| 1 | // script-sections.cc -- linker script SECTIONS for gold |
| 2 | |
| 3 | // Copyright (C) 2008-2019 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 | // A region of memory. |
| 47 | class Memory_region |
| 48 | { |
| 49 | public: |
| 50 | Memory_region(const char* name, size_t namelen, unsigned int attributes, |
| 51 | Expression* start, Expression* length) |
| 52 | : name_(name, namelen), |
| 53 | attributes_(attributes), |
| 54 | start_(start), |
| 55 | length_(length), |
| 56 | current_offset_(0), |
| 57 | vma_sections_(), |
| 58 | lma_sections_(), |
| 59 | last_section_(NULL) |
| 60 | { } |
| 61 | |
| 62 | // Return the name of this region. |
| 63 | const std::string& |
| 64 | name() const |
| 65 | { return this->name_; } |
| 66 | |
| 67 | // Return the start address of this region. |
| 68 | Expression* |
| 69 | start_address() const |
| 70 | { return this->start_; } |
| 71 | |
| 72 | // Return the length of this region. |
| 73 | Expression* |
| 74 | length() const |
| 75 | { return this->length_; } |
| 76 | |
| 77 | // Print the region (when debugging). |
| 78 | void |
| 79 | print(FILE*) const; |
| 80 | |
| 81 | // Return true if <name,namelen> matches this region. |
| 82 | bool |
| 83 | name_match(const char* name, size_t namelen) |
| 84 | { |
| 85 | return (this->name_.length() == namelen |
| 86 | && strncmp(this->name_.c_str(), name, namelen) == 0); |
| 87 | } |
| 88 | |
| 89 | Expression* |
| 90 | get_current_address() const |
| 91 | { |
| 92 | return |
| 93 | script_exp_binary_add(this->start_, |
| 94 | script_exp_integer(this->current_offset_)); |
| 95 | } |
| 96 | |
| 97 | void |
| 98 | set_address(uint64_t addr, const Symbol_table* symtab, const Layout* layout) |
| 99 | { |
| 100 | uint64_t start = this->start_->eval(symtab, layout, false); |
| 101 | uint64_t len = this->length_->eval(symtab, layout, false); |
| 102 | if (addr < start || addr >= start + len) |
| 103 | gold_error(_("address 0x%llx is not within region %s"), |
| 104 | static_cast<unsigned long long>(addr), |
| 105 | this->name_.c_str()); |
| 106 | else if (addr < start + this->current_offset_) |
| 107 | gold_error(_("address 0x%llx moves dot backwards in region %s"), |
| 108 | static_cast<unsigned long long>(addr), |
| 109 | this->name_.c_str()); |
| 110 | this->current_offset_ = addr - start; |
| 111 | } |
| 112 | |
| 113 | void |
| 114 | increment_offset(std::string section_name, uint64_t amount, |
| 115 | const Symbol_table* symtab, const Layout* layout) |
| 116 | { |
| 117 | this->current_offset_ += amount; |
| 118 | |
| 119 | if (this->current_offset_ |
| 120 | > this->length_->eval(symtab, layout, false)) |
| 121 | gold_error(_("section %s overflows end of region %s"), |
| 122 | section_name.c_str(), this->name_.c_str()); |
| 123 | } |
| 124 | |
| 125 | // Returns true iff there is room left in this region |
| 126 | // for AMOUNT more bytes of data. |
| 127 | bool |
| 128 | has_room_for(const Symbol_table* symtab, const Layout* layout, |
| 129 | uint64_t amount) const |
| 130 | { |
| 131 | return (this->current_offset_ + amount |
| 132 | < this->length_->eval(symtab, layout, false)); |
| 133 | } |
| 134 | |
| 135 | // Return true if the provided section flags |
| 136 | // are compatible with this region's attributes. |
| 137 | bool |
| 138 | attributes_compatible(elfcpp::Elf_Xword flags, elfcpp::Elf_Xword type) const; |
| 139 | |
| 140 | void |
| 141 | add_section(Output_section_definition* sec, bool vma) |
| 142 | { |
| 143 | if (vma) |
| 144 | this->vma_sections_.push_back(sec); |
| 145 | else |
| 146 | this->lma_sections_.push_back(sec); |
| 147 | } |
| 148 | |
| 149 | typedef std::vector<Output_section_definition*> Section_list; |
| 150 | |
| 151 | // Return the start of the list of sections |
| 152 | // whose VMAs are taken from this region. |
| 153 | Section_list::const_iterator |
| 154 | get_vma_section_list_start() const |
| 155 | { return this->vma_sections_.begin(); } |
| 156 | |
| 157 | // Return the start of the list of sections |
| 158 | // whose LMAs are taken from this region. |
| 159 | Section_list::const_iterator |
| 160 | get_lma_section_list_start() const |
| 161 | { return this->lma_sections_.begin(); } |
| 162 | |
| 163 | // Return the end of the list of sections |
| 164 | // whose VMAs are taken from this region. |
| 165 | Section_list::const_iterator |
| 166 | get_vma_section_list_end() const |
| 167 | { return this->vma_sections_.end(); } |
| 168 | |
| 169 | // Return the end of the list of sections |
| 170 | // whose LMAs are taken from this region. |
| 171 | Section_list::const_iterator |
| 172 | get_lma_section_list_end() const |
| 173 | { return this->lma_sections_.end(); } |
| 174 | |
| 175 | Output_section_definition* |
| 176 | get_last_section() const |
| 177 | { return this->last_section_; } |
| 178 | |
| 179 | void |
| 180 | set_last_section(Output_section_definition* sec) |
| 181 | { this->last_section_ = sec; } |
| 182 | |
| 183 | private: |
| 184 | |
| 185 | std::string name_; |
| 186 | unsigned int attributes_; |
| 187 | Expression* start_; |
| 188 | Expression* length_; |
| 189 | // The offset to the next free byte in the region. |
| 190 | // Note - for compatibility with GNU LD we only maintain one offset |
| 191 | // regardless of whether the region is being used for VMA values, |
| 192 | // LMA values, or both. |
| 193 | uint64_t current_offset_; |
| 194 | // A list of sections whose VMAs are set inside this region. |
| 195 | Section_list vma_sections_; |
| 196 | // A list of sections whose LMAs are set inside this region. |
| 197 | Section_list lma_sections_; |
| 198 | // The latest section to make use of this region. |
| 199 | Output_section_definition* last_section_; |
| 200 | }; |
| 201 | |
| 202 | // Return true if the provided section flags |
| 203 | // are compatible with this region's attributes. |
| 204 | |
| 205 | bool |
| 206 | Memory_region::attributes_compatible(elfcpp::Elf_Xword flags, |
| 207 | elfcpp::Elf_Xword type) const |
| 208 | { |
| 209 | unsigned int attrs = this->attributes_; |
| 210 | |
| 211 | // No attributes means that this region is not compatible with anything. |
| 212 | if (attrs == 0) |
| 213 | return false; |
| 214 | |
| 215 | bool match = true; |
| 216 | do |
| 217 | { |
| 218 | switch (attrs & - attrs) |
| 219 | { |
| 220 | case MEM_EXECUTABLE: |
| 221 | if ((flags & elfcpp::SHF_EXECINSTR) == 0) |
| 222 | match = false; |
| 223 | break; |
| 224 | |
| 225 | case MEM_WRITEABLE: |
| 226 | if ((flags & elfcpp::SHF_WRITE) == 0) |
| 227 | match = false; |
| 228 | break; |
| 229 | |
| 230 | case MEM_READABLE: |
| 231 | // All sections are presumed readable. |
| 232 | break; |
| 233 | |
| 234 | case MEM_ALLOCATABLE: |
| 235 | if ((flags & elfcpp::SHF_ALLOC) == 0) |
| 236 | match = false; |
| 237 | break; |
| 238 | |
| 239 | case MEM_INITIALIZED: |
| 240 | if ((type & elfcpp::SHT_NOBITS) != 0) |
| 241 | match = false; |
| 242 | break; |
| 243 | } |
| 244 | attrs &= ~ (attrs & - attrs); |
| 245 | } |
| 246 | while (attrs != 0); |
| 247 | |
| 248 | return match; |
| 249 | } |
| 250 | |
| 251 | // Print a memory region. |
| 252 | |
| 253 | void |
| 254 | Memory_region::print(FILE* f) const |
| 255 | { |
| 256 | fprintf(f, " %s", this->name_.c_str()); |
| 257 | |
| 258 | unsigned int attrs = this->attributes_; |
| 259 | if (attrs != 0) |
| 260 | { |
| 261 | fprintf(f, " ("); |
| 262 | do |
| 263 | { |
| 264 | switch (attrs & - attrs) |
| 265 | { |
| 266 | case MEM_EXECUTABLE: fputc('x', f); break; |
| 267 | case MEM_WRITEABLE: fputc('w', f); break; |
| 268 | case MEM_READABLE: fputc('r', f); break; |
| 269 | case MEM_ALLOCATABLE: fputc('a', f); break; |
| 270 | case MEM_INITIALIZED: fputc('i', f); break; |
| 271 | default: |
| 272 | gold_unreachable(); |
| 273 | } |
| 274 | attrs &= ~ (attrs & - attrs); |
| 275 | } |
| 276 | while (attrs != 0); |
| 277 | fputc(')', f); |
| 278 | } |
| 279 | |
| 280 | fprintf(f, " : origin = "); |
| 281 | this->start_->print(f); |
| 282 | fprintf(f, ", length = "); |
| 283 | this->length_->print(f); |
| 284 | fprintf(f, "\n"); |
| 285 | } |
| 286 | |
| 287 | // Manage orphan sections. This is intended to be largely compatible |
| 288 | // with the GNU linker. The Linux kernel implicitly relies on |
| 289 | // something similar to the GNU linker's orphan placement. We |
| 290 | // originally used a simpler scheme here, but it caused the kernel |
| 291 | // build to fail, and was also rather inefficient. |
| 292 | |
| 293 | class Orphan_section_placement |
| 294 | { |
| 295 | private: |
| 296 | typedef Script_sections::Elements_iterator Elements_iterator; |
| 297 | |
| 298 | public: |
| 299 | Orphan_section_placement(); |
| 300 | |
| 301 | // Handle an output section during initialization of this mapping. |
| 302 | void |
| 303 | output_section_init(const std::string& name, Output_section*, |
| 304 | Elements_iterator location); |
| 305 | |
| 306 | // Initialize the last location. |
| 307 | void |
| 308 | last_init(Elements_iterator location); |
| 309 | |
| 310 | // Set *PWHERE to the address of an iterator pointing to the |
| 311 | // location to use for an orphan section. Return true if the |
| 312 | // iterator has a value, false otherwise. |
| 313 | bool |
| 314 | find_place(Output_section*, Elements_iterator** pwhere); |
| 315 | |
| 316 | // Update PLACE_LAST_ALLOC. |
| 317 | void |
| 318 | update_last_alloc(Elements_iterator where); |
| 319 | |
| 320 | // Return the iterator being used for sections at the very end of |
| 321 | // the linker script. |
| 322 | Elements_iterator |
| 323 | last_place() const; |
| 324 | |
| 325 | private: |
| 326 | // The places that we specifically recognize. This list is copied |
| 327 | // from the GNU linker. |
| 328 | enum Place_index |
| 329 | { |
| 330 | PLACE_TEXT, |
| 331 | PLACE_RODATA, |
| 332 | PLACE_DATA, |
| 333 | PLACE_TLS, |
| 334 | PLACE_TLS_BSS, |
| 335 | PLACE_BSS, |
| 336 | PLACE_LAST_ALLOC, |
| 337 | PLACE_REL, |
| 338 | PLACE_INTERP, |
| 339 | PLACE_NONALLOC, |
| 340 | PLACE_LAST, |
| 341 | PLACE_MAX |
| 342 | }; |
| 343 | |
| 344 | // The information we keep for a specific place. |
| 345 | struct Place |
| 346 | { |
| 347 | // The name of sections for this place. |
| 348 | const char* name; |
| 349 | // Whether we have a location for this place. |
| 350 | bool have_location; |
| 351 | // The iterator for this place. |
| 352 | Elements_iterator location; |
| 353 | }; |
| 354 | |
| 355 | // Initialize one place element. |
| 356 | void |
| 357 | initialize_place(Place_index, const char*); |
| 358 | |
| 359 | // The places. |
| 360 | Place places_[PLACE_MAX]; |
| 361 | // True if this is the first call to output_section_init. |
| 362 | bool first_init_; |
| 363 | }; |
| 364 | |
| 365 | // Initialize Orphan_section_placement. |
| 366 | |
| 367 | Orphan_section_placement::Orphan_section_placement() |
| 368 | : first_init_(true) |
| 369 | { |
| 370 | this->initialize_place(PLACE_TEXT, ".text"); |
| 371 | this->initialize_place(PLACE_RODATA, ".rodata"); |
| 372 | this->initialize_place(PLACE_DATA, ".data"); |
| 373 | this->initialize_place(PLACE_TLS, NULL); |
| 374 | this->initialize_place(PLACE_TLS_BSS, NULL); |
| 375 | this->initialize_place(PLACE_BSS, ".bss"); |
| 376 | this->initialize_place(PLACE_LAST_ALLOC, NULL); |
| 377 | this->initialize_place(PLACE_REL, NULL); |
| 378 | this->initialize_place(PLACE_INTERP, ".interp"); |
| 379 | this->initialize_place(PLACE_NONALLOC, NULL); |
| 380 | this->initialize_place(PLACE_LAST, NULL); |
| 381 | } |
| 382 | |
| 383 | // Initialize one place element. |
| 384 | |
| 385 | void |
| 386 | Orphan_section_placement::initialize_place(Place_index index, const char* name) |
| 387 | { |
| 388 | this->places_[index].name = name; |
| 389 | this->places_[index].have_location = false; |
| 390 | } |
| 391 | |
| 392 | // While initializing the Orphan_section_placement information, this |
| 393 | // is called once for each output section named in the linker script. |
| 394 | // If we found an output section during the link, it will be passed in |
| 395 | // OS. |
| 396 | |
| 397 | void |
| 398 | Orphan_section_placement::output_section_init(const std::string& name, |
| 399 | Output_section* os, |
| 400 | Elements_iterator location) |
| 401 | { |
| 402 | bool first_init = this->first_init_; |
| 403 | this->first_init_ = false; |
| 404 | |
| 405 | // Remember the last allocated section. Any orphan bss sections |
| 406 | // will be placed after it. |
| 407 | if (os != NULL |
| 408 | && (os->flags() & elfcpp::SHF_ALLOC) != 0) |
| 409 | { |
| 410 | this->places_[PLACE_LAST_ALLOC].location = location; |
| 411 | this->places_[PLACE_LAST_ALLOC].have_location = true; |
| 412 | } |
| 413 | |
| 414 | for (int i = 0; i < PLACE_MAX; ++i) |
| 415 | { |
| 416 | if (this->places_[i].name != NULL && this->places_[i].name == name) |
| 417 | { |
| 418 | if (this->places_[i].have_location) |
| 419 | { |
| 420 | // We have already seen a section with this name. |
| 421 | return; |
| 422 | } |
| 423 | |
| 424 | this->places_[i].location = location; |
| 425 | this->places_[i].have_location = true; |
| 426 | |
| 427 | // If we just found the .bss section, restart the search for |
| 428 | // an unallocated section. This follows the GNU linker's |
| 429 | // behaviour. |
| 430 | if (i == PLACE_BSS) |
| 431 | this->places_[PLACE_NONALLOC].have_location = false; |
| 432 | |
| 433 | return; |
| 434 | } |
| 435 | } |
| 436 | |
| 437 | // Relocation sections. |
| 438 | if (!this->places_[PLACE_REL].have_location |
| 439 | && os != NULL |
| 440 | && (os->type() == elfcpp::SHT_REL || os->type() == elfcpp::SHT_RELA) |
| 441 | && (os->flags() & elfcpp::SHF_ALLOC) != 0) |
| 442 | { |
| 443 | this->places_[PLACE_REL].location = location; |
| 444 | this->places_[PLACE_REL].have_location = true; |
| 445 | } |
| 446 | |
| 447 | // We find the location for unallocated sections by finding the |
| 448 | // first debugging or comment section after the BSS section (if |
| 449 | // there is one). |
| 450 | if (!this->places_[PLACE_NONALLOC].have_location |
| 451 | && (name == ".comment" || Layout::is_debug_info_section(name.c_str()))) |
| 452 | { |
| 453 | // We add orphan sections after the location in PLACES_. We |
| 454 | // want to store unallocated sections before LOCATION. If this |
| 455 | // is the very first section, we can't use it. |
| 456 | if (!first_init) |
| 457 | { |
| 458 | --location; |
| 459 | this->places_[PLACE_NONALLOC].location = location; |
| 460 | this->places_[PLACE_NONALLOC].have_location = true; |
| 461 | } |
| 462 | } |
| 463 | } |
| 464 | |
| 465 | // Initialize the last location. |
| 466 | |
| 467 | void |
| 468 | Orphan_section_placement::last_init(Elements_iterator location) |
| 469 | { |
| 470 | this->places_[PLACE_LAST].location = location; |
| 471 | this->places_[PLACE_LAST].have_location = true; |
| 472 | } |
| 473 | |
| 474 | // Set *PWHERE to the address of an iterator pointing to the location |
| 475 | // to use for an orphan section. Return true if the iterator has a |
| 476 | // value, false otherwise. |
| 477 | |
| 478 | bool |
| 479 | Orphan_section_placement::find_place(Output_section* os, |
| 480 | Elements_iterator** pwhere) |
| 481 | { |
| 482 | // Figure out where OS should go. This is based on the GNU linker |
| 483 | // code. FIXME: The GNU linker handles small data sections |
| 484 | // specially, but we don't. |
| 485 | elfcpp::Elf_Word type = os->type(); |
| 486 | elfcpp::Elf_Xword flags = os->flags(); |
| 487 | Place_index index; |
| 488 | if ((flags & elfcpp::SHF_ALLOC) == 0 |
| 489 | && !Layout::is_debug_info_section(os->name())) |
| 490 | index = PLACE_NONALLOC; |
| 491 | else if ((flags & elfcpp::SHF_ALLOC) == 0) |
| 492 | index = PLACE_LAST; |
| 493 | else if (type == elfcpp::SHT_NOTE) |
| 494 | index = PLACE_INTERP; |
| 495 | else if ((flags & elfcpp::SHF_TLS) != 0) |
| 496 | { |
| 497 | if (type == elfcpp::SHT_NOBITS) |
| 498 | index = PLACE_TLS_BSS; |
| 499 | else |
| 500 | index = PLACE_TLS; |
| 501 | } |
| 502 | else if (type == elfcpp::SHT_NOBITS) |
| 503 | index = PLACE_BSS; |
| 504 | else if ((flags & elfcpp::SHF_WRITE) != 0) |
| 505 | index = PLACE_DATA; |
| 506 | else if (type == elfcpp::SHT_REL || type == elfcpp::SHT_RELA) |
| 507 | index = PLACE_REL; |
| 508 | else if ((flags & elfcpp::SHF_EXECINSTR) == 0) |
| 509 | index = PLACE_RODATA; |
| 510 | else |
| 511 | index = PLACE_TEXT; |
| 512 | |
| 513 | // If we don't have a location yet, try to find one based on a |
| 514 | // plausible ordering of sections. |
| 515 | if (!this->places_[index].have_location) |
| 516 | { |
| 517 | Place_index follow; |
| 518 | switch (index) |
| 519 | { |
| 520 | default: |
| 521 | follow = PLACE_MAX; |
| 522 | break; |
| 523 | case PLACE_RODATA: |
| 524 | follow = PLACE_TEXT; |
| 525 | break; |
| 526 | case PLACE_DATA: |
| 527 | follow = PLACE_RODATA; |
| 528 | if (!this->places_[PLACE_RODATA].have_location) |
| 529 | follow = PLACE_TEXT; |
| 530 | break; |
| 531 | case PLACE_BSS: |
| 532 | follow = PLACE_LAST_ALLOC; |
| 533 | break; |
| 534 | case PLACE_REL: |
| 535 | follow = PLACE_TEXT; |
| 536 | break; |
| 537 | case PLACE_INTERP: |
| 538 | follow = PLACE_TEXT; |
| 539 | break; |
| 540 | case PLACE_TLS: |
| 541 | follow = PLACE_DATA; |
| 542 | break; |
| 543 | case PLACE_TLS_BSS: |
| 544 | follow = PLACE_TLS; |
| 545 | if (!this->places_[PLACE_TLS].have_location) |
| 546 | follow = PLACE_DATA; |
| 547 | break; |
| 548 | } |
| 549 | if (follow != PLACE_MAX && this->places_[follow].have_location) |
| 550 | { |
| 551 | // Set the location of INDEX to the location of FOLLOW. The |
| 552 | // location of INDEX will then be incremented by the caller, |
| 553 | // so anything in INDEX will continue to be after anything |
| 554 | // in FOLLOW. |
| 555 | this->places_[index].location = this->places_[follow].location; |
| 556 | this->places_[index].have_location = true; |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | *pwhere = &this->places_[index].location; |
| 561 | bool ret = this->places_[index].have_location; |
| 562 | |
| 563 | // The caller will set the location. |
| 564 | this->places_[index].have_location = true; |
| 565 | |
| 566 | return ret; |
| 567 | } |
| 568 | |
| 569 | // Update PLACE_LAST_ALLOC. |
| 570 | void |
| 571 | Orphan_section_placement::update_last_alloc(Elements_iterator elem) |
| 572 | { |
| 573 | Elements_iterator prev = elem; |
| 574 | --prev; |
| 575 | if (this->places_[PLACE_LAST_ALLOC].have_location |
| 576 | && this->places_[PLACE_LAST_ALLOC].location == prev) |
| 577 | { |
| 578 | this->places_[PLACE_LAST_ALLOC].have_location = true; |
| 579 | this->places_[PLACE_LAST_ALLOC].location = elem; |
| 580 | } |
| 581 | } |
| 582 | |
| 583 | // Return the iterator being used for sections at the very end of the |
| 584 | // linker script. |
| 585 | |
| 586 | Orphan_section_placement::Elements_iterator |
| 587 | Orphan_section_placement::last_place() const |
| 588 | { |
| 589 | gold_assert(this->places_[PLACE_LAST].have_location); |
| 590 | return this->places_[PLACE_LAST].location; |
| 591 | } |
| 592 | |
| 593 | // An element in a SECTIONS clause. |
| 594 | |
| 595 | class Sections_element |
| 596 | { |
| 597 | public: |
| 598 | Sections_element() |
| 599 | { } |
| 600 | |
| 601 | virtual ~Sections_element() |
| 602 | { } |
| 603 | |
| 604 | // Return whether an output section is relro. |
| 605 | virtual bool |
| 606 | is_relro() const |
| 607 | { return false; } |
| 608 | |
| 609 | // Record that an output section is relro. |
| 610 | virtual void |
| 611 | set_is_relro() |
| 612 | { } |
| 613 | |
| 614 | // Create any required output sections. The only real |
| 615 | // implementation is in Output_section_definition. |
| 616 | virtual void |
| 617 | create_sections(Layout*) |
| 618 | { } |
| 619 | |
| 620 | // Add any symbol being defined to the symbol table. |
| 621 | virtual void |
| 622 | add_symbols_to_table(Symbol_table*) |
| 623 | { } |
| 624 | |
| 625 | // Finalize symbols and check assertions. |
| 626 | virtual void |
| 627 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*) |
| 628 | { } |
| 629 | |
| 630 | // Return the output section name to use for an input file name and |
| 631 | // section name. This only real implementation is in |
| 632 | // Output_section_definition. |
| 633 | virtual const char* |
| 634 | output_section_name(const char*, const char*, Output_section***, |
| 635 | Script_sections::Section_type*, bool*, bool) |
| 636 | { return NULL; } |
| 637 | |
| 638 | // Initialize OSP with an output section. |
| 639 | virtual void |
| 640 | orphan_section_init(Orphan_section_placement*, |
