contrib/binutils-2.24/gold/x86_64.cc

   1 // x86_64.cc -- x86_64 target support for gold.
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
   4 // Free Software Foundation, Inc.
   5 // Written by Ian Lance Taylor <iant@google.com>.
   6
   7 // This file is part of gold.
   8
   9 // This program is free software; you can redistribute it and/or modify
  10 // it under the terms of the GNU General Public License as published by
  11 // the Free Software Foundation; either version 3 of the License, or
  12 // (at your option) any later version.
  13
  14 // This program is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18
  19 // You should have received a copy of the GNU General Public License
  20 // along with this program; if not, write to the Free Software
  21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  22 // MA 02110-1301, USA.
  23
  24 #include "gold.h"
  25
  26 #include <cstring>
  27
  28 #include "elfcpp.h"
  29 #include "dwarf.h"
  30 #include "parameters.h"
  31 #include "reloc.h"
  32 #include "x86_64.h"
  33 #include "object.h"
  34 #include "symtab.h"
  35 #include "layout.h"
  36 #include "output.h"
  37 #include "copy-relocs.h"
  38 #include "target.h"
  39 #include "target-reloc.h"
  40 #include "target-select.h"
  41 #include "tls.h"
  42 #include "freebsd.h"
  43 #include "nacl.h"
  44 #include "gc.h"
  45 #include "icf.h"
  46
  47 namespace
  48 {
  49
  50 using namespace gold;
  51
  52 // A class to handle the PLT data.
  53 // This is an abstract base class that handles most of the linker details
  54 // but does not know the actual contents of PLT entries.  The derived
  55 // classes below fill in those details.
  56
  57 template<int size>
  58 class Output_data_plt_x86_64 : public Output_section_data
  59 {
  60  public:
  61   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
  62
  63   Output_data_plt_x86_64(Layout* layout, uint64_t addralign,
  64                          Output_data_got<64, false>* got,
  65                          Output_data_space* got_plt,
  66                          Output_data_space* got_irelative)
  67     : Output_section_data(addralign), layout_(layout), tlsdesc_rel_(NULL),
  68       irelative_rel_(NULL), got_(got), got_plt_(got_plt),
  69       got_irelative_(got_irelative), count_(0), irelative_count_(0),
  70       tlsdesc_got_offset_(-1U), free_list_()
  71   { this->init(layout); }
  72
  73   Output_data_plt_x86_64(Layout* layout, uint64_t plt_entry_size,
  74                          Output_data_got<64, false>* got,
  75                          Output_data_space* got_plt,
  76                          Output_data_space* got_irelative,
  77                          unsigned int plt_count)
  78     : Output_section_data((plt_count + 1) * plt_entry_size,
  79                           plt_entry_size, false),
  80       layout_(layout), tlsdesc_rel_(NULL), irelative_rel_(NULL), got_(got),
  81       got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count),
  82       irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
  83   {
  84     this->init(layout);
  85
  86     // Initialize the free list and reserve the first entry.
  87     this->free_list_.init((plt_count + 1) * plt_entry_size, false);
  88     this->free_list_.remove(0, plt_entry_size);
  89   }
  90
  91   // Initialize the PLT section.
  92   void
  93   init(Layout* layout);
  94
  95   // Add an entry to the PLT.
  96   void
  97   add_entry(Symbol_table*, Layout*, Symbol* gsym);
  98
  99   // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
 100   unsigned int
 101   add_local_ifunc_entry(Symbol_table* symtab, Layout*,
 102                         Sized_relobj_file<size, false>* relobj,
 103                         unsigned int local_sym_index);
 104
 105   // Add the relocation for a PLT entry.
 106   void
 107   add_relocation(Symbol_table*, Layout*, Symbol* gsym,
 108                  unsigned int got_offset);
 109
 110   // Add the reserved TLSDESC_PLT entry to the PLT.
 111   void
 112   reserve_tlsdesc_entry(unsigned int got_offset)
 113   { this->tlsdesc_got_offset_ = got_offset; }
 114
 115   // Return true if a TLSDESC_PLT entry has been reserved.
 116   bool
 117   has_tlsdesc_entry() const
 118   { return this->tlsdesc_got_offset_ != -1U; }
 119
 120   // Return the GOT offset for the reserved TLSDESC_PLT entry.
 121   unsigned int
 122   get_tlsdesc_got_offset() const
 123   { return this->tlsdesc_got_offset_; }
 124
 125   // Return the offset of the reserved TLSDESC_PLT entry.
 126   unsigned int
 127   get_tlsdesc_plt_offset() const
 128   {
 129     return ((this->count_ + this->irelative_count_ + 1)
 130             * this->get_plt_entry_size());
 131   }
 132
 133   // Return the .rela.plt section data.
 134   Reloc_section*
 135   rela_plt()
 136   { return this->rel_; }
 137
 138   // Return where the TLSDESC relocations should go.
 139   Reloc_section*
 140   rela_tlsdesc(Layout*);
 141
 142   // Return where the IRELATIVE relocations should go in the PLT
 143   // relocations.
 144   Reloc_section*
 145   rela_irelative(Symbol_table*, Layout*);
 146
 147   // Return whether we created a section for IRELATIVE relocations.
 148   bool
 149   has_irelative_section() const
 150   { return this->irelative_rel_ != NULL; }
 151
 152   // Return the number of PLT entries.
 153   unsigned int
 154   entry_count() const
 155   { return this->count_ + this->irelative_count_; }
 156
 157   // Return the offset of the first non-reserved PLT entry.
 158   unsigned int
 159   first_plt_entry_offset()
 160   { return this->get_plt_entry_size(); }
 161
 162   // Return the size of a PLT entry.
 163   unsigned int
 164   get_plt_entry_size() const
 165   { return this->do_get_plt_entry_size(); }
 166
 167   // Reserve a slot in the PLT for an existing symbol in an incremental update.
 168   void
 169   reserve_slot(unsigned int plt_index)
 170   {
 171     this->free_list_.remove((plt_index + 1) * this->get_plt_entry_size(),
 172                             (plt_index + 2) * this->get_plt_entry_size());
 173   }
 174
 175   // Return the PLT address to use for a global symbol.
 176   uint64_t
 177   address_for_global(const Symbol*);
 178
 179   // Return the PLT address to use for a local symbol.
 180   uint64_t
 181   address_for_local(const Relobj*, unsigned int symndx);
 182
 183   // Add .eh_frame information for the PLT.
 184   void
 185   add_eh_frame(Layout* layout)
 186   { this->do_add_eh_frame(layout); }
 187
 188  protected:
 189   // Fill in the first PLT entry.
 190   void
 191   fill_first_plt_entry(unsigned char* pov,
 192                        typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 193                        typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
 194   { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
 195
 196   // Fill in a normal PLT entry.  Returns the offset into the entry that
 197   // should be the initial GOT slot value.
 198   unsigned int
 199   fill_plt_entry(unsigned char* pov,
 200                  typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 201                  typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 202                  unsigned int got_offset,
 203                  unsigned int plt_offset,
 204                  unsigned int plt_index)
 205   {
 206     return this->do_fill_plt_entry(pov, got_address, plt_address,
 207                                    got_offset, plt_offset, plt_index);
 208   }
 209
 210   // Fill in the reserved TLSDESC PLT entry.
 211   void
 212   fill_tlsdesc_entry(unsigned char* pov,
 213                      typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 214                      typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 215                      typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 216                      unsigned int tlsdesc_got_offset,
 217                      unsigned int plt_offset)
 218   {
 219     this->do_fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
 220                                 tlsdesc_got_offset, plt_offset);
 221   }
 222
 223   virtual unsigned int
 224   do_get_plt_entry_size() const = 0;
 225
 226   virtual void
 227   do_fill_first_plt_entry(unsigned char* pov,
 228                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
 229                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr)
 230     = 0;
 231
 232   virtual unsigned int
 233   do_fill_plt_entry(unsigned char* pov,
 234                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 235                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 236                     unsigned int got_offset,
 237                     unsigned int plt_offset,
 238                     unsigned int plt_index) = 0;
 239
 240   virtual void
 241   do_fill_tlsdesc_entry(unsigned char* pov,
 242                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 243                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 244                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 245                         unsigned int tlsdesc_got_offset,
 246                         unsigned int plt_offset) = 0;
 247
 248   virtual void
 249   do_add_eh_frame(Layout* layout) = 0;
 250
 251   void
 252   do_adjust_output_section(Output_section* os);
 253
 254   // Write to a map file.
 255   void
 256   do_print_to_mapfile(Mapfile* mapfile) const
 257   { mapfile->print_output_data(this, _("** PLT")); }
 258
 259   // The CIE of the .eh_frame unwind information for the PLT.
 260   static const int plt_eh_frame_cie_size = 16;
 261   static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
 262
 263  private:
 264   // Set the final size.
 265   void
 266   set_final_data_size();
 267
 268   // Write out the PLT data.
 269   void
 270   do_write(Output_file*);
 271
 272   // A pointer to the Layout class, so that we can find the .dynamic
 273   // section when we write out the GOT PLT section.
 274   Layout* layout_;
 275   // The reloc section.
 276   Reloc_section* rel_;
 277   // The TLSDESC relocs, if necessary.  These must follow the regular
 278   // PLT relocs.
 279   Reloc_section* tlsdesc_rel_;
 280   // The IRELATIVE relocs, if necessary.  These must follow the
 281   // regular PLT relocations and the TLSDESC relocations.
 282   Reloc_section* irelative_rel_;
 283   // The .got section.
 284   Output_data_got<64, false>* got_;
 285   // The .got.plt section.
 286   Output_data_space* got_plt_;
 287   // The part of the .got.plt section used for IRELATIVE relocs.
 288   Output_data_space* got_irelative_;
 289   // The number of PLT entries.
 290   unsigned int count_;
 291   // Number of PLT entries with R_X86_64_IRELATIVE relocs.  These
 292   // follow the regular PLT entries.
 293   unsigned int irelative_count_;
 294   // Offset of the reserved TLSDESC_GOT entry when needed.
 295   unsigned int tlsdesc_got_offset_;
 296   // List of available regions within the section, for incremental
 297   // update links.
 298   Free_list free_list_;
 299 };
 300
 301 template<int size>
 302 class Output_data_plt_x86_64_standard : public Output_data_plt_x86_64<size>
 303 {
 304  public:
 305   Output_data_plt_x86_64_standard(Layout* layout,
 306                                   Output_data_got<64, false>* got,
 307                                   Output_data_space* got_plt,
 308                                   Output_data_space* got_irelative)
 309     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 310                                    got, got_plt, got_irelative)
 311   { }
 312
 313   Output_data_plt_x86_64_standard(Layout* layout,
 314                                   Output_data_got<64, false>* got,
 315                                   Output_data_space* got_plt,
 316                                   Output_data_space* got_irelative,
 317                                   unsigned int plt_count)
 318     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 319                                    got, got_plt, got_irelative,
 320                                    plt_count)
 321   { }
 322
 323  protected:
 324   virtual unsigned int
 325   do_get_plt_entry_size() const
 326   { return plt_entry_size; }
 327
 328   virtual void
 329   do_add_eh_frame(Layout* layout)
 330   {
 331     layout->add_eh_frame_for_plt(this,
 332                                  this->plt_eh_frame_cie,
 333                                  this->plt_eh_frame_cie_size,
 334                                  plt_eh_frame_fde,
 335                                  plt_eh_frame_fde_size);
 336   }
 337
 338   virtual void
 339   do_fill_first_plt_entry(unsigned char* pov,
 340                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
 341                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
 342
 343   virtual unsigned int
 344   do_fill_plt_entry(unsigned char* pov,
 345                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 346                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 347                     unsigned int got_offset,
 348                     unsigned int plt_offset,
 349                     unsigned int plt_index);
 350
 351   virtual void
 352   do_fill_tlsdesc_entry(unsigned char* pov,
 353                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 354                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 355                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 356                         unsigned int tlsdesc_got_offset,
 357                         unsigned int plt_offset);
 358
 359  private:
 360   // The size of an entry in the PLT.
 361   static const int plt_entry_size = 16;
 362
 363   // The first entry in the PLT.
 364   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
 365   // procedure linkage table for both programs and shared objects."
 366   static const unsigned char first_plt_entry[plt_entry_size];
 367
 368   // Other entries in the PLT for an executable.
 369   static const unsigned char plt_entry[plt_entry_size];
 370
 371   // The reserved TLSDESC entry in the PLT for an executable.
 372   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
 373
 374   // The .eh_frame unwind information for the PLT.
 375   static const int plt_eh_frame_fde_size = 32;
 376   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
 377 };
 378
 379 // The x86_64 target class.
 380 // See the ABI at
 381 //   http://www.x86-64.org/documentation/abi.pdf
 382 // TLS info comes from
 383 //   http://people.redhat.com/drepper/tls.pdf
 384 //   http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
 385
 386 template<int size>
 387 class Target_x86_64 : public Sized_target<size, false>
 388 {
 389  public:
 390   // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
 391   // uses only Elf64_Rela relocation entries with explicit addends."
 392   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
 393
 394   Target_x86_64(const Target::Target_info* info = &x86_64_info)
 395     : Sized_target<size, false>(info),
 396       got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
 397       got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
 398       rela_irelative_(NULL), copy_relocs_(elfcpp::R_X86_64_COPY),
 399       got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
 400       tls_base_symbol_defined_(false)
 401   { }
 402
 403   // Hook for a new output section.
 404   void
 405   do_new_output_section(Output_section*) const;
 406
 407   // Scan the relocations to look for symbol adjustments.
 408   void
 409   gc_process_relocs(Symbol_table* symtab,
 410                     Layout* layout,
 411                     Sized_relobj_file<size, false>* object,
 412                     unsigned int data_shndx,
 413                     unsigned int sh_type,
 414                     const unsigned char* prelocs,
 415                     size_t reloc_count,
 416                     Output_section* output_section,
 417                     bool needs_special_offset_handling,
 418                     size_t local_symbol_count,
 419                     const unsigned char* plocal_symbols);
 420
 421   // Scan the relocations to look for symbol adjustments.
 422   void
 423   scan_relocs(Symbol_table* symtab,
 424               Layout* layout,
 425               Sized_relobj_file<size, false>* object,
 426               unsigned int data_shndx,
 427               unsigned int sh_type,
 428               const unsigned char* prelocs,
 429               size_t reloc_count,
 430               Output_section* output_section,
 431               bool needs_special_offset_handling,
 432               size_t local_symbol_count,
 433               const unsigned char* plocal_symbols);
 434
 435   // Finalize the sections.
 436   void
 437   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
 438
 439   // Return the value to use for a dynamic which requires special
 440   // treatment.
 441   uint64_t
 442   do_dynsym_value(const Symbol*) const;
 443
 444   // Relocate a section.
 445   void
 446   relocate_section(const Relocate_info<size, false>*,
 447                    unsigned int sh_type,
 448                    const unsigned char* prelocs,
 449                    size_t reloc_count,
 450                    Output_section* output_section,
 451                    bool needs_special_offset_handling,
 452                    unsigned char* view,
 453                    typename elfcpp::Elf_types<size>::Elf_Addr view_address,
 454                    section_size_type view_size,
 455                    const Reloc_symbol_changes*);
 456
 457   // Scan the relocs during a relocatable link.
 458   void
 459   scan_relocatable_relocs(Symbol_table* symtab,
 460                           Layout* layout,
 461                           Sized_relobj_file<size, false>* object,
 462                           unsigned int data_shndx,
 463                           unsigned int sh_type,
 464                           const unsigned char* prelocs,
 465                           size_t reloc_count,
 466                           Output_section* output_section,
 467                           bool needs_special_offset_handling,
 468                           size_t local_symbol_count,
 469                           const unsigned char* plocal_symbols,
 470                           Relocatable_relocs*);
 471
 472   // Emit relocations for a section.
 473   void
 474   relocate_relocs(
 475       const Relocate_info<size, false>*,
 476       unsigned int sh_type,
 477       const unsigned char* prelocs,
 478       size_t reloc_count,
 479       Output_section* output_section,
 480       typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
 481       const Relocatable_relocs*,
 482       unsigned char* view,
 483       typename elfcpp::Elf_types<size>::Elf_Addr view_address,
 484       section_size_type view_size,
 485       unsigned char* reloc_view,
 486       section_size_type reloc_view_size);
 487
 488   // Return a string used to fill a code section with nops.
 489   std::string
 490   do_code_fill(section_size_type length) const;
 491
 492   // Return whether SYM is defined by the ABI.
 493   bool
 494   do_is_defined_by_abi(const Symbol* sym) const
 495   { return strcmp(sym->name(), "__tls_get_addr") == 0; }
 496
 497   // Return the symbol index to use for a target specific relocation.
 498   // The only target specific relocation is R_X86_64_TLSDESC for a
 499   // local symbol, which is an absolute reloc.
 500   unsigned int
 501   do_reloc_symbol_index(void*, unsigned int r_type) const
 502   {
 503     gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
 504     return 0;
 505   }
 506
 507   // Return the addend to use for a target specific relocation.
 508   uint64_t
 509   do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
 510
 511   // Return the PLT section.
 512   uint64_t
 513   do_plt_address_for_global(const Symbol* gsym) const
 514   { return this->plt_section()->address_for_global(gsym); }
 515
 516   uint64_t
 517   do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
 518   { return this->plt_section()->address_for_local(relobj, symndx); }
 519
 520   // This function should be defined in targets that can use relocation
 521   // types to determine (implemented in local_reloc_may_be_function_pointer
 522   // and global_reloc_may_be_function_pointer)
 523   // if a function's pointer is taken.  ICF uses this in safe mode to only
 524   // fold those functions whose pointer is defintely not taken.  For x86_64
 525   // pie binaries, safe ICF cannot be done by looking at relocation types.
 526   bool
 527   do_can_check_for_function_pointers() const
 528   { return !parameters->options().pie(); }
 529
 530   // Return the base for a DW_EH_PE_datarel encoding.
 531   uint64_t
 532   do_ehframe_datarel_base() const;
 533
 534   // Adjust -fsplit-stack code which calls non-split-stack code.
 535   void
 536   do_calls_non_split(Relobj* object, unsigned int shndx,
 537                      section_offset_type fnoffset, section_size_type fnsize,
 538                      unsigned char* view, section_size_type view_size,
 539                      std::string* from, std::string* to) const;
 540
 541   // Return the size of the GOT section.
 542   section_size_type
 543   got_size() const
 544   {
 545     gold_assert(this->got_ != NULL);
 546     return this->got_->data_size();
 547   }
 548
 549   // Return the number of entries in the GOT.
 550   unsigned int
 551   got_entry_count() const
 552   {
 553     if (this->got_ == NULL)
 554       return 0;
 555     return this->got_size() / 8;
 556   }
 557
 558   // Return the number of entries in the PLT.
 559   unsigned int
 560   plt_entry_count() const;
 561
 562   // Return the offset of the first non-reserved PLT entry.
 563   unsigned int
 564   first_plt_entry_offset() const;
 565
 566   // Return the size of each PLT entry.
 567   unsigned int
 568   plt_entry_size() const;
 569
 570   // Create the GOT section for an incremental update.
 571   Output_data_got_base*
 572   init_got_plt_for_update(Symbol_table* symtab,
 573                           Layout* layout,
 574                           unsigned int got_count,
 575                           unsigned int plt_count);
 576
 577   // Reserve a GOT entry for a local symbol, and regenerate any
 578   // necessary dynamic relocations.
 579   void
 580   reserve_local_got_entry(unsigned int got_index,
 581                           Sized_relobj<size, false>* obj,
 582                           unsigned int r_sym,
 583                           unsigned int got_type);
 584
 585   // Reserve a GOT entry for a global symbol, and regenerate any
 586   // necessary dynamic relocations.
