gold/output.cc

   1 // output.cc -- manage the output file for gold
   2
   3 #include "gold.h"
   4
   5 #include <cstdlib>
   6 #include <cerrno>
   7 #include <fcntl.h>
   8 #include <unistd.h>
   9 #include <sys/mman.h>
  10 #include <algorithm>
  11
  12 #include "object.h"
  13 #include "symtab.h"
  14 #include "reloc.h"
  15 #include "merge.h"
  16 #include "output.h"
  17
  18 namespace gold
  19 {
  20
  21 // Output_data variables.
  22
  23 bool Output_data::sizes_are_fixed;
  24
  25 // Output_data methods.
  26
  27 Output_data::~Output_data()
  28 {
  29 }
  30
  31 // Set the address and offset.
  32
  33 void
  34 Output_data::set_address(uint64_t addr, off_t off)
  35 {
  36   this->address_ = addr;
  37   this->offset_ = off;
  38
  39   // Let the child class know.
  40   this->do_set_address(addr, off);
  41 }
  42
  43 // Return the default alignment for a size--32 or 64.
  44
  45 uint64_t
  46 Output_data::default_alignment(int size)
  47 {
  48   if (size == 32)
  49     return 4;
  50   else if (size == 64)
  51     return 8;
  52   else
  53     gold_unreachable();
  54 }
  55
  56 // Output_section_header methods.  This currently assumes that the
  57 // segment and section lists are complete at construction time.
  58
  59 Output_section_headers::Output_section_headers(
  60     int size,
  61     bool big_endian,
  62     const Layout* layout,
  63     const Layout::Segment_list* segment_list,
  64     const Layout::Section_list* unattached_section_list,
  65     const Stringpool* secnamepool)
  66   : size_(size),
  67     big_endian_(big_endian),
  68     layout_(layout),
  69     segment_list_(segment_list),
  70     unattached_section_list_(unattached_section_list),
  71     secnamepool_(secnamepool)
  72 {
  73   // Count all the sections.  Start with 1 for the null section.
  74   off_t count = 1;
  75   for (Layout::Segment_list::const_iterator p = segment_list->begin();
  76        p != segment_list->end();
  77        ++p)
  78     if ((*p)->type() == elfcpp::PT_LOAD)
  79       count += (*p)->output_section_count();
  80   count += unattached_section_list->size();
  81
  82   int shdr_size;
  83   if (size == 32)
  84     shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
  85   else if (size == 64)
  86     shdr_size = elfcpp::Elf_sizes<64>::shdr_size;
  87   else
  88     gold_unreachable();
  89
  90   this->set_data_size(count * shdr_size);
  91 }
  92
  93 // Write out the section headers.
  94
  95 void
  96 Output_section_headers::do_write(Output_file* of)
  97 {
  98   if (this->size_ == 32)
  99     {
 100       if (this->big_endian_)
 101         this->do_sized_write<32, true>(of);
 102       else
 103         this->do_sized_write<32, false>(of);
 104     }
 105   else if (this->size_ == 64)
 106     {
 107       if (this->big_endian_)
 108         this->do_sized_write<64, true>(of);
 109       else
 110         this->do_sized_write<64, false>(of);
 111     }
 112   else
 113     gold_unreachable();
 114 }
 115
 116 template<int size, bool big_endian>
 117 void
 118 Output_section_headers::do_sized_write(Output_file* of)
 119 {
 120   off_t all_shdrs_size = this->data_size();
 121   unsigned char* view = of->get_output_view(this->offset(), all_shdrs_size);
 122
 123   const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
 124   unsigned char* v = view;
 125
 126   {
 127     typename elfcpp::Shdr_write<size, big_endian> oshdr(v);
 128     oshdr.put_sh_name(0);
 129     oshdr.put_sh_type(elfcpp::SHT_NULL);
 130     oshdr.put_sh_flags(0);
 131     oshdr.put_sh_addr(0);
 132     oshdr.put_sh_offset(0);
 133     oshdr.put_sh_size(0);
 134     oshdr.put_sh_link(0);
 135     oshdr.put_sh_info(0);
 136     oshdr.put_sh_addralign(0);
 137     oshdr.put_sh_entsize(0);
 138   }
 139
 140   v += shdr_size;
 141
 142   unsigned shndx = 1;
 143   for (Layout::Segment_list::const_iterator p = this->segment_list_->begin();
 144        p != this->segment_list_->end();
 145        ++p)
 146     v = (*p)->write_section_headers SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
 147             this->layout_, this->secnamepool_, v, &shndx
 148             SELECT_SIZE_ENDIAN(size, big_endian));
 149   for (Layout::Section_list::const_iterator p =
 150          this->unattached_section_list_->begin();
 151        p != this->unattached_section_list_->end();
 152        ++p)
 153     {
 154       gold_assert(shndx == (*p)->out_shndx());
 155       elfcpp::Shdr_write<size, big_endian> oshdr(v);
 156       (*p)->write_header(this->layout_, this->secnamepool_, &oshdr);
 157       v += shdr_size;
 158       ++shndx;
 159     }
 160
 161   of->write_output_view(this->offset(), all_shdrs_size, view);
 162 }
 163
 164 // Output_segment_header methods.
 165
 166 Output_segment_headers::Output_segment_headers(
 167     int size,
 168     bool big_endian,
 169     const Layout::Segment_list& segment_list)
 170   : size_(size), big_endian_(big_endian), segment_list_(segment_list)
 171 {
 172   int phdr_size;
 173   if (size == 32)
 174     phdr_size = elfcpp::Elf_sizes<32>::phdr_size;
 175   else if (size == 64)
 176     phdr_size = elfcpp::Elf_sizes<64>::phdr_size;
 177   else
 178     gold_unreachable();
 179
 180   this->set_data_size(segment_list.size() * phdr_size);
 181 }
 182
 183 void
 184 Output_segment_headers::do_write(Output_file* of)
 185 {
 186   if (this->size_ == 32)
 187     {
 188       if (this->big_endian_)
 189         this->do_sized_write<32, true>(of);
 190       else
 191         this->do_sized_write<32, false>(of);
 192     }
 193   else if (this->size_ == 64)
 194     {
 195       if (this->big_endian_)
 196         this->do_sized_write<64, true>(of);
 197       else
 198         this->do_sized_write<64, false>(of);
 199     }
 200   else
 201     gold_unreachable();
 202 }
 203
 204 template<int size, bool big_endian>
 205 void
 206 Output_segment_headers::do_sized_write(Output_file* of)
 207 {
 208   const int phdr_size = elfcpp::Elf_sizes<size>::phdr_size;
 209   off_t all_phdrs_size = this->segment_list_.size() * phdr_size;
 210   unsigned char* view = of->get_output_view(this->offset(),
 211                                             all_phdrs_size);
 212   unsigned char* v = view;
 213   for (Layout::Segment_list::const_iterator p = this->segment_list_.begin();
 214        p != this->segment_list_.end();
 215        ++p)
 216     {
 217       elfcpp::Phdr_write<size, big_endian> ophdr(v);
 218       (*p)->write_header(&ophdr);
 219       v += phdr_size;
 220     }
 221
 222   of->write_output_view(this->offset(), all_phdrs_size, view);
 223 }
 224
 225 // Output_file_header methods.