| 641 | Script_sections::Elements_iterator) |
| 642 | { } |
| 643 | |
| 644 | // Set section addresses. This includes applying assignments if the |
| 645 | // expression is an absolute value. |
| 646 | virtual void |
| 647 | set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*, |
| 648 | uint64_t*) |
| 649 | { } |
| 650 | |
| 651 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 652 | // this section is constrained, and the input sections do not match, |
| 653 | // return the constraint, and set *POSD. |
| 654 | virtual Section_constraint |
| 655 | check_constraint(Output_section_definition**) |
| 656 | { return CONSTRAINT_NONE; } |
| 657 | |
| 658 | // See if this is the alternate output section for a constrained |
| 659 | // output section. If it is, transfer the Output_section and return |
| 660 | // true. Otherwise return false. |
| 661 | virtual bool |
| 662 | alternate_constraint(Output_section_definition*, Section_constraint) |
| 663 | { return false; } |
| 664 | |
| 665 | // Get the list of segments to use for an allocated section when |
| 666 | // using a PHDRS clause. If this is an allocated section, return |
| 667 | // the Output_section, and set *PHDRS_LIST (the first parameter) to |
| 668 | // the list of PHDRS to which it should be attached. If the PHDRS |
| 669 | // were not specified, don't change *PHDRS_LIST. When not returning |
| 670 | // NULL, set *ORPHAN (the second parameter) according to whether |
| 671 | // this is an orphan section--one that is not mentioned in the |
| 672 | // linker script. |
| 673 | virtual Output_section* |
| 674 | allocate_to_segment(String_list**, bool*) |
| 675 | { return NULL; } |
| 676 | |
| 677 | // Look for an output section by name and return the address, the |
| 678 | // load address, the alignment, and the size. This is used when an |
| 679 | // expression refers to an output section which was not actually |
| 680 | // created. This returns true if the section was found, false |
| 681 | // otherwise. The only real definition is for |
| 682 | // Output_section_definition. |
| 683 | virtual bool |
| 684 | get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| 685 | uint64_t*) const |
| 686 | { return false; } |
| 687 | |
| 688 | // Return the associated Output_section if there is one. |
| 689 | virtual Output_section* |
| 690 | get_output_section() const |
| 691 | { return NULL; } |
| 692 | |
| 693 | // Set the section's memory regions. |
| 694 | virtual void |
| 695 | set_memory_region(Memory_region*, bool) |
| 696 | { gold_error(_("Attempt to set a memory region for a non-output section")); } |
| 697 | |
| 698 | // Print the element for debugging purposes. |
| 699 | virtual void |
| 700 | print(FILE* f) const = 0; |
| 701 | }; |
| 702 | |
| 703 | // An assignment in a SECTIONS clause outside of an output section. |
| 704 | |
| 705 | class Sections_element_assignment : public Sections_element |
| 706 | { |
| 707 | public: |
| 708 | Sections_element_assignment(const char* name, size_t namelen, |
| 709 | Expression* val, bool provide, bool hidden) |
| 710 | : assignment_(name, namelen, false, val, provide, hidden) |
| 711 | { } |
| 712 | |
| 713 | // Add the symbol to the symbol table. |
| 714 | void |
| 715 | add_symbols_to_table(Symbol_table* symtab) |
| 716 | { this->assignment_.add_to_table(symtab); } |
| 717 | |
| 718 | // Finalize the symbol. |
| 719 | void |
| 720 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 721 | uint64_t* dot_value) |
| 722 | { |
| 723 | this->assignment_.finalize_with_dot(symtab, layout, *dot_value, NULL); |
| 724 | } |
| 725 | |
| 726 | // Set the section address. There is no section here, but if the |
| 727 | // value is absolute, we set the symbol. This permits us to use |
| 728 | // absolute symbols when setting dot. |
| 729 | void |
| 730 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 731 | uint64_t* dot_value, uint64_t*, uint64_t*) |
| 732 | { |
| 733 | this->assignment_.set_if_absolute(symtab, layout, true, *dot_value, NULL); |
| 734 | } |
| 735 | |
| 736 | // Print for debugging. |
| 737 | void |
| 738 | print(FILE* f) const |
| 739 | { |
| 740 | fprintf(f, " "); |
| 741 | this->assignment_.print(f); |
| 742 | } |
| 743 | |
| 744 | private: |
| 745 | Symbol_assignment assignment_; |
| 746 | }; |
| 747 | |
| 748 | // An assignment to the dot symbol in a SECTIONS clause outside of an |
| 749 | // output section. |
| 750 | |
| 751 | class Sections_element_dot_assignment : public Sections_element |
| 752 | { |
| 753 | public: |
| 754 | Sections_element_dot_assignment(Expression* val) |
| 755 | : val_(val) |
| 756 | { } |
| 757 | |
| 758 | // Finalize the symbol. |
| 759 | void |
| 760 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 761 | uint64_t* dot_value) |
| 762 | { |
| 763 | // We ignore the section of the result because outside of an |
| 764 | // output section definition the dot symbol is always considered |
| 765 | // to be absolute. |
| 766 | *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| 767 | NULL, NULL, NULL, false); |
| 768 | } |
| 769 | |
| 770 | // Update the dot symbol while setting section addresses. |
| 771 | void |
| 772 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 773 | uint64_t* dot_value, uint64_t* dot_alignment, |
| 774 | uint64_t* load_address) |
| 775 | { |
| 776 | *dot_value = this->val_->eval_with_dot(symtab, layout, false, *dot_value, |
| 777 | NULL, NULL, dot_alignment, false); |
| 778 | *load_address = *dot_value; |
| 779 | } |
| 780 | |
| 781 | // Print for debugging. |
| 782 | void |
| 783 | print(FILE* f) const |
| 784 | { |
| 785 | fprintf(f, " . = "); |
| 786 | this->val_->print(f); |
| 787 | fprintf(f, "\n"); |
| 788 | } |
| 789 | |
| 790 | private: |
| 791 | Expression* val_; |
| 792 | }; |
| 793 | |
| 794 | // An assertion in a SECTIONS clause outside of an output section. |
| 795 | |
| 796 | class Sections_element_assertion : public Sections_element |
| 797 | { |
| 798 | public: |
| 799 | Sections_element_assertion(Expression* check, const char* message, |
| 800 | size_t messagelen) |
| 801 | : assertion_(check, message, messagelen) |
| 802 | { } |
| 803 | |
| 804 | // Check the assertion. |
| 805 | void |
| 806 | finalize_symbols(Symbol_table* symtab, const Layout* layout, uint64_t*) |
| 807 | { this->assertion_.check(symtab, layout); } |
| 808 | |
| 809 | // Print for debugging. |
| 810 | void |
| 811 | print(FILE* f) const |
| 812 | { |
| 813 | fprintf(f, " "); |
| 814 | this->assertion_.print(f); |
| 815 | } |
| 816 | |
| 817 | private: |
| 818 | Script_assertion assertion_; |
| 819 | }; |
| 820 | |
| 821 | // An element in an output section in a SECTIONS clause. |
| 822 | |
| 823 | class Output_section_element |
| 824 | { |
| 825 | public: |
| 826 | // A list of input sections. |
| 827 | typedef std::list<Output_section::Input_section> Input_section_list; |
| 828 | |
| 829 | Output_section_element() |
| 830 | { } |
| 831 | |
| 832 | virtual ~Output_section_element() |
| 833 | { } |
| 834 | |
| 835 | // Return whether this element requires an output section to exist. |
| 836 | virtual bool |
| 837 | needs_output_section() const |
| 838 | { return false; } |
| 839 | |
| 840 | // Add any symbol being defined to the symbol table. |
| 841 | virtual void |
| 842 | add_symbols_to_table(Symbol_table*) |
| 843 | { } |
| 844 | |
| 845 | // Finalize symbols and check assertions. |
| 846 | virtual void |
| 847 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*, Output_section**) |
| 848 | { } |
| 849 | |
| 850 | // Return whether this element matches FILE_NAME and SECTION_NAME. |
| 851 | // The only real implementation is in Output_section_element_input. |
| 852 | virtual bool |
| 853 | match_name(const char*, const char*, bool *) const |
| 854 | { return false; } |
| 855 | |
| 856 | // Set section addresses. This includes applying assignments if the |
| 857 | // expression is an absolute value. |
| 858 | virtual void |
| 859 | set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| 860 | uint64_t*, uint64_t*, Output_section**, std::string*, |
| 861 | Input_section_list*) |
| 862 | { } |
| 863 | |
| 864 | // Print the element for debugging purposes. |
| 865 | virtual void |
| 866 | print(FILE* f) const = 0; |
| 867 | |
| 868 | protected: |
| 869 | // Return a fill string that is LENGTH bytes long, filling it with |
| 870 | // FILL. |
| 871 | std::string |
| 872 | get_fill_string(const std::string* fill, section_size_type length) const; |
| 873 | }; |
| 874 | |
| 875 | std::string |
| 876 | Output_section_element::get_fill_string(const std::string* fill, |
| 877 | section_size_type length) const |
| 878 | { |
| 879 | std::string this_fill; |
| 880 | this_fill.reserve(length); |
| 881 | while (this_fill.length() + fill->length() <= length) |
| 882 | this_fill += *fill; |
| 883 | if (this_fill.length() < length) |
| 884 | this_fill.append(*fill, 0, length - this_fill.length()); |
| 885 | return this_fill; |
| 886 | } |
| 887 | |
| 888 | // A symbol assignment in an output section. |
| 889 | |
| 890 | class Output_section_element_assignment : public Output_section_element |
| 891 | { |
| 892 | public: |
| 893 | Output_section_element_assignment(const char* name, size_t namelen, |
| 894 | Expression* val, bool provide, |
| 895 | bool hidden) |
| 896 | : assignment_(name, namelen, false, val, provide, hidden) |
| 897 | { } |
| 898 | |
| 899 | // Add the symbol to the symbol table. |
| 900 | void |
| 901 | add_symbols_to_table(Symbol_table* symtab) |
| 902 | { this->assignment_.add_to_table(symtab); } |
| 903 | |
| 904 | // Finalize the symbol. |
| 905 | void |
| 906 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 907 | uint64_t* dot_value, Output_section** dot_section) |
| 908 | { |
| 909 | this->assignment_.finalize_with_dot(symtab, layout, *dot_value, |
| 910 | *dot_section); |
| 911 | } |
| 912 | |
| 913 | // Set the section address. There is no section here, but if the |
| 914 | // value is absolute, we set the symbol. This permits us to use |
| 915 | // absolute symbols when setting dot. |
| 916 | void |
| 917 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 918 | uint64_t, uint64_t* dot_value, uint64_t*, |
| 919 | Output_section** dot_section, std::string*, |
| 920 | Input_section_list*) |
| 921 | { |
| 922 | this->assignment_.set_if_absolute(symtab, layout, true, *dot_value, |
| 923 | *dot_section); |
| 924 | } |
| 925 | |
| 926 | // Print for debugging. |
| 927 | void |
| 928 | print(FILE* f) const |
| 929 | { |
| 930 | fprintf(f, " "); |
| 931 | this->assignment_.print(f); |
| 932 | } |
| 933 | |
| 934 | private: |
| 935 | Symbol_assignment assignment_; |
| 936 | }; |
| 937 | |
| 938 | // An assignment to the dot symbol in an output section. |
| 939 | |
| 940 | class Output_section_element_dot_assignment : public Output_section_element |
| 941 | { |
| 942 | public: |
| 943 | Output_section_element_dot_assignment(Expression* val) |
| 944 | : val_(val) |
| 945 | { } |
| 946 | |
| 947 | // An assignment to dot within an output section is enough to force |
| 948 | // the output section to exist. |
| 949 | bool |
| 950 | needs_output_section() const |
| 951 | { return true; } |
| 952 | |
| 953 | // Finalize the symbol. |
| 954 | void |
| 955 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 956 | uint64_t* dot_value, Output_section** dot_section) |
| 957 | { |
| 958 | *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| 959 | *dot_section, dot_section, NULL, |
| 960 | true); |
| 961 | } |
| 962 | |
| 963 | // Update the dot symbol while setting section addresses. |
| 964 | void |
| 965 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 966 | uint64_t, uint64_t* dot_value, uint64_t*, |
| 967 | Output_section** dot_section, std::string*, |
| 968 | Input_section_list*); |
| 969 | |
| 970 | // Print for debugging. |
| 971 | void |
| 972 | print(FILE* f) const |
| 973 | { |
| 974 | fprintf(f, " . = "); |
| 975 | this->val_->print(f); |
| 976 | fprintf(f, "\n"); |
| 977 | } |
| 978 | |
| 979 | private: |
| 980 | Expression* val_; |
| 981 | }; |
| 982 | |
| 983 | // Update the dot symbol while setting section addresses. |
| 984 | |
| 985 | void |
| 986 | Output_section_element_dot_assignment::set_section_addresses( |
| 987 | Symbol_table* symtab, |
| 988 | Layout* layout, |
| 989 | Output_section* output_section, |
| 990 | uint64_t, |
| 991 | uint64_t* dot_value, |
| 992 | uint64_t* dot_alignment, |
| 993 | Output_section** dot_section, |
| 994 | std::string* fill, |
| 995 | Input_section_list*) |
| 996 | { |
| 997 | uint64_t next_dot = this->val_->eval_with_dot(symtab, layout, false, |
| 998 | *dot_value, *dot_section, |
| 999 | dot_section, dot_alignment, |
| 1000 | true); |
| 1001 | if (next_dot < *dot_value) |
| 1002 | gold_error(_("dot may not move backward")); |
| 1003 | if (next_dot > *dot_value && output_section != NULL) |
| 1004 | { |
| 1005 | section_size_type length = convert_to_section_size_type(next_dot |
| 1006 | - *dot_value); |
| 1007 | Output_section_data* posd; |
| 1008 | if (fill->empty()) |
| 1009 | posd = new Output_data_zero_fill(length, 0); |
| 1010 | else |
| 1011 | { |
| 1012 | std::string this_fill = this->get_fill_string(fill, length); |
| 1013 | posd = new Output_data_const(this_fill, 0); |
| 1014 | } |
| 1015 | output_section->add_output_section_data(posd); |
| 1016 | layout->new_output_section_data_from_script(posd); |
| 1017 | } |
| 1018 | *dot_value = next_dot; |
| 1019 | } |
| 1020 | |
| 1021 | // An assertion in an output section. |
| 1022 | |
| 1023 | class Output_section_element_assertion : public Output_section_element |
| 1024 | { |
| 1025 | public: |
| 1026 | Output_section_element_assertion(Expression* check, const char* message, |
| 1027 | size_t messagelen) |
| 1028 | : assertion_(check, message, messagelen) |
| 1029 | { } |
| 1030 | |
| 1031 | void |
| 1032 | print(FILE* f) const |
| 1033 | { |
| 1034 | fprintf(f, " "); |
| 1035 | this->assertion_.print(f); |
| 1036 | } |
| 1037 | |
| 1038 | private: |
| 1039 | Script_assertion assertion_; |
| 1040 | }; |
| 1041 | |
| 1042 | // We use a special instance of Output_section_data to handle BYTE, |
| 1043 | // SHORT, etc. This permits forward references to symbols in the |
| 1044 | // expressions. |
| 1045 | |
| 1046 | class Output_data_expression : public Output_section_data |
| 1047 | { |
| 1048 | public: |
| 1049 | Output_data_expression(int size, bool is_signed, Expression* val, |
| 1050 | const Symbol_table* symtab, const Layout* layout, |
| 1051 | uint64_t dot_value, Output_section* dot_section) |
| 1052 | : Output_section_data(size, 0, true), |
| 1053 | is_signed_(is_signed), val_(val), symtab_(symtab), |
| 1054 | layout_(layout), dot_value_(dot_value), dot_section_(dot_section) |
| 1055 | { } |
| 1056 | |
| 1057 | protected: |
| 1058 | // Write the data to the output file. |
| 1059 | void |
| 1060 | do_write(Output_file*); |
| 1061 | |
| 1062 | // Write the data to a buffer. |
| 1063 | void |
| 1064 | do_write_to_buffer(unsigned char*); |
| 1065 | |
| 1066 | // Write to a map file. |
| 1067 | void |
| 1068 | do_print_to_mapfile(Mapfile* mapfile) const |
| 1069 | { mapfile->print_output_data(this, _("** expression")); } |
| 1070 | |
| 1071 | private: |
| 1072 | template<bool big_endian> |
| 1073 | void |
| 1074 | endian_write_to_buffer(uint64_t, unsigned char*); |
| 1075 | |
| 1076 | bool is_signed_; |
| 1077 | Expression* val_; |
| 1078 | const Symbol_table* symtab_; |
| 1079 | const Layout* layout_; |
| 1080 | uint64_t dot_value_; |
| 1081 | Output_section* dot_section_; |
| 1082 | }; |
| 1083 | |
| 1084 | // Write the data element to the output file. |
| 1085 | |
| 1086 | void |
| 1087 | Output_data_expression::do_write(Output_file* of) |
| 1088 | { |
| 1089 | unsigned char* view = of->get_output_view(this->offset(), this->data_size()); |
| 1090 | this->write_to_buffer(view); |
| 1091 | of->write_output_view(this->offset(), this->data_size(), view); |
| 1092 | } |
| 1093 | |
| 1094 | // Write the data element to a buffer. |
| 1095 | |
| 1096 | void |
| 1097 | Output_data_expression::do_write_to_buffer(unsigned char* buf) |
| 1098 | { |
| 1099 | uint64_t val = this->val_->eval_with_dot(this->symtab_, this->layout_, |
| 1100 | true, this->dot_value_, |
| 1101 | this->dot_section_, NULL, NULL, |
| 1102 | false); |
| 1103 | |
| 1104 | if (parameters->target().is_big_endian()) |
| 1105 | this->endian_write_to_buffer<true>(val, buf); |
| 1106 | else |
| 1107 | this->endian_write_to_buffer<false>(val, buf); |
| 1108 | } |
| 1109 | |
| 1110 | template<bool big_endian> |
| 1111 | void |
| 1112 | Output_data_expression::endian_write_to_buffer(uint64_t val, |
| 1113 | unsigned char* buf) |
| 1114 | { |
| 1115 | switch (this->data_size()) |
| 1116 | { |
| 1117 | case 1: |
| 1118 | elfcpp::Swap_unaligned<8, big_endian>::writeval(buf, val); |
| 1119 | break; |
| 1120 | case 2: |
| 1121 | elfcpp::Swap_unaligned<16, big_endian>::writeval(buf, val); |
| 1122 | break; |
| 1123 | case 4: |
| 1124 | elfcpp::Swap_unaligned<32, big_endian>::writeval(buf, val); |
| 1125 | break; |
| 1126 | case 8: |
| 1127 | if (parameters->target().get_size() == 32) |
| 1128 | { |
| 1129 | val &= 0xffffffff; |
| 1130 | if (this->is_signed_ && (val & 0x80000000) != 0) |
| 1131 | val |= 0xffffffff00000000LL; |
| 1132 | } |
| 1133 | elfcpp::Swap_unaligned<64, big_endian>::writeval(buf, val); |
| 1134 | break; |
| 1135 | default: |
| 1136 | gold_unreachable(); |
| 1137 | } |
| 1138 | } |
| 1139 | |
| 1140 | // A data item in an output section. |
| 1141 | |
| 1142 | class Output_section_element_data : public Output_section_element |
| 1143 | { |
| 1144 | public: |
| 1145 | Output_section_element_data(int size, bool is_signed, Expression* val) |
| 1146 | : size_(size), is_signed_(is_signed), val_(val) |
| 1147 | { } |
| 1148 | |
| 1149 | // If there is a data item, then we must create an output section. |
| 1150 | bool |
| 1151 | needs_output_section() const |
| 1152 | { return true; } |
| 1153 | |
| 1154 | // Finalize symbols--we just need to update dot. |
| 1155 | void |
| 1156 | finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| 1157 | Output_section**) |
| 1158 | { *dot_value += this->size_; } |
| 1159 | |
| 1160 | // Store the value in the section. |
| 1161 | void |
| 1162 | set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| 1163 | uint64_t* dot_value, uint64_t*, Output_section**, |
| 1164 | std::string*, Input_section_list*); |
| 1165 | |
| 1166 | // Print for debugging. |
| 1167 | void |
| 1168 | print(FILE*) const; |
| 1169 | |
| 1170 | private: |
| 1171 | // The size in bytes. |
| 1172 | int size_; |
| 1173 | // Whether the value is signed. |
| 1174 | bool is_signed_; |
| 1175 | // The value. |
| 1176 | Expression* val_; |
| 1177 | }; |
| 1178 | |
| 1179 | // Store the value in the section. |
| 1180 | |
| 1181 | void |
| 1182 | Output_section_element_data::set_section_addresses( |
| 1183 | Symbol_table* symtab, |
| 1184 | Layout* layout, |
| 1185 | Output_section* os, |
| 1186 | uint64_t, |
| 1187 | uint64_t* dot_value, |
| 1188 | uint64_t*, |
| 1189 | Output_section** dot_section, |
| 1190 | std::string*, |
| 1191 | Input_section_list*) |
| 1192 | { |
| 1193 | gold_assert(os != NULL); |
| 1194 | Output_data_expression* expression = |
| 1195 | new Output_data_expression(this->size_, this->is_signed_, this->val_, |
| 1196 | symtab, layout, *dot_value, *dot_section); |
| 1197 | os->add_output_section_data(expression); |
| 1198 | layout->new_output_section_data_from_script(expression); |
| 1199 | *dot_value += this->size_; |
| 1200 | } |
| 1201 | |
| 1202 | // Print for debugging. |
| 1203 | |
| 1204 | void |
| 1205 | Output_section_element_data::print(FILE* f) const |
| 1206 | { |
| 1207 | const char* s; |
| 1208 | switch (this->size_) |
| 1209 | { |
| 1210 | case 1: |
| 1211 | s = "BYTE"; |
| 1212 | break; |
| 1213 | case 2: |
| 1214 | s = "SHORT"; |
| 1215 | break; |
| 1216 | case 4: |
| 1217 | s = "LONG"; |
| 1218 | break; |
| 1219 | case 8: |
| 1220 | if (this->is_signed_) |
| 1221 | s = "SQUAD"; |
| 1222 | else |
| 1223 | s = "QUAD"; |
| 1224 | break; |
| 1225 | default: |
| 1226 | gold_unreachable(); |
| 1227 | } |
| 1228 | fprintf(f, " %s(", s); |
| 1229 | this->val_->print(f); |
| 1230 | fprintf(f, ")\n"); |
| 1231 | } |
| 1232 | |
| 1233 | // A fill value setting in an output section. |
| 1234 | |
| 1235 | class Output_section_element_fill : public Output_section_element |
| 1236 | { |
| 1237 | public: |
| 1238 | Output_section_element_fill(Expression* val) |
| 1239 | : val_(val) |
| 1240 | { } |
| 1241 | |