 587   void
 588   reserve_global_got_entry(unsigned int got_index, Symbol* gsym,
 589                            unsigned int got_type);
 590
 591   // Register an existing PLT entry for a global symbol.
 592   void
 593   register_global_plt_entry(Symbol_table*, Layout*, unsigned int plt_index,
 594                             Symbol* gsym);
 595
 596   // Force a COPY relocation for a given symbol.
 597   void
 598   emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t);
 599
 600   // Apply an incremental relocation.
 601   void
 602   apply_relocation(const Relocate_info<size, false>* relinfo,
 603                    typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
 604                    unsigned int r_type,
 605                    typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
 606                    const Symbol* gsym,
 607                    unsigned char* view,
 608                    typename elfcpp::Elf_types<size>::Elf_Addr address,
 609                    section_size_type view_size);
 610
 611   // Add a new reloc argument, returning the index in the vector.
 612   size_t
 613   add_tlsdesc_info(Sized_relobj_file<size, false>* object, unsigned int r_sym)
 614   {
 615     this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
 616     return this->tlsdesc_reloc_info_.size() - 1;
 617   }
 618
 619   Output_data_plt_x86_64<size>*
 620   make_data_plt(Layout* layout,
 621                 Output_data_got<64, false>* got,
 622                 Output_data_space* got_plt,
 623                 Output_data_space* got_irelative)
 624   {
 625     return this->do_make_data_plt(layout, got, got_plt, got_irelative);
 626   }
 627
 628   Output_data_plt_x86_64<size>*
 629   make_data_plt(Layout* layout,
 630                 Output_data_got<64, false>* got,
 631                 Output_data_space* got_plt,
 632                 Output_data_space* got_irelative,
 633                 unsigned int plt_count)
 634   {
 635     return this->do_make_data_plt(layout, got, got_plt, got_irelative,
 636                                   plt_count);
 637   }
 638
 639   virtual Output_data_plt_x86_64<size>*
 640   do_make_data_plt(Layout* layout,
 641                    Output_data_got<64, false>* got,
 642                    Output_data_space* got_plt,
 643                    Output_data_space* got_irelative)
 644   {
 645     return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
 646                                                      got_irelative);
 647   }
 648
 649   virtual Output_data_plt_x86_64<size>*
 650   do_make_data_plt(Layout* layout,
 651                    Output_data_got<64, false>* got,
 652                    Output_data_space* got_plt,
 653                    Output_data_space* got_irelative,
 654                    unsigned int plt_count)
 655   {
 656     return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
 657                                                      got_irelative,
 658                                                      plt_count);
 659   }
 660
 661  private:
 662   // The class which scans relocations.
 663   class Scan
 664   {
 665   public:
 666     Scan()
 667       : issued_non_pic_error_(false)
 668     { }
 669
 670     static inline int
 671     get_reference_flags(unsigned int r_type);
 672
 673     inline void
 674     local(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
 675           Sized_relobj_file<size, false>* object,
 676           unsigned int data_shndx,
 677           Output_section* output_section,
 678           const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
 679           const elfcpp::Sym<size, false>& lsym,
 680           bool is_discarded);
 681
 682     inline void
 683     global(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
 684            Sized_relobj_file<size, false>* object,
 685            unsigned int data_shndx,
 686            Output_section* output_section,
 687            const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
 688            Symbol* gsym);
 689
 690     inline bool
 691     local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
 692                                         Target_x86_64* target,
 693                                         Sized_relobj_file<size, false>* object,
 694                                         unsigned int data_shndx,
 695                                         Output_section* output_section,
 696                                         const elfcpp::Rela<size, false>& reloc,
 697                                         unsigned int r_type,
 698                                         const elfcpp::Sym<size, false>& lsym);
 699
 700     inline bool
 701     global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
 702                                          Target_x86_64* target,
 703                                          Sized_relobj_file<size, false>* object,
 704                                          unsigned int data_shndx,
 705                                          Output_section* output_section,
 706                                          const elfcpp::Rela<size, false>& reloc,
 707                                          unsigned int r_type,
 708                                          Symbol* gsym);
 709
 710   private:
 711     static void
 712     unsupported_reloc_local(Sized_relobj_file<size, false>*,
 713                             unsigned int r_type);
 714
 715     static void
 716     unsupported_reloc_global(Sized_relobj_file<size, false>*,
 717                              unsigned int r_type, Symbol*);
 718
 719     void
 720     check_non_pic(Relobj*, unsigned int r_type, Symbol*);
 721
 722     inline bool
 723     possible_function_pointer_reloc(unsigned int r_type);
 724
 725     bool
 726     reloc_needs_plt_for_ifunc(Sized_relobj_file<size, false>*,
 727                               unsigned int r_type);
 728
 729     // Whether we have issued an error about a non-PIC compilation.
 730     bool issued_non_pic_error_;
 731   };
 732
 733   // The class which implements relocation.
 734   class Relocate
 735   {
 736    public:
 737     Relocate()
 738       : skip_call_tls_get_addr_(false)
 739     { }
 740
 741     ~Relocate()
 742     {
 743       if (this->skip_call_tls_get_addr_)
 744         {
 745           // FIXME: This needs to specify the location somehow.
 746           gold_error(_("missing expected TLS relocation"));
 747         }
 748     }
 749
 750     // Do a relocation.  Return false if the caller should not issue
 751     // any warnings about this relocation.
 752     inline bool
 753     relocate(const Relocate_info<size, false>*, Target_x86_64*,
 754              Output_section*,
 755              size_t relnum, const elfcpp::Rela<size, false>&,
 756              unsigned int r_type, const Sized_symbol<size>*,
 757              const Symbol_value<size>*,
 758              unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
 759              section_size_type);
 760
 761    private:
 762     // Do a TLS relocation.
 763     inline void
 764     relocate_tls(const Relocate_info<size, false>*, Target_x86_64*,
 765                  size_t relnum, const elfcpp::Rela<size, false>&,
 766                  unsigned int r_type, const Sized_symbol<size>*,
 767                  const Symbol_value<size>*,
 768                  unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
 769                  section_size_type);
 770
 771     // Do a TLS General-Dynamic to Initial-Exec transition.
 772     inline void
 773     tls_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
 774                  Output_segment* tls_segment,
 775                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 776                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 777                  unsigned char* view,
 778                  typename elfcpp::Elf_types<size>::Elf_Addr,
 779                  section_size_type view_size);
 780
 781     // Do a TLS General-Dynamic to Local-Exec transition.
 782     inline void
 783     tls_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
 784                  Output_segment* tls_segment,
 785                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 786                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 787                  unsigned char* view,
 788                  section_size_type view_size);
 789
 790     // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
 791     inline void
 792     tls_desc_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
 793                       Output_segment* tls_segment,
 794                       const elfcpp::Rela<size, false>&, unsigned int r_type,
 795                       typename elfcpp::Elf_types<size>::Elf_Addr value,
 796                       unsigned char* view,
 797                       typename elfcpp::Elf_types<size>::Elf_Addr,
 798                       section_size_type view_size);
 799
 800     // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
 801     inline void
 802     tls_desc_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
 803                       Output_segment* tls_segment,
 804                       const elfcpp::Rela<size, false>&, unsigned int r_type,
 805                       typename elfcpp::Elf_types<size>::Elf_Addr value,
 806                       unsigned char* view,
 807                       section_size_type view_size);
 808
 809     // Do a TLS Local-Dynamic to Local-Exec transition.
 810     inline void
 811     tls_ld_to_le(const Relocate_info<size, false>*, size_t relnum,
 812                  Output_segment* tls_segment,
 813                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 814                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 815                  unsigned char* view,
 816                  section_size_type view_size);
 817
 818     // Do a TLS Initial-Exec to Local-Exec transition.
 819     static inline void
 820     tls_ie_to_le(const Relocate_info<size, false>*, size_t relnum,
 821                  Output_segment* tls_segment,
 822                  const elfcpp::Rela<size, false>&, unsigned int r_type,
 823                  typename elfcpp::Elf_types<size>::Elf_Addr value,
 824                  unsigned char* view,
 825                  section_size_type view_size);
 826
 827     // This is set if we should skip the next reloc, which should be a
 828     // PLT32 reloc against ___tls_get_addr.
 829     bool skip_call_tls_get_addr_;
 830   };
 831
 832   // A class which returns the size required for a relocation type,
 833   // used while scanning relocs during a relocatable link.
 834   class Relocatable_size_for_reloc
 835   {
 836    public:
 837     unsigned int
 838     get_size_for_reloc(unsigned int, Relobj*);
 839   };
 840
 841   // Adjust TLS relocation type based on the options and whether this
 842   // is a local symbol.
 843   static tls::Tls_optimization
 844   optimize_tls_reloc(bool is_final, int r_type);
 845
 846   // Get the GOT section, creating it if necessary.
 847   Output_data_got<64, false>*
 848   got_section(Symbol_table*, Layout*);
 849
 850   // Get the GOT PLT section.
 851   Output_data_space*
 852   got_plt_section() const
 853   {
 854     gold_assert(this->got_plt_ != NULL);
 855     return this->got_plt_;
 856   }
 857
 858   // Get the GOT section for TLSDESC entries.
 859   Output_data_got<64, false>*
 860   got_tlsdesc_section() const
 861   {
 862     gold_assert(this->got_tlsdesc_ != NULL);
 863     return this->got_tlsdesc_;
 864   }
 865
 866   // Create the PLT section.
 867   void
 868   make_plt_section(Symbol_table* symtab, Layout* layout);
 869
 870   // Create a PLT entry for a global symbol.
 871   void
 872   make_plt_entry(Symbol_table*, Layout*, Symbol*);
 873
 874   // Create a PLT entry for a local STT_GNU_IFUNC symbol.
 875   void
 876   make_local_ifunc_plt_entry(Symbol_table*, Layout*,
 877                              Sized_relobj_file<size, false>* relobj,
 878                              unsigned int local_sym_index);
 879
 880   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
 881   void
 882   define_tls_base_symbol(Symbol_table*, Layout*);
 883
 884   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
 885   void
 886   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
 887
 888   // Create a GOT entry for the TLS module index.
 889   unsigned int
 890   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
 891                       Sized_relobj_file<size, false>* object);
 892
 893   // Get the PLT section.
 894   Output_data_plt_x86_64<size>*
 895   plt_section() const
 896   {
 897     gold_assert(this->plt_ != NULL);
 898     return this->plt_;
 899   }
 900
 901   // Get the dynamic reloc section, creating it if necessary.
 902   Reloc_section*
 903   rela_dyn_section(Layout*);
 904
 905   // Get the section to use for TLSDESC relocations.
 906   Reloc_section*
 907   rela_tlsdesc_section(Layout*) const;
 908
 909   // Get the section to use for IRELATIVE relocations.
 910   Reloc_section*
 911   rela_irelative_section(Layout*);
 912
 913   // Add a potential copy relocation.
 914   void
 915   copy_reloc(Symbol_table* symtab, Layout* layout,
 916              Sized_relobj_file<size, false>* object,
 917              unsigned int shndx, Output_section* output_section,
 918              Symbol* sym, const elfcpp::Rela<size, false>& reloc)
 919   {
 920     this->copy_relocs_.copy_reloc(symtab, layout,
 921                                   symtab->get_sized_symbol<size>(sym),
 922                                   object, shndx, output_section,
 923                                   reloc, this->rela_dyn_section(layout));
 924   }
 925
 926   // Information about this specific target which we pass to the
 927   // general Target structure.
 928   static const Target::Target_info x86_64_info;
 929
 930   // The types of GOT entries needed for this platform.
 931   // These values are exposed to the ABI in an incremental link.
 932   // Do not renumber existing values without changing the version
 933   // number of the .gnu_incremental_inputs section.
 934   enum Got_type
 935   {
 936     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
 937     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
 938     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
 939     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
 940   };
 941
 942   // This type is used as the argument to the target specific
 943   // relocation routines.  The only target specific reloc is
 944   // R_X86_64_TLSDESC against a local symbol.
 945   struct Tlsdesc_info
 946   {
 947     Tlsdesc_info(Sized_relobj_file<size, false>* a_object, unsigned int a_r_sym)
 948       : object(a_object), r_sym(a_r_sym)
 949     { }
 950
 951     // The object in which the local symbol is defined.
 952     Sized_relobj_file<size, false>* object;
 953     // The local symbol index in the object.
 954     unsigned int r_sym;
 955   };
 956
 957   // The GOT section.
 958   Output_data_got<64, false>* got_;
 959   // The PLT section.
 960   Output_data_plt_x86_64<size>* plt_;
 961   // The GOT PLT section.
 962   Output_data_space* got_plt_;
 963   // The GOT section for IRELATIVE relocations.
 964   Output_data_space* got_irelative_;
 965   // The GOT section for TLSDESC relocations.
 966   Output_data_got<64, false>* got_tlsdesc_;
 967   // The _GLOBAL_OFFSET_TABLE_ symbol.
 968   Symbol* global_offset_table_;
 969   // The dynamic reloc section.
 970   Reloc_section* rela_dyn_;
 971   // The section to use for IRELATIVE relocs.
 972   Reloc_section* rela_irelative_;
 973   // Relocs saved to avoid a COPY reloc.
 974   Copy_relocs<elfcpp::SHT_RELA, size, false> copy_relocs_;
 975   // Offset of the GOT entry for the TLS module index.
 976   unsigned int got_mod_index_offset_;
 977   // We handle R_X86_64_TLSDESC against a local symbol as a target
 978   // specific relocation.  Here we store the object and local symbol
 979   // index for the relocation.
 980   std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
 981   // True if the _TLS_MODULE_BASE_ symbol has been defined.
 982   bool tls_base_symbol_defined_;
 983 };
 984
 985 template<>
 986 const Target::Target_info Target_x86_64<64>::x86_64_info =
 987 {
 988   64,                   // size
 989   false,                // is_big_endian
 990   elfcpp::EM_X86_64,    // machine_code
 991   false,                // has_make_symbol
 992   false,                // has_resolve
 993   true,                 // has_code_fill
 994   true,                 // is_default_stack_executable
 995   true,                 // can_icf_inline_merge_sections
 996   '\0',                 // wrap_char
 997   "/lib/ld64.so.1",     // program interpreter
 998   0x400000,             // default_text_segment_address
 999   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1000   0x1000,               // common_pagesize (overridable by -z common-page-size)
1001   false,                // isolate_execinstr
1002   0,                    // rosegment_gap
1003   elfcpp::SHN_UNDEF,    // small_common_shndx
1004   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1005   0,                    // small_common_section_flags
1006   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1007   NULL,                 // attributes_section
1008   NULL,                 // attributes_vendor
1009   "_start"              // entry_symbol_name
1010 };
1011
1012 template<>
1013 const Target::Target_info Target_x86_64<32>::x86_64_info =
1014 {
1015   32,                   // size
1016   false,                // is_big_endian
1017   elfcpp::EM_X86_64,    // machine_code
1018   false,                // has_make_symbol
1019   false,                // has_resolve
1020   true,                 // has_code_fill
1021   true,                 // is_default_stack_executable
1022   true,                 // can_icf_inline_merge_sections
1023   '\0',                 // wrap_char
1024   "/libx32/ldx32.so.1", // program interpreter
1025   0x400000,             // default_text_segment_address
1026   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1027   0x1000,               // common_pagesize (overridable by -z common-page-size)
1028   false,                // isolate_execinstr
1029   0,                    // rosegment_gap
1030   elfcpp::SHN_UNDEF,    // small_common_shndx
1031   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1032   0,                    // small_common_section_flags
1033   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1034   NULL,                 // attributes_section
1035   NULL,                 // attributes_vendor
1036   "_start"              // entry_symbol_name
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 + gsym->plt_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* object,
1397                                                 unsigned int r_sym)
1398 {
1399   return (this->address()
1400           + (this->count_ + 1) * this->get_plt_entry_size()
1401           + object->local_plt_offset(r_sym));
1402 }
1403
1404 // Set the final size.
1405 template<int size>
1406 void
1407 Output_data_plt_x86_64<size>::set_final_data_size()
1408 {
1409   unsigned int count = this->count_ + this->irelative_count_;
1410   if (this->has_tlsdesc_entry())
1411     ++count;
1412   this->set_data_size((count + 1) * this->get_plt_entry_size());
1413 }
1414
1415 // The first entry in the PLT for an executable.
1416
1417 template<int size>
1418 const unsigned char
1419 Output_data_plt_x86_64_standard<size>::first_plt_entry[plt_entry_size] =
1420 {
1421   // From AMD64 ABI Draft 0.98, page 76
1422   0xff, 0x35,   // pushq contents of memory address
1423   0, 0, 0, 0,   // replaced with address of .got + 8
1424   0xff, 0x25,   // jmp indirect
1425   0, 0, 0, 0,   // replaced with address of .got + 16
1426   0x90, 0x90, 0x90, 0x90   // noop (x4)
1427 };
1428
1429 template<int size>
1430 void
1431 Output_data_plt_x86_64_standard<size>::do_fill_first_plt_entry(
1432     unsigned char* pov,
1433     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1434     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
1435 {
1436   memcpy(pov, first_plt_entry, plt_entry_size);
1437   // We do a jmp relative to the PC at the end of this instruction.
1438   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1439                                               (got_address + 8
1440                                                - (plt_address + 6)));
1441   elfcpp::Swap<32, false>::writeval(pov + 8,
1442                                     (got_address + 16
1443                                      - (plt_address + 12)));
1444 }
1445
1446 // Subsequent entries in the PLT for an executable.
1447
1448 template<int size>
1449 const unsigned char
1450 Output_data_plt_x86_64_standard<size>::plt_entry[plt_entry_size] =
1451 {
1452   // From AMD64 ABI Draft 0.98, page 76
1453   0xff, 0x25,   // jmpq indirect
1454   0, 0, 0, 0,   // replaced with address of symbol in .got
1455   0x68,         // pushq immediate
1456   0, 0, 0, 0,   // replaced with offset into relocation table
1457   0xe9,         // jmpq relative
1458   0, 0, 0, 0    // replaced with offset to start of .plt
1459 };
1460
1461 template<int size>
1462 unsigned int
1463 Output_data_plt_x86_64_standard<size>::do_fill_plt_entry(
1464     unsigned char* pov,
1465     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1466     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1467     unsigned int got_offset,
1468     unsigned int plt_offset,
1469     unsigned int plt_index)
1470 {
1471   memcpy(pov, plt_entry, plt_entry_size);
1472   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1473                                               (got_address + got_offset
1474                                                - (plt_address + plt_offset
1475                                                   + 6)));
1476
1477   elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
1478   elfcpp::Swap<32, false>::writeval(pov + 12,
1479                                     - (plt_offset + plt_entry_size));
1480
1481   return 6;
1482 }
1483
1484 // The reserved TLSDESC entry in the PLT for an executable.
1485
1486 template<int size>
1487 const unsigned char
1488 Output_data_plt_x86_64_standard<size>::tlsdesc_plt_entry[plt_entry_size] =
1489 {
1490   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1491   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1492   0xff, 0x35,   // pushq x(%rip)
1493   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1494   0xff, 0x25,   // jmpq *y(%rip)
1495   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
1496   0x0f, 0x1f,   // nop
1497   0x40, 0
1498 };
1499
1500 template<int size>
1501 void
1502 Output_data_plt_x86_64_standard<size>::do_fill_tlsdesc_entry(
1503     unsigned char* pov,
1504     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1505     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1506     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
1507     unsigned int tlsdesc_got_offset,
1508     unsigned int plt_offset)
1509 {
1510   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
1511   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1512                                               (got_address + 8
1513                                                - (plt_address + plt_offset
1514                                                   + 6)));
1515   elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
1516                                               (got_base
1517                                                + tlsdesc_got_offset
1518                                                - (plt_address + plt_offset
1519                                                   + 12)));
1520 }
1521
1522 // The .eh_frame unwind information for the PLT.