 226
 227 Output_file_header::Output_file_header(int size,
 228                                        bool big_endian,
 229                                        const General_options& options,
 230                                        const Target* target,
 231                                        const Symbol_table* symtab,
 232                                        const Output_segment_headers* osh)
 233   : size_(size),
 234     big_endian_(big_endian),
 235     options_(options),
 236     target_(target),
 237     symtab_(symtab),
 238     segment_header_(osh),
 239     section_header_(NULL),
 240     shstrtab_(NULL)
 241 {
 242   int ehdr_size;
 243   if (size == 32)
 244     ehdr_size = elfcpp::Elf_sizes<32>::ehdr_size;
 245   else if (size == 64)
 246     ehdr_size = elfcpp::Elf_sizes<64>::ehdr_size;
 247   else
 248     gold_unreachable();
 249
 250   this->set_data_size(ehdr_size);
 251 }
 252
 253 // Set the section table information for a file header.
 254
 255 void
 256 Output_file_header::set_section_info(const Output_section_headers* shdrs,
 257                                      const Output_section* shstrtab)
 258 {
 259   this->section_header_ = shdrs;
 260   this->shstrtab_ = shstrtab;
 261 }
 262
 263 // Write out the file header.
 264
 265 void
 266 Output_file_header::do_write(Output_file* of)
 267 {
 268   if (this->size_ == 32)
 269     {
 270       if (this->big_endian_)
 271         this->do_sized_write<32, true>(of);
 272       else
 273         this->do_sized_write<32, false>(of);
 274     }
 275   else if (this->size_ == 64)
 276     {
 277       if (this->big_endian_)
 278         this->do_sized_write<64, true>(of);
 279       else
 280         this->do_sized_write<64, false>(of);
 281     }
 282   else
 283     gold_unreachable();
 284 }
 285
 286 // Write out the file header with appropriate size and endianess.
 287
 288 template<int size, bool big_endian>
 289 void
 290 Output_file_header::do_sized_write(Output_file* of)
 291 {
 292   gold_assert(this->offset() == 0);
 293
 294   int ehdr_size = elfcpp::Elf_sizes<size>::ehdr_size;
 295   unsigned char* view = of->get_output_view(0, ehdr_size);
 296   elfcpp::Ehdr_write<size, big_endian> oehdr(view);
 297
 298   unsigned char e_ident[elfcpp::EI_NIDENT];
 299   memset(e_ident, 0, elfcpp::EI_NIDENT);
 300   e_ident[elfcpp::EI_MAG0] = elfcpp::ELFMAG0;
 301   e_ident[elfcpp::EI_MAG1] = elfcpp::ELFMAG1;
 302   e_ident[elfcpp::EI_MAG2] = elfcpp::ELFMAG2;
 303   e_ident[elfcpp::EI_MAG3] = elfcpp::ELFMAG3;
 304   if (size == 32)
 305     e_ident[elfcpp::EI_CLASS] = elfcpp::ELFCLASS32;
 306   else if (size == 64)
 307     e_ident[elfcpp::EI_CLASS] = elfcpp::ELFCLASS64;
 308   else
 309     gold_unreachable();
 310   e_ident[elfcpp::EI_DATA] = (big_endian
 311                               ? elfcpp::ELFDATA2MSB
 312                               : elfcpp::ELFDATA2LSB);
 313   e_ident[elfcpp::EI_VERSION] = elfcpp::EV_CURRENT;
 314   // FIXME: Some targets may need to set EI_OSABI and EI_ABIVERSION.
 315   oehdr.put_e_ident(e_ident);
 316
 317   elfcpp::ET e_type;
 318   // FIXME: ET_DYN.
 319   if (this->options_.is_relocatable())
 320     e_type = elfcpp::ET_REL;
 321   else
 322     e_type = elfcpp::ET_EXEC;
 323   oehdr.put_e_type(e_type);
 324
 325   oehdr.put_e_machine(this->target_->machine_code());
 326   oehdr.put_e_version(elfcpp::EV_CURRENT);
 327
 328   // FIXME: Need to support -e, and target specific entry symbol.
 329   Symbol* sym = this->symtab_->lookup("_start");
 330   typename Sized_symbol<size>::Value_type v;
 331   if (sym == NULL)
 332     v = 0;
 333   else
 334     {
 335       Sized_symbol<size>* ssym;
 336       ssym = this->symtab_->get_sized_symbol SELECT_SIZE_NAME(size) (
 337         sym SELECT_SIZE(size));
 338       v = ssym->value();
 339     }
 340   oehdr.put_e_entry(v);
 341
 342   oehdr.put_e_phoff(this->segment_header_->offset());
 343   oehdr.put_e_shoff(this->section_header_->offset());
 344
 345   // FIXME: The target needs to set the flags.
 346   oehdr.put_e_flags(0);
 347
 348   oehdr.put_e_ehsize(elfcpp::Elf_sizes<size>::ehdr_size);
 349   oehdr.put_e_phentsize(elfcpp::Elf_sizes<size>::phdr_size);
 350   oehdr.put_e_phnum(this->segment_header_->data_size()
 351                      / elfcpp::Elf_sizes<size>::phdr_size);
 352   oehdr.put_e_shentsize(elfcpp::Elf_sizes<size>::shdr_size);
 353   oehdr.put_e_shnum(this->section_header_->data_size()
 354                      / elfcpp::Elf_sizes<size>::shdr_size);
 355   oehdr.put_e_shstrndx(this->shstrtab_->out_shndx());
 356
 357   of->write_output_view(0, ehdr_size, view);
 358 }
 359
 360 // Output_data_const methods.
 361
 362 void
 363 Output_data_const::do_write(Output_file* of)
 364 {
 365   of->write(this->offset(), this->data_.data(), this->data_.size());
 366 }
 367
 368 // Output_data_const_buffer methods.
 369
 370 void
 371 Output_data_const_buffer::do_write(Output_file* of)
 372 {
 373   of->write(this->offset(), this->p_, this->data_size());
 374 }
 375
 376 // Output_section_data methods.
 377
 378 // Record the output section, and set the entry size and such.
 379
 380 void
 381 Output_section_data::set_output_section(Output_section* os)
 382 {
 383   gold_assert(this->output_section_ == NULL);
 384   this->output_section_ = os;
 385   this->do_adjust_output_section(os);
 386 }
 387
 388 // Return the section index of the output section.
 389
 390 unsigned int
 391 Output_section_data::do_out_shndx() const
 392 {
 393   gold_assert(this->output_section_ != NULL);
 394   return this->output_section_->out_shndx();
 395 }
 396
 397 // Output_data_strtab methods.
 398
 399 // Set the address.  We don't actually care about the address, but we
 400 // do set our final size.
 401
 402 void
 403 Output_data_strtab::do_set_address(uint64_t, off_t)
 404 {
 405   this->strtab_->set_string_offsets();
 406   this->set_data_size(this->strtab_->get_strtab_size());
 407 }
 408
 409 // Write out a string table.
 410
 411 void
 412 Output_data_strtab::do_write(Output_file* of)
 413 {
 414   this->strtab_->write(of, this->offset());
 415 }
 416
 417 // Output_reloc methods.
 418
 419 // Get the symbol index of a relocation.
