | // A hash table which maps offsets in the input section to output |
| 1670 | // addresses. This only maps specific offsets, not all offsets. |
| 1671 | Output_addresses output_addresses_; |
| 1672 | }; |
| 1673 | |
| 1674 | // This POD class is holds the value of a symbol. This is used for |
| 1675 | // local symbols, and for all symbols during relocation processing. |
| 1676 | // For special sections, such as SHF_MERGE sections, this calls a |
| 1677 | // function to get the final symbol value. |
| 1678 | |
| 1679 | template<int size> |
| 1680 | class Symbol_value |
| 1681 | { |
| 1682 | public: |
| 1683 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Value; |
| 1684 | |
| 1685 | Symbol_value() |
| 1686 | : output_symtab_index_(0), output_dynsym_index_(-1U), input_shndx_(0), |
| 1687 | is_ordinary_shndx_(false), is_section_symbol_(false), |
| 1688 | is_tls_symbol_(false), is_ifunc_symbol_(false), has_output_value_(true) |
| 1689 | { this->u_.value = 0; } |
| 1690 | |
| 1691 | ~Symbol_value() |
| 1692 | { |
| 1693 | if (!this->has_output_value_) |
| 1694 | delete this->u_.merged_symbol_value; |
| 1695 | } |
| 1696 | |
| 1697 | // Get the value of this symbol. OBJECT is the object in which this |
| 1698 | // symbol is defined, and ADDEND is an addend to add to the value. |
| 1699 | template<bool big_endian> |
| 1700 | Value |
| 1701 | value(const Sized_relobj_file<size, big_endian>* object, Value addend) const |
| 1702 | { |
| 1703 | if (this->has_output_value_) |
| 1704 | return this->u_.value + addend; |
| 1705 | else |
| 1706 | { |
| 1707 | gold_assert(this->is_ordinary_shndx_); |
| 1708 | return this->u_.merged_symbol_value->value(object, this->input_shndx_, |
| 1709 | addend); |
| 1710 | } |
| 1711 | } |
| 1712 | |
| 1713 | // Set the value of this symbol in the output symbol table. |
| 1714 | void |
| 1715 | set_output_value(Value value) |
| 1716 | { this->u_.value = value; } |
| 1717 | |
| 1718 | // For a section symbol in a merged section, we need more |
| 1719 | // information. |
| 1720 | void |
| 1721 | set_merged_symbol_value(Merged_symbol_value<size>* msv) |
| 1722 | { |
| 1723 | gold_assert(this->is_section_symbol_); |
| 1724 | this->has_output_value_ = false; |
| 1725 | this->u_.merged_symbol_value = msv; |
| 1726 | } |
| 1727 | |
| 1728 | // Initialize the input to output map for a section symbol in a |
| 1729 | // merged section. We also initialize the value of a non-section |
| 1730 | // symbol in a merged section. |
| 1731 | void |
| 1732 | initialize_input_to_output_map(const Relobj* object) |
| 1733 | { |
| 1734 | if (!this->has_output_value_) |
| 1735 | { |
| 1736 | gold_assert(this->is_section_symbol_ && this->is_ordinary_shndx_); |
| 1737 | Merged_symbol_value<size>* msv = this->u_.merged_symbol_value; |
| 1738 | msv->initialize_input_to_output_map(object, this->input_shndx_); |
| 1739 | } |
| 1740 | } |
| 1741 | |
| 1742 | // Free the input to output map for a section symbol in a merged |
| 1743 | // section. |
| 1744 | void |
| 1745 | free_input_to_output_map() |
| 1746 | { |
| 1747 | if (!this->has_output_value_) |
| 1748 | this->u_.merged_symbol_value->free_input_to_output_map(); |
| 1749 | } |
| 1750 | |
| 1751 | // Set the value of the symbol from the input file. This is only |
| 1752 | // called by count_local_symbols, to communicate the value to |
| 1753 | // finalize_local_symbols. |
| 1754 | void |
| 1755 | set_input_value(Value value) |
| 1756 | { this->u_.value = value; } |
| 1757 | |
| 1758 | // Return the input value. This is only called by |
| 1759 | // finalize_local_symbols and (in special cases) relocate_section. |
| 1760 | Value |
| 1761 | input_value() const |
| 1762 | { return this->u_.value; } |
| 1763 | |
| 1764 | // Return whether we have set the index in the output symbol table |
| 1765 | // yet. |
| 1766 | bool |
| 1767 | is_output_symtab_index_set() const |
| 1768 | { |
| 1769 | return (this->output_symtab_index_ != 0 |
| 1770 | && this->output_symtab_index_ != -2U); |
| 1771 | } |
| 1772 | |
| 1773 | // Return whether this symbol may be discarded from the normal |
| 1774 | // symbol table. |
| 1775 | bool |
| 1776 | may_be_discarded_from_output_symtab() const |
| 1777 | { |
| 1778 | gold_assert(!this->is_output_symtab_index_set()); |
| 1779 | return this->output_symtab_index_ != -2U; |
| 1780 | } |
| 1781 | |
| 1782 | // Return whether this symbol has an entry in the output symbol |
| 1783 | // table. |
| 1784 | bool |
| 1785 | has_output_symtab_entry() const |
| 1786 | { |
| 1787 | gold_assert(this->is_output_symtab_index_set()); |
| 1788 | return this->output_symtab_index_ != -1U; |
| 1789 | } |
| 1790 | |
| 1791 | // Return the index in the output symbol table. |
| 1792 | unsigned int |
| 1793 | output_symtab_index() const |
| 1794 | { |
| 1795 | gold_assert(this->is_output_symtab_index_set() |
| 1796 | && this->output_symtab_index_ != -1U); |
| 1797 | return this->output_symtab_index_; |
| 1798 | } |
| 1799 | |
| 1800 | // Set the index in the output symbol table. |
| 1801 | void |
| 1802 | set_output_symtab_index(unsigned int i) |
| 1803 | { |
| 1804 | gold_assert(!this->is_output_symtab_index_set()); |
| 1805 | gold_assert(i != 0 && i != -1U && i != -2U); |
| 1806 | this->output_symtab_index_ = i; |
| 1807 | } |
| 1808 | |
| 1809 | // Record that this symbol should not go into the output symbol |
| 1810 | // table. |
| 1811 | void |
| 1812 | set_no_output_symtab_entry() |
| 1813 | { |
| 1814 | gold_assert(this->output_symtab_index_ == 0); |
| 1815 | this->output_symtab_index_ = -1U; |
| 1816 | } |
| 1817 | |
| 1818 | // Record that this symbol must go into the output symbol table, |
| 1819 | // because it there is a relocation that uses it. |
| 1820 | void |
| 1821 | set_must_have_output_symtab_entry() |
| 1822 | { |
| 1823 | gold_assert(!this->is_output_symtab_index_set()); |
| 1824 | this->output_symtab_index_ = -2U; |
| 1825 | } |
| 1826 | |
| 1827 | // Set the index in the output dynamic symbol table. |
| 1828 | void |
| 1829 | set_needs_output_dynsym_entry() |
| 1830 | { |
| 1831 | gold_assert(!this->is_section_symbol()); |
| 1832 | this->output_dynsym_index_ = 0; |
| 1833 | } |
| 1834 | |
| 1835 | // Return whether this symbol should go into the dynamic symbol |
| 1836 | // table. |
| 1837 | bool |
| 1838 | needs_output_dynsym_entry() const |
| 1839 | { |
| 1840 | return this->output_dynsym_index_ != -1U; |
| 1841 | } |
| 1842 | |
| 1843 | // Return whether this symbol has an entry in the dynamic symbol |
| 1844 | // table. |
| 1845 | bool |
| 1846 | has_output_dynsym_entry() const |
| 1847 | { |
| 1848 | gold_assert(this->output_dynsym_index_ != 0); |
| 1849 | return this->output_dynsym_index_ != -1U; |
| 1850 | } |
| 1851 | |
| 1852 | // Record that this symbol should go into the dynamic symbol table. |
| 1853 | void |
| 1854 | set_output_dynsym_index(unsigned int i) |
| 1855 | { |
| 1856 | gold_assert(this->output_dynsym_index_ == 0); |
| 1857 | gold_assert(i != 0 && i != -1U); |
