gold/x86_64.cc

   1 // x86_64.cc -- x86_64 target support for gold.
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
   4 // Free Software Foundation, Inc.
   5 // Written by Ian Lance Taylor <iant@google.com>.
   6
   7 // This file is part of gold.
   8
   9 // This program is free software; you can redistribute it and/or modify
  10 // it under the terms of the GNU General Public License as published by
  11 // the Free Software Foundation; either version 3 of the License, or
  12 // (at your option) any later version.
  13
  14 // This program is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18
  19 // You should have received a copy of the GNU General Public License
  20 // along with this program; if not, write to the Free Software
  21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  22 // MA 02110-1301, USA.
  23
  24 #include "gold.h"
  25
  26 #include <cstring>
  27
  28 #include "elfcpp.h"
  29 #include "dwarf.h"
  30 #include "parameters.h"
  31 #include "reloc.h"
  32 #include "x86_64.h"
  33 #include "object.h"
  34 #include "symtab.h"
  35 #include "layout.h"
  36 #include "output.h"
  37 #include "copy-relocs.h"
  38 #include "target.h"
  39 #include "target-reloc.h"
  40 #include "target-select.h"
  41 #include "tls.h"
  42 #include "freebsd.h"
  43 #include "nacl.h"
  44 #include "gc.h"
  45 #include "icf.h"
  46
  47 namespace
  48 {
  49
  50 using namespace gold;
  51
  52 // A class to handle the PLT data.
  53 // This is an abstract base class that handles most of the linker details
  54 // but does not know the actual contents of PLT entries.  The derived
  55 // classes below fill in those details.
  56
  57 template<int size>
  58 class Output_data_plt_x86_64 : public Output_section_data
  59 {
  60  public:
  61   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
  62
  63   Output_data_plt_x86_64(Layout* layout, uint64_t addralign,
  64                          Output_data_got<64, false>* got,
  65                          Output_data_space* got_plt,
  66                          Output_data_space* got_irelative)
  67     : Output_section_data(addralign), layout_(layout), tlsdesc_rel_(NULL),
  68       irelative_rel_(NULL), got_(got), got_plt_(got_plt),
  69       got_irelative_(got_irelative), count_(0), irelative_count_(0),
  70       tlsdesc_got_offset_(-1U), free_list_()
  71   { this->init(layout); }
  72
  73   Output_data_plt_x86_64(Layout* layout, uint64_t plt_entry_size,
  74                          Output_data_got<64, false>* got,
  75                          Output_data_space* got_plt,
  76                          Output_data_space* got_irelative,
  77                          unsigned int plt_count)
  78     : Output_section_data((plt_count + 1) * plt_entry_size,
  79                           plt_entry_size, false),
  80       layout_(layout), tlsdesc_rel_(NULL), irelative_rel_(NULL), got_(got),
  81       got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count),
  82       irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
  83   {
  84     this->init(layout);
  85
  86     // Initialize the free list and reserve the first entry.
  87     this->free_list_.init((plt_count + 1) * plt_entry_size, false);
  88     this->free_list_.remove(0, plt_entry_size);
  89   }
  90
  91   // Initialize the PLT section.
  92   void
  93   init(Layout* layout);
  94
  95   // Add an entry to the PLT.
  96   void
  97   add_entry(Symbol_table*, Layout*, Symbol* gsym);
  98
  99   // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
 100   unsigned int
 101   add_local_ifunc_entry(Symbol_table* symtab, Layout*,
 102                         Sized_relobj_file<size, false>* relobj,
 103                         unsigned int local_sym_index);
 104
 105   // Add the relocation for a PLT entry.
 106   void
 107   add_relocation(Symbol_table*, Layout*, Symbol* gsym,
 108                  unsigned int got_offset);
 109
 110   // Add the reserved TLSDESC_PLT entry to the PLT.
 111   void
 112   reserve_tlsdesc_entry(unsigned int got_offset)
 113   { this->tlsdesc_got_offset_ = got_offset; }
 114
 115   // Return true if a TLSDESC_PLT entry has been reserved.
 116   bool
 117   has_tlsdesc_entry() const
 118   { return this->tlsdesc_got_offset_ != -1U; }
 119
 120   // Return the GOT offset for the reserved TLSDESC_PLT entry.
 121   unsigned int
 122   get_tlsdesc_got_offset() const
 123   { return this->tlsdesc_got_offset_; }
 124
 125   // Return the offset of the reserved TLSDESC_PLT entry.
 126   unsigned int
 127   get_tlsdesc_plt_offset() const
 128   {
 129     return ((this->count_ + this->irelative_count_ + 1)
 130             * this->get_plt_entry_size());
 131   }
 132
 133   // Return the .rela.plt section data.
 134   Reloc_section*
 135   rela_plt()
 136   { return this->rel_; }
 137
 138   // Return where the TLSDESC relocations should go.
 139   Reloc_section*
 140   rela_tlsdesc(Layout*);
 141
 142   // Return where the IRELATIVE relocations should go in the PLT
 143   // relocations.
 144   Reloc_section*
 145   rela_irelative(Symbol_table*, Layout*);
 146
 147   // Return whether we created a section for IRELATIVE relocations.
 148   bool
 149   has_irelative_section() const
 150   { return this->irelative_rel_ != NULL; }
 151
 152   // Return the number of PLT entries.
 153   unsigned int
 154   entry_count() const
 155   { return this->count_ + this->irelative_count_; }
 156
 157   // Return the offset of the first non-reserved PLT entry.
 158   unsigned int
 159   first_plt_entry_offset()
 160   { return this->get_plt_entry_size(); }
 161
 162   // Return the size of a PLT entry.
 163   unsigned int
 164   get_plt_entry_size() const
 165   { return this->do_get_plt_entry_size(); }
 166
 167   // Reserve a slot in the PLT for an existing symbol in an incremental update.
 168   void
 169   reserve_slot(unsigned int plt_index)
 170   {
 171     this->free_list_.remove((plt_index + 1) * this->get_plt_entry_size(),
 172                             (plt_index + 2) * this->get_plt_entry_size());
 173   }
 174
 175   // Return the PLT address to use for a global symbol.
 176   uint64_t
 177   address_for_global(const Symbol*);
 178
 179   // Return the PLT address to use for a local symbol.
 180   uint64_t
 181   address_for_local(const Relobj*, unsigned int symndx);
 182
 183   // Add .eh_frame information for the PLT.
 184   void
 185   add_eh_frame(Layout* layout)
 186   { this->do_add_eh_frame(layout); }
 187
 188  protected:
 189   // Fill in the first PLT entry.
 190   void
 191   fill_first_plt_entry(unsigned char* pov,
 192                        typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 193                        typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
 194   { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
 195
 196   // Fill in a normal PLT entry.  Returns the offset into the entry that
 197   // should be the initial GOT slot value.
 198   unsigned int
 199   fill_plt_entry(unsigned char* pov,
 200                  typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 201                  typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 202                  unsigned int got_offset,
 203                  unsigned int plt_offset,
 204                  unsigned int plt_index)
 205   {
 206     return this->do_fill_plt_entry(pov, got_address, plt_address,
 207                                    got_offset, plt_offset, plt_index);
 208   }
 209
 210   // Fill in the reserved TLSDESC PLT entry.
 211   void
 212   fill_tlsdesc_entry(unsigned char* pov,
 213                      typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 214                      typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 215                      typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 216                      unsigned int tlsdesc_got_offset,
 217                      unsigned int plt_offset)
 218   {
 219     this->do_fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
 220                                 tlsdesc_got_offset, plt_offset);
 221   }
 222
 223   virtual unsigned int
 224   do_get_plt_entry_size() const = 0;
 225
 226   virtual void
 227   do_fill_first_plt_entry(unsigned char* pov,
 228                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
 229                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr)
 230     = 0;
 231
 232   virtual unsigned int
 233   do_fill_plt_entry(unsigned char* pov,
 234                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 235                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 236                     unsigned int got_offset,
 237                     unsigned int plt_offset,
 238                     unsigned int plt_index) = 0;
 239
 240   virtual void
 241   do_fill_tlsdesc_entry(unsigned char* pov,
 242                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 243                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 244                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 245                         unsigned int tlsdesc_got_offset,
 246                         unsigned int plt_offset) = 0;
 247
 248   virtual void
 249   do_add_eh_frame(Layout* layout) = 0;
 250
 251   void
 252   do_adjust_output_section(Output_section* os);
 253
 254   // Write to a map file.
 255   void
 256   do_print_to_mapfile(Mapfile* mapfile) const
 257   { mapfile->print_output_data(this, _("** PLT")); }
 258
 259   // The CIE of the .eh_frame unwind information for the PLT.
 260   static const int plt_eh_frame_cie_size = 16;
 261   static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
 262
 263  private:
 264   // Set the final size.
 265   void
 266   set_final_data_size();
 267
 268   // Write out the PLT data.
 269   void
 270   do_write(Output_file*);
 271
 272   // A pointer to the Layout class, so that we can find the .dynamic
 273   // section when we write out the GOT PLT section.
 274   Layout* layout_;
 275   // The reloc section.
 276   Reloc_section* rel_;
 277   // The TLSDESC relocs, if necessary.  These must follow the regular
 278   // PLT relocs.
 279   Reloc_section* tlsdesc_rel_;
 280   // The IRELATIVE relocs, if necessary.  These must follow the
 281   // regular PLT relocations and the TLSDESC relocations.
 282   Reloc_section* irelative_rel_;
 283   // The .got section.
 284   Output_data_got<64, false>* got_;
 285   // The .got.plt section.
 286   Output_data_space* got_plt_;
 287   // The part of the .got.plt section used for IRELATIVE relocs.
 288   Output_data_space* got_irelative_;
 289   // The number of PLT entries.
 290   unsigned int count_;
 291   // Number of PLT entries with R_X86_64_IRELATIVE relocs.  These
 292   // follow the regular PLT entries.
 293   unsigned int irelative_count_;
 294   // Offset of the reserved TLSDESC_GOT entry when needed.
 295   unsigned int tlsdesc_got_offset_;
 296   // List of available regions within the section, for incremental
 297   // update links.
 298   Free_list free_list_;
 299 };
 300
 301 template<int size>
 302 class Output_data_plt_x86_64_standard : public Output_data_plt_x86_64<size>
 303 {
 304  public:
 305   Output_data_plt_x86_64_standard(Layout* layout,
 306                                   Output_data_got<64, false>* got,
 307                                   Output_data_space* got_plt,
 308                                   Output_data_space* got_irelative)
 309     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 310                                    got, got_plt, got_irelative)
 311   { }
 312
 313   Output_data_plt_x86_64_standard(Layout* layout,
 314                                   Output_data_got<64, false>* got,
 315                                   Output_data_space* got_plt,
 316                                   Output_data_space* got_irelative,
 317                                   unsigned int plt_count)
 318     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 319                                    got, got_plt, got_irelative,
 320                                    plt_count)
 321   { }
 322
 323  protected:
 324   virtual unsigned int
 325   do_get_plt_entry_size() const
 326   { return plt_entry_size; }
 327
 328   virtual void
 329   do_add_eh_frame(Layout* layout)
 330   {
 331     layout->add_eh_frame_for_plt(this,
 332                                  this->plt_eh_frame_cie,
 333                                  this->plt_eh_frame_cie_size,
 334                                  plt_eh_frame_fde,
 335                                  plt_eh_frame_fde_size);
 336   }
 337
 338   virtual void
 339   do_fill_first_plt_entry(unsigned char* pov,
 340                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
 341                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
 342
 343   virtual unsigned int
 344   do_fill_plt_entry(unsigned char* pov,
 345                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 346                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 347                     unsigned int got_offset,
 348                     unsigned int plt_offset,
 349                     unsigned int plt_index);
 350
 351   virtual void
 352   do_fill_tlsdesc_entry(unsigned char* pov,
 353                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 354                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 355                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 356                         unsigned int tlsdesc_got_offset,
 357                         unsigned int plt_offset);
 358
 359  private:
 360   // The size of an entry in the PLT.
 361   static const int plt_entry_size = 16;
 362
 363   // The first entry in the PLT.
 364   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
 365   // procedure linkage table for both programs and shared objects."
 366   static const unsigned char first_plt_entry[plt_entry_size];
 367
 368   // Other entries in the PLT for an executable.
 369   static const unsigned char plt_entry[plt_entry_size];
 370
 371   // The reserved TLSDESC entry in the PLT for an executable.
 372   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
 373
 374   // The .eh_frame unwind information for the PLT.
 375   static const int plt_eh_frame_fde_size = 32;
 376   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
 377 };
 378
 379 // The x86_64 target class.
 380 // See the ABI at
 381 //   http://www.x86-64.org/documentation/abi.pdf
 382 // TLS info comes from
 383 //   http://people.redhat.com/drepper/tls.pdf
 384 //   http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
 385
 386 template<int size>
 387 class Target_x86_64 : public Sized_target<size, false>
 388 {
 389  public:
 390   // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
 391   // uses only Elf64_Rela relocation entries with explicit addends."
 392   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
 393
 394   Target_x86_64(const Target::Target_info* info = &x86_64_info)
 395     : Sized_target<size, false>(info),
 396       got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
 397       got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
 398       rela_irelative_(NULL), copy_relocs_(elfcpp::R_X86_64_COPY),
 399       dynbss_(NULL), got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
 400       tls_base_symbol_defined_(false)
 401   { }
 402
 403   // Hook for a new output section.
 404   void
 405   do_new_output_section(Output_section*) const;
 406
 407   // Scan the relocations to look for symbol adjustments.
 408   void
 409   gc_process_relocs(Symbol_table* symtab,
 410                     Layout* layout,
 411                     Sized_relobj_file<size, false>* object,
 412                     unsigned int data_shndx,
 413                     unsigned int sh_type,
 414                     const unsigned char* prelocs,
 415                     size_t reloc_count,
 416                     Output_section* output_section,
 417                     bool needs_special_offset_handling,
 418                     size_t local_symbol_count,
 419                     const unsigned char* plocal_symbols);
 420
 421   // Scan the relocations to look for symbol adjustments.
 422   void
 423   scan_relocs(Symbol_table* symtab,
 424               Layout* layout,
 425               Sized_relobj_file<size, false>* object,
 426               unsigned int data_shndx,
 427               unsigned int sh_type,
 428               const unsigned char* prelocs,
 429               size_t reloc_count,
 430               Output_section* output_section,
 431               bool needs_special_offset_handling,
 432               size_t local_symbol_count,
 433               const unsigned char* plocal_symbols);
 434
 435   // Finalize the sections.
 436   void
 437   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
 438
 439   // Return the value to use for a dynamic which requires special
 440   // treatment.
 441   uint64_t
 442   do_dynsym_value(const Symbol*) const;
 443
 444   // Relocate a section.
 445   void
 446   relocate_section(const Relocate_info<size, false>*,
 447                    unsigned int sh_type,
 448                    const unsigned char* prelocs,
 449                    size_t reloc_count,
 450                    Output_section* output_section,
 451                    bool needs_special_offset_handling,
 452                    unsigned char* view,
 453                    typename elfcpp::Elf_types<size>::Elf_Addr view_address,
 454                    section_size_type view_size,
 455                    const Reloc_symbol_changes*);
 456
 457   // Scan the relocs during a relocatable link.
 458   void
 459   scan_relocatable_relocs(Symbol_table* symtab,
 460                           Layout* layout,
 461                           Sized_relobj_file<size, false>* object,
 462                           unsigned int data_shndx,
 463                           unsigned int sh_type,
 464                           const unsigned char* prelocs,
 465                           size_t reloc_count,
 466                           Output_section* output_section,
 467                           bool needs_special_offset_handling,
 468                           size_t local_symbol_count,
 469                           const unsigned char* plocal_symbols,
 470                           Relocatable_relocs*);
 471
 472   // Emit relocations for a section.
 473   void
 474   relocate_relocs(
 475       const Relocate_info<size, false>*,
 476       unsigned int sh_type,
 477       const unsigned char* prelocs,
 478       size_t reloc_count,
 479       Output_section* output_section,
 480       typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
 481       const Relocatable_relocs*,
 482       unsigned char* view,
 483       typename elfcpp::Elf_types<size>::Elf_Addr view_address,
 484       section_size_type view_size,
 485       unsigned char* reloc_view,
 486       section_size_type reloc_view_size);
 487
 488   // Return a string used to fill a code section with nops.
 489   std::string
 490   do_code_fill(section_size_type length) const;
 491
 492   // Return whether SYM is defined by the ABI.
 493   bool
 494   do_is_defined_by_abi(const Symbol* sym) const
 495   { return strcmp(sym->name(), "__tls_get_addr") == 0; }
 496
 497   // Return the symbol index to use for a target specific relocation.
 498   // The only target specific relocation is R_X86_64_TLSDESC for a
 499   // local symbol, which is an absolute reloc.
 500   unsigned int
 501   do_reloc_symbol_index(void*, unsigned int r_type) const
 502   {
 503     gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
 504     return 0;
 505   }
 506
 507   // Return the addend to use for a target specific relocation.
 508   uint64_t
 509   do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
 510
 511   // Return the PLT section.
 512   uint64_t
 513   do_plt_address_for_global(const Symbol* gsym) const
 514   { return this->plt_section()->address_for_global(gsym); }
 515
 516   uint64_t
 517   do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
 518   { return this->plt_section()->address_for_local(relobj, symndx); }
 519
 520   // This function should be defined in targets that can use relocation
 521   // types to determine (implemented in local_reloc_may_be_function_pointer
 522   // and global_reloc_may_be_function_pointer)
 523   // if a function's pointer is taken.  ICF uses this in safe mode to only
 524   // fold those functions whose pointer is defintely not taken.  For x86_64
 525   // pie binaries, safe ICF cannot be done by looking at relocation types.
 526   bool
 527   do_can_check_for_function_pointers() const
 528   { return !parameters->options().pie(); }
 529
 530   // Return the base for a DW_EH_PE_datarel encoding.
 531   uint64_t
 532   do_ehframe_datarel_base() const;
 533
 534   // Adjust -fsplit-stack code which calls non-split-stack code.
 535   void
 536   do_calls_non_split(Relobj* object, unsigned int shndx,
 537                      section_offset_type fnoffset, section_size_type fnsize,
 538                      unsigned char* view, section_size_type view_size,
 539                      std::string* from, std::string* to) const;
 540
 541   // Return the size of the GOT section.
 542   section_size_type
 543   got_size() const
 544   {
 545     gold_assert(this->got_ != NULL);
 546     return this->got_->data_size();
 547   }
 548
 549   // Return the number of entries in the GOT.
 550   unsigned int
 551   got_entry_count() const
 552   {
 553     if (this->got_ == NULL)
 554       return 0;
 555     return this->got_size() / 8;
 556   }
 557
 558   // Return the number of entries in the PLT.
 559   unsigned int
 560   plt_entry_count() const;
 561
 562   // Return the offset of the first non-reserved PLT entry.
 563   unsigned int
 564   first_plt_entry_offset() const;
 565
 566   // Return the size of each PLT entry.
 567   unsigned int
 568   plt_entry_size() const;
 569
 570   // Create the GOT section for an incremental update.
 571   Output_data_got_base*
 572   init_got_plt_for_update(Symbol_table* symtab,
 573                           Layout* layout,
 574                           unsigned int got_count,
 575                           unsigned int plt_count);
 576
 577   // Reserve a GOT entry for a local symbol, and regenerate any
 578   // necessary dynamic relocations.
 579   void
 580   reserve_local_got_entry(unsigned int got_index,
 581                           Sized_relobj<size, false>* obj,
 582                           unsigned int r_sym,
 583                           unsigned int got_type);
 584
 585   // Reserve a GOT entry for a global symbol, and regenerate any
 586   // necessary dynamic relocations.
 587   void
 588   reserve_global_got_entry(unsigned int got_index, Symbol* gsym,
 589                            unsigned int got_type);
 590
 591   // Register an existing PLT entry for a global symbol.
 592   void
 593   register_global_plt_entry(Symbol_table*, Layout*, unsigned int plt_index,
 594                             Symbol* gsym);
 595
 596   // Force a COPY relocation for a given symbol.
 597   void
 598   emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t);
 599
 600   // Apply an incremental relocation.
 601   void
 602   apply_relocation(const Relocate_info<size, false>* relinfo,
 603                    typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
 604                    unsigned int r_type,
 605                    typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
 606                    const Symbol* gsym,
 607                    unsigned char* view,
 608                    typename elfcpp::Elf_types<size>::Elf_Addr address,
 609                    section_size_type view_size);
 610
 611   // Add a new reloc argument, returning the index in the vector.