 420
 421 template<bool dynamic, int size, bool big_endian>
 422 unsigned int
 423 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::get_symbol_index()
 424   const
 425 {
 426   unsigned int index;
 427   switch (this->local_sym_index_)
 428     {
 429     case INVALID_CODE:
 430       gold_unreachable();
 431
 432     case GSYM_CODE:
 433       if (this->u1_.gsym == NULL)
 434         index = 0;
 435       else if (dynamic)
 436         index = this->u1_.gsym->dynsym_index();
 437       else
 438         index = this->u1_.gsym->symtab_index();
 439       break;
 440
 441     case SECTION_CODE:
 442       if (dynamic)
 443         index = this->u1_.os->dynsym_index();
 444       else
 445         index = this->u1_.os->symtab_index();
 446       break;
 447
 448     default:
 449       if (dynamic)
 450         {
 451           // FIXME: It seems that some targets may need to generate
 452           // dynamic relocations against local symbols for some
 453           // reasons.  This will have to be addressed at some point.
 454           gold_unreachable();
 455         }
 456       else
 457         index = this->u1_.relobj->symtab_index(this->local_sym_index_);
 458       break;
 459     }
 460   gold_assert(index != -1U);
 461   return index;
 462 }
 463
 464 // Write out the offset and info fields of a Rel or Rela relocation
 465 // entry.
 466
 467 template<bool dynamic, int size, bool big_endian>
 468 template<typename Write_rel>
 469 void
 470 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write_rel(
 471     Write_rel* wr) const
 472 {
 473   Address address = this->address_;
 474   if (this->shndx_ != INVALID_CODE)
 475     {
 476       off_t off;
 477       Output_section* os = this->u2_.relobj->output_section(this->shndx_,
 478                                                             &off);
 479       gold_assert(os != NULL);
 480       address += os->address() + off;
 481     }
 482   else if (this->u2_.od != NULL)
 483     address += this->u2_.od->address();
 484   wr->put_r_offset(address);
 485   wr->put_r_info(elfcpp::elf_r_info<size>(this->get_symbol_index(),
 486                                           this->type_));
 487 }
 488
 489 // Write out a Rel relocation.
 490
 491 template<bool dynamic, int size, bool big_endian>
 492 void
 493 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write(
 494     unsigned char* pov) const
 495 {
 496   elfcpp::Rel_write<size, big_endian> orel(pov);
 497   this->write_rel(&orel);
 498 }
 499
 500 // Write out a Rela relocation.
 501
 502 template<bool dynamic, int size, bool big_endian>
 503 void
 504 Output_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian>::write(
 505     unsigned char* pov) const
 506 {
 507   elfcpp::Rela_write<size, big_endian> orel(pov);
 508   this->rel_.write_rel(&orel);
 509   orel.put_r_addend(this->addend_);
 510 }
 511
 512 // Output_data_reloc_base methods.
 513
 514 // Adjust the output section.
 515
 516 template<int sh_type, bool dynamic, int size, bool big_endian>
 517 void
 518 Output_data_reloc_base<sh_type, dynamic, size, big_endian>
 519     ::do_adjust_output_section(Output_section* os)
 520 {
 521   if (sh_type == elfcpp::SHT_REL)
 522     os->set_entsize(elfcpp::Elf_sizes<size>::rel_size);
 523   else if (sh_type == elfcpp::SHT_RELA)
 524     os->set_entsize(elfcpp::Elf_sizes<size>::rela_size);
 525   else
 526     gold_unreachable();
 527   if (dynamic)
 528     os->set_should_link_to_dynsym();
 529   else
 530     os->set_should_link_to_symtab();
 531 }
 532
 533 // Write out relocation data.
 534
 535 template<int sh_type, bool dynamic, int size, bool big_endian>
 536 void
 537 Output_data_reloc_base<sh_type, dynamic, size, big_endian>::do_write(
 538     Output_file* of)
 539 {
 540   const off_t off = this->offset();
 541   const off_t oview_size = this->data_size();
 542   unsigned char* const oview = of->get_output_view(off, oview_size);
 543
 544   unsigned char* pov = oview;
 545   for (typename Relocs::const_iterator p = this->relocs_.begin();
 546        p != this->relocs_.end();
 547        ++p)
 548     {
 549       p->write(pov);
 550       pov += reloc_size;
 551     }
 552
 553   gold_assert(pov - oview == oview_size);
 554
 555   of->write_output_view(off, oview_size, oview);
 556
 557   // We no longer need the relocation entries.
 558   this->relocs_.clear();
 559 }
 560
 561 // Output_data_got::Got_entry methods.
 562
 563 // Write out the entry.
 564
 565 template<int size, bool big_endian>
 566 void
 567 Output_data_got<size, big_endian>::Got_entry::write(
 568     const General_options* options,
 569     unsigned char* pov) const
 570 {
 571   Valtype val = 0;
 572
 573   switch (this->local_sym_index_)
 574     {
 575     case GSYM_CODE:
 576       {
 577         Symbol* gsym = this->u_.gsym;
 578
 579         // If the symbol is resolved locally, we need to write out its
 580         // value.  Otherwise we just write zero.  The target code is
 581         // responsible for creating a relocation entry to fill in the
 582         // value at runtime.
 583         if (gsym->final_value_is_known(options))
 584           {
 585             Sized_symbol<size>* sgsym;
 586             // This cast is a bit ugly.  We don't want to put a
 587             // virtual method in Symbol, because we want Symbol to be
 588             // as small as possible.
 589             sgsym = static_cast<Sized_symbol<size>*>(gsym);
 590             val = sgsym->value();
 591           }
 592       }
 593       break;
 594
 595     case CONSTANT_CODE:
 596       val = this->u_.constant;
 597       break;
 598
 599     default:
 600       gold_unreachable();
 601     }
 602
 603   elfcpp::Swap<size, big_endian>::writeval(pov, val);
 604 }
 605
 606 // Output_data_got methods.
 607
 608 // Add an entry for a global symbol to the GOT.  This returns true if
 609 // this is a new GOT entry, false if the symbol already had a GOT
 610 // entry.
 611
 612 template<int size, bool big_endian>
 613 bool
 614 Output_data_got<size, big_endian>::add_global(Symbol* gsym)
 615 {
 616   if (gsym->has_got_offset())
 617     return false;
 618
 619   this->entries_.push_back(Got_entry(gsym));
 620   this->set_got_size();
 621   gsym->set_got_offset(this->last_got_offset());
 622   return true;
 623 }
 624
 625 // Write out the GOT.
 626
 627 template<int size, bool big_endian>
 628 void
 629 Output_data_got<size, big_endian>::do_write(Output_file* of)
 630 {
 631   const int add = size / 8;
 632
 633   const off_t off = this->offset();
 634   const off_t oview_size = this->data_size();
 635   unsigned char* const oview = of->get_output_view(off, oview_size);
 636
 637   unsigned char* pov = oview;
 638   for (typename Got_entries::const_iterator p = this->entries_.begin();
 639        p != this->entries_.end();
 640        ++p)
 641     {
 642       p->write(this->options_, pov);
 643       pov += add;
 644     }
 645
 646   gold_assert(pov - oview == oview_size);
 647
 648   of->write_output_view(off, oview_size, oview);
 649
 650   // We no longer need the GOT entries.
 651   this->entries_.clear();
 652 }
 653
 654 // Output_data_dynamic::Dynamic_entry methods.
 655
 656 // Write out the entry.