1523
1524 template<int size>
1525 const unsigned char
1526 Output_data_plt_x86_64<size>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1527 {
1528   1,                            // CIE version.
1529   'z',                          // Augmentation: augmentation size included.
1530   'R',                          // Augmentation: FDE encoding included.
1531   '\0',                         // End of augmentation string.
1532   1,                            // Code alignment factor.
1533   0x78,                         // Data alignment factor.
1534   16,                           // Return address column.
1535   1,                            // Augmentation size.
1536   (elfcpp::DW_EH_PE_pcrel       // FDE encoding.
1537    | elfcpp::DW_EH_PE_sdata4),
1538   elfcpp::DW_CFA_def_cfa, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1539   elfcpp::DW_CFA_offset + 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1540   elfcpp::DW_CFA_nop,           // Align to 16 bytes.
1541   elfcpp::DW_CFA_nop
1542 };
1543
1544 template<int size>
1545 const unsigned char
1546 Output_data_plt_x86_64_standard<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1547 {
1548   0, 0, 0, 0,                           // Replaced with offset to .plt.
1549   0, 0, 0, 0,                           // Replaced with size of .plt.
1550   0,                                    // Augmentation size.
1551   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
1552   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
1553   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
1554   elfcpp::DW_CFA_advance_loc + 10,      // Advance 10 to __PLT__ + 16.
1555   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
1556   11,                                   // Block length.
1557   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
1558   elfcpp::DW_OP_breg16, 0,              // Push %rip.
1559   elfcpp::DW_OP_lit15,                  // Push 0xf.
1560   elfcpp::DW_OP_and,                    // & (%rip & 0xf).
1561   elfcpp::DW_OP_lit11,                  // Push 0xb.
1562   elfcpp::DW_OP_ge,                     // >= ((%rip & 0xf) >= 0xb)
1563   elfcpp::DW_OP_lit3,                   // Push 3.
1564   elfcpp::DW_OP_shl,                    // << (((%rip & 0xf) >= 0xb) << 3)
1565   elfcpp::DW_OP_plus,                   // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1566   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
1567   elfcpp::DW_CFA_nop,
1568   elfcpp::DW_CFA_nop,
1569   elfcpp::DW_CFA_nop
1570 };
1571
1572 // Write out the PLT.  This uses the hand-coded instructions above,
1573 // and adjusts them as needed.  This is specified by the AMD64 ABI.
1574
1575 template<int size>
1576 void
1577 Output_data_plt_x86_64<size>::do_write(Output_file* of)
1578 {
1579   const off_t offset = this->offset();
1580   const section_size_type oview_size =
1581     convert_to_section_size_type(this->data_size());
1582   unsigned char* const oview = of->get_output_view(offset, oview_size);
1583
1584   const off_t got_file_offset = this->got_plt_->offset();
1585   gold_assert(parameters->incremental_update()
1586               || (got_file_offset + this->got_plt_->data_size()
1587                   == this->got_irelative_->offset()));
1588   const section_size_type got_size =
1589     convert_to_section_size_type(this->got_plt_->data_size()
1590                                  + this->got_irelative_->data_size());
1591   unsigned char* const got_view = of->get_output_view(got_file_offset,
1592                                                       got_size);
1593
1594   unsigned char* pov = oview;
1595
1596   // The base address of the .plt section.
1597   typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
1598   // The base address of the .got section.
1599   typename elfcpp::Elf_types<size>::Elf_Addr got_base = this->got_->address();
1600   // The base address of the PLT portion of the .got section,
1601   // which is where the GOT pointer will point, and where the
1602   // three reserved GOT entries are located.
1603   typename elfcpp::Elf_types<size>::Elf_Addr got_address
1604     = this->got_plt_->address();
1605
1606   this->fill_first_plt_entry(pov, got_address, plt_address);
1607   pov += this->get_plt_entry_size();
1608
1609   unsigned char* got_pov = got_view;
1610
1611   // The first entry in the GOT is the address of the .dynamic section
1612   // aka the PT_DYNAMIC segment.  The next two entries are reserved.
1613   // We saved space for them when we created the section in
1614   // Target_x86_64::got_section.
1615   Output_section* dynamic = this->layout_->dynamic_section();
1616   uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1617   elfcpp::Swap<64, false>::writeval(got_pov, dynamic_addr);
1618   got_pov += 8;
1619   memset(got_pov, 0, 16);
1620   got_pov += 16;
1621
1622   unsigned int plt_offset = this->get_plt_entry_size();
1623   unsigned int got_offset = 24;
1624   const unsigned int count = this->count_ + this->irelative_count_;
1625   for (unsigned int plt_index = 0;
1626        plt_index < count;
1627        ++plt_index,
1628          pov += this->get_plt_entry_size(),
1629          got_pov += 8,
1630          plt_offset += this->get_plt_entry_size(),
1631          got_offset += 8)
1632     {
1633       // Set and adjust the PLT entry itself.
1634       unsigned int lazy_offset = this->fill_plt_entry(pov,
1635                                                       got_address, plt_address,
1636                                                       got_offset, plt_offset,
1637                                                       plt_index);
1638
1639       // Set the entry in the GOT.
1640       elfcpp::Swap<64, false>::writeval(got_pov,
1641                                         plt_address + plt_offset + lazy_offset);
1642     }
1643
1644   if (this->has_tlsdesc_entry())
1645     {
1646       // Set and adjust the reserved TLSDESC PLT entry.
1647       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
1648       this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
1649                                tlsdesc_got_offset, plt_offset);
1650       pov += this->get_plt_entry_size();
1651     }
1652
1653   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1654   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1655
1656   of->write_output_view(offset, oview_size, oview);
1657   of->write_output_view(got_file_offset, got_size, got_view);
1658 }
1659
1660 // Create the PLT section.
1661
1662 template<int size>
1663 void
1664 Target_x86_64<size>::make_plt_section(Symbol_table* symtab, Layout* layout)
1665 {
1666   if (this->plt_ == NULL)
1667     {
1668       // Create the GOT sections first.
1669       this->got_section(symtab, layout);
1670
1671       this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
1672                                        this->got_irelative_);
1673
1674       // Add unwind information if requested.
1675       if (parameters->options().ld_generated_unwind_info())
1676         this->plt_->add_eh_frame(layout);
1677
1678       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1679                                       (elfcpp::SHF_ALLOC
1680                                        | elfcpp::SHF_EXECINSTR),
1681                                       this->plt_, ORDER_PLT, false);
1682
1683       // Make the sh_info field of .rela.plt point to .plt.
1684       Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1685       rela_plt_os->set_info_section(this->plt_->output_section());
1686     }
1687 }
1688
1689 // Return the section for TLSDESC relocations.
1690
1691 template<int size>
1692 typename Target_x86_64<size>::Reloc_section*
1693 Target_x86_64<size>::rela_tlsdesc_section(Layout* layout) const
1694 {
1695   return this->plt_section()->rela_tlsdesc(layout);
1696 }
1697
1698 // Create a PLT entry for a global symbol.
1699
1700 template<int size>
1701 void
1702 Target_x86_64<size>::make_plt_entry(Symbol_table* symtab, Layout* layout,
1703                                     Symbol* gsym)
1704 {
1705   if (gsym->has_plt_offset())
1706     return;
1707
1708   if (this->plt_ == NULL)
1709     this->make_plt_section(symtab, layout);
1710
1711   this->plt_->add_entry(symtab, layout, gsym);
1712 }
1713
1714 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1715
1716 template<int size>
1717 void
1718 Target_x86_64<size>::make_local_ifunc_plt_entry(
1719     Symbol_table* symtab, Layout* layout,
1720     Sized_relobj_file<size, false>* relobj,
1721     unsigned int local_sym_index)
1722 {
1723   if (relobj->local_has_plt_offset(local_sym_index))
1724     return;
1725   if (this->plt_ == NULL)
1726     this->make_plt_section(symtab, layout);
1727   unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1728                                                               relobj,
1729                                                               local_sym_index);
1730   relobj->set_local_plt_offset(local_sym_index, plt_offset);
1731 }
1732
1733 // Return the number of entries in the PLT.
1734
1735 template<int size>
1736 unsigned int
1737 Target_x86_64<size>::plt_entry_count() const
1738 {
1739   if (this->plt_ == NULL)
1740     return 0;
1741   return this->plt_->entry_count();
1742 }
1743
1744 // Return the offset of the first non-reserved PLT entry.
1745
1746 template<int size>
1747 unsigned int
1748 Target_x86_64<size>::first_plt_entry_offset() const
1749 {
1750   return this->plt_->first_plt_entry_offset();
1751 }
1752
1753 // Return the size of each PLT entry.
1754
1755 template<int size>
1756 unsigned int
1757 Target_x86_64<size>::plt_entry_size() const
1758 {
1759   return this->plt_->get_plt_entry_size();
1760 }
1761
1762 // Create the GOT and PLT sections for an incremental update.
1763
1764 template<int size>
1765 Output_data_got_base*
1766 Target_x86_64<size>::init_got_plt_for_update(Symbol_table* symtab,
1767                                        Layout* layout,
1768                                        unsigned int got_count,
1769                                        unsigned int plt_count)
1770 {
1771   gold_assert(this->got_ == NULL);
1772
1773   this->got_ = new Output_data_got<64, false>(got_count * 8);
1774   layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1775                                   (elfcpp::SHF_ALLOC
1776                                    | elfcpp::SHF_WRITE),
1777                                   this->got_, ORDER_RELRO_LAST,
1778                                   true);
1779
1780   // Add the three reserved entries.
1781   this->got_plt_ = new Output_data_space((plt_count + 3) * 8, 8, "** GOT PLT");
1782   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1783                                   (elfcpp::SHF_ALLOC
1784                                    | elfcpp::SHF_WRITE),
1785                                   this->got_plt_, ORDER_NON_RELRO_FIRST,
1786                                   false);
1787
1788   // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1789   this->global_offset_table_ =
1790     symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1791                                   Symbol_table::PREDEFINED,
1792                                   this->got_plt_,
1793                                   0, 0, elfcpp::STT_OBJECT,
1794                                   elfcpp::STB_LOCAL,
1795                                   elfcpp::STV_HIDDEN, 0,
1796                                   false, false);
1797
1798   // If there are any TLSDESC relocations, they get GOT entries in
1799   // .got.plt after the jump slot entries.
1800   // FIXME: Get the count for TLSDESC entries.
1801   this->got_tlsdesc_ = new Output_data_got<64, false>(0);
1802   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1803                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1804                                   this->got_tlsdesc_,
1805                                   ORDER_NON_RELRO_FIRST, false);
1806
1807   // If there are any IRELATIVE relocations, they get GOT entries in
1808   // .got.plt after the jump slot and TLSDESC entries.
1809   this->got_irelative_ = new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1810   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1811                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1812                                   this->got_irelative_,
1813                                   ORDER_NON_RELRO_FIRST, false);
1814
1815   // Create the PLT section.
1816   this->plt_ = this->make_data_plt(layout, this->got_,
1817                                    this->got_plt_,
1818                                    this->got_irelative_,
1819                                    plt_count);
1820
1821   // Add unwind information if requested.
1822   if (parameters->options().ld_generated_unwind_info())
1823     this->plt_->add_eh_frame(layout);
1824
1825   layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1826                                   elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
1827                                   this->plt_, ORDER_PLT, false);
1828
1829   // Make the sh_info field of .rela.plt point to .plt.
1830   Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1831   rela_plt_os->set_info_section(this->plt_->output_section());
1832
1833   // Create the rela_dyn section.
1834   this->rela_dyn_section(layout);
1835
1836   return this->got_;
1837 }
1838
1839 // Reserve a GOT entry for a local symbol, and regenerate any
1840 // necessary dynamic relocations.
1841
1842 template<int size>
1843 void
1844 Target_x86_64<size>::reserve_local_got_entry(
1845     unsigned int got_index,
1846     Sized_relobj<size, false>* obj,
1847     unsigned int r_sym,
1848     unsigned int got_type)
1849 {
1850   unsigned int got_offset = got_index * 8;
1851   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1852
1853   this->got_->reserve_local(got_index, obj, r_sym, got_type);
1854   switch (got_type)
1855     {
1856     case GOT_TYPE_STANDARD:
1857       if (parameters->options().output_is_position_independent())
1858         rela_dyn->add_local_relative(obj, r_sym, elfcpp::R_X86_64_RELATIVE,
1859                                      this->got_, got_offset, 0, false);
1860       break;
1861     case GOT_TYPE_TLS_OFFSET:
1862       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_TPOFF64,
1863                           this->got_, got_offset, 0);
1864       break;
1865     case GOT_TYPE_TLS_PAIR:
1866       this->got_->reserve_slot(got_index + 1);
1867       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_DTPMOD64,
1868                           this->got_, got_offset, 0);
1869       break;
1870     case GOT_TYPE_TLS_DESC:
1871       gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
1872       // this->got_->reserve_slot(got_index + 1);
1873       // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
1874       //                               this->got_, got_offset, 0);
1875       break;
1876     default:
1877       gold_unreachable();
1878     }
1879 }
1880
1881 // Reserve a GOT entry for a global symbol, and regenerate any
1882 // necessary dynamic relocations.
1883
1884 template<int size>
1885 void
1886 Target_x86_64<size>::reserve_global_got_entry(unsigned int got_index,
1887                                               Symbol* gsym,
1888                                               unsigned int got_type)
1889 {
1890   unsigned int got_offset = got_index * 8;
1891   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1892
1893   this->got_->reserve_global(got_index, gsym, got_type);
1894   switch (got_type)
1895     {
1896     case GOT_TYPE_STANDARD:
1897       if (!gsym->final_value_is_known())
1898         {
1899           if (gsym->is_from_dynobj()
1900               || gsym->is_undefined()
1901               || gsym->is_preemptible()
1902               || gsym->type() == elfcpp::STT_GNU_IFUNC)
1903             rela_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT,
1904                                  this->got_, got_offset, 0);
1905           else
1906             rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
1907                                           this->got_, got_offset, 0, false);
1908         }
1909       break;
1910     case GOT_TYPE_TLS_OFFSET:
1911       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TPOFF64,
1912                                     this->got_, got_offset, 0, false);
1913       break;
1914     case GOT_TYPE_TLS_PAIR:
1915       this->got_->reserve_slot(got_index + 1);
1916       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPMOD64,
1917                                     this->got_, got_offset, 0, false);
1918       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPOFF64,
1919                                     this->got_, got_offset + 8, 0, false);
1920       break;
1921     case GOT_TYPE_TLS_DESC:
1922       this->got_->reserve_slot(got_index + 1);
1923       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TLSDESC,
1924                                     this->got_, got_offset, 0, false);
1925       break;
1926     default:
1927       gold_unreachable();
1928     }
1929 }
1930
1931 // Register an existing PLT entry for a global symbol.
1932
1933 template<int size>
1934 void
1935 Target_x86_64<size>::register_global_plt_entry(Symbol_table* symtab,
1936                                                Layout* layout,
1937                                                unsigned int plt_index,
1938                                                Symbol* gsym)
1939 {
1940   gold_assert(this->plt_ != NULL);
1941   gold_assert(!gsym->has_plt_offset());
1942
1943   this->plt_->reserve_slot(plt_index);
1944
1945   gsym->set_plt_offset((plt_index + 1) * this->plt_entry_size());
1946
1947   unsigned int got_offset = (plt_index + 3) * 8;
1948   this->plt_->add_relocation(symtab, layout, gsym, got_offset);
1949 }
1950
1951 // Force a COPY relocation for a given symbol.
1952
1953 template<int size>
1954 void
1955 Target_x86_64<size>::emit_copy_reloc(
1956     Symbol_table* symtab, Symbol* sym, Output_section* os, off_t offset)
1957 {
1958   this->copy_relocs_.emit_copy_reloc(symtab,
1959                                      symtab->get_sized_symbol<size>(sym),
1960                                      os,
1961                                      offset,
1962                                      this->rela_dyn_section(NULL));
1963 }
1964
1965 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1966
1967 template<int size>
1968 void
1969 Target_x86_64<size>::define_tls_base_symbol(Symbol_table* symtab,
1970                                             Layout* layout)
1971 {
1972   if (this->tls_base_symbol_defined_)
1973     return;
1974
1975   Output_segment* tls_segment = layout->tls_segment();
1976   if (tls_segment != NULL)
1977     {
1978       bool is_exec = parameters->options().output_is_executable();
1979       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1980                                        Symbol_table::PREDEFINED,
1981                                        tls_segment, 0, 0,
1982                                        elfcpp::STT_TLS,
1983                                        elfcpp::STB_LOCAL,
1984                                        elfcpp::STV_HIDDEN, 0,
1985                                        (is_exec
1986                                         ? Symbol::SEGMENT_END
1987                                         : Symbol::SEGMENT_START),
1988                                        true);
1989     }
1990   this->tls_base_symbol_defined_ = true;
1991 }
1992
1993 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1994
1995 template<int size>
1996 void
1997 Target_x86_64<size>::reserve_tlsdesc_entries(Symbol_table* symtab,
1998                                              Layout* layout)
1999 {
2000   if (this->plt_ == NULL)
2001     this->make_plt_section(symtab, layout);
2002
2003   if (!this->plt_->has_tlsdesc_entry())
2004     {
2005       // Allocate the TLSDESC_GOT entry.
2006       Output_data_got<64, false>* got = this->got_section(symtab, layout);
2007       unsigned int got_offset = got->add_constant(0);
2008
2009       // Allocate the TLSDESC_PLT entry.
2010       this->plt_->reserve_tlsdesc_entry(got_offset);
2011     }
2012 }
2013
2014 // Create a GOT entry for the TLS module index.
2015
2016 template<int size>
2017 unsigned int
2018 Target_x86_64<size>::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2019                                          Sized_relobj_file<size, false>* object)
2020 {
2021   if (this->got_mod_index_offset_ == -1U)
2022     {
2023       gold_assert(symtab != NULL && layout != NULL && object != NULL);
2024       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
2025       Output_data_got<64, false>* got = this->got_section(symtab, layout);
2026       unsigned int got_offset = got->add_constant(0);
2027       rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
2028                           got_offset, 0);
2029       got->add_constant(0);
2030       this->got_mod_index_offset_ = got_offset;
2031     }
2032   return this->got_mod_index_offset_;
2033 }
2034
2035 // Optimize the TLS relocation type based on what we know about the
2036 // symbol.  IS_FINAL is true if the final address of this symbol is
2037 // known at link time.
2038
2039 template<int size>
2040 tls::Tls_optimization
2041 Target_x86_64<size>::optimize_tls_reloc(bool is_final, int r_type)
2042 {
2043   // If we are generating a shared library, then we can't do anything
2044   // in the linker.
2045   if (parameters->options().shared())
2046     return tls::TLSOPT_NONE;
2047
2048   switch (r_type)
2049     {
2050     case elfcpp::R_X86_64_TLSGD:
2051     case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2052     case elfcpp::R_X86_64_TLSDESC_CALL:
2053       // These are General-Dynamic which permits fully general TLS
2054       // access.  Since we know that we are generating an executable,
2055       // we can convert this to Initial-Exec.  If we also know that
2056       // this is a local symbol, we can further switch to Local-Exec.