 612   size_t
 613   add_tlsdesc_info(Sized_relobj_file<size, false>* object, unsigned int r_sym)
 614   {
 615     this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
 616     return this->tlsdesc_reloc_info_.size() - 1;
 617   }
 618
 619   Output_data_plt_x86_64<size>*
 620   make_data_plt(Layout* layout,
 621                 Output_data_got<64, false>* got,
 622                 Output_data_space* got_plt,
 623                 Output_data_space* got_irelative)
 624   {
 625     return this->do_make_data_plt(layout, got, got_plt, got_irelative);
 626   }
 627
 628   Output_data_plt_x86_64<size>*
 629   make_data_plt(Layout* layout,
 630                 Output_data_got<64, false>* got,
 631                 Output_data_space* got_plt,
 632                 Output_data_space* got_irelative,
 633                 unsigned int plt_count)
 634   {
 635     return this->do_make_data_plt(layout, got, got_plt, got_irelative,
 636                                   plt_count);
 637   }
 638
 639   virtual Output_data_plt_x86_64<size>*
 640   do_make_data_plt(Layout* layout,
 641                    Output_data_got<64, false>* got,
 642                    Output_data_space* got_plt,
 643                    Output_data_space* got_irelative)
 644   {
 645     return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
 646                                                      got_irelative);
 647   }
 648
 649   virtual Output_data_plt_x86_64<size>*
 650   do_make_data_plt(Layout* layout,
 651                    Output_data_got<64, false>* got,
 652                    Output_data_space* got_plt,
 653                    Output_data_space* got_irelative,
 654                    unsigned int plt_count)
 655   {
 656     return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
 657                                                      got_irelative,
 658                                                      plt_count);
 659   }
 660
 661  private:
 662   // The class which scans relocations.
 663   class Scan
 664   {
 665   public:
 666     Scan()
 667       : issued_non_pic_error_(false)
 668     { }
 669
 670     static inline int
 671     get_reference_flags(unsigned int r_type);
 672
 673     inline void
 674     local(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
 675           Sized_relobj_file<size, false>* object,
 676           unsigned int data_shndx,
 677           Output_section* output_section,
 678           const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
 679           const elfcpp::Sym<size, false>& lsym,
 680           bool is_discarded);
 681
 682     inline void
 683     global(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
 684            Sized_relobj_file<size, false>* object,
 685            unsigned int data_shndx,
 686            Output_section* output_section,
 687            const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
 688            Symbol* gsym);
 689
 690     inline bool
 691     local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
 692                                         Target_x86_64* target,
 693                                         Sized_relobj_file<size, false>* object,
 694                                         unsigned int data_shndx,
 695                                         Output_section* output_section,
 696                                         const elfcpp::Rela<size, false>& reloc,
 697                                         unsigned int r_type,
 698                                         const elfcpp::Sym<size, false>& lsym);
 699
 700     inline bool
 701     global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
 702                                          Target_x86_64* target,
 703                                          Sized_relobj_file<size, false>* object,
 704                                          unsigned int data_shndx,
 705                                          Output_section* output_section,
 706                                          const elfcpp::Rela<size, false>& reloc,
 707                                          unsigned int r_type,
 708                                          Symbol* gsym);
 709
 710   private:
 711     static void
 712     unsupported_reloc_local(Sized_relobj_file<size, false>*,
 713                             unsigned int r_type);
 714
 715     static void
 716     unsupported_reloc_global(Sized_relobj_file<size, false>*,
 717                              unsigned int r_type, Symbol*);
 718
 719     void
 720     check_non_pic(Relobj*, unsigned int r_type, Symbol*);
 721
 722     inline bool
 723     possible_function_pointer_reloc(unsigned int r_type);
 724
 725     bool
 726     reloc_needs_plt_for_ifunc(Sized_relobj_file<size, false>*,
 727                               unsigned int r_type);
 728
 729     // Whether we have issued an error about a non-PIC compilation.
 730     bool issued_non_pic_error_;
 731   };
 732
 733   // The class which implements relocation.
 734   class Relocate
 735   {
 736    public:
 737     Relocate()
 738       : skip_call_tls_get_addr_(false)
 739     { }
 740
 741     ~Relocate()
 742     {
 743       if (this->skip_call_tls_get_addr_)
 744         {
 745           // FIXME: This needs to specify the location somehow.
 746           gold_error(_("missing expected TLS relocation"));
 747         }
 748     }
 749
 750     // Do a relocation.  Return false if the caller should not issue
 751     // any warnings about this relocation.
 752     inline bool
 753     relocate(const Relocate_info<size, false>*, Target_x86_64*,
 754              Output_section*,
 755              size_t relnum, const elfcpp::Rela<size, false>&,
 756              unsigned int r_type, const Sized_symbol<size>*,
 757              const Symbol_value<size>*,
 758              unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
 759              section_size_type);
 760
 761    private:
 762     // Do a TLS relocation.
 763     inline void
 764     relocate_tls(const Relocate_info<size, false>*, Target_x86_64*,
 765                  size_t relnum, const elfcpp::Rela<size, false>&,
 766                  unsigned int r_type, const Sized_symbol<size>*,
 767                  const Symbol_value<size>*,
 768                  unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
 769                  section_size_type);
 770
 771     // Do a TLS General-Dynamic to Initial-Exec transition.
 772     inline void
 773     tls_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
 774                  Output_segment* tls_segment,
 775                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 776                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 777                  unsigned char* view,
 778                  typename elfcpp::Elf_types<size>::Elf_Addr,
 779                  section_size_type view_size);
 780
 781     // Do a TLS General-Dynamic to Local-Exec transition.
 782     inline void
 783     tls_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
 784                  Output_segment* tls_segment,
 785                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 786                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 787                  unsigned char* view,
 788                  section_size_type view_size);
 789
 790     // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
 791     inline void
 792     tls_desc_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
 793                       Output_segment* tls_segment,
 794                       const elfcpp::Rela<size, false>&, unsigned int r_type,
 795                       typename elfcpp::Elf_types<size>::Elf_Addr value,
 796                       unsigned char* view,
 797                       typename elfcpp::Elf_types<size>::Elf_Addr,
 798                       section_size_type view_size);
 799
 800     // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
 801     inline void
 802     tls_desc_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
 803                       Output_segment* tls_segment,
 804                       const elfcpp::Rela<size, false>&, unsigned int r_type,
 805                       typename elfcpp::Elf_types<size>::Elf_Addr value,
 806                       unsigned char* view,
 807                       section_size_type view_size);
 808
 809     // Do a TLS Local-Dynamic to Local-Exec transition.
 810     inline void
 811     tls_ld_to_le(const Relocate_info<size, false>*, size_t relnum,
 812                  Output_segment* tls_segment,
 813                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 814                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 815                  unsigned char* view,
 816                  section_size_type view_size);
 817
 818     // Do a TLS Initial-Exec to Local-Exec transition.
 819     static inline void
 820     tls_ie_to_le(const Relocate_info<size, false>*, size_t relnum,
 821                  Output_segment* tls_segment,
 822                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 823                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 824                  unsigned char* view,
 825                  section_size_type view_size);
 826
 827     // This is set if we should skip the next reloc, which should be a
 828     // PLT32 reloc against ___tls_get_addr.
 829     bool skip_call_tls_get_addr_;
 830   };
 831
 832   // A class which returns the size required for a relocation type,
 833   // used while scanning relocs during a relocatable link.
 834   class Relocatable_size_for_reloc
 835   {
 836    public:
 837     unsigned int
 838     get_size_for_reloc(unsigned int, Relobj*);
 839   };
 840
 841   // Adjust TLS relocation type based on the options and whether this
 842   // is a local symbol.
 843   static tls::Tls_optimization
 844   optimize_tls_reloc(bool is_final, int r_type);
 845
 846   // Get the GOT section, creating it if necessary.
 847   Output_data_got<64, false>*
 848   got_section(Symbol_table*, Layout*);
 849
 850   // Get the GOT PLT section.
 851   Output_data_space*
 852   got_plt_section() const
 853   {
 854     gold_assert(this->got_plt_ != NULL);
 855     return this->got_plt_;
 856   }
 857
 858   // Get the GOT section for TLSDESC entries.
 859   Output_data_got<64, false>*
 860   got_tlsdesc_section() const
 861   {
 862     gold_assert(this->got_tlsdesc_ != NULL);
 863     return this->got_tlsdesc_;
 864   }
 865
 866   // Create the PLT section.
 867   void
 868   make_plt_section(Symbol_table* symtab, Layout* layout);
 869
 870   // Create a PLT entry for a global symbol.
 871   void
 872   make_plt_entry(Symbol_table*, Layout*, Symbol*);
 873
 874   // Create a PLT entry for a local STT_GNU_IFUNC symbol.
 875   void
 876   make_local_ifunc_plt_entry(Symbol_table*, Layout*,
 877                              Sized_relobj_file<size, false>* relobj,
 878                              unsigned int local_sym_index);
 879
 880   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
 881   void
 882   define_tls_base_symbol(Symbol_table*, Layout*);
 883
 884   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
 885   void
 886   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
 887
 888   // Create a GOT entry for the TLS module index.
 889   unsigned int
 890   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
 891                       Sized_relobj_file<size, false>* object);
 892
 893   // Get the PLT section.
 894   Output_data_plt_x86_64<size>*
 895   plt_section() const
 896   {
 897     gold_assert(this->plt_ != NULL);
 898     return this->plt_;
 899   }
 900
 901   // Get the dynamic reloc section, creating it if necessary.
 902   Reloc_section*
 903   rela_dyn_section(Layout*);
 904
 905   // Get the section to use for TLSDESC relocations.
 906   Reloc_section*
 907   rela_tlsdesc_section(Layout*) const;
 908
 909   // Get the section to use for IRELATIVE relocations.
 910   Reloc_section*
 911   rela_irelative_section(Layout*);
 912
 913   // Add a potential copy relocation.
 914   void
 915   copy_reloc(Symbol_table* symtab, Layout* layout,
 916              Sized_relobj_file<size, false>* object,
 917              unsigned int shndx, Output_section* output_section,
 918              Symbol* sym, const elfcpp::Rela<size, false>& reloc)
 919   {
 920     this->copy_relocs_.copy_reloc(symtab, layout,
 921                                   symtab->get_sized_symbol<size>(sym),
 922                                   object, shndx, output_section,
 923                                   reloc, this->rela_dyn_section(layout));
 924   }
 925
 926   // Information about this specific target which we pass to the
 927   // general Target structure.
 928   static const Target::Target_info x86_64_info;
 929
 930   // The types of GOT entries needed for this platform.
 931   // These values are exposed to the ABI in an incremental link.
 932   // Do not renumber existing values without changing the version
 933   // number of the .gnu_incremental_inputs section.
 934   enum Got_type
 935   {
 936     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
 937     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
 938     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
 939     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
 940   };
 941
 942   // This type is used as the argument to the target specific
 943   // relocation routines.  The only target specific reloc is
 944   // R_X86_64_TLSDESC against a local symbol.
 945   struct Tlsdesc_info
 946   {
 947     Tlsdesc_info(Sized_relobj_file<size, false>* a_object, unsigned int a_r_sym)
 948       : object(a_object), r_sym(a_r_sym)
 949     { }
 950
 951     // The object in which the local symbol is defined.
 952     Sized_relobj_file<size, false>* object;
 953     // The local symbol index in the object.
 954     unsigned int r_sym;
 955   };
 956
 957   // The GOT section.
 958   Output_data_got<64, false>* got_;
 959   // The PLT section.
 960   Output_data_plt_x86_64<size>* plt_;
 961   // The GOT PLT section.
 962   Output_data_space* got_plt_;
 963   // The GOT section for IRELATIVE relocations.
 964   Output_data_space* got_irelative_;
 965   // The GOT section for TLSDESC relocations.
 966   Output_data_got<64, false>* got_tlsdesc_;
 967   // The _GLOBAL_OFFSET_TABLE_ symbol.
 968   Symbol* global_offset_table_;
 969   // The dynamic reloc section.
 970   Reloc_section* rela_dyn_;
 971   // The section to use for IRELATIVE relocs.
 972   Reloc_section* rela_irelative_;
 973   // Relocs saved to avoid a COPY reloc.
 974   Copy_relocs<elfcpp::SHT_RELA, size, false> copy_relocs_;
 975   // Space for variables copied with a COPY reloc.
 976   Output_data_space* dynbss_;
 977   // Offset of the GOT entry for the TLS module index.
 978   unsigned int got_mod_index_offset_;
 979   // We handle R_X86_64_TLSDESC against a local symbol as a target
 980   // specific relocation.  Here we store the object and local symbol
 981   // index for the relocation.
 982   std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
 983   // True if the _TLS_MODULE_BASE_ symbol has been defined.
 984   bool tls_base_symbol_defined_;
 985 };
 986
 987 template<>
 988 const Target::Target_info Target_x86_64<64>::x86_64_info =
 989 {
 990   64,                   // size
 991   false,                // is_big_endian
 992   elfcpp::EM_X86_64,    // machine_code
 993   false,                // has_make_symbol
 994   false,                // has_resolve
 995   true,                 // has_code_fill
 996   true,                 // is_default_stack_executable
 997   true,                 // can_icf_inline_merge_sections
 998   '\0',                 // wrap_char
 999   "/lib/ld64.so.1",     // program interpreter
1000   0x400000,             // default_text_segment_address
1001   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1002   0x1000,               // common_pagesize (overridable by -z common-page-size)
1003   false,                // isolate_execinstr
1004   0,                    // rosegment_gap
1005   elfcpp::SHN_UNDEF,    // small_common_shndx
1006   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1007   0,                    // small_common_section_flags
1008   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1009   NULL,                 // attributes_section
1010   NULL,                 // attributes_vendor
1011   "_start"              // entry_symbol_name
1012 };
1013
1014 template<>
1015 const Target::Target_info Target_x86_64<32>::x86_64_info =
1016 {
1017   32,                   // size
1018   false,                // is_big_endian
1019   elfcpp::EM_X86_64,    // machine_code
1020   false,                // has_make_symbol
1021   false,                // has_resolve
1022   true,                 // has_code_fill
1023   true,                 // is_default_stack_executable
1024   true,                 // can_icf_inline_merge_sections
1025   '\0',                 // wrap_char
1026   "/libx32/ldx32.so.1", // program interpreter
1027   0x400000,             // default_text_segment_address
1028   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1029   0x1000,               // common_pagesize (overridable by -z common-page-size)
1030   false,                // isolate_execinstr
1031   0,                    // rosegment_gap
1032   elfcpp::SHN_UNDEF,    // small_common_shndx
1033   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1034   0,                    // small_common_section_flags
1035   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1036   NULL,                 // attributes_section
1037   NULL,                 // attributes_vendor
1038   "_start"              // entry_symbol_name
1039 };
1040
1041 // This is called when a new output section is created.  This is where
1042 // we handle the SHF_X86_64_LARGE.
1043
1044 template<int size>
1045 void
1046 Target_x86_64<size>::do_new_output_section(Output_section* os) const
1047 {
1048   if ((os->flags() & elfcpp::SHF_X86_64_LARGE) != 0)
1049     os->set_is_large_section();
1050 }
1051
1052 // Get the GOT section, creating it if necessary.
1053
1054 template<int size>
1055 Output_data_got<64, false>*
1056 Target_x86_64<size>::got_section(Symbol_table* symtab, Layout* layout)
1057 {
1058   if (this->got_ == NULL)
1059     {
1060       gold_assert(symtab != NULL && layout != NULL);
1061
1062       // When using -z now, we can treat .got.plt as a relro section.
1063       // Without -z now, it is modified after program startup by lazy
1064       // PLT relocations.
1065       bool is_got_plt_relro = parameters->options().now();
1066       Output_section_order got_order = (is_got_plt_relro
1067                                         ? ORDER_RELRO
1068                                         : ORDER_RELRO_LAST);
1069       Output_section_order got_plt_order = (is_got_plt_relro
1070                                             ? ORDER_RELRO
1071                                             : ORDER_NON_RELRO_FIRST);
1072
1073       this->got_ = new Output_data_got<64, false>();
1074
1075       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1076                                       (elfcpp::SHF_ALLOC
1077                                        | elfcpp::SHF_WRITE),
1078                                       this->got_, got_order, true);
1079
1080       this->got_plt_ = new Output_data_space(8, "** GOT PLT");
1081       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1082                                       (elfcpp::SHF_ALLOC
1083                                        | elfcpp::SHF_WRITE),
1084                                       this->got_plt_, got_plt_order,
1085                                       is_got_plt_relro);
1086
1087       // The first three entries are reserved.
1088       this->got_plt_->set_current_data_size(3 * 8);
1089
1090       if (!is_got_plt_relro)
1091         {
1092           // Those bytes can go into the relro segment.
1093           layout->increase_relro(3 * 8);
1094         }
1095
1096       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1097       this->global_offset_table_ =
1098         symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1099                                       Symbol_table::PREDEFINED,
1100                                       this->got_plt_,
1101                                       0, 0, elfcpp::STT_OBJECT,
1102                                       elfcpp::STB_LOCAL,
1103                                       elfcpp::STV_HIDDEN, 0,
1104                                       false, false);
1105
1106       // If there are any IRELATIVE relocations, they get GOT entries
1107       // in .got.plt after the jump slot entries.
1108       this->got_irelative_ = new Output_data_space(8, "** GOT IRELATIVE PLT");
1109       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1110                                       (elfcpp::SHF_ALLOC
1111                                        | elfcpp::SHF_WRITE),
1112                                       this->got_irelative_,
1113                                       got_plt_order, is_got_plt_relro);
1114
1115       // If there are any TLSDESC relocations, they get GOT entries in
1116       // .got.plt after the jump slot and IRELATIVE entries.
1117       this->got_tlsdesc_ = new Output_data_got<64, false>();
1118       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1119                                       (elfcpp::SHF_ALLOC
1120                                        | elfcpp::SHF_WRITE),
1121                                       this->got_tlsdesc_,
1122                                       got_plt_order, is_got_plt_relro);
1123     }
1124
1125   return this->got_;
1126 }
1127
1128 // Get the dynamic reloc section, creating it if necessary.
1129
1130 template<int size>
1131 typename Target_x86_64<size>::Reloc_section*
1132 Target_x86_64<size>::rela_dyn_section(Layout* layout)
1133 {
1134   if (this->rela_dyn_ == NULL)
1135     {
1136       gold_assert(layout != NULL);
1137       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
1138       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1139                                       elfcpp::SHF_ALLOC, this->rela_dyn_,
1140                                       ORDER_DYNAMIC_RELOCS, false);
1141     }
1142   return this->rela_dyn_;
1143 }
1144
1145 // Get the section to use for IRELATIVE relocs, creating it if
1146 // necessary.  These go in .rela.dyn, but only after all other dynamic
1147 // relocations.  They need to follow the other dynamic relocations so
1148 // that they can refer to global variables initialized by those
1149 // relocs.
1150
1151 template<int size>
1152 typename Target_x86_64<size>::Reloc_section*
1153 Target_x86_64<size>::rela_irelative_section(Layout* layout)
1154 {
1155   if (this->rela_irelative_ == NULL)
1156     {
1157       // Make sure we have already created the dynamic reloc section.
1158       this->rela_dyn_section(layout);
1159       this->rela_irelative_ = new Reloc_section(false);
1160       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1161                                       elfcpp::SHF_ALLOC, this->rela_irelative_,
1162                                       ORDER_DYNAMIC_RELOCS, false);
1163       gold_assert(this->rela_dyn_->output_section()
1164                   == this->rela_irelative_->output_section());
1165     }
1166   return this->rela_irelative_;
1167 }
1168
1169 // Initialize the PLT section.
1170
1171 template<int size>
1172 void
1173 Output_data_plt_x86_64<size>::init(Layout* layout)
1174 {
1175   this->rel_ = new Reloc_section(false);
1176   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1177                                   elfcpp::SHF_ALLOC, this->rel_,
1178                                   ORDER_DYNAMIC_PLT_RELOCS, false);
1179 }
1180
1181 template<int size>
1182 void
1183 Output_data_plt_x86_64<size>::do_adjust_output_section(Output_section* os)
1184 {
1185   os->set_entsize(this->get_plt_entry_size());
1186 }
1187
1188 // Add an entry to the PLT.
1189
1190 template<int size>
1191 void
1192 Output_data_plt_x86_64<size>::add_entry(Symbol_table* symtab, Layout* layout,
1193                                         Symbol* gsym)
1194 {
1195   gold_assert(!gsym->has_plt_offset());
1196
1197   unsigned int plt_index;
1198   off_t plt_offset;
1199   section_offset_type got_offset;
1200
1201   unsigned int* pcount;
1202   unsigned int offset;
1203   unsigned int reserved;
1204   Output_data_space* got;
1205   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1206       && gsym->can_use_relative_reloc(false))
1207     {
1208       pcount = &this->irelative_count_;
1209       offset = 0;
1210       reserved = 0;
1211       got = this->got_irelative_;
1212     }
1213   else
1214     {
1215       pcount = &this->count_;
1216       offset = 1;
1217       reserved = 3;
1218       got = this->got_plt_;
1219     }
1220
1221   if (!this->is_data_size_valid())
1222     {
1223       // Note that when setting the PLT offset for a non-IRELATIVE
1224       // entry we skip the initial reserved PLT entry.
1225       plt_index = *pcount + offset;
1226       plt_offset = plt_index * this->get_plt_entry_size();
1227
1228       ++*pcount;
1229
1230       got_offset = (plt_index - offset + reserved) * 8;
1231       gold_assert(got_offset == got->current_data_size());
1232
1233       // Every PLT entry needs a GOT entry which points back to the PLT
1234       // entry (this will be changed by the dynamic linker, normally
1235       // lazily when the function is called).