| 1242 | // Update the fill value while setting section addresses. |
| 1243 | void |
| 1244 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 1245 | uint64_t, uint64_t* dot_value, uint64_t*, |
| 1246 | Output_section** dot_section, |
| 1247 | std::string* fill, Input_section_list*) |
| 1248 | { |
| 1249 | Output_section* fill_section; |
| 1250 | uint64_t fill_val = this->val_->eval_with_dot(symtab, layout, false, |
| 1251 | *dot_value, *dot_section, |
| 1252 | &fill_section, NULL, false); |
| 1253 | if (fill_section != NULL) |
| 1254 | gold_warning(_("fill value is not absolute")); |
| 1255 | // FIXME: The GNU linker supports fill values of arbitrary length. |
| 1256 | unsigned char fill_buff[4]; |
| 1257 | elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| 1258 | fill->assign(reinterpret_cast<char*>(fill_buff), 4); |
| 1259 | } |
| 1260 | |
| 1261 | // Print for debugging. |
| 1262 | void |
| 1263 | print(FILE* f) const |
| 1264 | { |
| 1265 | fprintf(f, " FILL("); |
| 1266 | this->val_->print(f); |
| 1267 | fprintf(f, ")\n"); |
| 1268 | } |
| 1269 | |
| 1270 | private: |
| 1271 | // The new fill value. |
| 1272 | Expression* val_; |
| 1273 | }; |
| 1274 | |
| 1275 | // An input section specification in an output section |
| 1276 | |
| 1277 | class Output_section_element_input : public Output_section_element |
| 1278 | { |
| 1279 | public: |
| 1280 | Output_section_element_input(const Input_section_spec* spec, bool keep); |
| 1281 | |
| 1282 | // Finalize symbols--just update the value of the dot symbol. |
| 1283 | void |
| 1284 | finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| 1285 | Output_section** dot_section) |
| 1286 | { |
| 1287 | *dot_value = this->final_dot_value_; |
| 1288 | *dot_section = this->final_dot_section_; |
| 1289 | } |
| 1290 | |
| 1291 | // See whether we match FILE_NAME and SECTION_NAME as an input section. |
| 1292 | // If we do then also indicate whether the section should be KEPT. |
| 1293 | bool |
| 1294 | match_name(const char* file_name, const char* section_name, bool* keep) const; |
| 1295 | |
| 1296 | // Set the section address. |
| 1297 | void |
| 1298 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 1299 | uint64_t subalign, uint64_t* dot_value, uint64_t*, |
| 1300 | Output_section**, std::string* fill, |
| 1301 | Input_section_list*); |
| 1302 | |
| 1303 | // Print for debugging. |
| 1304 | void |
| 1305 | print(FILE* f) const; |
| 1306 | |
| 1307 | private: |
| 1308 | // An input section pattern. |
| 1309 | struct Input_section_pattern |
| 1310 | { |
| 1311 | std::string pattern; |
| 1312 | bool pattern_is_wildcard; |
| 1313 | Sort_wildcard sort; |
| 1314 | |
| 1315 | Input_section_pattern(const char* patterna, size_t patternlena, |
| 1316 | Sort_wildcard sorta) |
| 1317 | : pattern(patterna, patternlena), |
| 1318 | pattern_is_wildcard(is_wildcard_string(this->pattern.c_str())), |
| 1319 | sort(sorta) |
| 1320 | { } |
| 1321 | }; |
| 1322 | |
| 1323 | typedef std::vector<Input_section_pattern> Input_section_patterns; |
| 1324 | |
| 1325 | // Filename_exclusions is a pair of filename pattern and a bool |
| 1326 | // indicating whether the filename is a wildcard. |
| 1327 | typedef std::vector<std::pair<std::string, bool> > Filename_exclusions; |
| 1328 | |
| 1329 | // Return whether STRING matches PATTERN, where IS_WILDCARD_PATTERN |
| 1330 | // indicates whether this is a wildcard pattern. |
| 1331 | static inline bool |
| 1332 | match(const char* string, const char* pattern, bool is_wildcard_pattern) |
| 1333 | { |
| 1334 | return (is_wildcard_pattern |
| 1335 | ? fnmatch(pattern, string, 0) == 0 |
| 1336 | : strcmp(string, pattern) == 0); |
| 1337 | } |
| 1338 | |
| 1339 | // See if we match a file name. |
| 1340 | bool |
| 1341 | match_file_name(const char* file_name) const; |
| 1342 | |
| 1343 | // The file name pattern. If this is the empty string, we match all |
| 1344 | // files. |
| 1345 | std::string filename_pattern_; |
| 1346 | // Whether the file name pattern is a wildcard. |
| 1347 | bool filename_is_wildcard_; |
| 1348 | // How the file names should be sorted. This may only be |
| 1349 | // SORT_WILDCARD_NONE or SORT_WILDCARD_BY_NAME. |
| 1350 | Sort_wildcard filename_sort_; |
| 1351 | // The list of file names to exclude. |
| 1352 | Filename_exclusions filename_exclusions_; |
| 1353 | // The list of input section patterns. |
| 1354 | Input_section_patterns input_section_patterns_; |
| 1355 | // Whether to keep this section when garbage collecting. |
| 1356 | bool keep_; |
| 1357 | // The value of dot after including all matching sections. |
| 1358 | uint64_t final_dot_value_; |
| 1359 | // The section where dot is defined after including all matching |
| 1360 | // sections. |
| 1361 | Output_section* final_dot_section_; |
| 1362 | }; |
| 1363 | |
| 1364 | // Construct Output_section_element_input. The parser records strings |
| 1365 | // as pointers into a copy of the script file, which will go away when |
| 1366 | // parsing is complete. We make sure they are in std::string objects. |
| 1367 | |
| 1368 | Output_section_element_input::Output_section_element_input( |
| 1369 | const Input_section_spec* spec, |
| 1370 | bool keep) |
| 1371 | : filename_pattern_(), |
| 1372 | filename_is_wildcard_(false), |
| 1373 | filename_sort_(spec->file.sort), |
| 1374 | filename_exclusions_(), |
| 1375 | input_section_patterns_(), |
| 1376 | keep_(keep), |
| 1377 | final_dot_value_(0), |
| 1378 | final_dot_section_(NULL) |
| 1379 | { |
| 1380 | // The filename pattern "*" is common, and matches all files. Turn |
| 1381 | // it into the empty string. |
| 1382 | if (spec->file.name.length != 1 || spec->file.name.value[0] != '*') |
| 1383 | this->filename_pattern_.assign(spec->file.name.value, |
| 1384 | spec->file.name.length); |
| 1385 | this->filename_is_wildcard_ = is_wildcard_string(this->filename_pattern_.c_str()); |
| 1386 | |
| 1387 | if (spec->input_sections.exclude != NULL) |
| 1388 | { |
| 1389 | for (String_list::const_iterator p = |
| 1390 | spec->input_sections.exclude->begin(); |
| 1391 | p != spec->input_sections.exclude->end(); |
| 1392 | ++p) |
| 1393 | { |
| 1394 | bool is_wildcard = is_wildcard_string((*p).c_str()); |
| 1395 | this->filename_exclusions_.push_back(std::make_pair(*p, |
| 1396 | is_wildcard)); |
| 1397 | } |
| 1398 | } |
| 1399 | |
| 1400 | if (spec->input_sections.sections != NULL) |
| 1401 | { |
| 1402 | Input_section_patterns& isp(this->input_section_patterns_); |
| 1403 | for (String_sort_list::const_iterator p = |
| 1404 | spec->input_sections.sections->begin(); |
| 1405 | p != spec->input_sections.sections->end(); |
| 1406 | ++p) |
| 1407 | isp.push_back(Input_section_pattern(p->name.value, p->name.length, |
| 1408 | p->sort)); |
| 1409 | } |
| 1410 | } |
| 1411 | |
| 1412 | // See whether we match FILE_NAME. |
| 1413 | |
| 1414 | bool |
| 1415 | Output_section_element_input::match_file_name(const char* file_name) const |
| 1416 | { |
| 1417 | if (!this->filename_pattern_.empty()) |
| 1418 | { |
| 1419 | // If we were called with no filename, we refuse to match a |
| 1420 | // pattern which requires a file name. |
| 1421 | if (file_name == NULL) |
| 1422 | return false; |
| 1423 | |
| 1424 | if (!match(file_name, this->filename_pattern_.c_str(), |
| 1425 | this->filename_is_wildcard_)) |
| 1426 | return false; |
| 1427 | } |
| 1428 | |
| 1429 | if (file_name != NULL) |
| 1430 | { |
| 1431 | // Now we have to see whether FILE_NAME matches one of the |
| 1432 | // exclusion patterns, if any. |
| 1433 | for (Filename_exclusions::const_iterator p = |
| 1434 | this->filename_exclusions_.begin(); |
| 1435 | p != this->filename_exclusions_.end(); |
| 1436 | ++p) |
| 1437 | { |
| 1438 | if (match(file_name, p->first.c_str(), p->second)) |
| 1439 | return false; |
| 1440 | } |
| 1441 | } |
| 1442 | |
| 1443 | return true; |
| 1444 | } |
| 1445 | |
| 1446 | // See whether we match FILE_NAME and SECTION_NAME. If we do then |
| 1447 | // KEEP indicates whether the section should survive garbage collection. |
| 1448 | |
| 1449 | bool |
| 1450 | Output_section_element_input::match_name(const char* file_name, |
| 1451 | const char* section_name, |
| 1452 | bool *keep) const |
| 1453 | { |
| 1454 | if (!this->match_file_name(file_name)) |
| 1455 | return false; |
| 1456 | |
| 1457 | *keep = this->keep_; |
| 1458 | |
| 1459 | // If there are no section name patterns, then we match. |
| 1460 | if (this->input_section_patterns_.empty()) |
| 1461 | return true; |
| 1462 | |
| 1463 | // See whether we match the section name patterns. |
| 1464 | for (Input_section_patterns::const_iterator p = |
| 1465 | this->input_section_patterns_.begin(); |
| 1466 | p != this->input_section_patterns_.end(); |
| 1467 | ++p) |
| 1468 | { |
| 1469 | if (match(section_name, p->pattern.c_str(), p->pattern_is_wildcard)) |
| 1470 | return true; |
| 1471 | } |
| 1472 | |
| 1473 | // We didn't match any section names, so we didn't match. |
| 1474 | return false; |
| 1475 | } |
| 1476 | |
| 1477 | // Information we use to sort the input sections. |
| 1478 | |
| 1479 | class Input_section_info |
| 1480 | { |
| 1481 | public: |
| 1482 | Input_section_info(const Output_section::Input_section& input_section) |
| 1483 | : input_section_(input_section), section_name_(), |
| 1484 | size_(0), addralign_(1) |
| 1485 | { } |
| 1486 | |
| 1487 | // Return the simple input section. |
| 1488 | const Output_section::Input_section& |
| 1489 | input_section() const |
| 1490 | { return this->input_section_; } |
| 1491 | |
| 1492 | // Return the object. |
| 1493 | Relobj* |
| 1494 | relobj() const |
| 1495 | { return this->input_section_.relobj(); } |
| 1496 | |
| 1497 | // Return the section index. |
| 1498 | unsigned int |
| 1499 | shndx() |
| 1500 | { return this->input_section_.shndx(); } |
| 1501 | |
| 1502 | // Return the section name. |
| 1503 | const std::string& |
| 1504 | section_name() const |
| 1505 | { return this->section_name_; } |
| 1506 | |
| 1507 | // Set the section name. |
| 1508 | void |
| 1509 | set_section_name(const std::string name) |
| 1510 | { |
| 1511 | if (is_compressed_debug_section(name.c_str())) |
| 1512 | this->section_name_ = corresponding_uncompressed_section_name(name); |
| 1513 | else |
| 1514 | this->section_name_ = name; |
| 1515 | } |
| 1516 | |
| 1517 | // Return the section size. |
| 1518 | uint64_t |
| 1519 | size() const |
| 1520 | { return this->size_; } |
| 1521 | |
| 1522 | // Set the section size. |
| 1523 | void |
| 1524 | set_size(uint64_t size) |
| 1525 | { this->size_ = size; } |
| 1526 | |
| 1527 | // Return the address alignment. |
| 1528 | uint64_t |
| 1529 | addralign() const |
| 1530 | { return this->addralign_; } |
| 1531 | |
| 1532 | // Set the address alignment. |
| 1533 | void |
| 1534 | set_addralign(uint64_t addralign) |
| 1535 | { this->addralign_ = addralign; } |
| 1536 | |
| 1537 | private: |
| 1538 | // Input section, can be a relaxed section. |
| 1539 | Output_section::Input_section input_section_; |
| 1540 | // Name of the section. |
| 1541 | std::string section_name_; |
| 1542 | // Section size. |
| 1543 | uint64_t size_; |
| 1544 | // Address alignment. |
| 1545 | uint64_t addralign_; |
| 1546 | }; |
| 1547 | |
| 1548 | // A class to sort the input sections. |
| 1549 | |
| 1550 | class Input_section_sorter |
| 1551 | { |
| 1552 | public: |
| 1553 | Input_section_sorter(Sort_wildcard filename_sort, Sort_wildcard section_sort) |
| 1554 | : filename_sort_(filename_sort), section_sort_(section_sort) |
| 1555 | { } |
| 1556 | |
| 1557 | bool |
| 1558 | operator()(const Input_section_info&, const Input_section_info&) const; |
| 1559 | |
| 1560 | private: |
| 1561 | static unsigned long |
| 1562 | get_init_priority(const char*); |
| 1563 | |
| 1564 | Sort_wildcard filename_sort_; |
| 1565 | Sort_wildcard section_sort_; |
| 1566 | }; |
| 1567 | |
| 1568 | // Return a relative priority of the section with the specified NAME |
| 1569 | // (a lower value meand a higher priority), or 0 if it should be compared |
| 1570 | // with others as strings. |
| 1571 | // The implementation of this function is copied from ld/ldlang.c. |
| 1572 | |
| 1573 | unsigned long |
| 1574 | Input_section_sorter::get_init_priority(const char* name) |
| 1575 | { |
| 1576 | char* end; |
| 1577 | unsigned long init_priority; |
| 1578 | |
| 1579 | // GCC uses the following section names for the init_priority |
| 1580 | // attribute with numerical values 101 and 65535 inclusive. A |
| 1581 | // lower value means a higher priority. |
| 1582 | // |
| 1583 | // 1: .init_array.NNNN/.fini_array.NNNN: Where NNNN is the |
| 1584 | // decimal numerical value of the init_priority attribute. |
| 1585 | // The order of execution in .init_array is forward and |
| 1586 | // .fini_array is backward. |
| 1587 | // 2: .ctors.NNNN/.dtors.NNNN: Where NNNN is 65535 minus the |
| 1588 | // decimal numerical value of the init_priority attribute. |
| 1589 | // The order of execution in .ctors is backward and .dtors |
| 1590 | // is forward. |
| 1591 | |
| 1592 | if (strncmp(name, ".init_array.", 12) == 0 |
| 1593 | || strncmp(name, ".fini_array.", 12) == 0) |
| 1594 | { |
| 1595 | init_priority = strtoul(name + 12, &end, 10); |
| 1596 | return *end ? 0 : init_priority; |
| 1597 | } |
| 1598 | else if (strncmp(name, ".ctors.", 7) == 0 |
| 1599 | || strncmp(name, ".dtors.", 7) == 0) |
| 1600 | { |
| 1601 | init_priority = strtoul(name + 7, &end, 10); |
| 1602 | return *end ? 0 : 65535 - init_priority; |
| 1603 | } |
| 1604 | |
| 1605 | return 0; |
| 1606 | } |
| 1607 | |
| 1608 | bool |
| 1609 | Input_section_sorter::operator()(const Input_section_info& isi1, |
| 1610 | const Input_section_info& isi2) const |
| 1611 | { |
| 1612 | if (this->section_sort_ == SORT_WILDCARD_BY_INIT_PRIORITY) |
| 1613 | { |
| 1614 | unsigned long ip1 = get_init_priority(isi1.section_name().c_str()); |
| 1615 | unsigned long ip2 = get_init_priority(isi2.section_name().c_str()); |
| 1616 | if (ip1 != 0 && ip2 != 0 && ip1 != ip2) |
| 1617 | return ip1 < ip2; |
| 1618 | } |
| 1619 | if (this->section_sort_ == SORT_WILDCARD_BY_NAME |
| 1620 | || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT |
| 1621 | || (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME |
| 1622 | && isi1.addralign() == isi2.addralign()) |
| 1623 | || this->section_sort_ == SORT_WILDCARD_BY_INIT_PRIORITY) |
| 1624 | { |
| 1625 | if (isi1.section_name() != isi2.section_name()) |
| 1626 | return isi1.section_name() < isi2.section_name(); |
| 1627 | } |
| 1628 | if (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT |
| 1629 | || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT |
| 1630 | || this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME) |
| 1631 | { |
| 1632 | if (isi1.addralign() != isi2.addralign()) |
| 1633 | return isi1.addralign() < isi2.addralign(); |
| 1634 | } |
| 1635 | if (this->filename_sort_ == SORT_WILDCARD_BY_NAME) |
| 1636 | { |
| 1637 | if (isi1.relobj()->name() != isi2.relobj()->name()) |
| 1638 | return (isi1.relobj()->name() < isi2.relobj()->name()); |
| 1639 | } |
| 1640 | |
| 1641 | // Otherwise we leave them in the same order. |
| 1642 | return false; |
| 1643 | } |
| 1644 | |
| 1645 | // Set the section address. Look in INPUT_SECTIONS for sections which |
| 1646 | // match this spec, sort them as specified, and add them to the output |
| 1647 | // section. |
| 1648 | |
| 1649 | void |
| 1650 | Output_section_element_input::set_section_addresses( |
| 1651 | Symbol_table*, |
| 1652 | Layout* layout, |
| 1653 | Output_section* output_section, |
| 1654 | uint64_t subalign, |
| 1655 | uint64_t* dot_value, |
| 1656 | uint64_t*, |
| 1657 | Output_section** dot_section, |
| 1658 | std::string* fill, |
| 1659 | Input_section_list* input_sections) |
| 1660 | { |
| 1661 | // We build a list of sections which match each |
| 1662 | // Input_section_pattern. |
| 1663 | |
| 1664 | // If none of the patterns specify a sort option, we throw all |
| 1665 | // matching input sections into a single bin, in the order we |
| 1666 | // find them. Otherwise, we put matching input sections into |
| 1667 | // a separate bin for each pattern, and sort each one as |
| 1668 | // specified. Thus, an input section spec like this: |
| 1669 | // *(.foo .bar) |
| 1670 | // will group all .foo and .bar sections in the order seen, |
| 1671 | // whereas this: |
| 1672 | // *(.foo) *(.bar) |
| 1673 | // will group all .foo sections followed by all .bar sections. |
| 1674 | // This matches Gnu ld behavior. |
| 1675 | |
| 1676 | // Things get really weird, though, when you add a sort spec |
| 1677 | // on some, but not all, of the patterns, like this: |
| 1678 | // *(SORT_BY_NAME(.foo) .bar) |
| 1679 | // We do not attempt to match Gnu ld behavior in this case. |
| 1680 | |
| 1681 | typedef std::vector<std::vector<Input_section_info> > Matching_sections; |
| 1682 | size_t input_pattern_count = this->input_section_patterns_.size(); |
| 1683 | size_t bin_count = 1; |
| 1684 | bool any_patterns_with_sort = false; |
| 1685 | for (size_t i = 0; i < input_pattern_count; ++i) |
| 1686 | { |
| 1687 | const Input_section_pattern& isp(this->input_section_patterns_[i]); |
| 1688 | if (isp.sort != SORT_WILDCARD_NONE) |
| 1689 | any_patterns_with_sort = true; |
| 1690 | } |
| 1691 | if (any_patterns_with_sort) |
| 1692 | bin_count = input_pattern_count; |
| 1693 | Matching_sections matching_sections(bin_count); |
| 1694 | |
| 1695 | // Look through the list of sections for this output section. Add |
| 1696 | // each one which matches to one of the elements of |
| 1697 | // MATCHING_SECTIONS. |
| 1698 | |
| 1699 | Input_section_list::iterator p = input_sections->begin(); |
| 1700 | while (p != input_sections->end()) |
| 1701 | { |
| 1702 | Relobj* relobj = p->relobj(); |
| 1703 | unsigned int shndx = p->shndx(); |
| 1704 | Input_section_info isi(*p); |
| 1705 | |
| 1706 | // Calling section_name and section_addralign is not very |
| 1707 | // efficient. |
| 1708 | |
| 1709 | // Lock the object so that we can get information about the |
| 1710 | // section. This is OK since we know we are single-threaded |
| 1711 | // here. |
| 1712 | { |
| 1713 | const Task* task = reinterpret_cast<const Task*>(-1); |
| 1714 | Task_lock_obj<Object> tl(task, relobj); |
| 1715 | |
| 1716 | isi.set_section_name(relobj->section_name(shndx)); |
| 1717 | if (p->is_relaxed_input_section()) |
| 1718 | { |
| 1719 | // We use current data size because relaxed section sizes may not |
| 1720 | // have finalized yet. |
| 1721 | isi.set_size(p->relaxed_input_section()->current_data_size()); |
| 1722 | isi.set_addralign(p->relaxed_input_section()->addralign()); |
| 1723 | } |
| 1724 | else |
| 1725 | { |
| 1726 | isi.set_size(relobj->section_size(shndx)); |
| 1727 | isi.set_addralign(relobj->section_addralign(shndx)); |
| 1728 | } |
| 1729 | } |
| 1730 | |
| 1731 | if (!this->match_file_name(relobj->name().c_str())) |
| 1732 | ++p; |
| 1733 | else if (this->input_section_patterns_.empty()) |
| 1734 | { |
| 1735 | matching_sections[0].push_back(isi); |
| 1736 | p = input_sections->erase(p); |
| 1737 | } |
| 1738 | else |
| 1739 | { |
| 1740 | size_t i; |
| 1741 | for (i = 0; i < input_pattern_count; ++i) |
| 1742 | { |
| 1743 | const Input_section_pattern& |
| 1744 | isp(this->input_section_patterns_[i]); |
| 1745 | if (match(isi.section_name().c_str(), isp.pattern.c_str(), |
| 1746 | isp.pattern_is_wildcard)) |
| 1747 | break; |
| 1748 | } |
| 1749 | |
| 1750 | if (i >= input_pattern_count) |
| 1751 | ++p; |
| 1752 | else |
| 1753 | { |
| 1754 | if (i >= bin_count) |
| 1755 | i = 0; |
| 1756 | matching_sections[i].push_back(isi); |
| 1757 | p = input_sections->erase(p); |
| 1758 | } |
| 1759 | } |
| 1760 | } |
| 1761 | |
| 1762 | // Look through MATCHING_SECTIONS. Sort each one as specified, |
| 1763 | // using a stable sort so that we get the default order when |
| 1764 | // sections are otherwise equal. Add each input section to the |
| 1765 | // output section. |
| 1766 | |
| 1767 | uint64_t dot = *dot_value; |
| 1768 | for (size_t i = 0; i < bin_count; ++i) |
| 1769 | { |
| 1770 | if (matching_sections[i].empty()) |
| 1771 | continue; |
| 1772 | |
| 1773 | gold_assert(output_section != NULL); |
| 1774 | |
| 1775 | const Input_section_pattern& isp(this->input_section_patterns_[i]); |
| 1776 | if (isp.sort != SORT_WILDCARD_NONE |
| 1777 | || this->filename_sort_ != SORT_WILDCARD_NONE) |
| 1778 | std::stable_sort(matching_sections[i].begin(), |
| 1779 | matching_sections[i].end(), |
| 1780 | Input_section_sorter(this->filename_sort_, |
| 1781 | isp.sort)); |
| 1782 | |