| 1858 | this->output_dynsym_index_ = i; |
| 1859 | } |
| 1860 | |
| 1861 | // Return the index in the output dynamic symbol table. |
| 1862 | unsigned int |
| 1863 | output_dynsym_index() const |
| 1864 | { |
| 1865 | gold_assert(this->output_dynsym_index_ != 0 |
| 1866 | && this->output_dynsym_index_ != -1U); |
| 1867 | return this->output_dynsym_index_; |
| 1868 | } |
| 1869 | |
| 1870 | // Set the index of the input section in the input file. |
| 1871 | void |
| 1872 | set_input_shndx(unsigned int i, bool is_ordinary) |
| 1873 | { |
| 1874 | this->input_shndx_ = i; |
| 1875 | // input_shndx_ field is a bitfield, so make sure that the value |
| 1876 | // fits. |
| 1877 | gold_assert(this->input_shndx_ == i); |
| 1878 | this->is_ordinary_shndx_ = is_ordinary; |
| 1879 | } |
| 1880 | |
| 1881 | // Return the index of the input section in the input file. |
| 1882 | unsigned int |
| 1883 | input_shndx(bool* is_ordinary) const |
| 1884 | { |
| 1885 | *is_ordinary = this->is_ordinary_shndx_; |
| 1886 | return this->input_shndx_; |
| 1887 | } |
| 1888 | |
| 1889 | // Whether this is a section symbol. |
| 1890 | bool |
| 1891 | is_section_symbol() const |
| 1892 | { return this->is_section_symbol_; } |
| 1893 | |
| 1894 | // Record that this is a section symbol. |
| 1895 | void |
| 1896 | set_is_section_symbol() |
| 1897 | { |
| 1898 | gold_assert(!this->needs_output_dynsym_entry()); |
| 1899 | this->is_section_symbol_ = true; |
| 1900 | } |
| 1901 | |
| 1902 | // Record that this is a TLS symbol. |
| 1903 | void |
| 1904 | set_is_tls_symbol() |
| 1905 | { this->is_tls_symbol_ = true; } |
| 1906 | |
| 1907 | // Return true if this is a TLS symbol. |
| 1908 | bool |
| 1909 | is_tls_symbol() const |
| 1910 | { return this->is_tls_symbol_; } |
| 1911 | |
| 1912 | // Record that this is an IFUNC symbol. |
| 1913 | void |
| 1914 | set_is_ifunc_symbol() |
| 1915 | { this->is_ifunc_symbol_ = true; } |
| 1916 | |
| 1917 | // Return true if this is an IFUNC symbol. |
| 1918 | bool |
| 1919 | is_ifunc_symbol() const |
| 1920 | { return this->is_ifunc_symbol_; } |
| 1921 | |
| 1922 | // Return true if this has output value. |
| 1923 | bool |
| 1924 | has_output_value() const |
| 1925 | { return this->has_output_value_; } |
| 1926 | |
| 1927 | private: |
| 1928 | // The index of this local symbol in the output symbol table. This |
| 1929 | // will be 0 if no value has been assigned yet, and the symbol may |
| 1930 | // be omitted. This will be -1U if the symbol should not go into |
| 1931 | // the symbol table. This will be -2U if the symbol must go into |
| 1932 | // the symbol table, but no index has been assigned yet. |
| 1933 | unsigned int output_symtab_index_; |
| 1934 | // The index of this local symbol in the dynamic symbol table. This |
| 1935 | // will be -1U if the symbol should not go into the symbol table. |
| 1936 | unsigned int output_dynsym_index_; |
| 1937 | // The section index in the input file in which this symbol is |
| 1938 | // defined. |
| 1939 | unsigned int input_shndx_ : 27; |
| 1940 | // Whether the section index is an ordinary index, not a special |
| 1941 | // value. |
| 1942 | bool is_ordinary_shndx_ : 1; |
| 1943 | // Whether this is a STT_SECTION symbol. |
| 1944 | bool is_section_symbol_ : 1; |
| 1945 | // Whether this is a STT_TLS symbol. |
| 1946 | bool is_tls_symbol_ : 1; |
| 1947 | // Whether this is a STT_GNU_IFUNC symbol. |
| 1948 | bool is_ifunc_symbol_ : 1; |
| 1949 | // Whether this symbol has a value for the output file. This is |
| 1950 | // normally set to true during Layout::finalize, by |
| 1951 | // finalize_local_symbols. It will be false for a section symbol in |
| 1952 | // a merge section, as for such symbols we can not determine the |
| 1953 | // value to use in a relocation until we see the addend. |
| 1954 | bool has_output_value_ : 1; |
| 1955 | union |
| 1956 | { |
| 1957 | // This is used if has_output_value_ is true. Between |
| 1958 | // count_local_symbols and finalize_local_symbols, this is the |
| 1959 | // value in the input file. After finalize_local_symbols, it is |
| 1960 | // the value in the output file. |
| 1961 | Value value; |
| 1962 | // This is used if has_output_value_ is false. It points to the |
| 1963 | // information we need to get the value for a merge section. |
| 1964 | Merged_symbol_value<size>* merged_symbol_value; |
| 1965 | } u_; |
| 1966 | }; |
| 1967 | |
| 1968 | // This type is used to modify relocations for -fsplit-stack. It is |
| 1969 | // indexed by relocation index, and means that the relocation at that |
| 1970 | // index should use the symbol from the vector, rather than the one |
| 1971 | // indicated by the relocation. |
| 1972 | |
| 1973 | class Reloc_symbol_changes |
| 1974 | { |
| 1975 | public: |
| 1976 | Reloc_symbol_changes(size_t count) |
| 1977 | : vec_(count, NULL) |
| 1978 | { } |
| 1979 | |
| 1980 | void |
| 1981 | set(size_t i, Symbol* sym) |
| 1982 | { this->vec_[i] = sym; } |
| 1983 | |
| 1984 | const Symbol* |
| 1985 | operator[](size_t i) const |
| 1986 | { return this->vec_[i]; } |
| 1987 | |
| 1988 | private: |
| 1989 | std::vector<Symbol*> vec_; |
| 1990 | }; |
| 1991 | |
| 1992 | // Abstract base class for a regular object file, either a real object file |
| 1993 | // or an incremental (unchanged) object. This is size and endian specific. |
| 1994 | |
| 1995 | template<int size, bool big_endian> |
| 1996 | class Sized_relobj : public Relobj |
| 1997 | { |
| 1998 | public: |
| 1999 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Address; |
| 2000 | typedef Relobj::Symbols Symbols; |
| 2001 | |
| 2002 | static const Address invalid_address = static_cast<Address>(0) - 1; |
| 2003 | |
| 2004 | Sized_relobj(const std::string& name, Input_file* input_file) |
| 2005 | : Relobj(name, input_file), local_got_offsets_(), section_offsets_() |
| 2006 | { } |
| 2007 | |
| 2008 | Sized_relobj(const std::string& name, Input_file* input_file, |
| 2009 | off_t offset) |
| 2010 | : Relobj(name, input_file, offset), local_got_offsets_(), section_offsets_() |
| 2011 | { } |
| 2012 | |
| 2013 | ~Sized_relobj() |
| 2014 | { } |
| 2015 | |
| 2016 | // If this is a regular object, return a pointer to the Sized_relobj_file |
| 2017 | // object. Otherwise, return NULL. |
| 2018 | virtual Sized_relobj_file<size, big_endian>* |
| 2019 | sized_relobj() |
| 2020 | { return NULL; } |
| 2021 | |
| 2022 | const virtual Sized_relobj_file<size, big_endian>* |
| 2023 | sized_relobj() const |
| 2024 | { return NULL; } |
| 2025 | |
| 2026 | // Checks if the offset of input section SHNDX within its output |
| 2027 | // section is invalid. |
| 2028 | bool |
| 2029 | is_output_section_offset_invalid(unsigned int shndx) const |
| 2030 | { return this->get_output_section_offset(shndx) == invalid_address; } |
| 2031 | |
| 2032 | // Get the offset of input section SHNDX within its output section. |
| 2033 | // This is -1 if the input section requires a special mapping, such |