1236       got->set_current_data_size(got_offset + 8);
1237     }
1238   else
1239     {
1240       // FIXME: This is probably not correct for IRELATIVE relocs.
1241
1242       // For incremental updates, find an available slot.
1243       plt_offset = this->free_list_.allocate(this->get_plt_entry_size(),
1244                                              this->get_plt_entry_size(), 0);
1245       if (plt_offset == -1)
1246         gold_fallback(_("out of patch space (PLT);"
1247                         " relink with --incremental-full"));
1248
1249       // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1250       // can be calculated from the PLT index, adjusting for the three
1251       // reserved entries at the beginning of the GOT.
1252       plt_index = plt_offset / this->get_plt_entry_size() - 1;
1253       got_offset = (plt_index - offset + reserved) * 8;
1254     }
1255
1256   gsym->set_plt_offset(plt_offset);
1257
1258   // Every PLT entry needs a reloc.
1259   this->add_relocation(symtab, layout, gsym, got_offset);
1260
1261   // Note that we don't need to save the symbol.  The contents of the
1262   // PLT are independent of which symbols are used.  The symbols only
1263   // appear in the relocations.
1264 }
1265
1266 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.  Return
1267 // the PLT offset.
1268
1269 template<int size>
1270 unsigned int
1271 Output_data_plt_x86_64<size>::add_local_ifunc_entry(
1272     Symbol_table* symtab,
1273     Layout* layout,
1274     Sized_relobj_file<size, false>* relobj,
1275     unsigned int local_sym_index)
1276 {
1277   unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1278   ++this->irelative_count_;
1279
1280   section_offset_type got_offset = this->got_irelative_->current_data_size();
1281
1282   // Every PLT entry needs a GOT entry which points back to the PLT
1283   // entry.
1284   this->got_irelative_->set_current_data_size(got_offset + 8);
1285
1286   // Every PLT entry needs a reloc.
1287   Reloc_section* rela = this->rela_irelative(symtab, layout);
1288   rela->add_symbolless_local_addend(relobj, local_sym_index,
1289                                     elfcpp::R_X86_64_IRELATIVE,
1290                                     this->got_irelative_, got_offset, 0);
1291
1292   return plt_offset;
1293 }
1294
1295 // Add the relocation for a PLT entry.
1296
1297 template<int size>
1298 void
1299 Output_data_plt_x86_64<size>::add_relocation(Symbol_table* symtab,
1300                                              Layout* layout,
1301                                              Symbol* gsym,
1302                                              unsigned int got_offset)
1303 {
1304   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1305       && gsym->can_use_relative_reloc(false))
1306     {
1307       Reloc_section* rela = this->rela_irelative(symtab, layout);
1308       rela->add_symbolless_global_addend(gsym, elfcpp::R_X86_64_IRELATIVE,
1309                                          this->got_irelative_, got_offset, 0);
1310     }
1311   else
1312     {
1313       gsym->set_needs_dynsym_entry();
1314       this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
1315                              got_offset, 0);
1316     }
1317 }
1318
1319 // Return where the TLSDESC relocations should go, creating it if
1320 // necessary.  These follow the JUMP_SLOT relocations.
1321
1322 template<int size>
1323 typename Output_data_plt_x86_64<size>::Reloc_section*
1324 Output_data_plt_x86_64<size>::rela_tlsdesc(Layout* layout)
1325 {
1326   if (this->tlsdesc_rel_ == NULL)
1327     {
1328       this->tlsdesc_rel_ = new Reloc_section(false);
1329       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1330                                       elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
1331                                       ORDER_DYNAMIC_PLT_RELOCS, false);
1332       gold_assert(this->tlsdesc_rel_->output_section()
1333                   == this->rel_->output_section());
1334     }
1335   return this->tlsdesc_rel_;
1336 }
1337
1338 // Return where the IRELATIVE relocations should go in the PLT.  These
1339 // follow the JUMP_SLOT and the TLSDESC relocations.
1340
1341 template<int size>
1342 typename Output_data_plt_x86_64<size>::Reloc_section*
1343 Output_data_plt_x86_64<size>::rela_irelative(Symbol_table* symtab,
1344                                              Layout* layout)
1345 {
1346   if (this->irelative_rel_ == NULL)
1347     {
1348       // Make sure we have a place for the TLSDESC relocations, in
1349       // case we see any later on.
1350       this->rela_tlsdesc(layout);
1351       this->irelative_rel_ = new Reloc_section(false);
1352       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1353                                       elfcpp::SHF_ALLOC, this->irelative_rel_,
1354                                       ORDER_DYNAMIC_PLT_RELOCS, false);
1355       gold_assert(this->irelative_rel_->output_section()
1356                   == this->rel_->output_section());
1357
1358       if (parameters->doing_static_link())
1359         {
1360           // A statically linked executable will only have a .rela.plt
1361           // section to hold R_X86_64_IRELATIVE relocs for
1362           // STT_GNU_IFUNC symbols.  The library will use these
1363           // symbols to locate the IRELATIVE relocs at program startup
1364           // time.
1365           symtab->define_in_output_data("__rela_iplt_start", NULL,
1366                                         Symbol_table::PREDEFINED,
1367                                         this->irelative_rel_, 0, 0,
1368                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1369                                         elfcpp::STV_HIDDEN, 0, false, true);
1370           symtab->define_in_output_data("__rela_iplt_end", NULL,
1371                                         Symbol_table::PREDEFINED,
1372                                         this->irelative_rel_, 0, 0,
1373                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1374                                         elfcpp::STV_HIDDEN, 0, true, true);
1375         }
1376     }
1377   return this->irelative_rel_;
1378 }
1379
1380 // Return the PLT address to use for a global symbol.
1381
1382 template<int size>
1383 uint64_t
1384 Output_data_plt_x86_64<size>::address_for_global(const Symbol* gsym)
1385 {
1386   uint64_t offset = 0;
1387   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1388       && gsym->can_use_relative_reloc(false))
1389     offset = (this->count_ + 1) * this->get_plt_entry_size();
1390   return this->address() + offset + gsym->plt_offset();
1391 }
1392
1393 // Return the PLT address to use for a local symbol.  These are always
1394 // IRELATIVE relocs.
1395
1396 template<int size>
1397 uint64_t
1398 Output_data_plt_x86_64<size>::address_for_local(const Relobj* object,
1399                                                 unsigned int r_sym)
1400 {
1401   return (this->address()
1402           + (this->count_ + 1) * this->get_plt_entry_size()
1403           + object->local_plt_offset(r_sym));
1404 }
1405
1406 // Set the final size.
1407 template<int size>
1408 void
1409 Output_data_plt_x86_64<size>::set_final_data_size()
1410 {
1411   unsigned int count = this->count_ + this->irelative_count_;
1412   if (this->has_tlsdesc_entry())
1413     ++count;
1414   this->set_data_size((count + 1) * this->get_plt_entry_size());
1415 }
1416
1417 // The first entry in the PLT for an executable.
1418
1419 template<int size>
1420 const unsigned char
1421 Output_data_plt_x86_64_standard<size>::first_plt_entry[plt_entry_size] =
1422 {
1423   // From AMD64 ABI Draft 0.98, page 76
1424   0xff, 0x35,   // pushq contents of memory address
1425   0, 0, 0, 0,   // replaced with address of .got + 8
1426   0xff, 0x25,   // jmp indirect
1427   0, 0, 0, 0,   // replaced with address of .got + 16
1428   0x90, 0x90, 0x90, 0x90   // noop (x4)
1429 };
1430
1431 template<int size>
1432 void
1433 Output_data_plt_x86_64_standard<size>::do_fill_first_plt_entry(
1434     unsigned char* pov,
1435     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1436     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
1437 {
1438   memcpy(pov, first_plt_entry, plt_entry_size);
1439   // We do a jmp relative to the PC at the end of this instruction.
1440   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1441                                               (got_address + 8
1442                                                - (plt_address + 6)));
1443   elfcpp::Swap<32, false>::writeval(pov + 8,
1444                                     (got_address + 16
1445                                      - (plt_address + 12)));
1446 }
1447
1448 // Subsequent entries in the PLT for an executable.
1449
1450 template<int size>
1451 const unsigned char
1452 Output_data_plt_x86_64_standard<size>::plt_entry[plt_entry_size] =
1453 {
1454   // From AMD64 ABI Draft 0.98, page 76
1455   0xff, 0x25,   // jmpq indirect
1456   0, 0, 0, 0,   // replaced with address of symbol in .got
1457   0x68,         // pushq immediate
1458   0, 0, 0, 0,   // replaced with offset into relocation table
1459   0xe9,         // jmpq relative
1460   0, 0, 0, 0    // replaced with offset to start of .plt
1461 };
1462
1463 template<int size>
1464 unsigned int
1465 Output_data_plt_x86_64_standard<size>::do_fill_plt_entry(
1466     unsigned char* pov,
1467     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1468     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1469     unsigned int got_offset,
1470     unsigned int plt_offset,
1471     unsigned int plt_index)
1472 {
1473   memcpy(pov, plt_entry, plt_entry_size);
1474   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1475                                               (got_address + got_offset
1476                                                - (plt_address + plt_offset
1477                                                   + 6)));
1478
1479   elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
1480   elfcpp::Swap<32, false>::writeval(pov + 12,
1481                                     - (plt_offset + plt_entry_size));
1482
1483   return 6;
1484 }
1485
1486 // The reserved TLSDESC entry in the PLT for an executable.
1487
1488 template<int size>
1489 const unsigned char
1490 Output_data_plt_x86_64_standard<size>::tlsdesc_plt_entry[plt_entry_size] =
1491 {
1492   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1493   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1494   0xff, 0x35,   // pushq x(%rip)
1495   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1496   0xff, 0x25,   // jmpq *y(%rip)
1497   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
1498   0x0f, 0x1f,   // nop
1499   0x40, 0
1500 };
1501
1502 template<int size>
1503 void
1504 Output_data_plt_x86_64_standard<size>::do_fill_tlsdesc_entry(
1505     unsigned char* pov,
1506     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1507     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1508     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
1509     unsigned int tlsdesc_got_offset,
1510     unsigned int plt_offset)
1511 {
1512   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
1513   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1514                                               (got_address + 8
1515                                                - (plt_address + plt_offset
1516                                                   + 6)));
1517   elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
1518                                               (got_base
1519                                                + tlsdesc_got_offset
1520                                                - (plt_address + plt_offset
1521                                                   + 12)));
1522 }
1523
1524 // The .eh_frame unwind information for the PLT.
1525
1526 template<int size>
1527 const unsigned char
1528 Output_data_plt_x86_64<size>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1529 {
1530   1,                            // CIE version.
1531   'z',                          // Augmentation: augmentation size included.
1532   'R',                          // Augmentation: FDE encoding included.
1533   '\0',                         // End of augmentation string.
1534   1,                            // Code alignment factor.
1535   0x78,                         // Data alignment factor.
1536   16,                           // Return address column.
1537   1,                            // Augmentation size.
1538   (elfcpp::DW_EH_PE_pcrel       // FDE encoding.
1539    | elfcpp::DW_EH_PE_sdata4),
1540   elfcpp::DW_CFA_def_cfa, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1541   elfcpp::DW_CFA_offset + 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1542   elfcpp::DW_CFA_nop,           // Align to 16 bytes.
1543   elfcpp::DW_CFA_nop
1544 };
1545
1546 template<int size>
1547 const unsigned char
1548 Output_data_plt_x86_64_standard<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1549 {
1550   0, 0, 0, 0,                           // Replaced with offset to .plt.
1551   0, 0, 0, 0,                           // Replaced with size of .plt.
1552   0,                                    // Augmentation size.
1553   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
1554   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
1555   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
1556   elfcpp::DW_CFA_advance_loc + 10,      // Advance 10 to __PLT__ + 16.
1557   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
1558   11,                                   // Block length.
1559   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
1560   elfcpp::DW_OP_breg16, 0,              // Push %rip.
1561   elfcpp::DW_OP_lit15,                  // Push 0xf.
1562   elfcpp::DW_OP_and,                    // & (%rip & 0xf).
1563   elfcpp::DW_OP_lit11,                  // Push 0xb.
1564   elfcpp::DW_OP_ge,                     // >= ((%rip & 0xf) >= 0xb)
1565   elfcpp::DW_OP_lit3,                   // Push 3.
1566   elfcpp::DW_OP_shl,                    // << (((%rip & 0xf) >= 0xb) << 3)
1567   elfcpp::DW_OP_plus,                   // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1568   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
1569   elfcpp::DW_CFA_nop,
1570   elfcpp::DW_CFA_nop,
1571   elfcpp::DW_CFA_nop
1572 };
1573
1574 // Write out the PLT.  This uses the hand-coded instructions above,
1575 // and adjusts them as needed.  This is specified by the AMD64 ABI.
1576
1577 template<int size>
1578 void
1579 Output_data_plt_x86_64<size>::do_write(Output_file* of)
1580 {
1581   const off_t offset = this->offset();
1582   const section_size_type oview_size =
1583     convert_to_section_size_type(this->data_size());
1584   unsigned char* const oview = of->get_output_view(offset, oview_size);
1585
1586   const off_t got_file_offset = this->got_plt_->offset();
1587   gold_assert(parameters->incremental_update()
1588               || (got_file_offset + this->got_plt_->data_size()
1589                   == this->got_irelative_->offset()));
1590   const section_size_type got_size =
1591     convert_to_section_size_type(this->got_plt_->data_size()
1592                                  + this->got_irelative_->data_size());
1593   unsigned char* const got_view = of->get_output_view(got_file_offset,
1594                                                       got_size);
1595
1596   unsigned char* pov = oview;
1597
1598   // The base address of the .plt section.
1599   typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
1600   // The base address of the .got section.
1601   typename elfcpp::Elf_types<size>::Elf_Addr got_base = this->got_->address();
1602   // The base address of the PLT portion of the .got section,
1603   // which is where the GOT pointer will point, and where the
1604   // three reserved GOT entries are located.
1605   typename elfcpp::Elf_types<size>::Elf_Addr got_address
1606     = this->got_plt_->address();
1607
1608   this->fill_first_plt_entry(pov, got_address, plt_address);
1609   pov += this->get_plt_entry_size();
1610
1611   unsigned char* got_pov = got_view;
1612
1613   // The first entry in the GOT is the address of the .dynamic section
1614   // aka the PT_DYNAMIC segment.  The next two entries are reserved.
1615   // We saved space for them when we created the section in
1616   // Target_x86_64::got_section.
1617   Output_section* dynamic = this->layout_->dynamic_section();
1618   uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1619   elfcpp::Swap<64, false>::writeval(got_pov, dynamic_addr);
1620   got_pov += 8;
1621   memset(got_pov, 0, 16);
1622   got_pov += 16;
1623
1624   unsigned int plt_offset = this->get_plt_entry_size();
1625   unsigned int got_offset = 24;
1626   const unsigned int count = this->count_ + this->irelative_count_;
1627   for (unsigned int plt_index = 0;
1628        plt_index < count;
1629        ++plt_index,
1630          pov += this->get_plt_entry_size(),
1631          got_pov += 8,
1632          plt_offset += this->get_plt_entry_size(),
1633          got_offset += 8)
1634     {
1635       // Set and adjust the PLT entry itself.
1636       unsigned int lazy_offset = this->fill_plt_entry(pov,
1637                                                       got_address, plt_address,
1638                                                       got_offset, plt_offset,
1639                                                       plt_index);
1640
1641       // Set the entry in the GOT.
1642       elfcpp::Swap<64, false>::writeval(got_pov,
1643                                         plt_address + plt_offset + lazy_offset);
1644     }
1645
1646   if (this->has_tlsdesc_entry())
1647     {
1648       // Set and adjust the reserved TLSDESC PLT entry.
1649       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
1650       this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
1651                                tlsdesc_got_offset, plt_offset);
1652       pov += this->get_plt_entry_size();
1653     }
1654
1655   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1656   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1657
1658   of->write_output_view(offset, oview_size, oview);
1659   of->write_output_view(got_file_offset, got_size, got_view);
1660 }
1661
1662 // Create the PLT section.
1663
1664 template<int size>
1665 void
1666 Target_x86_64<size>::make_plt_section(Symbol_table* symtab, Layout* layout)
1667 {
1668   if (this->plt_ == NULL)
1669     {
1670       // Create the GOT sections first.
1671       this->got_section(symtab, layout);
1672
1673       this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
1674                                        this->got_irelative_);
1675
1676       // Add unwind information if requested.
1677       if (parameters->options().ld_generated_unwind_info())
1678         this->plt_->add_eh_frame(layout);
1679
1680       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1681                                       (elfcpp::SHF_ALLOC
1682                                        | elfcpp::SHF_EXECINSTR),
1683                                       this->plt_, ORDER_PLT, false);
1684
1685       // Make the sh_info field of .rela.plt point to .plt.
1686       Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1687       rela_plt_os->set_info_section(this->plt_->output_section());
1688     }
1689 }
1690
1691 // Return the section for TLSDESC relocations.
1692
1693 template<int size>
1694 typename Target_x86_64<size>::Reloc_section*
1695 Target_x86_64<size>::rela_tlsdesc_section(Layout* layout) const
1696 {
1697   return this->plt_section()->rela_tlsdesc(layout);
1698 }
1699
1700 // Create a PLT entry for a global symbol.
1701
1702 template<int size>
1703 void
1704 Target_x86_64<size>::make_plt_entry(Symbol_table* symtab, Layout* layout,
1705                                     Symbol* gsym)
1706 {
1707   if (gsym->has_plt_offset())
1708     return;
1709
1710   if (this->plt_ == NULL)
1711     this->make_plt_section(symtab, layout);
1712
1713   this->plt_->add_entry(symtab, layout, gsym);
1714 }
1715
1716 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1717
1718 template<int size>
1719 void
1720 Target_x86_64<size>::make_local_ifunc_plt_entry(
1721     Symbol_table* symtab, Layout* layout,
1722     Sized_relobj_file<size, false>* relobj,
1723     unsigned int local_sym_index)
1724 {
1725   if (relobj->local_has_plt_offset(local_sym_index))
1726     return;
1727   if (this->plt_ == NULL)
1728     this->make_plt_section(symtab, layout);
1729   unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1730                                                               relobj,
1731                                                               local_sym_index);
1732   relobj->set_local_plt_offset(local_sym_index, plt_offset);
1733 }
1734
1735 // Return the number of entries in the PLT.
1736
1737 template<int size>
1738 unsigned int
1739 Target_x86_64<size>::plt_entry_count() const
1740 {
1741   if (this->plt_ == NULL)
1742     return 0;
1743   return this->plt_->entry_count();
1744 }
1745
1746 // Return the offset of the first non-reserved PLT entry.
1747
1748 template<int size>
1749 unsigned int
1750 Target_x86_64<size>::first_plt_entry_offset() const
1751 {
1752   return this->plt_->first_plt_entry_offset();
1753 }
1754
1755 // Return the size of each PLT entry.
1756
1757 template<int size>
1758 unsigned int
1759 Target_x86_64<size>::plt_entry_size() const
1760 {
1761   return this->plt_->get_plt_entry_size();
1762 }
1763
1764 // Create the GOT and PLT sections for an incremental update.
1765
1766 template<int size>
1767 Output_data_got_base*
1768 Target_x86_64<size>::init_got_plt_for_update(Symbol_table* symtab,
1769                                        Layout* layout,
1770                                        unsigned int got_count,
1771                                        unsigned int plt_count)
1772 {
1773   gold_assert(this->got_ == NULL);
1774
1775   this->got_ = new Output_data_got<64, false>(got_count * 8);
1776   layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1777                                   (elfcpp::SHF_ALLOC
1778                                    | elfcpp::SHF_WRITE),
1779                                   this->got_, ORDER_RELRO_LAST,
1780                                   true);
1781
1782   // Add the three reserved entries.
1783   this->got_plt_ = new Output_data_space((plt_count + 3) * 8, 8, "** GOT PLT");
1784   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1785                                   (elfcpp::SHF_ALLOC
1786                                    | elfcpp::SHF_WRITE),
1787                                   this->got_plt_, ORDER_NON_RELRO_FIRST,
1788                                   false);
1789
1790   // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1791   this->global_offset_table_ =
1792     symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1793                                   Symbol_table::PREDEFINED,
1794                                   this->got_plt_,
1795                                   0, 0, elfcpp::STT_OBJECT,
1796                                   elfcpp::STB_LOCAL,
1797                                   elfcpp::STV_HIDDEN, 0,
1798                                   false, false);
1799
1800   // If there are any TLSDESC relocations, they get GOT entries in
1801   // .got.plt after the jump slot entries.
1802   // FIXME: Get the count for TLSDESC entries.
1803   this->got_tlsdesc_ = new Output_data_got<64, false>(0);
1804   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1805                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1806                                   this->got_tlsdesc_,
1807                                   ORDER_NON_RELRO_FIRST, false);
1808
1809   // If there are any IRELATIVE relocations, they get GOT entries in
1810   // .got.plt after the jump slot and TLSDESC entries.
1811   this->got_irelative_ = new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1812   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1813                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1814                                   this->got_irelative_,
1815                                   ORDER_NON_RELRO_FIRST, false);
1816
1817   // Create the PLT section.