 657
 658 template<int size, bool big_endian>
 659 void
 660 Output_data_dynamic::Dynamic_entry::write(
 661     unsigned char* pov,
 662     const Stringpool* pool
 663     ACCEPT_SIZE_ENDIAN) const
 664 {
 665   typename elfcpp::Elf_types<size>::Elf_WXword val;
 666   switch (this->classification_)
 667     {
 668     case DYNAMIC_NUMBER:
 669       val = this->u_.val;
 670       break;
 671
 672     case DYNAMIC_SECTION_ADDRESS:
 673       val = this->u_.od->address();
 674       break;
 675
 676     case DYNAMIC_SECTION_SIZE:
 677       val = this->u_.od->data_size();
 678       break;
 679
 680     case DYNAMIC_SYMBOL:
 681       {
 682         const Sized_symbol<size>* s =
 683           static_cast<const Sized_symbol<size>*>(this->u_.sym);
 684         val = s->value();
 685       }
 686       break;
 687
 688     case DYNAMIC_STRING:
 689       val = pool->get_offset(this->u_.str);
 690       break;
 691
 692     default:
 693       gold_unreachable();
 694     }
 695
 696   elfcpp::Dyn_write<size, big_endian> dw(pov);
 697   dw.put_d_tag(this->tag_);
 698   dw.put_d_val(val);
 699 }
 700
 701 // Output_data_dynamic methods.
 702
 703 // Adjust the output section to set the entry size.
 704
 705 void
 706 Output_data_dynamic::do_adjust_output_section(Output_section* os)
 707 {
 708   if (this->target_->get_size() == 32)
 709     os->set_entsize(elfcpp::Elf_sizes<32>::dyn_size);
 710   else if (this->target_->get_size() == 64)
 711     os->set_entsize(elfcpp::Elf_sizes<64>::dyn_size);
 712   else
 713     gold_unreachable();
 714 }
 715
 716 // Set the final data size.
 717
 718 void
 719 Output_data_dynamic::do_set_address(uint64_t, off_t)
 720 {
 721   // Add the terminating entry.
 722   this->add_constant(elfcpp::DT_NULL, 0);
 723
 724   int dyn_size;
 725   if (this->target_->get_size() == 32)
 726     dyn_size = elfcpp::Elf_sizes<32>::dyn_size;
 727   else if (this->target_->get_size() == 64)
 728     dyn_size = elfcpp::Elf_sizes<64>::dyn_size;
 729   else
 730     gold_unreachable();
 731   this->set_data_size(this->entries_.size() * dyn_size);
 732 }
 733
 734 // Write out the dynamic entries.
 735
 736 void
 737 Output_data_dynamic::do_write(Output_file* of)
 738 {
 739   if (this->target_->get_size() == 32)
 740     {
 741       if (this->target_->is_big_endian())
 742         this->sized_write<32, true>(of);
 743       else
 744         this->sized_write<32, false>(of);
 745     }
 746   else if (this->target_->get_size() == 64)
 747     {
 748       if (this->target_->is_big_endian())
 749         this->sized_write<64, true>(of);
 750       else
 751         this->sized_write<64, false>(of);
 752     }
 753   else
 754     gold_unreachable();
 755 }
 756
 757 template<int size, bool big_endian>
 758 void
 759 Output_data_dynamic::sized_write(Output_file* of)
 760 {
 761   const int dyn_size = elfcpp::Elf_sizes<size>::dyn_size;
 762
 763   const off_t offset = this->offset();
 764   const off_t oview_size = this->data_size();
 765   unsigned char* const oview = of->get_output_view(offset, oview_size);
 766
 767   unsigned char* pov = oview;
 768   for (typename Dynamic_entries::const_iterator p = this->entries_.begin();
 769        p != this->entries_.end();
 770        ++p)
 771     {
 772       p->write SELECT_SIZE_ENDIAN_NAME(size, big_endian)(
 773           pov, this->pool_ SELECT_SIZE_ENDIAN(size, big_endian));
 774       pov += dyn_size;
 775     }
 776
 777   gold_assert(pov - oview == oview_size);
 778
 779   of->write_output_view(offset, oview_size, oview);
 780
 781   // We no longer need the dynamic entries.
 782   this->entries_.clear();
 783 }
 784
 785 // Output_section::Input_section methods.
 786
 787 // Return the data size.  For an input section we store the size here.
 788 // For an Output_section_data, we have to ask it for the size.
 789
 790 off_t
 791 Output_section::Input_section::data_size() const
 792 {
 793   if (this->is_input_section())
 794     return this->u1_.data_size;
 795   else
 796     return this->u2_.posd->data_size();
 797 }
 798
 799 // Set the address and file offset.
 800
 801 void
 802 Output_section::Input_section::set_address(uint64_t addr, off_t off,
 803                                            off_t secoff)
 804 {
 805   if (this->is_input_section())
 806     this->u2_.object->set_section_offset(this->shndx_, off - secoff);
 807   else
 808     this->u2_.posd->set_address(addr, off);
 809 }
 810
 811 // Try to turn an input address into an output address.
 812
 813 bool
 814 Output_section::Input_section::output_address(const Relobj* object,
 815                                               unsigned int shndx,
 816                                               off_t offset,
 817                                               uint64_t output_section_address,
 818                                               uint64_t *poutput) const
 819 {
 820   if (!this->is_input_section())
 821     return this->u2_.posd->output_address(object, shndx, offset,
 822                                           output_section_address, poutput);
 823   else
 824     {
 825       if (this->u2_.object != object)
 826         return false;
 827       off_t output_offset;
 828       Output_section* os = object->output_section(shndx, &output_offset);
 829       gold_assert(os != NULL);
 830       *poutput = output_section_address + output_offset + offset;
 831       return true;
 832     }
 833 }
 834
 835 // Write out the data.  We don't have to do anything for an input
 836 // section--they are handled via Object::relocate--but this is where
 837 // we write out the data for an Output_section_data.
 838
 839 void
 840 Output_section::Input_section::write(Output_file* of)
 841 {
 842   if (!this->is_input_section())
 843     this->u2_.posd->write(of);
 844 }
 845
 846 // Output_section methods.
 847
 848 // Construct an Output_section.  NAME will point into a Stringpool.
 849
 850 Output_section::Output_section(const char* name, elfcpp::Elf_Word type,
 851                                elfcpp::Elf_Xword flags)
 852   : name_(name),
 853     addralign_(0),
 854     entsize_(0),
 855     link_section_(NULL),
 856     link_(0),
 857     info_section_(NULL),
 858     info_(0),
 859     type_(type),
 860     flags_(flags),
 861     out_shndx_(0),
 862     symtab_index_(0),
 863     dynsym_index_(0),
 864     input_sections_(),
 865     first_input_offset_(0),
 866     fills_(),
 867     needs_symtab_index_(false),
 868     needs_dynsym_index_(false),
 869     should_link_to_symtab_(false),
 870     should_link_to_dynsym_(false)
 871 {
 872 }
 873
 874 Output_section::~Output_section()
 875 {
 876 }
 877
 878 // Set the entry size.
 879
 880 void
 881 Output_section::set_entsize(uint64_t v)
 882 {
 883   if (this->entsize_ == 0)
 884     this->entsize_ = v;
 885   else
 886     gold_assert(this->entsize_ == v);
 887 }
 888
 889 // Add the input section SHNDX, with header SHDR, named SECNAME, in
 890 // OBJECT, to the Output_section.  Return the offset of the input
 891 // section within the output section.  We don't always keep track of
 892 // input sections for an Output_section.  Instead, each Object keeps
 893 // track of the Output_section for each of its input sections.
