gold/reloc.cc

   1 // reloc.cc -- relocate input files for gold.
   2
   3 // Copyright 2006, 2007 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 "workqueue.h"
  26 #include "object.h"
  27 #include "symtab.h"
  28 #include "output.h"
  29 #include "reloc.h"
  30
  31 namespace gold
  32 {
  33
  34 // Read_relocs methods.
  35
  36 // These tasks just read the relocation information from the file.
  37 // After reading it, the start another task to process the
  38 // information.  These tasks requires access to the file.
  39
  40 Task::Is_runnable_type
  41 Read_relocs::is_runnable(Workqueue*)
  42 {
  43   return this->object_->is_locked() ? IS_LOCKED : IS_RUNNABLE;
  44 }
  45
  46 // Lock the file.
  47
  48 Task_locker*
  49 Read_relocs::locks(Workqueue*)
  50 {
  51   return new Task_locker_obj<Object>(*this->object_);
  52 }
  53
  54 // Read the relocations and then start a Scan_relocs_task.
  55
  56 void
  57 Read_relocs::run(Workqueue* workqueue)
  58 {
  59   Read_relocs_data *rd = new Read_relocs_data;
  60   this->object_->read_relocs(rd);
  61   workqueue->queue_front(new Scan_relocs(this->options_, this->symtab_,
  62                                          this->layout_, this->object_, rd,
  63                                          this->symtab_lock_, this->blocker_));
  64 }
  65
  66 // Return a debugging name for the task.
  67
  68 std::string
  69 Read_relocs::get_name() const
  70 {
  71   return "Read_relocs " + this->object_->name();
  72 }
  73
  74 // Scan_relocs methods.
  75
  76 // These tasks scan the relocations read by Read_relocs and mark up
  77 // the symbol table to indicate which relocations are required.  We
  78 // use a lock on the symbol table to keep them from interfering with
  79 // each other.
  80
  81 Task::Is_runnable_type
  82 Scan_relocs::is_runnable(Workqueue*)
  83 {
  84   if (!this->symtab_lock_->is_writable() || this->object_->is_locked())
  85     return IS_LOCKED;
  86   return IS_RUNNABLE;
  87 }
  88
  89 // Return the locks we hold: one on the file, one on the symbol table
  90 // and one blocker.
  91
  92 class Scan_relocs::Scan_relocs_locker : public Task_locker
  93 {
  94  public:
  95   Scan_relocs_locker(Object* object, Task_token& symtab_lock, Task* task,
  96                      Task_token& blocker, Workqueue* workqueue)
  97     : objlock_(*object), symtab_locker_(symtab_lock, task),
  98       blocker_(blocker, workqueue)
  99   { }
 100
 101  private:
 102   Task_locker_obj<Object> objlock_;
 103   Task_locker_write symtab_locker_;
 104   Task_locker_block blocker_;
 105 };
 106
 107 Task_locker*
 108 Scan_relocs::locks(Workqueue* workqueue)
 109 {
 110   return new Scan_relocs_locker(this->object_, *this->symtab_lock_, this,
 111                                 *this->blocker_, workqueue);
 112 }
 113
 114 // Scan the relocs.
 115
 116 void
 117 Scan_relocs::run(Workqueue*)
 118 {
 119   this->object_->scan_relocs(this->options_, this->symtab_, this->layout_,
 120                              this->rd_);
 121   delete this->rd_;
 122   this->rd_ = NULL;
 123 }
 124
 125 // Return a debugging name for the task.
 126
 127 std::string
 128 Scan_relocs::get_name() const
 129 {
 130   return "Scan_relocs " + this->object_->name();
 131 }
 132
 133 // Relocate_task methods.
 134
 135 // We may have to wait for the output sections to be written.
 136
 137 Task::Is_runnable_type
 138 Relocate_task::is_runnable(Workqueue*)
 139 {
 140   if (this->object_->relocs_must_follow_section_writes()
 141       && this->output_sections_blocker_->is_blocked())
 142     return IS_BLOCKED;
 143
 144   if (this->object_->is_locked())
 145     return IS_LOCKED;
 146
 147   return IS_RUNNABLE;
 148 }
 149
 150 // We want to lock the file while we run.  We want to unblock
 151 // INPUT_SECTIONS_BLOCKER and FINAL_BLOCKER when we are done.