1818   this->plt_ = this->make_data_plt(layout, this->got_,
1819                                    this->got_plt_,
1820                                    this->got_irelative_,
1821                                    plt_count);
1822
1823   // Add unwind information if requested.
1824   if (parameters->options().ld_generated_unwind_info())
1825     this->plt_->add_eh_frame(layout);
1826
1827   layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1828                                   elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
1829                                   this->plt_, ORDER_PLT, false);
1830
1831   // Make the sh_info field of .rela.plt point to .plt.
1832   Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1833   rela_plt_os->set_info_section(this->plt_->output_section());
1834
1835   // Create the rela_dyn section.
1836   this->rela_dyn_section(layout);
1837
1838   return this->got_;
1839 }
1840
1841 // Reserve a GOT entry for a local symbol, and regenerate any
1842 // necessary dynamic relocations.
1843
1844 template<int size>
1845 void
1846 Target_x86_64<size>::reserve_local_got_entry(
1847     unsigned int got_index,
1848     Sized_relobj<size, false>* obj,
1849     unsigned int r_sym,
1850     unsigned int got_type)
1851 {
1852   unsigned int got_offset = got_index * 8;
1853   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1854
1855   this->got_->reserve_local(got_index, obj, r_sym, got_type);
1856   switch (got_type)
1857     {
1858     case GOT_TYPE_STANDARD:
1859       if (parameters->options().output_is_position_independent())
1860         rela_dyn->add_local_relative(obj, r_sym, elfcpp::R_X86_64_RELATIVE,
1861                                      this->got_, got_offset, 0, false);
1862       break;
1863     case GOT_TYPE_TLS_OFFSET:
1864       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_TPOFF64,
1865                           this->got_, got_offset, 0);
1866       break;
1867     case GOT_TYPE_TLS_PAIR:
1868       this->got_->reserve_slot(got_index + 1);
1869       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_DTPMOD64,
1870                           this->got_, got_offset, 0);
1871       break;
1872     case GOT_TYPE_TLS_DESC:
1873       gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
1874       // this->got_->reserve_slot(got_index + 1);
1875       // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
1876       //                               this->got_, got_offset, 0);
1877       break;
1878     default:
1879       gold_unreachable();
1880     }
1881 }
1882
1883 // Reserve a GOT entry for a global symbol, and regenerate any
1884 // necessary dynamic relocations.
1885
1886 template<int size>
1887 void
1888 Target_x86_64<size>::reserve_global_got_entry(unsigned int got_index,
1889                                               Symbol* gsym,
1890                                               unsigned int got_type)
1891 {
1892   unsigned int got_offset = got_index * 8;
1893   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1894
1895   this->got_->reserve_global(got_index, gsym, got_type);
1896   switch (got_type)
1897     {
1898     case GOT_TYPE_STANDARD:
1899       if (!gsym->final_value_is_known())
1900         {
1901           if (gsym->is_from_dynobj()
1902               || gsym->is_undefined()
1903               || gsym->is_preemptible()
1904               || gsym->type() == elfcpp::STT_GNU_IFUNC)
1905             rela_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT,
1906                                  this->got_, got_offset, 0);
1907           else
1908             rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
1909                                           this->got_, got_offset, 0, false);
1910         }
1911       break;
1912     case GOT_TYPE_TLS_OFFSET:
1913       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TPOFF64,
1914                                     this->got_, got_offset, 0, false);
1915       break;
1916     case GOT_TYPE_TLS_PAIR:
1917       this->got_->reserve_slot(got_index + 1);
1918       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPMOD64,
1919                                     this->got_, got_offset, 0, false);
1920       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPOFF64,
1921                                     this->got_, got_offset + 8, 0, false);
1922       break;
1923     case GOT_TYPE_TLS_DESC:
1924       this->got_->reserve_slot(got_index + 1);
1925       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TLSDESC,
1926                                     this->got_, got_offset, 0, false);
1927       break;
1928     default:
1929       gold_unreachable();
1930     }
1931 }
1932
1933 // Register an existing PLT entry for a global symbol.
1934
1935 template<int size>
1936 void
1937 Target_x86_64<size>::register_global_plt_entry(Symbol_table* symtab,
1938                                                Layout* layout,
1939                                                unsigned int plt_index,
1940                                                Symbol* gsym)
1941 {
1942   gold_assert(this->plt_ != NULL);
1943   gold_assert(!gsym->has_plt_offset());
1944
1945   this->plt_->reserve_slot(plt_index);
1946
1947   gsym->set_plt_offset((plt_index + 1) * this->plt_entry_size());
1948
1949   unsigned int got_offset = (plt_index + 3) * 8;
1950   this->plt_->add_relocation(symtab, layout, gsym, got_offset);
1951 }
1952
1953 // Force a COPY relocation for a given symbol.
1954
1955 template<int size>
1956 void
1957 Target_x86_64<size>::emit_copy_reloc(
1958     Symbol_table* symtab, Symbol* sym, Output_section* os, off_t offset)
1959 {
1960   this->copy_relocs_.emit_copy_reloc(symtab,
1961                                      symtab->get_sized_symbol<size>(sym),
1962                                      os,
1963                                      offset,
1964                                      this->rela_dyn_section(NULL));
1965 }
1966
1967 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1968
1969 template<int size>
1970 void
1971 Target_x86_64<size>::define_tls_base_symbol(Symbol_table* symtab,
1972                                             Layout* layout)
1973 {
1974   if (this->tls_base_symbol_defined_)
1975     return;
1976
1977   Output_segment* tls_segment = layout->tls_segment();
1978   if (tls_segment != NULL)
1979     {
1980       bool is_exec = parameters->options().output_is_executable();
1981       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1982                                        Symbol_table::PREDEFINED,
1983                                        tls_segment, 0, 0,
1984                                        elfcpp::STT_TLS,
1985                                        elfcpp::STB_LOCAL,
1986                                        elfcpp::STV_HIDDEN, 0,
1987                                        (is_exec
1988                                         ? Symbol::SEGMENT_END
1989                                         : Symbol::SEGMENT_START),
1990                                        true);
1991     }
1992   this->tls_base_symbol_defined_ = true;
1993 }
1994
1995 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1996
1997 template<int size>
1998 void
1999 Target_x86_64<size>::reserve_tlsdesc_entries(Symbol_table* symtab,
2000                                              Layout* layout)
2001 {
2002   if (this->plt_ == NULL)
2003     this->make_plt_section(symtab, layout);
2004
2005   if (!this->plt_->has_tlsdesc_entry())
2006     {
2007       // Allocate the TLSDESC_GOT entry.
2008       Output_data_got<64, false>* got = this->got_section(symtab, layout);
2009       unsigned int got_offset = got->add_constant(0);
2010
2011       // Allocate the TLSDESC_PLT entry.
2012       this->plt_->reserve_tlsdesc_entry(got_offset);
2013     }
2014 }
2015
2016 // Create a GOT entry for the TLS module index.
2017
2018 template<int size>
2019 unsigned int
2020 Target_x86_64<size>::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2021                                          Sized_relobj_file<size, false>* object)
2022 {
2023   if (this->got_mod_index_offset_ == -1U)
2024     {
2025       gold_assert(symtab != NULL && layout != NULL && object != NULL);
2026       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
2027       Output_data_got<64, false>* got = this->got_section(symtab, layout);
2028       unsigned int got_offset = got->add_constant(0);
2029       rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
2030                           got_offset, 0);
2031       got->add_constant(0);
2032       this->got_mod_index_offset_ = got_offset;
2033     }
2034   return this->got_mod_index_offset_;
2035 }
2036
2037 // Optimize the TLS relocation type based on what we know about the
2038 // symbol.  IS_FINAL is true if the final address of this symbol is
2039 // known at link time.
2040
2041 template<int size>
2042 tls::Tls_optimization
2043 Target_x86_64<size>::optimize_tls_reloc(bool is_final, int r_type)
2044 {
2045   // If we are generating a shared library, then we can't do anything
2046   // in the linker.
2047   if (parameters->options().shared())
2048     return tls::TLSOPT_NONE;
2049
2050   switch (r_type)
2051     {
2052     case elfcpp::R_X86_64_TLSGD:
2053     case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2054     case elfcpp::R_X86_64_TLSDESC_CALL:
2055       // These are General-Dynamic which permits fully general TLS
2056       // access.  Since we know that we are generating an executable,
2057       // we can convert this to Initial-Exec.  If we also know that
2058       // this is a local symbol, we can further switch to Local-Exec.
2059       if (is_final)
2060         return tls::TLSOPT_TO_LE;
2061       return tls::TLSOPT_TO_IE;
2062
2063     case elfcpp::R_X86_64_TLSLD:
2064       // This is Local-Dynamic, which refers to a local symbol in the
2065       // dynamic TLS block.  Since we know that we generating an
2066       // executable, we can switch to Local-Exec.
2067       return tls::TLSOPT_TO_LE;
2068
2069     case elfcpp::R_X86_64_DTPOFF32:
2070     case elfcpp::R_X86_64_DTPOFF64:
2071       // Another Local-Dynamic reloc.
2072       return tls::TLSOPT_TO_LE;
2073
2074     case elfcpp::R_X86_64_GOTTPOFF:
2075       // These are Initial-Exec relocs which get the thread offset
2076       // from the GOT.  If we know that we are linking against the
2077       // local symbol, we can switch to Local-Exec, which links the
2078       // thread offset into the instruction.
2079       if (is_final)
2080         return tls::TLSOPT_TO_LE;
2081       return tls::TLSOPT_NONE;
2082
2083     case elfcpp::R_X86_64_TPOFF32:
2084       // When we already have Local-Exec, there is nothing further we
2085       // can do.
2086       return tls::TLSOPT_NONE;
2087
2088     default:
2089       gold_unreachable();
2090     }
2091 }
2092
2093 // Get the Reference_flags for a particular relocation.
2094
2095 template<int size>
2096 int
2097 Target_x86_64<size>::Scan::get_reference_flags(unsigned int r_type)
2098 {
2099   switch (r_type)
2100     {
2101     case elfcpp::R_X86_64_NONE:
2102     case elfcpp::R_X86_64_GNU_VTINHERIT:
2103     case elfcpp::R_X86_64_GNU_VTENTRY:
2104     case elfcpp::R_X86_64_GOTPC32:
2105     case elfcpp::R_X86_64_GOTPC64:
2106       // No symbol reference.
2107       return 0;
2108
2109     case elfcpp::R_X86_64_64:
2110     case elfcpp::R_X86_64_32:
2111     case elfcpp::R_X86_64_32S:
2112     case elfcpp::R_X86_64_16:
2113     case elfcpp::R_X86_64_8:
2114       return Symbol::ABSOLUTE_REF;
2115
2116     case elfcpp::R_X86_64_PC64:
2117     case elfcpp::R_X86_64_PC32:
2118     case elfcpp::R_X86_64_PC16:
2119     case elfcpp::R_X86_64_PC8:
2120     case elfcpp::R_X86_64_GOTOFF64:
2121       return Symbol::RELATIVE_REF;
2122
2123     case elfcpp::R_X86_64_PLT32:
2124     case elfcpp::R_X86_64_PLTOFF64:
2125       return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
2126
2127     case elfcpp::R_X86_64_GOT64:
2128     case elfcpp::R_X86_64_GOT32:
2129     case elfcpp::R_X86_64_GOTPCREL64:
2130     case elfcpp::R_X86_64_GOTPCREL:
2131     case elfcpp::R_X86_64_GOTPLT64:
2132       // Absolute in GOT.
2133       return Symbol::ABSOLUTE_REF;
2134
2135     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2136     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2137     case elfcpp::R_X86_64_TLSDESC_CALL:
2138     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2139     case elfcpp::R_X86_64_DTPOFF32:
2140     case elfcpp::R_X86_64_DTPOFF64:
2141     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2142     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2143       return Symbol::TLS_REF;
2144
2145     case elfcpp::R_X86_64_COPY:
2146     case elfcpp::R_X86_64_GLOB_DAT:
2147     case elfcpp::R_X86_64_JUMP_SLOT:
2148     case elfcpp::R_X86_64_RELATIVE:
2149     case elfcpp::R_X86_64_IRELATIVE:
2150     case elfcpp::R_X86_64_TPOFF64:
2151     case elfcpp::R_X86_64_DTPMOD64:
2152     case elfcpp::R_X86_64_TLSDESC:
2153     case elfcpp::R_X86_64_SIZE32:
2154     case elfcpp::R_X86_64_SIZE64:
2155     default:
2156       // Not expected.  We will give an error later.
2157       return 0;
2158     }
2159 }
2160
2161 // Report an unsupported relocation against a local symbol.
2162
2163 template<int size>
2164 void
2165 Target_x86_64<size>::Scan::unsupported_reloc_local(
2166      Sized_relobj_file<size, false>* object,
2167      unsigned int r_type)
2168 {
2169   gold_error(_("%s: unsupported reloc %u against local symbol"),
2170              object->name().c_str(), r_type);
2171 }
2172
2173 // We are about to emit a dynamic relocation of type R_TYPE.  If the
2174 // dynamic linker does not support it, issue an error.  The GNU linker
2175 // only issues a non-PIC error for an allocated read-only section.
2176 // Here we know the section is allocated, but we don't know that it is
2177 // read-only.  But we check for all the relocation types which the
2178 // glibc dynamic linker supports, so it seems appropriate to issue an
2179 // error even if the section is not read-only.  If GSYM is not NULL,
2180 // it is the symbol the relocation is against; if it is NULL, the
2181 // relocation is against a local symbol.
2182
2183 template<int size>
2184 void
2185 Target_x86_64<size>::Scan::check_non_pic(Relobj* object, unsigned int r_type,
2186                                          Symbol* gsym)
2187 {
2188   switch (r_type)
2189     {
2190       // These are the relocation types supported by glibc for x86_64
2191       // which should always work.
2192     case elfcpp::R_X86_64_RELATIVE:
2193     case elfcpp::R_X86_64_IRELATIVE:
2194     case elfcpp::R_X86_64_GLOB_DAT:
2195     case elfcpp::R_X86_64_JUMP_SLOT:
2196     case elfcpp::R_X86_64_DTPMOD64:
2197     case elfcpp::R_X86_64_DTPOFF64:
2198     case elfcpp::R_X86_64_TPOFF64:
2199     case elfcpp::R_X86_64_64:
2200     case elfcpp::R_X86_64_COPY:
2201       return;
2202
2203       // glibc supports these reloc types, but they can overflow.
2204     case elfcpp::R_X86_64_PC32:
2205       // A PC relative reference is OK against a local symbol or if
2206       // the symbol is defined locally.
2207       if (gsym == NULL
2208           || (!gsym->is_from_dynobj()
2209               && !gsym->is_undefined()
2210               && !gsym->is_preemptible()))
2211         return;
2212       /* Fall through.  */
2213     case elfcpp::R_X86_64_32:
2214       // R_X86_64_32 is OK for x32.
2215       if (size == 32 && r_type == elfcpp::R_X86_64_32)
2216         return;
2217       if (this->issued_non_pic_error_)
2218         return;
2219       gold_assert(parameters->options().output_is_position_independent());
2220       if (gsym == NULL)
2221         object->error(_("requires dynamic R_X86_64_32 reloc which may "
2222                         "overflow at runtime; recompile with -fPIC"));
2223       else
2224         object->error(_("requires dynamic %s reloc against '%s' which may "
2225                         "overflow at runtime; recompile with -fPIC"),
2226                       (r_type == elfcpp::R_X86_64_32
2227                        ? "R_X86_64_32"
2228                        : "R_X86_64_PC32"),
2229                       gsym->name());
2230       this->issued_non_pic_error_ = true;
2231       return;
2232
2233     default:
2234       // This prevents us from issuing more than one error per reloc
2235       // section.  But we can still wind up issuing more than one
2236       // error per object file.
2237       if (this->issued_non_pic_error_)
2238         return;
2239       gold_assert(parameters->options().output_is_position_independent());
2240       object->error(_("requires unsupported dynamic reloc %u; "
2241                       "recompile with -fPIC"),
2242                     r_type);
2243       this->issued_non_pic_error_ = true;
2244       return;
2245
2246     case elfcpp::R_X86_64_NONE:
2247       gold_unreachable();
2248     }
2249 }
2250
2251 // Return whether we need to make a PLT entry for a relocation of the
2252 // given type against a STT_GNU_IFUNC symbol.
2253
2254 template<int size>
2255 bool
2256 Target_x86_64<size>::Scan::reloc_needs_plt_for_ifunc(
2257      Sized_relobj_file<size, false>* object,
2258      unsigned int r_type)
2259 {
2260   int flags = Scan::get_reference_flags(r_type);
2261   if (flags & Symbol::TLS_REF)
2262     gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2263                object->name().c_str(), r_type);
2264   return flags != 0;
2265 }
2266
2267 // Scan a relocation for a local symbol.
2268
2269 template<int size>
2270 inline void
2271 Target_x86_64<size>::Scan::local(Symbol_table* symtab,
2272                                  Layout* layout,
2273                                  Target_x86_64<size>* target,
2274                                  Sized_relobj_file<size, false>* object,
2275                                  unsigned int data_shndx,
2276                                  Output_section* output_section,
2277                                  const elfcpp::Rela<size, false>& reloc,
2278                                  unsigned int r_type,
2279                                  const elfcpp::Sym<size, false>& lsym,
2280                                  bool is_discarded)
2281 {
2282   if (is_discarded)
2283     return;
2284
2285   // A local STT_GNU_IFUNC symbol may require a PLT entry.
2286   bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
2287   if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
2288     {
2289       unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2290       target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
2291     }
2292
2293   switch (r_type)
2294     {
2295     case elfcpp::R_X86_64_NONE:
2296     case elfcpp::R_X86_64_GNU_VTINHERIT:
2297     case elfcpp::R_X86_64_GNU_VTENTRY:
2298       break;
2299
2300     case elfcpp::R_X86_64_64:
2301       // If building a shared library (or a position-independent
2302       // executable), we need to create a dynamic relocation for this
2303       // location.  The relocation applied at link time will apply the
2304       // link-time value, so we flag the location with an
2305       // R_X86_64_RELATIVE relocation so the dynamic loader can
2306       // relocate it easily.
2307       if (parameters->options().output_is_position_independent())
2308         {
2309           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2310           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2311           rela_dyn->add_local_relative(object, r_sym,
2312                                        (size == 32
2313                                         ? elfcpp::R_X86_64_RELATIVE64
2314                                         : elfcpp::R_X86_64_RELATIVE),
2315                                        output_section, data_shndx,
2316                                        reloc.get_r_offset(),
2317                                        reloc.get_r_addend(), is_ifunc);
2318         }
2319       break;
2320
2321     case elfcpp::R_X86_64_32:
2322     case elfcpp::R_X86_64_32S:
2323     case elfcpp::R_X86_64_16:
2324     case elfcpp::R_X86_64_8:
2325       // If building a shared library (or a position-independent
2326       // executable), we need to create a dynamic relocation for this
2327       // location.  We can't use an R_X86_64_RELATIVE relocation
2328       // because that is always a 64-bit relocation.
2329       if (parameters->options().output_is_position_independent())
2330         {
2331           // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
2332           if (size == 32 && r_type == elfcpp::R_X86_64_32)
2333             {
2334               unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2335               Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2336               rela_dyn->add_local_relative(object, r_sym,
2337                                            elfcpp::R_X86_64_RELATIVE,
2338                                            output_section, data_shndx,
2339                                            reloc.get_r_offset(),
2340                                            reloc.get_r_addend(), is_ifunc);
2341               break;
2342             }
2343
2344           this->check_non_pic(object, r_type, NULL);
2345
2346           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2347           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2348           if (lsym.get_st_type() != elfcpp::STT_SECTION)
2349             rela_dyn->add_local(object, r_sym, r_type, output_section,
2350                                 data_shndx, reloc.get_r_offset(),
2351                                 reloc.get_r_addend());
2352           else
2353             {
2354               gold_assert(lsym.get_st_value() == 0);
2355               unsigned int shndx = lsym.get_st_shndx();
2356               bool is_ordinary;
2357               shndx = object->adjust_sym_shndx(r_sym, shndx,
2358                                                &is_ordinary);
2359               if (!is_ordinary)
2360                 object->error(_("section symbol %u has bad shndx %u"),
2361                               r_sym, shndx);
2362               else
2363                 rela_dyn->add_local_section(object, shndx,
2364                                             r_type, output_section,
2365                                             data_shndx, reloc.get_r_offset(),
2366                                             reloc.get_r_addend());
2367             }
2368         }
2369       break;
2370
2371     case elfcpp::R_X86_64_PC64:
2372     case elfcpp::R_X86_64_PC32:
2373     case elfcpp::R_X86_64_PC16:
2374     case elfcpp::R_X86_64_PC8:
2375       break;
2376
2377     case elfcpp::R_X86_64_PLT32:
2378       // Since we know this is a local symbol, we can handle this as a
2379       // PC32 reloc.
2380       break;
2381
2382     case elfcpp::R_X86_64_GOTPC32:
2383     case elfcpp::R_X86_64_GOTOFF64:
2384     case elfcpp::R_X86_64_GOTPC64:
2385     case elfcpp::R_X86_64_PLTOFF64:
2386       // We need a GOT section.