| 2034 | // as a merge section. The output section can be found in the |
| 2035 | // output_sections_ field of the parent class Relobj. |
| 2036 | Address |
| 2037 | get_output_section_offset(unsigned int shndx) const |
| 2038 | { |
| 2039 | gold_assert(shndx < this->section_offsets_.size()); |
| 2040 | return this->section_offsets_[shndx]; |
| 2041 | } |
| 2042 | |
| 2043 | // Iterate over local symbols, calling a visitor class V for each GOT offset |
| 2044 | // associated with a local symbol. |
| 2045 | void |
| 2046 | do_for_all_local_got_entries(Got_offset_list::Visitor* v) const; |
| 2047 | |
| 2048 | protected: |
| 2049 | typedef Relobj::Output_sections Output_sections; |
| 2050 | |
| 2051 | // Clear the local symbol information. |
| 2052 | void |
| 2053 | clear_got_offsets() |
| 2054 | { this->local_got_offsets_.clear(); } |
| 2055 | |
| 2056 | // Return the vector of section offsets. |
| 2057 | std::vector<Address>& |
| 2058 | section_offsets() |
| 2059 | { return this->section_offsets_; } |
| 2060 | |
| 2061 | // Get the address of an output section. |
| 2062 | uint64_t |
| 2063 | do_output_section_address(unsigned int shndx); |
| 2064 | |
| 2065 | // Get the offset of a section. |
| 2066 | uint64_t |
| 2067 | do_output_section_offset(unsigned int shndx) const |
| 2068 | { |
| 2069 | Address off = this->get_output_section_offset(shndx); |
| 2070 | if (off == invalid_address) |
| 2071 | return -1ULL; |
| 2072 | return off; |
| 2073 | } |
| 2074 | |
| 2075 | // Set the offset of a section. |
| 2076 | void |
| 2077 | do_set_section_offset(unsigned int shndx, uint64_t off) |
| 2078 | { |
| 2079 | gold_assert(shndx < this->section_offsets_.size()); |
| 2080 | this->section_offsets_[shndx] = |
| 2081 | (off == static_cast<uint64_t>(-1) |
| 2082 | ? invalid_address |
| 2083 | : convert_types<Address, uint64_t>(off)); |
| 2084 | } |
| 2085 | |
| 2086 | // Return whether the local symbol SYMNDX plus ADDEND has a GOT offset |
| 2087 | // of type GOT_TYPE. |
| 2088 | bool |
| 2089 | do_local_has_got_offset(unsigned int symndx, unsigned int got_type, |
| 2090 | uint64_t addend) const |
| 2091 | { |
| 2092 | Local_got_entry_key key(symndx, addend); |
| 2093 | Local_got_offsets::const_iterator p = |
| 2094 | this->local_got_offsets_.find(key); |
| 2095 | return (p != this->local_got_offsets_.end() |
| 2096 | && p->second->get_offset(got_type) != -1U); |
| 2097 | } |
| 2098 | |
| 2099 | // Return the GOT offset of type GOT_TYPE of the local symbol |
| 2100 | // SYMNDX plus ADDEND. |
| 2101 | unsigned int |
| 2102 | do_local_got_offset(unsigned int symndx, unsigned int got_type, |
| 2103 | uint64_t addend) const |
| 2104 | { |
| 2105 | Local_got_entry_key key(symndx, addend); |
| 2106 | Local_got_offsets::const_iterator p = |
| 2107 | this->local_got_offsets_.find(key); |
| 2108 | gold_assert(p != this->local_got_offsets_.end()); |
| 2109 | unsigned int off = p->second->get_offset(got_type); |
| 2110 | gold_assert(off != -1U); |
| 2111 | return off; |
| 2112 | } |
| 2113 | |
| 2114 | // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX |
| 2115 | // plus ADDEND to GOT_OFFSET. |
| 2116 | void |
| 2117 | do_set_local_got_offset(unsigned int symndx, unsigned int got_type, |
| 2118 | unsigned int got_offset, uint64_t addend) |
| 2119 | { |
| 2120 | Local_got_entry_key key(symndx, addend); |
| 2121 | Local_got_offsets::const_iterator p = |
| 2122 | this->local_got_offsets_.find(key); |
| 2123 | if (p != this->local_got_offsets_.end()) |
| 2124 | p->second->set_offset(got_type, got_offset); |
| 2125 | else |
| 2126 | { |
| 2127 | Got_offset_list* g = new Got_offset_list(got_type, got_offset); |
| 2128 | std::pair<Local_got_offsets::iterator, bool> ins = |
| 2129 | this->local_got_offsets_.insert(std::make_pair(key, g)); |
| 2130 | gold_assert(ins.second); |
| 2131 | } |
| 2132 | } |
| 2133 | |
| 2134 | // Return the word size of the object file. |
| 2135 | virtual int |
| 2136 | do_elfsize() const |
| 2137 | { return size; } |
| 2138 | |
| 2139 | // Return TRUE if this is a big-endian object file. |
| 2140 | virtual bool |
| 2141 | do_is_big_endian() const |
| 2142 | { return big_endian; } |
| 2143 | |
| 2144 | private: |
| 2145 | // The GOT offsets of local symbols. This map also stores GOT offsets |
| 2146 | // for tp-relative offsets for TLS symbols. |
| 2147 | typedef Unordered_map<Local_got_entry_key, Got_offset_list*, |
| 2148 | Local_got_entry_key::hash, |
| 2149 | Local_got_entry_key::equal_to> Local_got_offsets; |
| 2150 | |
| 2151 | // GOT offsets for local non-TLS symbols, and tp-relative offsets |
| 2152 | // for TLS symbols, indexed by local got entry key class. |
| 2153 | Local_got_offsets local_got_offsets_; |
| 2154 | // For each input section, the offset of the input section in its |
| 2155 | // output section. This is INVALID_ADDRESS if the input section requires a |
| 2156 | // special mapping. |
| 2157 | std::vector<Address> section_offsets_; |
| 2158 | }; |
| 2159 | |
| 2160 | // A regular object file. This is size and endian specific. |
| 2161 | |
| 2162 | template<int size, bool big_endian> |
| 2163 | class Sized_relobj_file : public Sized_relobj<size, big_endian> |
| 2164 | { |
| 2165 | public: |
| 2166 | typedef typename elfcpp::Elf_types<size>::Elf_Addr Address; |
| 2167 | typedef typename Sized_relobj<size, big_endian>::Symbols Symbols; |
| 2168 | typedef std::vector<Symbol_value<size> > Local_values; |
| 2169 | |
| 2170 | static const Address invalid_address = static_cast<Address>(0) - 1; |
| 2171 | |
| 2172 | enum Compute_final_local_value_status |
| 2173 | { |
| 2174 | // No error. |
| 2175 | CFLV_OK, |
| 2176 | // An error occurred. |
| 2177 | CFLV_ERROR, |
| 2178 | // The local symbol has no output section. |
| 2179 | CFLV_DISCARDED |
| 2180 | }; |
| 2181 | |
| 2182 | Sized_relobj_file(const std::string& name, |
| 2183 | Input_file* input_file, |
| 2184 | off_t offset, |
| 2185 | const typename elfcpp::Ehdr<size, big_endian>&); |
| 2186 | |
| 2187 | ~Sized_relobj_file(); |
| 2188 | |
| 2189 | // Set up the object file based on TARGET. |
| 2190 | void |
| 2191 | setup() |
| 2192 | { this->do_setup(); } |
| 2193 | |
| 2194 | // Return a pointer to the Sized_relobj_file object. |
| 2195 | Sized_relobj_file<size, big_endian>* |
| 2196 | sized_relobj() |
| 2197 | { return this; } |
| 2198 | |
| 2199 | const Sized_relobj_file<size, big_endian>* |
| 2200 | sized_relobj() const |
| 2201 | { return this; } |
| 2202 | |
| 2203 | // Return the ELF file type. |
| 2204 | int |
| 2205 | e_type() const |
| 2206 | { return this->e_type_; } |
| 2207 | |
| 2208 | // Return the number of symbols. This is only valid after |
| 2209 | // Object::add_symbols has been called. |
| 2210 | unsigned int |
| 2211 | symbol_count() const |
| 2212 | { return this->local_symbol_count_ + this->symbols_.size(); } |
| 2213 | |
| 2214 | // If SYM is the index of a global symbol in the object file's |
| 2215 | // symbol table, return the Symbol object. Otherwise, return NULL. |
| 2216 | Symbol* |
