| 1 | // script-sections.cc -- linker script SECTIONS for gold |
| 2 | |
| 3 | // Copyright 2008, 2009 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 | #include "gold.h" |
| 24 | |
| 25 | #include <cstring> |
| 26 | #include <algorithm> |
| 27 | #include <list> |
| 28 | #include <map> |
| 29 | #include <string> |
| 30 | #include <vector> |
| 31 | #include <fnmatch.h> |
| 32 | |
| 33 | #include "parameters.h" |
| 34 | #include "object.h" |
| 35 | #include "layout.h" |
| 36 | #include "output.h" |
| 37 | #include "script-c.h" |
| 38 | #include "script.h" |
| 39 | #include "script-sections.h" |
| 40 | |
| 41 | // Support for the SECTIONS clause in linker scripts. |
| 42 | |
| 43 | namespace gold |
| 44 | { |
| 45 | |
| 46 | // Manage orphan sections. This is intended to be largely compatible |
| 47 | // with the GNU linker. The Linux kernel implicitly relies on |
| 48 | // something similar to the GNU linker's orphan placement. We |
| 49 | // originally used a simpler scheme here, but it caused the kernel |
| 50 | // build to fail, and was also rather inefficient. |
| 51 | |
| 52 | class Orphan_section_placement |
| 53 | { |
| 54 | private: |
| 55 | typedef Script_sections::Elements_iterator Elements_iterator; |
| 56 | |
| 57 | public: |
| 58 | Orphan_section_placement(); |
| 59 | |
| 60 | // Handle an output section during initialization of this mapping. |
| 61 | void |
| 62 | output_section_init(const std::string& name, Output_section*, |
| 63 | Elements_iterator location); |
| 64 | |
| 65 | // Initialize the last location. |
| 66 | void |
| 67 | last_init(Elements_iterator location); |
| 68 | |
| 69 | // Set *PWHERE to the address of an iterator pointing to the |
| 70 | // location to use for an orphan section. Return true if the |
| 71 | // iterator has a value, false otherwise. |
| 72 | bool |
| 73 | find_place(Output_section*, Elements_iterator** pwhere); |
| 74 | |
| 75 | // Return the iterator being used for sections at the very end of |
| 76 | // the linker script. |
| 77 | Elements_iterator |
| 78 | last_place() const; |
| 79 | |
| 80 | private: |
| 81 | // The places that we specifically recognize. This list is copied |
| 82 | // from the GNU linker. |
| 83 | enum Place_index |
| 84 | { |
| 85 | PLACE_TEXT, |
| 86 | PLACE_RODATA, |
| 87 | PLACE_DATA, |
| 88 | PLACE_BSS, |
| 89 | PLACE_REL, |
| 90 | PLACE_INTERP, |
| 91 | PLACE_NONALLOC, |
| 92 | PLACE_LAST, |
| 93 | PLACE_MAX |
| 94 | }; |
| 95 | |
| 96 | // The information we keep for a specific place. |
| 97 | struct Place |
| 98 | { |
| 99 | // The name of sections for this place. |
| 100 | const char* name; |
| 101 | // Whether we have a location for this place. |
| 102 | bool have_location; |
| 103 | // The iterator for this place. |
| 104 | Elements_iterator location; |
| 105 | }; |
| 106 | |
| 107 | // Initialize one place element. |
| 108 | void |
| 109 | initialize_place(Place_index, const char*); |
| 110 | |
| 111 | // The places. |
| 112 | Place places_[PLACE_MAX]; |
| 113 | // True if this is the first call to output_section_init. |
| 114 | bool first_init_; |
| 115 | }; |
| 116 | |
| 117 | // Initialize Orphan_section_placement. |
| 118 | |
| 119 | Orphan_section_placement::Orphan_section_placement() |
| 120 | : first_init_(true) |
| 121 | { |
| 122 | this->initialize_place(PLACE_TEXT, ".text"); |
| 123 | this->initialize_place(PLACE_RODATA, ".rodata"); |
| 124 | this->initialize_place(PLACE_DATA, ".data"); |
| 125 | this->initialize_place(PLACE_BSS, ".bss"); |
| 126 | this->initialize_place(PLACE_REL, NULL); |
| 127 | this->initialize_place(PLACE_INTERP, ".interp"); |
| 128 | this->initialize_place(PLACE_NONALLOC, NULL); |
| 129 | this->initialize_place(PLACE_LAST, NULL); |
| 130 | } |
| 131 | |
| 132 | // Initialize one place element. |
| 133 | |
| 134 | void |
| 135 | Orphan_section_placement::initialize_place(Place_index index, const char* name) |
| 136 | { |
| 137 | this->places_[index].name = name; |
| 138 | this->places_[index].have_location = false; |
| 139 | } |
| 140 | |
| 141 | // While initializing the Orphan_section_placement information, this |
| 142 | // is called once for each output section named in the linker script. |
| 143 | // If we found an output section during the link, it will be passed in |
| 144 | // OS. |
| 145 | |
| 146 | void |
| 147 | Orphan_section_placement::output_section_init(const std::string& name, |
| 148 | Output_section* os, |
| 149 | Elements_iterator location) |
| 150 | { |
| 151 | bool first_init = this->first_init_; |
| 152 | this->first_init_ = false; |
| 153 | |
| 154 | for (int i = 0; i < PLACE_MAX; ++i) |
| 155 | { |
| 156 | if (this->places_[i].name != NULL && this->places_[i].name == name) |
| 157 | { |
| 158 | if (this->places_[i].have_location) |
| 159 | { |
| 160 | // We have already seen a section with this name. |
| 161 | return; |
| 162 | } |
| 163 | |
| 164 | this->places_[i].location = location; |
| 165 | this->places_[i].have_location = true; |
| 166 | |
| 167 | // If we just found the .bss section, restart the search for |
| 168 | // an unallocated section. This follows the GNU linker's |
| 169 | // behaviour. |
| 170 | if (i == PLACE_BSS) |
| 171 | this->places_[PLACE_NONALLOC].have_location = false; |
| 172 | |
| 173 | return; |
| 174 | } |
| 175 | } |
| 176 | |
| 177 | // Relocation sections. |
| 178 | if (!this->places_[PLACE_REL].have_location |
| 179 | && os != NULL |
| 180 | && (os->type() == elfcpp::SHT_REL || os->type() == elfcpp::SHT_RELA) |
| 181 | && (os->flags() & elfcpp::SHF_ALLOC) != 0) |
| 182 | { |
| 183 | this->places_[PLACE_REL].location = location; |
| 184 | this->places_[PLACE_REL].have_location = true; |
| 185 | } |
| 186 | |
| 187 | // We find the location for unallocated sections by finding the |
| 188 | // first debugging or comment section after the BSS section (if |
| 189 | // there is one). |
| 190 | if (!this->places_[PLACE_NONALLOC].have_location |
| 191 | && (name == ".comment" || Layout::is_debug_info_section(name.c_str()))) |
| 192 | { |
| 193 | // We add orphan sections after the location in PLACES_. We |
| 194 | // want to store unallocated sections before LOCATION. If this |
| 195 | // is the very first section, we can't use it. |
| 196 | if (!first_init) |
| 197 | { |
| 198 | --location; |
| 199 | this->places_[PLACE_NONALLOC].location = location; |
| 200 | this->places_[PLACE_NONALLOC].have_location = true; |
| 201 | } |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | // Initialize the last location. |
| 206 | |
| 207 | void |
| 208 | Orphan_section_placement::last_init(Elements_iterator location) |
| 209 | { |
| 210 | this->places_[PLACE_LAST].location = location; |
| 211 | this->places_[PLACE_LAST].have_location = true; |
| 212 | } |
| 213 | |
| 214 | // Set *PWHERE to the address of an iterator pointing to the location |
| 215 | // to use for an orphan section. Return true if the iterator has a |
| 216 | // value, false otherwise. |
| 217 | |
| 218 | bool |
| 219 | Orphan_section_placement::find_place(Output_section* os, |
| 220 | Elements_iterator** pwhere) |
| 221 | { |
| 222 | // Figure out where OS should go. This is based on the GNU linker |
| 223 | // code. FIXME: The GNU linker handles small data sections |
| 224 | // specially, but we don't. |
| 225 | elfcpp::Elf_Word type = os->type(); |
| 226 | elfcpp::Elf_Xword flags = os->flags(); |
| 227 | Place_index index; |
| 228 | if ((flags & elfcpp::SHF_ALLOC) == 0 |
| 229 | && !Layout::is_debug_info_section(os->name())) |
| 230 | index = PLACE_NONALLOC; |
| 231 | else if ((flags & elfcpp::SHF_ALLOC) == 0) |
| 232 | index = PLACE_LAST; |
| 233 | else if (type == elfcpp::SHT_NOTE) |
| 234 | index = PLACE_INTERP; |
| 235 | else if (type == elfcpp::SHT_NOBITS) |
| 236 | index = PLACE_BSS; |
| 237 | else if ((flags & elfcpp::SHF_WRITE) != 0) |
| 238 | index = PLACE_DATA; |
| 239 | else if (type == elfcpp::SHT_REL || type == elfcpp::SHT_RELA) |
| 240 | index = PLACE_REL; |
| 241 | else if ((flags & elfcpp::SHF_EXECINSTR) == 0) |
| 242 | index = PLACE_RODATA; |
| 243 | else |
| 244 | index = PLACE_TEXT; |
| 245 | |
| 246 | // If we don't have a location yet, try to find one based on a |
| 247 | // plausible ordering of sections. |
| 248 | if (!this->places_[index].have_location) |
| 249 | { |
| 250 | Place_index follow; |
| 251 | switch (index) |
| 252 | { |
| 253 | default: |
| 254 | follow = PLACE_MAX; |
| 255 | break; |
| 256 | case PLACE_RODATA: |
| 257 | follow = PLACE_TEXT; |
| 258 | break; |
| 259 | case PLACE_BSS: |
| 260 | follow = PLACE_DATA; |
| 261 | break; |
| 262 | case PLACE_REL: |
| 263 | follow = PLACE_TEXT; |
| 264 | break; |
| 265 | case PLACE_INTERP: |
| 266 | follow = PLACE_TEXT; |
| 267 | break; |
| 268 | } |
| 269 | if (follow != PLACE_MAX && this->places_[follow].have_location) |
| 270 | { |
| 271 | // Set the location of INDEX to the location of FOLLOW. The |
| 272 | // location of INDEX will then be incremented by the caller, |
| 273 | // so anything in INDEX will continue to be after anything |
| 274 | // in FOLLOW. |
| 275 | this->places_[index].location = this->places_[follow].location; |
| 276 | this->places_[index].have_location = true; |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | *pwhere = &this->places_[index].location; |
| 281 | bool ret = this->places_[index].have_location; |
| 282 | |
| 283 | // The caller will set the location. |
| 284 | this->places_[index].have_location = true; |
| 285 | |
| 286 | return ret; |
| 287 | } |
| 288 | |
| 289 | // Return the iterator being used for sections at the very end of the |
| 290 | // linker script. |
| 291 | |
| 292 | Orphan_section_placement::Elements_iterator |
| 293 | Orphan_section_placement::last_place() const |
| 294 | { |
| 295 | gold_assert(this->places_[PLACE_LAST].have_location); |
| 296 | return this->places_[PLACE_LAST].location; |
| 297 | } |
| 298 | |
| 299 | // An element in a SECTIONS clause. |
| 300 | |
| 301 | class Sections_element |
| 302 | { |
| 303 | public: |
| 304 | Sections_element() |
| 305 | { } |
| 306 | |
| 307 | virtual ~Sections_element() |
| 308 | { } |
| 309 | |
| 310 | // Return whether an output section is relro. |
| 311 | virtual bool |
| 312 | is_relro() const |
| 313 | { return false; } |
| 314 | |
| 315 | // Record that an output section is relro. |
| 316 | virtual void |
| 317 | set_is_relro() |
| 318 | { } |
| 319 | |
| 320 | // Create any required output sections. The only real |
| 321 | // implementation is in Output_section_definition. |
| 322 | virtual void |
| 323 | create_sections(Layout*) |
| 324 | { } |
| 325 | |
| 326 | // Add any symbol being defined to the symbol table. |
| 327 | virtual void |
| 328 | add_symbols_to_table(Symbol_table*) |
| 329 | { } |
| 330 | |
| 331 | // Finalize symbols and check assertions. |
| 332 | virtual void |
| 333 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*) |
| 334 | { } |
| 335 | |
| 336 | // Return the output section name to use for an input file name and |
| 337 | // section name. This only real implementation is in |
| 338 | // Output_section_definition. |
| 339 | virtual const char* |
| 340 | output_section_name(const char*, const char*, Output_section***) |
| 341 | { return NULL; } |
| 342 | |
| 343 | // Initialize OSP with an output section. |
| 344 | virtual void |
| 345 | orphan_section_init(Orphan_section_placement*, |
| 346 | Script_sections::Elements_iterator) |
| 347 | { } |
| 348 | |
| 349 | // Set section addresses. This includes applying assignments if the |
| 350 | // the expression is an absolute value. |
| 351 | virtual void |
| 352 | set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*) |
| 353 | { } |
| 354 | |
| 355 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 356 | // this section is constrained, and the input sections do not match, |
| 357 | // return the constraint, and set *POSD. |
| 358 | virtual Section_constraint |
| 359 | check_constraint(Output_section_definition**) |
| 360 | { return CONSTRAINT_NONE; } |
| 361 | |
| 362 | // See if this is the alternate output section for a constrained |
| 363 | // output section. If it is, transfer the Output_section and return |
| 364 | // true. Otherwise return false. |
| 365 | virtual bool |
| 366 | alternate_constraint(Output_section_definition*, Section_constraint) |
| 367 | { return false; } |
| 368 | |
| 369 | // Get the list of segments to use for an allocated section when |
| 370 | // using a PHDRS clause. If this is an allocated section, return |
| 371 | // the Output_section, and set *PHDRS_LIST (the first parameter) to |
| 372 | // the list of PHDRS to which it should be attached. If the PHDRS |
| 373 | // were not specified, don't change *PHDRS_LIST. When not returning |
| 374 | // NULL, set *ORPHAN (the second parameter) according to whether |
| 375 | // this is an orphan section--one that is not mentioned in the |
| 376 | // linker script. |
| 377 | virtual Output_section* |
| 378 | allocate_to_segment(String_list**, bool*) |
| 379 | { return NULL; } |
| 380 | |
| 381 | // Look for an output section by name and return the address, the |
| 382 | // load address, the alignment, and the size. This is used when an |
| 383 | // expression refers to an output section which was not actually |
| 384 | // created. This returns true if the section was found, false |
| 385 | // otherwise. The only real definition is for |
| 386 | // Output_section_definition. |
| 387 | virtual bool |
| 388 | get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| 389 | uint64_t*) const |
| 390 | { return false; } |
| 391 | |
| 392 | // Return the associated Output_section if there is one. |
| 393 | virtual Output_section* |
| 394 | get_output_section() const |
| 395 | { return NULL; } |
| 396 | |
| 397 | // Print the element for debugging purposes. |
| 398 | virtual void |
| 399 | print(FILE* f) const = 0; |
| 400 | }; |
| 401 | |
| 402 | // An assignment in a SECTIONS clause outside of an output section. |
| 403 | |
| 404 | class Sections_element_assignment : public Sections_element |
| 405 | { |
| 406 | public: |
| 407 | Sections_element_assignment(const char* name, size_t namelen, |
| 408 | Expression* val, bool provide, bool hidden) |
| 409 | : assignment_(name, namelen, val, provide, hidden) |
| 410 | { } |
| 411 | |
| 412 | // Add the symbol to the symbol table. |
| 413 | void |
| 414 | add_symbols_to_table(Symbol_table* symtab) |
| 415 | { this->assignment_.add_to_table(symtab); } |
| 416 | |
| 417 | // Finalize the symbol. |
| 418 | void |
| 419 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 420 | uint64_t* dot_value) |
| 421 | { |
| 422 | this->assignment_.finalize_with_dot(symtab, layout, *dot_value, NULL); |
| 423 | } |
| 424 | |
| 425 | // Set the section address. There is no section here, but if the |
| 426 | // value is absolute, we set the symbol. This permits us to use |