| 1783 | for (std::vector<Input_section_info>::const_iterator p = |
| 1784 | matching_sections[i].begin(); |
| 1785 | p != matching_sections[i].end(); |
| 1786 | ++p) |
| 1787 | { |
| 1788 | // Override the original address alignment if SUBALIGN is specified. |
| 1789 | // We need to make a copy of the input section to modify the |
| 1790 | // alignment. |
| 1791 | Output_section::Input_section sis(p->input_section()); |
| 1792 | |
| 1793 | uint64_t this_subalign = sis.addralign(); |
| 1794 | if (!sis.is_input_section()) |
| 1795 | sis.output_section_data()->finalize_data_size(); |
| 1796 | uint64_t data_size = sis.data_size(); |
| 1797 | if (subalign > 0) |
| 1798 | { |
| 1799 | this_subalign = subalign; |
| 1800 | sis.set_addralign(subalign); |
| 1801 | } |
| 1802 | |
| 1803 | uint64_t address = align_address(dot, this_subalign); |
| 1804 | |
| 1805 | if (address > dot && !fill->empty()) |
| 1806 | { |
| 1807 | section_size_type length = |
| 1808 | convert_to_section_size_type(address - dot); |
| 1809 | std::string this_fill = this->get_fill_string(fill, length); |
| 1810 | Output_section_data* posd = new Output_data_const(this_fill, 0); |
| 1811 | output_section->add_output_section_data(posd); |
| 1812 | layout->new_output_section_data_from_script(posd); |
| 1813 | } |
| 1814 | |
| 1815 | output_section->add_script_input_section(sis); |
| 1816 | dot = address + data_size; |
| 1817 | } |
| 1818 | } |
| 1819 | |
| 1820 | // An SHF_TLS/SHT_NOBITS section does not take up any |
| 1821 | // address space. |
| 1822 | if (output_section == NULL |
| 1823 | || (output_section->flags() & elfcpp::SHF_TLS) == 0 |
| 1824 | || output_section->type() != elfcpp::SHT_NOBITS) |
| 1825 | *dot_value = dot; |
| 1826 | |
| 1827 | this->final_dot_value_ = *dot_value; |
| 1828 | this->final_dot_section_ = *dot_section; |
| 1829 | } |
| 1830 | |
| 1831 | // Print for debugging. |
| 1832 | |
| 1833 | void |
| 1834 | Output_section_element_input::print(FILE* f) const |
| 1835 | { |
| 1836 | fprintf(f, " "); |
| 1837 | |
| 1838 | if (this->keep_) |
| 1839 | fprintf(f, "KEEP("); |
| 1840 | |
| 1841 | if (!this->filename_pattern_.empty()) |
| 1842 | { |
| 1843 | bool need_close_paren = false; |
| 1844 | switch (this->filename_sort_) |
| 1845 | { |
| 1846 | case SORT_WILDCARD_NONE: |
| 1847 | break; |
| 1848 | case SORT_WILDCARD_BY_NAME: |
| 1849 | fprintf(f, "SORT_BY_NAME("); |
| 1850 | need_close_paren = true; |
| 1851 | break; |
| 1852 | default: |
| 1853 | gold_unreachable(); |
| 1854 | } |
| 1855 | |
| 1856 | fprintf(f, "%s", this->filename_pattern_.c_str()); |
| 1857 | |
| 1858 | if (need_close_paren) |
| 1859 | fprintf(f, ")"); |
| 1860 | } |
| 1861 | |
| 1862 | if (!this->input_section_patterns_.empty() |
| 1863 | || !this->filename_exclusions_.empty()) |
| 1864 | { |
| 1865 | fprintf(f, "("); |
| 1866 | |
| 1867 | bool need_space = false; |
| 1868 | if (!this->filename_exclusions_.empty()) |
| 1869 | { |
| 1870 | fprintf(f, "EXCLUDE_FILE("); |
| 1871 | bool need_comma = false; |
| 1872 | for (Filename_exclusions::const_iterator p = |
| 1873 | this->filename_exclusions_.begin(); |
| 1874 | p != this->filename_exclusions_.end(); |
| 1875 | ++p) |
| 1876 | { |
| 1877 | if (need_comma) |
| 1878 | fprintf(f, ", "); |
| 1879 | fprintf(f, "%s", p->first.c_str()); |
| 1880 | need_comma = true; |
| 1881 | } |
| 1882 | fprintf(f, ")"); |
| 1883 | need_space = true; |
| 1884 | } |
| 1885 | |
| 1886 | for (Input_section_patterns::const_iterator p = |
| 1887 | this->input_section_patterns_.begin(); |
| 1888 | p != this->input_section_patterns_.end(); |
| 1889 | ++p) |
| 1890 | { |
| 1891 | if (need_space) |
| 1892 | fprintf(f, " "); |
| 1893 | |
| 1894 | int close_parens = 0; |
| 1895 | switch (p->sort) |
| 1896 | { |
| 1897 | case SORT_WILDCARD_NONE: |
| 1898 | break; |
| 1899 | case SORT_WILDCARD_BY_NAME: |
| 1900 | fprintf(f, "SORT_BY_NAME("); |
| 1901 | close_parens = 1; |
| 1902 | break; |
| 1903 | case SORT_WILDCARD_BY_ALIGNMENT: |
| 1904 | fprintf(f, "SORT_BY_ALIGNMENT("); |
| 1905 | close_parens = 1; |
| 1906 | break; |
| 1907 | case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT: |
| 1908 | fprintf(f, "SORT_BY_NAME(SORT_BY_ALIGNMENT("); |
| 1909 | close_parens = 2; |
| 1910 | break; |
| 1911 | case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME: |
| 1912 | fprintf(f, "SORT_BY_ALIGNMENT(SORT_BY_NAME("); |
| 1913 | close_parens = 2; |
| 1914 | break; |
| 1915 | case SORT_WILDCARD_BY_INIT_PRIORITY: |
| 1916 | fprintf(f, "SORT_BY_INIT_PRIORITY("); |
| 1917 | close_parens = 1; |
| 1918 | break; |
| 1919 | default: |
| 1920 | gold_unreachable(); |
| 1921 | } |
| 1922 | |
| 1923 | fprintf(f, "%s", p->pattern.c_str()); |
| 1924 | |
| 1925 | for (int i = 0; i < close_parens; ++i) |
| 1926 | fprintf(f, ")"); |
| 1927 | |
| 1928 | need_space = true; |
| 1929 | } |
| 1930 | |
| 1931 | fprintf(f, ")"); |
| 1932 | } |
| 1933 | |
| 1934 | if (this->keep_) |
| 1935 | fprintf(f, ")"); |
| 1936 | |
| 1937 | fprintf(f, "\n"); |
| 1938 | } |
| 1939 | |
| 1940 | // An output section. |
| 1941 | |
| 1942 | class Output_section_definition : public Sections_element |
| 1943 | { |
| 1944 | public: |
| 1945 | typedef Output_section_element::Input_section_list Input_section_list; |
| 1946 | |
| 1947 | Output_section_definition(const char* name, size_t namelen, |
| 1948 | const Parser_output_section_header* header); |
| 1949 | |
| 1950 | // Finish the output section with the information in the trailer. |
| 1951 | void |
| 1952 | finish(const Parser_output_section_trailer* trailer); |
| 1953 | |
| 1954 | // Add a symbol to be defined. |
| 1955 | void |
| 1956 | add_symbol_assignment(const char* name, size_t length, Expression* value, |
| 1957 | bool provide, bool hidden); |
| 1958 | |
| 1959 | // Add an assignment to the special dot symbol. |
| 1960 | void |
| 1961 | add_dot_assignment(Expression* value); |
| 1962 | |
| 1963 | // Add an assertion. |
| 1964 | void |
| 1965 | add_assertion(Expression* check, const char* message, size_t messagelen); |
| 1966 | |
| 1967 | // Add a data item to the current output section. |
| 1968 | void |
| 1969 | add_data(int size, bool is_signed, Expression* val); |
| 1970 | |
| 1971 | // Add a setting for the fill value. |
| 1972 | void |
| 1973 | add_fill(Expression* val); |
| 1974 | |
| 1975 | // Add an input section specification. |
| 1976 | void |
| 1977 | add_input_section(const Input_section_spec* spec, bool keep); |
| 1978 | |
| 1979 | // Return whether the output section is relro. |
| 1980 | bool |
| 1981 | is_relro() const |
| 1982 | { return this->is_relro_; } |
| 1983 | |
| 1984 | // Record that the output section is relro. |
| 1985 | void |
| 1986 | set_is_relro() |
| 1987 | { this->is_relro_ = true; } |
| 1988 | |
| 1989 | // Create any required output sections. |
| 1990 | void |
| 1991 | create_sections(Layout*); |
| 1992 | |
| 1993 | // Add any symbols being defined to the symbol table. |
| 1994 | void |
| 1995 | add_symbols_to_table(Symbol_table* symtab); |
| 1996 | |
| 1997 | // Finalize symbols and check assertions. |
| 1998 | void |
| 1999 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*); |
| 2000 | |
| 2001 | // Return the output section name to use for an input file name and |
| 2002 | // section name. |
| 2003 | const char* |
| 2004 | output_section_name(const char* file_name, const char* section_name, |
| 2005 | Output_section***, Script_sections::Section_type*, |
| 2006 | bool*, bool); |
| 2007 | |
| 2008 | // Initialize OSP with an output section. |
| 2009 | void |
| 2010 | orphan_section_init(Orphan_section_placement* osp, |
| 2011 | Script_sections::Elements_iterator p) |
| 2012 | { osp->output_section_init(this->name_, this->output_section_, p); } |
| 2013 | |
| 2014 | // Set the section address. |
| 2015 | void |
| 2016 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 2017 | uint64_t* dot_value, uint64_t*, |
| 2018 | uint64_t* load_address); |
| 2019 | |
| 2020 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 2021 | // this section is constrained, and the input sections do not match, |
| 2022 | // return the constraint, and set *POSD. |
| 2023 | Section_constraint |
| 2024 | check_constraint(Output_section_definition** posd); |
| 2025 | |
| 2026 | // See if this is the alternate output section for a constrained |
| 2027 | // output section. If it is, transfer the Output_section and return |
| 2028 | // true. Otherwise return false. |
| 2029 | bool |
| 2030 | alternate_constraint(Output_section_definition*, Section_constraint); |
| 2031 | |
| 2032 | // Get the list of segments to use for an allocated section when |
| 2033 | // using a PHDRS clause. |
| 2034 | Output_section* |
| 2035 | allocate_to_segment(String_list** phdrs_list, bool* orphan); |
| 2036 | |
| 2037 | // Look for an output section by name and return the address, the |
| 2038 | // load address, the alignment, and the size. This is used when an |
| 2039 | // expression refers to an output section which was not actually |
| 2040 | // created. This returns true if the section was found, false |
| 2041 | // otherwise. |
| 2042 | bool |
| 2043 | get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| 2044 | uint64_t*) const; |
| 2045 | |
| 2046 | // Return the associated Output_section if there is one. |
| 2047 | Output_section* |
| 2048 | get_output_section() const |
| 2049 | { return this->output_section_; } |
| 2050 | |
| 2051 | // Print the contents to the FILE. This is for debugging. |
| 2052 | void |
| 2053 | print(FILE*) const; |
| 2054 | |
| 2055 | // Return the output section type if specified or Script_sections::ST_NONE. |
| 2056 | Script_sections::Section_type |
| 2057 | section_type() const; |
| 2058 | |
| 2059 | // Store the memory region to use. |
| 2060 | void |
| 2061 | set_memory_region(Memory_region*, bool set_vma); |
| 2062 | |
| 2063 | void |
| 2064 | set_section_vma(Expression* address) |
| 2065 | { this->address_ = address; } |
| 2066 | |
| 2067 | void |
| 2068 | set_section_lma(Expression* address) |
| 2069 | { this->load_address_ = address; } |
| 2070 | |
| 2071 | const std::string& |
| 2072 | get_section_name() const |
| 2073 | { return this->name_; } |
| 2074 | |
| 2075 | private: |
| 2076 | static const char* |
| 2077 | script_section_type_name(Script_section_type); |
| 2078 | |
| 2079 | typedef std::vector<Output_section_element*> Output_section_elements; |
| 2080 | |
| 2081 | // The output section name. |
| 2082 | std::string name_; |
| 2083 | // The address. This may be NULL. |
| 2084 | Expression* address_; |
| 2085 | // The load address. This may be NULL. |
| 2086 | Expression* load_address_; |
| 2087 | // The alignment. This may be NULL. |
| 2088 | Expression* align_; |
| 2089 | // The input section alignment. This may be NULL. |
| 2090 | Expression* subalign_; |
| 2091 | // The constraint, if any. |
| 2092 | Section_constraint constraint_; |
| 2093 | // The fill value. This may be NULL. |
| 2094 | Expression* fill_; |
| 2095 | // The list of segments this section should go into. This may be |
| 2096 | // NULL. |
| 2097 | String_list* phdrs_; |
| 2098 | // The list of elements defining the section. |
| 2099 | Output_section_elements elements_; |
| 2100 | // The Output_section created for this definition. This will be |
| 2101 | // NULL if none was created. |
| 2102 | Output_section* output_section_; |
| 2103 | // The address after it has been evaluated. |
| 2104 | uint64_t evaluated_address_; |
| 2105 | // The load address after it has been evaluated. |
| 2106 | uint64_t evaluated_load_address_; |
| 2107 | // The alignment after it has been evaluated. |
| 2108 | uint64_t evaluated_addralign_; |
| 2109 | // The output section is relro. |
| 2110 | bool is_relro_; |
| 2111 | // The output section type if specified. |
| 2112 | enum Script_section_type script_section_type_; |
| 2113 | }; |
| 2114 | |
| 2115 | // Constructor. |
| 2116 | |
| 2117 | Output_section_definition::Output_section_definition( |
| 2118 | const char* name, |
| 2119 | size_t namelen, |
| 2120 | const Parser_output_section_header* header) |
| 2121 | : name_(name, namelen), |
| 2122 | address_(header->address), |
| 2123 | load_address_(header->load_address), |
| 2124 | align_(header->align), |
| 2125 | subalign_(header->subalign), |
| 2126 | constraint_(header->constraint), |
| 2127 | fill_(NULL), |
| 2128 | phdrs_(NULL), |
| 2129 | elements_(), |
| 2130 | output_section_(NULL), |
| 2131 | evaluated_address_(0), |
| 2132 | evaluated_load_address_(0), |
| 2133 | evaluated_addralign_(0), |
| 2134 | is_relro_(false), |
| 2135 | script_section_type_(header->section_type) |
| 2136 | { |
| 2137 | } |
| 2138 | |
| 2139 | // Finish an output section. |
| 2140 | |
| 2141 | void |
| 2142 | Output_section_definition::finish(const Parser_output_section_trailer* trailer) |
| 2143 | { |
| 2144 | this->fill_ = trailer->fill; |
| 2145 | this->phdrs_ = trailer->phdrs; |
| 2146 | } |
| 2147 | |
| 2148 | // Add a symbol to be defined. |
| 2149 | |
| 2150 | void |
| 2151 | Output_section_definition::add_symbol_assignment(const char* name, |
| 2152 | size_t length, |
| 2153 | Expression* value, |
| 2154 | bool provide, |
| 2155 | bool hidden) |
| 2156 | { |
| 2157 | Output_section_element* p = new Output_section_element_assignment(name, |
| 2158 | length, |
| 2159 | value, |
| 2160 | provide, |
| 2161 | hidden); |
| 2162 | this->elements_.push_back(p); |
| 2163 | } |
| 2164 | |
| 2165 | // Add an assignment to the special dot symbol. |
| 2166 | |
| 2167 | void |
| 2168 | Output_section_definition::add_dot_assignment(Expression* value) |
| 2169 | { |
| 2170 | Output_section_element* p = new Output_section_element_dot_assignment(value); |
| 2171 | this->elements_.push_back(p); |
| 2172 | } |
| 2173 | |
| 2174 | // Add an assertion. |
| 2175 | |
| 2176 | void |
| 2177 | Output_section_definition::add_assertion(Expression* check, |
| 2178 | const char* message, |
| 2179 | size_t messagelen) |
| 2180 | { |
| 2181 | Output_section_element* p = new Output_section_element_assertion(check, |
| 2182 | message, |
| 2183 | messagelen); |
| 2184 | this->elements_.push_back(p); |
| 2185 | } |
| 2186 | |
| 2187 | // Add a data item to the current output section. |
| 2188 | |
| 2189 | void |
| 2190 | Output_section_definition::add_data(int size, bool is_signed, Expression* val) |
| 2191 | { |
| 2192 | Output_section_element* p = new Output_section_element_data(size, is_signed, |
| 2193 | val); |
| 2194 | this->elements_.push_back(p); |
| 2195 | } |
| 2196 | |
| 2197 | // Add a setting for the fill value. |
| 2198 | |
| 2199 | void |
| 2200 | Output_section_definition::add_fill(Expression* val) |
| 2201 | { |
| 2202 | Output_section_element* p = new Output_section_element_fill(val); |
| 2203 | this->elements_.push_back(p); |
| 2204 | } |
| 2205 | |
| 2206 | // Add an input section specification. |
| 2207 | |
| 2208 | void |
| 2209 | Output_section_definition::add_input_section(const Input_section_spec* spec, |
| 2210 | bool keep) |
| 2211 | { |
| 2212 | Output_section_element* p = new Output_section_element_input(spec, keep); |
| 2213 | this->elements_.push_back(p); |
| 2214 | } |
| 2215 | |
| 2216 | // Create any required output sections. We need an output section if |
| 2217 | // there is a data statement here. |
| 2218 | |
| 2219 | void |
| 2220 | Output_section_definition::create_sections(Layout* layout) |
| 2221 | { |
| 2222 | if (this->output_section_ != NULL) |
| 2223 | return; |
| 2224 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 2225 | p != this->elements_.end(); |
| 2226 | ++p) |
| 2227 | { |
| 2228 | if ((*p)->needs_output_section()) |
| 2229 | { |
| 2230 | const char* name = this->name_.c_str(); |
| 2231 | this->output_section_ = |
| 2232 | layout->make_output_section_for_script(name, this->section_type()); |
| 2233 | return; |
| 2234 | } |
| 2235 | } |
| 2236 | } |
| 2237 | |
| 2238 | // Add any symbols being defined to the symbol table. |
| 2239 | |
| 2240 | void |
| 2241 | Output_section_definition::add_symbols_to_table(Symbol_table* symtab) |
| 2242 | { |
| 2243 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 2244 | p != this->elements_.end(); |
| 2245 | ++p) |
| 2246 | (*p)->add_symbols_to_table(symtab); |
| 2247 | } |
| 2248 | |
| 2249 | // Finalize symbols and check assertions. |
| 2250 | |
| 2251 | void |
| 2252 | Output_section_definition::finalize_symbols(Symbol_table* symtab, |
| 2253 | const Layout* layout, |
| 2254 | uint64_t* dot_value) |
| 2255 | { |
| 2256 | if (this->output_section_ != NULL) |
| 2257 | *dot_value = this->output_section_->address(); |
| 2258 | else |
| 2259 | { |
| 2260 | uint64_t address = *dot_value; |
| 2261 | if (this->address_ != NULL) |
| 2262 | { |
| 2263 | address = this->address_->eval_with_dot(symtab, layout, true, |
| 2264 | *dot_value, NULL, |
| 2265 | NULL, NULL, false); |
| 2266 | } |
| 2267 | if (this->align_ != NULL) |
| 2268 | { |
| 2269 | uint64_t align = this->align_->eval_with_dot(symtab, layout, true, |
| 2270 | *dot_value, NULL, |
| 2271 | NULL, NULL, false); |
| 2272 | address = align_address(address, align); |
| 2273 | } |
| 2274 | *dot_value = address; |
| 2275 | } |
| 2276 | |
| 2277 | Output_section* dot_section = this->output_section_; |
| 2278 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 2279 | p != this->elements_.end(); |
| 2280 | ++p) |
| 2281 | (*p)->finalize_symbols(symtab, layout, dot_value, &dot_section); |
| 2282 | } |
| 2283 | |
| 2284 | // Return the output section name to use for an input section name. |
| 2285 | |
| 2286 | const char* |
| 2287 | Output_section_definition::output_section_name( |
| 2288 | const char* file_name, |
| 2289 | const char* section_name, |
| 2290 | Output_section*** slot, |
| 2291 | Script_sections::Section_type* psection_type, |
| 2292 | bool* keep, |
| 2293 | bool match_input_spec) |
| 2294 | { |
| 2295 | // If the section is a linker-created output section, just look for a match |
| 2296 | // on the output section name. |
| 2297 | if (!match_input_spec && this->name_ != "/DISCARD/") |
| 2298 | { |
| 2299 | if (this->name_ != section_name) |
| 2300 | return NULL; |
| 2301 | *slot = &this->output_section_; |
| 2302 | *psection_type = this->section_type(); |
| 2303 | return this->name_.c_str(); |
| 2304 | } |
| 2305 | |
| 2306 | // Ask each element whether it matches NAME. |
| 2307 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 2308 | p != this->elements_.end(); |
| 2309 | ++p) |
| 2310 | { |
| 2311 | if ((*p)->match_name(file_name, section_name, keep)) |
| 2312 | { |
| 2313 | // We found a match for NAME, which means that it should go |
| 2314 | // into this output section. |
| 2315 | *slot = &this->output_section_; |
| 2316 | *psection_type = this->section_type(); |
| 2317 | return this->name_.c_str(); |
| 2318 | } |
| 2319 | } |
| 2320 | |
| 2321 | // We don't know about this section name. |
| 2322 | return NULL; |
| 2323 | } |
| 2324 | |
| 2325 | // Return true if memory from START to START + LENGTH is contained |
| 2326 | // within a memory region. |
| 2327 | |
| 2328 | bool |
| 2329 | Script_sections::block_in_region(Symbol_table* symtab, Layout* layout, |
| 2330 | uint64_t start, uint64_t length) const |
| 2331 | { |
| 2332 | if (this->memory_regions_ == NULL) |
| 2333 | return false; |
| 2334 | |
| 2335 | for (Memory_regions::const_iterator mr = this->memory_regions_->begin(); |
| 2336 | mr != this->memory_regions_->end(); |
| 2337 | ++mr) |
| 2338 | { |
| 2339 | uint64_t s = (*mr)->start_address()->eval(symtab, layout, false); |
| 2340 | uint64_t l = (*mr)->length()->eval(symtab, layout, false); |
| 2341 | |
| 2342 | if (s <= start |
| 2343 | && (s + l) >= (start + length)) |
| 2344 | return true; |
| 2345 | } |
| 2346 | |
| 2347 | return false; |
| 2348 | } |
| 2349 | |
| 2350 | // Find a memory region that should be used by a given output SECTION. |
| 2351 | // If provided set PREVIOUS_SECTION_RETURN to point to the last section |
| 2352 | // that used the return memory region. |
| 2353 | |
| 2354 | Memory_region* |
| 2355 | Script_sections::find_memory_region( |
| 2356 | Output_section_definition* section, |
| 2357 | bool find_vma_region, |
| 2358 | bool explicit_only, |
| 2359 | Output_section_definition** previous_section_return) |
| 2360 | { |
| 2361 | if (previous_section_return != NULL) |
| 2362 | * previous_section_return = NULL; |
| 2363 | |
| 2364 | // Walk the memory regions specified in this script, if any. |
| 2365 | if (this->memory_regions_ == NULL) |
| 2366 | return NULL; |
| 2367 | |
| 2368 | // The /DISCARD/ section never gets assigned to any region. |
| 2369 | if (section->get_section_name() == "/DISCARD/") |