2387       target->got_section(symtab, layout);
2388       // For PLTOFF64, we'd normally want a PLT section, but since we
2389       // know this is a local symbol, no PLT is needed.
2390       break;
2391
2392     case elfcpp::R_X86_64_GOT64:
2393     case elfcpp::R_X86_64_GOT32:
2394     case elfcpp::R_X86_64_GOTPCREL64:
2395     case elfcpp::R_X86_64_GOTPCREL:
2396     case elfcpp::R_X86_64_GOTPLT64:
2397       {
2398         // The symbol requires a GOT entry.
2399         Output_data_got<64, false>* got = target->got_section(symtab, layout);
2400         unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2401
2402         // For a STT_GNU_IFUNC symbol we want the PLT offset.  That
2403         // lets function pointers compare correctly with shared
2404         // libraries.  Otherwise we would need an IRELATIVE reloc.
2405         bool is_new;
2406         if (is_ifunc)
2407           is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
2408         else
2409           is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
2410         if (is_new)
2411           {
2412             // If we are generating a shared object, we need to add a
2413             // dynamic relocation for this symbol's GOT entry.
2414             if (parameters->options().output_is_position_independent())
2415               {
2416                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2417                 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2418                 if (r_type != elfcpp::R_X86_64_GOT32)
2419                   {
2420                     unsigned int got_offset =
2421                       object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
2422                     rela_dyn->add_local_relative(object, r_sym,
2423                                                  elfcpp::R_X86_64_RELATIVE,
2424                                                  got, got_offset, 0, is_ifunc);
2425                   }
2426                 else
2427                   {
2428                     this->check_non_pic(object, r_type, NULL);
2429
2430                     gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2431                     rela_dyn->add_local(
2432                         object, r_sym, r_type, got,
2433                         object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
2434                   }
2435               }
2436           }
2437         // For GOTPLT64, we'd normally want a PLT section, but since
2438         // we know this is a local symbol, no PLT is needed.
2439       }
2440       break;
2441
2442     case elfcpp::R_X86_64_COPY:
2443     case elfcpp::R_X86_64_GLOB_DAT:
2444     case elfcpp::R_X86_64_JUMP_SLOT:
2445     case elfcpp::R_X86_64_RELATIVE:
2446     case elfcpp::R_X86_64_IRELATIVE:
2447       // These are outstanding tls relocs, which are unexpected when linking
2448     case elfcpp::R_X86_64_TPOFF64:
2449     case elfcpp::R_X86_64_DTPMOD64:
2450     case elfcpp::R_X86_64_TLSDESC:
2451       gold_error(_("%s: unexpected reloc %u in object file"),
2452                  object->name().c_str(), r_type);
2453       break;
2454
2455       // These are initial tls relocs, which are expected when linking
2456     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2457     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2458     case elfcpp::R_X86_64_TLSDESC_CALL:
2459     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2460     case elfcpp::R_X86_64_DTPOFF32:
2461     case elfcpp::R_X86_64_DTPOFF64:
2462     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2463     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2464       {
2465         bool output_is_shared = parameters->options().shared();
2466         const tls::Tls_optimization optimized_type
2467             = Target_x86_64<size>::optimize_tls_reloc(!output_is_shared,
2468                                                       r_type);
2469         switch (r_type)
2470           {
2471           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
2472             if (optimized_type == tls::TLSOPT_NONE)
2473               {
2474                 // Create a pair of GOT entries for the module index and
2475                 // dtv-relative offset.
2476                 Output_data_got<64, false>* got
2477                     = target->got_section(symtab, layout);
2478                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2479                 unsigned int shndx = lsym.get_st_shndx();
2480                 bool is_ordinary;
2481                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
2482                 if (!is_ordinary)
2483                   object->error(_("local symbol %u has bad shndx %u"),
2484                               r_sym, shndx);
2485                 else
2486                   got->add_local_pair_with_rel(object, r_sym,
2487                                                shndx,
2488                                                GOT_TYPE_TLS_PAIR,
2489                                                target->rela_dyn_section(layout),
2490                                                elfcpp::R_X86_64_DTPMOD64);
2491               }
2492             else if (optimized_type != tls::TLSOPT_TO_LE)
2493               unsupported_reloc_local(object, r_type);
2494             break;
2495
2496           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2497             target->define_tls_base_symbol(symtab, layout);
2498             if (optimized_type == tls::TLSOPT_NONE)
2499               {
2500                 // Create reserved PLT and GOT entries for the resolver.
2501                 target->reserve_tlsdesc_entries(symtab, layout);
2502
2503                 // Generate a double GOT entry with an
2504                 // R_X86_64_TLSDESC reloc.  The R_X86_64_TLSDESC reloc
2505                 // is resolved lazily, so the GOT entry needs to be in
2506                 // an area in .got.plt, not .got.  Call got_section to
2507                 // make sure the section has been created.
2508                 target->got_section(symtab, layout);
2509                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2510                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2511                 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
2512                   {
2513                     unsigned int got_offset = got->add_constant(0);
2514                     got->add_constant(0);
2515                     object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
2516                                                  got_offset);
2517                     Reloc_section* rt = target->rela_tlsdesc_section(layout);
2518                     // We store the arguments we need in a vector, and
2519                     // use the index into the vector as the parameter
2520                     // to pass to the target specific routines.
2521                     uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
2522                     void* arg = reinterpret_cast<void*>(intarg);
2523                     rt->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
2524                                             got, got_offset, 0);
2525                   }
2526               }
2527             else if (optimized_type != tls::TLSOPT_TO_LE)
2528               unsupported_reloc_local(object, r_type);
2529             break;
2530
2531           case elfcpp::R_X86_64_TLSDESC_CALL:
2532             break;
2533
2534           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
2535             if (optimized_type == tls::TLSOPT_NONE)
2536               {
2537                 // Create a GOT entry for the module index.
2538                 target->got_mod_index_entry(symtab, layout, object);
2539               }
2540             else if (optimized_type != tls::TLSOPT_TO_LE)
2541               unsupported_reloc_local(object, r_type);
2542             break;
2543
2544           case elfcpp::R_X86_64_DTPOFF32:
2545           case elfcpp::R_X86_64_DTPOFF64:
2546             break;
2547
2548           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
2549             layout->set_has_static_tls();
2550             if (optimized_type == tls::TLSOPT_NONE)
2551               {
2552                 // Create a GOT entry for the tp-relative offset.
2553                 Output_data_got<64, false>* got
2554                     = target->got_section(symtab, layout);
2555                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2556                 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
2557                                         target->rela_dyn_section(layout),
2558                                         elfcpp::R_X86_64_TPOFF64);
2559               }
2560             else if (optimized_type != tls::TLSOPT_TO_LE)
2561               unsupported_reloc_local(object, r_type);
2562             break;
2563
2564           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
2565             layout->set_has_static_tls();
2566             if (output_is_shared)
2567               unsupported_reloc_local(object, r_type);
2568             break;
2569
2570           default:
2571             gold_unreachable();
2572           }
2573       }
2574       break;
2575
2576     case elfcpp::R_X86_64_SIZE32:
2577     case elfcpp::R_X86_64_SIZE64:
2578     default:
2579       gold_error(_("%s: unsupported reloc %u against local symbol"),
2580                  object->name().c_str(), r_type);
2581       break;
2582     }
2583 }
2584
2585
2586 // Report an unsupported relocation against a global symbol.
2587
2588 template<int size>
2589 void
2590 Target_x86_64<size>::Scan::unsupported_reloc_global(
2591     Sized_relobj_file<size, false>* object,
2592     unsigned int r_type,
2593     Symbol* gsym)
2594 {
2595   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2596              object->name().c_str(), r_type, gsym->demangled_name().c_str());
2597 }
2598
2599 // Returns true if this relocation type could be that of a function pointer.
2600 template<int size>
2601 inline bool
2602 Target_x86_64<size>::Scan::possible_function_pointer_reloc(unsigned int r_type)
2603 {
2604   switch (r_type)
2605     {
2606     case elfcpp::R_X86_64_64:
2607     case elfcpp::R_X86_64_32:
2608     case elfcpp::R_X86_64_32S:
2609     case elfcpp::R_X86_64_16:
2610     case elfcpp::R_X86_64_8:
2611     case elfcpp::R_X86_64_GOT64:
2612     case elfcpp::R_X86_64_GOT32:
2613     case elfcpp::R_X86_64_GOTPCREL64:
2614     case elfcpp::R_X86_64_GOTPCREL:
2615     case elfcpp::R_X86_64_GOTPLT64:
2616       {
2617         return true;
2618       }
2619     }
2620   return false;
2621 }
2622
2623 // For safe ICF, scan a relocation for a local symbol to check if it
2624 // corresponds to a function pointer being taken.  In that case mark
2625 // the function whose pointer was taken as not foldable.
2626
2627 template<int size>
2628 inline bool
2629 Target_x86_64<size>::Scan::local_reloc_may_be_function_pointer(
2630   Symbol_table* ,
2631   Layout* ,
2632   Target_x86_64<size>* ,
2633   Sized_relobj_file<size, false>* ,
2634   unsigned int ,
2635   Output_section* ,
2636   const elfcpp::Rela<size, false>& ,
2637   unsigned int r_type,
2638   const elfcpp::Sym<size, false>&)
2639 {
2640   // When building a shared library, do not fold any local symbols as it is
2641   // not possible to distinguish pointer taken versus a call by looking at
2642   // the relocation types.
2643   return (parameters->options().shared()
2644           || possible_function_pointer_reloc(r_type));
2645 }
2646
2647 // For safe ICF, scan a relocation for a global symbol to check if it
2648 // corresponds to a function pointer being taken.  In that case mark
2649 // the function whose pointer was taken as not foldable.
2650
2651 template<int size>
2652 inline bool
2653 Target_x86_64<size>::Scan::global_reloc_may_be_function_pointer(
2654   Symbol_table*,
2655   Layout* ,
2656   Target_x86_64<size>* ,
2657   Sized_relobj_file<size, false>* ,
2658   unsigned int ,
2659   Output_section* ,
2660   const elfcpp::Rela<size, false>& ,
2661   unsigned int r_type,
2662   Symbol* gsym)
2663 {
2664   // When building a shared library, do not fold symbols whose visibility
2665   // is hidden, internal or protected.
2666   return ((parameters->options().shared()
2667            && (gsym->visibility() == elfcpp::STV_INTERNAL
2668                || gsym->visibility() == elfcpp::STV_PROTECTED
2669                || gsym->visibility() == elfcpp::STV_HIDDEN))
2670           || possible_function_pointer_reloc(r_type));
2671 }
2672
2673 // Scan a relocation for a global symbol.
2674
2675 template<int size>
2676 inline void
2677 Target_x86_64<size>::Scan::global(Symbol_table* symtab,
2678                             Layout* layout,
2679                             Target_x86_64<size>* target,
2680                             Sized_relobj_file<size, false>* object,
2681                             unsigned int data_shndx,
2682                             Output_section* output_section,
2683                             const elfcpp::Rela<size, false>& reloc,
2684                             unsigned int r_type,
2685                             Symbol* gsym)
2686 {
2687   // A STT_GNU_IFUNC symbol may require a PLT entry.
2688   if (gsym->type() == elfcpp::STT_GNU_IFUNC
2689       && this->reloc_needs_plt_for_ifunc(object, r_type))
2690     target->make_plt_entry(symtab, layout, gsym);
2691
2692   switch (r_type)
2693     {
2694     case elfcpp::R_X86_64_NONE:
2695     case elfcpp::R_X86_64_GNU_VTINHERIT:
2696     case elfcpp::R_X86_64_GNU_VTENTRY:
2697       break;
2698
2699     case elfcpp::R_X86_64_64:
2700     case elfcpp::R_X86_64_32:
2701     case elfcpp::R_X86_64_32S:
2702     case elfcpp::R_X86_64_16:
2703     case elfcpp::R_X86_64_8:
2704       {
2705         // Make a PLT entry if necessary.
2706         if (gsym->needs_plt_entry())
2707           {
2708             target->make_plt_entry(symtab, layout, gsym);
2709             // Since this is not a PC-relative relocation, we may be
2710             // taking the address of a function. In that case we need to
2711             // set the entry in the dynamic symbol table to the address of
2712             // the PLT entry.
2713             if (gsym->is_from_dynobj() && !parameters->options().shared())
2714               gsym->set_needs_dynsym_value();
2715           }
2716         // Make a dynamic relocation if necessary.
2717         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2718           {
2719             if (gsym->may_need_copy_reloc())
2720               {
2721                 target->copy_reloc(symtab, layout, object,
2722                                    data_shndx, output_section, gsym, reloc);
2723               }
2724             else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2725                       || (size == 32 && r_type == elfcpp::R_X86_64_32))
2726                      && gsym->type() == elfcpp::STT_GNU_IFUNC
2727                      && gsym->can_use_relative_reloc(false)
2728                      && !gsym->is_from_dynobj()
2729                      && !gsym->is_undefined()
2730                      && !gsym->is_preemptible())
2731               {
2732                 // Use an IRELATIVE reloc for a locally defined
2733                 // STT_GNU_IFUNC symbol.  This makes a function
2734                 // address in a PIE executable match the address in a
2735                 // shared library that it links against.
2736                 Reloc_section* rela_dyn =
2737                   target->rela_irelative_section(layout);
2738                 unsigned int r_type = elfcpp::R_X86_64_IRELATIVE;
2739                 rela_dyn->add_symbolless_global_addend(gsym, r_type,
2740                                                        output_section, object,
2741                                                        data_shndx,
2742                                                        reloc.get_r_offset(),
2743                                                        reloc.get_r_addend());
2744               }
2745             else if (r_type == elfcpp::R_X86_64_64
2746                      && gsym->can_use_relative_reloc(false))
2747               {
2748                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2749                 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
2750                                               output_section, object,
2751                                               data_shndx,
2752                                               reloc.get_r_offset(),
2753                                               reloc.get_r_addend(), false);
2754               }
2755             else
2756               {
2757                 this->check_non_pic(object, r_type, gsym);
2758                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2759                 rela_dyn->add_global(gsym, r_type, output_section, object,
2760                                      data_shndx, reloc.get_r_offset(),
2761                                      reloc.get_r_addend());
2762               }
2763           }
2764       }
2765       break;
2766
2767     case elfcpp::R_X86_64_PC64:
2768     case elfcpp::R_X86_64_PC32:
2769     case elfcpp::R_X86_64_PC16:
2770     case elfcpp::R_X86_64_PC8:
2771       {
2772         // Make a PLT entry if necessary.
2773         if (gsym->needs_plt_entry())
2774           target->make_plt_entry(symtab, layout, gsym);
2775         // Make a dynamic relocation if necessary.
2776         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2777           {
2778             if (gsym->may_need_copy_reloc())
2779               {
2780                 target->copy_reloc(symtab, layout, object,
2781                                    data_shndx, output_section, gsym, reloc);
2782               }
2783             else
2784               {
2785                 this->check_non_pic(object, r_type, gsym);
2786                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2787                 rela_dyn->add_global(gsym, r_type, output_section, object,
2788                                      data_shndx, reloc.get_r_offset(),
2789                                      reloc.get_r_addend());
2790               }
2791           }
2792       }
2793       break;
2794
2795     case elfcpp::R_X86_64_GOT64:
2796     case elfcpp::R_X86_64_GOT32:
2797     case elfcpp::R_X86_64_GOTPCREL64:
2798     case elfcpp::R_X86_64_GOTPCREL:
2799     case elfcpp::R_X86_64_GOTPLT64:
2800       {
2801         // The symbol requires a GOT entry.
2802         Output_data_got<64, false>* got = target->got_section(symtab, layout);
2803         if (gsym->final_value_is_known())
2804           {
2805             // For a STT_GNU_IFUNC symbol we want the PLT address.
2806             if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2807               got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2808             else
2809               got->add_global(gsym, GOT_TYPE_STANDARD);
2810           }
2811         else
2812           {
2813             // If this symbol is not fully resolved, we need to add a
2814             // dynamic relocation for it.
2815             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2816
2817             // Use a GLOB_DAT rather than a RELATIVE reloc if:
2818             //
2819             // 1) The symbol may be defined in some other module.
2820             //
2821             // 2) We are building a shared library and this is a
2822             // protected symbol; using GLOB_DAT means that the dynamic
2823             // linker can use the address of the PLT in the main
2824             // executable when appropriate so that function address
2825             // comparisons work.
2826             //
2827             // 3) This is a STT_GNU_IFUNC symbol in position dependent
2828             // code, again so that function address comparisons work.
2829             if (gsym->is_from_dynobj()
2830                 || gsym->is_undefined()
2831                 || gsym->is_preemptible()
2832                 || (gsym->visibility() == elfcpp::STV_PROTECTED
2833                     && parameters->options().shared())
2834                 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2835                     && parameters->options().output_is_position_independent()))
2836               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, rela_dyn,
2837                                        elfcpp::R_X86_64_GLOB_DAT);
2838             else
2839               {
2840                 // For a STT_GNU_IFUNC symbol we want to write the PLT
2841                 // offset into the GOT, so that function pointer
2842                 // comparisons work correctly.
2843                 bool is_new;
2844                 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2845                   is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2846                 else
2847                   {
2848                     is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2849                     // Tell the dynamic linker to use the PLT address
2850                     // when resolving relocations.
2851                     if (gsym->is_from_dynobj()
2852                         && !parameters->options().shared())
2853                       gsym->set_needs_dynsym_value();
2854                   }
2855                 if (is_new)
2856                   {
2857                     unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2858                     rela_dyn->add_global_relative(gsym,
2859                                                   elfcpp::R_X86_64_RELATIVE,
2860                                                   got, got_off, 0, false);
2861                   }
2862               }
2863           }
2864         // For GOTPLT64, we also need a PLT entry (but only if the
2865         // symbol is not fully resolved).
2866         if (r_type == elfcpp::R_X86_64_GOTPLT64
2867             && !gsym->final_value_is_known())
2868           target->make_plt_entry(symtab, layout, gsym);
2869       }
2870       break;
2871
2872     case elfcpp::R_X86_64_PLT32:
2873       // If the symbol is fully resolved, this is just a PC32 reloc.
2874       // Otherwise we need a PLT entry.
2875       if (gsym->final_value_is_known())
2876         break;
2877       // If building a shared library, we can also skip the PLT entry
2878       // if the symbol is defined in the output file and is protected
2879       // or hidden.
2880       if (gsym->is_defined()
2881           && !gsym->is_from_dynobj()
2882           && !gsym->is_preemptible())
2883         break;
2884       target->make_plt_entry(symtab, layout, gsym);
2885       break;
2886
2887     case elfcpp::R_X86_64_GOTPC32:
2888     case elfcpp::R_X86_64_GOTOFF64:
2889     case elfcpp::R_X86_64_GOTPC64:
2890     case elfcpp::R_X86_64_PLTOFF64:
2891       // We need a GOT section.
2892       target->got_section(symtab, layout);
2893       // For PLTOFF64, we also need a PLT entry (but only if the
2894       // symbol is not fully resolved).
2895       if (r_type == elfcpp::R_X86_64_PLTOFF64
2896           && !gsym->final_value_is_known())
2897         target->make_plt_entry(symtab, layout, gsym);
2898       break;
2899
2900     case elfcpp::R_X86_64_COPY:
2901     case elfcpp::R_X86_64_GLOB_DAT:
2902     case elfcpp::R_X86_64_JUMP_SLOT:
2903     case elfcpp::R_X86_64_RELATIVE:
2904     case elfcpp::R_X86_64_IRELATIVE:
2905       // These are outstanding tls relocs, which are unexpected when linking
2906     case elfcpp::R_X86_64_TPOFF64:
2907     case elfcpp::R_X86_64_DTPMOD64:
2908     case elfcpp::R_X86_64_TLSDESC:
2909       gold_error(_("%s: unexpected reloc %u in object file"),
2910                  object->name().c_str(), r_type);
2911       break;
2912
2913       // These are initial tls relocs, which are expected for global()
2914     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2915     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2916     case elfcpp::R_X86_64_TLSDESC_CALL:
2917     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2918     case elfcpp::R_X86_64_DTPOFF32:
2919     case elfcpp::R_X86_64_DTPOFF64:
2920     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2921     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2922       {
2923         const bool is_final = gsym->final_value_is_known();
2924         const tls::Tls_optimization optimized_type
2925             = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
2926         switch (r_type)
2927           {
2928           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
2929             if (optimized_type == tls::TLSOPT_NONE)
2930               {
2931                 // Create a pair of GOT entries for the module index and
2932                 // dtv-relative offset.
2933                 Output_data_got<64, false>* got
2934                     = target->got_section(symtab, layout);
2935                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2936                                               target->rela_dyn_section(layout),
2937                                               elfcpp::R_X86_64_DTPMOD64,
2938                                               elfcpp::R_X86_64_DTPOFF64);
2939               }
2940             else if (optimized_type == tls::TLSOPT_TO_IE)
2941               {
2942                 // Create a GOT entry for the tp-relative offset.