| 427 | // absolute symbols when setting dot. |
| 428 | void |
| 429 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 430 | uint64_t* dot_value, uint64_t*) |
| 431 | { |
| 432 | this->assignment_.set_if_absolute(symtab, layout, true, *dot_value); |
| 433 | } |
| 434 | |
| 435 | // Print for debugging. |
| 436 | void |
| 437 | print(FILE* f) const |
| 438 | { |
| 439 | fprintf(f, " "); |
| 440 | this->assignment_.print(f); |
| 441 | } |
| 442 | |
| 443 | private: |
| 444 | Symbol_assignment assignment_; |
| 445 | }; |
| 446 | |
| 447 | // An assignment to the dot symbol in a SECTIONS clause outside of an |
| 448 | // output section. |
| 449 | |
| 450 | class Sections_element_dot_assignment : public Sections_element |
| 451 | { |
| 452 | public: |
| 453 | Sections_element_dot_assignment(Expression* val) |
| 454 | : val_(val) |
| 455 | { } |
| 456 | |
| 457 | // Finalize the symbol. |
| 458 | void |
| 459 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 460 | uint64_t* dot_value) |
| 461 | { |
| 462 | // We ignore the section of the result because outside of an |
| 463 | // output section definition the dot symbol is always considered |
| 464 | // to be absolute. |
| 465 | Output_section* dummy; |
| 466 | *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| 467 | NULL, &dummy); |
| 468 | } |
| 469 | |
| 470 | // Update the dot symbol while setting section addresses. |
| 471 | void |
| 472 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 473 | uint64_t* dot_value, uint64_t* load_address) |
| 474 | { |
| 475 | Output_section* dummy; |
| 476 | *dot_value = this->val_->eval_with_dot(symtab, layout, false, *dot_value, |
| 477 | NULL, &dummy); |
| 478 | *load_address = *dot_value; |
| 479 | } |
| 480 | |
| 481 | // Print for debugging. |
| 482 | void |
| 483 | print(FILE* f) const |
| 484 | { |
| 485 | fprintf(f, " . = "); |
| 486 | this->val_->print(f); |
| 487 | fprintf(f, "\n"); |
| 488 | } |
| 489 | |
| 490 | private: |
| 491 | Expression* val_; |
| 492 | }; |
| 493 | |
| 494 | // An assertion in a SECTIONS clause outside of an output section. |
| 495 | |
| 496 | class Sections_element_assertion : public Sections_element |
| 497 | { |
| 498 | public: |
| 499 | Sections_element_assertion(Expression* check, const char* message, |
| 500 | size_t messagelen) |
| 501 | : assertion_(check, message, messagelen) |
| 502 | { } |
| 503 | |
| 504 | // Check the assertion. |
| 505 | void |
| 506 | finalize_symbols(Symbol_table* symtab, const Layout* layout, uint64_t*) |
| 507 | { this->assertion_.check(symtab, layout); } |
| 508 | |
| 509 | // Print for debugging. |
| 510 | void |
| 511 | print(FILE* f) const |
| 512 | { |
| 513 | fprintf(f, " "); |
| 514 | this->assertion_.print(f); |
| 515 | } |
| 516 | |
| 517 | private: |
| 518 | Script_assertion assertion_; |
| 519 | }; |
| 520 | |
| 521 | // An element in an output section in a SECTIONS clause. |
| 522 | |
| 523 | class Output_section_element |
| 524 | { |
| 525 | public: |
| 526 | // A list of input sections. |
| 527 | typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list; |
| 528 | |
| 529 | Output_section_element() |
| 530 | { } |
| 531 | |
| 532 | virtual ~Output_section_element() |
| 533 | { } |
| 534 | |
| 535 | // Return whether this element requires an output section to exist. |
| 536 | virtual bool |
| 537 | needs_output_section() const |
| 538 | { return false; } |
| 539 | |
| 540 | // Add any symbol being defined to the symbol table. |
| 541 | virtual void |
| 542 | add_symbols_to_table(Symbol_table*) |
| 543 | { } |
| 544 | |
| 545 | // Finalize symbols and check assertions. |
| 546 | virtual void |
| 547 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*, Output_section**) |
| 548 | { } |
| 549 | |
| 550 | // Return whether this element matches FILE_NAME and SECTION_NAME. |
| 551 | // The only real implementation is in Output_section_element_input. |
| 552 | virtual bool |
| 553 | match_name(const char*, const char*) const |
| 554 | { return false; } |
| 555 | |
| 556 | // Set section addresses. This includes applying assignments if the |
| 557 | // the expression is an absolute value. |
| 558 | virtual void |
| 559 | set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| 560 | uint64_t*, Output_section**, std::string*, |
| 561 | Input_section_list*) |
| 562 | { } |
| 563 | |
| 564 | // Print the element for debugging purposes. |
| 565 | virtual void |
| 566 | print(FILE* f) const = 0; |
| 567 | |
| 568 | protected: |
| 569 | // Return a fill string that is LENGTH bytes long, filling it with |
| 570 | // FILL. |
| 571 | std::string |
| 572 | get_fill_string(const std::string* fill, section_size_type length) const; |
| 573 | }; |
| 574 | |
| 575 | std::string |
| 576 | Output_section_element::get_fill_string(const std::string* fill, |
| 577 | section_size_type length) const |
| 578 | { |
| 579 | std::string this_fill; |
| 580 | this_fill.reserve(length); |
| 581 | while (this_fill.length() + fill->length() <= length) |
| 582 | this_fill += *fill; |
| 583 | if (this_fill.length() < length) |
| 584 | this_fill.append(*fill, 0, length - this_fill.length()); |
| 585 | return this_fill; |
| 586 | } |
| 587 | |
| 588 | // A symbol assignment in an output section. |
| 589 | |
| 590 | class Output_section_element_assignment : public Output_section_element |
| 591 | { |
| 592 | public: |
| 593 | Output_section_element_assignment(const char* name, size_t namelen, |
| 594 | Expression* val, bool provide, |
| 595 | bool hidden) |
| 596 | : assignment_(name, namelen, val, provide, hidden) |
| 597 | { } |
| 598 | |
| 599 | // Add the symbol to the symbol table. |
| 600 | void |
| 601 | add_symbols_to_table(Symbol_table* symtab) |
| 602 | { this->assignment_.add_to_table(symtab); } |
| 603 | |
| 604 | // Finalize the symbol. |
| 605 | void |
| 606 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 607 | uint64_t* dot_value, Output_section** dot_section) |
| 608 | { |
| 609 | this->assignment_.finalize_with_dot(symtab, layout, *dot_value, |
| 610 | *dot_section); |
| 611 | } |
| 612 | |
| 613 | // Set the section address. There is no section here, but if the |
| 614 | // value is absolute, we set the symbol. This permits us to use |
| 615 | // absolute symbols when setting dot. |
| 616 | void |
| 617 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 618 | uint64_t, uint64_t* dot_value, Output_section**, |
| 619 | std::string*, Input_section_list*) |
| 620 | { |
| 621 | this->assignment_.set_if_absolute(symtab, layout, true, *dot_value); |
| 622 | } |
| 623 | |
| 624 | // Print for debugging. |
| 625 | void |
| 626 | print(FILE* f) const |
| 627 | { |
| 628 | fprintf(f, " "); |
| 629 | this->assignment_.print(f); |
| 630 | } |
| 631 | |
| 632 | private: |
| 633 | Symbol_assignment assignment_; |
| 634 | }; |
| 635 | |
| 636 | // An assignment to the dot symbol in an output section. |
| 637 | |
| 638 | class Output_section_element_dot_assignment : public Output_section_element |
| 639 | { |
| 640 | public: |
| 641 | Output_section_element_dot_assignment(Expression* val) |
| 642 | : val_(val) |
| 643 | { } |
| 644 | |
| 645 | // Finalize the symbol. |
| 646 | void |
| 647 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 648 | uint64_t* dot_value, Output_section** dot_section) |
| 649 | { |
| 650 | *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| 651 | *dot_section, dot_section); |
| 652 | } |
| 653 | |
| 654 | // Update the dot symbol while setting section addresses. |
| 655 | void |
| 656 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 657 | uint64_t, uint64_t* dot_value, Output_section**, |
| 658 | std::string*, Input_section_list*); |
| 659 | |
| 660 | // Print for debugging. |
| 661 | void |
| 662 | print(FILE* f) const |
| 663 | { |
| 664 | fprintf(f, " . = "); |
| 665 | this->val_->print(f); |
| 666 | fprintf(f, "\n"); |
| 667 | } |
| 668 | |
| 669 | private: |
| 670 | Expression* val_; |
| 671 | }; |
| 672 | |
| 673 | // Update the dot symbol while setting section addresses. |
| 674 | |
| 675 | void |
| 676 | Output_section_element_dot_assignment::set_section_addresses( |
| 677 | Symbol_table* symtab, |
| 678 | Layout* layout, |
| 679 | Output_section* output_section, |
| 680 | uint64_t, |
| 681 | uint64_t* dot_value, |
| 682 | Output_section** dot_section, |
| 683 | std::string* fill, |
| 684 | Input_section_list*) |
| 685 | { |
| 686 | uint64_t next_dot = this->val_->eval_with_dot(symtab, layout, false, |
| 687 | *dot_value, *dot_section, |
| 688 | dot_section); |
| 689 | if (next_dot < *dot_value) |
| 690 | gold_error(_("dot may not move backward")); |
| 691 | if (next_dot > *dot_value && output_section != NULL) |
| 692 | { |
| 693 | section_size_type length = convert_to_section_size_type(next_dot |
| 694 | - *dot_value); |
| 695 | Output_section_data* posd; |
| 696 | if (fill->empty()) |
| 697 | posd = new Output_data_zero_fill(length, 0); |
| 698 | else |
| 699 | { |
| 700 | std::string this_fill = this->get_fill_string(fill, length); |
| 701 | posd = new Output_data_const(this_fill, 0); |
| 702 | } |
| 703 | output_section->add_output_section_data(posd); |
| 704 | } |
| 705 | *dot_value = next_dot; |
| 706 | } |
| 707 | |
| 708 | // An assertion in an output section. |
| 709 | |
| 710 | class Output_section_element_assertion : public Output_section_element |
| 711 | { |
| 712 | public: |
| 713 | Output_section_element_assertion(Expression* check, const char* message, |
| 714 | size_t messagelen) |
| 715 | : assertion_(check, message, messagelen) |
| 716 | { } |
| 717 | |
| 718 | void |
| 719 | print(FILE* f) const |
| 720 | { |
| 721 | fprintf(f, " "); |
| 722 | this->assertion_.print(f); |
| 723 | } |
| 724 | |
| 725 | private: |
| 726 | Script_assertion assertion_; |
| 727 | }; |
| 728 | |
| 729 | // We use a special instance of Output_section_data to handle BYTE, |
| 730 | // SHORT, etc. This permits forward references to symbols in the |
| 731 | // expressions. |
| 732 | |
| 733 | class Output_data_expression : public Output_section_data |
| 734 | { |
| 735 | public: |
| 736 | Output_data_expression(int size, bool is_signed, Expression* val, |
| 737 | const Symbol_table* symtab, const Layout* layout, |
| 738 | uint64_t dot_value, Output_section* dot_section) |
| 739 | : Output_section_data(size, 0), |
| 740 | is_signed_(is_signed), val_(val), symtab_(symtab), |
| 741 | layout_(layout), dot_value_(dot_value), dot_section_(dot_section) |
| 742 | { } |
| 743 | |
| 744 | protected: |
| 745 | // Write the data to the output file. |
| 746 | void |
| 747 | do_write(Output_file*); |
| 748 | |
| 749 | // Write the data to a buffer. |
| 750 | void |
| 751 | do_write_to_buffer(unsigned char*); |
| 752 | |
| 753 | // Write to a map file. |
| 754 | void |
| 755 | do_print_to_mapfile(Mapfile* mapfile) const |
| 756 | { mapfile->print_output_data(this, _("** expression")); } |
| 757 | |
| 758 | private: |
| 759 | template<bool big_endian> |
| 760 | void |
| 761 | endian_write_to_buffer(uint64_t, unsigned char*); |
| 762 | |
| 763 | bool is_signed_; |
| 764 | Expression* val_; |
| 765 | const Symbol_table* symtab_; |
| 766 | const Layout* layout_; |
| 767 | uint64_t dot_value_; |
| 768 | Output_section* dot_section_; |
| 769 | }; |
| 770 | |
| 771 | // Write the data element to the output file. |
| 772 | |
| 773 | void |
| 774 | Output_data_expression::do_write(Output_file* of) |
| 775 | { |
| 776 | unsigned char* view = of->get_output_view(this->offset(), this->data_size()); |
| 777 | this->write_to_buffer(view); |
| 778 | of->write_output_view(this->offset(), this->data_size(), view); |
| 779 | } |
| 780 | |
| 781 | // Write the data element to a buffer. |
| 782 | |
| 783 | void |
| 784 | Output_data_expression::do_write_to_buffer(unsigned char* buf) |
| 785 | { |
| 786 | Output_section* dummy; |
| 787 | uint64_t val = this->val_->eval_with_dot(this->symtab_, this->layout_, |
| 788 | true, this->dot_value_, |
| 789 | this->dot_section_, &dummy); |
| 790 | |
| 791 | if (parameters->target().is_big_endian()) |
| 792 | this->endian_write_to_buffer<true>(val, buf); |
| 793 | else |
| 794 | this->endian_write_to_buffer<false>(val, buf); |
| 795 | } |
| 796 | |
| 797 | template<bool big_endian> |
| 798 | void |
| 799 | Output_data_expression::endian_write_to_buffer(uint64_t val, |
| 800 | unsigned char* buf) |
| 801 | { |
| 802 | switch (this->data_size()) |
| 803 | { |
| 804 | case 1: |
| 805 | elfcpp::Swap_unaligned<8, big_endian>::writeval(buf, val); |
| 806 | break; |
| 807 | case 2: |
| 808 | elfcpp::Swap_unaligned<16, big_endian>::writeval(buf, val); |
| 809 | break; |
| 810 | case 4: |
| 811 | elfcpp::Swap_unaligned<32, big_endian>::writeval(buf, val); |
| 812 | break; |
| 813 | case 8: |
| 814 | if (parameters->target().get_size() == 32) |
| 815 | { |
| 816 | val &= 0xffffffff; |
| 817 | if (this->is_signed_ && (val & 0x80000000) != 0) |
| 818 | val |= 0xffffffff00000000LL; |
| 819 | } |
| 820 | elfcpp::Swap_unaligned<64, big_endian>::writeval(buf, val); |
| 821 | break; |
| 822 | default: |
| 823 | gold_unreachable(); |
| 824 | } |
| 825 | } |
| 826 | |
| 827 | // A data item in an output section. |
| 828 | |
| 829 | class Output_section_element_data : public Output_section_element |
| 830 | { |
| 831 | public: |
| 832 | Output_section_element_data(int size, bool is_signed, Expression* val) |
| 833 | : size_(size), is_signed_(is_signed), val_(val) |
| 834 | { } |
| 835 | |
| 836 | // If there is a data item, then we must create an output section. |
| 837 | bool |
| 838 | needs_output_section() const |
| 839 | { return true; } |
| 840 | |
| 841 | // Finalize symbols--we just need to update dot. |
| 842 | void |
| 843 | finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| 844 | Output_section**) |
| 845 | { *dot_value += this->size_; } |
| 846 | |
| 847 | // Store the value in the section. |
| 848 | void |
| 849 | set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| 850 | uint64_t* dot_value, Output_section**, std::string*, |
| 851 | Input_section_list*); |
| 852 | |
| 853 | // Print for debugging. |
| 854 | void |
| 855 | print(FILE*) const; |
| 856 | |
| 857 | private: |
| 858 | // The size in bytes. |
| 859 | int size_; |
| 860 | // Whether the value is signed. |
| 861 | bool is_signed_; |
| 862 | // The value. |
| 863 | Expression* val_; |
| 864 | }; |
| 865 | |
| 866 | // Store the value in the section. |
| 867 | |
| 868 | void |
| 869 | Output_section_element_data::set_section_addresses( |
| 870 | Symbol_table* symtab, |
| 871 | Layout* layout, |
| 872 | Output_section* os, |
| 873 | uint64_t, |
| 874 | uint64_t* dot_value, |
| 875 | Output_section** dot_section, |
| 876 | std::string*, |
| 877 | Input_section_list*) |
| 878 | { |
| 879 | gold_assert(os != NULL); |
| 880 | os->add_output_section_data(new Output_data_expression(this->size_, |
| 881 | this->is_signed_, |
| 882 | this->val_, |
| 883 | symtab, |