 152
 153 class Relocate_task::Relocate_locker : public Task_locker
 154 {
 155  public:
 156   Relocate_locker(Task_token& input_sections_blocker,
 157                   Task_token& final_blocker, Workqueue* workqueue,
 158                   Object* object)
 159     : input_sections_blocker_(input_sections_blocker, workqueue),
 160       final_blocker_(final_blocker, workqueue),
 161       objlock_(*object)
 162   { }
 163
 164  private:
 165   Task_block_token input_sections_blocker_;
 166   Task_block_token final_blocker_;
 167   Task_locker_obj<Object> objlock_;
 168 };
 169
 170 Task_locker*
 171 Relocate_task::locks(Workqueue* workqueue)
 172 {
 173   return new Relocate_locker(*this->input_sections_blocker_,
 174                              *this->final_blocker_,
 175                              workqueue,
 176                              this->object_);
 177 }
 178
 179 // Run the task.
 180
 181 void
 182 Relocate_task::run(Workqueue*)
 183 {
 184   this->object_->relocate(this->options_, this->symtab_, this->layout_,
 185                           this->of_);
 186 }
 187
 188 // Return a debugging name for the task.
 189
 190 std::string
 191 Relocate_task::get_name() const
 192 {
 193   return "Relocate_task " + this->object_->name();
 194 }
 195
 196 // Read the relocs and local symbols from the object file and store
 197 // the information in RD.
 198
 199 template<int size, bool big_endian>
 200 void
 201 Sized_relobj<size, big_endian>::do_read_relocs(Read_relocs_data* rd)
 202 {
 203   rd->relocs.clear();
 204
 205   unsigned int shnum = this->shnum();
 206   if (shnum == 0)
 207     return;
 208
 209   rd->relocs.reserve(shnum / 2);
 210
 211   std::vector<Map_to_output>& map_sections(this->map_to_output());
 212
 213   const unsigned char *pshdrs = this->get_view(this->elf_file_.shoff(),
 214                                                shnum * This::shdr_size,
 215                                                true);
 216   // Skip the first, dummy, section.
 217   const unsigned char *ps = pshdrs + This::shdr_size;
 218   for (unsigned int i = 1; i < shnum; ++i, ps += This::shdr_size)
 219     {
 220       typename This::Shdr shdr(ps);
 221
 222       unsigned int sh_type = shdr.get_sh_type();
 223       if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
 224         continue;
 225
 226       unsigned int shndx = shdr.get_sh_info();
 227       if (shndx >= shnum)
 228         {
 229           this->error(_("relocation section %u has bad info %u"),
 230                       i, shndx);
 231           continue;
 232         }
 233
 234       Output_section* os = map_sections[shndx].output_section;
 235       if (os == NULL)
 236         continue;
 237
 238       // We are scanning relocations in order to fill out the GOT and
 239       // PLT sections.  Relocations for sections which are not
 240       // allocated (typically debugging sections) should not add new
 241       // GOT and PLT entries.  So we skip them.
 242       typename This::Shdr secshdr(pshdrs + shndx * This::shdr_size);
 243       if ((secshdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
 244         continue;
 245
 246       if (shdr.get_sh_link() != this->symtab_shndx_)
 247         {
 248           this->error(_("relocation section %u uses unexpected "
 249                         "symbol table %u"),
 250                       i, shdr.get_sh_link());
 251           continue;
 252         }
 253
 254       off_t sh_size = shdr.get_sh_size();
 255
 256       unsigned int reloc_size;
 257       if (sh_type == elfcpp::SHT_REL)
 258         reloc_size = elfcpp::Elf_sizes<size>::rel_size;
 259       else
 260         reloc_size = elfcpp::Elf_sizes<size>::rela_size;
 261       if (reloc_size != shdr.get_sh_entsize())
 262         {
 263           this->error(_("unexpected entsize for reloc section %u: %lu != %u"),
 264                       i, static_cast<unsigned long>(shdr.get_sh_entsize()),
 265                       reloc_size);
 266           continue;
 267         }
 268
 269       size_t reloc_count = sh_size / reloc_size;
 270       if (static_cast<off_t>(reloc_count * reloc_size) != sh_size)
 271         {
 272           this->error(_("reloc section %u size %lu uneven"),
 273                       i, static_cast<unsigned long>(sh_size));
 274           continue;
 275         }
 276
 277       rd->relocs.push_back(Section_relocs());
 278       Section_relocs& sr(rd->relocs.back());
 279       sr.reloc_shndx = i;
 280       sr.data_shndx = shndx;
 281       sr.contents = this->get_lasting_view(shdr.get_sh_offset(), sh_size,
 282                                            true);
 283       sr.sh_type = sh_type;
 284       sr.reloc_count = reloc_count;
 285       sr.output_section = os;
 286       sr.needs_special_offset_handling = map_sections[shndx].offset == -1;
 287     }
 288
 289   // Read the local symbols.