| 2217 | global_symbol(unsigned int sym) const |
| 2218 | { |
| 2219 | if (sym >= this->local_symbol_count_) |
| 2220 | { |
| 2221 | gold_assert(sym - this->local_symbol_count_ < this->symbols_.size()); |
| 2222 | return this->symbols_[sym - this->local_symbol_count_]; |
| 2223 | } |
| 2224 | return NULL; |
| 2225 | } |
| 2226 | |
| 2227 | // Return the section index of symbol SYM. Set *VALUE to its value |
| 2228 | // in the object file. Set *IS_ORDINARY if this is an ordinary |
| 2229 | // section index, not a special code between SHN_LORESERVE and |
| 2230 | // SHN_HIRESERVE. Note that for a symbol which is not defined in |
| 2231 | // this object file, this will set *VALUE to 0 and return SHN_UNDEF; |
| 2232 | // it will not return the final value of the symbol in the link. |
| 2233 | unsigned int |
| 2234 | symbol_section_and_value(unsigned int sym, Address* value, bool* is_ordinary); |
| 2235 | |
| 2236 | // Return a pointer to the Symbol_value structure which holds the |
| 2237 | // value of a local symbol. |
| 2238 | const Symbol_value<size>* |
| 2239 | local_symbol(unsigned int sym) const |
| 2240 | { |
| 2241 | gold_assert(sym < this->local_values_.size()); |
| 2242 | return &this->local_values_[sym]; |
| 2243 | } |
| 2244 | |
| 2245 | // Return the index of local symbol SYM in the ordinary symbol |
| 2246 | // table. A value of -1U means that the symbol is not being output. |
| 2247 | unsigned int |
| 2248 | symtab_index(unsigned int sym) const |
| 2249 | { |
| 2250 | gold_assert(sym < this->local_values_.size()); |
| 2251 | return this->local_values_[sym].output_symtab_index(); |
| 2252 | } |
| 2253 | |
| 2254 | // Return the index of local symbol SYM in the dynamic symbol |
| 2255 | // table. A value of -1U means that the symbol is not being output. |
| 2256 | unsigned int |
| 2257 | dynsym_index(unsigned int sym) const |
| 2258 | { |
| 2259 | gold_assert(sym < this->local_values_.size()); |
| 2260 | return this->local_values_[sym].output_dynsym_index(); |
| 2261 | } |
| 2262 | |
| 2263 | // Return the input section index of local symbol SYM. |
| 2264 | unsigned int |
| 2265 | local_symbol_input_shndx(unsigned int sym, bool* is_ordinary) const |
| 2266 | { |
| 2267 | gold_assert(sym < this->local_values_.size()); |
| 2268 | return this->local_values_[sym].input_shndx(is_ordinary); |
| 2269 | } |
| 2270 | |
| 2271 | // Record that local symbol SYM must be in the output symbol table. |
| 2272 | void |
| 2273 | set_must_have_output_symtab_entry(unsigned int sym) |
| 2274 | { |
| 2275 | gold_assert(sym < this->local_values_.size()); |
| 2276 | this->local_values_[sym].set_must_have_output_symtab_entry(); |
| 2277 | } |
| 2278 | |
| 2279 | // Record that local symbol SYM needs a dynamic symbol entry. |
| 2280 | void |
| 2281 | set_needs_output_dynsym_entry(unsigned int sym) |
| 2282 | { |
| 2283 | gold_assert(sym < this->local_values_.size()); |
| 2284 | this->local_values_[sym].set_needs_output_dynsym_entry(); |
| 2285 | } |
| 2286 | |
| 2287 | // Return whether the local symbol SYMNDX has a PLT offset. |
| 2288 | bool |
| 2289 | local_has_plt_offset(unsigned int symndx) const; |
| 2290 | |
| 2291 | // Set the PLT offset of the local symbol SYMNDX. |
| 2292 | void |
| 2293 | set_local_plt_offset(unsigned int symndx, unsigned int plt_offset); |
| 2294 | |
| 2295 | // Adjust this local symbol value. Return false if the symbol |
| 2296 | // should be discarded from the output file. |
| 2297 | bool |
| 2298 | adjust_local_symbol(Symbol_value<size>* lv) const |
| 2299 | { return this->do_adjust_local_symbol(lv); } |
| 2300 | |
| 2301 | // Return the name of the symbol that spans the given offset in the |
| 2302 | // specified section in this object. This is used only for error |
| 2303 | // messages and is not particularly efficient. |
| 2304 | bool |
| 2305 | get_symbol_location_info(unsigned int shndx, off_t offset, |
| 2306 | Symbol_location_info* info); |
| 2307 | |
| 2308 | // Look for a kept section corresponding to the given discarded section, |
| 2309 | // and return its output address. This is used only for relocations in |
| 2310 | // debugging sections. |
| 2311 | Address |
| 2312 | map_to_kept_section(unsigned int shndx, std::string& section_name, |
| 2313 | bool* found) const; |
| 2314 | |
| 2315 | // Look for a kept section corresponding to the given discarded section, |
| 2316 | // and return its object file. |
| 2317 | Relobj* |
| 2318 | find_kept_section_object(unsigned int shndx, unsigned int* symndx_p) const; |
| 2319 | |
| 2320 | // Return the name of symbol SYMNDX. |
| 2321 | const char* |
| 2322 | get_symbol_name(unsigned int symndx); |
| 2323 | |
| 2324 | // Compute final local symbol value. R_SYM is the local symbol index. |
| 2325 | // LV_IN points to a local symbol value containing the input value. |
| 2326 | // LV_OUT points to a local symbol value storing the final output value, |
| 2327 | // which must not be a merged symbol value since before calling this |
| 2328 | // method to avoid memory leak. SYMTAB points to a symbol table. |
| 2329 | // |
| 2330 | // The method returns a status code at return. If the return status is |
| 2331 | // CFLV_OK, *LV_OUT contains the final value. If the return status is |
| 2332 | // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED, |
| 2333 | // *LV_OUT is not modified. |
| 2334 | Compute_final_local_value_status |
| 2335 | compute_final_local_value(unsigned int r_sym, |
| 2336 | const Symbol_value<size>* lv_in, |
| 2337 | Symbol_value<size>* lv_out, |
| 2338 | const Symbol_table* symtab); |
| 2339 | |
| 2340 | // Return true if the layout for this object was deferred. |
| 2341 | bool is_deferred_layout() const |
| 2342 | { return this->is_deferred_layout_; } |
| 2343 | |
| 2344 | protected: |
| 2345 | typedef typename Sized_relobj<size, big_endian>::Output_sections |
| 2346 | Output_sections; |
| 2347 | |
| 2348 | // Set up. |
| 2349 | virtual void |
| 2350 | do_setup(); |
| 2351 | |
| 2352 | // Read the symbols. |
| 2353 | void |
| 2354 | do_read_symbols(Read_symbols_data*); |
| 2355 | |
| 2356 | // Read the symbols. This is common code for all target-specific |
| 2357 | // overrides of do_read_symbols. |
| 2358 | void |
| 2359 | base_read_symbols(Read_symbols_data*); |
| 2360 | |
| 2361 | // Return the value of a local symbol. |
| 2362 | uint64_t |
| 2363 | do_local_symbol_value(unsigned int symndx, uint64_t addend) const |
| 2364 | { |
| 2365 | const Symbol_value<size>* symval = this->local_symbol(symndx); |
| 2366 | return symval->value(this, addend); |
| 2367 | } |
| 2368 | |
| 2369 | // Return the PLT offset for a local symbol. It is an error to call |
| 2370 | // this if it doesn't have one. |
| 2371 | unsigned int |
| 2372 | do_local_plt_offset(unsigned int symndx) const; |
| 2373 | |
| 2374 | // Return whether local symbol SYMNDX is a TLS symbol. |
| 2375 | bool |
| 2376 | do_local_is_tls(unsigned int symndx) const |
| 2377 | { return this->local_symbol(symndx)->is_tls_symbol(); } |