| 884 | layout, |
| 885 | *dot_value, |
| 886 | *dot_section)); |
| 887 | *dot_value += this->size_; |
| 888 | } |
| 889 | |
| 890 | // Print for debugging. |
| 891 | |
| 892 | void |
| 893 | Output_section_element_data::print(FILE* f) const |
| 894 | { |
| 895 | const char* s; |
| 896 | switch (this->size_) |
| 897 | { |
| 898 | case 1: |
| 899 | s = "BYTE"; |
| 900 | break; |
| 901 | case 2: |
| 902 | s = "SHORT"; |
| 903 | break; |
| 904 | case 4: |
| 905 | s = "LONG"; |
| 906 | break; |
| 907 | case 8: |
| 908 | if (this->is_signed_) |
| 909 | s = "SQUAD"; |
| 910 | else |
| 911 | s = "QUAD"; |
| 912 | break; |
| 913 | default: |
| 914 | gold_unreachable(); |
| 915 | } |
| 916 | fprintf(f, " %s(", s); |
| 917 | this->val_->print(f); |
| 918 | fprintf(f, ")\n"); |
| 919 | } |
| 920 | |
| 921 | // A fill value setting in an output section. |
| 922 | |
| 923 | class Output_section_element_fill : public Output_section_element |
| 924 | { |
| 925 | public: |
| 926 | Output_section_element_fill(Expression* val) |
| 927 | : val_(val) |
| 928 | { } |
| 929 | |
| 930 | // Update the fill value while setting section addresses. |
| 931 | void |
| 932 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 933 | uint64_t, uint64_t* dot_value, |
| 934 | Output_section** dot_section, |
| 935 | std::string* fill, Input_section_list*) |
| 936 | { |
| 937 | Output_section* fill_section; |
| 938 | uint64_t fill_val = this->val_->eval_with_dot(symtab, layout, false, |
| 939 | *dot_value, *dot_section, |
| 940 | &fill_section); |
| 941 | if (fill_section != NULL) |
| 942 | gold_warning(_("fill value is not absolute")); |
| 943 | // FIXME: The GNU linker supports fill values of arbitrary length. |
| 944 | unsigned char fill_buff[4]; |
| 945 | elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| 946 | fill->assign(reinterpret_cast<char*>(fill_buff), 4); |
| 947 | } |
| 948 | |
| 949 | // Print for debugging. |
| 950 | void |
| 951 | print(FILE* f) const |
| 952 | { |
| 953 | fprintf(f, " FILL("); |
| 954 | this->val_->print(f); |
| 955 | fprintf(f, ")\n"); |
| 956 | } |
| 957 | |
| 958 | private: |
| 959 | // The new fill value. |
| 960 | Expression* val_; |
| 961 | }; |
| 962 | |
| 963 | // Return whether STRING contains a wildcard character. This is used |
| 964 | // to speed up matching. |
| 965 | |
| 966 | static inline bool |
| 967 | is_wildcard_string(const std::string& s) |
| 968 | { |
| 969 | return strpbrk(s.c_str(), "?*[") != NULL; |
| 970 | } |
| 971 | |
| 972 | // An input section specification in an output section |
| 973 | |
| 974 | class Output_section_element_input : public Output_section_element |
| 975 | { |
| 976 | public: |
| 977 | Output_section_element_input(const Input_section_spec* spec, bool keep); |
| 978 | |
| 979 | // Finalize symbols--just update the value of the dot symbol. |
| 980 | void |
| 981 | finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| 982 | Output_section** dot_section) |
| 983 | { |
| 984 | *dot_value = this->final_dot_value_; |
| 985 | *dot_section = this->final_dot_section_; |
| 986 | } |
| 987 | |
| 988 | // See whether we match FILE_NAME and SECTION_NAME as an input |
| 989 | // section. |
| 990 | bool |
| 991 | match_name(const char* file_name, const char* section_name) const; |
| 992 | |
| 993 | // Set the section address. |
| 994 | void |
| 995 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 996 | uint64_t subalign, uint64_t* dot_value, |
| 997 | Output_section**, std::string* fill, |
| 998 | Input_section_list*); |
| 999 | |
| 1000 | // Print for debugging. |
| 1001 | void |
| 1002 | print(FILE* f) const; |
| 1003 | |
| 1004 | private: |
| 1005 | // An input section pattern. |
| 1006 | struct Input_section_pattern |
| 1007 | { |
| 1008 | std::string pattern; |
| 1009 | bool pattern_is_wildcard; |
| 1010 | Sort_wildcard sort; |
| 1011 | |
| 1012 | Input_section_pattern(const char* patterna, size_t patternlena, |
| 1013 | Sort_wildcard sorta) |
| 1014 | : pattern(patterna, patternlena), |
| 1015 | pattern_is_wildcard(is_wildcard_string(this->pattern)), |
| 1016 | sort(sorta) |
| 1017 | { } |
| 1018 | }; |
| 1019 | |
| 1020 | typedef std::vector<Input_section_pattern> Input_section_patterns; |
| 1021 | |
| 1022 | // Filename_exclusions is a pair of filename pattern and a bool |
| 1023 | // indicating whether the filename is a wildcard. |
| 1024 | typedef std::vector<std::pair<std::string, bool> > Filename_exclusions; |
| 1025 | |
| 1026 | // Return whether STRING matches PATTERN, where IS_WILDCARD_PATTERN |
| 1027 | // indicates whether this is a wildcard pattern. |
| 1028 | static inline bool |
| 1029 | match(const char* string, const char* pattern, bool is_wildcard_pattern) |
| 1030 | { |
| 1031 | return (is_wildcard_pattern |
| 1032 | ? fnmatch(pattern, string, 0) == 0 |
| 1033 | : strcmp(string, pattern) == 0); |
| 1034 | } |
| 1035 | |
| 1036 | // See if we match a file name. |
| 1037 | bool |
| 1038 | match_file_name(const char* file_name) const; |
| 1039 | |
| 1040 | // The file name pattern. If this is the empty string, we match all |
| 1041 | // files. |
| 1042 | std::string filename_pattern_; |
| 1043 | // Whether the file name pattern is a wildcard. |
| 1044 | bool filename_is_wildcard_; |
| 1045 | // How the file names should be sorted. This may only be |
| 1046 | // SORT_WILDCARD_NONE or SORT_WILDCARD_BY_NAME. |
| 1047 | Sort_wildcard filename_sort_; |
| 1048 | // The list of file names to exclude. |
| 1049 | Filename_exclusions filename_exclusions_; |
| 1050 | // The list of input section patterns. |
| 1051 | Input_section_patterns input_section_patterns_; |
| 1052 | // Whether to keep this section when garbage collecting. |
| 1053 | bool keep_; |
| 1054 | // The value of dot after including all matching sections. |
| 1055 | uint64_t final_dot_value_; |
| 1056 | // The section where dot is defined after including all matching |
| 1057 | // sections. |
| 1058 | Output_section* final_dot_section_; |
| 1059 | }; |
| 1060 | |
| 1061 | // Construct Output_section_element_input. The parser records strings |
| 1062 | // as pointers into a copy of the script file, which will go away when |
| 1063 | // parsing is complete. We make sure they are in std::string objects. |
| 1064 | |
| 1065 | Output_section_element_input::Output_section_element_input( |
| 1066 | const Input_section_spec* spec, |
| 1067 | bool keep) |
| 1068 | : filename_pattern_(), |
| 1069 | filename_is_wildcard_(false), |
| 1070 | filename_sort_(spec->file.sort), |
| 1071 | filename_exclusions_(), |
| 1072 | input_section_patterns_(), |
| 1073 | keep_(keep), |
| 1074 | final_dot_value_(0), |
| 1075 | final_dot_section_(NULL) |
| 1076 | { |
| 1077 | // The filename pattern "*" is common, and matches all files. Turn |
| 1078 | // it into the empty string. |
| 1079 | if (spec->file.name.length != 1 || spec->file.name.value[0] != '*') |
| 1080 | this->filename_pattern_.assign(spec->file.name.value, |
| 1081 | spec->file.name.length); |
| 1082 | this->filename_is_wildcard_ = is_wildcard_string(this->filename_pattern_); |
| 1083 | |
| 1084 | if (spec->input_sections.exclude != NULL) |
| 1085 | { |
| 1086 | for (String_list::const_iterator p = |
| 1087 | spec->input_sections.exclude->begin(); |
| 1088 | p != spec->input_sections.exclude->end(); |
| 1089 | ++p) |
| 1090 | { |
| 1091 | bool is_wildcard = is_wildcard_string(*p); |
| 1092 | this->filename_exclusions_.push_back(std::make_pair(*p, |
| 1093 | is_wildcard)); |
| 1094 | } |
| 1095 | } |
| 1096 | |
| 1097 | if (spec->input_sections.sections != NULL) |
| 1098 | { |
| 1099 | Input_section_patterns& isp(this->input_section_patterns_); |
| 1100 | for (String_sort_list::const_iterator p = |
| 1101 | spec->input_sections.sections->begin(); |
| 1102 | p != spec->input_sections.sections->end(); |
| 1103 | ++p) |
| 1104 | isp.push_back(Input_section_pattern(p->name.value, p->name.length, |
| 1105 | p->sort)); |
| 1106 | } |
| 1107 | } |
| 1108 | |
| 1109 | // See whether we match FILE_NAME. |
| 1110 | |
| 1111 | bool |
| 1112 | Output_section_element_input::match_file_name(const char* file_name) const |
| 1113 | { |
| 1114 | if (!this->filename_pattern_.empty()) |
| 1115 | { |
| 1116 | // If we were called with no filename, we refuse to match a |
| 1117 | // pattern which requires a file name. |
| 1118 | if (file_name == NULL) |
| 1119 | return false; |
| 1120 | |
| 1121 | if (!match(file_name, this->filename_pattern_.c_str(), |
| 1122 | this->filename_is_wildcard_)) |
| 1123 | return false; |
| 1124 | } |
| 1125 | |
| 1126 | if (file_name != NULL) |
| 1127 | { |
| 1128 | // Now we have to see whether FILE_NAME matches one of the |
| 1129 | // exclusion patterns, if any. |
| 1130 | for (Filename_exclusions::const_iterator p = |
| 1131 | this->filename_exclusions_.begin(); |
| 1132 | p != this->filename_exclusions_.end(); |
| 1133 | ++p) |
| 1134 | { |
| 1135 | if (match(file_name, p->first.c_str(), p->second)) |
| 1136 | return false; |
| 1137 | } |
| 1138 | } |
| 1139 | |
| 1140 | return true; |
| 1141 | } |
| 1142 | |
| 1143 | // See whether we match FILE_NAME and SECTION_NAME. |
| 1144 | |
| 1145 | bool |
| 1146 | Output_section_element_input::match_name(const char* file_name, |
| 1147 | const char* section_name) const |
| 1148 | { |
| 1149 | if (!this->match_file_name(file_name)) |
| 1150 | return false; |
| 1151 | |
| 1152 | // If there are no section name patterns, then we match. |
| 1153 | if (this->input_section_patterns_.empty()) |
| 1154 | return true; |
| 1155 | |
| 1156 | // See whether we match the section name patterns. |
| 1157 | for (Input_section_patterns::const_iterator p = |
| 1158 | this->input_section_patterns_.begin(); |
| 1159 | p != this->input_section_patterns_.end(); |
| 1160 | ++p) |
| 1161 | { |
| 1162 | if (match(section_name, p->pattern.c_str(), p->pattern_is_wildcard)) |
| 1163 | return true; |
| 1164 | } |
| 1165 | |
| 1166 | // We didn't match any section names, so we didn't match. |
| 1167 | return false; |
| 1168 | } |
| 1169 | |
| 1170 | // Information we use to sort the input sections. |
| 1171 | |
| 1172 | struct Input_section_info |
| 1173 | { |
| 1174 | Relobj* relobj; |
| 1175 | unsigned int shndx; |
| 1176 | std::string section_name; |
| 1177 | uint64_t size; |
| 1178 | uint64_t addralign; |
| 1179 | }; |
| 1180 | |
| 1181 | // A class to sort the input sections. |
| 1182 | |
| 1183 | class Input_section_sorter |
| 1184 | { |
| 1185 | public: |
| 1186 | Input_section_sorter(Sort_wildcard filename_sort, Sort_wildcard section_sort) |
| 1187 | : filename_sort_(filename_sort), section_sort_(section_sort) |
| 1188 | { } |
| 1189 | |
| 1190 | bool |
| 1191 | operator()(const Input_section_info&, const Input_section_info&) const; |
| 1192 | |
| 1193 | private: |
| 1194 | Sort_wildcard filename_sort_; |
| 1195 | Sort_wildcard section_sort_; |
| 1196 | }; |
| 1197 | |
| 1198 | bool |
| 1199 | Input_section_sorter::operator()(const Input_section_info& isi1, |
| 1200 | const Input_section_info& isi2) const |
| 1201 | { |
| 1202 | if (this->section_sort_ == SORT_WILDCARD_BY_NAME |
| 1203 | || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT |
| 1204 | || (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME |
| 1205 | && isi1.addralign == isi2.addralign)) |
| 1206 | { |
| 1207 | if (isi1.section_name != isi2.section_name) |
| 1208 | return isi1.section_name < isi2.section_name; |
| 1209 | } |
| 1210 | if (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT |
| 1211 | || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT |
| 1212 | || this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME) |
| 1213 | { |
| 1214 | if (isi1.addralign != isi2.addralign) |
| 1215 | return isi1.addralign < isi2.addralign; |
| 1216 | } |
| 1217 | if (this->filename_sort_ == SORT_WILDCARD_BY_NAME) |
| 1218 | { |
| 1219 | if (isi1.relobj->name() != isi2.relobj->name()) |
| 1220 | return isi1.relobj->name() < isi2.relobj->name(); |
| 1221 | } |
| 1222 | |
| 1223 | // Otherwise we leave them in the same order. |
| 1224 | return false; |
| 1225 | } |
| 1226 | |
| 1227 | // Set the section address. Look in INPUT_SECTIONS for sections which |
| 1228 | // match this spec, sort them as specified, and add them to the output |
| 1229 | // section. |
| 1230 | |
| 1231 | void |
| 1232 | Output_section_element_input::set_section_addresses( |
| 1233 | Symbol_table*, |
| 1234 | Layout*, |
| 1235 | Output_section* output_section, |
| 1236 | uint64_t subalign, |
| 1237 | uint64_t* dot_value, |
| 1238 | Output_section** dot_section, |
| 1239 | std::string* fill, |
| 1240 | Input_section_list* input_sections) |
| 1241 | { |
| 1242 | // We build a list of sections which match each |
| 1243 | // Input_section_pattern. |
| 1244 | |
| 1245 | typedef std::vector<std::vector<Input_section_info> > Matching_sections; |
| 1246 | size_t input_pattern_count = this->input_section_patterns_.size(); |
| 1247 | if (input_pattern_count == 0) |
| 1248 | input_pattern_count = 1; |
| 1249 | Matching_sections matching_sections(input_pattern_count); |
| 1250 | |
| 1251 | // Look through the list of sections for this output section. Add |
| 1252 | // each one which matches to one of the elements of |
| 1253 | // MATCHING_SECTIONS. |
| 1254 | |
| 1255 | Input_section_list::iterator p = input_sections->begin(); |
| 1256 | while (p != input_sections->end()) |
| 1257 | { |
| 1258 | // Calling section_name and section_addralign is not very |
| 1259 | // efficient. |
| 1260 | Input_section_info isi; |
| 1261 | isi.relobj = p->first; |
| 1262 | isi.shndx = p->second; |
| 1263 | |
| 1264 | // Lock the object so that we can get information about the |
| 1265 | // section. This is OK since we know we are single-threaded |
| 1266 | // here. |
| 1267 | { |
| 1268 | const Task* task = reinterpret_cast<const Task*>(-1); |
| 1269 | Task_lock_obj<Object> tl(task, p->first); |
| 1270 | |
| 1271 | isi.section_name = p->first->section_name(p->second); |
| 1272 | isi.size = p->first->section_size(p->second); |
| 1273 | isi.addralign = p->first->section_addralign(p->second); |
| 1274 | } |
| 1275 | |
| 1276 | if (!this->match_file_name(isi.relobj->name().c_str())) |
| 1277 | ++p; |
| 1278 | else if (this->input_section_patterns_.empty()) |
| 1279 | { |
| 1280 | matching_sections[0].push_back(isi); |
| 1281 | p = input_sections->erase(p); |
| 1282 | } |
| 1283 | else |
| 1284 | { |
| 1285 | size_t i; |
| 1286 | for (i = 0; i < input_pattern_count; ++i) |
| 1287 | { |
| 1288 | const Input_section_pattern& |
| 1289 | isp(this->input_section_patterns_[i]); |
| 1290 | if (match(isi.section_name.c_str(), isp.pattern.c_str(), |
| 1291 | isp.pattern_is_wildcard)) |
| 1292 | break; |
| 1293 | } |
| 1294 | |
| 1295 | if (i >= this->input_section_patterns_.size()) |
| 1296 | ++p; |
| 1297 | else |
| 1298 | { |
| 1299 | matching_sections[i].push_back(isi); |