 290   gold_assert(this->symtab_shndx_ != -1U);
 291   if (this->symtab_shndx_ == 0 || this->local_symbol_count_ == 0)
 292     rd->local_symbols = NULL;
 293   else
 294     {
 295       typename This::Shdr symtabshdr(pshdrs
 296                                      + this->symtab_shndx_ * This::shdr_size);
 297       gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
 298       const int sym_size = This::sym_size;
 299       const unsigned int loccount = this->local_symbol_count_;
 300       gold_assert(loccount == symtabshdr.get_sh_info());
 301       off_t locsize = loccount * sym_size;
 302       rd->local_symbols = this->get_lasting_view(symtabshdr.get_sh_offset(),
 303                                                  locsize, true);
 304     }
 305 }
 306
 307 // Scan the relocs and adjust the symbol table.  This looks for
 308 // relocations which require GOT/PLT/COPY relocations.
 309
 310 template<int size, bool big_endian>
 311 void
 312 Sized_relobj<size, big_endian>::do_scan_relocs(const General_options& options,
 313                                                Symbol_table* symtab,
 314                                                Layout* layout,
 315                                                Read_relocs_data* rd)
 316 {
 317   Sized_target<size, big_endian>* target = this->sized_target();
 318
 319   const unsigned char* local_symbols;
 320   if (rd->local_symbols == NULL)
 321     local_symbols = NULL;
 322   else
 323     local_symbols = rd->local_symbols->data();
 324
 325   for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin();
 326        p != rd->relocs.end();
 327        ++p)
 328     {
 329       target->scan_relocs(options, symtab, layout, this, p->data_shndx,
 330                           p->sh_type, p->contents->data(), p->reloc_count,
 331                           p->output_section, p->needs_special_offset_handling,
 332                           this->local_symbol_count_,
 333                           local_symbols);
 334       delete p->contents;
 335       p->contents = NULL;
 336     }
 337
 338   if (rd->local_symbols != NULL)
 339     {
 340       delete rd->local_symbols;
 341       rd->local_symbols = NULL;
 342     }
 343 }
 344
 345 // Relocate the input sections and write out the local symbols.
 346
 347 template<int size, bool big_endian>
 348 void
 349 Sized_relobj<size, big_endian>::do_relocate(const General_options& options,
 350                                             const Symbol_table* symtab,
 351                                             const Layout* layout,
 352                                             Output_file* of)
 353 {
 354   unsigned int shnum = this->shnum();
 355
 356   // Read the section headers.
 357   const unsigned char* pshdrs = this->get_view(this->elf_file_.shoff(),
 358                                                shnum * This::shdr_size,
 359                                                true);
 360
 361   Views views;
 362   views.resize(shnum);
 363
 364   // Make two passes over the sections.  The first one copies the
 365   // section data to the output file.  The second one applies
 366   // relocations.
 367
 368   this->write_sections(pshdrs, of, &views);
 369
 370   // Apply relocations.
 371
 372   this->relocate_sections(options, symtab, layout, pshdrs, &views);
 373
 374   // Write out the accumulated views.
 375   for (unsigned int i = 1; i < shnum; ++i)
 376     {
 377       if (views[i].view != NULL)
 378         {
 379           if (views[i].is_input_output_view)
 380             of->write_input_output_view(views[i].offset, views[i].view_size,
 381                                         views[i].view);
 382           else
 383             of->write_output_view(views[i].offset, views[i].view_size,
 384                                   views[i].view);
 385         }
 386     }
 387
 388   // Write out the local symbols.