| 2378 | |
| 2379 | // Return the number of local symbols. |
| 2380 | unsigned int |
| 2381 | do_local_symbol_count() const |
| 2382 | { return this->local_symbol_count_; } |
| 2383 | |
| 2384 | // Return the number of local symbols in the output symbol table. |
| 2385 | unsigned int |
| 2386 | do_output_local_symbol_count() const |
| 2387 | { return this->output_local_symbol_count_; } |
| 2388 | |
| 2389 | // Return the number of local symbols in the output symbol table. |
| 2390 | off_t |
| 2391 | do_local_symbol_offset() const |
| 2392 | { return this->local_symbol_offset_; } |
| 2393 | |
| 2394 | // Lay out the input sections. |
| 2395 | void |
| 2396 | do_layout(Symbol_table*, Layout*, Read_symbols_data*); |
| 2397 | |
| 2398 | // Layout sections whose layout was deferred while waiting for |
| 2399 | // input files from a plugin. |
| 2400 | void |
| 2401 | do_layout_deferred_sections(Layout*); |
| 2402 | |
| 2403 | // Add the symbols to the symbol table. |
| 2404 | void |
| 2405 | do_add_symbols(Symbol_table*, Read_symbols_data*, Layout*); |
| 2406 | |
| 2407 | Archive::Should_include |
| 2408 | do_should_include_member(Symbol_table* symtab, Layout*, Read_symbols_data*, |
| 2409 | std::string* why); |
| 2410 | |
| 2411 | // Iterate over global symbols, calling a visitor class V for each. |
| 2412 | void |
| 2413 | do_for_all_global_symbols(Read_symbols_data* sd, |
| 2414 | Library_base::Symbol_visitor_base* v); |
| 2415 | |
| 2416 | // Read the relocs. |
| 2417 | void |
| 2418 | do_read_relocs(Read_relocs_data*); |
| 2419 | |
| 2420 | // Process the relocs to find list of referenced sections. Used only |
| 2421 | // during garbage collection. |
| 2422 | void |
| 2423 | do_gc_process_relocs(Symbol_table*, Layout*, Read_relocs_data*); |
| 2424 | |
| 2425 | // Scan the relocs and adjust the symbol table. |
| 2426 | void |
| 2427 | do_scan_relocs(Symbol_table*, Layout*, Read_relocs_data*); |
| 2428 | |
| 2429 | // Count the local symbols. |
| 2430 | void |
| 2431 | do_count_local_symbols(Stringpool_template<char>*, |
| 2432 | Stringpool_template<char>*); |
| 2433 | |
| 2434 | // Finalize the local symbols. |
| 2435 | unsigned int |
| 2436 | do_finalize_local_symbols(unsigned int, off_t, Symbol_table*); |
| 2437 | |
| 2438 | // Set the offset where local dynamic symbol information will be stored. |
| 2439 | unsigned int |
| 2440 | do_set_local_dynsym_indexes(unsigned int); |
| 2441 | |
| 2442 | // Set the offset where local dynamic symbol information will be stored. |
| 2443 | unsigned int |
| 2444 | do_set_local_dynsym_offset(off_t); |
| 2445 | |
| 2446 | // Relocate the input sections and write out the local symbols. |
| 2447 | void |
| 2448 | do_relocate(const Symbol_table* symtab, const Layout*, Output_file* of); |
| 2449 | |
| 2450 | // Get the size of a section. |
| 2451 | uint64_t |
| 2452 | do_section_size(unsigned int shndx) |
| 2453 | { return this->elf_file_.section_size(shndx); } |
| 2454 | |
| 2455 | // Get the name of a section. |
| 2456 | std::string |
| 2457 | do_section_name(unsigned int shndx) const |
| 2458 | { return this->elf_file_.section_name(shndx); } |
| 2459 | |
| 2460 | // Return the location of the contents of a section. |
| 2461 | const unsigned char* |
| 2462 | do_section_contents(unsigned int shndx, section_size_type* plen, |
| 2463 | bool cache) |
| 2464 | { |
| 2465 | Object::Location loc(this->elf_file_.section_contents(shndx)); |
| 2466 | *plen = convert_to_section_size_type(loc.data_size); |
| 2467 | if (*plen == 0) |
| 2468 | { |
| 2469 | static const unsigned char empty[1] = { '\0' }; |
| 2470 | return empty; |
| 2471 | } |
| 2472 | return this->get_view(loc.file_offset, *plen, true, cache); |
| 2473 | } |
| 2474 | |
| 2475 | // Return section flags. |
| 2476 | uint64_t |
| 2477 | do_section_flags(unsigned int shndx); |
| 2478 | |
| 2479 | // Return section entsize. |
| 2480 | uint64_t |
| 2481 | do_section_entsize(unsigned int shndx); |
| 2482 | |
| 2483 | // Return section address. |
| 2484 | uint64_t |
| 2485 | do_section_address(unsigned int shndx) |
| 2486 | { return this->elf_file_.section_addr(shndx); } |
| 2487 | |
| 2488 | // Return section type. |
| 2489 | unsigned int |
| 2490 | do_section_type(unsigned int shndx) |
| 2491 | { return this->elf_file_.section_type(shndx); } |
| 2492 | |
| 2493 | // Return the section link field. |
| 2494 | unsigned int |
| 2495 | do_section_link(unsigned int shndx) |
| 2496 | { return this->elf_file_.section_link(shndx); } |
| 2497 | |
| 2498 | // Return the section info field. |
| 2499 | unsigned int |
| 2500 | do_section_info(unsigned int shndx) |
| 2501 | { return this->elf_file_.section_info(shndx); } |
| 2502 | |
| 2503 | // Return the section alignment. |
| 2504 | uint64_t |
| 2505 | do_section_addralign(unsigned int shndx) |
| 2506 | { return this->elf_file_.section_addralign(shndx); } |
| 2507 | |
| 2508 | // Return the Xindex structure to use. |
| 2509 | Xindex* |
| 2510 | do_initialize_xindex(); |
| 2511 | |
| 2512 | // Get symbol counts. |
| 2513 | void |
| 2514 | do_get_global_symbol_counts(const Symbol_table*, size_t*, size_t*) const; |
| 2515 | |
| 2516 | // Get the global symbols. |
| 2517 | const Symbols* |
| 2518 | do_get_global_symbols() const |
| 2519 | { return &this->symbols_; } |
| 2520 | |
| 2521 | // Adjust a section index if necessary. |
| 2522 | unsigned int |
| 2523 | adjust_shndx(unsigned int shndx) |
| 2524 | { |
| 2525 | if (shndx >= elfcpp::SHN_LORESERVE) |
| 2526 | shndx += this->elf_file_.large_shndx_offset(); |
| 2527 | return shndx; |
| 2528 | } |
| 2529 | |
| 2530 | // Initialize input to output maps for section symbols in merged |
| 2531 | // sections. |
| 2532 | void |
| 2533 | initialize_input_to_output_maps(); |
| 2534 | |
| 2535 | // Free the input to output maps for section symbols in merged |
| 2536 | // sections. |
| 2537 | void |
| 2538 | free_input_to_output_maps(); |
| 2539 | |
| 2540 | // Return symbol table section index. |
| 2541 | unsigned int |
| 2542 | symtab_shndx() const |
| 2543 | { return this->symtab_shndx_; } |
| 2544 | |
| 2545 | // Allow a child class to access the ELF file. |
| 2546 | elfcpp::Elf_file<size, big_endian, Object>* |
| 2547 | elf_file() |
| 2548 | { return &this->elf_file_; } |
| 2549 | |
| 2550 | // Allow a child class to access the local values. |
| 2551 | Local_values* |
| 2552 | local_values() |
| 2553 | { return &this->local_values_; } |
| 2554 | |
| 2555 | // Views and sizes when relocating. |
| 2556 | struct View_size |
| 2557 | { |
| 2558 | unsigned char* view; |
| 2559 | typename elfcpp::Elf_types<size>::Elf_Addr address; |
| 2560 | off_t offset; |
| 2561 | section_size_type view_size; |
| 2562 | bool is_input_output_view; |
| 2563 | bool is_postprocessing_view; |
| 2564 | bool is_ctors_reverse_view; |
| 2565 | }; |
| 2566 | |
| 2567 | typedef std::vector<View_size> Views; |
| 2568 | |
| 2569 | // Stash away info for a number of special sections. |