 894
 895 template<int size, bool big_endian>
 896 off_t
 897 Output_section::add_input_section(Relobj* object, unsigned int shndx,
 898                                   const char* secname,
 899                                   const elfcpp::Shdr<size, big_endian>& shdr)
 900 {
 901   elfcpp::Elf_Xword addralign = shdr.get_sh_addralign();
 902   if ((addralign & (addralign - 1)) != 0)
 903     {
 904       fprintf(stderr, _("%s: %s: invalid alignment %lu for section \"%s\"\n"),
 905               program_name, object->name().c_str(),
 906               static_cast<unsigned long>(addralign), secname);
 907       gold_exit(false);
 908     }
 909
 910   if (addralign > this->addralign_)
 911     this->addralign_ = addralign;
 912
 913   // If this is a SHF_MERGE section, we pass all the input sections to
 914   // a Output_data_merge.
 915   if ((shdr.get_sh_flags() & elfcpp::SHF_MERGE) != 0)
 916     {
 917       if (this->add_merge_input_section(object, shndx, shdr.get_sh_flags(),
 918                                         shdr.get_sh_entsize(),
 919                                         addralign))
 920         {
 921           // Tell the relocation routines that they need to call the
 922           // output_address method to determine the final address.
 923           return -1;
 924         }
 925     }
 926
 927   off_t offset_in_section = this->data_size();
 928   off_t aligned_offset_in_section = align_address(offset_in_section,
 929                                                   addralign);
 930
 931   if (aligned_offset_in_section > offset_in_section
 932       && (shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0
 933       && object->target()->has_code_fill())
 934     {
 935       // We need to add some fill data.  Using fill_list_ when
 936       // possible is an optimization, since we will often have fill
 937       // sections without input sections.
 938       off_t fill_len = aligned_offset_in_section - offset_in_section;
 939       if (this->input_sections_.empty())
 940         this->fills_.push_back(Fill(offset_in_section, fill_len));
 941       else
 942         {
 943           // FIXME: When relaxing, the size needs to adjust to
 944           // maintain a constant alignment.
 945           std::string fill_data(object->target()->code_fill(fill_len));
 946           Output_data_const* odc = new Output_data_const(fill_data, 1);
 947           this->input_sections_.push_back(Input_section(odc));
 948         }
 949     }
 950
 951   this->set_data_size(aligned_offset_in_section + shdr.get_sh_size());
 952
 953   // We need to keep track of this section if we are already keeping
 954   // track of sections, or if we are relaxing.  FIXME: Add test for
 955   // relaxing.
 956   if (!this->input_sections_.empty())
 957     this->input_sections_.push_back(Input_section(object, shndx,
 958                                                   shdr.get_sh_size(),
 959                                                   addralign));
 960
 961   return aligned_offset_in_section;
 962 }
 963
 964 // Add arbitrary data to an output section.
 965
 966 void
 967 Output_section::add_output_section_data(Output_section_data* posd)
 968 {
 969   Input_section inp(posd);
 970   this->add_output_section_data(&inp);
 971 }
 972
 973 // Add arbitrary data to an output section by Input_section.
 974
 975 void
 976 Output_section::add_output_section_data(Input_section* inp)
 977 {
 978   if (this->input_sections_.empty())
 979     this->first_input_offset_ = this->data_size();
 980
 981   this->input_sections_.push_back(*inp);
 982
 983   uint64_t addralign = inp->addralign();
 984   if (addralign > this->addralign_)
 985     this->addralign_ = addralign;
 986
 987   inp->set_output_section(this);
 988 }
 989
 990 // Add a merge section to an output section.
 991
 992 void
 993 Output_section::add_output_merge_section(Output_section_data* posd,
 994                                          bool is_string, uint64_t entsize)
 995 {
 996   Input_section inp(posd, is_string, entsize);
 997   this->add_output_section_data(&inp);
 998 }
 999
1000 // Add an input section to a SHF_MERGE section.
1001
1002 bool
1003 Output_section::add_merge_input_section(Relobj* object, unsigned int shndx,
1004                                         uint64_t flags, uint64_t entsize,
1005                                         uint64_t addralign)
1006 {
1007   // We only merge constants if the alignment is not more than the
1008   // entry size.  This could be handled, but it's unusual.
1009   if (addralign > entsize)
1010     return false;
1011
1012   bool is_string = (flags & elfcpp::SHF_STRINGS) != 0;
1013   Input_section_list::iterator p;
1014   for (p = this->input_sections_.begin();
1015        p != this->input_sections_.end();
1016        ++p)
1017     if (p->is_merge_section(is_string, entsize))
1018       break;
1019
1020   // We handle the actual constant merging in Output_merge_data or
1021   // Output_merge_string_data.
1022   if (p != this->input_sections_.end())
1023     p->add_input_section(object, shndx);
1024   else
1025     {
1026       Output_section_data* posd;
1027       if (!is_string)
1028         posd = new Output_merge_data(entsize);
1029       else if (entsize == 1)
1030         posd = new Output_merge_string<char>();
1031       else if (entsize == 2)
1032         posd = new Output_merge_string<uint16_t>();
1033       else if (entsize == 4)
1034         posd = new Output_merge_string<uint32_t>();
1035       else
1036         return false;
1037
1038       this->add_output_merge_section(posd, is_string, entsize);
1039       posd->add_input_section(object, shndx);
1040     }
1041
1042   return true;
1043 }
1044
1045 // Return the output virtual address of OFFSET relative to the start
1046 // of input section SHNDX in object OBJECT.
1047
1048 uint64_t
1049 Output_section::output_address(const Relobj* object, unsigned int shndx,
1050                                off_t offset) const
1051 {
1052   uint64_t addr = this->address() + this->first_input_offset_;
1053   for (Input_section_list::const_iterator p = this->input_sections_.begin();
1054        p != this->input_sections_.end();
1055        ++p)
1056     {
1057       addr = align_address(addr, p->addralign());
1058       uint64_t output;
1059       if (p->output_address(object, shndx, offset, addr, &output))
1060         return output;
1061       addr += p->data_size();
1062     }
1063
1064   // If we get here, it means that we don't know the mapping for this
1065   // input section.  This might happen in principle if
1066   // add_input_section were called before add_output_section_data.
1067   // But it should never actually happen.
1068
1069   gold_unreachable();
1070 }
1071
1072 // Set the address of an Output_section.  This is where we handle
1073 // setting the addresses of any Output_section_data objects.
1074
1075 void
1076 Output_section::do_set_address(uint64_t address, off_t startoff)
1077 {
1078   if (this->input_sections_.empty())
1079     return;
1080
1081   off_t off = startoff + this->first_input_offset_;
1082   for (Input_section_list::iterator p = this->input_sections_.begin();
1083        p != this->input_sections_.end();
1084        ++p)
1085     {
1086       off = align_address(off, p->addralign());
1087       p->set_address(address + (off - startoff), off, startoff);
1088       off += p->data_size();
1089     }
1090
1091   this->set_data_size(off - startoff);
1092 }
1093
1094 // Write the section header to *OSHDR.