| 2370 | return NULL; |
| 2371 | |
| 2372 | Memory_region* first_match = NULL; |
| 2373 | |
| 2374 | // First check to see if a region has been assigned to this section. |
| 2375 | for (Memory_regions::const_iterator mr = this->memory_regions_->begin(); |
| 2376 | mr != this->memory_regions_->end(); |
| 2377 | ++mr) |
| 2378 | { |
| 2379 | if (find_vma_region) |
| 2380 | { |
| 2381 | for (Memory_region::Section_list::const_iterator s = |
| 2382 | (*mr)->get_vma_section_list_start(); |
| 2383 | s != (*mr)->get_vma_section_list_end(); |
| 2384 | ++s) |
| 2385 | if ((*s) == section) |
| 2386 | { |
| 2387 | (*mr)->set_last_section(section); |
| 2388 | return *mr; |
| 2389 | } |
| 2390 | } |
| 2391 | else |
| 2392 | { |
| 2393 | for (Memory_region::Section_list::const_iterator s = |
| 2394 | (*mr)->get_lma_section_list_start(); |
| 2395 | s != (*mr)->get_lma_section_list_end(); |
| 2396 | ++s) |
| 2397 | if ((*s) == section) |
| 2398 | { |
| 2399 | (*mr)->set_last_section(section); |
| 2400 | return *mr; |
| 2401 | } |
| 2402 | } |
| 2403 | |
| 2404 | if (!explicit_only) |
| 2405 | { |
| 2406 | // Make a note of the first memory region whose attributes |
| 2407 | // are compatible with the section. If we do not find an |
| 2408 | // explicit region assignment, then we will return this region. |
| 2409 | Output_section* out_sec = section->get_output_section(); |
| 2410 | if (first_match == NULL |
| 2411 | && out_sec != NULL |
| 2412 | && (*mr)->attributes_compatible(out_sec->flags(), |
| 2413 | out_sec->type())) |
| 2414 | first_match = *mr; |
| 2415 | } |
| 2416 | } |
| 2417 | |
| 2418 | // With LMA computations, if an explicit region has not been specified then |
| 2419 | // we will want to set the difference between the VMA and the LMA of the |
| 2420 | // section were searching for to be the same as the difference between the |
| 2421 | // VMA and LMA of the last section to be added to first matched region. |
| 2422 | // Hence, if it was asked for, we return a pointer to the last section |
| 2423 | // known to be used by the first matched region. |
| 2424 | if (first_match != NULL |
| 2425 | && previous_section_return != NULL) |
| 2426 | *previous_section_return = first_match->get_last_section(); |
| 2427 | |
| 2428 | return first_match; |
| 2429 | } |
| 2430 | |
| 2431 | // Set the section address. Note that the OUTPUT_SECTION_ field will |
| 2432 | // be NULL if no input sections were mapped to this output section. |
| 2433 | // We still have to adjust dot and process symbol assignments. |
| 2434 | |
| 2435 | void |
| 2436 | Output_section_definition::set_section_addresses(Symbol_table* symtab, |
| 2437 | Layout* layout, |
| 2438 | uint64_t* dot_value, |
| 2439 | uint64_t* dot_alignment, |
| 2440 | uint64_t* load_address) |
| 2441 | { |
| 2442 | Memory_region* vma_region = NULL; |
| 2443 | Memory_region* lma_region = NULL; |
| 2444 | Script_sections* script_sections = |
| 2445 | layout->script_options()->script_sections(); |
| 2446 | uint64_t address; |
| 2447 | uint64_t old_dot_value = *dot_value; |
| 2448 | uint64_t old_load_address = *load_address; |
| 2449 | |
| 2450 | // If input section sorting is requested via --section-ordering-file or |
| 2451 | // linker plugins, then do it here. This is important because we want |
| 2452 | // any sorting specified in the linker scripts, which will be done after |
| 2453 | // this, to take precedence. The final order of input sections is then |
| 2454 | // guaranteed to be according to the linker script specification. |
| 2455 | if (this->output_section_ != NULL |
| 2456 | && this->output_section_->input_section_order_specified()) |
| 2457 | this->output_section_->sort_attached_input_sections(); |
| 2458 | |
| 2459 | // Decide the start address for the section. The algorithm is: |
| 2460 | // 1) If an address has been specified in a linker script, use that. |
| 2461 | // 2) Otherwise if a memory region has been specified for the section, |
| 2462 | // use the next free address in the region. |
| 2463 | // 3) Otherwise if memory regions have been specified find the first |
| 2464 | // region whose attributes are compatible with this section and |
| 2465 | // install it into that region. |
| 2466 | // 4) Otherwise use the current location counter. |
| 2467 | |
| 2468 | if (this->output_section_ != NULL |
| 2469 | // Check for --section-start. |
| 2470 | && parameters->options().section_start(this->output_section_->name(), |
| 2471 | &address)) |
| 2472 | ; |
| 2473 | else if (this->address_ == NULL) |
| 2474 | { |
| 2475 | vma_region = script_sections->find_memory_region(this, true, false, NULL); |
| 2476 | if (vma_region != NULL) |
| 2477 | address = vma_region->get_current_address()->eval(symtab, layout, |
| 2478 | false); |
| 2479 | else |
| 2480 | address = *dot_value; |
| 2481 | } |
| 2482 | else |
| 2483 | { |
| 2484 | vma_region = script_sections->find_memory_region(this, true, true, NULL); |
| 2485 | address = this->address_->eval_with_dot(symtab, layout, true, |
| 2486 | *dot_value, NULL, NULL, |
| 2487 | dot_alignment, false); |
| 2488 | if (vma_region != NULL) |
| 2489 | vma_region->set_address(address, symtab, layout); |
| 2490 | } |
| 2491 | |
| 2492 | uint64_t align; |
| 2493 | if (this->align_ == NULL) |
| 2494 | { |
| 2495 | if (this->output_section_ == NULL) |
| 2496 | align = 0; |
| 2497 | else |
| 2498 | align = this->output_section_->addralign(); |
| 2499 | } |
| 2500 | else |
| 2501 | { |
| 2502 | Output_section* align_section; |
| 2503 | align = this->align_->eval_with_dot(symtab, layout, true, *dot_value, |
| 2504 | NULL, &align_section, NULL, false); |
| 2505 | if (align_section != NULL) |
| 2506 | gold_warning(_("alignment of section %s is not absolute"), |
| 2507 | this->name_.c_str()); |
| 2508 | if (this->output_section_ != NULL) |
| 2509 | this->output_section_->set_addralign(align); |
| 2510 | } |
| 2511 | |
| 2512 | uint64_t subalign; |
| 2513 | if (this->subalign_ == NULL) |
| 2514 | subalign = 0; |
| 2515 | else |
| 2516 | { |
| 2517 | Output_section* subalign_section; |
| 2518 | subalign = this->subalign_->eval_with_dot(symtab, layout, true, |
| 2519 | *dot_value, NULL, |
| 2520 | &subalign_section, NULL, |
| 2521 | false); |
| 2522 | if (subalign_section != NULL) |
| 2523 | gold_warning(_("subalign of section %s is not absolute"), |
| 2524 | this->name_.c_str()); |
| 2525 | |
| 2526 | // Reserve a value of 0 to mean there is no SUBALIGN property. |
| 2527 | if (subalign == 0) |
| 2528 | subalign = 1; |
| 2529 | |
| 2530 | // The external alignment of the output section must be at least |
| 2531 | // as large as that of the input sections. If there is no |
| 2532 | // explicit ALIGN property, we set the output section alignment |
| 2533 | // to match the input section alignment. |
| 2534 | if (align < subalign || this->align_ == NULL) |
| 2535 | { |
| 2536 | align = subalign; |
| 2537 | this->output_section_->set_addralign(align); |
| 2538 | } |
| 2539 | } |
| 2540 | |
| 2541 | address = align_address(address, align); |
| 2542 | |
| 2543 | uint64_t start_address = address; |
| 2544 | |
| 2545 | *dot_value = address; |
| 2546 | |
| 2547 | // Except for NOLOAD sections, the address of non-SHF_ALLOC sections is |
| 2548 | // forced to zero, regardless of what the linker script wants. |
| 2549 | if (this->output_section_ != NULL |
| 2550 | && ((this->output_section_->flags() & elfcpp::SHF_ALLOC) != 0 |
| 2551 | || this->output_section_->is_noload())) |
| 2552 | this->output_section_->set_address(address); |
| 2553 | |
| 2554 | this->evaluated_address_ = address; |
| 2555 | this->evaluated_addralign_ = align; |
| 2556 | |
| 2557 | uint64_t laddr; |
| 2558 | |
| 2559 | if (this->load_address_ == NULL) |
| 2560 | { |
| 2561 | Output_section_definition* previous_section; |
| 2562 | |
| 2563 | // Determine if an LMA region has been set for this section. |
| 2564 | lma_region = script_sections->find_memory_region(this, false, false, |
| 2565 | &previous_section); |
| 2566 | |
| 2567 | if (lma_region != NULL) |
| 2568 | { |
| 2569 | if (previous_section == NULL) |
| 2570 | // The LMA address was explicitly set to the given region. |
| 2571 | laddr = lma_region->get_current_address()->eval(symtab, layout, |
| 2572 | false); |
| 2573 | else |
| 2574 | { |
| 2575 | // We are not going to use the discovered lma_region, so |
| 2576 | // make sure that we do not update it in the code below. |
| 2577 | lma_region = NULL; |
| 2578 | |
| 2579 | if (this->address_ != NULL || previous_section == this) |
| 2580 | { |
| 2581 | // Either an explicit VMA address has been set, or an |
| 2582 | // explicit VMA region has been set, so set the LMA equal to |
| 2583 | // the VMA. |
| 2584 | laddr = address; |
| 2585 | } |
| 2586 | else |
| 2587 | { |
| 2588 | // The LMA address was not explicitly or implicitly set. |
| 2589 | // |
| 2590 | // We have been given the first memory region that is |
| 2591 | // compatible with the current section and a pointer to the |
| 2592 | // last section to use this region. Set the LMA of this |
| 2593 | // section so that the difference between its' VMA and LMA |
| 2594 | // is the same as the difference between the VMA and LMA of |
| 2595 | // the last section in the given region. |
| 2596 | laddr = address + (previous_section->evaluated_load_address_ |
| 2597 | - previous_section->evaluated_address_); |
| 2598 | } |
| 2599 | } |
| 2600 | |
| 2601 | if (this->output_section_ != NULL) |
| 2602 | this->output_section_->set_load_address(laddr); |
| 2603 | } |
| 2604 | else |
| 2605 | { |
| 2606 | // Do not set the load address of the output section, if one exists. |
| 2607 | // This allows future sections to determine what the load address |
| 2608 | // should be. If none is ever set, it will default to being the |
| 2609 | // same as the vma address. |
| 2610 | laddr = address; |
| 2611 | } |
| 2612 | } |
| 2613 | else |
| 2614 | { |
| 2615 | laddr = this->load_address_->eval_with_dot(symtab, layout, true, |
| 2616 | *dot_value, |
| 2617 | this->output_section_, |
| 2618 | NULL, NULL, false); |
| 2619 | if (this->output_section_ != NULL) |
| 2620 | this->output_section_->set_load_address(laddr); |
| 2621 | } |
| 2622 | |
| 2623 | this->evaluated_load_address_ = laddr; |
| 2624 | |
| 2625 | std::string fill; |
| 2626 | if (this->fill_ != NULL) |
| 2627 | { |
| 2628 | // FIXME: The GNU linker supports fill values of arbitrary |
| 2629 | // length. |
| 2630 | Output_section* fill_section; |
| 2631 | uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout, true, |
| 2632 | *dot_value, |
| 2633 | NULL, &fill_section, |
| 2634 | NULL, false); |
| 2635 | if (fill_section != NULL) |
| 2636 | gold_warning(_("fill of section %s is not absolute"), |
| 2637 | this->name_.c_str()); |
| 2638 | unsigned char fill_buff[4]; |
| 2639 | elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| 2640 | fill.assign(reinterpret_cast<char*>(fill_buff), 4); |
| 2641 | } |
| 2642 | |
| 2643 | Input_section_list input_sections; |
| 2644 | if (this->output_section_ != NULL) |
| 2645 | { |
| 2646 | // Get the list of input sections attached to this output |
| 2647 | // section. This will leave the output section with only |
| 2648 | // Output_section_data entries. |
| 2649 | address += this->output_section_->get_input_sections(address, |
| 2650 | fill, |
| 2651 | &input_sections); |
| 2652 | *dot_value = address; |
| 2653 | } |
| 2654 | |
| 2655 | Output_section* dot_section = this->output_section_; |
| 2656 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 2657 | p != this->elements_.end(); |
| 2658 | ++p) |
| 2659 | (*p)->set_section_addresses(symtab, layout, this->output_section_, |
| 2660 | subalign, dot_value, dot_alignment, |
| 2661 | &dot_section, &fill, &input_sections); |
| 2662 | |
| 2663 | gold_assert(input_sections.empty()); |
| 2664 | |
| 2665 | if (vma_region != NULL) |
| 2666 | { |
| 2667 | // Update the VMA region being used by the section now that we know how |
| 2668 | // big it is. Use the current address in the region, rather than |
| 2669 | // start_address because that might have been aligned upwards and we |
| 2670 | // need to allow for the padding. |
| 2671 | Expression* addr = vma_region->get_current_address(); |
| 2672 | uint64_t size = *dot_value - addr->eval(symtab, layout, false); |
| 2673 | |
| 2674 | vma_region->increment_offset(this->get_section_name(), size, |
| 2675 | symtab, layout); |
| 2676 | } |
| 2677 | |
| 2678 | // If the LMA region is different from the VMA region, then increment the |
| 2679 | // offset there as well. Note that we use the same "dot_value - |
| 2680 | // start_address" formula that is used in the load_address assignment below. |
| 2681 | if (lma_region != NULL && lma_region != vma_region) |
| 2682 | lma_region->increment_offset(this->get_section_name(), |
| 2683 | *dot_value - start_address, |
| 2684 | symtab, layout); |
| 2685 | |
| 2686 | // Compute the load address for the following section. |
| 2687 | if (this->output_section_ == NULL) |
| 2688 | *load_address = *dot_value; |
| 2689 | else if (this->load_address_ == NULL) |
| 2690 | { |
| 2691 | if (lma_region == NULL) |
| 2692 | *load_address = *dot_value; |
| 2693 | else |
| 2694 | *load_address = |
| 2695 | lma_region->get_current_address()->eval(symtab, layout, false); |
| 2696 | } |
| 2697 | else |
| 2698 | *load_address = (this->output_section_->load_address() |
| 2699 | + (*dot_value - start_address)); |
| 2700 | |
| 2701 | if (this->output_section_ != NULL) |
| 2702 | { |
| 2703 | if (this->is_relro_) |
| 2704 | this->output_section_->set_is_relro(); |
| 2705 | else |
| 2706 | this->output_section_->clear_is_relro(); |
| 2707 | |
| 2708 | // If this is a NOLOAD section, keep dot and load address unchanged. |
| 2709 | if (this->output_section_->is_noload()) |
| 2710 | { |
| 2711 | *dot_value = old_dot_value; |
| 2712 | *load_address = old_load_address; |
| 2713 | } |
| 2714 | } |
| 2715 | } |
| 2716 | |
| 2717 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 2718 | // this section is constrained, and the input sections do not match, |
| 2719 | // return the constraint, and set *POSD. |
| 2720 | |
| 2721 | Section_constraint |
| 2722 | Output_section_definition::check_constraint(Output_section_definition** posd) |
| 2723 | { |
| 2724 | switch (this->constraint_) |
| 2725 | { |
| 2726 | case CONSTRAINT_NONE: |
| 2727 | return CONSTRAINT_NONE; |
| 2728 | |
| 2729 | case CONSTRAINT_ONLY_IF_RO: |
| 2730 | if (this->output_section_ != NULL |
| 2731 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0) |
| 2732 | { |
| 2733 | *posd = this; |
| 2734 | return CONSTRAINT_ONLY_IF_RO; |
| 2735 | } |
| 2736 | return CONSTRAINT_NONE; |
| 2737 | |
| 2738 | case CONSTRAINT_ONLY_IF_RW: |
| 2739 | if (this->output_section_ != NULL |
| 2740 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| 2741 | { |
| 2742 | *posd = this; |
| 2743 | return CONSTRAINT_ONLY_IF_RW; |
| 2744 | } |
| 2745 | return CONSTRAINT_NONE; |
| 2746 | |
| 2747 | case CONSTRAINT_SPECIAL: |
| 2748 | if (this->output_section_ != NULL) |
| 2749 | gold_error(_("SPECIAL constraints are not implemented")); |
| 2750 | return CONSTRAINT_NONE; |
| 2751 | |
| 2752 | default: |
| 2753 | gold_unreachable(); |
| 2754 | } |
| 2755 | } |
| 2756 | |
| 2757 | // See if this is the alternate output section for a constrained |
| 2758 | // output section. If it is, transfer the Output_section and return |
| 2759 | // true. Otherwise return false. |
| 2760 | |
| 2761 | bool |
| 2762 | Output_section_definition::alternate_constraint( |
| 2763 | Output_section_definition* posd, |
| 2764 | Section_constraint constraint) |
| 2765 | { |
| 2766 | if (this->name_ != posd->name_) |
| 2767 | return false; |
| 2768 | |
| 2769 | switch (constraint) |
| 2770 | { |
| 2771 | case CONSTRAINT_ONLY_IF_RO: |
| 2772 | if (this->constraint_ != CONSTRAINT_ONLY_IF_RW) |
| 2773 | return false; |
| 2774 | break; |
| 2775 | |
| 2776 | case CONSTRAINT_ONLY_IF_RW: |
| 2777 | if (this->constraint_ != CONSTRAINT_ONLY_IF_RO) |
| 2778 | return false; |
| 2779 | break; |
| 2780 | |
| 2781 | default: |
| 2782 | gold_unreachable(); |
| 2783 | } |
| 2784 | |
| 2785 | // We have found the alternate constraint. We just need to move |
| 2786 | // over the Output_section. When constraints are used properly, |
| 2787 | // THIS should not have an output_section pointer, as all the input |
| 2788 | // sections should have matched the other definition. |
| 2789 | |
| 2790 | if (this->output_section_ != NULL) |
| 2791 | gold_error(_("mismatched definition for constrained sections")); |
| 2792 | |
| 2793 | this->output_section_ = posd->output_section_; |
| 2794 | posd->output_section_ = NULL; |
| 2795 | |
| 2796 | if (this->is_relro_) |
| 2797 | this->output_section_->set_is_relro(); |
| 2798 | else |
| 2799 | this->output_section_->clear_is_relro(); |
| 2800 | |
| 2801 | return true; |
| 2802 | } |
| 2803 | |
| 2804 | // Get the list of segments to use for an allocated section when using |
| 2805 | // a PHDRS clause. |
| 2806 | |
| 2807 | Output_section* |
| 2808 | Output_section_definition::allocate_to_segment(String_list** phdrs_list, |
| 2809 | bool* orphan) |
| 2810 | { |
| 2811 | // Update phdrs_list even if we don't have an output section. It |
| 2812 | // might be used by the following sections. |
| 2813 | if (this->phdrs_ != NULL) |
| 2814 | *phdrs_list = this->phdrs_; |
| 2815 | |
| 2816 | if (this->output_section_ == NULL) |
| 2817 | return NULL; |
| 2818 | if ((this->output_section_->flags() & elfcpp::SHF_ALLOC) == 0) |
| 2819 | return NULL; |
| 2820 | *orphan = false; |
| 2821 | return this->output_section_; |
| 2822 | } |
| 2823 | |
| 2824 | // Look for an output section by name and return the address, the load |
| 2825 | // address, the alignment, and the size. This is used when an |
| 2826 | // expression refers to an output section which was not actually |
| 2827 | // created. This returns true if the section was found, false |
| 2828 | // otherwise. |
| 2829 | |
| 2830 | bool |
| 2831 | Output_section_definition::get_output_section_info(const char* name, |
| 2832 | uint64_t* address, |
| 2833 | uint64_t* load_address, |
| 2834 | uint64_t* addralign, |
| 2835 | uint64_t* size) const |
| 2836 | { |
| 2837 | if (this->name_ != name) |
| 2838 | return false; |
| 2839 | |
| 2840 | if (this->output_section_ != NULL) |
| 2841 | { |
| 2842 | *address = this->output_section_->address(); |
| 2843 | if (this->output_section_->has_load_address()) |
| 2844 | *load_address = this->output_section_->load_address(); |
| 2845 | else |
| 2846 | *load_address = *address; |
| 2847 | *addralign = this->output_section_->addralign(); |
| 2848 | *size = this->output_section_->current_data_size(); |
| 2849 | } |
| 2850 | else |
| 2851 | { |
| 2852 | *address = this->evaluated_address_; |
| 2853 | *load_address = this->evaluated_load_address_; |
| 2854 | *addralign = this->evaluated_addralign_; |
| 2855 | *size = 0; |
| 2856 | } |
| 2857 | |
| 2858 | return true; |
| 2859 | } |
| 2860 | |
| 2861 | // Print for debugging. |
| 2862 | |
| 2863 | void |
| 2864 | Output_section_definition::print(FILE* f) const |
| 2865 | { |
| 2866 | fprintf(f, " %s ", this->name_.c_str()); |
| 2867 | |
| 2868 | if (this->address_ != NULL) |
| 2869 | { |
| 2870 | this->address_->print(f); |
| 2871 | fprintf(f, " "); |
| 2872 | } |
| 2873 | |
| 2874 | if (this->script_section_type_ != SCRIPT_SECTION_TYPE_NONE) |
| 2875 | fprintf(f, "(%s) ", |
| 2876 | this->script_section_type_name(this->script_section_type_)); |
| 2877 | |
| 2878 | fprintf(f, ": "); |
| 2879 | |
| 2880 | if (this->load_address_ != NULL) |
| 2881 | { |
| 2882 | fprintf(f, "AT("); |
| 2883 | this->load_address_->print(f); |
| 2884 | fprintf(f, ") "); |
| 2885 | } |
| 2886 | |
| 2887 | if (this->align_ != NULL) |
| 2888 | { |
| 2889 | fprintf(f, "ALIGN("); |
| 2890 | this->align_->print(f); |
| 2891 | fprintf(f, ") "); |
| 2892 | } |
| 2893 | |
| 2894 | if (this->subalign_ != NULL) |
| 2895 | { |
| 2896 | fprintf(f, "SUBALIGN("); |
| 2897 | this->subalign_->print(f); |
| 2898 | fprintf(f, ") "); |
| 2899 | } |
| 2900 | |
| 2901 | fprintf(f, "{\n"); |
| 2902 | |
| 2903 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 2904 | p != this->elements_.end(); |
| 2905 | ++p) |
| 2906 | (*p)->print(f); |
| 2907 | |
| 2908 | fprintf(f, " }"); |
| 2909 | |
| 2910 | if (this->fill_ != NULL) |
| 2911 | { |
| 2912 | fprintf(f, " = "); |
| 2913 | this->fill_->print(f); |
| 2914 | } |
| 2915 | |
| 2916 | if (this->phdrs_ != NULL) |
| 2917 | { |
| 2918 | for (String_list::const_iterator p = this->phdrs_->begin(); |