2057       if (is_final)
2058         return tls::TLSOPT_TO_LE;
2059       return tls::TLSOPT_TO_IE;
2060
2061     case elfcpp::R_X86_64_TLSLD:
2062       // This is Local-Dynamic, which refers to a local symbol in the
2063       // dynamic TLS block.  Since we know that we generating an
2064       // executable, we can switch to Local-Exec.
2065       return tls::TLSOPT_TO_LE;
2066
2067     case elfcpp::R_X86_64_DTPOFF32:
2068     case elfcpp::R_X86_64_DTPOFF64:
2069       // Another Local-Dynamic reloc.
2070       return tls::TLSOPT_TO_LE;
2071
2072     case elfcpp::R_X86_64_GOTTPOFF:
2073       // These are Initial-Exec relocs which get the thread offset
2074       // from the GOT.  If we know that we are linking against the
2075       // local symbol, we can switch to Local-Exec, which links the
2076       // thread offset into the instruction.
2077       if (is_final)
2078         return tls::TLSOPT_TO_LE;
2079       return tls::TLSOPT_NONE;
2080
2081     case elfcpp::R_X86_64_TPOFF32:
2082       // When we already have Local-Exec, there is nothing further we
2083       // can do.
2084       return tls::TLSOPT_NONE;
2085
2086     default:
2087       gold_unreachable();
2088     }
2089 }
2090
2091 // Get the Reference_flags for a particular relocation.
2092
2093 template<int size>
2094 int
2095 Target_x86_64<size>::Scan::get_reference_flags(unsigned int r_type)
2096 {
2097   switch (r_type)
2098     {
2099     case elfcpp::R_X86_64_NONE:
2100     case elfcpp::R_X86_64_GNU_VTINHERIT:
2101     case elfcpp::R_X86_64_GNU_VTENTRY:
2102     case elfcpp::R_X86_64_GOTPC32:
2103     case elfcpp::R_X86_64_GOTPC64:
2104       // No symbol reference.
2105       return 0;
2106
2107     case elfcpp::R_X86_64_64:
2108     case elfcpp::R_X86_64_32:
2109     case elfcpp::R_X86_64_32S:
2110     case elfcpp::R_X86_64_16:
2111     case elfcpp::R_X86_64_8:
2112       return Symbol::ABSOLUTE_REF;
2113
2114     case elfcpp::R_X86_64_PC64:
2115     case elfcpp::R_X86_64_PC32:
2116     case elfcpp::R_X86_64_PC32_BND:
2117     case elfcpp::R_X86_64_PC16:
2118     case elfcpp::R_X86_64_PC8:
2119     case elfcpp::R_X86_64_GOTOFF64:
2120       return Symbol::RELATIVE_REF;
2121
2122     case elfcpp::R_X86_64_PLT32:
2123     case elfcpp::R_X86_64_PLT32_BND:
2124     case elfcpp::R_X86_64_PLTOFF64:
2125       return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
2126
2127     case elfcpp::R_X86_64_GOT64:
2128     case elfcpp::R_X86_64_GOT32:
2129     case elfcpp::R_X86_64_GOTPCREL64:
2130     case elfcpp::R_X86_64_GOTPCREL:
2131     case elfcpp::R_X86_64_GOTPLT64:
2132       // Absolute in GOT.
2133       return Symbol::ABSOLUTE_REF;
2134
2135     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2136     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2137     case elfcpp::R_X86_64_TLSDESC_CALL:
2138     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2139     case elfcpp::R_X86_64_DTPOFF32:
2140     case elfcpp::R_X86_64_DTPOFF64:
2141     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2142     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2143       return Symbol::TLS_REF;
2144
2145     case elfcpp::R_X86_64_COPY:
2146     case elfcpp::R_X86_64_GLOB_DAT:
2147     case elfcpp::R_X86_64_JUMP_SLOT:
2148     case elfcpp::R_X86_64_RELATIVE:
2149     case elfcpp::R_X86_64_IRELATIVE:
2150     case elfcpp::R_X86_64_TPOFF64:
2151     case elfcpp::R_X86_64_DTPMOD64:
2152     case elfcpp::R_X86_64_TLSDESC:
2153     case elfcpp::R_X86_64_SIZE32:
2154     case elfcpp::R_X86_64_SIZE64:
2155     default:
2156       // Not expected.  We will give an error later.
2157       return 0;
2158     }
2159 }
2160
2161 // Report an unsupported relocation against a local symbol.
2162
2163 template<int size>
2164 void
2165 Target_x86_64<size>::Scan::unsupported_reloc_local(
2166      Sized_relobj_file<size, false>* object,
2167      unsigned int r_type)
2168 {
2169   gold_error(_("%s: unsupported reloc %u against local symbol"),
2170              object->name().c_str(), r_type);
2171 }
2172
2173 // We are about to emit a dynamic relocation of type R_TYPE.  If the
2174 // dynamic linker does not support it, issue an error.  The GNU linker
2175 // only issues a non-PIC error for an allocated read-only section.
2176 // Here we know the section is allocated, but we don't know that it is
2177 // read-only.  But we check for all the relocation types which the
2178 // glibc dynamic linker supports, so it seems appropriate to issue an
2179 // error even if the section is not read-only.  If GSYM is not NULL,
2180 // it is the symbol the relocation is against; if it is NULL, the
2181 // relocation is against a local symbol.
2182
2183 template<int size>
2184 void
2185 Target_x86_64<size>::Scan::check_non_pic(Relobj* object, unsigned int r_type,
2186                                          Symbol* gsym)
2187 {
2188   switch (r_type)
2189     {
2190       // These are the relocation types supported by glibc for x86_64
2191       // which should always work.
2192     case elfcpp::R_X86_64_RELATIVE:
2193     case elfcpp::R_X86_64_IRELATIVE:
2194     case elfcpp::R_X86_64_GLOB_DAT:
2195     case elfcpp::R_X86_64_JUMP_SLOT:
2196     case elfcpp::R_X86_64_DTPMOD64:
2197     case elfcpp::R_X86_64_DTPOFF64:
2198     case elfcpp::R_X86_64_TPOFF64:
2199     case elfcpp::R_X86_64_64:
2200     case elfcpp::R_X86_64_COPY:
2201       return;
2202
2203       // glibc supports these reloc types, but they can overflow.
2204     case elfcpp::R_X86_64_PC32:
2205     case elfcpp::R_X86_64_PC32_BND:
2206       // A PC relative reference is OK against a local symbol or if
2207       // the symbol is defined locally.
2208       if (gsym == NULL
2209           || (!gsym->is_from_dynobj()
2210               && !gsym->is_undefined()
2211               && !gsym->is_preemptible()))
2212         return;
2213       /* Fall through.  */
2214     case elfcpp::R_X86_64_32:
2215       // R_X86_64_32 is OK for x32.
2216       if (size == 32 && r_type == elfcpp::R_X86_64_32)
2217         return;
2218       if (this->issued_non_pic_error_)
2219         return;
2220       gold_assert(parameters->options().output_is_position_independent());
2221       if (gsym == NULL)
2222         object->error(_("requires dynamic R_X86_64_32 reloc which may "
2223                         "overflow at runtime; recompile with -fPIC"));
2224       else
2225         {
2226           const char *r_name;
2227           switch (r_type)
2228             {
2229             case elfcpp::R_X86_64_32:
2230               r_name = "R_X86_64_32";
2231               break;
2232             case elfcpp::R_X86_64_PC32:
2233               r_name = "R_X86_64_PC32";
2234               break;
2235             case elfcpp::R_X86_64_PC32_BND:
2236               r_name = "R_X86_64_PC32_BND";
2237               break;
2238             default:
2239               gold_unreachable();
2240               break;
2241             }
2242           object->error(_("requires dynamic %s reloc against '%s' "
2243                           "which may overflow at runtime; recompile "
2244                           "with -fPIC"),
2245                         r_name, gsym->name());
2246         }
2247       this->issued_non_pic_error_ = true;
2248       return;
2249
2250     default:
2251       // This prevents us from issuing more than one error per reloc
2252       // section.  But we can still wind up issuing more than one
2253       // error per object file.
2254       if (this->issued_non_pic_error_)
2255         return;
2256       gold_assert(parameters->options().output_is_position_independent());
2257       object->error(_("requires unsupported dynamic reloc %u; "
2258                       "recompile with -fPIC"),
2259                     r_type);
2260       this->issued_non_pic_error_ = true;
2261       return;
2262
2263     case elfcpp::R_X86_64_NONE:
2264       gold_unreachable();
2265     }
2266 }
2267
2268 // Return whether we need to make a PLT entry for a relocation of the
2269 // given type against a STT_GNU_IFUNC symbol.
2270
2271 template<int size>
2272 bool
2273 Target_x86_64<size>::Scan::reloc_needs_plt_for_ifunc(
2274      Sized_relobj_file<size, false>* object,
2275      unsigned int r_type)
2276 {
2277   int flags = Scan::get_reference_flags(r_type);
2278   if (flags & Symbol::TLS_REF)
2279     gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2280                object->name().c_str(), r_type);
2281   return flags != 0;
2282 }
2283
2284 // Scan a relocation for a local symbol.
2285
2286 template<int size>
2287 inline void
2288 Target_x86_64<size>::Scan::local(Symbol_table* symtab,
2289                                  Layout* layout,
2290                                  Target_x86_64<size>* target,
2291                                  Sized_relobj_file<size, false>* object,
2292                                  unsigned int data_shndx,
2293                                  Output_section* output_section,
2294                                  const elfcpp::Rela<size, false>& reloc,
2295                                  unsigned int r_type,
2296                                  const elfcpp::Sym<size, false>& lsym,
2297                                  bool is_discarded)
2298 {
2299   if (is_discarded)
2300     return;
2301
2302   // A local STT_GNU_IFUNC symbol may require a PLT entry.
2303   bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
2304   if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
2305     {
2306       unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2307       target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
2308     }
2309
2310   switch (r_type)
2311     {
2312     case elfcpp::R_X86_64_NONE:
2313     case elfcpp::R_X86_64_GNU_VTINHERIT:
2314     case elfcpp::R_X86_64_GNU_VTENTRY:
2315       break;
2316
2317     case elfcpp::R_X86_64_64:
2318       // If building a shared library (or a position-independent
2319       // executable), we need to create a dynamic relocation for this
2320       // location.  The relocation applied at link time will apply the
2321       // link-time value, so we flag the location with an
2322       // R_X86_64_RELATIVE relocation so the dynamic loader can
2323       // relocate it easily.
2324       if (parameters->options().output_is_position_independent())
2325         {
2326           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2327           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2328           rela_dyn->add_local_relative(object, r_sym,
2329                                        (size == 32
2330                                         ? elfcpp::R_X86_64_RELATIVE64
2331                                         : elfcpp::R_X86_64_RELATIVE),
2332                                        output_section, data_shndx,
2333                                        reloc.get_r_offset(),
2334                                        reloc.get_r_addend(), is_ifunc);
2335         }
2336       break;
2337
2338     case elfcpp::R_X86_64_32:
2339     case elfcpp::R_X86_64_32S:
2340     case elfcpp::R_X86_64_16:
2341     case elfcpp::R_X86_64_8:
2342       // If building a shared library (or a position-independent
2343       // executable), we need to create a dynamic relocation for this
2344       // location.  We can't use an R_X86_64_RELATIVE relocation
2345       // because that is always a 64-bit relocation.
2346       if (parameters->options().output_is_position_independent())
2347         {
2348           // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
2349           if (size == 32 && r_type == elfcpp::R_X86_64_32)
2350             {
2351               unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2352               Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2353               rela_dyn->add_local_relative(object, r_sym,
2354                                            elfcpp::R_X86_64_RELATIVE,
2355                                            output_section, data_shndx,
2356                                            reloc.get_r_offset(),
2357                                            reloc.get_r_addend(), is_ifunc);
2358               break;
2359             }
2360
2361           this->check_non_pic(object, r_type, NULL);
2362
2363           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2364           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2365           if (lsym.get_st_type() != elfcpp::STT_SECTION)
2366             rela_dyn->add_local(object, r_sym, r_type, output_section,
2367                                 data_shndx, reloc.get_r_offset(),
2368                                 reloc.get_r_addend());
2369           else
2370             {
2371               gold_assert(lsym.get_st_value() == 0);
2372               unsigned int shndx = lsym.get_st_shndx();
2373               bool is_ordinary;
2374               shndx = object->adjust_sym_shndx(r_sym, shndx,
2375                                                &is_ordinary);
2376               if (!is_ordinary)
2377                 object->error(_("section symbol %u has bad shndx %u"),
2378                               r_sym, shndx);
2379               else
2380                 rela_dyn->add_local_section(object, shndx,
2381                                             r_type, output_section,
2382                                             data_shndx, reloc.get_r_offset(),
2383                                             reloc.get_r_addend());
2384             }
2385         }
2386       break;
2387
2388     case elfcpp::R_X86_64_PC64:
2389     case elfcpp::R_X86_64_PC32:
2390     case elfcpp::R_X86_64_PC32_BND:
2391     case elfcpp::R_X86_64_PC16:
2392     case elfcpp::R_X86_64_PC8:
2393       break;
2394
2395     case elfcpp::R_X86_64_PLT32:
2396     case elfcpp::R_X86_64_PLT32_BND:
2397       // Since we know this is a local symbol, we can handle this as a
2398       // PC32 reloc.
2399       break;
2400
2401     case elfcpp::R_X86_64_GOTPC32:
2402     case elfcpp::R_X86_64_GOTOFF64:
2403     case elfcpp::R_X86_64_GOTPC64:
2404     case elfcpp::R_X86_64_PLTOFF64:
2405       // We need a GOT section.
2406       target->got_section(symtab, layout);
2407       // For PLTOFF64, we'd normally want a PLT section, but since we
2408       // know this is a local symbol, no PLT is needed.
2409       break;
2410
2411     case elfcpp::R_X86_64_GOT64:
2412     case elfcpp::R_X86_64_GOT32:
2413     case elfcpp::R_X86_64_GOTPCREL64:
2414     case elfcpp::R_X86_64_GOTPCREL:
2415     case elfcpp::R_X86_64_GOTPLT64:
2416       {
2417         // The symbol requires a GOT entry.
2418         Output_data_got<64, false>* got = target->got_section(symtab, layout);
2419         unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2420
2421         // For a STT_GNU_IFUNC symbol we want the PLT offset.  That
2422         // lets function pointers compare correctly with shared
2423         // libraries.  Otherwise we would need an IRELATIVE reloc.
2424         bool is_new;
2425         if (is_ifunc)
2426           is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
2427         else
2428           is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
2429         if (is_new)
2430           {
2431             // If we are generating a shared object, we need to add a
2432             // dynamic relocation for this symbol's GOT entry.
2433             if (parameters->options().output_is_position_independent())
2434               {
2435                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2436                 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2437                 if (r_type != elfcpp::R_X86_64_GOT32)
2438                   {
2439                     unsigned int got_offset =
2440                       object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
2441                     rela_dyn->add_local_relative(object, r_sym,
2442                                                  elfcpp::R_X86_64_RELATIVE,
2443                                                  got, got_offset, 0, is_ifunc);
2444                   }
2445                 else
2446                   {
2447                     this->check_non_pic(object, r_type, NULL);
2448
2449                     gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2450                     rela_dyn->add_local(
2451                         object, r_sym, r_type, got,
2452                         object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
2453                   }
2454               }
2455           }
2456         // For GOTPLT64, we'd normally want a PLT section, but since
2457         // we know this is a local symbol, no PLT is needed.
2458       }
2459       break;
2460
2461     case elfcpp::R_X86_64_COPY:
2462     case elfcpp::R_X86_64_GLOB_DAT:
2463     case elfcpp::R_X86_64_JUMP_SLOT:
2464     case elfcpp::R_X86_64_RELATIVE:
2465     case elfcpp::R_X86_64_IRELATIVE:
2466       // These are outstanding tls relocs, which are unexpected when linking
2467     case elfcpp::R_X86_64_TPOFF64:
2468     case elfcpp::R_X86_64_DTPMOD64:
2469     case elfcpp::R_X86_64_TLSDESC:
2470       gold_error(_("%s: unexpected reloc %u in object file"),
2471                  object->name().c_str(), r_type);
2472       break;
2473
2474       // These are initial tls relocs, which are expected when linking
2475     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2476     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2477     case elfcpp::R_X86_64_TLSDESC_CALL:
2478     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2479     case elfcpp::R_X86_64_DTPOFF32:
2480     case elfcpp::R_X86_64_DTPOFF64:
2481     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2482     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2483       {
2484         bool output_is_shared = parameters->options().shared();
2485         const tls::Tls_optimization optimized_type
2486             = Target_x86_64<size>::optimize_tls_reloc(!output_is_shared,
2487                                                       r_type);
2488         switch (r_type)
2489           {
2490           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
2491             if (optimized_type == tls::TLSOPT_NONE)
2492               {
2493                 // Create a pair of GOT entries for the module index and
2494                 // dtv-relative offset.
2495                 Output_data_got<64, false>* got
2496                     = target->got_section(symtab, layout);
2497                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2498                 unsigned int shndx = lsym.get_st_shndx();
2499                 bool is_ordinary;
2500                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
2501                 if (!is_ordinary)
2502                   object->error(_("local symbol %u has bad shndx %u"),
2503                               r_sym, shndx);
2504                 else
2505                   got->add_local_pair_with_rel(object, r_sym,
2506                                                shndx,
2507                                                GOT_TYPE_TLS_PAIR,
2508                                                target->rela_dyn_section(layout),
2509                                                elfcpp::R_X86_64_DTPMOD64);
2510               }
2511             else if (optimized_type != tls::TLSOPT_TO_LE)
2512               unsupported_reloc_local(object, r_type);
2513             break;
2514
2515           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2516             target->define_tls_base_symbol(symtab, layout);
2517             if (optimized_type == tls::TLSOPT_NONE)
2518               {
2519                 // Create reserved PLT and GOT entries for the resolver.
2520                 target->reserve_tlsdesc_entries(symtab, layout);
2521
2522                 // Generate a double GOT entry with an
2523                 // R_X86_64_TLSDESC reloc.  The R_X86_64_TLSDESC reloc
2524                 // is resolved lazily, so the GOT entry needs to be in
2525                 // an area in .got.plt, not .got.  Call got_section to
2526                 // make sure the section has been created.
2527                 target->got_section(symtab, layout);
2528                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2529                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2530                 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
2531                   {
2532                     unsigned int got_offset = got->add_constant(0);
2533                     got->add_constant(0);
2534                     object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
2535                                                  got_offset);
2536                     Reloc_section* rt = target->rela_tlsdesc_section(layout);
2537                     // We store the arguments we need in a vector, and
2538                     // use the index into the vector as the parameter
2539                     // to pass to the target specific routines.
2540                     uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
2541                     void* arg = reinterpret_cast<void*>(intarg);
2542                     rt->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
2543                                             got, got_offset, 0);
2544                   }
2545               }
2546             else if (optimized_type != tls::TLSOPT_TO_LE)
2547               unsupported_reloc_local(object, r_type);
2548             break;
2549
2550           case elfcpp::R_X86_64_TLSDESC_CALL:
2551             break;
2552
2553           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
2554             if (optimized_type == tls::TLSOPT_NONE)
2555               {
2556                 // Create a GOT entry for the module index.
2557                 target->got_mod_index_entry(symtab, layout, object);
2558               }
2559             else if (optimized_type != tls::TLSOPT_TO_LE)
2560               unsupported_reloc_local(object, r_type);
2561             break;
2562
2563           case elfcpp::R_X86_64_DTPOFF32:
2564           case elfcpp::R_X86_64_DTPOFF64:
2565             break;
2566
2567           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
2568             layout->set_has_static_tls();
2569             if (optimized_type == tls::TLSOPT_NONE)
2570               {
2571                 // Create a GOT entry for the tp-relative offset.