1095
1096 template<int size, bool big_endian>
1097 void
1098 Output_section::write_header(const Layout* layout,
1099                              const Stringpool* secnamepool,
1100                              elfcpp::Shdr_write<size, big_endian>* oshdr) const
1101 {
1102   oshdr->put_sh_name(secnamepool->get_offset(this->name_));
1103   oshdr->put_sh_type(this->type_);
1104   oshdr->put_sh_flags(this->flags_);
1105   oshdr->put_sh_addr(this->address());
1106   oshdr->put_sh_offset(this->offset());
1107   oshdr->put_sh_size(this->data_size());
1108   if (this->link_section_ != NULL)
1109     oshdr->put_sh_link(this->link_section_->out_shndx());
1110   else if (this->should_link_to_symtab_)
1111     oshdr->put_sh_link(layout->symtab_section()->out_shndx());
1112   else if (this->should_link_to_dynsym_)
1113     oshdr->put_sh_link(layout->dynsym_section()->out_shndx());
1114   else
1115     oshdr->put_sh_link(this->link_);
1116   if (this->info_section_ != NULL)
1117     oshdr->put_sh_info(this->info_section_->out_shndx());
1118   else
1119     oshdr->put_sh_info(this->info_);
1120   oshdr->put_sh_addralign(this->addralign_);
1121   oshdr->put_sh_entsize(this->entsize_);
1122 }
1123
1124 // Write out the data.  For input sections the data is written out by
1125 // Object::relocate, but we have to handle Output_section_data objects
1126 // here.
1127
1128 void
1129 Output_section::do_write(Output_file* of)
1130 {
1131   off_t output_section_file_offset = this->offset();
1132   for (Fill_list::iterator p = this->fills_.begin();
1133        p != this->fills_.end();
1134        ++p)
1135     {
1136       std::string fill_data(of->target()->code_fill(p->length()));
1137       of->write(output_section_file_offset + p->section_offset(),
1138                 fill_data.data(), fill_data.size());
1139     }
1140
1141   for (Input_section_list::iterator p = this->input_sections_.begin();
1142        p != this->input_sections_.end();
1143        ++p)
1144     p->write(of);
1145 }
1146
1147 // Output segment methods.
1148
1149 Output_segment::Output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags)
1150   : output_data_(),
1151     output_bss_(),
1152     vaddr_(0),
1153     paddr_(0),
1154     memsz_(0),
1155     align_(0),
1156     offset_(0),
1157     filesz_(0),
1158     type_(type),
1159     flags_(flags),
1160     is_align_known_(false)
1161 {
1162 }
1163
1164 // Add an Output_section to an Output_segment.
1165
1166 void
1167 Output_segment::add_output_section(Output_section* os,
1168                                    elfcpp::Elf_Word seg_flags,
1169                                    bool front)
1170 {
1171   gold_assert((os->flags() & elfcpp::SHF_ALLOC) != 0);
1172   gold_assert(!this->is_align_known_);
1173
1174   // Update the segment flags.
1175   this->flags_ |= seg_flags;
1176
1177   Output_segment::Output_data_list* pdl;
1178   if (os->type() == elfcpp::SHT_NOBITS)
1179     pdl = &this->output_bss_;
1180   else
1181     pdl = &this->output_data_;
1182
1183   // So that PT_NOTE segments will work correctly, we need to ensure
1184   // that all SHT_NOTE sections are adjacent.  This will normally
1185   // happen automatically, because all the SHT_NOTE input sections
1186   // will wind up in the same output section.  However, it is possible
1187   // for multiple SHT_NOTE input sections to have different section
1188   // flags, and thus be in different output sections, but for the
1189   // different section flags to map into the same segment flags and
1190   // thus the same output segment.
1191
1192   // Note that while there may be many input sections in an output
1193   // section, there are normally only a few output sections in an
1194   // output segment.  This loop is expected to be fast.
1195
1196   if (os->type() == elfcpp::SHT_NOTE && !pdl->empty())
1197     {
1198       Output_segment::Output_data_list::iterator p = pdl->end();
1199       do
1200         {
1201           --p;
1202           if ((*p)->is_section_type(elfcpp::SHT_NOTE))
1203             {
1204               // We don't worry about the FRONT parameter.
1205               ++p;
1206               pdl->insert(p, os);
1207               return;
1208             }
1209         }
1210       while (p != pdl->begin());
1211     }
1212
1213   // Similarly, so that PT_TLS segments will work, we need to group
1214   // SHF_TLS sections.  An SHF_TLS/SHT_NOBITS section is a special
1215   // case: we group the SHF_TLS/SHT_NOBITS sections right after the
1216   // SHF_TLS/SHT_PROGBITS sections.  This lets us set up PT_TLS
1217   // correctly.
1218   if ((os->flags() & elfcpp::SHF_TLS) != 0 && !this->output_data_.empty())
1219     {
1220       pdl = &this->output_data_;
1221       bool nobits = os->type() == elfcpp::SHT_NOBITS;
1222       bool sawtls = false;
1223       Output_segment::Output_data_list::iterator p = pdl->end();
1224       do
1225         {
1226           --p;
1227           bool insert;
1228           if ((*p)->is_section_flag_set(elfcpp::SHF_TLS))
1229             {
1230               sawtls = true;
1231               // Put a NOBITS section after the first TLS section.
1232               // But a PROGBITS section after the first TLS/PROGBITS
1233               // section.
1234               insert = nobits || !(*p)->is_section_type(elfcpp::SHT_NOBITS);
1235             }
1236           else
1237             {
1238               // If we've gone past the TLS sections, but we've seen a
1239               // TLS section, then we need to insert this section now.
1240               insert = sawtls;
1241             }
1242
1243           if (insert)
1244             {
1245               // We don't worry about the FRONT parameter.
1246               ++p;
1247               pdl->insert(p, os);
1248               return;
1249             }
1250         }
1251       while (p != pdl->begin());
1252
1253       // There are no TLS sections yet; put this one at the requested
1254       // location in the section list.
1255     }
1256
1257   if (front)
1258     pdl->push_front(os);
1259   else
1260     pdl->push_back(os);
1261 }
1262
1263 // Add an Output_data (which is not an Output_section) to the start of
1264 // a segment.
1265
1266 void
1267 Output_segment::add_initial_output_data(Output_data* od)
1268 {
1269   gold_assert(!this->is_align_known_);
1270   this->output_data_.push_front(od);
1271 }
1272
1273 // Return the maximum alignment of the Output_data in Output_segment.
1274 // Once we compute this, we prohibit new sections from being added.
1275
1276 uint64_t
1277 Output_segment::addralign()
1278 {
1279   if (!this->is_align_known_)
1280     {
1281       uint64_t addralign;
1282
1283       addralign = Output_segment::maximum_alignment(&this->output_data_);
1284       if (addralign > this->align_)
1285         this->align_ = addralign;
1286
1287       addralign = Output_segment::maximum_alignment(&this->output_bss_);
1288       if (addralign > this->align_)
1289         this->align_ = addralign;
1290
1291       this->is_align_known_ = true;
1292     }
1293
1294   return this->align_;
1295 }
1296
1297 // Return the maximum alignment of a list of Output_data.
1298
1299 uint64_t
1300 Output_segment::maximum_alignment(const Output_data_list* pdl)
1301 {
1302   uint64_t ret = 0;
1303   for (Output_data_list::const_iterator p = pdl->begin();
1304        p != pdl->end();
1305        ++p)
1306     {
1307       uint64_t addralign = (*p)->addralign();
1308       if (addralign > ret)
1309         ret = addralign;
1310     }
1311   return ret;
1312 }
1313
1314 // Set the section addresses for an Output_segment.  ADDR is the
1315 // address and *POFF is the file offset.  Set the section indexes
1316 // starting with *PSHNDX.  Return the address of the immediately
1317 // following segment.  Update *POFF and *PSHNDX.