2943                 Output_data_got<64, false>* got
2944                     = target->got_section(symtab, layout);
2945                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2946                                          target->rela_dyn_section(layout),
2947                                          elfcpp::R_X86_64_TPOFF64);
2948               }
2949             else if (optimized_type != tls::TLSOPT_TO_LE)
2950               unsupported_reloc_global(object, r_type, gsym);
2951             break;
2952
2953           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2954             target->define_tls_base_symbol(symtab, layout);
2955             if (optimized_type == tls::TLSOPT_NONE)
2956               {
2957                 // Create reserved PLT and GOT entries for the resolver.
2958                 target->reserve_tlsdesc_entries(symtab, layout);
2959
2960                 // Create a double GOT entry with an R_X86_64_TLSDESC
2961                 // reloc.  The R_X86_64_TLSDESC reloc is resolved
2962                 // lazily, so the GOT entry needs to be in an area in
2963                 // .got.plt, not .got.  Call got_section to make sure
2964                 // the section has been created.
2965                 target->got_section(symtab, layout);
2966                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2967                 Reloc_section* rt = target->rela_tlsdesc_section(layout);
2968                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2969                                               elfcpp::R_X86_64_TLSDESC, 0);
2970               }
2971             else if (optimized_type == tls::TLSOPT_TO_IE)
2972               {
2973                 // Create a GOT entry for the tp-relative offset.
2974                 Output_data_got<64, false>* got
2975                     = target->got_section(symtab, layout);
2976                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2977                                          target->rela_dyn_section(layout),
2978                                          elfcpp::R_X86_64_TPOFF64);
2979               }
2980             else if (optimized_type != tls::TLSOPT_TO_LE)
2981               unsupported_reloc_global(object, r_type, gsym);
2982             break;
2983
2984           case elfcpp::R_X86_64_TLSDESC_CALL:
2985             break;
2986
2987           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
2988             if (optimized_type == tls::TLSOPT_NONE)
2989               {
2990                 // Create a GOT entry for the module index.
2991                 target->got_mod_index_entry(symtab, layout, object);
2992               }
2993             else if (optimized_type != tls::TLSOPT_TO_LE)
2994               unsupported_reloc_global(object, r_type, gsym);
2995             break;
2996
2997           case elfcpp::R_X86_64_DTPOFF32:
2998           case elfcpp::R_X86_64_DTPOFF64:
2999             break;
3000
3001           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
3002             layout->set_has_static_tls();
3003             if (optimized_type == tls::TLSOPT_NONE)
3004               {
3005                 // Create a GOT entry for the tp-relative offset.
3006                 Output_data_got<64, false>* got
3007                     = target->got_section(symtab, layout);
3008                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
3009                                          target->rela_dyn_section(layout),
3010                                          elfcpp::R_X86_64_TPOFF64);
3011               }
3012             else if (optimized_type != tls::TLSOPT_TO_LE)
3013               unsupported_reloc_global(object, r_type, gsym);
3014             break;
3015
3016           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
3017             layout->set_has_static_tls();
3018             if (parameters->options().shared())
3019               unsupported_reloc_global(object, r_type, gsym);
3020             break;
3021
3022           default:
3023             gold_unreachable();
3024           }
3025       }
3026       break;
3027
3028     case elfcpp::R_X86_64_SIZE32:
3029     case elfcpp::R_X86_64_SIZE64:
3030     default:
3031       gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3032                  object->name().c_str(), r_type,
3033                  gsym->demangled_name().c_str());
3034       break;
3035     }
3036 }
3037
3038 template<int size>
3039 void
3040 Target_x86_64<size>::gc_process_relocs(Symbol_table* symtab,
3041                                        Layout* layout,
3042                                        Sized_relobj_file<size, false>* object,
3043                                        unsigned int data_shndx,
3044                                        unsigned int sh_type,
3045                                        const unsigned char* prelocs,
3046                                        size_t reloc_count,
3047                                        Output_section* output_section,
3048                                        bool needs_special_offset_handling,
3049                                        size_t local_symbol_count,
3050                                        const unsigned char* plocal_symbols)
3051 {
3052
3053   if (sh_type == elfcpp::SHT_REL)
3054     {
3055       return;
3056     }
3057
3058    gold::gc_process_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3059                            typename Target_x86_64<size>::Scan,
3060                            typename Target_x86_64<size>::Relocatable_size_for_reloc>(
3061     symtab,
3062     layout,
3063     this,
3064     object,
3065     data_shndx,
3066     prelocs,
3067     reloc_count,
3068     output_section,
3069     needs_special_offset_handling,
3070     local_symbol_count,
3071     plocal_symbols);
3072
3073 }
3074 // Scan relocations for a section.
3075
3076 template<int size>
3077 void
3078 Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
3079                                  Layout* layout,
3080                                  Sized_relobj_file<size, false>* object,
3081                                  unsigned int data_shndx,
3082                                  unsigned int sh_type,
3083                                  const unsigned char* prelocs,
3084                                  size_t reloc_count,
3085                                  Output_section* output_section,
3086                                  bool needs_special_offset_handling,
3087                                  size_t local_symbol_count,
3088                                  const unsigned char* plocal_symbols)
3089 {
3090   if (sh_type == elfcpp::SHT_REL)
3091     {
3092       gold_error(_("%s: unsupported REL reloc section"),
3093                  object->name().c_str());
3094       return;
3095     }
3096
3097   gold::scan_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3098       typename Target_x86_64<size>::Scan>(
3099     symtab,
3100     layout,
3101     this,
3102     object,
3103     data_shndx,
3104     prelocs,
3105     reloc_count,
3106     output_section,
3107     needs_special_offset_handling,
3108     local_symbol_count,
3109     plocal_symbols);
3110 }
3111
3112 // Finalize the sections.
3113
3114 template<int size>
3115 void
3116 Target_x86_64<size>::do_finalize_sections(
3117     Layout* layout,
3118     const Input_objects*,
3119     Symbol_table* symtab)
3120 {
3121   const Reloc_section* rel_plt = (this->plt_ == NULL
3122                                   ? NULL
3123                                   : this->plt_->rela_plt());
3124   layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
3125                                   this->rela_dyn_, true, false);
3126
3127   // Fill in some more dynamic tags.
3128   Output_data_dynamic* const odyn = layout->dynamic_data();
3129   if (odyn != NULL)
3130     {
3131       if (this->plt_ != NULL
3132           && this->plt_->output_section() != NULL
3133           && this->plt_->has_tlsdesc_entry())
3134         {
3135           unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
3136           unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
3137           this->got_->finalize_data_size();
3138           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
3139                                         this->plt_, plt_offset);
3140           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
3141                                         this->got_, got_offset);
3142         }
3143     }
3144
3145   // Emit any relocs we saved in an attempt to avoid generating COPY
3146   // relocs.
3147   if (this->copy_relocs_.any_saved_relocs())
3148     this->copy_relocs_.emit(this->rela_dyn_section(layout));
3149
3150   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
3151   // the .got.plt section.
3152   Symbol* sym = this->global_offset_table_;
3153   if (sym != NULL)
3154     {
3155       uint64_t data_size = this->got_plt_->current_data_size();
3156       symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
3157     }
3158
3159   if (parameters->doing_static_link()
3160       && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
3161     {
3162       // If linking statically, make sure that the __rela_iplt symbols
3163       // were defined if necessary, even if we didn't create a PLT.
3164       static const Define_symbol_in_segment syms[] =
3165         {
3166           {
3167             "__rela_iplt_start",        // name
3168             elfcpp::PT_LOAD,            // segment_type
3169             elfcpp::PF_W,               // segment_flags_set
3170             elfcpp::PF(0),              // segment_flags_clear
3171             0,                          // value
3172             0,                          // size
3173             elfcpp::STT_NOTYPE,         // type
3174             elfcpp::STB_GLOBAL,         // binding
3175             elfcpp::STV_HIDDEN,         // visibility
3176             0,                          // nonvis
3177             Symbol::SEGMENT_START,      // offset_from_base
3178             true                        // only_if_ref
3179           },
3180           {
3181             "__rela_iplt_end",          // name
3182             elfcpp::PT_LOAD,            // segment_type
3183             elfcpp::PF_W,               // segment_flags_set
3184             elfcpp::PF(0),              // segment_flags_clear
3185             0,                          // value
3186             0,                          // size
3187             elfcpp::STT_NOTYPE,         // type
3188             elfcpp::STB_GLOBAL,         // binding
3189             elfcpp::STV_HIDDEN,         // visibility
3190             0,                          // nonvis
3191             Symbol::SEGMENT_START,      // offset_from_base
3192             true                        // only_if_ref
3193           }
3194         };
3195
3196       symtab->define_symbols(layout, 2, syms,
3197                              layout->script_options()->saw_sections_clause());
3198     }
3199 }
3200
3201 // Perform a relocation.
3202
3203 template<int size>
3204 inline bool
3205 Target_x86_64<size>::Relocate::relocate(
3206     const Relocate_info<size, false>* relinfo,
3207     Target_x86_64<size>* target,
3208     Output_section*,
3209     size_t relnum,
3210     const elfcpp::Rela<size, false>& rela,
3211     unsigned int r_type,
3212     const Sized_symbol<size>* gsym,
3213     const Symbol_value<size>* psymval,
3214     unsigned char* view,
3215     typename elfcpp::Elf_types<size>::Elf_Addr address,
3216     section_size_type view_size)
3217 {
3218   if (this->skip_call_tls_get_addr_)
3219     {
3220       if ((r_type != elfcpp::R_X86_64_PLT32
3221            && r_type != elfcpp::R_X86_64_PC32)
3222           || gsym == NULL
3223           || strcmp(gsym->name(), "__tls_get_addr") != 0)
3224         {
3225           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3226                                  _("missing expected TLS relocation"));
3227         }
3228       else
3229         {
3230           this->skip_call_tls_get_addr_ = false;
3231           return false;
3232         }
3233     }
3234
3235   if (view == NULL)
3236     return true;
3237
3238   const Sized_relobj_file<size, false>* object = relinfo->object;
3239
3240   // Pick the value to use for symbols defined in the PLT.
3241   Symbol_value<size> symval;
3242   if (gsym != NULL
3243       && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
3244     {
3245       symval.set_output_value(target->plt_address_for_global(gsym));
3246       psymval = &symval;
3247     }
3248   else if (gsym == NULL && psymval->is_ifunc_symbol())
3249     {
3250       unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3251       if (object->local_has_plt_offset(r_sym))
3252         {
3253           symval.set_output_value(target->plt_address_for_local(object, r_sym));
3254           psymval = &symval;
3255         }
3256     }
3257
3258   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3259
3260   // Get the GOT offset if needed.
3261   // The GOT pointer points to the end of the GOT section.
3262   // We need to subtract the size of the GOT section to get
3263   // the actual offset to use in the relocation.
3264   bool have_got_offset = false;
3265   unsigned int got_offset = 0;
3266   switch (r_type)
3267     {
3268     case elfcpp::R_X86_64_GOT32:
3269     case elfcpp::R_X86_64_GOT64:
3270     case elfcpp::R_X86_64_GOTPLT64:
3271     case elfcpp::R_X86_64_GOTPCREL:
3272     case elfcpp::R_X86_64_GOTPCREL64:
3273       if (gsym != NULL)
3274         {
3275           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
3276           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
3277         }
3278       else
3279         {
3280           unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3281           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
3282           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
3283                         - target->got_size());
3284         }
3285       have_got_offset = true;
3286       break;
3287
3288     default:
3289       break;
3290     }
3291
3292   switch (r_type)
3293     {
3294     case elfcpp::R_X86_64_NONE:
3295     case elfcpp::R_X86_64_GNU_VTINHERIT:
3296     case elfcpp::R_X86_64_GNU_VTENTRY:
3297       break;
3298
3299     case elfcpp::R_X86_64_64:
3300       Relocate_functions<size, false>::rela64(view, object, psymval, addend);
3301       break;
3302
3303     case elfcpp::R_X86_64_PC64:
3304       Relocate_functions<size, false>::pcrela64(view, object, psymval, addend,
3305                                               address);
3306       break;
3307
3308     case elfcpp::R_X86_64_32:
3309       // FIXME: we need to verify that value + addend fits into 32 bits:
3310       //    uint64_t x = value + addend;
3311       //    x == static_cast<uint64_t>(static_cast<uint32_t>(x))
3312       // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
3313       Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3314       break;
3315
3316     case elfcpp::R_X86_64_32S:
3317       // FIXME: we need to verify that value + addend fits into 32 bits:
3318       //    int64_t x = value + addend;   // note this quantity is signed!
3319       //    x == static_cast<int64_t>(static_cast<int32_t>(x))
3320       Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3321       break;
3322
3323     case elfcpp::R_X86_64_PC32:
3324       Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3325                                                 address);
3326       break;
3327
3328     case elfcpp::R_X86_64_16:
3329       Relocate_functions<size, false>::rela16(view, object, psymval, addend);
3330       break;
3331
3332     case elfcpp::R_X86_64_PC16:
3333       Relocate_functions<size, false>::pcrela16(view, object, psymval, addend,
3334                                                 address);
3335       break;
3336
3337     case elfcpp::R_X86_64_8:
3338       Relocate_functions<size, false>::rela8(view, object, psymval, addend);
3339       break;
3340
3341     case elfcpp::R_X86_64_PC8:
3342       Relocate_functions<size, false>::pcrela8(view, object, psymval, addend,
3343                                                address);
3344       break;
3345
3346     case elfcpp::R_X86_64_PLT32:
3347       gold_assert(gsym == NULL
3348                   || gsym->has_plt_offset()
3349                   || gsym->final_value_is_known()
3350                   || (gsym->is_defined()
3351                       && !gsym->is_from_dynobj()
3352                       && !gsym->is_preemptible()));
3353       // Note: while this code looks the same as for R_X86_64_PC32, it
3354       // behaves differently because psymval was set to point to
3355       // the PLT entry, rather than the symbol, in Scan::global().
3356       Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3357                                                 address);
3358       break;
3359
3360     case elfcpp::R_X86_64_PLTOFF64:
3361       {
3362         gold_assert(gsym);
3363         gold_assert(gsym->has_plt_offset()
3364                     || gsym->final_value_is_known());
3365         typename elfcpp::Elf_types<size>::Elf_Addr got_address;
3366         got_address = target->got_section(NULL, NULL)->address();
3367         Relocate_functions<size, false>::rela64(view, object, psymval,
3368                                                 addend - got_address);
3369       }
3370
3371     case elfcpp::R_X86_64_GOT32:
3372       gold_assert(have_got_offset);
3373       Relocate_functions<size, false>::rela32(view, got_offset, addend);
3374       break;
3375
3376     case elfcpp::R_X86_64_GOTPC32:
3377       {
3378         gold_assert(gsym);
3379         typename elfcpp::Elf_types<size>::Elf_Addr value;
3380         value = target->got_plt_section()->address();
3381         Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3382       }
3383       break;
3384
3385     case elfcpp::R_X86_64_GOT64:
3386       // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
3387       // Since we always add a PLT entry, this is equivalent.
3388     case elfcpp::R_X86_64_GOTPLT64:
3389       gold_assert(have_got_offset);
3390       Relocate_functions<size, false>::rela64(view, got_offset, addend);
3391       break;
3392
3393     case elfcpp::R_X86_64_GOTPC64:
3394       {
3395         gold_assert(gsym);
3396         typename elfcpp::Elf_types<size>::Elf_Addr value;
3397         value = target->got_plt_section()->address();
3398         Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3399       }
3400       break;
3401
3402     case elfcpp::R_X86_64_GOTOFF64:
3403       {
3404         typename elfcpp::Elf_types<size>::Elf_Addr value;
3405         value = (psymval->value(object, 0)
3406                  - target->got_plt_section()->address());
3407         Relocate_functions<size, false>::rela64(view, value, addend);
3408       }
3409       break;
3410
3411     case elfcpp::R_X86_64_GOTPCREL:
3412       {
3413         gold_assert(have_got_offset);
3414         typename elfcpp::Elf_types<size>::Elf_Addr value;
3415         value = target->got_plt_section()->address() + got_offset;
3416         Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3417       }
3418       break;
3419
3420     case elfcpp::R_X86_64_GOTPCREL64:
3421       {
3422         gold_assert(have_got_offset);
3423         typename elfcpp::Elf_types<size>::Elf_Addr value;
3424         value = target->got_plt_section()->address() + got_offset;
3425         Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3426       }
3427       break;
3428
3429     case elfcpp::R_X86_64_COPY:
3430     case elfcpp::R_X86_64_GLOB_DAT:
3431     case elfcpp::R_X86_64_JUMP_SLOT:
3432     case elfcpp::R_X86_64_RELATIVE:
3433     case elfcpp::R_X86_64_IRELATIVE:
3434       // These are outstanding tls relocs, which are unexpected when linking
3435     case elfcpp::R_X86_64_TPOFF64:
3436     case elfcpp::R_X86_64_DTPMOD64:
3437     case elfcpp::R_X86_64_TLSDESC:
3438       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3439                              _("unexpected reloc %u in object file"),
3440                              r_type);
3441       break;
3442
3443       // These are initial tls relocs, which are expected when linking
3444     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3445     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3446     case elfcpp::R_X86_64_TLSDESC_CALL:
3447     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3448     case elfcpp::R_X86_64_DTPOFF32:
3449     case elfcpp::R_X86_64_DTPOFF64:
3450     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3451     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3452       this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
3453                          view, address, view_size);
3454       break;
3455
3456     case elfcpp::R_X86_64_SIZE32:
3457     case elfcpp::R_X86_64_SIZE64:
3458     default:
3459       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3460                              _("unsupported reloc %u"),
3461                              r_type);
3462       break;
3463     }
3464
3465   return true;
3466 }
3467
3468 // Perform a TLS relocation.
3469
3470 template<int size>
3471 inline void
3472 Target_x86_64<size>::Relocate::relocate_tls(
3473     const Relocate_info<size, false>* relinfo,
3474     Target_x86_64<size>* target,
3475     size_t relnum,
3476     const elfcpp::Rela<size, false>& rela,
3477     unsigned int r_type,
3478     const Sized_symbol<size>* gsym,
3479     const Symbol_value<size>* psymval,
3480     unsigned char* view,
3481     typename elfcpp::Elf_types<size>::Elf_Addr address,
3482     section_size_type view_size)
3483 {
3484   Output_segment* tls_segment = relinfo->layout->tls_segment();
3485
3486   const Sized_relobj_file<size, false>* object = relinfo->object;
3487   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3488   elfcpp::Shdr<size, false> data_shdr(relinfo->data_shdr);
3489   bool is_executable = (data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0;
3490
3491   typename elfcpp::Elf_types<size>::Elf_Addr value = psymval->value(relinfo->object, 0);
3492
3493   const bool is_final = (gsym == NULL
3494                          ? !parameters->options().shared()
3495                          : gsym->final_value_is_known());
3496   tls::Tls_optimization optimized_type
3497       = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
3498   switch (r_type)
3499     {
3500     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3501       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3502         {
3503           // If this code sequence is used in a non-executable section,
3504           // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3505           // on the assumption that it's being used by itself in a debug
3506           // section.  Therefore, in the unlikely event that the code
3507           // sequence appears in a non-executable section, we simply
3508           // leave it unoptimized.
3509           optimized_type = tls::TLSOPT_NONE;
3510         }
3511       if (optimized_type == tls::TLSOPT_TO_LE)
3512         {
3513           if (tls_segment == NULL)
3514             {
3515               gold_assert(parameters->errors()->error_count() > 0
3516                           || issue_undefined_symbol_error(gsym));
3517               return;
3518             }
3519           this->tls_gd_to_le(relinfo, relnum, tls_segment,
3520                              rela, r_type, value, view,
3521                              view_size);
3522           break;
3523         }
3524       else
3525         {
3526           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3527                                    ? GOT_TYPE_TLS_OFFSET
3528                                    : GOT_TYPE_TLS_PAIR);
3529           unsigned int got_offset;
3530           if (gsym != NULL)
3531             {
3532               gold_assert(gsym->has_got_offset(got_type));
3533               got_offset = gsym->got_offset(got_type) - target->got_size();
3534             }
3535           else
3536             {
3537               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3538               gold_assert(object->local_has_got_offset(r_sym, got_type));
3539               got_offset = (object->local_got_offset(r_sym, got_type)
3540                             - target->got_size());
3541             }
3542           if (optimized_type == tls::TLSOPT_TO_IE)
3543             {
3544               value = target->got_plt_section()->address() + got_offset;
3545               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rela, r_type,
3546                                  value, view, address, view_size);
3547               break;
3548             }
3549           else if (optimized_type == tls::TLSOPT_NONE)
3550             {
3551               // Relocate the field with the offset of the pair of GOT
3552               // entries.
3553               value = target->got_plt_section()->address() + got_offset;
3554               Relocate_functions<size, false>::pcrela32(view, value, addend,
3555                                                         address);
3556               break;
3557             }
3558         }
3559       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3560                              _("unsupported reloc %u"), r_type);
3561       break;
3562
3563     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3564     case elfcpp::R_X86_64_TLSDESC_CALL:
3565       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3566         {
3567           // See above comment for R_X86_64_TLSGD.