2572                 Output_data_got<64, false>* got
2573                     = target->got_section(symtab, layout);
2574                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2575                 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
2576                                         target->rela_dyn_section(layout),
2577                                         elfcpp::R_X86_64_TPOFF64);
2578               }
2579             else if (optimized_type != tls::TLSOPT_TO_LE)
2580               unsupported_reloc_local(object, r_type);
2581             break;
2582
2583           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
2584             layout->set_has_static_tls();
2585             if (output_is_shared)
2586               unsupported_reloc_local(object, r_type);
2587             break;
2588
2589           default:
2590             gold_unreachable();
2591           }
2592       }
2593       break;
2594
2595     case elfcpp::R_X86_64_SIZE32:
2596     case elfcpp::R_X86_64_SIZE64:
2597     default:
2598       gold_error(_("%s: unsupported reloc %u against local symbol"),
2599                  object->name().c_str(), r_type);
2600       break;
2601     }
2602 }
2603
2604
2605 // Report an unsupported relocation against a global symbol.
2606
2607 template<int size>
2608 void
2609 Target_x86_64<size>::Scan::unsupported_reloc_global(
2610     Sized_relobj_file<size, false>* object,
2611     unsigned int r_type,
2612     Symbol* gsym)
2613 {
2614   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2615              object->name().c_str(), r_type, gsym->demangled_name().c_str());
2616 }
2617
2618 // Returns true if this relocation type could be that of a function pointer.
2619 template<int size>
2620 inline bool
2621 Target_x86_64<size>::Scan::possible_function_pointer_reloc(unsigned int r_type)
2622 {
2623   switch (r_type)
2624     {
2625     case elfcpp::R_X86_64_64:
2626     case elfcpp::R_X86_64_32:
2627     case elfcpp::R_X86_64_32S:
2628     case elfcpp::R_X86_64_16:
2629     case elfcpp::R_X86_64_8:
2630     case elfcpp::R_X86_64_GOT64:
2631     case elfcpp::R_X86_64_GOT32:
2632     case elfcpp::R_X86_64_GOTPCREL64:
2633     case elfcpp::R_X86_64_GOTPCREL:
2634     case elfcpp::R_X86_64_GOTPLT64:
2635       {
2636         return true;
2637       }
2638     }
2639   return false;
2640 }
2641
2642 // For safe ICF, scan a relocation for a local 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::local_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   const elfcpp::Sym<size, false>&)
2658 {
2659   // When building a shared library, do not fold any local symbols as it is
2660   // not possible to distinguish pointer taken versus a call by looking at
2661   // the relocation types.
2662   return (parameters->options().shared()
2663           || possible_function_pointer_reloc(r_type));
2664 }
2665
2666 // For safe ICF, scan a relocation for a global symbol to check if it
2667 // corresponds to a function pointer being taken.  In that case mark
2668 // the function whose pointer was taken as not foldable.
2669
2670 template<int size>
2671 inline bool
2672 Target_x86_64<size>::Scan::global_reloc_may_be_function_pointer(
2673   Symbol_table*,
2674   Layout* ,
2675   Target_x86_64<size>* ,
2676   Sized_relobj_file<size, false>* ,
2677   unsigned int ,
2678   Output_section* ,
2679   const elfcpp::Rela<size, false>& ,
2680   unsigned int r_type,
2681   Symbol* gsym)
2682 {
2683   // When building a shared library, do not fold symbols whose visibility
2684   // is hidden, internal or protected.
2685   return ((parameters->options().shared()
2686            && (gsym->visibility() == elfcpp::STV_INTERNAL
2687                || gsym->visibility() == elfcpp::STV_PROTECTED
2688                || gsym->visibility() == elfcpp::STV_HIDDEN))
2689           || possible_function_pointer_reloc(r_type));
2690 }
2691
2692 // Scan a relocation for a global symbol.
2693
2694 template<int size>
2695 inline void
2696 Target_x86_64<size>::Scan::global(Symbol_table* symtab,
2697                             Layout* layout,
2698                             Target_x86_64<size>* target,
2699                             Sized_relobj_file<size, false>* object,
2700                             unsigned int data_shndx,
2701                             Output_section* output_section,
2702                             const elfcpp::Rela<size, false>& reloc,
2703                             unsigned int r_type,
2704                             Symbol* gsym)
2705 {
2706   // A STT_GNU_IFUNC symbol may require a PLT entry.
2707   if (gsym->type() == elfcpp::STT_GNU_IFUNC
2708       && this->reloc_needs_plt_for_ifunc(object, r_type))
2709     target->make_plt_entry(symtab, layout, gsym);
2710
2711   switch (r_type)
2712     {
2713     case elfcpp::R_X86_64_NONE:
2714     case elfcpp::R_X86_64_GNU_VTINHERIT:
2715     case elfcpp::R_X86_64_GNU_VTENTRY:
2716       break;
2717
2718     case elfcpp::R_X86_64_64:
2719     case elfcpp::R_X86_64_32:
2720     case elfcpp::R_X86_64_32S:
2721     case elfcpp::R_X86_64_16:
2722     case elfcpp::R_X86_64_8:
2723       {
2724         // Make a PLT entry if necessary.
2725         if (gsym->needs_plt_entry())
2726           {
2727             target->make_plt_entry(symtab, layout, gsym);
2728             // Since this is not a PC-relative relocation, we may be
2729             // taking the address of a function. In that case we need to
2730             // set the entry in the dynamic symbol table to the address of
2731             // the PLT entry.
2732             if (gsym->is_from_dynobj() && !parameters->options().shared())
2733               gsym->set_needs_dynsym_value();
2734           }
2735         // Make a dynamic relocation if necessary.
2736         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2737           {
2738             if (gsym->may_need_copy_reloc())
2739               {
2740                 target->copy_reloc(symtab, layout, object,
2741                                    data_shndx, output_section, gsym, reloc);
2742               }
2743             else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2744                       || (size == 32 && r_type == elfcpp::R_X86_64_32))
2745                      && gsym->type() == elfcpp::STT_GNU_IFUNC
2746                      && gsym->can_use_relative_reloc(false)
2747                      && !gsym->is_from_dynobj()
2748                      && !gsym->is_undefined()
2749                      && !gsym->is_preemptible())
2750               {
2751                 // Use an IRELATIVE reloc for a locally defined
2752                 // STT_GNU_IFUNC symbol.  This makes a function
2753                 // address in a PIE executable match the address in a
2754                 // shared library that it links against.
2755                 Reloc_section* rela_dyn =
2756                   target->rela_irelative_section(layout);
2757                 unsigned int r_type = elfcpp::R_X86_64_IRELATIVE;
2758                 rela_dyn->add_symbolless_global_addend(gsym, r_type,
2759                                                        output_section, object,
2760                                                        data_shndx,
2761                                                        reloc.get_r_offset(),
2762                                                        reloc.get_r_addend());
2763               }
2764             else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2765                       || (size == 32 && r_type == elfcpp::R_X86_64_32))
2766                      && gsym->can_use_relative_reloc(false))
2767               {
2768                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2769                 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
2770                                               output_section, object,
2771                                               data_shndx,
2772                                               reloc.get_r_offset(),
2773                                               reloc.get_r_addend(), false);
2774               }
2775             else
2776               {
2777                 this->check_non_pic(object, r_type, gsym);
2778                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2779                 rela_dyn->add_global(gsym, r_type, output_section, object,
2780                                      data_shndx, reloc.get_r_offset(),
2781                                      reloc.get_r_addend());
2782               }
2783           }
2784       }
2785       break;
2786
2787     case elfcpp::R_X86_64_PC64:
2788     case elfcpp::R_X86_64_PC32:
2789     case elfcpp::R_X86_64_PC32_BND:
2790     case elfcpp::R_X86_64_PC16:
2791     case elfcpp::R_X86_64_PC8:
2792       {
2793         // Make a PLT entry if necessary.
2794         if (gsym->needs_plt_entry())
2795           target->make_plt_entry(symtab, layout, gsym);
2796         // Make a dynamic relocation if necessary.
2797         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2798           {
2799             if (gsym->may_need_copy_reloc())
2800               {
2801                 target->copy_reloc(symtab, layout, object,
2802                                    data_shndx, output_section, gsym, reloc);
2803               }
2804             else
2805               {
2806                 this->check_non_pic(object, r_type, gsym);
2807                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2808                 rela_dyn->add_global(gsym, r_type, output_section, object,
2809                                      data_shndx, reloc.get_r_offset(),
2810                                      reloc.get_r_addend());
2811               }
2812           }
2813       }
2814       break;
2815
2816     case elfcpp::R_X86_64_GOT64:
2817     case elfcpp::R_X86_64_GOT32:
2818     case elfcpp::R_X86_64_GOTPCREL64:
2819     case elfcpp::R_X86_64_GOTPCREL:
2820     case elfcpp::R_X86_64_GOTPLT64:
2821       {
2822         // The symbol requires a GOT entry.
2823         Output_data_got<64, false>* got = target->got_section(symtab, layout);
2824         if (gsym->final_value_is_known())
2825           {
2826             // For a STT_GNU_IFUNC symbol we want the PLT address.
2827             if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2828               got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2829             else
2830               got->add_global(gsym, GOT_TYPE_STANDARD);
2831           }
2832         else
2833           {
2834             // If this symbol is not fully resolved, we need to add a
2835             // dynamic relocation for it.
2836             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2837
2838             // Use a GLOB_DAT rather than a RELATIVE reloc if:
2839             //
2840             // 1) The symbol may be defined in some other module.
2841             //
2842             // 2) We are building a shared library and this is a
2843             // protected symbol; using GLOB_DAT means that the dynamic
2844             // linker can use the address of the PLT in the main
2845             // executable when appropriate so that function address
2846             // comparisons work.
2847             //
2848             // 3) This is a STT_GNU_IFUNC symbol in position dependent
2849             // code, again so that function address comparisons work.
2850             if (gsym->is_from_dynobj()
2851                 || gsym->is_undefined()
2852                 || gsym->is_preemptible()
2853                 || (gsym->visibility() == elfcpp::STV_PROTECTED
2854                     && parameters->options().shared())
2855                 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2856                     && parameters->options().output_is_position_independent()))
2857               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, rela_dyn,
2858                                        elfcpp::R_X86_64_GLOB_DAT);
2859             else
2860               {
2861                 // For a STT_GNU_IFUNC symbol we want to write the PLT
2862                 // offset into the GOT, so that function pointer
2863                 // comparisons work correctly.
2864                 bool is_new;
2865                 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2866                   is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2867                 else
2868                   {
2869                     is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2870                     // Tell the dynamic linker to use the PLT address
2871                     // when resolving relocations.
2872                     if (gsym->is_from_dynobj()
2873                         && !parameters->options().shared())
2874                       gsym->set_needs_dynsym_value();
2875                   }
2876                 if (is_new)
2877                   {
2878                     unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2879                     rela_dyn->add_global_relative(gsym,
2880                                                   elfcpp::R_X86_64_RELATIVE,
2881                                                   got, got_off, 0, false);
2882                   }
2883               }
2884           }
2885         // For GOTPLT64, we also need a PLT entry (but only if the
2886         // symbol is not fully resolved).
2887         if (r_type == elfcpp::R_X86_64_GOTPLT64
2888             && !gsym->final_value_is_known())
2889           target->make_plt_entry(symtab, layout, gsym);
2890       }
2891       break;
2892
2893     case elfcpp::R_X86_64_PLT32:
2894     case elfcpp::R_X86_64_PLT32_BND:
2895       // If the symbol is fully resolved, this is just a PC32 reloc.
2896       // Otherwise we need a PLT entry.
2897       if (gsym->final_value_is_known())
2898         break;
2899       // If building a shared library, we can also skip the PLT entry
2900       // if the symbol is defined in the output file and is protected
2901       // or hidden.
2902       if (gsym->is_defined()
2903           && !gsym->is_from_dynobj()
2904           && !gsym->is_preemptible())
2905         break;
2906       target->make_plt_entry(symtab, layout, gsym);
2907       break;
2908
2909     case elfcpp::R_X86_64_GOTPC32:
2910     case elfcpp::R_X86_64_GOTOFF64:
2911     case elfcpp::R_X86_64_GOTPC64:
2912     case elfcpp::R_X86_64_PLTOFF64:
2913       // We need a GOT section.
2914       target->got_section(symtab, layout);
2915       // For PLTOFF64, we also need a PLT entry (but only if the
2916       // symbol is not fully resolved).
2917       if (r_type == elfcpp::R_X86_64_PLTOFF64
2918           && !gsym->final_value_is_known())
2919         target->make_plt_entry(symtab, layout, gsym);
2920       break;
2921
2922     case elfcpp::R_X86_64_COPY:
2923     case elfcpp::R_X86_64_GLOB_DAT:
2924     case elfcpp::R_X86_64_JUMP_SLOT:
2925     case elfcpp::R_X86_64_RELATIVE:
2926     case elfcpp::R_X86_64_IRELATIVE:
2927       // These are outstanding tls relocs, which are unexpected when linking
2928     case elfcpp::R_X86_64_TPOFF64:
2929     case elfcpp::R_X86_64_DTPMOD64:
2930     case elfcpp::R_X86_64_TLSDESC:
2931       gold_error(_("%s: unexpected reloc %u in object file"),
2932                  object->name().c_str(), r_type);
2933       break;
2934
2935       // These are initial tls relocs, which are expected for global()
2936     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2937     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2938     case elfcpp::R_X86_64_TLSDESC_CALL:
2939     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2940     case elfcpp::R_X86_64_DTPOFF32:
2941     case elfcpp::R_X86_64_DTPOFF64:
2942     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2943     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2944       {
2945         const bool is_final = gsym->final_value_is_known();
2946         const tls::Tls_optimization optimized_type
2947             = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
2948         switch (r_type)
2949           {
2950           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
2951             if (optimized_type == tls::TLSOPT_NONE)
2952               {
2953                 // Create a pair of GOT entries for the module index and
2954                 // dtv-relative offset.
2955                 Output_data_got<64, false>* got
2956                     = target->got_section(symtab, layout);
2957                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2958                                               target->rela_dyn_section(layout),
2959                                               elfcpp::R_X86_64_DTPMOD64,
2960                                               elfcpp::R_X86_64_DTPOFF64);
2961               }
2962             else if (optimized_type == tls::TLSOPT_TO_IE)
2963               {
2964                 // Create a GOT entry for the tp-relative offset.
2965                 Output_data_got<64, false>* got
2966                     = target->got_section(symtab, layout);
2967                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2968                                          target->rela_dyn_section(layout),
2969                                          elfcpp::R_X86_64_TPOFF64);
2970               }
2971             else if (optimized_type != tls::TLSOPT_TO_LE)
2972               unsupported_reloc_global(object, r_type, gsym);
2973             break;
2974
2975           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2976             target->define_tls_base_symbol(symtab, layout);
2977             if (optimized_type == tls::TLSOPT_NONE)
2978               {
2979                 // Create reserved PLT and GOT entries for the resolver.
2980                 target->reserve_tlsdesc_entries(symtab, layout);
2981
2982                 // Create a double GOT entry with an R_X86_64_TLSDESC
2983                 // reloc.  The R_X86_64_TLSDESC reloc is resolved
2984                 // lazily, so the GOT entry needs to be in an area in
2985                 // .got.plt, not .got.  Call got_section to make sure
2986                 // the section has been created.
2987                 target->got_section(symtab, layout);
2988                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2989                 Reloc_section* rt = target->rela_tlsdesc_section(layout);
2990                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2991                                               elfcpp::R_X86_64_TLSDESC, 0);
2992               }
2993             else if (optimized_type == tls::TLSOPT_TO_IE)
2994               {
2995                 // Create a GOT entry for the tp-relative offset.
2996                 Output_data_got<64, false>* got
2997                     = target->got_section(symtab, layout);
2998                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2999                                          target->rela_dyn_section(layout),
3000                                          elfcpp::R_X86_64_TPOFF64);
3001               }
3002             else if (optimized_type != tls::TLSOPT_TO_LE)
3003               unsupported_reloc_global(object, r_type, gsym);
3004             break;
3005
3006           case elfcpp::R_X86_64_TLSDESC_CALL:
3007             break;
3008
3009           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
3010             if (optimized_type == tls::TLSOPT_NONE)
3011               {
3012                 // Create a GOT entry for the module index.
3013                 target->got_mod_index_entry(symtab, layout, object);
3014               }
3015             else if (optimized_type != tls::TLSOPT_TO_LE)
3016               unsupported_reloc_global(object, r_type, gsym);
3017             break;
3018
3019           case elfcpp::R_X86_64_DTPOFF32:
3020           case elfcpp::R_X86_64_DTPOFF64:
3021             break;
3022
3023           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
3024             layout->set_has_static_tls();
3025             if (optimized_type == tls::TLSOPT_NONE)
3026               {
3027                 // Create a GOT entry for the tp-relative offset.
3028                 Output_data_got<64, false>* got
3029                     = target->got_section(symtab, layout);
3030                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
3031                                          target->rela_dyn_section(layout),
3032                                          elfcpp::R_X86_64_TPOFF64);
3033               }
3034             else if (optimized_type != tls::TLSOPT_TO_LE)
3035               unsupported_reloc_global(object, r_type, gsym);
3036             break;
3037
3038           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
3039             layout->set_has_static_tls();
3040             if (parameters->options().shared())
3041               unsupported_reloc_global(object, r_type, gsym);
3042             break;
3043
3044           default:
3045             gold_unreachable();
3046           }
3047       }
3048       break;
3049
3050     case elfcpp::R_X86_64_SIZE32:
3051     case elfcpp::R_X86_64_SIZE64:
3052     default:
3053       gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3054                  object->name().c_str(), r_type,
3055                  gsym->demangled_name().c_str());
3056       break;
3057     }
3058 }
3059
3060 template<int size>
3061 void
3062 Target_x86_64<size>::gc_process_relocs(Symbol_table* symtab,
3063                                        Layout* layout,
3064                                        Sized_relobj_file<size, false>* object,
3065                                        unsigned int data_shndx,
3066                                        unsigned int sh_type,
3067                                        const unsigned char* prelocs,
3068                                        size_t reloc_count,
3069                                        Output_section* output_section,
3070                                        bool needs_special_offset_handling,
3071                                        size_t local_symbol_count,
3072                                        const unsigned char* plocal_symbols)
3073 {
3074
3075   if (sh_type == elfcpp::SHT_REL)
3076     {
3077       return;
3078     }
3079
3080    gold::gc_process_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3081                            typename Target_x86_64<size>::Scan,
3082                            typename Target_x86_64<size>::Relocatable_size_for_reloc>(
3083     symtab,
3084     layout,
3085     this,
3086     object,
3087     data_shndx,
3088     prelocs,
3089     reloc_count,
3090     output_section,
3091     needs_special_offset_handling,
3092     local_symbol_count,
3093     plocal_symbols);
3094
3095 }
3096 // Scan relocations for a section.
3097
3098 template<int size>
3099 void
3100 Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
3101                                  Layout* layout,
3102                                  Sized_relobj_file<size, false>* object,
3103                                  unsigned int data_shndx,
3104                                  unsigned int sh_type,
3105                                  const unsigned char* prelocs,
3106                                  size_t reloc_count,
3107                                  Output_section* output_section,
3108                                  bool needs_special_offset_handling,
3109                                  size_t local_symbol_count,
3110                                  const unsigned char* plocal_symbols)
3111 {
3112   if (sh_type == elfcpp::SHT_REL)
3113     {
3114       gold_error(_("%s: unsupported REL reloc section"),
3115                  object->name().c_str());
3116       return;
3117     }
3118
3119   gold::scan_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3120       typename Target_x86_64<size>::Scan>(
3121     symtab,
3122     layout,
3123     this,
3124     object,
3125     data_shndx,
3126     prelocs,
3127     reloc_count,
3128     output_section,
3129     needs_special_offset_handling,
3130     local_symbol_count,
3131     plocal_symbols);
3132 }
3133
3134 // Finalize the sections.