| 2919 | p != this->phdrs_->end(); |
| 2920 | ++p) |
| 2921 | fprintf(f, " :%s", p->c_str()); |
| 2922 | } |
| 2923 | |
| 2924 | fprintf(f, "\n"); |
| 2925 | } |
| 2926 | |
| 2927 | Script_sections::Section_type |
| 2928 | Output_section_definition::section_type() const |
| 2929 | { |
| 2930 | switch (this->script_section_type_) |
| 2931 | { |
| 2932 | case SCRIPT_SECTION_TYPE_NONE: |
| 2933 | return Script_sections::ST_NONE; |
| 2934 | case SCRIPT_SECTION_TYPE_NOLOAD: |
| 2935 | return Script_sections::ST_NOLOAD; |
| 2936 | case SCRIPT_SECTION_TYPE_COPY: |
| 2937 | case SCRIPT_SECTION_TYPE_DSECT: |
| 2938 | case SCRIPT_SECTION_TYPE_INFO: |
| 2939 | case SCRIPT_SECTION_TYPE_OVERLAY: |
| 2940 | // There are not really support so we treat them as ST_NONE. The |
| 2941 | // parse should have issued errors for them already. |
| 2942 | return Script_sections::ST_NONE; |
| 2943 | default: |
| 2944 | gold_unreachable(); |
| 2945 | } |
| 2946 | } |
| 2947 | |
| 2948 | // Return the name of a script section type. |
| 2949 | |
| 2950 | const char* |
| 2951 | Output_section_definition::script_section_type_name( |
| 2952 | Script_section_type script_section_type) |
| 2953 | { |
| 2954 | switch (script_section_type) |
| 2955 | { |
| 2956 | case SCRIPT_SECTION_TYPE_NONE: |
| 2957 | return "NONE"; |
| 2958 | case SCRIPT_SECTION_TYPE_NOLOAD: |
| 2959 | return "NOLOAD"; |
| 2960 | case SCRIPT_SECTION_TYPE_DSECT: |
| 2961 | return "DSECT"; |
| 2962 | case SCRIPT_SECTION_TYPE_COPY: |
| 2963 | return "COPY"; |
| 2964 | case SCRIPT_SECTION_TYPE_INFO: |
| 2965 | return "INFO"; |
| 2966 | case SCRIPT_SECTION_TYPE_OVERLAY: |
| 2967 | return "OVERLAY"; |
| 2968 | default: |
| 2969 | gold_unreachable(); |
| 2970 | } |
| 2971 | } |
| 2972 | |
| 2973 | void |
| 2974 | Output_section_definition::set_memory_region(Memory_region* mr, bool set_vma) |
| 2975 | { |
| 2976 | gold_assert(mr != NULL); |
| 2977 | // Add the current section to the specified region's list. |
| 2978 | mr->add_section(this, set_vma); |
| 2979 | } |
| 2980 | |
| 2981 | // An output section created to hold orphaned input sections. These |
| 2982 | // do not actually appear in linker scripts. However, for convenience |
| 2983 | // when setting the output section addresses, we put a marker to these |
| 2984 | // sections in the appropriate place in the list of SECTIONS elements. |
| 2985 | |
| 2986 | class Orphan_output_section : public Sections_element |
| 2987 | { |
| 2988 | public: |
| 2989 | Orphan_output_section(Output_section* os) |
| 2990 | : os_(os) |
| 2991 | { } |
| 2992 | |
| 2993 | // Return whether the orphan output section is relro. We can just |
| 2994 | // check the output section because we always set the flag, if |
| 2995 | // needed, just after we create the Orphan_output_section. |
| 2996 | bool |
| 2997 | is_relro() const |
| 2998 | { return this->os_->is_relro(); } |
| 2999 | |
| 3000 | // Initialize OSP with an output section. This should have been |
| 3001 | // done already. |
| 3002 | void |
| 3003 | orphan_section_init(Orphan_section_placement*, |
| 3004 | Script_sections::Elements_iterator) |
| 3005 | { gold_unreachable(); } |
| 3006 | |
| 3007 | // Set section addresses. |
| 3008 | void |
| 3009 | set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*, |
| 3010 | uint64_t*); |
| 3011 | |
| 3012 | // Get the list of segments to use for an allocated section when |
| 3013 | // using a PHDRS clause. |
| 3014 | Output_section* |
| 3015 | allocate_to_segment(String_list**, bool*); |
| 3016 | |
| 3017 | // Return the associated Output_section. |
| 3018 | Output_section* |
| 3019 | get_output_section() const |
| 3020 | { return this->os_; } |
| 3021 | |
| 3022 | // Print for debugging. |
| 3023 | void |
| 3024 | print(FILE* f) const |
| 3025 | { |
| 3026 | fprintf(f, " marker for orphaned output section %s\n", |
| 3027 | this->os_->name()); |
| 3028 | } |
| 3029 | |
| 3030 | private: |
| 3031 | Output_section* os_; |
| 3032 | }; |
| 3033 | |
| 3034 | // Set section addresses. |
| 3035 | |
| 3036 | void |
| 3037 | Orphan_output_section::set_section_addresses(Symbol_table*, Layout*, |
| 3038 | uint64_t* dot_value, |
| 3039 | uint64_t*, |
| 3040 | uint64_t* load_address) |
| 3041 | { |
| 3042 | typedef std::list<Output_section::Input_section> Input_section_list; |
| 3043 | |
| 3044 | bool have_load_address = *load_address != *dot_value; |
| 3045 | |
| 3046 | uint64_t address = *dot_value; |
| 3047 | address = align_address(address, this->os_->addralign()); |
| 3048 | |
| 3049 | // If input section sorting is requested via --section-ordering-file or |
| 3050 | // linker plugins, then do it here. This is important because we want |
| 3051 | // any sorting specified in the linker scripts, which will be done after |
| 3052 | // this, to take precedence. The final order of input sections is then |
| 3053 | // guaranteed to be according to the linker script specification. |
| 3054 | if (this->os_ != NULL |
| 3055 | && this->os_->input_section_order_specified()) |
| 3056 | this->os_->sort_attached_input_sections(); |
| 3057 | |
| 3058 | // For a relocatable link, all orphan sections are put at |
| 3059 | // address 0. In general we expect all sections to be at |
| 3060 | // address 0 for a relocatable link, but we permit the linker |
| 3061 | // script to override that for specific output sections. |
| 3062 | if (parameters->options().relocatable()) |
| 3063 | { |
| 3064 | address = 0; |
| 3065 | *load_address = 0; |
| 3066 | have_load_address = false; |
| 3067 | } |
| 3068 | |
| 3069 | if ((this->os_->flags() & elfcpp::SHF_ALLOC) != 0) |
| 3070 | { |
| 3071 | this->os_->set_address(address); |
| 3072 | if (have_load_address) |
| 3073 | this->os_->set_load_address(align_address(*load_address, |
| 3074 | this->os_->addralign())); |
| 3075 | } |
| 3076 | |
| 3077 | Input_section_list input_sections; |
| 3078 | address += this->os_->get_input_sections(address, "", &input_sections); |
| 3079 | |
| 3080 | for (Input_section_list::iterator p = input_sections.begin(); |
| 3081 | p != input_sections.end(); |
| 3082 | ++p) |
| 3083 | { |
| 3084 | uint64_t addralign = p->addralign(); |
| 3085 | if (!p->is_input_section()) |
| 3086 | p->output_section_data()->finalize_data_size(); |
| 3087 | uint64_t size = p->data_size(); |
| 3088 | address = align_address(address, addralign); |
| 3089 | this->os_->add_script_input_section(*p); |
| 3090 | address += size; |
| 3091 | } |
| 3092 | |
| 3093 | if (parameters->options().relocatable()) |
| 3094 | { |
| 3095 | // For a relocatable link, reset DOT_VALUE to 0. |
| 3096 | *dot_value = 0; |
| 3097 | *load_address = 0; |
| 3098 | } |
| 3099 | else if (this->os_ == NULL |
| 3100 | || (this->os_->flags() & elfcpp::SHF_TLS) == 0 |
| 3101 | || this->os_->type() != elfcpp::SHT_NOBITS) |
| 3102 | { |
| 3103 | // An SHF_TLS/SHT_NOBITS section does not take up any address space. |
| 3104 | if (!have_load_address) |
| 3105 | *load_address = address; |
| 3106 | else |
| 3107 | *load_address += address - *dot_value; |
| 3108 | |
| 3109 | *dot_value = address; |
| 3110 | } |
| 3111 | } |
| 3112 | |
| 3113 | // Get the list of segments to use for an allocated section when using |
| 3114 | // a PHDRS clause. If this is an allocated section, return the |
| 3115 | // Output_section. We don't change the list of segments. |
| 3116 | |
| 3117 | Output_section* |
| 3118 | Orphan_output_section::allocate_to_segment(String_list**, bool* orphan) |
| 3119 | { |
| 3120 | if ((this->os_->flags() & elfcpp::SHF_ALLOC) == 0) |
| 3121 | return NULL; |
| 3122 | *orphan = true; |
| 3123 | return this->os_; |
| 3124 | } |
| 3125 | |
| 3126 | // Class Phdrs_element. A program header from a PHDRS clause. |
| 3127 | |
| 3128 | class Phdrs_element |
| 3129 | { |
| 3130 | public: |
| 3131 | Phdrs_element(const char* name, size_t namelen, unsigned int type, |
| 3132 | bool includes_filehdr, bool includes_phdrs, |
| 3133 | bool is_flags_valid, unsigned int flags, |
| 3134 | Expression* load_address) |
| 3135 | : name_(name, namelen), type_(type), includes_filehdr_(includes_filehdr), |
| 3136 | includes_phdrs_(includes_phdrs), is_flags_valid_(is_flags_valid), |
| 3137 | flags_(flags), load_address_(load_address), load_address_value_(0), |
| 3138 | segment_(NULL) |
| 3139 | { } |
| 3140 | |
| 3141 | // Return the name of this segment. |
| 3142 | const std::string& |
| 3143 | name() const |
| 3144 | { return this->name_; } |
| 3145 | |
| 3146 | // Return the type of the segment. |
| 3147 | unsigned int |
| 3148 | type() const |
| 3149 | { return this->type_; } |
| 3150 | |
| 3151 | // Whether to include the file header. |
| 3152 | bool |
| 3153 | includes_filehdr() const |
| 3154 | { return this->includes_filehdr_; } |
| 3155 | |
| 3156 | // Whether to include the program headers. |
| 3157 | bool |
| 3158 | includes_phdrs() const |
| 3159 | { return this->includes_phdrs_; } |
| 3160 | |
| 3161 | // Return whether there is a load address. |
| 3162 | bool |
| 3163 | has_load_address() const |
| 3164 | { return this->load_address_ != NULL; } |
| 3165 | |
| 3166 | // Evaluate the load address expression if there is one. |
| 3167 | void |
| 3168 | eval_load_address(Symbol_table* symtab, Layout* layout) |
| 3169 | { |
| 3170 | if (this->load_address_ != NULL) |
| 3171 | this->load_address_value_ = this->load_address_->eval(symtab, layout, |
| 3172 | true); |
| 3173 | } |
| 3174 | |
| 3175 | // Return the load address. |
| 3176 | uint64_t |
| 3177 | load_address() const |
| 3178 | { |
| 3179 | gold_assert(this->load_address_ != NULL); |
| 3180 | return this->load_address_value_; |
| 3181 | } |
| 3182 | |
| 3183 | // Create the segment. |
| 3184 | Output_segment* |
| 3185 | create_segment(Layout* layout) |
| 3186 | { |
| 3187 | this->segment_ = layout->make_output_segment(this->type_, this->flags_); |
| 3188 | return this->segment_; |
| 3189 | } |
| 3190 | |
| 3191 | // Return the segment. |
| 3192 | Output_segment* |
| 3193 | segment() |
| 3194 | { return this->segment_; } |
| 3195 | |
| 3196 | // Release the segment. |
| 3197 | void |
| 3198 | release_segment() |
| 3199 | { this->segment_ = NULL; } |
| 3200 | |
| 3201 | // Set the segment flags if appropriate. |
| 3202 | void |
| 3203 | set_flags_if_valid() |
| 3204 | { |
| 3205 | if (this->is_flags_valid_) |
| 3206 | this->segment_->set_flags(this->flags_); |
| 3207 | } |
| 3208 | |
| 3209 | // Print for debugging. |
| 3210 | void |
| 3211 | print(FILE*) const; |
| 3212 | |
| 3213 | private: |
| 3214 | // The name used in the script. |
| 3215 | std::string name_; |
| 3216 | // The type of the segment (PT_LOAD, etc.). |
| 3217 | unsigned int type_; |
| 3218 | // Whether this segment includes the file header. |
| 3219 | bool includes_filehdr_; |
| 3220 | // Whether this segment includes the section headers. |
| 3221 | bool includes_phdrs_; |
| 3222 | // Whether the flags were explicitly specified. |
| 3223 | bool is_flags_valid_; |
| 3224 | // The flags for this segment (PF_R, etc.) if specified. |
| 3225 | unsigned int flags_; |
| 3226 | // The expression for the load address for this segment. This may |
| 3227 | // be NULL. |
| 3228 | Expression* load_address_; |
| 3229 | // The actual load address from evaluating the expression. |
| 3230 | uint64_t load_address_value_; |
| 3231 | // The segment itself. |
| 3232 | Output_segment* segment_; |
| 3233 | }; |
| 3234 | |
| 3235 | // Print for debugging. |
| 3236 | |
| 3237 | void |
| 3238 | Phdrs_element::print(FILE* f) const |
| 3239 | { |
| 3240 | fprintf(f, " %s 0x%x", this->name_.c_str(), this->type_); |
| 3241 | if (this->includes_filehdr_) |
| 3242 | fprintf(f, " FILEHDR"); |
| 3243 | if (this->includes_phdrs_) |
| 3244 | fprintf(f, " PHDRS"); |
| 3245 | if (this->is_flags_valid_) |
| 3246 | fprintf(f, " FLAGS(%u)", this->flags_); |
| 3247 | if (this->load_address_ != NULL) |
| 3248 | { |
| 3249 | fprintf(f, " AT("); |
| 3250 | this->load_address_->print(f); |
| 3251 | fprintf(f, ")"); |
| 3252 | } |
| 3253 | fprintf(f, ";\n"); |
| 3254 | } |
| 3255 | |
| 3256 | // Add a memory region. |
| 3257 | |
| 3258 | void |
| 3259 | Script_sections::add_memory_region(const char* name, size_t namelen, |
| 3260 | unsigned int attributes, |
| 3261 | Expression* start, Expression* length) |
| 3262 | { |
| 3263 | if (this->memory_regions_ == NULL) |
| 3264 | this->memory_regions_ = new Memory_regions(); |
| 3265 | else if (this->find_memory_region(name, namelen)) |
| 3266 | { |
| 3267 | gold_error(_("region '%.*s' already defined"), static_cast<int>(namelen), |
| 3268 | name); |
| 3269 | // FIXME: Add a GOLD extension to allow multiple regions with the same |
| 3270 | // name. This would amount to a single region covering disjoint blocks |
| 3271 | // of memory, which is useful for embedded devices. |
| 3272 | } |
| 3273 | |
| 3274 | // FIXME: Check the length and start values. Currently we allow |
| 3275 | // non-constant expressions for these values, whereas LD does not. |
| 3276 | |
| 3277 | // FIXME: Add a GOLD extension to allow NEGATIVE LENGTHS. This would |
| 3278 | // describe a region that packs from the end address going down, rather |
| 3279 | // than the start address going up. This would be useful for embedded |
| 3280 | // devices. |
| 3281 | |
| 3282 | this->memory_regions_->push_back(new Memory_region(name, namelen, attributes, |
| 3283 | start, length)); |
| 3284 | } |
| 3285 | |
| 3286 | // Find a memory region. |
| 3287 | |
| 3288 | Memory_region* |
| 3289 | Script_sections::find_memory_region(const char* name, size_t namelen) |
| 3290 | { |
| 3291 | if (this->memory_regions_ == NULL) |
| 3292 | return NULL; |
| 3293 | |
| 3294 | for (Memory_regions::const_iterator m = this->memory_regions_->begin(); |
| 3295 | m != this->memory_regions_->end(); |
| 3296 | ++m) |
| 3297 | if ((*m)->name_match(name, namelen)) |
| 3298 | return *m; |
| 3299 | |
| 3300 | return NULL; |
| 3301 | } |
| 3302 | |
| 3303 | // Find a memory region's origin. |
| 3304 | |
| 3305 | Expression* |
| 3306 | Script_sections::find_memory_region_origin(const char* name, size_t namelen) |
| 3307 | { |
| 3308 | Memory_region* mr = find_memory_region(name, namelen); |
| 3309 | if (mr == NULL) |
| 3310 | return NULL; |
| 3311 | |
| 3312 | return mr->start_address(); |
| 3313 | } |
| 3314 | |
| 3315 | // Find a memory region's length. |
| 3316 | |
| 3317 | Expression* |
| 3318 | Script_sections::find_memory_region_length(const char* name, size_t namelen) |
| 3319 | { |
| 3320 | Memory_region* mr = find_memory_region(name, namelen); |
| 3321 | if (mr == NULL) |
| 3322 | return NULL; |
| 3323 | |
| 3324 | return mr->length(); |
| 3325 | } |
| 3326 | |
| 3327 | // Set the memory region to use for the current section. |
| 3328 | |
| 3329 | void |
| 3330 | Script_sections::set_memory_region(Memory_region* mr, bool set_vma) |
| 3331 | { |
| 3332 | gold_assert(!this->sections_elements_->empty()); |
| 3333 | this->sections_elements_->back()->set_memory_region(mr, set_vma); |
| 3334 | } |
| 3335 | |
| 3336 | // Class Script_sections. |
| 3337 | |
| 3338 | Script_sections::Script_sections() |
| 3339 | : saw_sections_clause_(false), |
| 3340 | in_sections_clause_(false), |
| 3341 | sections_elements_(NULL), |
| 3342 | output_section_(NULL), |
| 3343 | memory_regions_(NULL), |
| 3344 | phdrs_elements_(NULL), |
| 3345 | orphan_section_placement_(NULL), |
| 3346 | data_segment_align_start_(), |
| 3347 | saw_data_segment_align_(false), |
| 3348 | saw_relro_end_(false), |
| 3349 | saw_segment_start_expression_(false), |
| 3350 | segments_created_(false) |
| 3351 | { |
| 3352 | } |
| 3353 | |
| 3354 | // Start a SECTIONS clause. |
| 3355 | |
| 3356 | void |
| 3357 | Script_sections::start_sections() |
| 3358 | { |
| 3359 | gold_assert(!this->in_sections_clause_ && this->output_section_ == NULL); |
| 3360 | this->saw_sections_clause_ = true; |
| 3361 | this->in_sections_clause_ = true; |
| 3362 | if (this->sections_elements_ == NULL) |
| 3363 | this->sections_elements_ = new Sections_elements; |
| 3364 | } |
| 3365 | |
| 3366 | // Finish a SECTIONS clause. |
| 3367 | |
| 3368 | void |
| 3369 | Script_sections::finish_sections() |
| 3370 | { |
| 3371 | gold_assert(this->in_sections_clause_ && this->output_section_ == NULL); |
| 3372 | this->in_sections_clause_ = false; |
| 3373 | } |
| 3374 | |
| 3375 | // Add a symbol to be defined. |
| 3376 | |
| 3377 | void |
| 3378 | Script_sections::add_symbol_assignment(const char* name, size_t length, |
| 3379 | Expression* val, bool provide, |
| 3380 | bool hidden) |
| 3381 | { |
| 3382 | if (this->output_section_ != NULL) |
| 3383 | this->output_section_->add_symbol_assignment(name, length, val, |
| 3384 | provide, hidden); |
| 3385 | else |
| 3386 | { |
| 3387 | Sections_element* p = new Sections_element_assignment(name, length, |
| 3388 | val, provide, |
| 3389 | hidden); |
| 3390 | this->sections_elements_->push_back(p); |
| 3391 | } |
| 3392 | } |
| 3393 | |
| 3394 | // Add an assignment to the special dot symbol. |
| 3395 | |
| 3396 | void |
| 3397 | Script_sections::add_dot_assignment(Expression* val) |
| 3398 | { |
| 3399 | if (this->output_section_ != NULL) |
| 3400 | this->output_section_->add_dot_assignment(val); |
| 3401 | else |
| 3402 | { |
| 3403 | // The GNU linker permits assignments to . to appears outside of |
| 3404 | // a SECTIONS clause, and treats it as appearing inside, so |
| 3405 | // sections_elements_ may be NULL here. |
| 3406 | if (this->sections_elements_ == NULL) |
| 3407 | { |
| 3408 | this->sections_elements_ = new Sections_elements; |
| 3409 | this->saw_sections_clause_ = true; |
| 3410 | } |
| 3411 | |
| 3412 | Sections_element* p = new Sections_element_dot_assignment(val); |
| 3413 | this->sections_elements_->push_back(p); |
| 3414 | } |
| 3415 | } |
| 3416 | |
| 3417 | // Add an assertion. |
| 3418 | |
| 3419 | void |
| 3420 | Script_sections::add_assertion(Expression* check, const char* message, |
| 3421 | size_t messagelen) |
| 3422 | { |
| 3423 | if (this->output_section_ != NULL) |
| 3424 | this->output_section_->add_assertion(check, message, messagelen); |
| 3425 | else |
| 3426 | { |
| 3427 | Sections_element* p = new Sections_element_assertion(check, message, |
| 3428 | messagelen); |
| 3429 | this->sections_elements_->push_back(p); |
| 3430 | } |
| 3431 | } |
| 3432 | |
| 3433 | // Start processing entries for an output section. |
| 3434 | |
| 3435 | void |
| 3436 | Script_sections::start_output_section( |
| 3437 | const char* name, |
| 3438 | size_t namelen, |
| 3439 | const Parser_output_section_header* header) |
| 3440 | { |
| 3441 | Output_section_definition* posd = new Output_section_definition(name, |
| 3442 | namelen, |
| 3443 | header); |
| 3444 | this->sections_elements_->push_back(posd); |
| 3445 | gold_assert(this->output_section_ == NULL); |
| 3446 | this->output_section_ = posd; |
| 3447 | } |
| 3448 | |
| 3449 | // Stop processing entries for an output section. |
| 3450 | |
| 3451 | void |
| 3452 | Script_sections::finish_output_section( |
| 3453 | const Parser_output_section_trailer* trailer) |
| 3454 | { |
| 3455 | gold_assert(this->output_section_ != NULL); |
| 3456 | this->output_section_->finish(trailer); |
| 3457 | this->output_section_ = NULL; |
| 3458 | } |
| 3459 | |
| 3460 | // Add a data item to the current output section. |
| 3461 | |
| 3462 | void |
| 3463 | Script_sections::add_data(int size, bool is_signed, Expression* val) |
| 3464 | { |
| 3465 | gold_assert(this->output_section_ != NULL); |
| 3466 | this->output_section_->add_data(size, is_signed, val); |
| 3467 | } |
| 3468 | |
| 3469 | // Add a fill value setting to the current output section. |
| 3470 | |
| 3471 | void |
| 3472 | Script_sections::add_fill(Expression* val) |
| 3473 | { |
| 3474 | gold_assert(this->output_section_ != NULL); |
| 3475 | this->output_section_->add_fill(val); |
| 3476 | } |
| 3477 | |
| 3478 | // Add an input section specification to the current output section. |
| 3479 | |
| 3480 | void |
| 3481 | Script_sections::add_input_section(const Input_section_spec* spec, bool keep) |
| 3482 | { |
| 3483 | gold_assert(this->output_section_ != NULL); |
| 3484 | this->output_section_->add_input_section(spec, keep); |
| 3485 | } |
| 3486 | |
| 3487 | // This is called when we see DATA_SEGMENT_ALIGN. It means that any |
| 3488 | // subsequent output sections may be relro. |
| 3489 | |
| 3490 | void |
| 3491 | Script_sections::data_segment_align() |
| 3492 | { |
| 3493 | if (this->saw_data_segment_align_) |
| 3494 | gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script")); |
| 3495 | gold_assert(!this->sections_elements_->empty()); |