| 2570 | // Return true if any of the sections found require local symbols to be read. |
| 2571 | virtual bool |
| 2572 | do_find_special_sections(Read_symbols_data* sd); |
| 2573 | |
| 2574 | // This may be overriden by a child class. |
| 2575 | virtual void |
| 2576 | do_relocate_sections(const Symbol_table* symtab, const Layout* layout, |
| 2577 | const unsigned char* pshdrs, Output_file* of, |
| 2578 | Views* pviews); |
| 2579 | |
| 2580 | // Relocate section data for a range of sections. |
| 2581 | void |
| 2582 | relocate_section_range(const Symbol_table* symtab, const Layout* layout, |
| 2583 | const unsigned char* pshdrs, Output_file* of, |
| 2584 | Views* pviews, unsigned int start_shndx, |
| 2585 | unsigned int end_shndx); |
| 2586 | |
| 2587 | // Adjust this local symbol value. Return false if the symbol |
| 2588 | // should be discarded from the output file. |
| 2589 | virtual bool |
| 2590 | do_adjust_local_symbol(Symbol_value<size>*) const |
| 2591 | { return true; } |
| 2592 | |
| 2593 | // Allow a child to set output local symbol count. |
| 2594 | void |
| 2595 | set_output_local_symbol_count(unsigned int value) |
| 2596 | { this->output_local_symbol_count_ = value; } |
| 2597 | |
| 2598 | // Return the output view for a section. |
| 2599 | unsigned char* |
| 2600 | do_get_output_view(unsigned int, section_size_type*) const; |
| 2601 | |
| 2602 | private: |
| 2603 | // For convenience. |
| 2604 | typedef Sized_relobj_file<size, big_endian> This; |
| 2605 | static const int ehdr_size = elfcpp::Elf_sizes<size>::ehdr_size; |
| 2606 | static const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size; |
| 2607 | static const int sym_size = elfcpp::Elf_sizes<size>::sym_size; |
| 2608 | typedef elfcpp::Shdr<size, big_endian> Shdr; |
| 2609 | typedef elfcpp::Shdr_write<size, big_endian> Shdr_write; |
| 2610 | |
| 2611 | // To keep track of discarded comdat sections, we need to map a member |
| 2612 | // section index to the object and section index of the corresponding |
| 2613 | // kept section. |
| 2614 | struct Kept_comdat_section |
| 2615 | { |
| 2616 | Kept_comdat_section(uint64_t a_sh_size, Kept_section* a_kept_section, |
| 2617 | unsigned int a_symndx, bool a_is_comdat) |
| 2618 | : sh_size(a_sh_size), kept_section(a_kept_section), |
| 2619 | symndx (a_symndx), is_comdat(a_is_comdat) |
| 2620 | { } |
| 2621 | uint64_t sh_size; // Section size |
| 2622 | Kept_section* kept_section; // Kept section info |
| 2623 | unsigned int symndx; // Index of key symbol |
| 2624 | bool is_comdat; // True if comdat group, false if linkonce |
| 2625 | }; |
| 2626 | typedef std::map<unsigned int, Kept_comdat_section> |
| 2627 | Kept_comdat_section_table; |
| 2628 | |
| 2629 | // Find the SHT_SYMTAB section, given the section headers. |
| 2630 | void |
| 2631 | find_symtab(const unsigned char* pshdrs); |
| 2632 | |
| 2633 | // Return whether SHDR has the right flags for a GNU style exception |
| 2634 | // frame section. |
| 2635 | bool |
| 2636 | check_eh_frame_flags(const elfcpp::Shdr<size, big_endian>* shdr) const; |
| 2637 | |
| 2638 | // Return whether there is a section named .eh_frame which might be |
| 2639 | // a GNU style exception frame section. |
| 2640 | bool |
| 2641 | find_eh_frame(const unsigned char* pshdrs, const char* names, |
| 2642 | section_size_type names_size) const; |
| 2643 | |
| 2644 | // Whether to include a section group in the link. |
| 2645 | bool |
| 2646 | include_section_group(Symbol_table*, Layout*, unsigned int, const char*, |
| 2647 | const unsigned char*, const char*, section_size_type, |
| 2648 | std::vector<bool>*); |
| 2649 | |
| 2650 | // Whether to include a linkonce section in the link. |
| 2651 | bool |
| 2652 | include_linkonce_section(Layout*, unsigned int, const char*, |
| 2653 | const elfcpp::Shdr<size, big_endian>&); |
| 2654 | |
| 2655 | // Layout an input section. |
| 2656 | void |
| 2657 | layout_section(Layout* layout, unsigned int shndx, const char* name, |
| 2658 | const typename This::Shdr& shdr, unsigned int sh_type, |
| 2659 | unsigned int reloc_shndx, unsigned int reloc_type); |
| 2660 | |
| 2661 | // Layout an input .eh_frame section. |
| 2662 | void |
| 2663 | layout_eh_frame_section(Layout* layout, const unsigned char* symbols_data, |
| 2664 | section_size_type symbols_size, |
| 2665 | const unsigned char* symbol_names_data, |
| 2666 | section_size_type symbol_names_size, |
| 2667 | unsigned int shndx, const typename This::Shdr&, |
| 2668 | unsigned int reloc_shndx, unsigned int reloc_type); |
| 2669 | |
| 2670 | // Layout an input .note.gnu.property section. |
| 2671 | void |
| 2672 | layout_gnu_property_section(Layout* layout, unsigned int shndx); |
| 2673 | |
| 2674 | // Write section data to the output file. Record the views and |
| 2675 | // sizes in VIEWS for use when relocating. |
| 2676 | void |
| 2677 | write_sections(const Layout*, const unsigned char* pshdrs, Output_file*, |
| 2678 | Views*); |
| 2679 | |
| 2680 | // Relocate the sections in the output file. |
| 2681 | void |
| 2682 | relocate_sections(const Symbol_table* symtab, const Layout* layout, |
| 2683 | const unsigned char* pshdrs, Output_file* of, |
| 2684 | Views* pviews) |
| 2685 | { this->do_relocate_sections(symtab, layout, pshdrs, of, pviews); } |
| 2686 | |
| 2687 | // Reverse the words in a section. Used for .ctors sections mapped |
| 2688 | // to .init_array sections. |
| 2689 | void |
| 2690 | reverse_words(unsigned char*, section_size_type); |
| 2691 | |
| 2692 | // Scan the input relocations for --emit-relocs. |
| 2693 | void |
| 2694 | emit_relocs_scan(Symbol_table*, Layout*, const unsigned char* plocal_syms, |
| 2695 | const Read_relocs_data::Relocs_list::iterator&); |
| 2696 | |
| 2697 | // Scan the input relocations for --emit-relocs, templatized on the |
| 2698 | // type of the relocation section. |
| 2699 | template<int sh_type> |
| 2700 | void |
| 2701 | emit_relocs_scan_reltype(Symbol_table*, Layout*, |
| 2702 | const unsigned char* plocal_syms, |
| 2703 | const Read_relocs_data::Relocs_list::iterator&, |
| 2704 | Relocatable_relocs*); |
| 2705 | |
| 2706 | // Scan the input relocations for --incremental. |
| 2707 | void |
| 2708 | incremental_relocs_scan(const Read_relocs_data::Relocs_list::iterator&); |
| 2709 | |
| 2710 | // Scan the input relocations for --incremental, templatized on the |
| 2711 | // type of the relocation section. |
| 2712 | template<int sh_type> |
| 2713 | void |
| 2714 | incremental_relocs_scan_reltype( |
| 2715 | const Read_relocs_data::Relocs_list::iterator&); |
| 2716 | |
| 2717 | void |
| 2718 | incremental_relocs_write(const Relocate_info<size, big_endian>*, |
| 2719 | unsigned int sh_type, |
| 2720 | const unsigned char* prelocs, |
| 2721 | size_t reloc_count, |
| 2722 | Output_section*, |
| 2723 | Address output_offset, |
| 2724 | Output_file*); |
| 2725 | |
| 2726 | template<int sh_type> |
| 2727 | void |
| 2728 | incremental_relocs_write_reltype(const Relocate_info<size, big_endian>*, |