3135
3136 template<int size>
3137 void
3138 Target_x86_64<size>::do_finalize_sections(
3139     Layout* layout,
3140     const Input_objects*,
3141     Symbol_table* symtab)
3142 {
3143   const Reloc_section* rel_plt = (this->plt_ == NULL
3144                                   ? NULL
3145                                   : this->plt_->rela_plt());
3146   layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
3147                                   this->rela_dyn_, true, false);
3148
3149   // Fill in some more dynamic tags.
3150   Output_data_dynamic* const odyn = layout->dynamic_data();
3151   if (odyn != NULL)
3152     {
3153       if (this->plt_ != NULL
3154           && this->plt_->output_section() != NULL
3155           && this->plt_->has_tlsdesc_entry())
3156         {
3157           unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
3158           unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
3159           this->got_->finalize_data_size();
3160           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
3161                                         this->plt_, plt_offset);
3162           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
3163                                         this->got_, got_offset);
3164         }
3165     }
3166
3167   // Emit any relocs we saved in an attempt to avoid generating COPY
3168   // relocs.
3169   if (this->copy_relocs_.any_saved_relocs())
3170     this->copy_relocs_.emit(this->rela_dyn_section(layout));
3171
3172   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
3173   // the .got.plt section.
3174   Symbol* sym = this->global_offset_table_;
3175   if (sym != NULL)
3176     {
3177       uint64_t data_size = this->got_plt_->current_data_size();
3178       symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
3179     }
3180
3181   if (parameters->doing_static_link()
3182       && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
3183     {
3184       // If linking statically, make sure that the __rela_iplt symbols
3185       // were defined if necessary, even if we didn't create a PLT.
3186       static const Define_symbol_in_segment syms[] =
3187         {
3188           {
3189             "__rela_iplt_start",        // name
3190             elfcpp::PT_LOAD,            // segment_type
3191             elfcpp::PF_W,               // segment_flags_set
3192             elfcpp::PF(0),              // segment_flags_clear
3193             0,                          // value
3194             0,                          // size
3195             elfcpp::STT_NOTYPE,         // type
3196             elfcpp::STB_GLOBAL,         // binding
3197             elfcpp::STV_HIDDEN,         // visibility
3198             0,                          // nonvis
3199             Symbol::SEGMENT_START,      // offset_from_base
3200             true                        // only_if_ref
3201           },
3202           {
3203             "__rela_iplt_end",          // name
3204             elfcpp::PT_LOAD,            // segment_type
3205             elfcpp::PF_W,               // segment_flags_set
3206             elfcpp::PF(0),              // segment_flags_clear
3207             0,                          // value
3208             0,                          // size
3209             elfcpp::STT_NOTYPE,         // type
3210             elfcpp::STB_GLOBAL,         // binding
3211             elfcpp::STV_HIDDEN,         // visibility
3212             0,                          // nonvis
3213             Symbol::SEGMENT_START,      // offset_from_base
3214             true                        // only_if_ref
3215           }
3216         };
3217
3218       symtab->define_symbols(layout, 2, syms,
3219                              layout->script_options()->saw_sections_clause());
3220     }
3221 }
3222
3223 // Perform a relocation.
3224
3225 template<int size>
3226 inline bool
3227 Target_x86_64<size>::Relocate::relocate(
3228     const Relocate_info<size, false>* relinfo,
3229     Target_x86_64<size>* target,
3230     Output_section*,
3231     size_t relnum,
3232     const elfcpp::Rela<size, false>& rela,
3233     unsigned int r_type,
3234     const Sized_symbol<size>* gsym,
3235     const Symbol_value<size>* psymval,
3236     unsigned char* view,
3237     typename elfcpp::Elf_types<size>::Elf_Addr address,
3238     section_size_type view_size)
3239 {
3240   if (this->skip_call_tls_get_addr_)
3241     {
3242       if ((r_type != elfcpp::R_X86_64_PLT32
3243            && r_type != elfcpp::R_X86_64_PLT32_BND
3244            && r_type != elfcpp::R_X86_64_PC32_BND
3245            && r_type != elfcpp::R_X86_64_PC32)
3246           || gsym == NULL
3247           || strcmp(gsym->name(), "__tls_get_addr") != 0)
3248         {
3249           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3250                                  _("missing expected TLS relocation"));
3251         }
3252       else
3253         {
3254           this->skip_call_tls_get_addr_ = false;
3255           return false;
3256         }
3257     }
3258
3259   if (view == NULL)
3260     return true;
3261
3262   const Sized_relobj_file<size, false>* object = relinfo->object;
3263
3264   // Pick the value to use for symbols defined in the PLT.
3265   Symbol_value<size> symval;
3266   if (gsym != NULL
3267       && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
3268     {
3269       symval.set_output_value(target->plt_address_for_global(gsym));
3270       psymval = &symval;
3271     }
3272   else if (gsym == NULL && psymval->is_ifunc_symbol())
3273     {
3274       unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3275       if (object->local_has_plt_offset(r_sym))
3276         {
3277           symval.set_output_value(target->plt_address_for_local(object, r_sym));
3278           psymval = &symval;
3279         }
3280     }
3281
3282   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3283
3284   // Get the GOT offset if needed.
3285   // The GOT pointer points to the end of the GOT section.
3286   // We need to subtract the size of the GOT section to get
3287   // the actual offset to use in the relocation.
3288   bool have_got_offset = false;
3289   unsigned int got_offset = 0;
3290   switch (r_type)
3291     {
3292     case elfcpp::R_X86_64_GOT32:
3293     case elfcpp::R_X86_64_GOT64:
3294     case elfcpp::R_X86_64_GOTPLT64:
3295     case elfcpp::R_X86_64_GOTPCREL:
3296     case elfcpp::R_X86_64_GOTPCREL64:
3297       if (gsym != NULL)
3298         {
3299           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
3300           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
3301         }
3302       else
3303         {
3304           unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3305           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
3306           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
3307                         - target->got_size());
3308         }
3309       have_got_offset = true;
3310       break;
3311
3312     default:
3313       break;
3314     }
3315
3316   switch (r_type)
3317     {
3318     case elfcpp::R_X86_64_NONE:
3319     case elfcpp::R_X86_64_GNU_VTINHERIT:
3320     case elfcpp::R_X86_64_GNU_VTENTRY:
3321       break;
3322
3323     case elfcpp::R_X86_64_64:
3324       Relocate_functions<size, false>::rela64(view, object, psymval, addend);
3325       break;
3326
3327     case elfcpp::R_X86_64_PC64:
3328       Relocate_functions<size, false>::pcrela64(view, object, psymval, addend,
3329                                               address);
3330       break;
3331
3332     case elfcpp::R_X86_64_32:
3333       // FIXME: we need to verify that value + addend fits into 32 bits:
3334       //    uint64_t x = value + addend;
3335       //    x == static_cast<uint64_t>(static_cast<uint32_t>(x))
3336       // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
3337       Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3338       break;
3339
3340     case elfcpp::R_X86_64_32S:
3341       // FIXME: we need to verify that value + addend fits into 32 bits:
3342       //    int64_t x = value + addend;   // note this quantity is signed!
3343       //    x == static_cast<int64_t>(static_cast<int32_t>(x))
3344       Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3345       break;
3346
3347     case elfcpp::R_X86_64_PC32:
3348     case elfcpp::R_X86_64_PC32_BND:
3349       Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3350                                                 address);
3351       break;
3352
3353     case elfcpp::R_X86_64_16:
3354       Relocate_functions<size, false>::rela16(view, object, psymval, addend);
3355       break;
3356
3357     case elfcpp::R_X86_64_PC16:
3358       Relocate_functions<size, false>::pcrela16(view, object, psymval, addend,
3359                                                 address);
3360       break;
3361
3362     case elfcpp::R_X86_64_8:
3363       Relocate_functions<size, false>::rela8(view, object, psymval, addend);
3364       break;
3365
3366     case elfcpp::R_X86_64_PC8:
3367       Relocate_functions<size, false>::pcrela8(view, object, psymval, addend,
3368                                                address);
3369       break;
3370
3371     case elfcpp::R_X86_64_PLT32:
3372     case elfcpp::R_X86_64_PLT32_BND:
3373       gold_assert(gsym == NULL
3374                   || gsym->has_plt_offset()
3375                   || gsym->final_value_is_known()
3376                   || (gsym->is_defined()
3377                       && !gsym->is_from_dynobj()
3378                       && !gsym->is_preemptible()));
3379       // Note: while this code looks the same as for R_X86_64_PC32, it
3380       // behaves differently because psymval was set to point to
3381       // the PLT entry, rather than the symbol, in Scan::global().
3382       Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3383                                                 address);
3384       break;
3385
3386     case elfcpp::R_X86_64_PLTOFF64:
3387       {
3388         gold_assert(gsym);
3389         gold_assert(gsym->has_plt_offset()
3390                     || gsym->final_value_is_known());
3391         typename elfcpp::Elf_types<size>::Elf_Addr got_address;
3392         got_address = target->got_section(NULL, NULL)->address();
3393         Relocate_functions<size, false>::rela64(view, object, psymval,
3394                                                 addend - got_address);
3395       }
3396
3397     case elfcpp::R_X86_64_GOT32:
3398       gold_assert(have_got_offset);
3399       Relocate_functions<size, false>::rela32(view, got_offset, addend);
3400       break;
3401
3402     case elfcpp::R_X86_64_GOTPC32:
3403       {
3404         gold_assert(gsym);
3405         typename elfcpp::Elf_types<size>::Elf_Addr value;
3406         value = target->got_plt_section()->address();
3407         Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3408       }
3409       break;
3410
3411     case elfcpp::R_X86_64_GOT64:
3412       // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
3413       // Since we always add a PLT entry, this is equivalent.
3414     case elfcpp::R_X86_64_GOTPLT64:
3415       gold_assert(have_got_offset);
3416       Relocate_functions<size, false>::rela64(view, got_offset, addend);
3417       break;
3418
3419     case elfcpp::R_X86_64_GOTPC64:
3420       {
3421         gold_assert(gsym);
3422         typename elfcpp::Elf_types<size>::Elf_Addr value;
3423         value = target->got_plt_section()->address();
3424         Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3425       }
3426       break;
3427
3428     case elfcpp::R_X86_64_GOTOFF64:
3429       {
3430         typename elfcpp::Elf_types<size>::Elf_Addr value;
3431         value = (psymval->value(object, 0)
3432                  - target->got_plt_section()->address());
3433         Relocate_functions<size, false>::rela64(view, value, addend);
3434       }
3435       break;
3436
3437     case elfcpp::R_X86_64_GOTPCREL:
3438       {
3439         gold_assert(have_got_offset);
3440         typename elfcpp::Elf_types<size>::Elf_Addr value;
3441         value = target->got_plt_section()->address() + got_offset;
3442         Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3443       }
3444       break;
3445
3446     case elfcpp::R_X86_64_GOTPCREL64:
3447       {
3448         gold_assert(have_got_offset);
3449         typename elfcpp::Elf_types<size>::Elf_Addr value;
3450         value = target->got_plt_section()->address() + got_offset;
3451         Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3452       }
3453       break;
3454
3455     case elfcpp::R_X86_64_COPY:
3456     case elfcpp::R_X86_64_GLOB_DAT:
3457     case elfcpp::R_X86_64_JUMP_SLOT:
3458     case elfcpp::R_X86_64_RELATIVE:
3459     case elfcpp::R_X86_64_IRELATIVE:
3460       // These are outstanding tls relocs, which are unexpected when linking
3461     case elfcpp::R_X86_64_TPOFF64:
3462     case elfcpp::R_X86_64_DTPMOD64:
3463     case elfcpp::R_X86_64_TLSDESC:
3464       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3465                              _("unexpected reloc %u in object file"),
3466                              r_type);
3467       break;
3468
3469       // These are initial tls relocs, which are expected when linking
3470     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3471     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3472     case elfcpp::R_X86_64_TLSDESC_CALL:
3473     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3474     case elfcpp::R_X86_64_DTPOFF32:
3475     case elfcpp::R_X86_64_DTPOFF64:
3476     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3477     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3478       this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
3479                          view, address, view_size);
3480       break;
3481
3482     case elfcpp::R_X86_64_SIZE32:
3483     case elfcpp::R_X86_64_SIZE64:
3484     default:
3485       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3486                              _("unsupported reloc %u"),
3487                              r_type);
3488       break;
3489     }
3490
3491   return true;
3492 }
3493
3494 // Perform a TLS relocation.
3495
3496 template<int size>
3497 inline void
3498 Target_x86_64<size>::Relocate::relocate_tls(
3499     const Relocate_info<size, false>* relinfo,
3500     Target_x86_64<size>* target,
3501     size_t relnum,
3502     const elfcpp::Rela<size, false>& rela,
3503     unsigned int r_type,
3504     const Sized_symbol<size>* gsym,
3505     const Symbol_value<size>* psymval,
3506     unsigned char* view,
3507     typename elfcpp::Elf_types<size>::Elf_Addr address,
3508     section_size_type view_size)
3509 {
3510   Output_segment* tls_segment = relinfo->layout->tls_segment();
3511
3512   const Sized_relobj_file<size, false>* object = relinfo->object;
3513   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3514   elfcpp::Shdr<size, false> data_shdr(relinfo->data_shdr);
3515   bool is_executable = (data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0;
3516
3517   typename elfcpp::Elf_types<size>::Elf_Addr value = psymval->value(relinfo->object, 0);
3518
3519   const bool is_final = (gsym == NULL
3520                          ? !parameters->options().shared()
3521                          : gsym->final_value_is_known());
3522   tls::Tls_optimization optimized_type
3523       = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
3524   switch (r_type)
3525     {
3526     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3527       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3528         {
3529           // If this code sequence is used in a non-executable section,
3530           // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3531           // on the assumption that it's being used by itself in a debug
3532           // section.  Therefore, in the unlikely event that the code
3533           // sequence appears in a non-executable section, we simply
3534           // leave it unoptimized.
3535           optimized_type = tls::TLSOPT_NONE;
3536         }
3537       if (optimized_type == tls::TLSOPT_TO_LE)
3538         {
3539           if (tls_segment == NULL)
3540             {
3541               gold_assert(parameters->errors()->error_count() > 0
3542                           || issue_undefined_symbol_error(gsym));
3543               return;
3544             }
3545           this->tls_gd_to_le(relinfo, relnum, tls_segment,
3546                              rela, r_type, value, view,
3547                              view_size);
3548           break;
3549         }
3550       else
3551         {
3552           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3553                                    ? GOT_TYPE_TLS_OFFSET
3554                                    : GOT_TYPE_TLS_PAIR);
3555           unsigned int got_offset;
3556           if (gsym != NULL)
3557             {
3558               gold_assert(gsym->has_got_offset(got_type));
3559               got_offset = gsym->got_offset(got_type) - target->got_size();
3560             }
3561           else
3562             {
3563               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3564               gold_assert(object->local_has_got_offset(r_sym, got_type));
3565               got_offset = (object->local_got_offset(r_sym, got_type)
3566                             - target->got_size());
3567             }
3568           if (optimized_type == tls::TLSOPT_TO_IE)
3569             {
3570               value = target->got_plt_section()->address() + got_offset;
3571               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rela, r_type,
3572                                  value, view, address, view_size);
3573               break;
3574             }
3575           else if (optimized_type == tls::TLSOPT_NONE)
3576             {
3577               // Relocate the field with the offset of the pair of GOT
3578               // entries.
3579               value = target->got_plt_section()->address() + got_offset;
3580               Relocate_functions<size, false>::pcrela32(view, value, addend,
3581                                                         address);
3582               break;
3583             }
3584         }
3585       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3586                              _("unsupported reloc %u"), r_type);
3587       break;
3588
3589     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3590     case elfcpp::R_X86_64_TLSDESC_CALL:
3591       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3592         {
3593           // See above comment for R_X86_64_TLSGD.
3594           optimized_type = tls::TLSOPT_NONE;
3595         }
3596       if (optimized_type == tls::TLSOPT_TO_LE)
3597         {
3598           if (tls_segment == NULL)
3599             {
3600               gold_assert(parameters->errors()->error_count() > 0
3601                           || issue_undefined_symbol_error(gsym));
3602               return;
3603             }
3604           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3605                                   rela, r_type, value, view,
3606                                   view_size);
3607           break;
3608         }
3609       else
3610         {
3611           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3612                                    ? GOT_TYPE_TLS_OFFSET
3613                                    : GOT_TYPE_TLS_DESC);
3614           unsigned int got_offset = 0;
3615           if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC
3616               && optimized_type == tls::TLSOPT_NONE)
3617             {
3618               // We created GOT entries in the .got.tlsdesc portion of
3619               // the .got.plt section, but the offset stored in the
3620               // symbol is the offset within .got.tlsdesc.
3621               got_offset = (target->got_size()
3622                             + target->got_plt_section()->data_size());
3623             }
3624           if (gsym != NULL)
3625             {
3626               gold_assert(gsym->has_got_offset(got_type));
3627               got_offset += gsym->got_offset(got_type) - target->got_size();
3628             }
3629           else
3630             {
3631               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3632               gold_assert(object->local_has_got_offset(r_sym, got_type));
3633               got_offset += (object->local_got_offset(r_sym, got_type)
3634                              - target->got_size());
3635             }
3636           if (optimized_type == tls::TLSOPT_TO_IE)
3637             {
3638               if (tls_segment == NULL)
3639                 {
3640                   gold_assert(parameters->errors()->error_count() > 0
3641                               || issue_undefined_symbol_error(gsym));
3642                   return;
3643                 }
3644               value = target->got_plt_section()->address() + got_offset;
3645               this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment,
3646                                       rela, r_type, value, view, address,
3647                                       view_size);
3648               break;
3649             }
3650           else if (optimized_type == tls::TLSOPT_NONE)
3651             {
3652               if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3653                 {
3654                   // Relocate the field with the offset of the pair of GOT
3655                   // entries.
3656                   value = target->got_plt_section()->address() + got_offset;
3657                   Relocate_functions<size, false>::pcrela32(view, value, addend,
3658                                                             address);
3659                 }
3660               break;
3661             }
3662         }
3663       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3664                              _("unsupported reloc %u"), r_type);
3665       break;
3666
3667     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3668       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3669         {
3670           // See above comment for R_X86_64_TLSGD.
3671           optimized_type = tls::TLSOPT_NONE;
3672         }
3673       if (optimized_type == tls::TLSOPT_TO_LE)
3674         {
3675           if (tls_segment == NULL)
3676             {
3677               gold_assert(parameters->errors()->error_count() > 0
3678                           || issue_undefined_symbol_error(gsym));
3679               return;
3680             }
3681           this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
3682                              value, view, view_size);
3683           break;
3684         }
3685       else if (optimized_type == tls::TLSOPT_NONE)
3686         {
3687           // Relocate the field with the offset of the GOT entry for
3688           // the module index.
3689           unsigned int got_offset;
3690           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3691                         - target->got_size());
3692           value = target->got_plt_section()->address() + got_offset;
3693           Relocate_functions<size, false>::pcrela32(view, value, addend,
3694                                                     address);
3695           break;
3696         }
3697       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3698                              _("unsupported reloc %u"), r_type);
3699       break;
3700
3701     case elfcpp::R_X86_64_DTPOFF32:
3702       // This relocation type is used in debugging information.