1318
1319 uint64_t
1320 Output_segment::set_section_addresses(uint64_t addr, off_t* poff,
1321                                       unsigned int* pshndx)
1322 {
1323   gold_assert(this->type_ == elfcpp::PT_LOAD);
1324
1325   this->vaddr_ = addr;
1326   this->paddr_ = addr;
1327
1328   off_t orig_off = *poff;
1329   this->offset_ = orig_off;
1330
1331   *poff = align_address(*poff, this->addralign());
1332
1333   addr = this->set_section_list_addresses(&this->output_data_, addr, poff,
1334                                           pshndx);
1335   this->filesz_ = *poff - orig_off;
1336
1337   off_t off = *poff;
1338
1339   uint64_t ret = this->set_section_list_addresses(&this->output_bss_, addr,
1340                                                   poff, pshndx);
1341   this->memsz_ = *poff - orig_off;
1342
1343   // Ignore the file offset adjustments made by the BSS Output_data
1344   // objects.
1345   *poff = off;
1346
1347   return ret;
1348 }
1349
1350 // Set the addresses and file offsets in a list of Output_data
1351 // structures.
1352
1353 uint64_t
1354 Output_segment::set_section_list_addresses(Output_data_list* pdl,
1355                                            uint64_t addr, off_t* poff,
1356                                            unsigned int* pshndx)
1357 {
1358   off_t startoff = *poff;
1359
1360   off_t off = startoff;
1361   for (Output_data_list::iterator p = pdl->begin();
1362        p != pdl->end();
1363        ++p)
1364     {
1365       off = align_address(off, (*p)->addralign());
1366       (*p)->set_address(addr + (off - startoff), off);
1367
1368       // Unless this is a PT_TLS segment, we want to ignore the size
1369       // of a SHF_TLS/SHT_NOBITS section.  Such a section does not
1370       // affect the size of a PT_LOAD segment.
1371       if (this->type_ == elfcpp::PT_TLS
1372           || !(*p)->is_section_flag_set(elfcpp::SHF_TLS)
1373           || !(*p)->is_section_type(elfcpp::SHT_NOBITS))
1374         off += (*p)->data_size();
1375
1376       if ((*p)->is_section())
1377         {
1378           (*p)->set_out_shndx(*pshndx);
1379           ++*pshndx;
1380         }
1381     }
1382
1383   *poff = off;
1384   return addr + (off - startoff);
1385 }
1386
1387 // For a non-PT_LOAD segment, set the offset from the sections, if
1388 // any.
1389
1390 void
1391 Output_segment::set_offset()
1392 {
1393   gold_assert(this->type_ != elfcpp::PT_LOAD);
1394
1395   if (this->output_data_.empty() && this->output_bss_.empty())
1396     {
1397       this->vaddr_ = 0;
1398       this->paddr_ = 0;
1399       this->memsz_ = 0;
1400       this->align_ = 0;
1401       this->offset_ = 0;
1402       this->filesz_ = 0;
1403       return;
1404     }
1405
1406   const Output_data* first;
1407   if (this->output_data_.empty())
1408     first = this->output_bss_.front();
1409   else
1410     first = this->output_data_.front();
1411   this->vaddr_ = first->address();
1412   this->paddr_ = this->vaddr_;
1413   this->offset_ = first->offset();
1414
1415   if (this->output_data_.empty())
1416     this->filesz_ = 0;
1417   else
1418     {
1419       const Output_data* last_data = this->output_data_.back();
1420       this->filesz_ = (last_data->address()
1421                        + last_data->data_size()
1422                        - this->vaddr_);
1423     }
1424
1425   const Output_data* last;
1426   if (this->output_bss_.empty())
1427     last = this->output_data_.back();
1428   else
1429     last = this->output_bss_.back();
1430   this->memsz_ = (last->address()
1431                   + last->data_size()
1432                   - this->vaddr_);
1433 }
1434
1435 // Return the number of Output_sections in an Output_segment.
1436
1437 unsigned int
1438 Output_segment::output_section_count() const
1439 {
1440   return (this->output_section_count_list(&this->output_data_)
1441           + this->output_section_count_list(&this->output_bss_));
1442 }
1443
1444 // Return the number of Output_sections in an Output_data_list.
1445
1446 unsigned int
1447 Output_segment::output_section_count_list(const Output_data_list* pdl) const
1448 {
1449   unsigned int count = 0;
1450   for (Output_data_list::const_iterator p = pdl->begin();
1451        p != pdl->end();
1452        ++p)
1453     {
1454       if ((*p)->is_section())
1455         ++count;
1456     }
1457   return count;
1458 }
1459
1460 // Write the segment data into *OPHDR.
1461
1462 template<int size, bool big_endian>
1463 void
1464 Output_segment::write_header(elfcpp::Phdr_write<size, big_endian>* ophdr)
1465 {
1466   ophdr->put_p_type(this->type_);
1467   ophdr->put_p_offset(this->offset_);
1468   ophdr->put_p_vaddr(this->vaddr_);
1469   ophdr->put_p_paddr(this->paddr_);
1470   ophdr->put_p_filesz(this->filesz_);
1471   ophdr->put_p_memsz(this->memsz_);
1472   ophdr->put_p_flags(this->flags_);
1473   ophdr->put_p_align(this->addralign());
1474 }
1475
1476 // Write the section headers into V.
1477
1478 template<int size, bool big_endian>
1479 unsigned char*
1480 Output_segment::write_section_headers(const Layout* layout,
1481                                       const Stringpool* secnamepool,
1482                                       unsigned char* v,
1483                                       unsigned int *pshndx
1484                                       ACCEPT_SIZE_ENDIAN) const
1485 {
1486   // Every section that is attached to a segment must be attached to a
1487   // PT_LOAD segment, so we only write out section headers for PT_LOAD
1488   // segments.
1489   if (this->type_ != elfcpp::PT_LOAD)
1490     return v;
1491
1492   v = this->write_section_headers_list
1493       SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1494           layout, secnamepool, &this->output_data_, v, pshndx
1495           SELECT_SIZE_ENDIAN(size, big_endian));
1496   v = this->write_section_headers_list
1497       SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1498           layout, secnamepool, &this->output_bss_, v, pshndx
1499           SELECT_SIZE_ENDIAN(size, big_endian));
1500   return v;
1501 }
1502
1503 template<int size, bool big_endian>
1504 unsigned char*
1505 Output_segment::write_section_headers_list(const Layout* layout,
1506                                            const Stringpool* secnamepool,
1507                                            const Output_data_list* pdl,
1508                                            unsigned char* v,
1509                                            unsigned int* pshndx
1510                                            ACCEPT_SIZE_ENDIAN) const
1511 {
1512   const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
1513   for (Output_data_list::const_iterator p = pdl->begin();
1514        p != pdl->end();
1515        ++p)
1516     {
1517       if ((*p)->is_section())
1518         {
1519           const Output_section* ps = static_cast<const Output_section*>(*p);
1520           gold_assert(*pshndx == ps->out_shndx());
1521           elfcpp::Shdr_write<size, big_endian> oshdr(v);
1522           ps->write_header(layout, secnamepool, &oshdr);
1523           v += shdr_size;
1524           ++*pshndx;
1525         }
1526     }
1527   return v;
1528 }
1529
1530 // Output_file methods.