 389   this->write_local_symbols(of, layout->sympool());
 390 }
 391
 392 // Write section data to the output file.  PSHDRS points to the
 393 // section headers.  Record the views in *PVIEWS for use when
 394 // relocating.
 395
 396 template<int size, bool big_endian>
 397 void
 398 Sized_relobj<size, big_endian>::write_sections(const unsigned char* pshdrs,
 399                                                Output_file* of,
 400                                                Views* pviews)
 401 {
 402   unsigned int shnum = this->shnum();
 403   std::vector<Map_to_output>& map_sections(this->map_to_output());
 404
 405   const unsigned char* p = pshdrs + This::shdr_size;
 406   for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
 407     {
 408       View_size* pvs = &(*pviews)[i];
 409
 410       pvs->view = NULL;
 411
 412       const Output_section* os = map_sections[i].output_section;
 413       if (os == NULL)
 414         continue;
 415       off_t output_offset = map_sections[i].offset;
 416
 417       typename This::Shdr shdr(p);
 418
 419       if (shdr.get_sh_type() == elfcpp::SHT_NOBITS)
 420         continue;
 421
 422       off_t view_start;
 423       off_t view_size;
 424       if (output_offset != -1)
 425         {
 426           view_start = os->offset() + output_offset;
 427           view_size = shdr.get_sh_size();
 428         }
 429       else
 430         {
 431           view_start = os->offset();
 432           view_size = os->data_size();
 433         }
 434
 435       if (view_size == 0)
 436         continue;
 437
 438       gold_assert(output_offset == -1
 439                   || (output_offset >= 0
 440                       && output_offset + view_size <= os->data_size()));
 441
 442       unsigned char* view;
 443       if (output_offset == -1)
 444         view = of->get_input_output_view(view_start, view_size);
 445       else
 446         {
 447           view = of->get_output_view(view_start, view_size);
 448           this->read(shdr.get_sh_offset(), view_size, view);
 449         }
 450
 451       pvs->view = view;
 452       pvs->address = os->address();
 453       if (output_offset != -1)
 454         pvs->address += output_offset;
 455       pvs->offset = view_start;
 456       pvs->view_size = view_size;
 457       pvs->is_input_output_view = output_offset == -1;
 458     }
 459 }
 460
 461 // Relocate section data.  VIEWS points to the section data as views
 462 // in the output file.
 463
 464 template<int size, bool big_endian>
 465 void
 466 Sized_relobj<size, big_endian>::relocate_sections(
 467     const General_options& options,
 468     const Symbol_table* symtab,
 469     const Layout* layout,
 470     const unsigned char* pshdrs,
 471     Views* pviews)
 472 {
 473   unsigned int shnum = this->shnum();
 474   Sized_target<size, big_endian>* target = this->sized_target();
 475
 476   std::vector<Map_to_output>& map_sections(this->map_to_output());
 477
 478   Relocate_info<size, big_endian> relinfo;
 479   relinfo.options = &options;
 480   relinfo.symtab = symtab;
 481   relinfo.layout = layout;
 482   relinfo.object = this;
 483
 484   const unsigned char* p = pshdrs + This::shdr_size;
 485   for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
 486     {
 487       typename This::Shdr shdr(p);
 488
 489       unsigned int sh_type = shdr.get_sh_type();
 490       if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
 491         continue;
 492
 493       unsigned int index = shdr.get_sh_info();
 494       if (index >= this->shnum())
 495         {
 496           this->error(_("relocation section %u has bad info %u"),
 497                       i, index);
 498           continue;
 499         }
 500
 501       Output_section* os = map_sections[index].output_section;
 502       if (os == NULL)
 503         {
 504           // This relocation section is against a section which we
 505           // discarded.