3703       // In that case we need to not optimize the value.  If the
3704       // section is not executable, then we assume we should not
3705       // optimize this reloc.  See comments above for R_X86_64_TLSGD,
3706       // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
3707       // R_X86_64_TLSLD.
3708       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3709         {
3710           if (tls_segment == NULL)
3711             {
3712               gold_assert(parameters->errors()->error_count() > 0
3713                           || issue_undefined_symbol_error(gsym));
3714               return;
3715             }
3716           value -= tls_segment->memsz();
3717         }
3718       Relocate_functions<size, false>::rela32(view, value, addend);
3719       break;
3720
3721     case elfcpp::R_X86_64_DTPOFF64:
3722       // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
3723       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3724         {
3725           if (tls_segment == NULL)
3726             {
3727               gold_assert(parameters->errors()->error_count() > 0
3728                           || issue_undefined_symbol_error(gsym));
3729               return;
3730             }
3731           value -= tls_segment->memsz();
3732         }
3733       Relocate_functions<size, false>::rela64(view, value, addend);
3734       break;
3735
3736     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3737       if (optimized_type == tls::TLSOPT_TO_LE)
3738         {
3739           if (tls_segment == NULL)
3740             {
3741               gold_assert(parameters->errors()->error_count() > 0
3742                           || issue_undefined_symbol_error(gsym));
3743               return;
3744             }
3745           Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
3746                                                       tls_segment, rela,
3747                                                       r_type, value, view,
3748                                                       view_size);
3749           break;
3750         }
3751       else if (optimized_type == tls::TLSOPT_NONE)
3752         {
3753           // Relocate the field with the offset of the GOT entry for
3754           // the tp-relative offset of the symbol.
3755           unsigned int got_offset;
3756           if (gsym != NULL)
3757             {
3758               gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
3759               got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
3760                             - target->got_size());
3761             }
3762           else
3763             {
3764               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3765               gold_assert(object->local_has_got_offset(r_sym,
3766                                                        GOT_TYPE_TLS_OFFSET));
3767               got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
3768                             - target->got_size());
3769             }
3770           value = target->got_plt_section()->address() + got_offset;
3771           Relocate_functions<size, false>::pcrela32(view, value, addend,
3772                                                     address);
3773           break;
3774         }
3775       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3776                              _("unsupported reloc type %u"),
3777                              r_type);
3778       break;
3779
3780     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3781       if (tls_segment == NULL)
3782         {
3783           gold_assert(parameters->errors()->error_count() > 0
3784                       || issue_undefined_symbol_error(gsym));
3785           return;
3786         }
3787       value -= tls_segment->memsz();
3788       Relocate_functions<size, false>::rela32(view, value, addend);
3789       break;
3790     }
3791 }
3792
3793 // Do a relocation in which we convert a TLS General-Dynamic to an
3794 // Initial-Exec.
3795
3796 template<int size>
3797 inline void
3798 Target_x86_64<size>::Relocate::tls_gd_to_ie(
3799     const Relocate_info<size, false>* relinfo,
3800     size_t relnum,
3801     Output_segment*,
3802     const elfcpp::Rela<size, false>& rela,
3803     unsigned int,
3804     typename elfcpp::Elf_types<size>::Elf_Addr value,
3805     unsigned char* view,
3806     typename elfcpp::Elf_types<size>::Elf_Addr address,
3807     section_size_type view_size)
3808 {
3809   // For SIZE == 64:
3810   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3811   //    .word 0x6666; rex64; call __tls_get_addr
3812   //    ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
3813   // For SIZE == 32:
3814   //    leaq foo@tlsgd(%rip),%rdi;
3815   //    .word 0x6666; rex64; call __tls_get_addr
3816   //    ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
3817
3818   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3819   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3820                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3821
3822   if (size == 64)
3823     {
3824       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3825                        -4);
3826       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3827                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3828       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3829              16);
3830     }
3831   else
3832     {
3833       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3834                        -3);
3835       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3836                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3837       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3838              15);
3839     }
3840
3841   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3842   Relocate_functions<size, false>::pcrela32(view + 8, value, addend - 8,
3843                                             address);
3844
3845   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3846   // We can skip it.
3847   this->skip_call_tls_get_addr_ = true;
3848 }
3849
3850 // Do a relocation in which we convert a TLS General-Dynamic to a
3851 // Local-Exec.
3852
3853 template<int size>
3854 inline void
3855 Target_x86_64<size>::Relocate::tls_gd_to_le(
3856     const Relocate_info<size, false>* relinfo,
3857     size_t relnum,
3858     Output_segment* tls_segment,
3859     const elfcpp::Rela<size, false>& rela,
3860     unsigned int,
3861     typename elfcpp::Elf_types<size>::Elf_Addr value,
3862     unsigned char* view,
3863     section_size_type view_size)
3864 {
3865   // For SIZE == 64:
3866   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3867   //    .word 0x6666; rex64; call __tls_get_addr
3868   //    ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
3869   // For SIZE == 32:
3870   //    leaq foo@tlsgd(%rip),%rdi;
3871   //    .word 0x6666; rex64; call __tls_get_addr
3872   //    ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
3873
3874   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3875   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3876                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3877
3878   if (size == 64)
3879     {
3880       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3881                        -4);
3882       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3883                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3884       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3885              16);
3886     }
3887   else
3888     {
3889       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3890                        -3);
3891       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3892                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3893
3894       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3895              15);
3896     }
3897
3898   value -= tls_segment->memsz();
3899   Relocate_functions<size, false>::rela32(view + 8, value, 0);
3900
3901   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3902   // We can skip it.
3903   this->skip_call_tls_get_addr_ = true;
3904 }
3905
3906 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
3907
3908 template<int size>
3909 inline void
3910 Target_x86_64<size>::Relocate::tls_desc_gd_to_ie(
3911     const Relocate_info<size, false>* relinfo,
3912     size_t relnum,
3913     Output_segment*,
3914     const elfcpp::Rela<size, false>& rela,
3915     unsigned int r_type,
3916     typename elfcpp::Elf_types<size>::Elf_Addr value,
3917     unsigned char* view,
3918     typename elfcpp::Elf_types<size>::Elf_Addr address,
3919     section_size_type view_size)
3920 {
3921   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3922     {
3923       // leaq foo@tlsdesc(%rip), %rax
3924       // ==> movq foo@gottpoff(%rip), %rax
3925       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3926       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3927       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3928                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3929       view[-2] = 0x8b;
3930       const elfcpp::Elf_Xword addend = rela.get_r_addend();
3931       Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3932     }
3933   else
3934     {
3935       // call *foo@tlscall(%rax)
3936       // ==> nop; nop
3937       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3938       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3939       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3940                      view[0] == 0xff && view[1] == 0x10);
3941       view[0] = 0x66;
3942       view[1] = 0x90;
3943     }
3944 }
3945
3946 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
3947
3948 template<int size>
3949 inline void
3950 Target_x86_64<size>::Relocate::tls_desc_gd_to_le(
3951     const Relocate_info<size, false>* relinfo,
3952     size_t relnum,
3953     Output_segment* tls_segment,
3954     const elfcpp::Rela<size, false>& rela,
3955     unsigned int r_type,
3956     typename elfcpp::Elf_types<size>::Elf_Addr value,
3957     unsigned char* view,
3958     section_size_type view_size)
3959 {
3960   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3961     {
3962       // leaq foo@tlsdesc(%rip), %rax
3963       // ==> movq foo@tpoff, %rax
3964       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3965       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3966       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3967                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3968       view[-2] = 0xc7;
3969       view[-1] = 0xc0;
3970       value -= tls_segment->memsz();
3971       Relocate_functions<size, false>::rela32(view, value, 0);
3972     }
3973   else
3974     {
3975       // call *foo@tlscall(%rax)
3976       // ==> nop; nop
3977       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3978       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3979       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3980                      view[0] == 0xff && view[1] == 0x10);
3981       view[0] = 0x66;
3982       view[1] = 0x90;
3983     }
3984 }
3985
3986 template<int size>
3987 inline void
3988 Target_x86_64<size>::Relocate::tls_ld_to_le(
3989     const Relocate_info<size, false>* relinfo,
3990     size_t relnum,
3991     Output_segment*,
3992     const elfcpp::Rela<size, false>& rela,
3993     unsigned int,
3994     typename elfcpp::Elf_types<size>::Elf_Addr,
3995     unsigned char* view,
3996     section_size_type view_size)
3997 {
3998   // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
3999   // For SIZE == 64:
4000   // ... leq foo@dtpoff(%rax),%reg
4001   // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
4002   // For SIZE == 32:
4003   // ... leq foo@dtpoff(%rax),%reg
4004   // ==> nopl 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
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, 9);
4008
4009   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4010                  view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
4011
4012   tls::check_tls(relinfo, relnum, rela.get_r_offset(), view[4] == 0xe8);
4013
4014   if (size == 64)
4015     memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
4016   else
4017     memcpy(view - 3, "\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0", 12);
4018
4019   // The next reloc should be a PLT32 reloc against __tls_get_addr.
4020   // We can skip it.
4021   this->skip_call_tls_get_addr_ = true;
4022 }
4023
4024 // Do a relocation in which we convert a TLS Initial-Exec to a
4025 // Local-Exec.
4026
4027 template<int size>
4028 inline void
4029 Target_x86_64<size>::Relocate::tls_ie_to_le(
4030     const Relocate_info<size, false>* relinfo,
4031     size_t relnum,
4032     Output_segment* tls_segment,
4033     const elfcpp::Rela<size, false>& rela,
4034     unsigned int,
4035     typename elfcpp::Elf_types<size>::Elf_Addr value,
4036     unsigned char* view,
4037     section_size_type view_size)
4038 {
4039   // We need to examine the opcodes to figure out which instruction we
4040   // are looking at.
4041
4042   // movq foo@gottpoff(%rip),%reg  ==>  movq $YY,%reg
4043   // addq foo@gottpoff(%rip),%reg  ==>  addq $YY,%reg
4044
4045   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4046   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
4047
4048   unsigned char op1 = view[-3];
4049   unsigned char op2 = view[-2];
4050   unsigned char op3 = view[-1];
4051   unsigned char reg = op3 >> 3;
4052
4053   if (op2 == 0x8b)
4054     {
4055       // movq
4056       if (op1 == 0x4c)
4057         view[-3] = 0x49;
4058       view[-2] = 0xc7;
4059       view[-1] = 0xc0 | reg;
4060     }
4061   else if (reg == 4)
4062     {
4063       // Special handling for %rsp.
4064       if (op1 == 0x4c)
4065         view[-3] = 0x49;
4066       view[-2] = 0x81;
4067       view[-1] = 0xc0 | reg;
4068     }
4069   else
4070     {
4071       // addq
4072       if (op1 == 0x4c)
4073         view[-3] = 0x4d;
4074       view[-2] = 0x8d;
4075       view[-1] = 0x80 | reg | (reg << 3);
4076     }
4077
4078   value -= tls_segment->memsz();
4079   Relocate_functions<size, false>::rela32(view, value, 0);
4080 }
4081
4082 // Relocate section data.
4083
4084 template<int size>
4085 void
4086 Target_x86_64<size>::relocate_section(
4087     const Relocate_info<size, false>* relinfo,
4088     unsigned int sh_type,
4089     const unsigned char* prelocs,
4090     size_t reloc_count,
4091     Output_section* output_section,
4092     bool needs_special_offset_handling,
4093     unsigned char* view,
4094     typename elfcpp::Elf_types<size>::Elf_Addr address,
4095     section_size_type view_size,
4096     const Reloc_symbol_changes* reloc_symbol_changes)
4097 {
4098   gold_assert(sh_type == elfcpp::SHT_RELA);
4099
4100   gold::relocate_section<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
4101                          typename Target_x86_64<size>::Relocate,
4102                          gold::Default_comdat_behavior>(
4103     relinfo,
4104     this,
4105     prelocs,
4106     reloc_count,
4107     output_section,
4108     needs_special_offset_handling,
4109     view,
4110     address,
4111     view_size,
4112     reloc_symbol_changes);
4113 }
4114
4115 // Apply an incremental relocation.  Incremental relocations always refer
4116 // to global symbols.
4117
4118 template<int size>
4119 void
4120 Target_x86_64<size>::apply_relocation(
4121     const Relocate_info<size, false>* relinfo,
4122     typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
4123     unsigned int r_type,
4124     typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
4125     const Symbol* gsym,
4126     unsigned char* view,
4127     typename elfcpp::Elf_types<size>::Elf_Addr address,
4128     section_size_type view_size)
4129 {
4130   gold::apply_relocation<size, false, Target_x86_64<size>,
4131                          typename Target_x86_64<size>::Relocate>(
4132     relinfo,
4133     this,
4134     r_offset,
4135     r_type,
4136     r_addend,
4137     gsym,
4138     view,
4139     address,
4140     view_size);
4141 }
4142
4143 // Return the size of a relocation while scanning during a relocatable
4144 // link.
4145
4146 template<int size>
4147 unsigned int
4148 Target_x86_64<size>::Relocatable_size_for_reloc::get_size_for_reloc(
4149     unsigned int r_type,
4150     Relobj* object)
4151 {
4152   switch (r_type)
4153     {
4154     case elfcpp::R_X86_64_NONE:
4155     case elfcpp::R_X86_64_GNU_VTINHERIT:
4156     case elfcpp::R_X86_64_GNU_VTENTRY:
4157     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
4158     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
4159     case elfcpp::R_X86_64_TLSDESC_CALL:
4160     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
4161     case elfcpp::R_X86_64_DTPOFF32:
4162     case elfcpp::R_X86_64_DTPOFF64:
4163     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
4164     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
4165       return 0;
4166
4167     case elfcpp::R_X86_64_64:
4168     case elfcpp::R_X86_64_PC64:
4169     case elfcpp::R_X86_64_GOTOFF64:
4170     case elfcpp::R_X86_64_GOTPC64:
4171     case elfcpp::R_X86_64_PLTOFF64:
4172     case elfcpp::R_X86_64_GOT64:
4173     case elfcpp::R_X86_64_GOTPCREL64:
4174     case elfcpp::R_X86_64_GOTPCREL:
4175     case elfcpp::R_X86_64_GOTPLT64:
4176       return 8;
4177
4178     case elfcpp::R_X86_64_32:
4179     case elfcpp::R_X86_64_32S:
4180     case elfcpp::R_X86_64_PC32:
4181     case elfcpp::R_X86_64_PC32_BND:
4182     case elfcpp::R_X86_64_PLT32:
4183     case elfcpp::R_X86_64_PLT32_BND:
4184     case elfcpp::R_X86_64_GOTPC32:
4185     case elfcpp::R_X86_64_GOT32:
4186       return 4;
4187
4188     case elfcpp::R_X86_64_16:
4189     case elfcpp::R_X86_64_PC16:
4190       return 2;
4191
4192     case elfcpp::R_X86_64_8:
4193     case elfcpp::R_X86_64_PC8:
4194       return 1;
4195
4196     case elfcpp::R_X86_64_COPY:
4197     case elfcpp::R_X86_64_GLOB_DAT:
4198     case elfcpp::R_X86_64_JUMP_SLOT:
4199     case elfcpp::R_X86_64_RELATIVE:
4200     case elfcpp::R_X86_64_IRELATIVE:
4201       // These are outstanding tls relocs, which are unexpected when linking
4202     case elfcpp::R_X86_64_TPOFF64:
4203     case elfcpp::R_X86_64_DTPMOD64:
4204     case elfcpp::R_X86_64_TLSDESC:
4205       object->error(_("unexpected reloc %u in object file"), r_type);
4206       return 0;
4207
4208     case elfcpp::R_X86_64_SIZE32:
4209     case elfcpp::R_X86_64_SIZE64:
4210     default:
4211       object->error(_("unsupported reloc %u against local symbol"), r_type);
4212       return 0;
4213     }
4214 }
4215
4216 // Scan the relocs during a relocatable link.
4217
4218 template<int size>
4219 void
4220 Target_x86_64<size>::scan_relocatable_relocs(
4221     Symbol_table* symtab,
4222     Layout* layout,
4223     Sized_relobj_file<size, false>* object,
4224     unsigned int data_shndx,
4225     unsigned int sh_type,
4226     const unsigned char* prelocs,
4227     size_t reloc_count,
4228     Output_section* output_section,
4229     bool needs_special_offset_handling,
4230     size_t local_symbol_count,
4231     const unsigned char* plocal_symbols,
4232     Relocatable_relocs* rr)
4233 {
4234   gold_assert(sh_type == elfcpp::SHT_RELA);
4235
4236   typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
4237     Relocatable_size_for_reloc> Scan_relocatable_relocs;
4238
4239   gold::scan_relocatable_relocs<size, false, elfcpp::SHT_RELA,
4240       Scan_relocatable_relocs>(
4241     symtab,
4242     layout,
4243     object,
4244     data_shndx,
4245     prelocs,
4246     reloc_count,
4247     output_section,
4248     needs_special_offset_handling,
4249     local_symbol_count,
4250     plocal_symbols,
4251     rr);
4252 }
4253
4254 // Relocate a section during a relocatable link.
4255
4256 template<int size>
4257 void
4258 Target_x86_64<size>::relocate_relocs(
4259     const Relocate_info<size, false>* relinfo,
4260     unsigned int sh_type,
4261     const unsigned char* prelocs,
4262     size_t reloc_count,
4263     Output_section* output_section,
4264     typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
4265     const Relocatable_relocs* rr,
4266     unsigned char* view,
4267     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
4268     section_size_type view_size,
4269     unsigned char* reloc_view,
4270     section_size_type reloc_view_size)
4271 {
4272   gold_assert(sh_type == elfcpp::SHT_RELA);
4273
4274   gold::relocate_relocs<size, false, elfcpp::SHT_RELA>(
4275     relinfo,
4276     prelocs,
4277     reloc_count,
4278     output_section,
4279     offset_in_output_section,
4280     rr,
4281     view,
4282     view_address,
4283     view_size,
4284     reloc_view,
4285     reloc_view_size);
4286 }
4287
4288 // Return the value to use for a dynamic which requires special
4289 // treatment.  This is how we support equality comparisons of function
4290 // pointers across shared library boundaries, as described in the
4291 // processor specific ABI supplement.
4292
4293 template<int size>
4294 uint64_t
4295 Target_x86_64<size>::do_dynsym_value(const Symbol* gsym) const
4296 {
4297   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
4298   return this->plt_address_for_global(gsym);
4299 }
4300
4301 // Return a string used to fill a code section with nops to take up
4302 // the specified length.
4303
4304 template<int size>
4305 std::string
4306 Target_x86_64<size>::do_code_fill(section_size_type length) const
4307 {
4308   if (length >= 16)
4309     {
4310       // Build a jmpq instruction to skip over the bytes.
4311       unsigned char jmp[5];
4312       jmp[0] = 0xe9;
4313       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
4314       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
4315               + std::string(length - 5, static_cast<char>(0x90)));
4316     }
4317
4318   // Nop sequences of various lengths.