| 3496 | Sections_elements::iterator p = this->sections_elements_->end(); |
| 3497 | --p; |
| 3498 | this->data_segment_align_start_ = p; |
| 3499 | this->saw_data_segment_align_ = true; |
| 3500 | } |
| 3501 | |
| 3502 | // This is called when we see DATA_SEGMENT_RELRO_END. It means that |
| 3503 | // any output sections seen since DATA_SEGMENT_ALIGN are relro. |
| 3504 | |
| 3505 | void |
| 3506 | Script_sections::data_segment_relro_end() |
| 3507 | { |
| 3508 | if (this->saw_relro_end_) |
| 3509 | gold_error(_("DATA_SEGMENT_RELRO_END may only appear once " |
| 3510 | "in a linker script")); |
| 3511 | this->saw_relro_end_ = true; |
| 3512 | |
| 3513 | if (!this->saw_data_segment_align_) |
| 3514 | gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN")); |
| 3515 | else |
| 3516 | { |
| 3517 | Sections_elements::iterator p = this->data_segment_align_start_; |
| 3518 | for (++p; p != this->sections_elements_->end(); ++p) |
| 3519 | (*p)->set_is_relro(); |
| 3520 | } |
| 3521 | } |
| 3522 | |
| 3523 | // Create any required sections. |
| 3524 | |
| 3525 | void |
| 3526 | Script_sections::create_sections(Layout* layout) |
| 3527 | { |
| 3528 | if (!this->saw_sections_clause_) |
| 3529 | return; |
| 3530 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 3531 | p != this->sections_elements_->end(); |
| 3532 | ++p) |
| 3533 | (*p)->create_sections(layout); |
| 3534 | } |
| 3535 | |
| 3536 | // Add any symbols we are defining to the symbol table. |
| 3537 | |
| 3538 | void |
| 3539 | Script_sections::add_symbols_to_table(Symbol_table* symtab) |
| 3540 | { |
| 3541 | if (!this->saw_sections_clause_) |
| 3542 | return; |
| 3543 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 3544 | p != this->sections_elements_->end(); |
| 3545 | ++p) |
| 3546 | (*p)->add_symbols_to_table(symtab); |
| 3547 | } |
| 3548 | |
| 3549 | // Finalize symbols and check assertions. |
| 3550 | |
| 3551 | void |
| 3552 | Script_sections::finalize_symbols(Symbol_table* symtab, const Layout* layout) |
| 3553 | { |
| 3554 | if (!this->saw_sections_clause_) |
| 3555 | return; |
| 3556 | uint64_t dot_value = 0; |
| 3557 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 3558 | p != this->sections_elements_->end(); |
| 3559 | ++p) |
| 3560 | (*p)->finalize_symbols(symtab, layout, &dot_value); |
| 3561 | } |
| 3562 | |
| 3563 | // Return the name of the output section to use for an input file name |
| 3564 | // and section name. |
| 3565 | |
| 3566 | const char* |
| 3567 | Script_sections::output_section_name( |
| 3568 | const char* file_name, |
| 3569 | const char* section_name, |
| 3570 | Output_section*** output_section_slot, |
| 3571 | Script_sections::Section_type* psection_type, |
| 3572 | bool* keep, |
| 3573 | bool is_input_section) |
| 3574 | { |
| 3575 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3576 | p != this->sections_elements_->end(); |
| 3577 | ++p) |
| 3578 | { |
| 3579 | const char* ret = (*p)->output_section_name(file_name, section_name, |
| 3580 | output_section_slot, |
| 3581 | psection_type, keep, |
| 3582 | is_input_section); |
| 3583 | |
| 3584 | if (ret != NULL) |
| 3585 | { |
| 3586 | // The special name /DISCARD/ means that the input section |
| 3587 | // should be discarded. |
| 3588 | if (strcmp(ret, "/DISCARD/") == 0) |
| 3589 | { |
| 3590 | *output_section_slot = NULL; |
| 3591 | *psection_type = Script_sections::ST_NONE; |
| 3592 | return NULL; |
| 3593 | } |
| 3594 | return ret; |
| 3595 | } |
| 3596 | } |
| 3597 | |
| 3598 | // We have an orphan section. |
| 3599 | *output_section_slot = NULL; |
| 3600 | *psection_type = Script_sections::ST_NONE; |
| 3601 | *keep = false; |
| 3602 | |
| 3603 | General_options::Orphan_handling orphan_handling = |
| 3604 | parameters->options().orphan_handling_enum(); |
| 3605 | if (orphan_handling == General_options::ORPHAN_DISCARD) |
| 3606 | return NULL; |
| 3607 | if (orphan_handling == General_options::ORPHAN_ERROR) |
| 3608 | { |
| 3609 | if (file_name == NULL) |
| 3610 | gold_error(_("unplaced orphan section '%s'"), section_name); |
| 3611 | else |
| 3612 | gold_error(_("unplaced orphan section '%s' from '%s'"), |
| 3613 | section_name, file_name); |
| 3614 | return NULL; |
| 3615 | } |
| 3616 | if (orphan_handling == General_options::ORPHAN_WARN) |
| 3617 | { |
| 3618 | if (file_name == NULL) |
| 3619 | gold_warning(_("orphan section '%s' is being placed in section '%s'"), |
| 3620 | section_name, section_name); |
| 3621 | else |
| 3622 | gold_warning(_("orphan section '%s' from '%s' is being placed " |
| 3623 | "in section '%s'"), |
| 3624 | section_name, file_name, section_name); |
| 3625 | } |
| 3626 | |
| 3627 | // If we couldn't find a mapping for the name, the output section |
| 3628 | // gets the name of the input section. |
| 3629 | return section_name; |
| 3630 | } |
| 3631 | |
| 3632 | // Place a marker for an orphan output section into the SECTIONS |
| 3633 | // clause. |
| 3634 | |
| 3635 | void |
| 3636 | Script_sections::place_orphan(Output_section* os) |
| 3637 | { |
| 3638 | Orphan_section_placement* osp = this->orphan_section_placement_; |
| 3639 | if (osp == NULL) |
| 3640 | { |
| 3641 | // Initialize the Orphan_section_placement structure. |
| 3642 | osp = new Orphan_section_placement(); |
| 3643 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 3644 | p != this->sections_elements_->end(); |
| 3645 | ++p) |
| 3646 | (*p)->orphan_section_init(osp, p); |
| 3647 | gold_assert(!this->sections_elements_->empty()); |
| 3648 | Sections_elements::iterator last = this->sections_elements_->end(); |
| 3649 | --last; |
| 3650 | osp->last_init(last); |
| 3651 | this->orphan_section_placement_ = osp; |
| 3652 | } |
| 3653 | |
| 3654 | Orphan_output_section* orphan = new Orphan_output_section(os); |
| 3655 | |
| 3656 | // Look for where to put ORPHAN. |
| 3657 | Sections_elements::iterator* where; |
| 3658 | if (osp->find_place(os, &where)) |
| 3659 | { |
| 3660 | if ((**where)->is_relro()) |
| 3661 | os->set_is_relro(); |
| 3662 | else |
| 3663 | os->clear_is_relro(); |
| 3664 | |
| 3665 | // We want to insert ORPHAN after *WHERE, and then update *WHERE |
| 3666 | // so that the next one goes after this one. |
| 3667 | Sections_elements::iterator p = *where; |
| 3668 | gold_assert(p != this->sections_elements_->end()); |
| 3669 | ++p; |
| 3670 | *where = this->sections_elements_->insert(p, orphan); |
| 3671 | } |
| 3672 | else |
| 3673 | { |
| 3674 | os->clear_is_relro(); |
| 3675 | // We don't have a place to put this orphan section. Put it, |
| 3676 | // and all other sections like it, at the end, but before the |
| 3677 | // sections which always come at the end. |
| 3678 | Sections_elements::iterator last = osp->last_place(); |
| 3679 | *where = this->sections_elements_->insert(last, orphan); |
| 3680 | } |
| 3681 | |
| 3682 | if ((os->flags() & elfcpp::SHF_ALLOC) != 0) |
| 3683 | osp->update_last_alloc(*where); |
| 3684 | } |
| 3685 | |
| 3686 | // Set the addresses of all the output sections. Walk through all the |
| 3687 | // elements, tracking the dot symbol. Apply assignments which set |
| 3688 | // absolute symbol values, in case they are used when setting dot. |
| 3689 | // Fill in data statement values. As we find output sections, set the |
| 3690 | // address, set the address of all associated input sections, and |
| 3691 | // update dot. Return the segment which should hold the file header |
| 3692 | // and segment headers, if any. |
| 3693 | |
| 3694 | Output_segment* |
| 3695 | Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout) |
| 3696 | { |
| 3697 | gold_assert(this->saw_sections_clause_); |
| 3698 | |
| 3699 | // Implement ONLY_IF_RO/ONLY_IF_RW constraints. These are a pain |
| 3700 | // for our representation. |
| 3701 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 3702 | p != this->sections_elements_->end(); |
| 3703 | ++p) |
| 3704 | { |
| 3705 | Output_section_definition* posd; |
| 3706 | Section_constraint failed_constraint = (*p)->check_constraint(&posd); |
| 3707 | if (failed_constraint != CONSTRAINT_NONE) |
| 3708 | { |
| 3709 | Sections_elements::iterator q; |
| 3710 | for (q = this->sections_elements_->begin(); |
| 3711 | q != this->sections_elements_->end(); |
| 3712 | ++q) |
| 3713 | { |
| 3714 | if (q != p) |
| 3715 | { |
| 3716 | if ((*q)->alternate_constraint(posd, failed_constraint)) |
| 3717 | break; |
| 3718 | } |
| 3719 | } |
| 3720 | |
| 3721 | if (q == this->sections_elements_->end()) |
| 3722 | gold_error(_("no matching section constraint")); |
| 3723 | } |
| 3724 | } |
| 3725 | |
| 3726 | // Force the alignment of the first TLS section to be the maximum |
| 3727 | // alignment of all TLS sections. |
| 3728 | Output_section* first_tls = NULL; |
| 3729 | uint64_t tls_align = 0; |
| 3730 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3731 | p != this->sections_elements_->end(); |
| 3732 | ++p) |
| 3733 | { |
| 3734 | Output_section* os = (*p)->get_output_section(); |
| 3735 | if (os != NULL && (os->flags() & elfcpp::SHF_TLS) != 0) |
| 3736 | { |
| 3737 | if (first_tls == NULL) |
| 3738 | first_tls = os; |
| 3739 | if (os->addralign() > tls_align) |
| 3740 | tls_align = os->addralign(); |
| 3741 | } |
| 3742 | } |
| 3743 | if (first_tls != NULL) |
| 3744 | first_tls->set_addralign(tls_align); |
| 3745 | |
| 3746 | // For a relocatable link, we implicitly set dot to zero. |
| 3747 | uint64_t dot_value = 0; |
| 3748 | uint64_t dot_alignment = 0; |
| 3749 | uint64_t load_address = 0; |
| 3750 | |
| 3751 | // Check to see if we want to use any of -Ttext, -Tdata and -Tbss options |
| 3752 | // to set section addresses. If the script has any SEGMENT_START |
| 3753 | // expression, we do not set the section addresses. |
| 3754 | bool use_tsection_options = |
| 3755 | (!this->saw_segment_start_expression_ |
| 3756 | && (parameters->options().user_set_Ttext() |
| 3757 | || parameters->options().user_set_Tdata() |
| 3758 | || parameters->options().user_set_Tbss())); |
| 3759 | |
| 3760 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 3761 | p != this->sections_elements_->end(); |
| 3762 | ++p) |
| 3763 | { |
| 3764 | Output_section* os = (*p)->get_output_section(); |
| 3765 | |
| 3766 | // Handle -Ttext, -Tdata and -Tbss options. We do this by looking for |
| 3767 | // the special sections by names and doing dot assignments. |
| 3768 | if (use_tsection_options |
| 3769 | && os != NULL |
| 3770 | && (os->flags() & elfcpp::SHF_ALLOC) != 0) |
| 3771 | { |
| 3772 | uint64_t new_dot_value = dot_value; |
| 3773 | |
| 3774 | if (parameters->options().user_set_Ttext() |
| 3775 | && strcmp(os->name(), ".text") == 0) |
| 3776 | new_dot_value = parameters->options().Ttext(); |
| 3777 | else if (parameters->options().user_set_Tdata() |
| 3778 | && strcmp(os->name(), ".data") == 0) |
| 3779 | new_dot_value = parameters->options().Tdata(); |
| 3780 | else if (parameters->options().user_set_Tbss() |
| 3781 | && strcmp(os->name(), ".bss") == 0) |
| 3782 | new_dot_value = parameters->options().Tbss(); |
| 3783 | |
| 3784 | // Update dot and load address if necessary. |
| 3785 | if (new_dot_value < dot_value) |
| 3786 | gold_error(_("dot may not move backward")); |
| 3787 | else if (new_dot_value != dot_value) |
| 3788 | { |
| 3789 | dot_value = new_dot_value; |
| 3790 | load_address = new_dot_value; |
| 3791 | } |
| 3792 | } |
| 3793 | |
| 3794 | (*p)->set_section_addresses(symtab, layout, &dot_value, &dot_alignment, |
| 3795 | &load_address); |
| 3796 | } |
| 3797 | |
| 3798 | if (this->phdrs_elements_ != NULL) |
| 3799 | { |
| 3800 | for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| 3801 | p != this->phdrs_elements_->end(); |
| 3802 | ++p) |
| 3803 | (*p)->eval_load_address(symtab, layout); |
| 3804 | } |
| 3805 | |
| 3806 | return this->create_segments(layout, dot_alignment); |
| 3807 | } |
| 3808 | |
| 3809 | // Sort the sections in order to put them into segments. |
| 3810 | |
| 3811 | class Sort_output_sections |
| 3812 | { |
| 3813 | public: |
| 3814 | Sort_output_sections(const Script_sections::Sections_elements* elements) |
| 3815 | : elements_(elements) |
| 3816 | { } |
| 3817 | |
| 3818 | bool |
| 3819 | operator()(const Output_section* os1, const Output_section* os2) const; |
| 3820 | |
| 3821 | private: |
| 3822 | int |
| 3823 | script_compare(const Output_section* os1, const Output_section* os2) const; |
| 3824 | |
| 3825 | private: |
| 3826 | const Script_sections::Sections_elements* elements_; |
| 3827 | }; |
| 3828 | |
| 3829 | bool |
| 3830 | Sort_output_sections::operator()(const Output_section* os1, |
| 3831 | const Output_section* os2) const |
| 3832 | { |
| 3833 | // Sort first by the load address. |
| 3834 | uint64_t lma1 = (os1->has_load_address() |
| 3835 | ? os1->load_address() |
| 3836 | : os1->address()); |
| 3837 | uint64_t lma2 = (os2->has_load_address() |
| 3838 | ? os2->load_address() |
| 3839 | : os2->address()); |
| 3840 | if (lma1 != lma2) |
| 3841 | return lma1 < lma2; |
| 3842 | |
| 3843 | // Then sort by the virtual address. |
| 3844 | if (os1->address() != os2->address()) |
| 3845 | return os1->address() < os2->address(); |
| 3846 | |
| 3847 | // If the linker script says which of these sections is first, go |
| 3848 | // with what it says. |
| 3849 | int i = this->script_compare(os1, os2); |
| 3850 | if (i != 0) |
| 3851 | return i < 0; |
| 3852 | |
| 3853 | // Sort PROGBITS before NOBITS. |
| 3854 | bool nobits1 = os1->type() == elfcpp::SHT_NOBITS; |
| 3855 | bool nobits2 = os2->type() == elfcpp::SHT_NOBITS; |
| 3856 | if (nobits1 != nobits2) |
| 3857 | return nobits2; |
| 3858 | |
| 3859 | // Sort PROGBITS TLS sections to the end, NOBITS TLS sections to the |
| 3860 | // beginning. |
| 3861 | bool tls1 = (os1->flags() & elfcpp::SHF_TLS) != 0; |
| 3862 | bool tls2 = (os2->flags() & elfcpp::SHF_TLS) != 0; |
| 3863 | if (tls1 != tls2) |
| 3864 | return nobits1 ? tls1 : tls2; |
| 3865 | |
| 3866 | // Sort non-NOLOAD before NOLOAD. |
| 3867 | if (os1->is_noload() && !os2->is_noload()) |
| 3868 | return true; |
| 3869 | if (!os1->is_noload() && os2->is_noload()) |
| 3870 | return true; |
| 3871 | |
| 3872 | // The sections seem practically identical. Sort by name to get a |
| 3873 | // stable sort. |
| 3874 | return os1->name() < os2->name(); |
| 3875 | } |
| 3876 | |
| 3877 | // Return -1 if OS1 comes before OS2 in ELEMENTS_, 1 if comes after, 0 |
| 3878 | // if either OS1 or OS2 is not mentioned. This ensures that we keep |
| 3879 | // empty sections in the order in which they appear in a linker |
| 3880 | // script. |
| 3881 | |
| 3882 | int |
| 3883 | Sort_output_sections::script_compare(const Output_section* os1, |
| 3884 | const Output_section* os2) const |
| 3885 | { |
| 3886 | if (this->elements_ == NULL) |
| 3887 | return 0; |
| 3888 | |
| 3889 | bool found_os1 = false; |
| 3890 | bool found_os2 = false; |
| 3891 | for (Script_sections::Sections_elements::const_iterator |
| 3892 | p = this->elements_->begin(); |
| 3893 | p != this->elements_->end(); |
| 3894 | ++p) |
| 3895 | { |
| 3896 | if (os2 == (*p)->get_output_section()) |
| 3897 | { |
| 3898 | if (found_os1) |
| 3899 | return -1; |
| 3900 | found_os2 = true; |
| 3901 | } |
| 3902 | else if (os1 == (*p)->get_output_section()) |
| 3903 | { |
| 3904 | if (found_os2) |
| 3905 | return 1; |
| 3906 | found_os1 = true; |
| 3907 | } |
| 3908 | } |
| 3909 | |
| 3910 | return 0; |
| 3911 | } |
| 3912 | |
| 3913 | // Return whether OS is a BSS section. This is a SHT_NOBITS section. |
| 3914 | // We treat a section with the SHF_TLS flag set as taking up space |
| 3915 | // even if it is SHT_NOBITS (this is true of .tbss), as we allocate |
| 3916 | // space for them in the file. |
| 3917 | |
| 3918 | bool |
| 3919 | Script_sections::is_bss_section(const Output_section* os) |
| 3920 | { |
| 3921 | return (os->type() == elfcpp::SHT_NOBITS |
| 3922 | && (os->flags() & elfcpp::SHF_TLS) == 0); |
| 3923 | } |
| 3924 | |
| 3925 | // Return the size taken by the file header and the program headers. |
| 3926 | |
| 3927 | size_t |
| 3928 | Script_sections::total_header_size(Layout* layout) const |
| 3929 | { |
| 3930 | size_t segment_count = layout->segment_count(); |
| 3931 | size_t file_header_size; |
| 3932 | size_t segment_headers_size; |
| 3933 | if (parameters->target().get_size() == 32) |
| 3934 | { |
| 3935 | file_header_size = elfcpp::Elf_sizes<32>::ehdr_size; |
| 3936 | segment_headers_size = segment_count * elfcpp::Elf_sizes<32>::phdr_size; |
| 3937 | } |
| 3938 | else if (parameters->target().get_size() == 64) |
| 3939 | { |
| 3940 | file_header_size = elfcpp::Elf_sizes<64>::ehdr_size; |
| 3941 | segment_headers_size = segment_count * elfcpp::Elf_sizes<64>::phdr_size; |
| 3942 | } |
| 3943 | else |
| 3944 | gold_unreachable(); |
| 3945 | |
| 3946 | return file_header_size + segment_headers_size; |
| 3947 | } |
| 3948 | |
| 3949 | // Return the amount we have to subtract from the LMA to accommodate |
| 3950 | // headers of the given size. The complication is that the file |
| 3951 | // header have to be at the start of a page, as otherwise it will not |
| 3952 | // be at the start of the file. |
| 3953 | |
| 3954 | uint64_t |
| 3955 | Script_sections::header_size_adjustment(uint64_t lma, |
| 3956 | size_t sizeof_headers) const |
| 3957 | { |
| 3958 | const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| 3959 | uint64_t hdr_lma = lma - sizeof_headers; |
| 3960 | hdr_lma &= ~(abi_pagesize - 1); |
| 3961 | return lma - hdr_lma; |
| 3962 | } |
| 3963 | |
| 3964 | // Create the PT_LOAD segments when using a SECTIONS clause. Returns |
| 3965 | // the segment which should hold the file header and segment headers, |
| 3966 | // if any. |
| 3967 | |
| 3968 | Output_segment* |
| 3969 | Script_sections::create_segments(Layout* layout, uint64_t dot_alignment) |
| 3970 | { |
| 3971 | gold_assert(this->saw_sections_clause_); |
| 3972 | |
| 3973 | if (parameters->options().relocatable()) |
| 3974 | return NULL; |
| 3975 | |
| 3976 | if (this->saw_phdrs_clause()) |
| 3977 | return create_segments_from_phdrs_clause(layout, dot_alignment); |
| 3978 | |
| 3979 | Layout::Section_list sections; |
| 3980 | layout->get_allocated_sections(§ions); |
| 3981 | |
| 3982 | // Sort the sections by address. |
| 3983 | std::stable_sort(sections.begin(), sections.end(), |
| 3984 | Sort_output_sections(this->sections_elements_)); |
| 3985 | |
| 3986 | this->create_note_and_tls_segments(layout, §ions); |
| 3987 | |
| 3988 | // Walk through the sections adding them to PT_LOAD segments. |
| 3989 | const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| 3990 | Output_segment* first_seg = NULL; |
| 3991 | Output_segment* current_seg = NULL; |
| 3992 | bool is_current_seg_readonly = true; |
| 3993 | uint64_t last_vma = 0; |
| 3994 | uint64_t last_lma = 0; |
| 3995 | uint64_t last_size = 0; |
| 3996 | bool in_bss = false; |
| 3997 | for (Layout::Section_list::iterator p = sections.begin(); |
| 3998 | p != sections.end(); |
| 3999 | ++p) |
| 4000 | { |
| 4001 | const uint64_t vma = (*p)->address(); |
| 4002 | const uint64_t lma = ((*p)->has_load_address() |
| 4003 | ? (*p)->load_address() |
| 4004 | : vma); |
| 4005 | const uint64_t size = (*p)->current_data_size(); |
| 4006 | |
| 4007 | bool need_new_segment; |
| 4008 | if (current_seg == NULL) |
| 4009 | need_new_segment = true; |
| 4010 | else if (lma - vma != last_lma - last_vma) |
| 4011 | { |
| 4012 | // This section has a different LMA relationship than the |
| 4013 | // last one; we need a new segment. |
| 4014 | need_new_segment = true; |
| 4015 | } |
| 4016 | else if (align_address(last_lma + last_size, abi_pagesize) |
| 4017 | < align_address(lma, abi_pagesize)) |
| 4018 | { |
| 4019 | // Putting this section in the segment would require |
| 4020 | // skipping a page. |
| 4021 | need_new_segment = true; |
| 4022 | } |
| 4023 | else if (in_bss && !is_bss_section(*p)) |
| 4024 | { |
| 4025 | // A non-BSS section can not follow a BSS section in the |
| 4026 | // same segment. |
| 4027 | need_new_segment = true; |
| 4028 | } |
| 4029 | else if (is_current_seg_readonly |
| 4030 | && ((*p)->flags() & elfcpp::SHF_WRITE) != 0 |
| 4031 | && !parameters->options().omagic()) |
| 4032 | { |
| 4033 | // Don't put a writable section in the same segment as a |
| 4034 | // non-writable section. |
| 4035 | need_new_segment = true; |
| 4036 | } |
| 4037 | else |
| 4038 | { |
| 4039 | // Otherwise, reuse the existing segment. |
| 4040 | need_new_segment = false; |
| 4041 | } |
| 4042 | |
| 4043 | elfcpp::Elf_Word seg_flags = |
| 4044 | Layout::section_flags_to_segment((*p)->flags()); |