| 1300 | p = input_sections->erase(p); |
| 1301 | } |
| 1302 | } |
| 1303 | } |
| 1304 | |
| 1305 | // Look through MATCHING_SECTIONS. Sort each one as specified, |
| 1306 | // using a stable sort so that we get the default order when |
| 1307 | // sections are otherwise equal. Add each input section to the |
| 1308 | // output section. |
| 1309 | |
| 1310 | for (size_t i = 0; i < input_pattern_count; ++i) |
| 1311 | { |
| 1312 | if (matching_sections[i].empty()) |
| 1313 | continue; |
| 1314 | |
| 1315 | gold_assert(output_section != NULL); |
| 1316 | |
| 1317 | const Input_section_pattern& isp(this->input_section_patterns_[i]); |
| 1318 | if (isp.sort != SORT_WILDCARD_NONE |
| 1319 | || this->filename_sort_ != SORT_WILDCARD_NONE) |
| 1320 | std::stable_sort(matching_sections[i].begin(), |
| 1321 | matching_sections[i].end(), |
| 1322 | Input_section_sorter(this->filename_sort_, |
| 1323 | isp.sort)); |
| 1324 | |
| 1325 | for (std::vector<Input_section_info>::const_iterator p = |
| 1326 | matching_sections[i].begin(); |
| 1327 | p != matching_sections[i].end(); |
| 1328 | ++p) |
| 1329 | { |
| 1330 | uint64_t this_subalign = p->addralign; |
| 1331 | if (this_subalign < subalign) |
| 1332 | this_subalign = subalign; |
| 1333 | |
| 1334 | uint64_t address = align_address(*dot_value, this_subalign); |
| 1335 | |
| 1336 | if (address > *dot_value && !fill->empty()) |
| 1337 | { |
| 1338 | section_size_type length = |
| 1339 | convert_to_section_size_type(address - *dot_value); |
| 1340 | std::string this_fill = this->get_fill_string(fill, length); |
| 1341 | Output_section_data* posd = new Output_data_const(this_fill, 0); |
| 1342 | output_section->add_output_section_data(posd); |
| 1343 | } |
| 1344 | |
| 1345 | output_section->add_input_section_for_script(p->relobj, |
| 1346 | p->shndx, |
| 1347 | p->size, |
| 1348 | this_subalign); |
| 1349 | |
| 1350 | *dot_value = address + p->size; |
| 1351 | } |
| 1352 | } |
| 1353 | |
| 1354 | this->final_dot_value_ = *dot_value; |
| 1355 | this->final_dot_section_ = *dot_section; |
| 1356 | } |
| 1357 | |
| 1358 | // Print for debugging. |
| 1359 | |
| 1360 | void |
| 1361 | Output_section_element_input::print(FILE* f) const |
| 1362 | { |
| 1363 | fprintf(f, " "); |
| 1364 | |
| 1365 | if (this->keep_) |
| 1366 | fprintf(f, "KEEP("); |
| 1367 | |
| 1368 | if (!this->filename_pattern_.empty()) |
| 1369 | { |
| 1370 | bool need_close_paren = false; |
| 1371 | switch (this->filename_sort_) |
| 1372 | { |
| 1373 | case SORT_WILDCARD_NONE: |
| 1374 | break; |
| 1375 | case SORT_WILDCARD_BY_NAME: |
| 1376 | fprintf(f, "SORT_BY_NAME("); |
| 1377 | need_close_paren = true; |
| 1378 | break; |
| 1379 | default: |
| 1380 | gold_unreachable(); |
| 1381 | } |
| 1382 | |
| 1383 | fprintf(f, "%s", this->filename_pattern_.c_str()); |
| 1384 | |
| 1385 | if (need_close_paren) |
| 1386 | fprintf(f, ")"); |
| 1387 | } |
| 1388 | |
| 1389 | if (!this->input_section_patterns_.empty() |
| 1390 | || !this->filename_exclusions_.empty()) |
| 1391 | { |
| 1392 | fprintf(f, "("); |
| 1393 | |
| 1394 | bool need_space = false; |
| 1395 | if (!this->filename_exclusions_.empty()) |
| 1396 | { |
| 1397 | fprintf(f, "EXCLUDE_FILE("); |
| 1398 | bool need_comma = false; |
| 1399 | for (Filename_exclusions::const_iterator p = |
| 1400 | this->filename_exclusions_.begin(); |
| 1401 | p != this->filename_exclusions_.end(); |
| 1402 | ++p) |
| 1403 | { |
| 1404 | if (need_comma) |
| 1405 | fprintf(f, ", "); |
| 1406 | fprintf(f, "%s", p->first.c_str()); |
| 1407 | need_comma = true; |
| 1408 | } |
| 1409 | fprintf(f, ")"); |
| 1410 | need_space = true; |
| 1411 | } |
| 1412 | |
| 1413 | for (Input_section_patterns::const_iterator p = |
| 1414 | this->input_section_patterns_.begin(); |
| 1415 | p != this->input_section_patterns_.end(); |
| 1416 | ++p) |
| 1417 | { |
| 1418 | if (need_space) |
| 1419 | fprintf(f, " "); |
| 1420 | |
| 1421 | int close_parens = 0; |
| 1422 | switch (p->sort) |
| 1423 | { |
| 1424 | case SORT_WILDCARD_NONE: |
| 1425 | break; |
| 1426 | case SORT_WILDCARD_BY_NAME: |
| 1427 | fprintf(f, "SORT_BY_NAME("); |
| 1428 | close_parens = 1; |
| 1429 | break; |
| 1430 | case SORT_WILDCARD_BY_ALIGNMENT: |
| 1431 | fprintf(f, "SORT_BY_ALIGNMENT("); |
| 1432 | close_parens = 1; |
| 1433 | break; |
| 1434 | case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT: |
| 1435 | fprintf(f, "SORT_BY_NAME(SORT_BY_ALIGNMENT("); |
| 1436 | close_parens = 2; |
| 1437 | break; |
| 1438 | case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME: |
| 1439 | fprintf(f, "SORT_BY_ALIGNMENT(SORT_BY_NAME("); |
| 1440 | close_parens = 2; |
| 1441 | break; |
| 1442 | default: |
| 1443 | gold_unreachable(); |
| 1444 | } |
| 1445 | |
| 1446 | fprintf(f, "%s", p->pattern.c_str()); |
| 1447 | |
| 1448 | for (int i = 0; i < close_parens; ++i) |
| 1449 | fprintf(f, ")"); |
| 1450 | |
| 1451 | need_space = true; |
| 1452 | } |
| 1453 | |
| 1454 | fprintf(f, ")"); |
| 1455 | } |
| 1456 | |
| 1457 | if (this->keep_) |
| 1458 | fprintf(f, ")"); |
| 1459 | |
| 1460 | fprintf(f, "\n"); |
| 1461 | } |
| 1462 | |
| 1463 | // An output section. |
| 1464 | |
| 1465 | class Output_section_definition : public Sections_element |
| 1466 | { |
| 1467 | public: |
| 1468 | typedef Output_section_element::Input_section_list Input_section_list; |
| 1469 | |
| 1470 | Output_section_definition(const char* name, size_t namelen, |
| 1471 | const Parser_output_section_header* header); |
| 1472 | |
| 1473 | // Finish the output section with the information in the trailer. |
| 1474 | void |
| 1475 | finish(const Parser_output_section_trailer* trailer); |
| 1476 | |
| 1477 | // Add a symbol to be defined. |
| 1478 | void |
| 1479 | add_symbol_assignment(const char* name, size_t length, Expression* value, |
| 1480 | bool provide, bool hidden); |
| 1481 | |
| 1482 | // Add an assignment to the special dot symbol. |
| 1483 | void |
| 1484 | add_dot_assignment(Expression* value); |
| 1485 | |
| 1486 | // Add an assertion. |
| 1487 | void |
| 1488 | add_assertion(Expression* check, const char* message, size_t messagelen); |
| 1489 | |
| 1490 | // Add a data item to the current output section. |
| 1491 | void |
| 1492 | add_data(int size, bool is_signed, Expression* val); |
| 1493 | |
| 1494 | // Add a setting for the fill value. |
| 1495 | void |
| 1496 | add_fill(Expression* val); |
| 1497 | |
| 1498 | // Add an input section specification. |
| 1499 | void |
| 1500 | add_input_section(const Input_section_spec* spec, bool keep); |
| 1501 | |
| 1502 | // Return whether the output section is relro. |
| 1503 | bool |
| 1504 | is_relro() const |
| 1505 | { return this->is_relro_; } |
| 1506 | |
| 1507 | // Record that the output section is relro. |
| 1508 | void |
| 1509 | set_is_relro() |
| 1510 | { this->is_relro_ = true; } |
| 1511 | |
| 1512 | // Create any required output sections. |
| 1513 | void |
| 1514 | create_sections(Layout*); |
| 1515 | |
| 1516 | // Add any symbols being defined to the symbol table. |
| 1517 | void |
| 1518 | add_symbols_to_table(Symbol_table* symtab); |
| 1519 | |
| 1520 | // Finalize symbols and check assertions. |
| 1521 | void |
| 1522 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*); |
| 1523 | |
| 1524 | // Return the output section name to use for an input file name and |
| 1525 | // section name. |
| 1526 | const char* |
| 1527 | output_section_name(const char* file_name, const char* section_name, |
| 1528 | Output_section***); |
| 1529 | |
| 1530 | // Initialize OSP with an output section. |
| 1531 | void |
| 1532 | orphan_section_init(Orphan_section_placement* osp, |
| 1533 | Script_sections::Elements_iterator p) |
| 1534 | { osp->output_section_init(this->name_, this->output_section_, p); } |
| 1535 | |
| 1536 | // Set the section address. |
| 1537 | void |
| 1538 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 1539 | uint64_t* dot_value, uint64_t* load_address); |
| 1540 | |
| 1541 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 1542 | // this section is constrained, and the input sections do not match, |
| 1543 | // return the constraint, and set *POSD. |
| 1544 | Section_constraint |
| 1545 | check_constraint(Output_section_definition** posd); |
| 1546 | |
| 1547 | // See if this is the alternate output section for a constrained |
| 1548 | // output section. If it is, transfer the Output_section and return |
| 1549 | // true. Otherwise return false. |
| 1550 | bool |
| 1551 | alternate_constraint(Output_section_definition*, Section_constraint); |
| 1552 | |
| 1553 | // Get the list of segments to use for an allocated section when |
| 1554 | // using a PHDRS clause. |
| 1555 | Output_section* |
| 1556 | allocate_to_segment(String_list** phdrs_list, bool* orphan); |
| 1557 | |
| 1558 | // Look for an output section by name and return the address, the |
| 1559 | // load address, the alignment, and the size. This is used when an |
| 1560 | // expression refers to an output section which was not actually |
| 1561 | // created. This returns true if the section was found, false |
| 1562 | // otherwise. |
| 1563 | bool |
| 1564 | get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| 1565 | uint64_t*) const; |
| 1566 | |
| 1567 | // Return the associated Output_section if there is one. |
| 1568 | Output_section* |
| 1569 | get_output_section() const |
| 1570 | { return this->output_section_; } |
| 1571 | |
| 1572 | // Print the contents to the FILE. This is for debugging. |
| 1573 | void |
| 1574 | print(FILE*) const; |
| 1575 | |
| 1576 | private: |
| 1577 | typedef std::vector<Output_section_element*> Output_section_elements; |
| 1578 | |
| 1579 | // The output section name. |
| 1580 | std::string name_; |
| 1581 | // The address. This may be NULL. |
| 1582 | Expression* address_; |
| 1583 | // The load address. This may be NULL. |
| 1584 | Expression* load_address_; |
| 1585 | // The alignment. This may be NULL. |
| 1586 | Expression* align_; |
| 1587 | // The input section alignment. This may be NULL. |
| 1588 | Expression* subalign_; |
| 1589 | // The constraint, if any. |
| 1590 | Section_constraint constraint_; |
| 1591 | // The fill value. This may be NULL. |
| 1592 | Expression* fill_; |
| 1593 | // The list of segments this section should go into. This may be |
| 1594 | // NULL. |
| 1595 | String_list* phdrs_; |
| 1596 | // The list of elements defining the section. |
| 1597 | Output_section_elements elements_; |
| 1598 | // The Output_section created for this definition. This will be |
| 1599 | // NULL if none was created. |
| 1600 | Output_section* output_section_; |
| 1601 | // The address after it has been evaluated. |
| 1602 | uint64_t evaluated_address_; |
| 1603 | // The load address after it has been evaluated. |
| 1604 | uint64_t evaluated_load_address_; |
| 1605 | // The alignment after it has been evaluated. |
| 1606 | uint64_t evaluated_addralign_; |
| 1607 | // The output section is relro. |
| 1608 | bool is_relro_; |
| 1609 | }; |
| 1610 | |
| 1611 | // Constructor. |
| 1612 | |
| 1613 | Output_section_definition::Output_section_definition( |
| 1614 | const char* name, |
| 1615 | size_t namelen, |
| 1616 | const Parser_output_section_header* header) |
| 1617 | : name_(name, namelen), |
| 1618 | address_(header->address), |
| 1619 | load_address_(header->load_address), |
| 1620 | align_(header->align), |
| 1621 | subalign_(header->subalign), |
| 1622 | constraint_(header->constraint), |
| 1623 | fill_(NULL), |
| 1624 | phdrs_(NULL), |
| 1625 | elements_(), |
| 1626 | output_section_(NULL), |
| 1627 | evaluated_address_(0), |
| 1628 | evaluated_load_address_(0), |
| 1629 | evaluated_addralign_(0), |
| 1630 | is_relro_(false) |
| 1631 | { |
| 1632 | } |
| 1633 | |
| 1634 | // Finish an output section. |
| 1635 | |
| 1636 | void |
| 1637 | Output_section_definition::finish(const Parser_output_section_trailer* trailer) |
| 1638 | { |
| 1639 | this->fill_ = trailer->fill; |
| 1640 | this->phdrs_ = trailer->phdrs; |
| 1641 | } |
| 1642 | |
| 1643 | // Add a symbol to be defined. |
| 1644 | |
| 1645 | void |
| 1646 | Output_section_definition::add_symbol_assignment(const char* name, |
| 1647 | size_t length, |
| 1648 | Expression* value, |
| 1649 | bool provide, |
| 1650 | bool hidden) |
| 1651 | { |
| 1652 | Output_section_element* p = new Output_section_element_assignment(name, |
| 1653 | length, |
| 1654 | value, |
| 1655 | provide, |
| 1656 | hidden); |
| 1657 | this->elements_.push_back(p); |
| 1658 | } |
| 1659 | |
| 1660 | // Add an assignment to the special dot symbol. |
| 1661 | |
| 1662 | void |
| 1663 | Output_section_definition::add_dot_assignment(Expression* value) |
| 1664 | { |
| 1665 | Output_section_element* p = new Output_section_element_dot_assignment(value); |
| 1666 | this->elements_.push_back(p); |
| 1667 | } |
| 1668 | |
| 1669 | // Add an assertion. |
| 1670 | |
| 1671 | void |
| 1672 | Output_section_definition::add_assertion(Expression* check, |
| 1673 | const char* message, |
| 1674 | size_t messagelen) |
| 1675 | { |
| 1676 | Output_section_element* p = new Output_section_element_assertion(check, |
| 1677 | message, |
| 1678 | messagelen); |
| 1679 | this->elements_.push_back(p); |
| 1680 | } |
| 1681 | |
| 1682 | // Add a data item to the current output section. |
| 1683 | |
| 1684 | void |
| 1685 | Output_section_definition::add_data(int size, bool is_signed, Expression* val) |
| 1686 | { |
| 1687 | Output_section_element* p = new Output_section_element_data(size, is_signed, |
| 1688 | val); |
| 1689 | this->elements_.push_back(p); |
| 1690 | } |
| 1691 | |
| 1692 | // Add a setting for the fill value. |
| 1693 | |
| 1694 | void |
| 1695 | Output_section_definition::add_fill(Expression* val) |
| 1696 | { |
| 1697 | Output_section_element* p = new Output_section_element_fill(val); |
| 1698 | this->elements_.push_back(p); |
| 1699 | } |
| 1700 | |
| 1701 | // Add an input section specification. |
| 1702 | |
| 1703 | void |
| 1704 | Output_section_definition::add_input_section(const Input_section_spec* spec, |
| 1705 | bool keep) |
| 1706 | { |
| 1707 | Output_section_element* p = new Output_section_element_input(spec, keep); |
| 1708 | this->elements_.push_back(p); |
| 1709 | } |
| 1710 | |
| 1711 | // Create any required output sections. We need an output section if |
| 1712 | // there is a data statement here. |
| 1713 | |
| 1714 | void |
| 1715 | Output_section_definition::create_sections(Layout* layout) |
| 1716 | { |
| 1717 | if (this->output_section_ != NULL) |
| 1718 | return; |
| 1719 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 1720 | p != this->elements_.end(); |
| 1721 | ++p) |
| 1722 | { |
| 1723 | if ((*p)->needs_output_section()) |
| 1724 | { |
| 1725 | const char* name = this->name_.c_str(); |
| 1726 | this->output_section_ = layout->make_output_section_for_script(name); |
| 1727 | return; |
| 1728 | } |
| 1729 | } |