4319   const char nop1[1] = { '\x90' };                 // nop
4320   const char nop2[2] = { '\x66', '\x90' };         // xchg %ax %ax
4321   const char nop3[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
4322   const char nop4[4] = { '\x0f', '\x1f', '\x40',   // nop 0(%rax)
4323                          '\x00'};
4324   const char nop5[5] = { '\x0f', '\x1f', '\x44',   // nop 0(%rax,%rax,1)
4325                          '\x00', '\x00' };
4326   const char nop6[6] = { '\x66', '\x0f', '\x1f',   // nopw 0(%rax,%rax,1)
4327                          '\x44', '\x00', '\x00' };
4328   const char nop7[7] = { '\x0f', '\x1f', '\x80',   // nopl 0L(%rax)
4329                          '\x00', '\x00', '\x00',
4330                          '\x00' };
4331   const char nop8[8] = { '\x0f', '\x1f', '\x84',   // nopl 0L(%rax,%rax,1)
4332                          '\x00', '\x00', '\x00',
4333                          '\x00', '\x00' };
4334   const char nop9[9] = { '\x66', '\x0f', '\x1f',   // nopw 0L(%rax,%rax,1)
4335                          '\x84', '\x00', '\x00',
4336                          '\x00', '\x00', '\x00' };
4337   const char nop10[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4338                            '\x1f', '\x84', '\x00',
4339                            '\x00', '\x00', '\x00',
4340                            '\x00' };
4341   const char nop11[11] = { '\x66', '\x66', '\x2e', // data16
4342                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4343                            '\x00', '\x00', '\x00',
4344                            '\x00', '\x00' };
4345   const char nop12[12] = { '\x66', '\x66', '\x66', // data16; data16
4346                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4347                            '\x84', '\x00', '\x00',
4348                            '\x00', '\x00', '\x00' };
4349   const char nop13[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4350                            '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4351                            '\x1f', '\x84', '\x00',
4352                            '\x00', '\x00', '\x00',
4353                            '\x00' };
4354   const char nop14[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4355                            '\x66', '\x66', '\x2e', // data16
4356                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4357                            '\x00', '\x00', '\x00',
4358                            '\x00', '\x00' };
4359   const char nop15[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4360                            '\x66', '\x66', '\x66', // data16; data16
4361                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4362                            '\x84', '\x00', '\x00',
4363                            '\x00', '\x00', '\x00' };
4364
4365   const char* nops[16] = {
4366     NULL,
4367     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
4368     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
4369   };
4370
4371   return std::string(nops[length], length);
4372 }
4373
4374 // Return the addend to use for a target specific relocation.  The
4375 // only target specific relocation is R_X86_64_TLSDESC for a local
4376 // symbol.  We want to set the addend is the offset of the local
4377 // symbol in the TLS segment.
4378
4379 template<int size>
4380 uint64_t
4381 Target_x86_64<size>::do_reloc_addend(void* arg, unsigned int r_type,
4382                                      uint64_t) const
4383 {
4384   gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
4385   uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
4386   gold_assert(intarg < this->tlsdesc_reloc_info_.size());
4387   const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
4388   const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
4389   gold_assert(psymval->is_tls_symbol());
4390   // The value of a TLS symbol is the offset in the TLS segment.
4391   return psymval->value(ti.object, 0);
4392 }
4393
4394 // Return the value to use for the base of a DW_EH_PE_datarel offset
4395 // in an FDE.  Solaris and SVR4 use DW_EH_PE_datarel because their
4396 // assembler can not write out the difference between two labels in
4397 // different sections, so instead of using a pc-relative value they
4398 // use an offset from the GOT.
4399
4400 template<int size>
4401 uint64_t
4402 Target_x86_64<size>::do_ehframe_datarel_base() const
4403 {
4404   gold_assert(this->global_offset_table_ != NULL);
4405   Symbol* sym = this->global_offset_table_;
4406   Sized_symbol<size>* ssym = static_cast<Sized_symbol<size>*>(sym);
4407   return ssym->value();
4408 }
4409
4410 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4411 // compiled with -fsplit-stack.  The function calls non-split-stack
4412 // code.  We have to change the function so that it always ensures
4413 // that it has enough stack space to run some random function.
4414
4415 template<int size>
4416 void
4417 Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx,
4418                                         section_offset_type fnoffset,
4419                                         section_size_type fnsize,
4420                                         unsigned char* view,
4421                                         section_size_type view_size,
4422                                         std::string* from,
4423                                         std::string* to) const
4424 {
4425   // The function starts with a comparison of the stack pointer and a
4426   // field in the TCB.  This is followed by a jump.
4427
4428   // cmp %fs:NN,%rsp
4429   if (this->match_view(view, view_size, fnoffset, "\x64\x48\x3b\x24\x25", 5)
4430       && fnsize > 9)
4431     {
4432       // We will call __morestack if the carry flag is set after this
4433       // comparison.  We turn the comparison into an stc instruction
4434       // and some nops.
4435       view[fnoffset] = '\xf9';
4436       this->set_view_to_nop(view, view_size, fnoffset + 1, 8);
4437     }
4438   // lea NN(%rsp),%r10
4439   // lea NN(%rsp),%r11
4440   else if ((this->match_view(view, view_size, fnoffset,
4441                              "\x4c\x8d\x94\x24", 4)
4442             || this->match_view(view, view_size, fnoffset,
4443                                 "\x4c\x8d\x9c\x24", 4))
4444            && fnsize > 8)
4445     {
4446       // This is loading an offset from the stack pointer for a
4447       // comparison.  The offset is negative, so we decrease the
4448       // offset by the amount of space we need for the stack.  This
4449       // means we will avoid calling __morestack if there happens to
4450       // be plenty of space on the stack already.
4451       unsigned char* pval = view + fnoffset + 4;
4452       uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
4453       val -= parameters->options().split_stack_adjust_size();
4454       elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
4455     }
4456   else
4457     {
4458       if (!object->has_no_split_stack())
4459         object->error(_("failed to match split-stack sequence at "
4460                         "section %u offset %0zx"),
4461                       shndx, static_cast<size_t>(fnoffset));
4462       return;
4463     }
4464
4465   // We have to change the function so that it calls
4466   // __morestack_non_split instead of __morestack.  The former will
4467   // allocate additional stack space.
4468   *from = "__morestack";
4469   *to = "__morestack_non_split";
4470 }
4471
4472 // The selector for x86_64 object files.  Note this is never instantiated
4473 // directly.  It's only used in Target_selector_x86_64_nacl, below.
4474
4475 template<int size>
4476 class Target_selector_x86_64 : public Target_selector_freebsd
4477 {
4478 public:
4479   Target_selector_x86_64()
4480     : Target_selector_freebsd(elfcpp::EM_X86_64, size, false,
4481                               (size == 64
4482                                ? "elf64-x86-64" : "elf32-x86-64"),
4483                               (size == 64
4484                                ? "elf64-x86-64-freebsd"
4485                                : "elf32-x86-64-freebsd"),
4486                               (size == 64 ? "elf_x86_64" : "elf32_x86_64"))
4487   { }
4488
4489   Target*
4490   do_instantiate_target()
4491   { return new Target_x86_64<size>(); }
4492
4493 };
4494
4495 // NaCl variant.  It uses different PLT contents.
4496
4497 template<int size>
4498 class Output_data_plt_x86_64_nacl : public Output_data_plt_x86_64<size>
4499 {
4500  public:
4501   Output_data_plt_x86_64_nacl(Layout* layout,
4502                               Output_data_got<64, false>* got,
4503                               Output_data_space* got_plt,
4504                               Output_data_space* got_irelative)
4505     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4506                                    got, got_plt, got_irelative)
4507   { }
4508
4509   Output_data_plt_x86_64_nacl(Layout* layout,
4510                               Output_data_got<64, false>* got,
4511                               Output_data_space* got_plt,
4512                               Output_data_space* got_irelative,
4513                               unsigned int plt_count)
4514     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4515                                    got, got_plt, got_irelative,
4516                                    plt_count)
4517   { }
4518
4519  protected:
4520   virtual unsigned int
4521   do_get_plt_entry_size() const
4522   { return plt_entry_size; }
4523
4524   virtual void
4525   do_add_eh_frame(Layout* layout)
4526   {
4527     layout->add_eh_frame_for_plt(this,
4528                                  this->plt_eh_frame_cie,
4529                                  this->plt_eh_frame_cie_size,
4530                                  plt_eh_frame_fde,
4531                                  plt_eh_frame_fde_size);
4532   }
4533
4534   virtual void
4535   do_fill_first_plt_entry(unsigned char* pov,
4536                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
4537                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
4538
4539   virtual unsigned int
4540   do_fill_plt_entry(unsigned char* pov,
4541                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4542                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4543                     unsigned int got_offset,
4544                     unsigned int plt_offset,
4545                     unsigned int plt_index);
4546
4547   virtual void
4548   do_fill_tlsdesc_entry(unsigned char* pov,
4549                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4550                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4551                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4552                         unsigned int tlsdesc_got_offset,
4553                         unsigned int plt_offset);
4554
4555  private:
4556   // The size of an entry in the PLT.
4557   static const int plt_entry_size = 64;
4558
4559   // The first entry in the PLT.
4560   static const unsigned char first_plt_entry[plt_entry_size];
4561
4562   // Other entries in the PLT for an executable.
4563   static const unsigned char plt_entry[plt_entry_size];
4564
4565   // The reserved TLSDESC entry in the PLT for an executable.
4566   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
4567
4568   // The .eh_frame unwind information for the PLT.
4569   static const int plt_eh_frame_fde_size = 32;
4570   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4571 };
4572
4573 template<int size>
4574 class Target_x86_64_nacl : public Target_x86_64<size>
4575 {
4576  public:
4577   Target_x86_64_nacl()
4578     : Target_x86_64<size>(&x86_64_nacl_info)
4579   { }
4580
4581   virtual Output_data_plt_x86_64<size>*
4582   do_make_data_plt(Layout* layout,
4583                    Output_data_got<64, false>* got,
4584                    Output_data_space* got_plt,
4585                    Output_data_space* got_irelative)
4586   {
4587     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4588                                                  got_irelative);
4589   }
4590
4591   virtual Output_data_plt_x86_64<size>*
4592   do_make_data_plt(Layout* layout,
4593                    Output_data_got<64, false>* got,
4594                    Output_data_space* got_plt,
4595                    Output_data_space* got_irelative,
4596                    unsigned int plt_count)
4597   {
4598     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4599                                                  got_irelative,
4600                                                  plt_count);
4601   }
4602
4603   virtual std::string
4604   do_code_fill(section_size_type length) const;
4605
4606  private:
4607   static const Target::Target_info x86_64_nacl_info;
4608 };
4609
4610 template<>
4611 const Target::Target_info Target_x86_64_nacl<64>::x86_64_nacl_info =
4612 {
4613   64,                   // size
4614   false,                // is_big_endian
4615   elfcpp::EM_X86_64,    // machine_code
4616   false,                // has_make_symbol
4617   false,                // has_resolve
4618   true,                 // has_code_fill
4619   true,                 // is_default_stack_executable
4620   true,                 // can_icf_inline_merge_sections
4621   '\0',                 // wrap_char
4622   "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
4623   0x20000,              // default_text_segment_address
4624   0x10000,              // abi_pagesize (overridable by -z max-page-size)
4625   0x10000,              // common_pagesize (overridable by -z common-page-size)
4626   true,                 // isolate_execinstr
4627   0x10000000,           // rosegment_gap
4628   elfcpp::SHN_UNDEF,    // small_common_shndx
4629   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
4630   0,                    // small_common_section_flags
4631   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
4632   NULL,                 // attributes_section
4633   NULL,                 // attributes_vendor
4634   "_start"              // entry_symbol_name
4635 };
4636
4637 template<>
4638 const Target::Target_info Target_x86_64_nacl<32>::x86_64_nacl_info =
4639 {
4640   32,                   // size
4641   false,                // is_big_endian
4642   elfcpp::EM_X86_64,    // machine_code
4643   false,                // has_make_symbol
4644   false,                // has_resolve
4645   true,                 // has_code_fill
4646   true,                 // is_default_stack_executable
4647   true,                 // can_icf_inline_merge_sections
4648   '\0',                 // wrap_char
4649   "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
4650   0x20000,              // default_text_segment_address
4651   0x10000,              // abi_pagesize (overridable by -z max-page-size)
4652   0x10000,              // common_pagesize (overridable by -z common-page-size)
4653   true,                 // isolate_execinstr
4654   0x10000000,           // rosegment_gap
4655   elfcpp::SHN_UNDEF,    // small_common_shndx
4656   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
4657   0,                    // small_common_section_flags
4658   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
4659   NULL,                 // attributes_section
4660   NULL,                 // attributes_vendor
4661   "_start"              // entry_symbol_name
4662 };
4663
4664 #define NACLMASK        0xe0            // 32-byte alignment mask.
4665
4666 // The first entry in the PLT.
4667
4668 template<int size>
4669 const unsigned char
4670 Output_data_plt_x86_64_nacl<size>::first_plt_entry[plt_entry_size] =
4671 {
4672   0xff, 0x35,                         // pushq contents of memory address
4673   0, 0, 0, 0,                         // replaced with address of .got + 8
4674   0x4c, 0x8b, 0x1d,                   // mov GOT+16(%rip), %r11
4675   0, 0, 0, 0,                         // replaced with address of .got + 16
4676   0x41, 0x83, 0xe3, NACLMASK,         // and $-32, %r11d
4677   0x4d, 0x01, 0xfb,                   // add %r15, %r11
4678   0x41, 0xff, 0xe3,                   // jmpq *%r11
4679
4680   // 9-byte nop sequence to pad out to the next 32-byte boundary.
4681   0x66, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw 0x0(%rax,%rax,1)
4682
4683   // 32 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   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4687   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4688   0x66,                                  // excess data32 prefix
4689   0x90                                   // nop
4690 };
4691
4692 template<int size>
4693 void
4694 Output_data_plt_x86_64_nacl<size>::do_fill_first_plt_entry(
4695     unsigned char* pov,
4696     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4697     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
4698 {
4699   memcpy(pov, first_plt_entry, plt_entry_size);
4700   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4701                                               (got_address + 8
4702                                                - (plt_address + 2 + 4)));
4703   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4704                                               (got_address + 16
4705                                                - (plt_address + 9 + 4)));
4706 }
4707
4708 // Subsequent entries in the PLT.
4709
4710 template<int size>
4711 const unsigned char
4712 Output_data_plt_x86_64_nacl<size>::plt_entry[plt_entry_size] =
4713 {
4714   0x4c, 0x8b, 0x1d,              // mov name@GOTPCREL(%rip),%r11
4715   0, 0, 0, 0,                    // replaced with address of symbol in .got
4716   0x41, 0x83, 0xe3, NACLMASK,    // and $-32, %r11d
4717   0x4d, 0x01, 0xfb,              // add %r15, %r11
4718   0x41, 0xff, 0xe3,              // jmpq *%r11
4719
4720   // 15-byte nop sequence to pad out to the next 32-byte boundary.
4721   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4722   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4723
4724   // Lazy GOT entries point here (32-byte aligned).
4725   0x68,                       // pushq immediate
4726   0, 0, 0, 0,                 // replaced with index into relocation table
4727   0xe9,                       // jmp relative
4728   0, 0, 0, 0,                 // replaced with offset to start of .plt0
4729
4730   // 22 bytes of nop to pad out to the standard size.
4731   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4732   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4733   0x0f, 0x1f, 0x80, 0, 0, 0, 0,          // nopl 0x0(%rax)
4734 };
4735
4736 template<int size>
4737 unsigned int
4738 Output_data_plt_x86_64_nacl<size>::do_fill_plt_entry(
4739     unsigned char* pov,
4740     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4741     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4742     unsigned int got_offset,
4743     unsigned int plt_offset,
4744     unsigned int plt_index)
4745 {
4746   memcpy(pov, plt_entry, plt_entry_size);
4747   elfcpp::Swap_unaligned<32, false>::writeval(pov + 3,
4748                                               (got_address + got_offset
4749                                                - (plt_address + plt_offset
4750                                                   + 3 + 4)));
4751
4752   elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_index);
4753   elfcpp::Swap_unaligned<32, false>::writeval(pov + 38,
4754                                               - (plt_offset + 38 + 4));
4755
4756   return 32;
4757 }
4758
4759 // The reserved TLSDESC entry in the PLT.
4760
4761 template<int size>
4762 const unsigned char
4763 Output_data_plt_x86_64_nacl<size>::tlsdesc_plt_entry[plt_entry_size] =
4764 {
4765   0xff, 0x35,                   // pushq x(%rip)
4766   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
4767   0x4c, 0x8b, 0x1d,             // mov y(%rip),%r11
4768   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
4769   0x41, 0x83, 0xe3, NACLMASK,   // and $-32, %r11d
4770   0x4d, 0x01, 0xfb,             // add %r15, %r11
4771   0x41, 0xff, 0xe3,             // jmpq *%r11
4772
4773   // 41 bytes of nop to pad out to the standard size.
4774   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4775   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4776   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4777   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4778   0x66, 0x66,                            // excess data32 prefixes
4779   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4780 };
4781
4782 template<int size>
4783 void
4784 Output_data_plt_x86_64_nacl<size>::do_fill_tlsdesc_entry(
4785     unsigned char* pov,
4786     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4787     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4788     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4789     unsigned int tlsdesc_got_offset,
4790     unsigned int plt_offset)
4791 {
4792   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
4793   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4794                                               (got_address + 8
4795                                                - (plt_address + plt_offset
4796                                                   + 2 + 4)));
4797   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4798                                               (got_base
4799                                                + tlsdesc_got_offset
4800                                                - (plt_address + plt_offset
4801                                                   + 9 + 4)));
4802 }
4803
4804 // The .eh_frame unwind information for the PLT.
4805
4806 template<int size>
4807 const unsigned char
4808 Output_data_plt_x86_64_nacl<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4809 {
4810   0, 0, 0, 0,                           // Replaced with offset to .plt.
4811   0, 0, 0, 0,                           // Replaced with size of .plt.
4812   0,                                    // Augmentation size.
4813   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
4814   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
4815   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
4816   elfcpp::DW_CFA_advance_loc + 58,      // Advance 58 to __PLT__ + 64.
4817   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
4818   13,                                   // Block length.
4819   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
4820   elfcpp::DW_OP_breg16, 0,              // Push %rip.
4821   elfcpp::DW_OP_const1u, 63,            // Push 0x3f.
4822   elfcpp::DW_OP_and,                    // & (%rip & 0x3f).
4823   elfcpp::DW_OP_const1u, 37,            // Push 0x25.
4824   elfcpp::DW_OP_ge,                     // >= ((%rip & 0x3f) >= 0x25)
4825   elfcpp::DW_OP_lit3,                   // Push 3.
4826   elfcpp::DW_OP_shl,                    // << (((%rip & 0x3f) >= 0x25) << 3)
4827   elfcpp::DW_OP_plus,                   // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
4828   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
4829   elfcpp::DW_CFA_nop
4830 };
4831
4832 // Return a string used to fill a code section with nops.
4833 // For NaCl, long NOPs are only valid if they do not cross
4834 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4835 template<int size>
4836 std::string
4837 Target_x86_64_nacl<size>::do_code_fill(section_size_type length) const
4838 {
4839   return std::string(length, static_cast<char>(0x90));
4840 }
4841
4842 // The selector for x86_64-nacl object files.
4843
4844 template<int size>
4845 class Target_selector_x86_64_nacl
4846   : public Target_selector_nacl<Target_selector_x86_64<size>,
4847                                 Target_x86_64_nacl<size> >
4848 {
4849  public:
4850   Target_selector_x86_64_nacl()
4851     : Target_selector_nacl<Target_selector_x86_64<size>,
4852                            Target_x86_64_nacl<size> >("x86-64",
4853                                                       size == 64
4854                                                       ? "elf64-x86-64-nacl"
4855                                                       : "elf32-x86-64-nacl",
4856                                                       size == 64
4857                                                       ? "elf_x86_64_nacl"
4858                                                       : "elf32_x86_64_nacl")
4859   { }
4860 };
4861
4862 Target_selector_x86_64_nacl<64> target_selector_x86_64;
4863 Target_selector_x86_64_nacl<32> target_selector_x32;
4864
4865 } // End anonymous namespace.