| 4045 | |
| 4046 | if (need_new_segment) |
| 4047 | { |
| 4048 | current_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| 4049 | seg_flags); |
| 4050 | current_seg->set_addresses(vma, lma); |
| 4051 | current_seg->set_minimum_p_align(dot_alignment); |
| 4052 | if (first_seg == NULL) |
| 4053 | first_seg = current_seg; |
| 4054 | is_current_seg_readonly = true; |
| 4055 | in_bss = false; |
| 4056 | } |
| 4057 | |
| 4058 | current_seg->add_output_section_to_load(layout, *p, seg_flags); |
| 4059 | |
| 4060 | if (((*p)->flags() & elfcpp::SHF_WRITE) != 0) |
| 4061 | is_current_seg_readonly = false; |
| 4062 | |
| 4063 | if (is_bss_section(*p) && size > 0) |
| 4064 | in_bss = true; |
| 4065 | |
| 4066 | last_vma = vma; |
| 4067 | last_lma = lma; |
| 4068 | last_size = size; |
| 4069 | } |
| 4070 | |
| 4071 | // An ELF program should work even if the program headers are not in |
| 4072 | // a PT_LOAD segment. However, it appears that the Linux kernel |
| 4073 | // does not set the AT_PHDR auxiliary entry in that case. It sets |
| 4074 | // the load address to p_vaddr - p_offset of the first PT_LOAD |
| 4075 | // segment. It then sets AT_PHDR to the load address plus the |
| 4076 | // offset to the program headers, e_phoff in the file header. This |
| 4077 | // fails when the program headers appear in the file before the |
| 4078 | // first PT_LOAD segment. Therefore, we always create a PT_LOAD |
| 4079 | // segment to hold the file header and the program headers. This is |
| 4080 | // effectively what the GNU linker does, and it is slightly more |
| 4081 | // efficient in any case. We try to use the first PT_LOAD segment |
| 4082 | // if we can, otherwise we make a new one. |
| 4083 | |
| 4084 | if (first_seg == NULL) |
| 4085 | return NULL; |
| 4086 | |
| 4087 | // -n or -N mean that the program is not demand paged and there is |
| 4088 | // no need to put the program headers in a PT_LOAD segment. |
| 4089 | if (parameters->options().nmagic() || parameters->options().omagic()) |
| 4090 | return NULL; |
| 4091 | |
| 4092 | size_t sizeof_headers = this->total_header_size(layout); |
| 4093 | |
| 4094 | uint64_t vma = first_seg->vaddr(); |
| 4095 | uint64_t lma = first_seg->paddr(); |
| 4096 | |
| 4097 | uint64_t subtract = this->header_size_adjustment(lma, sizeof_headers); |
| 4098 | |
| 4099 | if ((lma & (abi_pagesize - 1)) >= sizeof_headers) |
| 4100 | { |
| 4101 | first_seg->set_addresses(vma - subtract, lma - subtract); |
| 4102 | return first_seg; |
| 4103 | } |
| 4104 | |
| 4105 | // If there is no room to squeeze in the headers, then punt. The |
| 4106 | // resulting executable probably won't run on GNU/Linux, but we |
| 4107 | // trust that the user knows what they are doing. |
| 4108 | if (lma < subtract || vma < subtract) |
| 4109 | return NULL; |
| 4110 | |
| 4111 | // If memory regions have been specified and the address range |
| 4112 | // we are about to use is not contained within any region then |
| 4113 | // issue a warning message about the segment we are going to |
| 4114 | // create. It will be outside of any region and so possibly |
| 4115 | // using non-existent or protected memory. We test LMA rather |
| 4116 | // than VMA since we assume that the headers will never be |
| 4117 | // relocated. |
| 4118 | if (this->memory_regions_ != NULL |
| 4119 | && !this->block_in_region (NULL, layout, lma - subtract, subtract)) |
| 4120 | gold_warning(_("creating a segment to contain the file and program" |
| 4121 | " headers outside of any MEMORY region")); |
| 4122 | |
| 4123 | Output_segment* load_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| 4124 | elfcpp::PF_R); |
| 4125 | load_seg->set_addresses(vma - subtract, lma - subtract); |
| 4126 | |
| 4127 | return load_seg; |
| 4128 | } |
| 4129 | |
| 4130 | // Create a PT_NOTE segment for each SHT_NOTE section and a PT_TLS |
| 4131 | // segment if there are any SHT_TLS sections. |
| 4132 | |
| 4133 | void |
| 4134 | Script_sections::create_note_and_tls_segments( |
| 4135 | Layout* layout, |
| 4136 | const Layout::Section_list* sections) |
| 4137 | { |
| 4138 | gold_assert(!this->saw_phdrs_clause()); |
| 4139 | |
| 4140 | bool saw_tls = false; |
| 4141 | for (Layout::Section_list::const_iterator p = sections->begin(); |
| 4142 | p != sections->end(); |
| 4143 | ++p) |
| 4144 | { |
| 4145 | if ((*p)->type() == elfcpp::SHT_NOTE) |
| 4146 | { |
| 4147 | elfcpp::Elf_Word seg_flags = |
| 4148 | Layout::section_flags_to_segment((*p)->flags()); |
| 4149 | Output_segment* oseg = layout->make_output_segment(elfcpp::PT_NOTE, |
| 4150 | seg_flags); |
| 4151 | oseg->add_output_section_to_nonload(*p, seg_flags); |
| 4152 | |
| 4153 | // Incorporate any subsequent SHT_NOTE sections, in the |
| 4154 | // hopes that the script is sensible. |
| 4155 | Layout::Section_list::const_iterator pnext = p + 1; |
| 4156 | while (pnext != sections->end() |
| 4157 | && (*pnext)->type() == elfcpp::SHT_NOTE) |
| 4158 | { |
| 4159 | seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| 4160 | oseg->add_output_section_to_nonload(*pnext, seg_flags); |
| 4161 | p = pnext; |
| 4162 | ++pnext; |
| 4163 | } |
| 4164 | } |
| 4165 | |
| 4166 | if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| 4167 | { |
| 4168 | if (saw_tls) |
| 4169 | gold_error(_("TLS sections are not adjacent")); |
| 4170 | |
| 4171 | elfcpp::Elf_Word seg_flags = |
| 4172 | Layout::section_flags_to_segment((*p)->flags()); |
| 4173 | Output_segment* oseg = layout->make_output_segment(elfcpp::PT_TLS, |
| 4174 | seg_flags); |
| 4175 | oseg->add_output_section_to_nonload(*p, seg_flags); |
| 4176 | |
| 4177 | Layout::Section_list::const_iterator pnext = p + 1; |
| 4178 | while (pnext != sections->end() |
| 4179 | && ((*pnext)->flags() & elfcpp::SHF_TLS) != 0) |
| 4180 | { |
| 4181 | seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| 4182 | oseg->add_output_section_to_nonload(*pnext, seg_flags); |
| 4183 | p = pnext; |
| 4184 | ++pnext; |
| 4185 | } |
| 4186 | |
| 4187 | saw_tls = true; |
| 4188 | } |
| 4189 | |
| 4190 | // If we see a section named .interp then put the .interp section |
| 4191 | // in a PT_INTERP segment. |
| 4192 | // This is for GNU ld compatibility. |
| 4193 | if (strcmp((*p)->name(), ".interp") == 0) |
| 4194 | { |
| 4195 | elfcpp::Elf_Word seg_flags = |
| 4196 | Layout::section_flags_to_segment((*p)->flags()); |
| 4197 | Output_segment* oseg = layout->make_output_segment(elfcpp::PT_INTERP, |
| 4198 | seg_flags); |
| 4199 | oseg->add_output_section_to_nonload(*p, seg_flags); |
| 4200 | } |
| 4201 | } |
| 4202 | |
| 4203 | this->segments_created_ = true; |
| 4204 | } |
| 4205 | |
| 4206 | // Add a program header. The PHDRS clause is syntactically distinct |
| 4207 | // from the SECTIONS clause, but we implement it with the SECTIONS |
| 4208 | // support because PHDRS is useless if there is no SECTIONS clause. |
| 4209 | |
| 4210 | void |
| 4211 | Script_sections::add_phdr(const char* name, size_t namelen, unsigned int type, |
| 4212 | bool includes_filehdr, bool includes_phdrs, |
| 4213 | bool is_flags_valid, unsigned int flags, |
| 4214 | Expression* load_address) |
| 4215 | { |
| 4216 | if (this->phdrs_elements_ == NULL) |
| 4217 | this->phdrs_elements_ = new Phdrs_elements(); |
| 4218 | this->phdrs_elements_->push_back(new Phdrs_element(name, namelen, type, |
| 4219 | includes_filehdr, |
| 4220 | includes_phdrs, |
| 4221 | is_flags_valid, flags, |
| 4222 | load_address)); |
| 4223 | } |
| 4224 | |
| 4225 | // Return the number of segments we expect to create based on the |
| 4226 | // SECTIONS clause. This is used to implement SIZEOF_HEADERS. |
| 4227 | |
| 4228 | size_t |
| 4229 | Script_sections::expected_segment_count(const Layout* layout) const |
| 4230 | { |
| 4231 | // If we've already created the segments, we won't be adding any more. |
| 4232 | if (this->segments_created_) |
| 4233 | return 0; |
| 4234 | |
| 4235 | if (this->saw_phdrs_clause()) |
| 4236 | return this->phdrs_elements_->size(); |
| 4237 | |
| 4238 | Layout::Section_list sections; |
| 4239 | layout->get_allocated_sections(§ions); |
| 4240 | |
| 4241 | // We assume that we will need two PT_LOAD segments. |
| 4242 | size_t ret = 2; |
| 4243 | |
| 4244 | bool saw_note = false; |
| 4245 | bool saw_tls = false; |
| 4246 | bool saw_interp = false; |
| 4247 | for (Layout::Section_list::const_iterator p = sections.begin(); |
| 4248 | p != sections.end(); |
| 4249 | ++p) |
| 4250 | { |
| 4251 | if ((*p)->type() == elfcpp::SHT_NOTE) |
| 4252 | { |
| 4253 | // Assume that all note sections will fit into a single |
| 4254 | // PT_NOTE segment. |
| 4255 | if (!saw_note) |
| 4256 | { |
| 4257 | ++ret; |
| 4258 | saw_note = true; |
| 4259 | } |
| 4260 | } |
| 4261 | else if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| 4262 | { |
| 4263 | // There can only be one PT_TLS segment. |
| 4264 | if (!saw_tls) |
| 4265 | { |
| 4266 | ++ret; |
| 4267 | saw_tls = true; |
| 4268 | } |
| 4269 | } |
| 4270 | else if (strcmp((*p)->name(), ".interp") == 0) |
| 4271 | { |
| 4272 | // There can only be one PT_INTERP segment. |
| 4273 | if (!saw_interp) |
| 4274 | { |
| 4275 | ++ret; |
| 4276 | saw_interp = true; |
| 4277 | } |
| 4278 | } |
| 4279 | } |
| 4280 | |
| 4281 | return ret; |
| 4282 | } |
| 4283 | |
| 4284 | // Create the segments from a PHDRS clause. Return the segment which |
| 4285 | // should hold the file header and program headers, if any. |
| 4286 | |
| 4287 | Output_segment* |
| 4288 | Script_sections::create_segments_from_phdrs_clause(Layout* layout, |
| 4289 | uint64_t dot_alignment) |
| 4290 | { |
| 4291 | this->attach_sections_using_phdrs_clause(layout); |
| 4292 | return this->set_phdrs_clause_addresses(layout, dot_alignment); |
| 4293 | } |
| 4294 | |
| 4295 | // Create the segments from the PHDRS clause, and put the output |
| 4296 | // sections in them. |
| 4297 | |
| 4298 | void |
| 4299 | Script_sections::attach_sections_using_phdrs_clause(Layout* layout) |
| 4300 | { |
| 4301 | typedef std::map<std::string, Output_segment*> Name_to_segment; |
| 4302 | Name_to_segment name_to_segment; |
| 4303 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 4304 | p != this->phdrs_elements_->end(); |
| 4305 | ++p) |
| 4306 | name_to_segment[(*p)->name()] = (*p)->create_segment(layout); |
| 4307 | this->segments_created_ = true; |
| 4308 | |
| 4309 | // Walk through the output sections and attach them to segments. |
| 4310 | // Output sections in the script which do not list segments are |
| 4311 | // attached to the same set of segments as the immediately preceding |
| 4312 | // output section. |
| 4313 | |
| 4314 | String_list* phdr_names = NULL; |
| 4315 | bool load_segments_only = false; |
| 4316 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 4317 | p != this->sections_elements_->end(); |
| 4318 | ++p) |
| 4319 | { |
| 4320 | bool is_orphan; |
| 4321 | String_list* old_phdr_names = phdr_names; |
| 4322 | Output_section* os = (*p)->allocate_to_segment(&phdr_names, &is_orphan); |
| 4323 | if (os == NULL) |
| 4324 | continue; |
| 4325 | |
| 4326 | elfcpp::Elf_Word seg_flags = |
| 4327 | Layout::section_flags_to_segment(os->flags()); |
| 4328 | |
| 4329 | if (phdr_names == NULL) |
| 4330 | { |
| 4331 | // Don't worry about empty orphan sections. |
| 4332 | if (is_orphan && os->current_data_size() > 0) |
| 4333 | gold_error(_("allocated section %s not in any segment"), |
| 4334 | os->name()); |
| 4335 | |
| 4336 | // To avoid later crashes drop this section into the first |
| 4337 | // PT_LOAD segment. |
| 4338 | for (Phdrs_elements::const_iterator ppe = |
| 4339 | this->phdrs_elements_->begin(); |
| 4340 | ppe != this->phdrs_elements_->end(); |
| 4341 | ++ppe) |
| 4342 | { |
| 4343 | Output_segment* oseg = (*ppe)->segment(); |
| 4344 | if (oseg->type() == elfcpp::PT_LOAD) |
| 4345 | { |
| 4346 | oseg->add_output_section_to_load(layout, os, seg_flags); |
| 4347 | break; |
| 4348 | } |
| 4349 | } |
| 4350 | |
| 4351 | continue; |
| 4352 | } |
| 4353 | |
| 4354 | // We see a list of segments names. Disable PT_LOAD segment only |
| 4355 | // filtering. |
| 4356 | if (old_phdr_names != phdr_names) |
| 4357 | load_segments_only = false; |
| 4358 | |
| 4359 | // If this is an orphan section--one that was not explicitly |
| 4360 | // mentioned in the linker script--then it should not inherit |
| 4361 | // any segment type other than PT_LOAD. Otherwise, e.g., the |
| 4362 | // PT_INTERP segment will pick up following orphan sections, |
| 4363 | // which does not make sense. If this is not an orphan section, |
| 4364 | // we trust the linker script. |
| 4365 | if (is_orphan) |
| 4366 | { |
| 4367 | // Enable PT_LOAD segments only filtering until we see another |
| 4368 | // list of segment names. |
| 4369 | load_segments_only = true; |
| 4370 | } |
| 4371 | |
| 4372 | bool in_load_segment = false; |
| 4373 | for (String_list::const_iterator q = phdr_names->begin(); |
| 4374 | q != phdr_names->end(); |
| 4375 | ++q) |
| 4376 | { |
| 4377 | Name_to_segment::const_iterator r = name_to_segment.find(*q); |
| 4378 | if (r == name_to_segment.end()) |
| 4379 | gold_error(_("no segment %s"), q->c_str()); |
| 4380 | else |
| 4381 | { |
| 4382 | if (load_segments_only |
| 4383 | && r->second->type() != elfcpp::PT_LOAD) |
| 4384 | continue; |
| 4385 | |
| 4386 | if (r->second->type() != elfcpp::PT_LOAD) |
| 4387 | r->second->add_output_section_to_nonload(os, seg_flags); |
| 4388 | else |
| 4389 | { |
| 4390 | r->second->add_output_section_to_load(layout, os, seg_flags); |
| 4391 | if (in_load_segment) |
| 4392 | gold_error(_("section in two PT_LOAD segments")); |
| 4393 | in_load_segment = true; |
| 4394 | } |
| 4395 | } |
| 4396 | } |
| 4397 | |
| 4398 | if (!in_load_segment) |
| 4399 | gold_error(_("allocated section not in any PT_LOAD segment")); |
| 4400 | } |
| 4401 | } |
| 4402 | |
| 4403 | // Set the addresses for segments created from a PHDRS clause. Return |
| 4404 | // the segment which should hold the file header and program headers, |
| 4405 | // if any. |
| 4406 | |
| 4407 | Output_segment* |
| 4408 | Script_sections::set_phdrs_clause_addresses(Layout* layout, |
| 4409 | uint64_t dot_alignment) |
| 4410 | { |
| 4411 | Output_segment* load_seg = NULL; |
| 4412 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 4413 | p != this->phdrs_elements_->end(); |
| 4414 | ++p) |
| 4415 | { |
| 4416 | // Note that we have to set the flags after adding the output |
| 4417 | // sections to the segment, as adding an output segment can |
| 4418 | // change the flags. |
| 4419 | (*p)->set_flags_if_valid(); |
| 4420 | |
| 4421 | Output_segment* oseg = (*p)->segment(); |
| 4422 | |
| 4423 | if (oseg->type() != elfcpp::PT_LOAD) |
| 4424 | { |
| 4425 | // The addresses of non-PT_LOAD segments are set from the |
| 4426 | // PT_LOAD segments. |
| 4427 | if ((*p)->has_load_address()) |
| 4428 | gold_error(_("may only specify load address for PT_LOAD segment")); |
| 4429 | continue; |
| 4430 | } |
| 4431 | |
| 4432 | oseg->set_minimum_p_align(dot_alignment); |
| 4433 | |
| 4434 | // The output sections should have addresses from the SECTIONS |
| 4435 | // clause. The addresses don't have to be in order, so find the |
| 4436 | // one with the lowest load address. Use that to set the |
| 4437 | // address of the segment. |
| 4438 | |
| 4439 | Output_section* osec = oseg->section_with_lowest_load_address(); |
| 4440 | if (osec == NULL) |
| 4441 | { |
| 4442 | oseg->set_addresses(0, 0); |
| 4443 | continue; |
| 4444 | } |
| 4445 | |
| 4446 | uint64_t vma = osec->address(); |
| 4447 | uint64_t lma = osec->has_load_address() ? osec->load_address() : vma; |
| 4448 | |
| 4449 | // Override the load address of the section with the load |
| 4450 | // address specified for the segment. |
| 4451 | if ((*p)->has_load_address()) |
| 4452 | { |
| 4453 | if (osec->has_load_address()) |
| 4454 | gold_warning(_("PHDRS load address overrides " |
| 4455 | "section %s load address"), |
| 4456 | osec->name()); |
| 4457 | |
| 4458 | lma = (*p)->load_address(); |
| 4459 | } |
| 4460 | |
| 4461 | bool headers = (*p)->includes_filehdr() && (*p)->includes_phdrs(); |
| 4462 | if (!headers && ((*p)->includes_filehdr() || (*p)->includes_phdrs())) |
| 4463 | { |
| 4464 | // We could support this if we wanted to. |
| 4465 | gold_error(_("using only one of FILEHDR and PHDRS is " |
| 4466 | "not currently supported")); |
| 4467 | } |
| 4468 | if (headers) |
| 4469 | { |
| 4470 | size_t sizeof_headers = this->total_header_size(layout); |
| 4471 | uint64_t subtract = this->header_size_adjustment(lma, |
| 4472 | sizeof_headers); |
| 4473 | if (lma >= subtract && vma >= subtract) |
| 4474 | { |
| 4475 | lma -= subtract; |
| 4476 | vma -= subtract; |
| 4477 | } |
| 4478 | else |
| 4479 | { |
| 4480 | gold_error(_("sections loaded on first page without room " |
| 4481 | "for file and program headers " |
| 4482 | "are not supported")); |
| 4483 | } |
| 4484 | |
| 4485 | if (load_seg != NULL) |
| 4486 | gold_error(_("using FILEHDR and PHDRS on more than one " |
| 4487 | "PT_LOAD segment is not currently supported")); |
| 4488 | load_seg = oseg; |
| 4489 | } |
| 4490 | |
| 4491 | oseg->set_addresses(vma, lma); |
| 4492 | } |
| 4493 | |
| 4494 | return load_seg; |
| 4495 | } |
| 4496 | |
| 4497 | // Add the file header and segment headers to non-load segments |
| 4498 | // specified in the PHDRS clause. |
| 4499 | |
| 4500 | void |
| 4501 | Script_sections::put_headers_in_phdrs(Output_data* file_header, |
| 4502 | Output_data* segment_headers) |
| 4503 | { |
| 4504 | gold_assert(this->saw_phdrs_clause()); |
| 4505 | for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| 4506 | p != this->phdrs_elements_->end(); |
| 4507 | ++p) |
| 4508 | { |
| 4509 | if ((*p)->type() != elfcpp::PT_LOAD) |
| 4510 | { |
| 4511 | if ((*p)->includes_phdrs()) |
| 4512 | (*p)->segment()->add_initial_output_data(segment_headers); |
| 4513 | if ((*p)->includes_filehdr()) |
| 4514 | (*p)->segment()->add_initial_output_data(file_header); |
| 4515 | } |
| 4516 | } |
| 4517 | } |
| 4518 | |
| 4519 | // Look for an output section by name and return the address, the load |
| 4520 | // address, the alignment, and the size. This is used when an |
| 4521 | // expression refers to an output section which was not actually |
| 4522 | // created. This returns true if the section was found, false |
| 4523 | // otherwise. |
| 4524 | |
| 4525 | bool |
| 4526 | Script_sections::get_output_section_info(const char* name, uint64_t* address, |
| 4527 | uint64_t* load_address, |
| 4528 | uint64_t* addralign, |
| 4529 | uint64_t* size) const |
| 4530 | { |
| 4531 | if (!this->saw_sections_clause_) |
| 4532 | return false; |
| 4533 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 4534 | p != this->sections_elements_->end(); |
| 4535 | ++p) |
| 4536 | if ((*p)->get_output_section_info(name, address, load_address, addralign, |
| 4537 | size)) |
| 4538 | return true; |
| 4539 | return false; |
| 4540 | } |
| 4541 | |
| 4542 | // Release all Output_segments. This remove all pointers to all |
| 4543 | // Output_segments. |
| 4544 | |
| 4545 | void |
| 4546 | Script_sections::release_segments() |
| 4547 | { |
| 4548 | if (this->saw_phdrs_clause()) |
| 4549 | { |
| 4550 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 4551 | p != this->phdrs_elements_->end(); |
| 4552 | ++p) |
| 4553 | (*p)->release_segment(); |
| 4554 | } |
| 4555 | this->segments_created_ = false; |
| 4556 | } |
| 4557 | |
| 4558 | // Print the SECTIONS clause to F for debugging. |
| 4559 | |
| 4560 | void |
| 4561 | Script_sections::print(FILE* f) const |
| 4562 | { |
| 4563 | if (this->phdrs_elements_ != NULL) |
| 4564 | { |
| 4565 | fprintf(f, "PHDRS {\n"); |
| 4566 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 4567 | p != this->phdrs_elements_->end(); |
| 4568 | ++p) |
| 4569 | (*p)->print(f); |
| 4570 | fprintf(f, "}\n"); |
| 4571 | } |
| 4572 | |
| 4573 | if (this->memory_regions_ != NULL) |
| 4574 | { |
| 4575 | fprintf(f, "MEMORY {\n"); |
| 4576 | for (Memory_regions::const_iterator m = this->memory_regions_->begin(); |
| 4577 | m != this->memory_regions_->end(); |
| 4578 | ++m) |
| 4579 | (*m)->print(f); |
| 4580 | fprintf(f, "}\n"); |
| 4581 | } |
| 4582 | |
| 4583 | if (!this->saw_sections_clause_) |
| 4584 | return; |
| 4585 | |
| 4586 | fprintf(f, "SECTIONS {\n"); |
| 4587 | |
| 4588 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 4589 | p != this->sections_elements_->end(); |
| 4590 | ++p) |
| 4591 | (*p)->print(f); |
| 4592 | |
| 4593 | fprintf(f, "}\n"); |
| 4594 | } |
| 4595 | |
| 4596 | } // End namespace gold. |