| 2729 | const unsigned char* prelocs, |
| 2730 | size_t reloc_count, |
| 2731 | Output_section*, |
| 2732 | Address output_offset, |
| 2733 | Output_file*); |
| 2734 | |
| 2735 | // A type shared by split_stack_adjust_reltype and find_functions. |
| 2736 | typedef std::map<section_offset_type, section_size_type> Function_offsets; |
| 2737 | |
| 2738 | // Check for -fsplit-stack routines calling non-split-stack routines. |
| 2739 | void |
| 2740 | split_stack_adjust(const Symbol_table*, const unsigned char* pshdrs, |
| 2741 | unsigned int sh_type, unsigned int shndx, |
| 2742 | const unsigned char* prelocs, size_t reloc_count, |
| 2743 | unsigned char* view, section_size_type view_size, |
| 2744 | Reloc_symbol_changes** reloc_map, |
| 2745 | const Sized_target<size, big_endian>* target); |
| 2746 | |
| 2747 | template<int sh_type> |
| 2748 | void |
| 2749 | split_stack_adjust_reltype(const Symbol_table*, const unsigned char* pshdrs, |
| 2750 | unsigned int shndx, const unsigned char* prelocs, |
| 2751 | size_t reloc_count, unsigned char* view, |
| 2752 | section_size_type view_size, |
| 2753 | Reloc_symbol_changes** reloc_map, |
| 2754 | const Sized_target<size, big_endian>* target); |
| 2755 | |
| 2756 | // Find all functions in a section. |
| 2757 | void |
| 2758 | find_functions(const unsigned char* pshdrs, unsigned int shndx, |
| 2759 | Function_offsets*); |
| 2760 | |
| 2761 | // Write out the local symbols. |
| 2762 | void |
| 2763 | write_local_symbols(Output_file*, |
| 2764 | const Stringpool_template<char>*, |
| 2765 | const Stringpool_template<char>*, |
| 2766 | Output_symtab_xindex*, |
| 2767 | Output_symtab_xindex*, |
| 2768 | off_t); |
| 2769 | |
| 2770 | // Record a mapping from discarded section SHNDX to the corresponding |
| 2771 | // kept section. |
| 2772 | void |
| 2773 | set_kept_comdat_section(unsigned int shndx, bool is_comdat, |
| 2774 | unsigned int symndx, uint64_t sh_size, |
| 2775 | Kept_section* kept_section) |
| 2776 | { |
| 2777 | Kept_comdat_section kept(sh_size, kept_section, symndx, is_comdat); |
| 2778 | this->kept_comdat_sections_.insert(std::make_pair(shndx, kept)); |
| 2779 | } |
| 2780 | |
| 2781 | // Find the kept section corresponding to the discarded section |
| 2782 | // SHNDX. Return true if found. |
| 2783 | bool |
| 2784 | get_kept_comdat_section(unsigned int shndx, bool* is_comdat, |
| 2785 | unsigned int *symndx, uint64_t* sh_size, |
| 2786 | Kept_section** kept_section) const |
| 2787 | { |
| 2788 | typename Kept_comdat_section_table::const_iterator p = |
| 2789 | this->kept_comdat_sections_.find(shndx); |
| 2790 | if (p == this->kept_comdat_sections_.end()) |
| 2791 | return false; |
| 2792 | *is_comdat = p->second.is_comdat; |
| 2793 | *symndx = p->second.symndx; |
| 2794 | *sh_size = p->second.sh_size; |
| 2795 | *kept_section = p->second.kept_section; |
| 2796 | return true; |
| 2797 | } |
| 2798 | |
| 2799 | // Compute final local symbol value. R_SYM is the local symbol index. |
| 2800 | // LV_IN points to a local symbol value containing the input value. |
| 2801 | // LV_OUT points to a local symbol value storing the final output value, |
| 2802 | // which must not be a merged symbol value since before calling this |
| 2803 | // method to avoid memory leak. RELOCATABLE indicates whether we are |
| 2804 | // linking a relocatable output. OUT_SECTIONS is an array of output |
| 2805 | // sections. OUT_OFFSETS is an array of offsets of the sections. SYMTAB |
| 2806 | // points to a symbol table. |
| 2807 | // |
| 2808 | // The method returns a status code at return. If the return status is |
| 2809 | // CFLV_OK, *LV_OUT contains the final value. If the return status is |
| 2810 | // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED, |
| 2811 | // *LV_OUT is not modified. |
| 2812 | inline Compute_final_local_value_status |
| 2813 | compute_final_local_value_internal(unsigned int r_sym, |
| 2814 | const Symbol_value<size>* lv_in, |
| 2815 | Symbol_value<size>* lv_out, |
| 2816 | bool relocatable, |
| 2817 | const Output_sections& out_sections, |
| 2818 | const std::vector<Address>& out_offsets, |
| 2819 | const Symbol_table* symtab); |
| 2820 | |
| 2821 | // The PLT offsets of local symbols. |
| 2822 | typedef Unordered_map<unsigned int, unsigned int> Local_plt_offsets; |
| 2823 | |
| 2824 | // Saved information for sections whose layout was deferred. |
| 2825 | struct Deferred_layout |
| 2826 | { |
| 2827 | static const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size; |
| 2828 | Deferred_layout(unsigned int shndx, const char* name, |
| 2829 | unsigned int sh_type, |
| 2830 | const unsigned char* pshdr, |
| 2831 | unsigned int reloc_shndx, unsigned int reloc_type) |
| 2832 | : name_(name), shndx_(shndx), reloc_shndx_(reloc_shndx), |
| 2833 | reloc_type_(reloc_type) |
| 2834 | { |
| 2835 | typename This::Shdr_write shdr(this->shdr_data_); |
| 2836 | memcpy(this->shdr_data_, pshdr, shdr_size); |
| 2837 | shdr.put_sh_type(sh_type); |
| 2838 | } |
| 2839 | std::string name_; |
| 2840 | unsigned int shndx_; |
| 2841 | unsigned int reloc_shndx_; |
| 2842 | unsigned int reloc_type_; |
| 2843 | unsigned char shdr_data_[shdr_size]; |
| 2844 | }; |
| 2845 | |
| 2846 | // General access to the ELF file. |
| 2847 | elfcpp::Elf_file<size, big_endian, Object> elf_file_; |
| 2848 | // Type of ELF file (ET_REL or ET_EXEC). ET_EXEC files are allowed |
| 2849 | // as input files only for the --just-symbols option. |
| 2850 | int e_type_; |
| 2851 | // Index of SHT_SYMTAB section. |
| 2852 | unsigned int symtab_shndx_; |
| 2853 | // The number of local symbols. |
| 2854 | unsigned int local_symbol_count_; |
| 2855 | // The number of local symbols which go into the output file. |
| 2856 | unsigned int output_local_symbol_count_; |
| 2857 | // The number of local symbols which go into the output file's dynamic |
| 2858 | // symbol table. |
| 2859 | unsigned int output_local_dynsym_count_; |
| 2860 | // The entries in the symbol table for the external symbols. |
| 2861 | Symbols symbols_; |
| 2862 | // Number of symbols defined in object file itself. |
| 2863 | size_t defined_count_; |
| 2864 | // File offset for local symbols (relative to start of symbol table). |
| 2865 | off_t local_symbol_offset_; |
| 2866 | // File offset for local dynamic symbols (absolute). |
| 2867 | off_t local_dynsym_offset_; |
| 2868 | // Values of local symbols. |
| 2869 | Local_values local_values_; |
| 2870 | // PLT offsets for local symbols. |
| 2871 | Local_plt_offsets local_plt_offsets_; |
| 2872 | // Table mapping discarded comdat sections to corresponding kept sections. |
| 2873 | Kept_comdat_section_table kept_comdat_sections_; |
| 2874 | // Whether this object has a GNU style .eh_frame section. |
| 2875 | bool has_eh_frame_; |
| 2876 | // True if the layout of this object was deferred, waiting for plugin |
| 2877 | // replacement files. |
| 2878 | bool is_deferred_layout_; |
| 2879 | // The list of sections whose layout was deferred. |