3568           optimized_type = tls::TLSOPT_NONE;
3569         }
3570       if (optimized_type == tls::TLSOPT_TO_LE)
3571         {
3572           if (tls_segment == NULL)
3573             {
3574               gold_assert(parameters->errors()->error_count() > 0
3575                           || issue_undefined_symbol_error(gsym));
3576               return;
3577             }
3578           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3579                                   rela, r_type, value, view,
3580                                   view_size);
3581           break;
3582         }
3583       else
3584         {
3585           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3586                                    ? GOT_TYPE_TLS_OFFSET
3587                                    : GOT_TYPE_TLS_DESC);
3588           unsigned int got_offset = 0;
3589           if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC
3590               && optimized_type == tls::TLSOPT_NONE)
3591             {
3592               // We created GOT entries in the .got.tlsdesc portion of
3593               // the .got.plt section, but the offset stored in the
3594               // symbol is the offset within .got.tlsdesc.
3595               got_offset = (target->got_size()
3596                             + target->got_plt_section()->data_size());
3597             }
3598           if (gsym != NULL)
3599             {
3600               gold_assert(gsym->has_got_offset(got_type));
3601               got_offset += gsym->got_offset(got_type) - target->got_size();
3602             }
3603           else
3604             {
3605               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3606               gold_assert(object->local_has_got_offset(r_sym, got_type));
3607               got_offset += (object->local_got_offset(r_sym, got_type)
3608                              - target->got_size());
3609             }
3610           if (optimized_type == tls::TLSOPT_TO_IE)
3611             {
3612               if (tls_segment == NULL)
3613                 {
3614                   gold_assert(parameters->errors()->error_count() > 0
3615                               || issue_undefined_symbol_error(gsym));
3616                   return;
3617                 }
3618               value = target->got_plt_section()->address() + got_offset;
3619               this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment,
3620                                       rela, r_type, value, view, address,
3621                                       view_size);
3622               break;
3623             }
3624           else if (optimized_type == tls::TLSOPT_NONE)
3625             {
3626               if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3627                 {
3628                   // Relocate the field with the offset of the pair of GOT
3629                   // entries.
3630                   value = target->got_plt_section()->address() + got_offset;
3631                   Relocate_functions<size, false>::pcrela32(view, value, addend,
3632                                                             address);
3633                 }
3634               break;
3635             }
3636         }
3637       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3638                              _("unsupported reloc %u"), r_type);
3639       break;
3640
3641     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3642       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3643         {
3644           // See above comment for R_X86_64_TLSGD.
3645           optimized_type = tls::TLSOPT_NONE;
3646         }
3647       if (optimized_type == tls::TLSOPT_TO_LE)
3648         {
3649           if (tls_segment == NULL)
3650             {
3651               gold_assert(parameters->errors()->error_count() > 0
3652                           || issue_undefined_symbol_error(gsym));
3653               return;
3654             }
3655           this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
3656                              value, view, view_size);
3657           break;
3658         }
3659       else if (optimized_type == tls::TLSOPT_NONE)
3660         {
3661           // Relocate the field with the offset of the GOT entry for
3662           // the module index.
3663           unsigned int got_offset;
3664           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3665                         - target->got_size());
3666           value = target->got_plt_section()->address() + got_offset;
3667           Relocate_functions<size, false>::pcrela32(view, value, addend,
3668                                                     address);
3669           break;
3670         }
3671       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3672                              _("unsupported reloc %u"), r_type);
3673       break;
3674
3675     case elfcpp::R_X86_64_DTPOFF32:
3676       // This relocation type is used in debugging information.
3677       // In that case we need to not optimize the value.  If the
3678       // section is not executable, then we assume we should not
3679       // optimize this reloc.  See comments above for R_X86_64_TLSGD,
3680       // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
3681       // R_X86_64_TLSLD.
3682       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3683         {
3684           if (tls_segment == NULL)
3685             {
3686               gold_assert(parameters->errors()->error_count() > 0
3687                           || issue_undefined_symbol_error(gsym));
3688               return;
3689             }
3690           value -= tls_segment->memsz();
3691         }
3692       Relocate_functions<size, false>::rela32(view, value, addend);
3693       break;
3694
3695     case elfcpp::R_X86_64_DTPOFF64:
3696       // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
3697       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3698         {
3699           if (tls_segment == NULL)
3700             {
3701               gold_assert(parameters->errors()->error_count() > 0
3702                           || issue_undefined_symbol_error(gsym));
3703               return;
3704             }
3705           value -= tls_segment->memsz();
3706         }
3707       Relocate_functions<size, false>::rela64(view, value, addend);
3708       break;
3709
3710     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3711       if (optimized_type == tls::TLSOPT_TO_LE)
3712         {
3713           if (tls_segment == NULL)
3714             {
3715               gold_assert(parameters->errors()->error_count() > 0
3716                           || issue_undefined_symbol_error(gsym));
3717               return;
3718             }
3719           Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
3720                                                       tls_segment, rela,
3721                                                       r_type, value, view,
3722                                                       view_size);
3723           break;
3724         }
3725       else if (optimized_type == tls::TLSOPT_NONE)
3726         {
3727           // Relocate the field with the offset of the GOT entry for
3728           // the tp-relative offset of the symbol.
3729           unsigned int got_offset;
3730           if (gsym != NULL)
3731             {
3732               gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
3733               got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
3734                             - target->got_size());
3735             }
3736           else
3737             {
3738               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3739               gold_assert(object->local_has_got_offset(r_sym,
3740                                                        GOT_TYPE_TLS_OFFSET));
3741               got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
3742                             - target->got_size());
3743             }
3744           value = target->got_plt_section()->address() + got_offset;
3745           Relocate_functions<size, false>::pcrela32(view, value, addend,
3746                                                     address);
3747           break;
3748         }
3749       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3750                              _("unsupported reloc type %u"),
3751                              r_type);
3752       break;
3753
3754     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3755       if (tls_segment == NULL)
3756         {
3757           gold_assert(parameters->errors()->error_count() > 0
3758                       || issue_undefined_symbol_error(gsym));
3759           return;
3760         }
3761       value -= tls_segment->memsz();
3762       Relocate_functions<size, false>::rela32(view, value, addend);
3763       break;
3764     }
3765 }
3766
3767 // Do a relocation in which we convert a TLS General-Dynamic to an
3768 // Initial-Exec.
3769
3770 template<int size>
3771 inline void
3772 Target_x86_64<size>::Relocate::tls_gd_to_ie(
3773     const Relocate_info<size, false>* relinfo,
3774     size_t relnum,
3775     Output_segment*,
3776     const elfcpp::Rela<size, false>& rela,
3777     unsigned int,
3778     typename elfcpp::Elf_types<size>::Elf_Addr value,
3779     unsigned char* view,
3780     typename elfcpp::Elf_types<size>::Elf_Addr address,
3781     section_size_type view_size)
3782 {
3783   // For SIZE == 64:
3784   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3785   //    .word 0x6666; rex64; call __tls_get_addr
3786   //    ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
3787   // For SIZE == 32:
3788   //    leaq foo@tlsgd(%rip),%rdi;
3789   //    .word 0x6666; rex64; call __tls_get_addr
3790   //    ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
3791
3792   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3793   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3794                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3795
3796   if (size == 64)
3797     {
3798       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3799                        -4);
3800       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3801                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3802       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3803              16);
3804     }
3805   else
3806     {
3807       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3808                        -3);
3809       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3810                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3811       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3812              15);
3813     }
3814
3815   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3816   Relocate_functions<size, false>::pcrela32(view + 8, value, addend - 8,
3817                                             address);
3818
3819   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3820   // We can skip it.
3821   this->skip_call_tls_get_addr_ = true;
3822 }
3823
3824 // Do a relocation in which we convert a TLS General-Dynamic to a
3825 // Local-Exec.
3826
3827 template<int size>
3828 inline void
3829 Target_x86_64<size>::Relocate::tls_gd_to_le(
3830     const Relocate_info<size, false>* relinfo,
3831     size_t relnum,
3832     Output_segment* tls_segment,
3833     const elfcpp::Rela<size, false>& rela,
3834     unsigned int,
3835     typename elfcpp::Elf_types<size>::Elf_Addr value,
3836     unsigned char* view,
3837     section_size_type view_size)
3838 {
3839   // For SIZE == 64:
3840   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3841   //    .word 0x6666; rex64; call __tls_get_addr
3842   //    ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
3843   // For SIZE == 32:
3844   //    leaq foo@tlsgd(%rip),%rdi;
3845   //    .word 0x6666; rex64; call __tls_get_addr
3846   //    ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
3847
3848   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3849   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3850                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3851
3852   if (size == 64)
3853     {
3854       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3855                        -4);
3856       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3857                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3858       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3859              16);
3860     }
3861   else
3862     {
3863       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3864                        -3);
3865       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3866                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3867
3868       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3869              15);
3870     }
3871
3872   value -= tls_segment->memsz();
3873   Relocate_functions<size, false>::rela32(view + 8, value, 0);
3874
3875   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3876   // We can skip it.
3877   this->skip_call_tls_get_addr_ = true;
3878 }
3879
3880 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
3881
3882 template<int size>
3883 inline void
3884 Target_x86_64<size>::Relocate::tls_desc_gd_to_ie(
3885     const Relocate_info<size, false>* relinfo,
3886     size_t relnum,
3887     Output_segment*,
3888     const elfcpp::Rela<size, false>& rela,
3889     unsigned int r_type,
3890     typename elfcpp::Elf_types<size>::Elf_Addr value,
3891     unsigned char* view,
3892     typename elfcpp::Elf_types<size>::Elf_Addr address,
3893     section_size_type view_size)
3894 {
3895   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3896     {
3897       // leaq foo@tlsdesc(%rip), %rax
3898       // ==> movq foo@gottpoff(%rip), %rax
3899       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3900       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3901       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3902                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3903       view[-2] = 0x8b;
3904       const elfcpp::Elf_Xword addend = rela.get_r_addend();
3905       Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3906     }
3907   else
3908     {
3909       // call *foo@tlscall(%rax)
3910       // ==> nop; nop
3911       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3912       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3913       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3914                      view[0] == 0xff && view[1] == 0x10);
3915       view[0] = 0x66;
3916       view[1] = 0x90;
3917     }
3918 }
3919
3920 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
3921
3922 template<int size>
3923 inline void
3924 Target_x86_64<size>::Relocate::tls_desc_gd_to_le(
3925     const Relocate_info<size, false>* relinfo,
3926     size_t relnum,
3927     Output_segment* tls_segment,
3928     const elfcpp::Rela<size, false>& rela,
3929     unsigned int r_type,
3930     typename elfcpp::Elf_types<size>::Elf_Addr value,
3931     unsigned char* view,
3932     section_size_type view_size)
3933 {
3934   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3935     {
3936       // leaq foo@tlsdesc(%rip), %rax
3937       // ==> movq foo@tpoff, %rax
3938       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3939       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3940       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3941                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3942       view[-2] = 0xc7;
3943       view[-1] = 0xc0;
3944       value -= tls_segment->memsz();
3945       Relocate_functions<size, false>::rela32(view, value, 0);
3946     }
3947   else
3948     {
3949       // call *foo@tlscall(%rax)
3950       // ==> nop; nop
3951       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3952       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3953       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3954                      view[0] == 0xff && view[1] == 0x10);
3955       view[0] = 0x66;
3956       view[1] = 0x90;
3957     }
3958 }
3959
3960 template<int size>
3961 inline void
3962 Target_x86_64<size>::Relocate::tls_ld_to_le(
3963     const Relocate_info<size, false>* relinfo,
3964     size_t relnum,
3965     Output_segment*,
3966     const elfcpp::Rela<size, false>& rela,
3967     unsigned int,
3968     typename elfcpp::Elf_types<size>::Elf_Addr,
3969     unsigned char* view,
3970     section_size_type view_size)
3971 {
3972   // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
3973   // For SIZE == 64:
3974   // ... leq foo@dtpoff(%rax),%reg
3975   // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
3976   // For SIZE == 32:
3977   // ... leq foo@dtpoff(%rax),%reg
3978   // ==> nopl 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
3979
3980   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3981   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 9);
3982
3983   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3984                  view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
3985
3986   tls::check_tls(relinfo, relnum, rela.get_r_offset(), view[4] == 0xe8);
3987
3988   if (size == 64)
3989     memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
3990   else
3991     memcpy(view - 3, "\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0", 12);
3992
3993   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3994   // We can skip it.
3995   this->skip_call_tls_get_addr_ = true;
3996 }
3997
3998 // Do a relocation in which we convert a TLS Initial-Exec to a
3999 // Local-Exec.
4000
4001 template<int size>
4002 inline void
4003 Target_x86_64<size>::Relocate::tls_ie_to_le(
4004     const Relocate_info<size, false>* relinfo,
4005     size_t relnum,
4006     Output_segment* tls_segment,
4007     const elfcpp::Rela<size, false>& rela,
4008     unsigned int,
4009     typename elfcpp::Elf_types<size>::Elf_Addr value,
4010     unsigned char* view,
4011     section_size_type view_size)
4012 {
4013   // We need to examine the opcodes to figure out which instruction we
4014   // are looking at.
4015
4016   // movq foo@gottpoff(%rip),%reg  ==>  movq $YY,%reg
4017   // addq foo@gottpoff(%rip),%reg  ==>  addq $YY,%reg
4018
4019   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4020   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
4021
4022   unsigned char op1 = view[-3];
4023   unsigned char op2 = view[-2];
4024   unsigned char op3 = view[-1];
4025   unsigned char reg = op3 >> 3;
4026
4027   if (op2 == 0x8b)
4028     {
4029       // movq
4030       if (op1 == 0x4c)
4031         view[-3] = 0x49;
4032       view[-2] = 0xc7;
4033       view[-1] = 0xc0 | reg;
4034     }
4035   else if (reg == 4)
4036     {
4037       // Special handling for %rsp.
4038       if (op1 == 0x4c)
4039         view[-3] = 0x49;
4040       view[-2] = 0x81;
4041       view[-1] = 0xc0 | reg;
4042     }
4043   else
4044     {
4045       // addq
4046       if (op1 == 0x4c)
4047         view[-3] = 0x4d;
4048       view[-2] = 0x8d;
4049       view[-1] = 0x80 | reg | (reg << 3);
4050     }
4051
4052   value -= tls_segment->memsz();
4053   Relocate_functions<size, false>::rela32(view, value, 0);
4054 }
4055
4056 // Relocate section data.
4057
4058 template<int size>
4059 void
4060 Target_x86_64<size>::relocate_section(
4061     const Relocate_info<size, false>* relinfo,
4062     unsigned int sh_type,
4063     const unsigned char* prelocs,
4064     size_t reloc_count,
4065     Output_section* output_section,
4066     bool needs_special_offset_handling,
4067     unsigned char* view,
4068     typename elfcpp::Elf_types<size>::Elf_Addr address,
4069     section_size_type view_size,
4070     const Reloc_symbol_changes* reloc_symbol_changes)
4071 {
4072   gold_assert(sh_type == elfcpp::SHT_RELA);
4073
4074   gold::relocate_section<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
4075                          typename Target_x86_64<size>::Relocate,
4076                          gold::Default_comdat_behavior>(
4077     relinfo,
4078     this,
4079     prelocs,
4080     reloc_count,
4081     output_section,
4082     needs_special_offset_handling,
4083     view,
4084     address,
4085     view_size,
4086     reloc_symbol_changes);
4087 }
4088
4089 // Apply an incremental relocation.  Incremental relocations always refer
4090 // to global symbols.
4091
4092 template<int size>
4093 void
4094 Target_x86_64<size>::apply_relocation(
4095     const Relocate_info<size, false>* relinfo,
4096     typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
4097     unsigned int r_type,
4098     typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
4099     const Symbol* gsym,
4100     unsigned char* view,
4101     typename elfcpp::Elf_types<size>::Elf_Addr address,
4102     section_size_type view_size)
4103 {
4104   gold::apply_relocation<size, false, Target_x86_64<size>,
4105                          typename Target_x86_64<size>::Relocate>(
4106     relinfo,
4107     this,
4108     r_offset,
4109     r_type,
4110     r_addend,
4111     gsym,
4112     view,
4113     address,
4114     view_size);
4115 }
4116
4117 // Return the size of a relocation while scanning during a relocatable
4118 // link.
4119
4120 template<int size>
4121 unsigned int
4122 Target_x86_64<size>::Relocatable_size_for_reloc::get_size_for_reloc(
4123     unsigned int r_type,
4124     Relobj* object)
4125 {
4126   switch (r_type)
4127     {
4128     case elfcpp::R_X86_64_NONE:
4129     case elfcpp::R_X86_64_GNU_VTINHERIT:
4130     case elfcpp::R_X86_64_GNU_VTENTRY:
4131     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
4132     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
4133     case elfcpp::R_X86_64_TLSDESC_CALL:
4134     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
4135     case elfcpp::R_X86_64_DTPOFF32:
4136     case elfcpp::R_X86_64_DTPOFF64:
4137     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
4138     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
4139       return 0;
4140
4141     case elfcpp::R_X86_64_64:
4142     case elfcpp::R_X86_64_PC64:
4143     case elfcpp::R_X86_64_GOTOFF64:
4144     case elfcpp::R_X86_64_GOTPC64:
4145     case elfcpp::R_X86_64_PLTOFF64:
4146     case elfcpp::R_X86_64_GOT64:
4147     case elfcpp::R_X86_64_GOTPCREL64:
4148     case elfcpp::R_X86_64_GOTPCREL:
4149     case elfcpp::R_X86_64_GOTPLT64:
4150       return 8;
4151
4152     case elfcpp::R_X86_64_32:
4153     case elfcpp::R_X86_64_32S:
4154     case elfcpp::R_X86_64_PC32:
4155     case elfcpp::R_X86_64_PLT32:
4156     case elfcpp::R_X86_64_GOTPC32:
4157     case elfcpp::R_X86_64_GOT32:
4158       return 4;
4159
4160     case elfcpp::R_X86_64_16:
4161     case elfcpp::R_X86_64_PC16:
4162       return 2;
4163
4164     case elfcpp::R_X86_64_8:
4165     case elfcpp::R_X86_64_PC8:
4166       return 1;
4167
4168     case elfcpp::R_X86_64_COPY:
4169     case elfcpp::R_X86_64_GLOB_DAT:
4170     case elfcpp::R_X86_64_JUMP_SLOT:
4171     case elfcpp::R_X86_64_RELATIVE:
4172     case elfcpp::R_X86_64_IRELATIVE:
4173       // These are outstanding tls relocs, which are unexpected when linking
4174     case elfcpp::R_X86_64_TPOFF64:
4175     case elfcpp::R_X86_64_DTPMOD64:
4176     case elfcpp::R_X86_64_TLSDESC:
4177       object->error(_("unexpected reloc %u in object file"), r_type);
4178       return 0;
4179
4180     case elfcpp::R_X86_64_SIZE32:
4181     case elfcpp::R_X86_64_SIZE64:
4182     default:
4183       object->error(_("unsupported reloc %u against local symbol"), r_type);
4184       return 0;
4185     }
4186 }
4187
4188 // Scan the relocs during a relocatable link.
4189
4190 template<int size>
4191 void
4192 Target_x86_64<size>::scan_relocatable_relocs(
4193     Symbol_table* symtab,
4194     Layout* layout,
4195     Sized_relobj_file<size, false>* object,
4196     unsigned int data_shndx,
4197     unsigned int sh_type,
4198     const unsigned char* prelocs,
4199     size_t reloc_count,
4200     Output_section* output_section,
4201     bool needs_special_offset_handling,
4202     size_t local_symbol_count,
4203     const unsigned char* plocal_symbols,
4204     Relocatable_relocs* rr)
4205 {
4206   gold_assert(sh_type == elfcpp::SHT_RELA);
4207
4208   typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
4209     Relocatable_size_for_reloc> Scan_relocatable_relocs;
4210
4211   gold::scan_relocatable_relocs<size, false, elfcpp::SHT_RELA,
4212       Scan_relocatable_relocs>(
4213     symtab,
4214     layout,
4215     object,
4216     data_shndx,
4217     prelocs,
4218     reloc_count,
4219     output_section,
4220     needs_special_offset_handling,
4221     local_symbol_count,
4222     plocal_symbols,
4223     rr);
4224 }
4225
4226 // Relocate a section during a relocatable link.
4227
4228 template<int size>
4229 void
4230 Target_x86_64<size>::relocate_relocs(
4231     const Relocate_info<size, false>* relinfo,
4232     unsigned int sh_type,
4233     const unsigned char* prelocs,
4234     size_t reloc_count,
4235     Output_section* output_section,
4236     typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
4237     const Relocatable_relocs* rr,
4238     unsigned char* view,
4239     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
4240     section_size_type view_size,
4241     unsigned char* reloc_view,
4242     section_size_type reloc_view_size)
4243 {
4244   gold_assert(sh_type == elfcpp::SHT_RELA);
4245
4246   gold::relocate_relocs<size, false, elfcpp::SHT_RELA>(
4247     relinfo,
4248     prelocs,
4249     reloc_count,
4250     output_section,
4251     offset_in_output_section,
4252     rr,
4253     view,
4254     view_address,
4255     view_size,
4256     reloc_view,
4257     reloc_view_size);
4258 }
4259
4260 // Return the value to use for a dynamic which requires special
4261 // treatment.  This is how we support equality comparisons of function
4262 // pointers across shared library boundaries, as described in the
4263 // processor specific ABI supplement.