 506           continue;
 507         }
 508       off_t output_offset = map_sections[index].offset;
 509
 510       gold_assert((*pviews)[index].view != NULL);
 511
 512       if (shdr.get_sh_link() != this->symtab_shndx_)
 513         {
 514           gold_error(_("relocation section %u uses unexpected "
 515                        "symbol table %u"),
 516                      i, shdr.get_sh_link());
 517           continue;
 518         }
 519
 520       off_t sh_size = shdr.get_sh_size();
 521       const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
 522                                                     sh_size, false);
 523
 524       unsigned int reloc_size;
 525       if (sh_type == elfcpp::SHT_REL)
 526         reloc_size = elfcpp::Elf_sizes<size>::rel_size;
 527       else
 528         reloc_size = elfcpp::Elf_sizes<size>::rela_size;
 529
 530       if (reloc_size != shdr.get_sh_entsize())
 531         {
 532           gold_error(_("unexpected entsize for reloc section %u: %lu != %u"),
 533                      i, static_cast<unsigned long>(shdr.get_sh_entsize()),
 534                      reloc_size);
 535           continue;
 536         }
 537
 538       size_t reloc_count = sh_size / reloc_size;
 539       if (static_cast<off_t>(reloc_count * reloc_size) != sh_size)
 540         {
 541           gold_error(_("reloc section %u size %lu uneven"),
 542                      i, static_cast<unsigned long>(sh_size));
 543           continue;
 544         }
 545
 546       relinfo.reloc_shndx = i;
 547       relinfo.data_shndx = index;
 548       target->relocate_section(&relinfo,
 549                                sh_type,
 550                                prelocs,
 551                                reloc_count,
 552                                os,
 553                                output_offset == -1,
 554                                (*pviews)[index].view,
 555                                (*pviews)[index].address,
 556                                (*pviews)[index].view_size);
 557     }
 558 }
 559
 560 // Copy_relocs::Copy_reloc_entry methods.
 561
 562 // Return whether we should emit this reloc.  We should emit it if the
 563 // symbol is still defined in a dynamic object.  If we should not emit
 564 // it, we clear it, to save ourselves the test next time.
 565
 566 template<int size, bool big_endian>
 567 bool
 568 Copy_relocs<size, big_endian>::Copy_reloc_entry::should_emit()
 569 {
 570   if (this->sym_ == NULL)
 571     return false;
 572   if (this->sym_->is_from_dynobj())
 573     return true;
 574   this->sym_ = NULL;
 575   return false;
 576 }
 577
 578 // Emit a reloc into a SHT_REL section.
 579
 580 template<int size, bool big_endian>
 581 void
 582 Copy_relocs<size, big_endian>::Copy_reloc_entry::emit(
 583     Output_data_reloc<elfcpp::SHT_REL, true, size, big_endian>* reloc_data)
 584 {
 585   this->sym_->set_needs_dynsym_entry();
 586   reloc_data->add_global(this->sym_, this->reloc_type_, this->output_section_,
 587                          this->relobj_, this->shndx_, this->address_);
 588 }
 589
 590 // Emit a reloc into a SHT_RELA section.
 591
 592 template<int size, bool big_endian>
 593 void
 594 Copy_relocs<size, big_endian>::Copy_reloc_entry::emit(
 595     Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>* reloc_data)
 596 {
 597   this->sym_->set_needs_dynsym_entry();
 598   reloc_data->add_global(this->sym_, this->reloc_type_, this->output_section_,
 599                          this->relobj_, this->shndx_, this->address_,
 600                          this->addend_);
 601 }
 602
 603 // Copy_relocs methods.
 604
 605 // Return whether we need a COPY reloc for a relocation against GSYM.
 606 // The relocation is being applied to section SHNDX in OBJECT.
 607
 608 template<int size, bool big_endian>
 609 bool
 610 Copy_relocs<size, big_endian>::need_copy_reloc(
 611     const General_options*,
 612     Relobj* object,
 613     unsigned int shndx,
 614     Sized_symbol<size>* sym)
 615 {
 616   // FIXME: Handle -z nocopyrelocs.
 617
 618   if (sym->symsize() == 0)
 619     return false;
 620
 621   // If this is a readonly section, then we need a COPY reloc.
 622   // Otherwise we can use a dynamic reloc.
 623   if ((object->section_flags(shndx) & elfcpp::SHF_WRITE) == 0)
 624     return true;
 625
 626   return false;
 627 }
 628
 629 // Save a Rel reloc.