| 1730 | } |
| 1731 | |
| 1732 | // Add any symbols being defined to the symbol table. |
| 1733 | |
| 1734 | void |
| 1735 | Output_section_definition::add_symbols_to_table(Symbol_table* symtab) |
| 1736 | { |
| 1737 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 1738 | p != this->elements_.end(); |
| 1739 | ++p) |
| 1740 | (*p)->add_symbols_to_table(symtab); |
| 1741 | } |
| 1742 | |
| 1743 | // Finalize symbols and check assertions. |
| 1744 | |
| 1745 | void |
| 1746 | Output_section_definition::finalize_symbols(Symbol_table* symtab, |
| 1747 | const Layout* layout, |
| 1748 | uint64_t* dot_value) |
| 1749 | { |
| 1750 | if (this->output_section_ != NULL) |
| 1751 | *dot_value = this->output_section_->address(); |
| 1752 | else |
| 1753 | { |
| 1754 | uint64_t address = *dot_value; |
| 1755 | if (this->address_ != NULL) |
| 1756 | { |
| 1757 | Output_section* dummy; |
| 1758 | address = this->address_->eval_with_dot(symtab, layout, true, |
| 1759 | *dot_value, NULL, |
| 1760 | &dummy); |
| 1761 | } |
| 1762 | if (this->align_ != NULL) |
| 1763 | { |
| 1764 | Output_section* dummy; |
| 1765 | uint64_t align = this->align_->eval_with_dot(symtab, layout, true, |
| 1766 | *dot_value, |
| 1767 | NULL, |
| 1768 | &dummy); |
| 1769 | address = align_address(address, align); |
| 1770 | } |
| 1771 | *dot_value = address; |
| 1772 | } |
| 1773 | |
| 1774 | Output_section* dot_section = this->output_section_; |
| 1775 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 1776 | p != this->elements_.end(); |
| 1777 | ++p) |
| 1778 | (*p)->finalize_symbols(symtab, layout, dot_value, &dot_section); |
| 1779 | } |
| 1780 | |
| 1781 | // Return the output section name to use for an input section name. |
| 1782 | |
| 1783 | const char* |
| 1784 | Output_section_definition::output_section_name(const char* file_name, |
| 1785 | const char* section_name, |
| 1786 | Output_section*** slot) |
| 1787 | { |
| 1788 | // Ask each element whether it matches NAME. |
| 1789 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 1790 | p != this->elements_.end(); |
| 1791 | ++p) |
| 1792 | { |
| 1793 | if ((*p)->match_name(file_name, section_name)) |
| 1794 | { |
| 1795 | // We found a match for NAME, which means that it should go |
| 1796 | // into this output section. |
| 1797 | *slot = &this->output_section_; |
| 1798 | return this->name_.c_str(); |
| 1799 | } |
| 1800 | } |
| 1801 | |
| 1802 | // We don't know about this section name. |
| 1803 | return NULL; |
| 1804 | } |
| 1805 | |
| 1806 | // Set the section address. Note that the OUTPUT_SECTION_ field will |
| 1807 | // be NULL if no input sections were mapped to this output section. |
| 1808 | // We still have to adjust dot and process symbol assignments. |
| 1809 | |
| 1810 | void |
| 1811 | Output_section_definition::set_section_addresses(Symbol_table* symtab, |
| 1812 | Layout* layout, |
| 1813 | uint64_t* dot_value, |
| 1814 | uint64_t* load_address) |
| 1815 | { |
| 1816 | uint64_t address; |
| 1817 | if (this->address_ == NULL) |
| 1818 | address = *dot_value; |
| 1819 | else |
| 1820 | { |
| 1821 | Output_section* dummy; |
| 1822 | address = this->address_->eval_with_dot(symtab, layout, true, |
| 1823 | *dot_value, NULL, &dummy); |
| 1824 | } |
| 1825 | |
| 1826 | uint64_t align; |
| 1827 | if (this->align_ == NULL) |
| 1828 | { |
| 1829 | if (this->output_section_ == NULL) |
| 1830 | align = 0; |
| 1831 | else |
| 1832 | align = this->output_section_->addralign(); |
| 1833 | } |
| 1834 | else |
| 1835 | { |
| 1836 | Output_section* align_section; |
| 1837 | align = this->align_->eval_with_dot(symtab, layout, true, *dot_value, |
| 1838 | NULL, &align_section); |
| 1839 | if (align_section != NULL) |
| 1840 | gold_warning(_("alignment of section %s is not absolute"), |
| 1841 | this->name_.c_str()); |
| 1842 | if (this->output_section_ != NULL) |
| 1843 | this->output_section_->set_addralign(align); |
| 1844 | } |
| 1845 | |
| 1846 | address = align_address(address, align); |
| 1847 | |
| 1848 | uint64_t start_address = address; |
| 1849 | |
| 1850 | *dot_value = address; |
| 1851 | |
| 1852 | // The address of non-SHF_ALLOC sections is forced to zero, |
| 1853 | // regardless of what the linker script wants. |
| 1854 | if (this->output_section_ != NULL |
| 1855 | && (this->output_section_->flags() & elfcpp::SHF_ALLOC) != 0) |
| 1856 | this->output_section_->set_address(address); |
| 1857 | |
| 1858 | this->evaluated_address_ = address; |
| 1859 | this->evaluated_addralign_ = align; |
| 1860 | |
| 1861 | if (this->load_address_ == NULL) |
| 1862 | this->evaluated_load_address_ = address; |
| 1863 | else |
| 1864 | { |
| 1865 | Output_section* dummy; |
| 1866 | uint64_t load_address = |
| 1867 | this->load_address_->eval_with_dot(symtab, layout, true, *dot_value, |
| 1868 | this->output_section_, &dummy); |
| 1869 | if (this->output_section_ != NULL) |
| 1870 | this->output_section_->set_load_address(load_address); |
| 1871 | this->evaluated_load_address_ = load_address; |
| 1872 | } |
| 1873 | |
| 1874 | uint64_t subalign; |
| 1875 | if (this->subalign_ == NULL) |
| 1876 | subalign = 0; |
| 1877 | else |
| 1878 | { |
| 1879 | Output_section* subalign_section; |
| 1880 | subalign = this->subalign_->eval_with_dot(symtab, layout, true, |
| 1881 | *dot_value, NULL, |
| 1882 | &subalign_section); |
| 1883 | if (subalign_section != NULL) |
| 1884 | gold_warning(_("subalign of section %s is not absolute"), |
| 1885 | this->name_.c_str()); |
| 1886 | } |
| 1887 | |
| 1888 | std::string fill; |
| 1889 | if (this->fill_ != NULL) |
| 1890 | { |
| 1891 | // FIXME: The GNU linker supports fill values of arbitrary |
| 1892 | // length. |
| 1893 | Output_section* fill_section; |
| 1894 | uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout, true, |
| 1895 | *dot_value, |
| 1896 | NULL, |
| 1897 | &fill_section); |
| 1898 | if (fill_section != NULL) |
| 1899 | gold_warning(_("fill of section %s is not absolute"), |
| 1900 | this->name_.c_str()); |
| 1901 | unsigned char fill_buff[4]; |
| 1902 | elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| 1903 | fill.assign(reinterpret_cast<char*>(fill_buff), 4); |
| 1904 | } |
| 1905 | |
| 1906 | Input_section_list input_sections; |
| 1907 | if (this->output_section_ != NULL) |
| 1908 | { |
| 1909 | // Get the list of input sections attached to this output |
| 1910 | // section. This will leave the output section with only |
| 1911 | // Output_section_data entries. |
| 1912 | address += this->output_section_->get_input_sections(address, |
| 1913 | fill, |
| 1914 | &input_sections); |
| 1915 | *dot_value = address; |
| 1916 | } |
| 1917 | |
| 1918 | Output_section* dot_section = this->output_section_; |
| 1919 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 1920 | p != this->elements_.end(); |
| 1921 | ++p) |
| 1922 | (*p)->set_section_addresses(symtab, layout, this->output_section_, |
| 1923 | subalign, dot_value, &dot_section, &fill, |
| 1924 | &input_sections); |
| 1925 | |
| 1926 | gold_assert(input_sections.empty()); |
| 1927 | |
| 1928 | if (this->load_address_ == NULL || this->output_section_ == NULL) |
| 1929 | *load_address = *dot_value; |
| 1930 | else |
| 1931 | *load_address = (this->output_section_->load_address() |
| 1932 | + (*dot_value - start_address)); |
| 1933 | |
| 1934 | if (this->output_section_ != NULL) |
| 1935 | { |
| 1936 | if (this->is_relro_) |
| 1937 | this->output_section_->set_is_relro(); |
| 1938 | else |
| 1939 | this->output_section_->clear_is_relro(); |
| 1940 | } |
| 1941 | } |
| 1942 | |
| 1943 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 1944 | // this section is constrained, and the input sections do not match, |
| 1945 | // return the constraint, and set *POSD. |
| 1946 | |
| 1947 | Section_constraint |
| 1948 | Output_section_definition::check_constraint(Output_section_definition** posd) |
| 1949 | { |
| 1950 | switch (this->constraint_) |
| 1951 | { |
| 1952 | case CONSTRAINT_NONE: |
| 1953 | return CONSTRAINT_NONE; |
| 1954 | |
| 1955 | case CONSTRAINT_ONLY_IF_RO: |
| 1956 | if (this->output_section_ != NULL |
| 1957 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0) |
| 1958 | { |
| 1959 | *posd = this; |
| 1960 | return CONSTRAINT_ONLY_IF_RO; |
| 1961 | } |
| 1962 | return CONSTRAINT_NONE; |
| 1963 | |
| 1964 | case CONSTRAINT_ONLY_IF_RW: |
| 1965 | if (this->output_section_ != NULL |
| 1966 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| 1967 | { |
| 1968 | *posd = this; |
| 1969 | return CONSTRAINT_ONLY_IF_RW; |
| 1970 | } |
| 1971 | return CONSTRAINT_NONE; |
| 1972 | |
| 1973 | case CONSTRAINT_SPECIAL: |
| 1974 | if (this->output_section_ != NULL) |
| 1975 | gold_error(_("SPECIAL constraints are not implemented")); |
| 1976 | return CONSTRAINT_NONE; |
| 1977 | |
| 1978 | default: |
| 1979 | gold_unreachable(); |
| 1980 | } |
| 1981 | } |
| 1982 | |
| 1983 | // See if this is the alternate output section for a constrained |
| 1984 | // output section. If it is, transfer the Output_section and return |
| 1985 | // true. Otherwise return false. |
| 1986 | |
| 1987 | bool |
| 1988 | Output_section_definition::alternate_constraint( |
| 1989 | Output_section_definition* posd, |
| 1990 | Section_constraint constraint) |
| 1991 | { |
| 1992 | if (this->name_ != posd->name_) |
| 1993 | return false; |
| 1994 | |
| 1995 | switch (constraint) |
| 1996 | { |
| 1997 | case CONSTRAINT_ONLY_IF_RO: |
| 1998 | if (this->constraint_ != CONSTRAINT_ONLY_IF_RW) |
| 1999 | return false; |
| 2000 | break; |
| 2001 | |
| 2002 | case CONSTRAINT_ONLY_IF_RW: |
| 2003 | if (this->constraint_ != CONSTRAINT_ONLY_IF_RO) |
| 2004 | return false; |
| 2005 | break; |
| 2006 | |
| 2007 | default: |
| 2008 | gold_unreachable(); |
| 2009 | } |
| 2010 | |
| 2011 | // We have found the alternate constraint. We just need to move |
| 2012 | // over the Output_section. When constraints are used properly, |
| 2013 | // THIS should not have an output_section pointer, as all the input |
| 2014 | // sections should have matched the other definition. |
| 2015 | |
| 2016 | if (this->output_section_ != NULL) |
| 2017 | gold_error(_("mismatched definition for constrained sections")); |
| 2018 | |
| 2019 | this->output_section_ = posd->output_section_; |
| 2020 | posd->output_section_ = NULL; |
| 2021 | |
| 2022 | if (this->is_relro_) |
| 2023 | this->output_section_->set_is_relro(); |
| 2024 | else |
| 2025 | this->output_section_->clear_is_relro(); |
| 2026 | |
| 2027 | return true; |
| 2028 | } |
| 2029 | |
| 2030 | // Get the list of segments to use for an allocated section when using |
| 2031 | // a PHDRS clause. |
| 2032 | |
| 2033 | Output_section* |
| 2034 | Output_section_definition::allocate_to_segment(String_list** phdrs_list, |
| 2035 | bool* orphan) |
| 2036 | { |
| 2037 | if (this->output_section_ == NULL) |
| 2038 | return NULL; |
| 2039 | if ((this->output_section_->flags() & elfcpp::SHF_ALLOC) == 0) |
| 2040 | return NULL; |
| 2041 | *orphan = false; |
| 2042 | if (this->phdrs_ != NULL) |
| 2043 | *phdrs_list = this->phdrs_; |
| 2044 | return this->output_section_; |
| 2045 | } |
| 2046 | |
| 2047 | // Look for an output section by name and return the address, the load |
| 2048 | // address, the alignment, and the size. This is used when an |
| 2049 | // expression refers to an output section which was not actually |
| 2050 | // created. This returns true if the section was found, false |
| 2051 | // otherwise. |
| 2052 | |
| 2053 | bool |
| 2054 | Output_section_definition::get_output_section_info(const char* name, |
| 2055 | uint64_t* address, |
| 2056 | uint64_t* load_address, |
| 2057 | uint64_t* addralign, |
| 2058 | uint64_t* size) const |
| 2059 | { |
| 2060 | if (this->name_ != name) |
| 2061 | return false; |
| 2062 | |
| 2063 | if (this->output_section_ != NULL) |
| 2064 | { |
| 2065 | *address = this->output_section_->address(); |
| 2066 | if (this->output_section_->has_load_address()) |
| 2067 | *load_address = this->output_section_->load_address(); |
| 2068 | else |
| 2069 | *load_address = *address; |
| 2070 | *addralign = this->output_section_->addralign(); |
| 2071 | *size = this->output_section_->current_data_size(); |
| 2072 | } |
| 2073 | else |
| 2074 | { |
| 2075 | *address = this->evaluated_address_; |
| 2076 | *load_address = this->evaluated_load_address_; |
| 2077 | *addralign = this->evaluated_addralign_; |
| 2078 | *size = 0; |
| 2079 | } |
| 2080 | |
| 2081 | return true; |
| 2082 | } |
| 2083 | |
| 2084 | // Print for debugging. |
| 2085 | |
| 2086 | void |
| 2087 | Output_section_definition::print(FILE* f) const |
| 2088 | { |
| 2089 | fprintf(f, " %s ", this->name_.c_str()); |
| 2090 | |
| 2091 | if (this->address_ != NULL) |
| 2092 | { |
| 2093 | this->address_->print(f); |
| 2094 | fprintf(f, " "); |
| 2095 | } |
| 2096 | |
| 2097 | fprintf(f, ": "); |
| 2098 | |
| 2099 | if (this->load_address_ != NULL) |
| 2100 | { |
| 2101 | fprintf(f, "AT("); |
| 2102 | this->load_address_->print(f); |
| 2103 | fprintf(f, ") "); |
| 2104 | } |
| 2105 | |
| 2106 | if (this->align_ != NULL) |
| 2107 | { |
| 2108 | fprintf(f, "ALIGN("); |
| 2109 | this->align_->print(f); |
| 2110 | fprintf(f, ") "); |
| 2111 | } |
| 2112 | |
| 2113 | if (this->subalign_ != NULL) |
| 2114 | { |
| 2115 | fprintf(f, "SUBALIGN("); |
| 2116 | this->subalign_->print(f); |
| 2117 | fprintf(f, ") "); |
| 2118 | } |
| 2119 | |
| 2120 | fprintf(f, "{\n"); |
| 2121 | |
| 2122 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 2123 | p != this->elements_.end(); |
| 2124 | ++p) |
| 2125 | (*p)->print(f); |
| 2126 | |
| 2127 | fprintf(f, " }"); |
| 2128 | |
| 2129 | if (this->fill_ != NULL) |
| 2130 | { |
| 2131 | fprintf(f, " = "); |
| 2132 | this->fill_->print(f); |
| 2133 | } |
| 2134 | |
| 2135 | if (this->phdrs_ != NULL) |
| 2136 | { |
| 2137 | for (String_list::const_iterator p = this->phdrs_->begin(); |
| 2138 | p != this->phdrs_->end(); |
| 2139 | ++p) |
| 2140 | fprintf(f, " :%s", p->c_str()); |
| 2141 | } |
| 2142 | |
| 2143 | fprintf(f, "\n"); |
| 2144 | } |
| 2145 | |
| 2146 | // An output section created to hold orphaned input sections. These |
| 2147 | // do not actually appear in linker scripts. However, for convenience |
| 2148 | // when setting the output section addresses, we put a marker to these |
| 2149 | // sections in the appropriate place in the list of SECTIONS elements. |
| 2150 | |
| 2151 | class Orphan_output_section : public Sections_element |
| 2152 | { |
| 2153 | public: |
| 2154 | Orphan_output_section(Output_section* os) |
| 2155 | : os_(os) |
| 2156 | { } |
| 2157 | |
| 2158 | // Return whether the orphan output section is relro. We can just |
| 2159 | // check the output section because we always set the flag, if |
| 2160 | // needed, just after we create the Orphan_output_section. |
| 2161 | bool |
| 2162 | is_relro() const |