4264
4265 template<int size>
4266 uint64_t
4267 Target_x86_64<size>::do_dynsym_value(const Symbol* gsym) const
4268 {
4269   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
4270   return this->plt_address_for_global(gsym);
4271 }
4272
4273 // Return a string used to fill a code section with nops to take up
4274 // the specified length.
4275
4276 template<int size>
4277 std::string
4278 Target_x86_64<size>::do_code_fill(section_size_type length) const
4279 {
4280   if (length >= 16)
4281     {
4282       // Build a jmpq instruction to skip over the bytes.
4283       unsigned char jmp[5];
4284       jmp[0] = 0xe9;
4285       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
4286       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
4287               + std::string(length - 5, static_cast<char>(0x90)));
4288     }
4289
4290   // Nop sequences of various lengths.
4291   const char nop1[1] = { '\x90' };                 // nop
4292   const char nop2[2] = { '\x66', '\x90' };         // xchg %ax %ax
4293   const char nop3[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
4294   const char nop4[4] = { '\x0f', '\x1f', '\x40',   // nop 0(%rax)
4295                          '\x00'};
4296   const char nop5[5] = { '\x0f', '\x1f', '\x44',   // nop 0(%rax,%rax,1)
4297                          '\x00', '\x00' };
4298   const char nop6[6] = { '\x66', '\x0f', '\x1f',   // nopw 0(%rax,%rax,1)
4299                          '\x44', '\x00', '\x00' };
4300   const char nop7[7] = { '\x0f', '\x1f', '\x80',   // nopl 0L(%rax)
4301                          '\x00', '\x00', '\x00',
4302                          '\x00' };
4303   const char nop8[8] = { '\x0f', '\x1f', '\x84',   // nopl 0L(%rax,%rax,1)
4304                          '\x00', '\x00', '\x00',
4305                          '\x00', '\x00' };
4306   const char nop9[9] = { '\x66', '\x0f', '\x1f',   // nopw 0L(%rax,%rax,1)
4307                          '\x84', '\x00', '\x00',
4308                          '\x00', '\x00', '\x00' };
4309   const char nop10[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4310                            '\x1f', '\x84', '\x00',
4311                            '\x00', '\x00', '\x00',
4312                            '\x00' };
4313   const char nop11[11] = { '\x66', '\x66', '\x2e', // data16
4314                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4315                            '\x00', '\x00', '\x00',
4316                            '\x00', '\x00' };
4317   const char nop12[12] = { '\x66', '\x66', '\x66', // data16; data16
4318                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4319                            '\x84', '\x00', '\x00',
4320                            '\x00', '\x00', '\x00' };
4321   const char nop13[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4322                            '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4323                            '\x1f', '\x84', '\x00',
4324                            '\x00', '\x00', '\x00',
4325                            '\x00' };
4326   const char nop14[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4327                            '\x66', '\x66', '\x2e', // data16
4328                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4329                            '\x00', '\x00', '\x00',
4330                            '\x00', '\x00' };
4331   const char nop15[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4332                            '\x66', '\x66', '\x66', // data16; data16
4333                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4334                            '\x84', '\x00', '\x00',
4335                            '\x00', '\x00', '\x00' };
4336
4337   const char* nops[16] = {
4338     NULL,
4339     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
4340     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
4341   };
4342
4343   return std::string(nops[length], length);
4344 }
4345
4346 // Return the addend to use for a target specific relocation.  The
4347 // only target specific relocation is R_X86_64_TLSDESC for a local
4348 // symbol.  We want to set the addend is the offset of the local
4349 // symbol in the TLS segment.
4350
4351 template<int size>
4352 uint64_t
4353 Target_x86_64<size>::do_reloc_addend(void* arg, unsigned int r_type,
4354                                      uint64_t) const
4355 {
4356   gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
4357   uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
4358   gold_assert(intarg < this->tlsdesc_reloc_info_.size());
4359   const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
4360   const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
4361   gold_assert(psymval->is_tls_symbol());
4362   // The value of a TLS symbol is the offset in the TLS segment.
4363   return psymval->value(ti.object, 0);
4364 }
4365
4366 // Return the value to use for the base of a DW_EH_PE_datarel offset
4367 // in an FDE.  Solaris and SVR4 use DW_EH_PE_datarel because their
4368 // assembler can not write out the difference between two labels in
4369 // different sections, so instead of using a pc-relative value they
4370 // use an offset from the GOT.
4371
4372 template<int size>
4373 uint64_t
4374 Target_x86_64<size>::do_ehframe_datarel_base() const
4375 {
4376   gold_assert(this->global_offset_table_ != NULL);
4377   Symbol* sym = this->global_offset_table_;
4378   Sized_symbol<size>* ssym = static_cast<Sized_symbol<size>*>(sym);
4379   return ssym->value();
4380 }
4381
4382 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4383 // compiled with -fsplit-stack.  The function calls non-split-stack
4384 // code.  We have to change the function so that it always ensures
4385 // that it has enough stack space to run some random function.
4386
4387 template<int size>
4388 void
4389 Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx,
4390                                         section_offset_type fnoffset,
4391                                         section_size_type fnsize,
4392                                         unsigned char* view,
4393                                         section_size_type view_size,
4394                                         std::string* from,
4395                                         std::string* to) const
4396 {
4397   // The function starts with a comparison of the stack pointer and a
4398   // field in the TCB.  This is followed by a jump.
4399
4400   // cmp %fs:NN,%rsp
4401   if (this->match_view(view, view_size, fnoffset, "\x64\x48\x3b\x24\x25", 5)
4402       && fnsize > 9)
4403     {
4404       // We will call __morestack if the carry flag is set after this
4405       // comparison.  We turn the comparison into an stc instruction
4406       // and some nops.
4407       view[fnoffset] = '\xf9';
4408       this->set_view_to_nop(view, view_size, fnoffset + 1, 8);
4409     }
4410   // lea NN(%rsp),%r10
4411   // lea NN(%rsp),%r11
4412   else if ((this->match_view(view, view_size, fnoffset,
4413                              "\x4c\x8d\x94\x24", 4)
4414             || this->match_view(view, view_size, fnoffset,
4415                                 "\x4c\x8d\x9c\x24", 4))
4416            && fnsize > 8)
4417     {
4418       // This is loading an offset from the stack pointer for a
4419       // comparison.  The offset is negative, so we decrease the
4420       // offset by the amount of space we need for the stack.  This
4421       // means we will avoid calling __morestack if there happens to
4422       // be plenty of space on the stack already.
4423       unsigned char* pval = view + fnoffset + 4;
4424       uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
4425       val -= parameters->options().split_stack_adjust_size();
4426       elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
4427     }
4428   else
4429     {
4430       if (!object->has_no_split_stack())
4431         object->error(_("failed to match split-stack sequence at "
4432                         "section %u offset %0zx"),
4433                       shndx, static_cast<size_t>(fnoffset));
4434       return;
4435     }
4436
4437   // We have to change the function so that it calls
4438   // __morestack_non_split instead of __morestack.  The former will
4439   // allocate additional stack space.
4440   *from = "__morestack";
4441   *to = "__morestack_non_split";
4442 }
4443
4444 // The selector for x86_64 object files.  Note this is never instantiated
4445 // directly.  It's only used in Target_selector_x86_64_nacl, below.
4446
4447 template<int size>
4448 class Target_selector_x86_64 : public Target_selector_freebsd
4449 {
4450 public:
4451   Target_selector_x86_64()
4452     : Target_selector_freebsd(elfcpp::EM_X86_64, size, false,
4453                               (size == 64
4454                                ? "elf64-x86-64" : "elf32-x86-64"),
4455                               (size == 64
4456                                ? "elf64-x86-64-freebsd"
4457                                : "elf32-x86-64-freebsd"),
4458                               (size == 64 ? "elf_x86_64" : "elf32_x86_64"))
4459   { }
4460
4461   Target*
4462   do_instantiate_target()
4463   { return new Target_x86_64<size>(); }
4464
4465 };
4466
4467 // NaCl variant.  It uses different PLT contents.
4468
4469 template<int size>
4470 class Output_data_plt_x86_64_nacl : public Output_data_plt_x86_64<size>
4471 {
4472  public:
4473   Output_data_plt_x86_64_nacl(Layout* layout,
4474                               Output_data_got<64, false>* got,
4475                               Output_data_space* got_plt,
4476                               Output_data_space* got_irelative)
4477     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4478                                    got, got_plt, got_irelative)
4479   { }
4480
4481   Output_data_plt_x86_64_nacl(Layout* layout,
4482                               Output_data_got<64, false>* got,
4483                               Output_data_space* got_plt,
4484                               Output_data_space* got_irelative,
4485                               unsigned int plt_count)
4486     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4487                                    got, got_plt, got_irelative,
4488                                    plt_count)
4489   { }
4490
4491  protected:
4492   virtual unsigned int
4493   do_get_plt_entry_size() const
4494   { return plt_entry_size; }
4495
4496   virtual void
4497   do_add_eh_frame(Layout* layout)
4498   {
4499     layout->add_eh_frame_for_plt(this,
4500                                  this->plt_eh_frame_cie,
4501                                  this->plt_eh_frame_cie_size,
4502                                  plt_eh_frame_fde,
4503                                  plt_eh_frame_fde_size);
4504   }
4505
4506   virtual void
4507   do_fill_first_plt_entry(unsigned char* pov,
4508                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
4509                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
4510
4511   virtual unsigned int
4512   do_fill_plt_entry(unsigned char* pov,
4513                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4514                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4515                     unsigned int got_offset,
4516                     unsigned int plt_offset,
4517                     unsigned int plt_index);
4518
4519   virtual void
4520   do_fill_tlsdesc_entry(unsigned char* pov,
4521                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4522                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4523                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4524                         unsigned int tlsdesc_got_offset,
4525                         unsigned int plt_offset);
4526
4527  private:
4528   // The size of an entry in the PLT.
4529   static const int plt_entry_size = 64;
4530
4531   // The first entry in the PLT.
4532   static const unsigned char first_plt_entry[plt_entry_size];
4533
4534   // Other entries in the PLT for an executable.
4535   static const unsigned char plt_entry[plt_entry_size];
4536
4537   // The reserved TLSDESC entry in the PLT for an executable.
4538   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
4539
4540   // The .eh_frame unwind information for the PLT.
4541   static const int plt_eh_frame_fde_size = 32;
4542   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4543 };
4544
4545 template<int size>
4546 class Target_x86_64_nacl : public Target_x86_64<size>
4547 {
4548  public:
4549   Target_x86_64_nacl()
4550     : Target_x86_64<size>(&x86_64_nacl_info)
4551   { }
4552
4553   virtual Output_data_plt_x86_64<size>*
4554   do_make_data_plt(Layout* layout,
4555                    Output_data_got<64, false>* got,
4556                    Output_data_space* got_plt,
4557                    Output_data_space* got_irelative)
4558   {
4559     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4560                                                  got_irelative);
4561   }
4562
4563   virtual Output_data_plt_x86_64<size>*
4564   do_make_data_plt(Layout* layout,
4565                    Output_data_got<64, false>* got,
4566                    Output_data_space* got_plt,
4567                    Output_data_space* got_irelative,
4568                    unsigned int plt_count)
4569   {
4570     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4571                                                  got_irelative,
4572                                                  plt_count);
4573   }
4574
4575   virtual std::string
4576   do_code_fill(section_size_type length) const;
4577
4578  private:
4579   static const Target::Target_info x86_64_nacl_info;
4580 };
4581
4582 template<>
4583 const Target::Target_info Target_x86_64_nacl<64>::x86_64_nacl_info =
4584 {
4585   64,                   // size
4586   false,                // is_big_endian
4587   elfcpp::EM_X86_64,    // machine_code
4588   false,                // has_make_symbol
4589   false,                // has_resolve
4590   true,                 // has_code_fill
4591   true,                 // is_default_stack_executable
4592   true,                 // can_icf_inline_merge_sections
4593   '\0',                 // wrap_char
4594   "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
4595   0x20000,              // default_text_segment_address
4596   0x10000,              // abi_pagesize (overridable by -z max-page-size)
4597   0x10000,              // common_pagesize (overridable by -z common-page-size)
4598   true,                 // isolate_execinstr
4599   0x10000000,           // rosegment_gap
4600   elfcpp::SHN_UNDEF,    // small_common_shndx
4601   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
4602   0,                    // small_common_section_flags
4603   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
4604   NULL,                 // attributes_section
4605   NULL,                 // attributes_vendor
4606   "_start"              // entry_symbol_name
4607 };
4608
4609 template<>
4610 const Target::Target_info Target_x86_64_nacl<32>::x86_64_nacl_info =
4611 {
4612   32,                   // size
4613   false,                // is_big_endian
4614   elfcpp::EM_X86_64,    // machine_code
4615   false,                // has_make_symbol
4616   false,                // has_resolve
4617   true,                 // has_code_fill
4618   true,                 // is_default_stack_executable
4619   true,                 // can_icf_inline_merge_sections
4620   '\0',                 // wrap_char
4621   "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
4622   0x20000,              // default_text_segment_address
4623   0x10000,              // abi_pagesize (overridable by -z max-page-size)
4624   0x10000,              // common_pagesize (overridable by -z common-page-size)
4625   true,                 // isolate_execinstr
4626   0x10000000,           // rosegment_gap
4627   elfcpp::SHN_UNDEF,    // small_common_shndx
4628   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
4629   0,                    // small_common_section_flags
4630   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
4631   NULL,                 // attributes_section
4632   NULL,                 // attributes_vendor
4633   "_start"              // entry_symbol_name
4634 };
4635
4636 #define NACLMASK        0xe0            // 32-byte alignment mask.
4637
4638 // The first entry in the PLT.
4639
4640 template<int size>
4641 const unsigned char
4642 Output_data_plt_x86_64_nacl<size>::first_plt_entry[plt_entry_size] =
4643 {
4644   0xff, 0x35,                         // pushq contents of memory address
4645   0, 0, 0, 0,                         // replaced with address of .got + 8
4646   0x4c, 0x8b, 0x1d,                   // mov GOT+16(%rip), %r11
4647   0, 0, 0, 0,                         // replaced with address of .got + 16
4648   0x41, 0x83, 0xe3, NACLMASK,         // and $-32, %r11d
4649   0x4d, 0x01, 0xfb,                   // add %r15, %r11
4650   0x41, 0xff, 0xe3,                   // jmpq *%r11
4651
4652   // 9-byte nop sequence to pad out to the next 32-byte boundary.
4653   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopl %cs:0x0(%rax,%rax,1)
4654
4655   // 32 bytes of nop to pad out to the standard size
4656   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4657   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4658   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4659   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4660   0x66,                                  // excess data32 prefix
4661   0x90                                   // nop
4662 };
4663
4664 template<int size>
4665 void
4666 Output_data_plt_x86_64_nacl<size>::do_fill_first_plt_entry(
4667     unsigned char* pov,
4668     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4669     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
4670 {
4671   memcpy(pov, first_plt_entry, plt_entry_size);
4672   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4673                                               (got_address + 8
4674                                                - (plt_address + 2 + 4)));
4675   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4676                                               (got_address + 16
4677                                                - (plt_address + 9 + 4)));
4678 }
4679
4680 // Subsequent entries in the PLT.
4681
4682 template<int size>
4683 const unsigned char
4684 Output_data_plt_x86_64_nacl<size>::plt_entry[plt_entry_size] =
4685 {
4686   0x4c, 0x8b, 0x1d,              // mov name@GOTPCREL(%rip),%r11
4687   0, 0, 0, 0,                    // replaced with address of symbol in .got
4688   0x41, 0x83, 0xe3, NACLMASK,    // and $-32, %r11d
4689   0x4d, 0x01, 0xfb,              // add %r15, %r11
4690   0x41, 0xff, 0xe3,              // jmpq *%r11
4691
4692   // 15-byte nop sequence to pad out to the next 32-byte boundary.
4693   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4694   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4695
4696   // Lazy GOT entries point here (32-byte aligned).
4697   0x68,                       // pushq immediate
4698   0, 0, 0, 0,                 // replaced with index into relocation table
4699   0xe9,                       // jmp relative
4700   0, 0, 0, 0,                 // replaced with offset to start of .plt0
4701
4702   // 22 bytes of nop to pad out to the standard size.
4703   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4704   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4705   0x0f, 0x1f, 0x80, 0, 0, 0, 0,          // nopl 0x0(%rax)
4706 };
4707
4708 template<int size>
4709 unsigned int
4710 Output_data_plt_x86_64_nacl<size>::do_fill_plt_entry(
4711     unsigned char* pov,
4712     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4713     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4714     unsigned int got_offset,
4715     unsigned int plt_offset,
4716     unsigned int plt_index)
4717 {
4718   memcpy(pov, plt_entry, plt_entry_size);
4719   elfcpp::Swap_unaligned<32, false>::writeval(pov + 3,
4720                                               (got_address + got_offset
4721                                                - (plt_address + plt_offset
4722                                                   + 3 + 4)));
4723
4724   elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_index);
4725   elfcpp::Swap_unaligned<32, false>::writeval(pov + 38,
4726                                               - (plt_offset + 38 + 4));
4727
4728   return 32;
4729 }
4730
4731 // The reserved TLSDESC entry in the PLT.
4732
4733 template<int size>
4734 const unsigned char
4735 Output_data_plt_x86_64_nacl<size>::tlsdesc_plt_entry[plt_entry_size] =
4736 {
4737   0xff, 0x35,                   // pushq x(%rip)
4738   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
4739   0x4c, 0x8b, 0x1d,             // mov y(%rip),%r11
4740   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
4741   0x41, 0x83, 0xe3, NACLMASK,   // and $-32, %r11d
4742   0x4d, 0x01, 0xfb,             // add %r15, %r11
4743   0x41, 0xff, 0xe3,             // jmpq *%r11
4744
4745   // 41 bytes of nop to pad out to the standard size.
4746   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4747   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4748   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4749   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4750   0x66, 0x66,                            // excess data32 prefixes
4751   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4752 };
4753
4754 template<int size>
4755 void
4756 Output_data_plt_x86_64_nacl<size>::do_fill_tlsdesc_entry(
4757     unsigned char* pov,
4758     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4759     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4760     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4761     unsigned int tlsdesc_got_offset,
4762     unsigned int plt_offset)
4763 {
4764   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
4765   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4766                                               (got_address + 8
4767                                                - (plt_address + plt_offset
4768                                                   + 2 + 4)));
4769   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4770                                               (got_base
4771                                                + tlsdesc_got_offset
4772                                                - (plt_address + plt_offset
4773                                                   + 9 + 4)));
4774 }
4775
4776 // The .eh_frame unwind information for the PLT.
4777
4778 template<int size>
4779 const unsigned char
4780 Output_data_plt_x86_64_nacl<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4781 {
4782   0, 0, 0, 0,                           // Replaced with offset to .plt.
4783   0, 0, 0, 0,                           // Replaced with size of .plt.
4784   0,                                    // Augmentation size.
4785   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
4786   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
4787   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
4788   elfcpp::DW_CFA_advance_loc + 58,      // Advance 58 to __PLT__ + 64.
4789   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
4790   13,                                   // Block length.
4791   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
4792   elfcpp::DW_OP_breg16, 0,              // Push %rip.
4793   elfcpp::DW_OP_const1u, 63,            // Push 0x3f.
4794   elfcpp::DW_OP_and,                    // & (%rip & 0x3f).
4795   elfcpp::DW_OP_const1u, 37,            // Push 0x25.
4796   elfcpp::DW_OP_ge,                     // >= ((%rip & 0x3f) >= 0x25)
4797   elfcpp::DW_OP_lit3,                   // Push 3.
4798   elfcpp::DW_OP_shl,                    // << (((%rip & 0x3f) >= 0x25) << 3)
4799   elfcpp::DW_OP_plus,                   // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
4800   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
4801   elfcpp::DW_CFA_nop
4802 };
4803
4804 // Return a string used to fill a code section with nops.
4805 // For NaCl, long NOPs are only valid if they do not cross
4806 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4807 template<int size>
4808 std::string
4809 Target_x86_64_nacl<size>::do_code_fill(section_size_type length) const
4810 {
4811   return std::string(length, static_cast<char>(0x90));
4812 }
4813
4814 // The selector for x86_64-nacl object files.
4815
4816 template<int size>
4817 class Target_selector_x86_64_nacl
4818   : public Target_selector_nacl<Target_selector_x86_64<size>,
4819                                 Target_x86_64_nacl<size> >
4820 {
4821  public:
4822   Target_selector_x86_64_nacl()
4823     : Target_selector_nacl<Target_selector_x86_64<size>,
4824                            Target_x86_64_nacl<size> >("x86-64",
4825                                                       size == 64
4826                                                       ? "elf64-x86-64-nacl"
4827                                                       : "elf32-x86-64-nacl",
4828                                                       size == 64
4829                                                       ? "elf_x86_64_nacl"
4830                                                       : "elf32_x86_64_nacl")
4831   { }
4832 };
4833
4834 Target_selector_x86_64_nacl<64> target_selector_x86_64;
4835 Target_selector_x86_64_nacl<32> target_selector_x32;
4836
4837 } // End anonymous namespace.