1531
1532 Output_file::Output_file(const General_options& options, Target* target)
1533   : options_(options),
1534     target_(target),
1535     name_(options.output_file_name()),
1536     o_(-1),
1537     file_size_(0),
1538     base_(NULL)
1539 {
1540 }
1541
1542 // Open the output file.
1543
1544 void
1545 Output_file::open(off_t file_size)
1546 {
1547   this->file_size_ = file_size;
1548
1549   int mode = this->options_.is_relocatable() ? 0666 : 0777;
1550   int o = ::open(this->name_, O_RDWR | O_CREAT | O_TRUNC, mode);
1551   if (o < 0)
1552     {
1553       fprintf(stderr, _("%s: %s: open: %s\n"),
1554               program_name, this->name_, strerror(errno));
1555       gold_exit(false);
1556     }
1557   this->o_ = o;
1558
1559   // Write out one byte to make the file the right size.
1560   if (::lseek(o, file_size - 1, SEEK_SET) < 0)
1561     {
1562       fprintf(stderr, _("%s: %s: lseek: %s\n"),
1563               program_name, this->name_, strerror(errno));
1564       gold_exit(false);
1565     }
1566   char b = 0;
1567   if (::write(o, &b, 1) != 1)
1568     {
1569       fprintf(stderr, _("%s: %s: write: %s\n"),
1570               program_name, this->name_, strerror(errno));
1571       gold_exit(false);
1572     }
1573
1574   // Map the file into memory.
1575   void* base = ::mmap(NULL, file_size, PROT_READ | PROT_WRITE,
1576                       MAP_SHARED, o, 0);
1577   if (base == MAP_FAILED)
1578     {
1579       fprintf(stderr, _("%s: %s: mmap: %s\n"),
1580               program_name, this->name_, strerror(errno));
1581       gold_exit(false);
1582     }
1583   this->base_ = static_cast<unsigned char*>(base);
1584 }
1585
1586 // Close the output file.
1587
1588 void
1589 Output_file::close()
1590 {
1591   if (::munmap(this->base_, this->file_size_) < 0)
1592     {
1593       fprintf(stderr, _("%s: %s: munmap: %s\n"),
1594               program_name, this->name_, strerror(errno));
1595       gold_exit(false);
1596     }
1597   this->base_ = NULL;
1598
1599   if (::close(this->o_) < 0)
1600     {
1601       fprintf(stderr, _("%s: %s: close: %s\n"),
1602               program_name, this->name_, strerror(errno));
1603       gold_exit(false);
1604     }
1605   this->o_ = -1;
1606 }
1607
1608 // Instantiate the templates we need.  We could use the configure
1609 // script to restrict this to only the ones for implemented targets.
1610
1611 #ifdef HAVE_TARGET_32_LITTLE
1612 template
1613 off_t
1614 Output_section::add_input_section<32, false>(
1615     Relobj* object,
1616     unsigned int shndx,
1617     const char* secname,
1618     const elfcpp::Shdr<32, false>& shdr);
1619 #endif
1620
1621 #ifdef HAVE_TARGET_32_BIG
1622 template
1623 off_t
1624 Output_section::add_input_section<32, true>(
1625     Relobj* object,
1626     unsigned int shndx,
1627     const char* secname,
1628     const elfcpp::Shdr<32, true>& shdr);
1629 #endif
1630
1631 #ifdef HAVE_TARGET_64_LITTLE
1632 template
1633 off_t
1634 Output_section::add_input_section<64, false>(
1635     Relobj* object,
1636     unsigned int shndx,
1637     const char* secname,
1638     const elfcpp::Shdr<64, false>& shdr);
1639 #endif
1640
1641 #ifdef HAVE_TARGET_64_BIG
1642 template
1643 off_t
1644 Output_section::add_input_section<64, true>(
1645     Relobj* object,
1646     unsigned int shndx,
1647     const char* secname,
1648     const elfcpp::Shdr<64, true>& shdr);
1649 #endif
1650
1651 #ifdef HAVE_TARGET_32_LITTLE
1652 template
1653 class Output_data_reloc<elfcpp::SHT_REL, false, 32, false>;
1654 #endif
1655
1656 #ifdef HAVE_TARGET_32_BIG
1657 template
1658 class Output_data_reloc<elfcpp::SHT_REL, false, 32, true>;
1659 #endif
1660
1661 #ifdef HAVE_TARGET_64_LITTLE
1662 template
1663 class Output_data_reloc<elfcpp::SHT_REL, false, 64, false>;
1664 #endif
1665
1666 #ifdef HAVE_TARGET_64_BIG
1667 template
1668 class Output_data_reloc<elfcpp::SHT_REL, false, 64, true>;
1669 #endif
1670
1671 #ifdef HAVE_TARGET_32_LITTLE
1672 template
1673 class Output_data_reloc<elfcpp::SHT_REL, true, 32, false>;
1674 #endif
1675
1676 #ifdef HAVE_TARGET_32_BIG
1677 template
1678 class Output_data_reloc<elfcpp::SHT_REL, true, 32, true>;
1679 #endif
1680
1681 #ifdef HAVE_TARGET_64_LITTLE
1682 template
1683 class Output_data_reloc<elfcpp::SHT_REL, true, 64, false>;
1684 #endif
1685
1686 #ifdef HAVE_TARGET_64_BIG
1687 template
1688 class Output_data_reloc<elfcpp::SHT_REL, true, 64, true>;
1689 #endif
1690
1691 #ifdef HAVE_TARGET_32_LITTLE
1692 template
1693 class Output_data_reloc<elfcpp::SHT_RELA, false, 32, false>;
1694 #endif
1695
1696 #ifdef HAVE_TARGET_32_BIG
1697 template
1698 class Output_data_reloc<elfcpp::SHT_RELA, false, 32, true>;
1699 #endif
1700
1701 #ifdef HAVE_TARGET_64_LITTLE
1702 template
1703 class Output_data_reloc<elfcpp::SHT_RELA, false, 64, false>;
1704 #endif
1705
1706 #ifdef HAVE_TARGET_64_BIG
1707 template
1708 class Output_data_reloc<elfcpp::SHT_RELA, false, 64, true>;
1709 #endif
1710
1711 #ifdef HAVE_TARGET_32_LITTLE
1712 template
1713 class Output_data_reloc<elfcpp::SHT_RELA, true, 32, false>;
1714 #endif
1715
1716 #ifdef HAVE_TARGET_32_BIG
1717 template
1718 class Output_data_reloc<elfcpp::SHT_RELA, true, 32, true>;
1719 #endif
1720
1721 #ifdef HAVE_TARGET_64_LITTLE
1722 template
1723 class Output_data_reloc<elfcpp::SHT_RELA, true, 64, false>;
1724 #endif
1725
1726 #ifdef HAVE_TARGET_64_BIG
1727 template
1728 class Output_data_reloc<elfcpp::SHT_RELA, true, 64, true>;
1729 #endif
1730
1731 #ifdef HAVE_TARGET_32_LITTLE
1732 template
1733 class Output_data_got<32, false>;
1734 #endif
1735
1736 #ifdef HAVE_TARGET_32_BIG
1737 template
1738 class Output_data_got<32, true>;
1739 #endif
1740
1741 #ifdef HAVE_TARGET_64_LITTLE
1742 template
1743 class Output_data_got<64, false>;
1744 #endif
1745
1746 #ifdef HAVE_TARGET_64_BIG
1747 template
1748 class Output_data_got<64, true>;
1749 #endif
1750
1751 } // End namespace gold.