| 2163 | { return this->os_->is_relro(); } |
| 2164 | |
| 2165 | // Initialize OSP with an output section. This should have been |
| 2166 | // done already. |
| 2167 | void |
| 2168 | orphan_section_init(Orphan_section_placement*, |
| 2169 | Script_sections::Elements_iterator) |
| 2170 | { gold_unreachable(); } |
| 2171 | |
| 2172 | // Set section addresses. |
| 2173 | void |
| 2174 | set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*); |
| 2175 | |
| 2176 | // Get the list of segments to use for an allocated section when |
| 2177 | // using a PHDRS clause. |
| 2178 | Output_section* |
| 2179 | allocate_to_segment(String_list**, bool*); |
| 2180 | |
| 2181 | // Return the associated Output_section. |
| 2182 | Output_section* |
| 2183 | get_output_section() const |
| 2184 | { return this->os_; } |
| 2185 | |
| 2186 | // Print for debugging. |
| 2187 | void |
| 2188 | print(FILE* f) const |
| 2189 | { |
| 2190 | fprintf(f, " marker for orphaned output section %s\n", |
| 2191 | this->os_->name()); |
| 2192 | } |
| 2193 | |
| 2194 | private: |
| 2195 | Output_section* os_; |
| 2196 | }; |
| 2197 | |
| 2198 | // Set section addresses. |
| 2199 | |
| 2200 | void |
| 2201 | Orphan_output_section::set_section_addresses(Symbol_table*, Layout*, |
| 2202 | uint64_t* dot_value, |
| 2203 | uint64_t* load_address) |
| 2204 | { |
| 2205 | typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list; |
| 2206 | |
| 2207 | bool have_load_address = *load_address != *dot_value; |
| 2208 | |
| 2209 | uint64_t address = *dot_value; |
| 2210 | address = align_address(address, this->os_->addralign()); |
| 2211 | |
| 2212 | if ((this->os_->flags() & elfcpp::SHF_ALLOC) != 0) |
| 2213 | { |
| 2214 | this->os_->set_address(address); |
| 2215 | if (have_load_address) |
| 2216 | this->os_->set_load_address(align_address(*load_address, |
| 2217 | this->os_->addralign())); |
| 2218 | } |
| 2219 | |
| 2220 | Input_section_list input_sections; |
| 2221 | address += this->os_->get_input_sections(address, "", &input_sections); |
| 2222 | |
| 2223 | for (Input_section_list::iterator p = input_sections.begin(); |
| 2224 | p != input_sections.end(); |
| 2225 | ++p) |
| 2226 | { |
| 2227 | uint64_t addralign; |
| 2228 | uint64_t size; |
| 2229 | |
| 2230 | // We know what are single-threaded, so it is OK to lock the |
| 2231 | // object. |
| 2232 | { |
| 2233 | const Task* task = reinterpret_cast<const Task*>(-1); |
| 2234 | Task_lock_obj<Object> tl(task, p->first); |
| 2235 | addralign = p->first->section_addralign(p->second); |
| 2236 | size = p->first->section_size(p->second); |
| 2237 | } |
| 2238 | |
| 2239 | address = align_address(address, addralign); |
| 2240 | this->os_->add_input_section_for_script(p->first, p->second, size, |
| 2241 | addralign); |
| 2242 | address += size; |
| 2243 | } |
| 2244 | |
| 2245 | if (!have_load_address) |
| 2246 | *load_address = address; |
| 2247 | else |
| 2248 | *load_address += address - *dot_value; |
| 2249 | |
| 2250 | *dot_value = address; |
| 2251 | } |
| 2252 | |
| 2253 | // Get the list of segments to use for an allocated section when using |
| 2254 | // a PHDRS clause. If this is an allocated section, return the |
| 2255 | // Output_section. We don't change the list of segments. |
| 2256 | |
| 2257 | Output_section* |
| 2258 | Orphan_output_section::allocate_to_segment(String_list**, bool* orphan) |
| 2259 | { |
| 2260 | if ((this->os_->flags() & elfcpp::SHF_ALLOC) == 0) |
| 2261 | return NULL; |
| 2262 | *orphan = true; |
| 2263 | return this->os_; |
| 2264 | } |
| 2265 | |
| 2266 | // Class Phdrs_element. A program header from a PHDRS clause. |
| 2267 | |
| 2268 | class Phdrs_element |
| 2269 | { |
| 2270 | public: |
| 2271 | Phdrs_element(const char* name, size_t namelen, unsigned int type, |
| 2272 | bool includes_filehdr, bool includes_phdrs, |
| 2273 | bool is_flags_valid, unsigned int flags, |
| 2274 | Expression* load_address) |
| 2275 | : name_(name, namelen), type_(type), includes_filehdr_(includes_filehdr), |
| 2276 | includes_phdrs_(includes_phdrs), is_flags_valid_(is_flags_valid), |
| 2277 | flags_(flags), load_address_(load_address), load_address_value_(0), |
| 2278 | segment_(NULL) |
| 2279 | { } |
| 2280 | |
| 2281 | // Return the name of this segment. |
| 2282 | const std::string& |
| 2283 | name() const |
| 2284 | { return this->name_; } |
| 2285 | |
| 2286 | // Return the type of the segment. |
| 2287 | unsigned int |
| 2288 | type() const |
| 2289 | { return this->type_; } |
| 2290 | |
| 2291 | // Whether to include the file header. |
| 2292 | bool |
| 2293 | includes_filehdr() const |
| 2294 | { return this->includes_filehdr_; } |
| 2295 | |
| 2296 | // Whether to include the program headers. |
| 2297 | bool |
| 2298 | includes_phdrs() const |
| 2299 | { return this->includes_phdrs_; } |
| 2300 | |
| 2301 | // Return whether there is a load address. |
| 2302 | bool |
| 2303 | has_load_address() const |
| 2304 | { return this->load_address_ != NULL; } |
| 2305 | |
| 2306 | // Evaluate the load address expression if there is one. |
| 2307 | void |
| 2308 | eval_load_address(Symbol_table* symtab, Layout* layout) |
| 2309 | { |
| 2310 | if (this->load_address_ != NULL) |
| 2311 | this->load_address_value_ = this->load_address_->eval(symtab, layout, |
| 2312 | true); |
| 2313 | } |
| 2314 | |
| 2315 | // Return the load address. |
| 2316 | uint64_t |
| 2317 | load_address() const |
| 2318 | { |
| 2319 | gold_assert(this->load_address_ != NULL); |
| 2320 | return this->load_address_value_; |
| 2321 | } |
| 2322 | |
| 2323 | // Create the segment. |
| 2324 | Output_segment* |
| 2325 | create_segment(Layout* layout) |
| 2326 | { |
| 2327 | this->segment_ = layout->make_output_segment(this->type_, this->flags_); |
| 2328 | return this->segment_; |
| 2329 | } |
| 2330 | |
| 2331 | // Return the segment. |
| 2332 | Output_segment* |
| 2333 | segment() |
| 2334 | { return this->segment_; } |
| 2335 | |
| 2336 | // Set the segment flags if appropriate. |
| 2337 | void |
| 2338 | set_flags_if_valid() |
| 2339 | { |
| 2340 | if (this->is_flags_valid_) |
| 2341 | this->segment_->set_flags(this->flags_); |
| 2342 | } |
| 2343 | |
| 2344 | // Print for debugging. |
| 2345 | void |
| 2346 | print(FILE*) const; |
| 2347 | |
| 2348 | private: |
| 2349 | // The name used in the script. |
| 2350 | std::string name_; |
| 2351 | // The type of the segment (PT_LOAD, etc.). |
| 2352 | unsigned int type_; |
| 2353 | // Whether this segment includes the file header. |
| 2354 | bool includes_filehdr_; |
| 2355 | // Whether this segment includes the section headers. |
| 2356 | bool includes_phdrs_; |
| 2357 | // Whether the flags were explicitly specified. |
| 2358 | bool is_flags_valid_; |
| 2359 | // The flags for this segment (PF_R, etc.) if specified. |
| 2360 | unsigned int flags_; |
| 2361 | // The expression for the load address for this segment. This may |
| 2362 | // be NULL. |
| 2363 | Expression* load_address_; |
| 2364 | // The actual load address from evaluating the expression. |
| 2365 | uint64_t load_address_value_; |
| 2366 | // The segment itself. |
| 2367 | Output_segment* segment_; |
| 2368 | }; |
| 2369 | |
| 2370 | // Print for debugging. |
| 2371 | |
| 2372 | void |
| 2373 | Phdrs_element::print(FILE* f) const |
| 2374 | { |
| 2375 | fprintf(f, " %s 0x%x", this->name_.c_str(), this->type_); |
| 2376 | if (this->includes_filehdr_) |
| 2377 | fprintf(f, " FILEHDR"); |
| 2378 | if (this->includes_phdrs_) |
| 2379 | fprintf(f, " PHDRS"); |
| 2380 | if (this->is_flags_valid_) |
| 2381 | fprintf(f, " FLAGS(%u)", this->flags_); |
| 2382 | if (this->load_address_ != NULL) |
| 2383 | { |
| 2384 | fprintf(f, " AT("); |
| 2385 | this->load_address_->print(f); |
| 2386 | fprintf(f, ")"); |
| 2387 | } |
| 2388 | fprintf(f, ";\n"); |
| 2389 | } |
| 2390 | |
| 2391 | // Class Script_sections. |
| 2392 | |
| 2393 | Script_sections::Script_sections() |
| 2394 | : saw_sections_clause_(false), |
| 2395 | in_sections_clause_(false), |
| 2396 | sections_elements_(NULL), |
| 2397 | output_section_(NULL), |
| 2398 | phdrs_elements_(NULL), |
| 2399 | orphan_section_placement_(NULL), |
| 2400 | data_segment_align_start_(), |
| 2401 | saw_data_segment_align_(false), |
| 2402 | saw_relro_end_(false) |
| 2403 | { |
| 2404 | } |
| 2405 | |
| 2406 | // Start a SECTIONS clause. |
| 2407 | |
| 2408 | void |
| 2409 | Script_sections::start_sections() |
| 2410 | { |
| 2411 | gold_assert(!this->in_sections_clause_ && this->output_section_ == NULL); |
| 2412 | this->saw_sections_clause_ = true; |
| 2413 | this->in_sections_clause_ = true; |
| 2414 | if (this->sections_elements_ == NULL) |
| 2415 | this->sections_elements_ = new Sections_elements; |
| 2416 | } |
| 2417 | |
| 2418 | // Finish a SECTIONS clause. |
| 2419 | |
| 2420 | void |
| 2421 | Script_sections::finish_sections() |
| 2422 | { |
| 2423 | gold_assert(this->in_sections_clause_ && this->output_section_ == NULL); |
| 2424 | this->in_sections_clause_ = false; |
| 2425 | } |
| 2426 | |
| 2427 | // Add a symbol to be defined. |
| 2428 | |
| 2429 | void |
| 2430 | Script_sections::add_symbol_assignment(const char* name, size_t length, |
| 2431 | Expression* val, bool provide, |
| 2432 | bool hidden) |
| 2433 | { |
| 2434 | if (this->output_section_ != NULL) |
| 2435 | this->output_section_->add_symbol_assignment(name, length, val, |
| 2436 | provide, hidden); |
| 2437 | else |
| 2438 | { |
| 2439 | Sections_element* p = new Sections_element_assignment(name, length, |
| 2440 | val, provide, |
| 2441 | hidden); |
| 2442 | this->sections_elements_->push_back(p); |
| 2443 | } |
| 2444 | } |
| 2445 | |
| 2446 | // Add an assignment to the special dot symbol. |
| 2447 | |
| 2448 | void |
| 2449 | Script_sections::add_dot_assignment(Expression* val) |
| 2450 | { |
| 2451 | if (this->output_section_ != NULL) |
| 2452 | this->output_section_->add_dot_assignment(val); |
| 2453 | else |
| 2454 | { |
| 2455 | Sections_element* p = new Sections_element_dot_assignment(val); |
| 2456 | this->sections_elements_->push_back(p); |
| 2457 | } |
| 2458 | } |
| 2459 | |
| 2460 | // Add an assertion. |
| 2461 | |
| 2462 | void |
| 2463 | Script_sections::add_assertion(Expression* check, const char* message, |
| 2464 | size_t messagelen) |
| 2465 | { |
| 2466 | if (this->output_section_ != NULL) |
| 2467 | this->output_section_->add_assertion(check, message, messagelen); |
| 2468 | else |
| 2469 | { |
| 2470 | Sections_element* p = new Sections_element_assertion(check, message, |
| 2471 | messagelen); |
| 2472 | this->sections_elements_->push_back(p); |
| 2473 | } |
| 2474 | } |
| 2475 | |
| 2476 | // Start processing entries for an output section. |
| 2477 | |
| 2478 | void |
| 2479 | Script_sections::start_output_section( |
| 2480 | const char* name, |
| 2481 | size_t namelen, |
| 2482 | const Parser_output_section_header *header) |
| 2483 | { |
| 2484 | Output_section_definition* posd = new Output_section_definition(name, |
| 2485 | namelen, |
| 2486 | header); |
| 2487 | this->sections_elements_->push_back(posd); |
| 2488 | gold_assert(this->output_section_ == NULL); |
| 2489 | this->output_section_ = posd; |
| 2490 | } |
| 2491 | |
| 2492 | // Stop processing entries for an output section. |
| 2493 | |
| 2494 | void |
| 2495 | Script_sections::finish_output_section( |
| 2496 | const Parser_output_section_trailer* trailer) |
| 2497 | { |
| 2498 | gold_assert(this->output_section_ != NULL); |
| 2499 | this->output_section_->finish(trailer); |
| 2500 | this->output_section_ = NULL; |
| 2501 | } |
| 2502 | |
| 2503 | // Add a data item to the current output section. |
| 2504 | |
| 2505 | void |
| 2506 | Script_sections::add_data(int size, bool is_signed, Expression* val) |
| 2507 | { |
| 2508 | gold_assert(this->output_section_ != NULL); |
| 2509 | this->output_section_->add_data(size, is_signed, val); |
| 2510 | } |
| 2511 | |
| 2512 | // Add a fill value setting to the current output section. |
| 2513 | |
| 2514 | void |
| 2515 | Script_sections::add_fill(Expression* val) |
| 2516 | { |
| 2517 | gold_assert(this->output_section_ != NULL); |
| 2518 | this->output_section_->add_fill(val); |
| 2519 | } |
| 2520 | |
| 2521 | // Add an input section specification to the current output section. |
| 2522 | |
| 2523 | void |
| 2524 | Script_sections::add_input_section(const Input_section_spec* spec, bool keep) |
| 2525 | { |
| 2526 | gold_assert(this->output_section_ != NULL); |
| 2527 | this->output_section_->add_input_section(spec, keep); |
| 2528 | } |
| 2529 | |
| 2530 | // This is called when we see DATA_SEGMENT_ALIGN. It means that any |
| 2531 | // subsequent output sections may be relro. |
| 2532 | |
| 2533 | void |
| 2534 | Script_sections::data_segment_align() |
| 2535 | { |
| 2536 | if (this->saw_data_segment_align_) |
| 2537 | gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script")); |
| 2538 | gold_assert(!this->sections_elements_->empty()); |
| 2539 | Sections_elements::iterator p = this->sections_elements_->end(); |
| 2540 | --p; |
| 2541 | this->data_segment_align_start_ = p; |
| 2542 | this->saw_data_segment_align_ = true; |
| 2543 | } |
| 2544 | |
| 2545 | // This is called when we see DATA_SEGMENT_RELRO_END. It means that |
| 2546 | // any output sections seen since DATA_SEGMENT_ALIGN are relro. |
| 2547 | |
| 2548 | void |
| 2549 | Script_sections::data_segment_relro_end() |
| 2550 | { |
| 2551 | if (this->saw_relro_end_) |
| 2552 | gold_error(_("DATA_SEGMENT_RELRO_END may only appear once " |
| 2553 | "in a linker script")); |
| 2554 | this->saw_relro_end_ = true; |
| 2555 | |
| 2556 | if (!this->saw_data_segment_align_) |
| 2557 | gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN")); |
| 2558 | else |
| 2559 | { |
| 2560 | Sections_elements::iterator p = this->data_segment_align_start_; |
| 2561 | for (++p; p != this->sections_elements_->end(); ++p) |
| 2562 | (*p)->set_is_relro(); |
| 2563 | } |
| 2564 | } |
| 2565 | |
| 2566 | // Create any required sections. |
| 2567 | |
| 2568 | void |
| 2569 | Script_sections::create_sections(Layout* layout) |
| 2570 | { |
| 2571 | if (!this->saw_sections_clause_) |
| 2572 | return; |
| 2573 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2574 | p != this->sections_elements_->end(); |
| 2575 | ++p) |
| 2576 | (*p)->create_sections(layout); |
| 2577 | } |
| 2578 | |
| 2579 | // Add any symbols we are defining to the symbol table. |
| 2580 | |
| 2581 | void |
| 2582 | Script_sections::add_symbols_to_table(Symbol_table* symtab) |
| 2583 | { |
| 2584 | if (!this->saw_sections_clause_) |
| 2585 | return; |
| 2586 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2587 | p != this->sections_elements_->end(); |
| 2588 | ++p) |
| 2589 | (*p)->add_symbols_to_table(symtab); |
| 2590 | } |
| 2591 | |
| 2592 | // Finalize symbols and check assertions. |
| 2593 | |
| 2594 | void |