 630
 631 template<int size, bool big_endian>
 632 void
 633 Copy_relocs<size, big_endian>::save(
 634     Symbol* sym,
 635     Relobj* relobj,
 636     unsigned int shndx,
 637     Output_section* output_section,
 638     const elfcpp::Rel<size, big_endian>& rel)
 639 {
 640   unsigned int reloc_type = elfcpp::elf_r_type<size>(rel.get_r_info());
 641   this->entries_.push_back(Copy_reloc_entry(sym, reloc_type, relobj, shndx,
 642                                             output_section,
 643                                             rel.get_r_offset(), 0));
 644 }
 645
 646 // Save a Rela reloc.
 647
 648 template<int size, bool big_endian>
 649 void
 650 Copy_relocs<size, big_endian>::save(
 651     Symbol* sym,
 652     Relobj* relobj,
 653     unsigned int shndx,
 654     Output_section* output_section,
 655     const elfcpp::Rela<size, big_endian>& rela)
 656 {
 657   unsigned int reloc_type = elfcpp::elf_r_type<size>(rela.get_r_info());
 658   this->entries_.push_back(Copy_reloc_entry(sym, reloc_type, relobj, shndx,
 659                                             output_section,
 660                                             rela.get_r_offset(),
 661                                             rela.get_r_addend()));
 662 }
 663
 664 // Return whether there are any relocs to emit.  We don't want to emit
 665 // a reloc if the symbol is no longer defined in a dynamic object.
 666
 667 template<int size, bool big_endian>
 668 bool
 669 Copy_relocs<size, big_endian>::any_to_emit()
 670 {
 671   for (typename Copy_reloc_entries::iterator p = this->entries_.begin();
 672        p != this->entries_.end();
 673        ++p)
 674     {
 675       if (p->should_emit())
 676         return true;
 677     }
 678   return false;
 679 }
 680
 681 // Emit relocs.
 682
 683 template<int size, bool big_endian>
 684 template<int sh_type>
 685 void
 686 Copy_relocs<size, big_endian>::emit(
 687     Output_data_reloc<sh_type, true, size, big_endian>* reloc_data)
 688 {
 689   for (typename Copy_reloc_entries::iterator p = this->entries_.begin();
 690        p != this->entries_.end();
 691        ++p)
 692     {
 693       if (p->should_emit())
 694         p->emit(reloc_data);
 695     }
 696 }
 697
 698 // Track_relocs methods.
 699
 700 // Initialize the class to track the relocs.  This gets the object,
 701 // the reloc section index, and the type of the relocs.  This returns
 702 // false if something goes wrong.
 703
 704 template<int size, bool big_endian>
 705 bool
 706 Track_relocs<size, big_endian>::initialize(
 707     Object* object,
 708     unsigned int reloc_shndx,
 709     unsigned int reloc_type)
 710 {
 711   // If RELOC_SHNDX is -1U, it means there is more than one reloc
 712   // section for the .eh_frame section.  We can't handle that case.
 713   if (reloc_shndx == -1U)
 714     return false;
 715
 716   // If RELOC_SHNDX is 0, there is no reloc section.
 717   if (reloc_shndx == 0)
 718     return true;
 719
 720   // Get the contents of the reloc section.
 721   this->prelocs_ = object->section_contents(reloc_shndx, &this->len_, false);
 722
 723   if (reloc_type == elfcpp::SHT_REL)
 724     this->reloc_size_ = elfcpp::Elf_sizes<size>::rel_size;
 725   else if (reloc_type == elfcpp::SHT_RELA)
 726     this->reloc_size_ = elfcpp::Elf_sizes<size>::rela_size;
 727   else
 728     gold_unreachable();
 729
 730   if (this->len_ % this->reloc_size_ != 0)
 731     {
 732       object->error(_("reloc section size %zu is not a multiple of "
 733                       "reloc size %d\n"),
 734                     static_cast<size_t>(this->len_),
 735                     this->reloc_size_);
 736       return false;
 737     }
 738
 739   return true;
 740 }
 741
 742 // Return the offset of the next reloc, or -1 if there isn't one.