| 2880 | std::vector<Deferred_layout> deferred_layout_; |
| 2881 | // The list of relocation sections whose layout was deferred. |
| 2882 | std::vector<Deferred_layout> deferred_layout_relocs_; |
| 2883 | // Pointer to the list of output views; valid only during do_relocate(). |
| 2884 | const Views* output_views_; |
| 2885 | }; |
| 2886 | |
| 2887 | // A class to manage the list of all objects. |
| 2888 | |
| 2889 | class Input_objects |
| 2890 | { |
| 2891 | public: |
| 2892 | Input_objects() |
| 2893 | : relobj_list_(), dynobj_list_(), sonames_(), cref_(NULL) |
| 2894 | { } |
| 2895 | |
| 2896 | // The type of the list of input relocateable objects. |
| 2897 | typedef std::vector<Relobj*> Relobj_list; |
| 2898 | typedef Relobj_list::const_iterator Relobj_iterator; |
| 2899 | |
| 2900 | // The type of the list of input dynamic objects. |
| 2901 | typedef std::vector<Dynobj*> Dynobj_list; |
| 2902 | typedef Dynobj_list::const_iterator Dynobj_iterator; |
| 2903 | |
| 2904 | // Add an object to the list. Return true if all is well, or false |
| 2905 | // if this object should be ignored. |
| 2906 | bool |
| 2907 | add_object(Object*); |
| 2908 | |
| 2909 | // Start processing an archive. |
| 2910 | void |
| 2911 | archive_start(Archive*); |
| 2912 | |
| 2913 | // Stop processing an archive. |
| 2914 | void |
| 2915 | archive_stop(Archive*); |
| 2916 | |
| 2917 | // For each dynamic object, check whether we've seen all of its |
| 2918 | // explicit dependencies. |
| 2919 | void |
| 2920 | check_dynamic_dependencies() const; |
| 2921 | |
| 2922 | // Return whether an object was found in the system library |
| 2923 | // directory. |
| 2924 | bool |
| 2925 | found_in_system_library_directory(const Object*) const; |
| 2926 | |
| 2927 | // Print symbol counts. |
| 2928 | void |
| 2929 | print_symbol_counts(const Symbol_table*) const; |
| 2930 | |
| 2931 | // Print a cross reference table. |
| 2932 | void |
| 2933 | print_cref(const Symbol_table*, FILE*) const; |
| 2934 | |
| 2935 | // Iterate over all regular objects. |
| 2936 | |
| 2937 | Relobj_iterator |
| 2938 | relobj_begin() const |
| 2939 | { return this->relobj_list_.begin(); } |
| 2940 | |
| 2941 | Relobj_iterator |
| 2942 | relobj_end() const |
| 2943 | { return this->relobj_list_.end(); } |
| 2944 | |
| 2945 | // Iterate over all dynamic objects. |
| 2946 | |
| 2947 | Dynobj_iterator |
| 2948 | dynobj_begin() const |
| 2949 | { return this->dynobj_list_.begin(); } |
| 2950 | |
| 2951 | Dynobj_iterator |
| 2952 | dynobj_end() const |
| 2953 | { return this->dynobj_list_.end(); } |
| 2954 | |
| 2955 | // Return whether we have seen any dynamic objects. |
| 2956 | bool |
| 2957 | any_dynamic() const |
| 2958 | { return !this->dynobj_list_.empty(); } |
| 2959 | |
| 2960 | // Return the number of non dynamic objects. |
| 2961 | int |
| 2962 | number_of_relobjs() const |
| 2963 | { return this->relobj_list_.size(); } |
| 2964 | |
| 2965 | // Return the number of input objects. |
| 2966 | int |
| 2967 | number_of_input_objects() const |
| 2968 | { return this->relobj_list_.size() + this->dynobj_list_.size(); } |
| 2969 | |
| 2970 | private: |
| 2971 | Input_objects(const Input_objects&); |
| 2972 | Input_objects& operator=(const Input_objects&); |
| 2973 | |
| 2974 | // The list of ordinary objects included in the link. |
| 2975 | Relobj_list relobj_list_; |
| 2976 | // The list of dynamic objects included in the link. |
| 2977 | Dynobj_list dynobj_list_; |
| 2978 | // SONAMEs that we have seen. |
| 2979 | Unordered_map<std::string, Object*> sonames_; |
| 2980 | // Manage cross-references if requested. |
| 2981 | Cref* cref_; |
| 2982 | }; |
| 2983 | |
| 2984 | // Some of the information we pass to the relocation routines. We |
| 2985 | // group this together to avoid passing a dozen different arguments. |
| 2986 | |
| 2987 | template<int size, bool big_endian> |
| 2988 | struct Relocate_info |
| 2989 | { |
| 2990 | // Symbol table. |
| 2991 | const Symbol_table* symtab; |
| 2992 | // Layout. |
| 2993 | const Layout* layout; |
| 2994 | // Object being relocated. |
| 2995 | Sized_relobj_file<size, big_endian>* object; |
| 2996 | // Section index of relocation section. |
| 2997 | unsigned int reloc_shndx; |
| 2998 | // Section header of relocation section. |
| 2999 | const unsigned char* reloc_shdr; |
| 3000 | // Info about how relocs should be handled |
| 3001 | Relocatable_relocs* rr; |
| 3002 | // Section index of section being relocated. |
| 3003 | unsigned int data_shndx; |
| 3004 | // Section header of data section. |
| 3005 | const unsigned char* data_shdr; |
| 3006 | |
| 3007 | // Return a string showing the location of a relocation. This is |
| 3008 | // only used for error messages. |
| 3009 | std::string |
| 3010 | location(size_t relnum, off_t reloffset) const; |
| 3011 | }; |
| 3012 | |
| 3013 | // This is used to represent a section in an object and is used as the |
| 3014 | // key type for various section maps. |
| 3015 | typedef std::pair<Relobj*, unsigned int> Section_id; |
| 3016 | |
| 3017 | // This is similar to Section_id but is used when the section |
| 3018 | // pointers are const. |
| 3019 | typedef std::pair<const Relobj*, unsigned int> Const_section_id; |
| 3020 | |
| 3021 | // The hash value is based on the address of an object in memory during |
| 3022 | // linking. It is okay to use this for looking up sections but never use |
| 3023 | // this in an unordered container that we want to traverse in a repeatable |
| 3024 | // manner. |
| 3025 | |
| 3026 | struct Section_id_hash |
| 3027 | { |
| 3028 | size_t operator()(const Section_id& loc) const |
| 3029 | { return reinterpret_cast<uintptr_t>(loc.first) ^ loc.second; } |
| 3030 | }; |
| 3031 | |
| 3032 | struct Const_section_id_hash |
| 3033 | { |
| 3034 | size_t operator()(const Const_section_id& loc) const |
| 3035 | { return reinterpret_cast<uintptr_t>(loc.first) ^ loc.second; } |
| 3036 | }; |
| 3037 | |
| 3038 | // Return whether INPUT_FILE contains an ELF object start at file |
| 3039 | // offset OFFSET. This sets *START to point to a view of the start of |
| 3040 | // the file. It sets *READ_SIZE to the number of bytes in the view. |
| 3041 | |
| 3042 | extern bool |
| 3043 | is_elf_object(Input_file* input_file, off_t offset, |
| 3044 | const unsigned char** start, int* read_size); |
| 3045 | |
| 3046 | // Return an Object appropriate for the input file. P is BYTES long, |
| 3047 | // and holds the ELF header. If PUNCONFIGURED is not NULL, then if |
| 3048 | // this sees an object the linker is not configured to support, it |
| 3049 | // sets *PUNCONFIGURED to true and returns NULL without giving an |
| 3050 | // error message. |
| 3051 | |
| 3052 | extern Object* |
| 3053 | make_elf_object(const std::string& name, Input_file*, |
| 3054 | off_t offset, const unsigned char* p, |
| 3055 | section_offset_type bytes, bool* punconfigured); |
| 3056 | |
| 3057 | } // end namespace gold |
| 3058 | |
| 3059 | #endif // !defined(GOLD_OBJECT_H) |