| 2595 | Script_sections::finalize_symbols(Symbol_table* symtab, const Layout* layout) |
| 2596 | { |
| 2597 | if (!this->saw_sections_clause_) |
| 2598 | return; |
| 2599 | uint64_t dot_value = 0; |
| 2600 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2601 | p != this->sections_elements_->end(); |
| 2602 | ++p) |
| 2603 | (*p)->finalize_symbols(symtab, layout, &dot_value); |
| 2604 | } |
| 2605 | |
| 2606 | // Return the name of the output section to use for an input file name |
| 2607 | // and section name. |
| 2608 | |
| 2609 | const char* |
| 2610 | Script_sections::output_section_name(const char* file_name, |
| 2611 | const char* section_name, |
| 2612 | Output_section*** output_section_slot) |
| 2613 | { |
| 2614 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 2615 | p != this->sections_elements_->end(); |
| 2616 | ++p) |
| 2617 | { |
| 2618 | const char* ret = (*p)->output_section_name(file_name, section_name, |
| 2619 | output_section_slot); |
| 2620 | |
| 2621 | if (ret != NULL) |
| 2622 | { |
| 2623 | // The special name /DISCARD/ means that the input section |
| 2624 | // should be discarded. |
| 2625 | if (strcmp(ret, "/DISCARD/") == 0) |
| 2626 | { |
| 2627 | *output_section_slot = NULL; |
| 2628 | return NULL; |
| 2629 | } |
| 2630 | return ret; |
| 2631 | } |
| 2632 | } |
| 2633 | |
| 2634 | // If we couldn't find a mapping for the name, the output section |
| 2635 | // gets the name of the input section. |
| 2636 | |
| 2637 | *output_section_slot = NULL; |
| 2638 | |
| 2639 | return section_name; |
| 2640 | } |
| 2641 | |
| 2642 | // Place a marker for an orphan output section into the SECTIONS |
| 2643 | // clause. |
| 2644 | |
| 2645 | void |
| 2646 | Script_sections::place_orphan(Output_section* os) |
| 2647 | { |
| 2648 | Orphan_section_placement* osp = this->orphan_section_placement_; |
| 2649 | if (osp == NULL) |
| 2650 | { |
| 2651 | // Initialize the Orphan_section_placement structure. |
| 2652 | osp = new Orphan_section_placement(); |
| 2653 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2654 | p != this->sections_elements_->end(); |
| 2655 | ++p) |
| 2656 | (*p)->orphan_section_init(osp, p); |
| 2657 | gold_assert(!this->sections_elements_->empty()); |
| 2658 | Sections_elements::iterator last = this->sections_elements_->end(); |
| 2659 | --last; |
| 2660 | osp->last_init(last); |
| 2661 | this->orphan_section_placement_ = osp; |
| 2662 | } |
| 2663 | |
| 2664 | Orphan_output_section* orphan = new Orphan_output_section(os); |
| 2665 | |
| 2666 | // Look for where to put ORPHAN. |
| 2667 | Sections_elements::iterator* where; |
| 2668 | if (osp->find_place(os, &where)) |
| 2669 | { |
| 2670 | if ((**where)->is_relro()) |
| 2671 | os->set_is_relro(); |
| 2672 | else |
| 2673 | os->clear_is_relro(); |
| 2674 | |
| 2675 | // We want to insert ORPHAN after *WHERE, and then update *WHERE |
| 2676 | // so that the next one goes after this one. |
| 2677 | Sections_elements::iterator p = *where; |
| 2678 | gold_assert(p != this->sections_elements_->end()); |
| 2679 | ++p; |
| 2680 | *where = this->sections_elements_->insert(p, orphan); |
| 2681 | } |
| 2682 | else |
| 2683 | { |
| 2684 | os->clear_is_relro(); |
| 2685 | // We don't have a place to put this orphan section. Put it, |
| 2686 | // and all other sections like it, at the end, but before the |
| 2687 | // sections which always come at the end. |
| 2688 | Sections_elements::iterator last = osp->last_place(); |
| 2689 | *where = this->sections_elements_->insert(last, orphan); |
| 2690 | } |
| 2691 | } |
| 2692 | |
| 2693 | // Set the addresses of all the output sections. Walk through all the |
| 2694 | // elements, tracking the dot symbol. Apply assignments which set |
| 2695 | // absolute symbol values, in case they are used when setting dot. |
| 2696 | // Fill in data statement values. As we find output sections, set the |
| 2697 | // address, set the address of all associated input sections, and |
| 2698 | // update dot. Return the segment which should hold the file header |
| 2699 | // and segment headers, if any. |
| 2700 | |
| 2701 | Output_segment* |
| 2702 | Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout) |
| 2703 | { |
| 2704 | gold_assert(this->saw_sections_clause_); |
| 2705 | |
| 2706 | // Implement ONLY_IF_RO/ONLY_IF_RW constraints. These are a pain |
| 2707 | // for our representation. |
| 2708 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2709 | p != this->sections_elements_->end(); |
| 2710 | ++p) |
| 2711 | { |
| 2712 | Output_section_definition* posd; |
| 2713 | Section_constraint failed_constraint = (*p)->check_constraint(&posd); |
| 2714 | if (failed_constraint != CONSTRAINT_NONE) |
| 2715 | { |
| 2716 | Sections_elements::iterator q; |
| 2717 | for (q = this->sections_elements_->begin(); |
| 2718 | q != this->sections_elements_->end(); |
| 2719 | ++q) |
| 2720 | { |
| 2721 | if (q != p) |
| 2722 | { |
| 2723 | if ((*q)->alternate_constraint(posd, failed_constraint)) |
| 2724 | break; |
| 2725 | } |
| 2726 | } |
| 2727 | |
| 2728 | if (q == this->sections_elements_->end()) |
| 2729 | gold_error(_("no matching section constraint")); |
| 2730 | } |
| 2731 | } |
| 2732 | |
| 2733 | // Force the alignment of the first TLS section to be the maximum |
| 2734 | // alignment of all TLS sections. |
| 2735 | Output_section* first_tls = NULL; |
| 2736 | uint64_t tls_align = 0; |
| 2737 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 2738 | p != this->sections_elements_->end(); |
| 2739 | ++p) |
| 2740 | { |
| 2741 | Output_section *os = (*p)->get_output_section(); |
| 2742 | if (os != NULL && (os->flags() & elfcpp::SHF_TLS) != 0) |
| 2743 | { |
| 2744 | if (first_tls == NULL) |
| 2745 | first_tls = os; |
| 2746 | if (os->addralign() > tls_align) |
| 2747 | tls_align = os->addralign(); |
| 2748 | } |
| 2749 | } |
| 2750 | if (first_tls != NULL) |
| 2751 | first_tls->set_addralign(tls_align); |
| 2752 | |
| 2753 | // For a relocatable link, we implicitly set dot to zero. |
| 2754 | uint64_t dot_value = 0; |
| 2755 | uint64_t load_address = 0; |
| 2756 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2757 | p != this->sections_elements_->end(); |
| 2758 | ++p) |
| 2759 | (*p)->set_section_addresses(symtab, layout, &dot_value, &load_address); |
| 2760 | |
| 2761 | if (this->phdrs_elements_ != NULL) |
| 2762 | { |
| 2763 | for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| 2764 | p != this->phdrs_elements_->end(); |
| 2765 | ++p) |
| 2766 | (*p)->eval_load_address(symtab, layout); |
| 2767 | } |
| 2768 | |
| 2769 | return this->create_segments(layout); |
| 2770 | } |
| 2771 | |
| 2772 | // Sort the sections in order to put them into segments. |
| 2773 | |
| 2774 | class Sort_output_sections |
| 2775 | { |
| 2776 | public: |
| 2777 | bool |
| 2778 | operator()(const Output_section* os1, const Output_section* os2) const; |
| 2779 | }; |
| 2780 | |
| 2781 | bool |
| 2782 | Sort_output_sections::operator()(const Output_section* os1, |
| 2783 | const Output_section* os2) const |
| 2784 | { |
| 2785 | // Sort first by the load address. |
| 2786 | uint64_t lma1 = (os1->has_load_address() |
| 2787 | ? os1->load_address() |
| 2788 | : os1->address()); |
| 2789 | uint64_t lma2 = (os2->has_load_address() |
| 2790 | ? os2->load_address() |
| 2791 | : os2->address()); |
| 2792 | if (lma1 != lma2) |
| 2793 | return lma1 < lma2; |
| 2794 | |
| 2795 | // Then sort by the virtual address. |
| 2796 | if (os1->address() != os2->address()) |
| 2797 | return os1->address() < os2->address(); |
| 2798 | |
| 2799 | // Sort TLS sections to the end. |
| 2800 | bool tls1 = (os1->flags() & elfcpp::SHF_TLS) != 0; |
| 2801 | bool tls2 = (os2->flags() & elfcpp::SHF_TLS) != 0; |
| 2802 | if (tls1 != tls2) |
| 2803 | return tls2; |
| 2804 | |
| 2805 | // Sort PROGBITS before NOBITS. |
| 2806 | if (os1->type() == elfcpp::SHT_PROGBITS && os2->type() == elfcpp::SHT_NOBITS) |
| 2807 | return true; |
| 2808 | if (os1->type() == elfcpp::SHT_NOBITS && os2->type() == elfcpp::SHT_PROGBITS) |
| 2809 | return false; |
| 2810 | |
| 2811 | // Otherwise we don't care. |
| 2812 | return false; |
| 2813 | } |
| 2814 | |
| 2815 | // Return whether OS is a BSS section. This is a SHT_NOBITS section. |
| 2816 | // We treat a section with the SHF_TLS flag set as taking up space |
| 2817 | // even if it is SHT_NOBITS (this is true of .tbss), as we allocate |
| 2818 | // space for them in the file. |
| 2819 | |
| 2820 | bool |
| 2821 | Script_sections::is_bss_section(const Output_section* os) |
| 2822 | { |
| 2823 | return (os->type() == elfcpp::SHT_NOBITS |
| 2824 | && (os->flags() & elfcpp::SHF_TLS) == 0); |
| 2825 | } |
| 2826 | |
| 2827 | // Return the size taken by the file header and the program headers. |
| 2828 | |
| 2829 | size_t |
| 2830 | Script_sections::total_header_size(Layout* layout) const |
| 2831 | { |
| 2832 | size_t segment_count = layout->segment_count(); |
| 2833 | size_t file_header_size; |
| 2834 | size_t segment_headers_size; |
| 2835 | if (parameters->target().get_size() == 32) |
| 2836 | { |
| 2837 | file_header_size = elfcpp::Elf_sizes<32>::ehdr_size; |
| 2838 | segment_headers_size = segment_count * elfcpp::Elf_sizes<32>::phdr_size; |
| 2839 | } |
| 2840 | else if (parameters->target().get_size() == 64) |
| 2841 | { |
| 2842 | file_header_size = elfcpp::Elf_sizes<64>::ehdr_size; |
| 2843 | segment_headers_size = segment_count * elfcpp::Elf_sizes<64>::phdr_size; |
| 2844 | } |
| 2845 | else |
| 2846 | gold_unreachable(); |
| 2847 | |
| 2848 | return file_header_size + segment_headers_size; |
| 2849 | } |
| 2850 | |
| 2851 | // Return the amount we have to subtract from the LMA to accomodate |
| 2852 | // headers of the given size. The complication is that the file |
| 2853 | // header have to be at the start of a page, as otherwise it will not |
| 2854 | // be at the start of the file. |
| 2855 | |
| 2856 | uint64_t |
| 2857 | Script_sections::header_size_adjustment(uint64_t lma, |
| 2858 | size_t sizeof_headers) const |
| 2859 | { |
| 2860 | const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| 2861 | uint64_t hdr_lma = lma - sizeof_headers; |
| 2862 | hdr_lma &= ~(abi_pagesize - 1); |
| 2863 | return lma - hdr_lma; |
| 2864 | } |
| 2865 | |
| 2866 | // Create the PT_LOAD segments when using a SECTIONS clause. Returns |
| 2867 | // the segment which should hold the file header and segment headers, |
| 2868 | // if any. |
| 2869 | |
| 2870 | Output_segment* |
| 2871 | Script_sections::create_segments(Layout* layout) |
| 2872 | { |
| 2873 | gold_assert(this->saw_sections_clause_); |
| 2874 | |
| 2875 | if (parameters->options().relocatable()) |
| 2876 | return NULL; |
| 2877 | |
| 2878 | if (this->saw_phdrs_clause()) |
| 2879 | return create_segments_from_phdrs_clause(layout); |
| 2880 | |
| 2881 | Layout::Section_list sections; |
| 2882 | layout->get_allocated_sections(§ions); |
| 2883 | |
| 2884 | // Sort the sections by address. |
| 2885 | std::stable_sort(sections.begin(), sections.end(), Sort_output_sections()); |
| 2886 | |
| 2887 | this->create_note_and_tls_segments(layout, §ions); |
| 2888 | |
| 2889 | // Walk through the sections adding them to PT_LOAD segments. |
| 2890 | const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| 2891 | Output_segment* first_seg = NULL; |
| 2892 | Output_segment* current_seg = NULL; |
| 2893 | bool is_current_seg_readonly = true; |
| 2894 | Layout::Section_list::iterator plast = sections.end(); |
| 2895 | uint64_t last_vma = 0; |
| 2896 | uint64_t last_lma = 0; |
| 2897 | uint64_t last_size = 0; |
| 2898 | for (Layout::Section_list::iterator p = sections.begin(); |
| 2899 | p != sections.end(); |
| 2900 | ++p) |
| 2901 | { |
| 2902 | const uint64_t vma = (*p)->address(); |
| 2903 | const uint64_t lma = ((*p)->has_load_address() |
| 2904 | ? (*p)->load_address() |
| 2905 | : vma); |
| 2906 | const uint64_t size = (*p)->current_data_size(); |
| 2907 | |
| 2908 | bool need_new_segment; |
| 2909 | if (current_seg == NULL) |
| 2910 | need_new_segment = true; |
| 2911 | else if (lma - vma != last_lma - last_vma) |
| 2912 | { |
| 2913 | // This section has a different LMA relationship than the |
| 2914 | // last one; we need a new segment. |
| 2915 | need_new_segment = true; |
| 2916 | } |
| 2917 | else if (align_address(last_lma + last_size, abi_pagesize) |
| 2918 | < align_address(lma, abi_pagesize)) |
| 2919 | { |
| 2920 | // Putting this section in the segment would require |
| 2921 | // skipping a page. |
| 2922 | need_new_segment = true; |
| 2923 | } |
| 2924 | else if (is_bss_section(*plast) && !is_bss_section(*p)) |
| 2925 | { |
| 2926 | // A non-BSS section can not follow a BSS section in the |
| 2927 | // same segment. |
| 2928 | need_new_segment = true; |
| 2929 | } |
| 2930 | else if (is_current_seg_readonly |
| 2931 | && ((*p)->flags() & elfcpp::SHF_WRITE) != 0 |
| 2932 | && !parameters->options().omagic()) |
| 2933 | { |
| 2934 | // Don't put a writable section in the same segment as a |
| 2935 | // non-writable section. |
| 2936 | need_new_segment = true; |
| 2937 | } |
| 2938 | else |
| 2939 | { |
| 2940 | // Otherwise, reuse the existing segment. |
| 2941 | need_new_segment = false; |
| 2942 | } |
| 2943 | |
| 2944 | elfcpp::Elf_Word seg_flags = |
| 2945 | Layout::section_flags_to_segment((*p)->flags()); |
| 2946 | |
| 2947 | if (need_new_segment) |
| 2948 | { |
| 2949 | current_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| 2950 | seg_flags); |
| 2951 | current_seg->set_addresses(vma, lma); |
| 2952 | if (first_seg == NULL) |
| 2953 | first_seg = current_seg; |
| 2954 | is_current_seg_readonly = true; |
| 2955 | } |
| 2956 | |
| 2957 | current_seg->add_output_section(*p, seg_flags); |
| 2958 | |
| 2959 | if (((*p)->flags() & elfcpp::SHF_WRITE) != 0) |
| 2960 | is_current_seg_readonly = false; |
| 2961 | |
| 2962 | plast = p; |
| 2963 | last_vma = vma; |
| 2964 | last_lma = lma; |
| 2965 | last_size = size; |
| 2966 | } |
| 2967 | |
| 2968 | // An ELF program should work even if the program headers are not in |
| 2969 | // a PT_LOAD segment. However, it appears that the Linux kernel |
| 2970 | // does not set the AT_PHDR auxiliary entry in that case. It sets |
| 2971 | // the load address to p_vaddr - p_offset of the first PT_LOAD |
| 2972 | // segment. It then sets AT_PHDR to the load address plus the |
| 2973 | // offset to the program headers, e_phoff in the file header. This |
| 2974 | // fails when the program headers appear in the file before the |
| 2975 | // first PT_LOAD segment. Therefore, we always create a PT_LOAD |
| 2976 | // segment to hold the file header and the program headers. This is |
| 2977 | // effectively what the GNU linker does, and it is slightly more |
| 2978 | // efficient in any case. We try to use the first PT_LOAD segment |
| 2979 | // if we can, otherwise we make a new one. |
| 2980 | |
| 2981 | if (first_seg == NULL) |
