gold/x86_64.cc

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