 743
 744 template<int size, bool big_endian>
 745 off_t
 746 Track_relocs<size, big_endian>::next_offset() const
 747 {
 748   if (this->pos_ >= this->len_)
 749     return -1;
 750
 751   // Rel and Rela start out the same, so we can always use Rel to find
 752   // the r_offset value.
 753   elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
 754   return rel.get_r_offset();
 755 }
 756
 757 // Return the index of the symbol referenced by the next reloc, or -1U
 758 // if there aren't any more relocs.
 759
 760 template<int size, bool big_endian>
 761 unsigned int
 762 Track_relocs<size, big_endian>::next_symndx() const
 763 {
 764   if (this->pos_ >= this->len_)
 765     return -1U;
 766
 767   // Rel and Rela start out the same, so we can use Rel to find the
 768   // symbol index.
 769   elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
 770   return elfcpp::elf_r_sym<size>(rel.get_r_info());
 771 }
 772
 773 // Advance to the next reloc whose r_offset is greater than or equal
 774 // to OFFSET.  Return the number of relocs we skip.
 775
 776 template<int size, bool big_endian>
 777 int
 778 Track_relocs<size, big_endian>::advance(off_t offset)
 779 {
 780   int ret = 0;
 781   while (this->pos_ < this->len_)
 782     {
 783       // Rel and Rela start out the same, so we can always use Rel to
 784       // find the r_offset value.
 785       elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
 786       if (static_cast<off_t>(rel.get_r_offset()) >= offset)
 787         break;
 788       ++ret;
 789       this->pos_ += this->reloc_size_;
 790     }
 791   return ret;
 792 }
 793
 794 // Instantiate the templates we need.  We could use the configure
 795 // script to restrict this to only the ones for implemented targets.
 796
 797 #ifdef HAVE_TARGET_32_LITTLE
 798 template
 799 void
 800 Sized_relobj<32, false>::do_read_relocs(Read_relocs_data* rd);
 801 #endif
 802
 803 #ifdef HAVE_TARGET_32_BIG
 804 template
 805 void
 806 Sized_relobj<32, true>::do_read_relocs(Read_relocs_data* rd);
 807 #endif
 808
 809 #ifdef HAVE_TARGET_64_LITTLE
 810 template
 811 void
 812 Sized_relobj<64, false>::do_read_relocs(Read_relocs_data* rd);
 813 #endif
 814
 815 #ifdef HAVE_TARGET_64_BIG
 816 template
 817 void
 818 Sized_relobj<64, true>::do_read_relocs(Read_relocs_data* rd);
 819 #endif
 820
 821 #ifdef HAVE_TARGET_32_LITTLE
 822 template
 823 void
 824 Sized_relobj<32, false>::do_scan_relocs(const General_options& options,
 825                                         Symbol_table* symtab,
 826                                         Layout* layout,
 827                                         Read_relocs_data* rd);
 828 #endif
 829
 830 #ifdef HAVE_TARGET_32_BIG
 831 template
 832 void
 833 Sized_relobj<32, true>::do_scan_relocs(const General_options& options,
 834                                        Symbol_table* symtab,
 835                                        Layout* layout,
 836                                        Read_relocs_data* rd);
 837 #endif
 838
 839 #ifdef HAVE_TARGET_64_LITTLE
 840 template
 841 void
 842 Sized_relobj<64, false>::do_scan_relocs(const General_options& options,
 843                                         Symbol_table* symtab,
 844                                         Layout* layout,
 845                                         Read_relocs_data* rd);
 846 #endif
 847
 848 #ifdef HAVE_TARGET_64_BIG
 849 template
 850 void
 851 Sized_relobj<64, true>::do_scan_relocs(const General_options& options,
 852                                        Symbol_table* symtab,
 853                                        Layout* layout,
 854                                        Read_relocs_data* rd);