| 2982 | return NULL; |
| 2983 | |
| 2984 | size_t sizeof_headers = this->total_header_size(layout); |
| 2985 | |
| 2986 | uint64_t vma = first_seg->vaddr(); |
| 2987 | uint64_t lma = first_seg->paddr(); |
| 2988 | |
| 2989 | uint64_t subtract = this->header_size_adjustment(lma, sizeof_headers); |
| 2990 | |
| 2991 | if ((lma & (abi_pagesize - 1)) >= sizeof_headers) |
| 2992 | { |
| 2993 | first_seg->set_addresses(vma - subtract, lma - subtract); |
| 2994 | return first_seg; |
| 2995 | } |
| 2996 | |
| 2997 | // If there is no room to squeeze in the headers, then punt. The |
| 2998 | // resulting executable probably won't run on GNU/Linux, but we |
| 2999 | // trust that the user knows what they are doing. |
| 3000 | if (lma < subtract || vma < subtract) |
| 3001 | return NULL; |
| 3002 | |
| 3003 | Output_segment* load_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| 3004 | elfcpp::PF_R); |
| 3005 | load_seg->set_addresses(vma - subtract, lma - subtract); |
| 3006 | |
| 3007 | return load_seg; |
| 3008 | } |
| 3009 | |
| 3010 | // Create a PT_NOTE segment for each SHT_NOTE section and a PT_TLS |
| 3011 | // segment if there are any SHT_TLS sections. |
| 3012 | |
| 3013 | void |
| 3014 | Script_sections::create_note_and_tls_segments( |
| 3015 | Layout* layout, |
| 3016 | const Layout::Section_list* sections) |
| 3017 | { |
| 3018 | gold_assert(!this->saw_phdrs_clause()); |
| 3019 | |
| 3020 | bool saw_tls = false; |
| 3021 | for (Layout::Section_list::const_iterator p = sections->begin(); |
| 3022 | p != sections->end(); |
| 3023 | ++p) |
| 3024 | { |
| 3025 | if ((*p)->type() == elfcpp::SHT_NOTE) |
| 3026 | { |
| 3027 | elfcpp::Elf_Word seg_flags = |
| 3028 | Layout::section_flags_to_segment((*p)->flags()); |
| 3029 | Output_segment* oseg = layout->make_output_segment(elfcpp::PT_NOTE, |
| 3030 | seg_flags); |
| 3031 | oseg->add_output_section(*p, seg_flags); |
| 3032 | |
| 3033 | // Incorporate any subsequent SHT_NOTE sections, in the |
| 3034 | // hopes that the script is sensible. |
| 3035 | Layout::Section_list::const_iterator pnext = p + 1; |
| 3036 | while (pnext != sections->end() |
| 3037 | && (*pnext)->type() == elfcpp::SHT_NOTE) |
| 3038 | { |
| 3039 | seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| 3040 | oseg->add_output_section(*pnext, seg_flags); |
| 3041 | p = pnext; |
| 3042 | ++pnext; |
| 3043 | } |
| 3044 | } |
| 3045 | |
| 3046 | if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| 3047 | { |
| 3048 | if (saw_tls) |
| 3049 | gold_error(_("TLS sections are not adjacent")); |
| 3050 | |
| 3051 | elfcpp::Elf_Word seg_flags = |
| 3052 | Layout::section_flags_to_segment((*p)->flags()); |
| 3053 | Output_segment* oseg = layout->make_output_segment(elfcpp::PT_TLS, |
| 3054 | seg_flags); |
| 3055 | oseg->add_output_section(*p, seg_flags); |
| 3056 | |
| 3057 | Layout::Section_list::const_iterator pnext = p + 1; |
| 3058 | while (pnext != sections->end() |
| 3059 | && ((*pnext)->flags() & elfcpp::SHF_TLS) != 0) |
| 3060 | { |
| 3061 | seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| 3062 | oseg->add_output_section(*pnext, seg_flags); |
| 3063 | p = pnext; |
| 3064 | ++pnext; |
| 3065 | } |
| 3066 | |
| 3067 | saw_tls = true; |
| 3068 | } |
| 3069 | } |
| 3070 | } |
| 3071 | |
| 3072 | // Add a program header. The PHDRS clause is syntactically distinct |
| 3073 | // from the SECTIONS clause, but we implement it with the SECTIONS |
| 3074 | // support becauase PHDRS is useless if there is no SECTIONS clause. |
| 3075 | |
| 3076 | void |
| 3077 | Script_sections::add_phdr(const char* name, size_t namelen, unsigned int type, |
| 3078 | bool includes_filehdr, bool includes_phdrs, |
| 3079 | bool is_flags_valid, unsigned int flags, |
| 3080 | Expression* load_address) |
| 3081 | { |
| 3082 | if (this->phdrs_elements_ == NULL) |
| 3083 | this->phdrs_elements_ = new Phdrs_elements(); |
| 3084 | this->phdrs_elements_->push_back(new Phdrs_element(name, namelen, type, |
| 3085 | includes_filehdr, |
| 3086 | includes_phdrs, |
| 3087 | is_flags_valid, flags, |
| 3088 | load_address)); |
| 3089 | } |
| 3090 | |
| 3091 | // Return the number of segments we expect to create based on the |
| 3092 | // SECTIONS clause. This is used to implement SIZEOF_HEADERS. |
| 3093 | |
| 3094 | size_t |
| 3095 | Script_sections::expected_segment_count(const Layout* layout) const |
| 3096 | { |
| 3097 | if (this->saw_phdrs_clause()) |
| 3098 | return this->phdrs_elements_->size(); |
| 3099 | |
| 3100 | Layout::Section_list sections; |
| 3101 | layout->get_allocated_sections(§ions); |
| 3102 | |
| 3103 | // We assume that we will need two PT_LOAD segments. |
| 3104 | size_t ret = 2; |
| 3105 | |
| 3106 | bool saw_note = false; |
| 3107 | bool saw_tls = false; |
| 3108 | for (Layout::Section_list::const_iterator p = sections.begin(); |
| 3109 | p != sections.end(); |
| 3110 | ++p) |
| 3111 | { |
| 3112 | if ((*p)->type() == elfcpp::SHT_NOTE) |
| 3113 | { |
| 3114 | // Assume that all note sections will fit into a single |
| 3115 | // PT_NOTE segment. |
| 3116 | if (!saw_note) |
| 3117 | { |
| 3118 | ++ret; |
| 3119 | saw_note = true; |
| 3120 | } |
| 3121 | } |
| 3122 | else if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| 3123 | { |
| 3124 | // There can only be one PT_TLS segment. |
| 3125 | if (!saw_tls) |
| 3126 | { |
| 3127 | ++ret; |
| 3128 | saw_tls = true; |
| 3129 | } |
| 3130 | } |
| 3131 | } |
| 3132 | |
| 3133 | return ret; |
| 3134 | } |
| 3135 | |
| 3136 | // Create the segments from a PHDRS clause. Return the segment which |
| 3137 | // should hold the file header and program headers, if any. |
| 3138 | |
| 3139 | Output_segment* |
| 3140 | Script_sections::create_segments_from_phdrs_clause(Layout* layout) |
| 3141 | { |
| 3142 | this->attach_sections_using_phdrs_clause(layout); |
| 3143 | return this->set_phdrs_clause_addresses(layout); |
| 3144 | } |
| 3145 | |
| 3146 | // Create the segments from the PHDRS clause, and put the output |
| 3147 | // sections in them. |
| 3148 | |
| 3149 | void |
| 3150 | Script_sections::attach_sections_using_phdrs_clause(Layout* layout) |
| 3151 | { |
| 3152 | typedef std::map<std::string, Output_segment*> Name_to_segment; |
| 3153 | Name_to_segment name_to_segment; |
| 3154 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 3155 | p != this->phdrs_elements_->end(); |
| 3156 | ++p) |
| 3157 | name_to_segment[(*p)->name()] = (*p)->create_segment(layout); |
| 3158 | |
| 3159 | // Walk through the output sections and attach them to segments. |
| 3160 | // Output sections in the script which do not list segments are |
| 3161 | // attached to the same set of segments as the immediately preceding |
| 3162 | // output section. |
| 3163 | String_list* phdr_names = NULL; |
| 3164 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3165 | p != this->sections_elements_->end(); |
| 3166 | ++p) |
| 3167 | { |
| 3168 | bool orphan; |
| 3169 | Output_section* os = (*p)->allocate_to_segment(&phdr_names, &orphan); |
| 3170 | if (os == NULL) |
| 3171 | continue; |
| 3172 | |
| 3173 | if (phdr_names == NULL) |
| 3174 | { |
| 3175 | gold_error(_("allocated section not in any segment")); |
| 3176 | continue; |
| 3177 | } |
| 3178 | |
| 3179 | // If this is an orphan section--one that was not explicitly |
| 3180 | // mentioned in the linker script--then it should not inherit |
| 3181 | // any segment type other than PT_LOAD. Otherwise, e.g., the |
| 3182 | // PT_INTERP segment will pick up following orphan sections, |
| 3183 | // which does not make sense. If this is not an orphan section, |
| 3184 | // we trust the linker script. |
| 3185 | if (orphan) |
| 3186 | { |
| 3187 | String_list::iterator q = phdr_names->begin(); |
| 3188 | while (q != phdr_names->end()) |
| 3189 | { |
| 3190 | Name_to_segment::const_iterator r = name_to_segment.find(*q); |
| 3191 | // We give errors about unknown segments below. |
| 3192 | if (r == name_to_segment.end() |
| 3193 | || r->second->type() == elfcpp::PT_LOAD) |
| 3194 | ++q; |
| 3195 | else |
| 3196 | q = phdr_names->erase(q); |
| 3197 | } |
| 3198 | } |
| 3199 | |
| 3200 | bool in_load_segment = false; |
| 3201 | for (String_list::const_iterator q = phdr_names->begin(); |
| 3202 | q != phdr_names->end(); |
| 3203 | ++q) |
| 3204 | { |
| 3205 | Name_to_segment::const_iterator r = name_to_segment.find(*q); |
| 3206 | if (r == name_to_segment.end()) |
| 3207 | gold_error(_("no segment %s"), q->c_str()); |
| 3208 | else |
| 3209 | { |
| 3210 | elfcpp::Elf_Word seg_flags = |
| 3211 | Layout::section_flags_to_segment(os->flags()); |
| 3212 | r->second->add_output_section(os, seg_flags); |
| 3213 | |
| 3214 | if (r->second->type() == elfcpp::PT_LOAD) |
| 3215 | { |
| 3216 | if (in_load_segment) |
| 3217 | gold_error(_("section in two PT_LOAD segments")); |
| 3218 | in_load_segment = true; |
| 3219 | } |
| 3220 | } |
| 3221 | } |
| 3222 | |
| 3223 | if (!in_load_segment) |
| 3224 | gold_error(_("allocated section not in any PT_LOAD segment")); |
| 3225 | } |
| 3226 | } |
| 3227 | |
| 3228 | // Set the addresses for segments created from a PHDRS clause. Return |
| 3229 | // the segment which should hold the file header and program headers, |
| 3230 | // if any. |
| 3231 | |
| 3232 | Output_segment* |
| 3233 | Script_sections::set_phdrs_clause_addresses(Layout* layout) |
| 3234 | { |
| 3235 | Output_segment* load_seg = NULL; |
| 3236 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 3237 | p != this->phdrs_elements_->end(); |
| 3238 | ++p) |
| 3239 | { |
| 3240 | // Note that we have to set the flags after adding the output |
| 3241 | // sections to the segment, as adding an output segment can |
| 3242 | // change the flags. |
| 3243 | (*p)->set_flags_if_valid(); |
| 3244 | |
| 3245 | Output_segment* oseg = (*p)->segment(); |
| 3246 | |
| 3247 | if (oseg->type() != elfcpp::PT_LOAD) |
| 3248 | { |
| 3249 | // The addresses of non-PT_LOAD segments are set from the |
| 3250 | // PT_LOAD segments. |
| 3251 | if ((*p)->has_load_address()) |
| 3252 | gold_error(_("may only specify load address for PT_LOAD segment")); |
| 3253 | continue; |
| 3254 | } |
| 3255 | |
| 3256 | // The output sections should have addresses from the SECTIONS |
| 3257 | // clause. The addresses don't have to be in order, so find the |
| 3258 | // one with the lowest load address. Use that to set the |
| 3259 | // address of the segment. |
| 3260 | |
| 3261 | Output_section* osec = oseg->section_with_lowest_load_address(); |
| 3262 | if (osec == NULL) |
| 3263 | { |
| 3264 | oseg->set_addresses(0, 0); |
| 3265 | continue; |
| 3266 | } |
| 3267 | |
| 3268 | uint64_t vma = osec->address(); |
| 3269 | uint64_t lma = osec->has_load_address() ? osec->load_address() : vma; |
| 3270 | |
| 3271 | // Override the load address of the section with the load |
| 3272 | // address specified for the segment. |
| 3273 | if ((*p)->has_load_address()) |
| 3274 | { |
| 3275 | if (osec->has_load_address()) |
| 3276 | gold_warning(_("PHDRS load address overrides " |
| 3277 | "section %s load address"), |
| 3278 | osec->name()); |
| 3279 | |
| 3280 | lma = (*p)->load_address(); |
| 3281 | } |
| 3282 | |
| 3283 | bool headers = (*p)->includes_filehdr() && (*p)->includes_phdrs(); |
| 3284 | if (!headers && ((*p)->includes_filehdr() || (*p)->includes_phdrs())) |
| 3285 | { |
| 3286 | // We could support this if we wanted to. |
| 3287 | gold_error(_("using only one of FILEHDR and PHDRS is " |
| 3288 | "not currently supported")); |
| 3289 | } |
| 3290 | if (headers) |
| 3291 | { |
| 3292 | size_t sizeof_headers = this->total_header_size(layout); |
| 3293 | uint64_t subtract = this->header_size_adjustment(lma, |
| 3294 | sizeof_headers); |
| 3295 | if (lma >= subtract && vma >= subtract) |
| 3296 | { |
| 3297 | lma -= subtract; |
| 3298 | vma -= subtract; |
| 3299 | } |
| 3300 | else |
| 3301 | { |
| 3302 | gold_error(_("sections loaded on first page without room " |
| 3303 | "for file and program headers " |
| 3304 | "are not supported")); |
| 3305 | } |
| 3306 | |
| 3307 | if (load_seg != NULL) |
| 3308 | gold_error(_("using FILEHDR and PHDRS on more than one " |
| 3309 | "PT_LOAD segment is not currently supported")); |
| 3310 | load_seg = oseg; |
| 3311 | } |
| 3312 | |
| 3313 | oseg->set_addresses(vma, lma); |
| 3314 | } |
| 3315 | |
| 3316 | return load_seg; |
| 3317 | } |
| 3318 | |
| 3319 | // Add the file header and segment headers to non-load segments |
| 3320 | // specified in the PHDRS clause. |
| 3321 | |
| 3322 | void |
| 3323 | Script_sections::put_headers_in_phdrs(Output_data* file_header, |
| 3324 | Output_data* segment_headers) |
| 3325 | { |
| 3326 | gold_assert(this->saw_phdrs_clause()); |
| 3327 | for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| 3328 | p != this->phdrs_elements_->end(); |
| 3329 | ++p) |
| 3330 | { |
| 3331 | if ((*p)->type() != elfcpp::PT_LOAD) |
| 3332 | { |
| 3333 | if ((*p)->includes_phdrs()) |
| 3334 | (*p)->segment()->add_initial_output_data(segment_headers); |
| 3335 | if ((*p)->includes_filehdr()) |
| 3336 | (*p)->segment()->add_initial_output_data(file_header); |
| 3337 | } |
| 3338 | } |
| 3339 | } |
| 3340 | |
| 3341 | // Look for an output section by name and return the address, the load |
| 3342 | // address, the alignment, and the size. This is used when an |
| 3343 | // expression refers to an output section which was not actually |
| 3344 | // created. This returns true if the section was found, false |
| 3345 | // otherwise. |
| 3346 | |
| 3347 | bool |
| 3348 | Script_sections::get_output_section_info(const char* name, uint64_t* address, |
| 3349 | uint64_t* load_address, |
| 3350 | uint64_t* addralign, |
| 3351 | uint64_t* size) const |
| 3352 | { |
| 3353 | if (!this->saw_sections_clause_) |
| 3354 | return false; |
| 3355 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3356 | p != this->sections_elements_->end(); |
| 3357 | ++p) |
| 3358 | if ((*p)->get_output_section_info(name, address, load_address, addralign, |
| 3359 | size)) |
| 3360 | return true; |
| 3361 | return false; |
| 3362 | } |
| 3363 | |
| 3364 | // Print the SECTIONS clause to F for debugging. |
| 3365 | |
| 3366 | void |
| 3367 | Script_sections::print(FILE* f) const |
| 3368 | { |
| 3369 | if (!this->saw_sections_clause_) |
| 3370 | return; |
| 3371 | |
| 3372 | fprintf(f, "SECTIONS {\n"); |
| 3373 | |
| 3374 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3375 | p != this->sections_elements_->end(); |
| 3376 | ++p) |
| 3377 | (*p)->print(f); |
| 3378 | |
| 3379 | fprintf(f, "}\n"); |
| 3380 | |
| 3381 | if (this->phdrs_elements_ != NULL) |
| 3382 | { |
| 3383 | fprintf(f, "PHDRS {\n"); |
| 3384 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 3385 | p != this->phdrs_elements_->end(); |
| 3386 | ++p) |
| 3387 | (*p)->print(f); |
| 3388 | fprintf(f, "}\n"); |
| 3389 | } |
| 3390 | } |
| 3391 | |
| 3392 | } // End namespace gold. |