 855 #endif
 856
 857 #ifdef HAVE_TARGET_32_LITTLE
 858 template
 859 void
 860 Sized_relobj<32, false>::do_relocate(const General_options& options,
 861                                      const Symbol_table* symtab,
 862                                      const Layout* layout,
 863                                      Output_file* of);
 864 #endif
 865
 866 #ifdef HAVE_TARGET_32_BIG
 867 template
 868 void
 869 Sized_relobj<32, true>::do_relocate(const General_options& options,
 870                                     const Symbol_table* symtab,
 871                                     const Layout* layout,
 872                                     Output_file* of);
 873 #endif
 874
 875 #ifdef HAVE_TARGET_64_LITTLE
 876 template
 877 void
 878 Sized_relobj<64, false>::do_relocate(const General_options& options,
 879                                      const Symbol_table* symtab,
 880                                      const Layout* layout,
 881                                      Output_file* of);
 882 #endif
 883
 884 #ifdef HAVE_TARGET_64_BIG
 885 template
 886 void
 887 Sized_relobj<64, true>::do_relocate(const General_options& options,
 888                                     const Symbol_table* symtab,
 889                                     const Layout* layout,
 890                                     Output_file* of);
 891 #endif
 892
 893 #ifdef HAVE_TARGET_32_LITTLE
 894 template
 895 class Copy_relocs<32, false>;
 896 #endif
 897
 898 #ifdef HAVE_TARGET_32_BIG
 899 template
 900 class Copy_relocs<32, true>;
 901 #endif
 902
 903 #ifdef HAVE_TARGET_64_LITTLE
 904 template
 905 class Copy_relocs<64, false>;
 906 #endif
 907
 908 #ifdef HAVE_TARGET_64_BIG
 909 template
 910 class Copy_relocs<64, true>;
 911 #endif
 912
 913 #ifdef HAVE_TARGET_32_LITTLE
 914 template
 915 void
 916 Copy_relocs<32, false>::emit<elfcpp::SHT_REL>(
 917     Output_data_reloc<elfcpp::SHT_REL, true, 32, false>*);
 918 #endif
 919
 920 #ifdef HAVE_TARGET_32_BIG
 921 template
 922 void
 923 Copy_relocs<32, true>::emit<elfcpp::SHT_REL>(
 924     Output_data_reloc<elfcpp::SHT_REL, true, 32, true>*);
 925 #endif
 926
 927 #ifdef HAVE_TARGET_64_LITTLE
 928 template
 929 void
 930 Copy_relocs<64, false>::emit<elfcpp::SHT_REL>(
 931     Output_data_reloc<elfcpp::SHT_REL, true, 64, false>*);
 932 #endif
 933
 934 #ifdef HAVE_TARGET_64_BIG
 935 template
 936 void
 937 Copy_relocs<64, true>::emit<elfcpp::SHT_REL>(
 938     Output_data_reloc<elfcpp::SHT_REL, true, 64, true>*);
 939 #endif
 940
 941 #ifdef HAVE_TARGET_32_LITTLE
 942 template
 943 void
 944 Copy_relocs<32, false>::emit<elfcpp::SHT_RELA>(
 945     Output_data_reloc<elfcpp::SHT_RELA , true, 32, false>*);
 946 #endif
 947
 948 #ifdef HAVE_TARGET_32_BIG
 949 template
 950 void
 951 Copy_relocs<32, true>::emit<elfcpp::SHT_RELA>(
 952     Output_data_reloc<elfcpp::SHT_RELA, true, 32, true>*);
 953 #endif
 954
 955 #ifdef HAVE_TARGET_64_LITTLE
 956 template
 957 void
 958 Copy_relocs<64, false>::emit<elfcpp::SHT_RELA>(
 959     Output_data_reloc<elfcpp::SHT_RELA, true, 64, false>*);
 960 #endif
 961
 962 #ifdef HAVE_TARGET_64_BIG
 963 template
 964 void
 965 Copy_relocs<64, true>::emit<elfcpp::SHT_RELA>(
 966     Output_data_reloc<elfcpp::SHT_RELA, true, 64, true>*);
 967 #endif
 968
 969 #ifdef HAVE_TARGET_32_LITTLE
 970 template
 971 class Track_relocs<32, false>;
 972 #endif
 973
 974 #ifdef HAVE_TARGET_32_BIG
 975 template
 976 class Track_relocs<32, true>;
 977 #endif
 978
 979 #ifdef HAVE_TARGET_64_LITTLE
 980 template
 981 class Track_relocs<64, false>;
 982 #endif
 983
 984 #ifdef HAVE_TARGET_64_BIG
 985 template
 986 class Track_relocs<64, true>;
 987 #endif
 988
 989 } // End namespace gold.